182 results on '"Michele Parker"'
Search Results
2. Assessment of Papillary Muscle Infarction with Dark-Blood Delayed Enhancement Cardiac MRI in Canines and Humans
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David Wendell, Elizabeth Jenista, Han W. Kim, Enn-Ling Chen, Clerio F. Azevedo, Yodying Kaolawanich, Fawaz Alenezi, Wolfgang Rehwald, Stephen Darty, Michele Parker, and Raymond J. Kim
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Male ,Dogs ,Infarction ,Myocardial Infarction ,Humans ,Animals ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Middle Aged ,Papillary Muscles ,Coronary Angiography ,Coronary Vessels ,Magnetic Resonance Imaging - Abstract
Background The relationship between papillary muscle infarction (papMI) and the culprit coronary lesion has not been fully investigated. Delayed enhancement cardiac MRI may detect papMI, yet its accuracy is unknown. Flow-independent dark-blood delayed enhancement (FIDDLE) cardiac MRI has been shown to improve the detection of myocardial infarction adjacent to blood pool. Purpose To assess the diagnostic performance of delayed enhancement and FIDDLE cardiac MRI for the detection of papMI, and to investigate the prevalence of papMI and its relationship to the location of the culprit coronary lesion. Materials and Methods A prospective canine study was used to determine the accuracy of conventional delayed enhancement imaging and FIDDLE imaging for detection of papMI, with pathology-based findings as the reference standard. Participants with first-time myocardial infarction with a clear culprit lesion at coronary angiography were prospectively enrolled at a single hospital from 2015 to 2018 and compared against control participants with low Framingham risk scores. In canines, diagnostic accuracy was calculated for delayed enhancement and FIDDLE imaging. Results In canines (
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- 2022
3. Catfish: Exploring the Individual Predictors and Interpersonal Characteristics of Deceptive Online Romantic Relationships
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Michele Parker and Kelly Campbell
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Cultural Studies ,Clinical Psychology ,Social Psychology ,Social Sciences (miscellaneous) - Published
- 2022
4. The Sonnet-Ballad
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LANTZ, NICK, primary, MAY, JAMAAL, additional, RANDALL, MICHELE PARKER, additional, WOLFF, VIRGINIA EUWER, additional, and YU, TIMOTHY, additional
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- 2019
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5. Myocardial Contractile Mechanics in Ischemic Mitral Regurgitation
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Jonathan D. Kochav, Jiwon Kim, Robert Judd, Katherine A. Tak, Emmad Janjua, Abigail J. Maciejewski, Han W. Kim, Igor Klem, John Heitner, Dipan Shah, William A. Zoghbi, Chetan Shenoy, Afshin Farzaneh-Far, Venkateshwar Polsani, Pablo Villar-Calle, Michele Parker, Kevin M. Judd, Omar K. Khalique, Martin B. Leon, Richard B. Devereux, Robert A. Levine, Raymond J. Kim, and Jonathan W. Weinsaft
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Radiology, Nuclear Medicine and imaging ,Cardiology and Cardiovascular Medicine - Published
- 2022
6. Overcoming barriers to collaborative health care: A phenomenological study of medical providers
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Michele Parker and Rachel Diamond
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- 2022
7. Military Experience and School Leadership Development in North Carolina
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Robert Guzman, Michele Parker, Brian Gano, Margaret Mishra, and Tammy Ferguson Shaw
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- 2022
8. Attached to Technology: Exploring Young Adults’ Attachments to Parents, Partners, and Phones
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Michele Parker, YiLe Su, and Marissa A. Mosley
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Social Psychology ,Social Sciences (miscellaneous) - Abstract
Cell phone use has become a mainstay in the lives of young adults, with 93% of Millennials owning a smartphone. With the increased accessibility of technology, individuals’ cell phone use may lead to personal distress in various facets of life. Specifically, problematic cell phone use may be the result of attempts to fulfill emotional needs or avoid connection with others. The present study used a systemic, attachment-based lens to investigate the roles of parental and romantic attachment in problematic cell phone use. A sample of 479 young adults (ages 18–26) completed an online survey gauging their cell phone use and attachment styles. Mediation analyzes were run to determine if adult attachment mediates the relationship from parental attachment to problematic cell phone use. The results found that attachment anxiety mediates the relationship between communication and alienation subscales for mother and alienation only for father to problematic cell phone use. Clinical implications are discussed with results informing assessment, prevention, and intervention efforts for individuals, families, and couples.
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- 2021
9. Santé le Match: A mobile health game application to educate the youth of Senegal
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Shelby Tadaki, Reha Shah, Michele Parker, Krizia Araracap, Evan Chou, Matthew Tolosa, Silvia Figueira, Carly Kellner, and Kristina Yin
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- 2022
10. Ischemia-Mediated Dysfunction in Subpapillary Myocardium as a Marker of Functional Mitral Regurgitation
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Chaya S. Moskowitz, Han W. Kim, Afshin Farzaneh-Far, Dipan J. Shah, Preston Cargile, Mark B. Ratcliffe, William A. Zoghbi, Robert A. Levine, Martin B. Leon, Raymond J. Kim, Razia Sultana, Venkateshwar Polsani, Chetan Shenoy, Ramsey Kalil, Michele Parker, Jiwon Kim, John F. Heitner, Dimitrios Karmpaliotis, Omar K. Khalique, Richard B. Devereux, Igor Klem, Robert M. Judd, Jonathan D. Kochav, Lakshmi Nambiar, Pablo Villar-Calle, and Jonathan W. Weinsaft
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Male ,medicine.medical_specialty ,Ischemia ,Infarction ,030204 cardiovascular system & hematology ,Ventricular Function, Left ,030218 nuclear medicine & medical imaging ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Internal medicine ,Mitral valve ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Aged ,Mitral regurgitation ,business.industry ,Mitral Valve Insufficiency ,Stroke Volume ,Stroke volume ,Odds ratio ,Middle Aged ,Papillary Muscles ,medicine.disease ,medicine.anatomical_structure ,Ventricle ,cardiovascular system ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business - Abstract
The goal of this study was to test whether ischemia-mediated contractile dysfunction underlying the mitral valve affects functional mitral regurgitation (FMR) and the prognostic impact of FMR.FMR results from left ventricular (LV) remodeling, which can stem from myocardial tissue alterations. Stress cardiac magnetic resonance can assess ischemia and infarction in the left ventricle and papillary muscles; relative impact on FMR is uncertain.Vasodilator stress cardiac magnetic resonance was performed in patients with known or suspected coronary artery disease at 7 sites. Images were centrally analyzed for MR etiology/severity, mitral apparatus remodeling, and papillary ischemia.A total of 8,631 patients (mean age 60.0 ± 14.1 years; 55% male) were studied. FMR was present in 27%, among whom 16% (n = 372) had advanced (moderate or severe) FMR. Patients with ischemia localized to subpapillary regions were more likely to have advanced FMR (p = 0.003); those with ischemia localized to other areas were not (p = 0.17). Ischemic/dysfunctional subpapillary myocardium (odds ratio: 1.24/10% subpapillary myocardium; confidence interval: 1.17 to 1.31; p 0.001) was associated with advanced FMR controlling for infarction. Among a subgroup with (n = 372) and without (n = 744) advanced FMR matched (1:2) on infarct size/distribution, patients with advanced FMR had increased adverse mitral apparatus remodeling, paralleled by greater ischemic/dysfunctional subpapillary myocardium (p 0.001). Although posteromedial papillary ischemia was more common with advanced FMR (p = 0.006), subpapillary ischemia with dysfunction remained associated (p 0.001), adjusting for posteromedial papillary ischemia (p = 0.074). During follow-up (median 5.1 years), 1,473 deaths occurred in the overall cohort; advanced FMR conferred increased mortality risk (hazard ratio: 1.52; 95% confidence interval: 1.25 to 1.86; p 0.001) controlling for left ventricular ejection fraction, infarction, and ischemia.Ischemic and dysfunctional subpapillary myocardium provides a substrate for FMR, which predicts mortality independent of key mechanistic substrates.
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- 2021
11. ECG-gated MR angiography provides better reproducibility for standard aortic measurements
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Clerio F. Azevedo, Han W. Kim, Stephen Darty, Michele Parker, Elizabeth R. Jenista, Logan R Smith, Raymond J. Kim, George L Gamoneda, and David C. Wendell
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Aortic arch ,Aorta ,medicine.medical_specialty ,Reproducibility ,medicine.diagnostic_test ,business.industry ,General Medicine ,Magnetic resonance angiography ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,medicine.artery ,Descending aorta ,Angiography ,Ascending aorta ,cardiovascular system ,medicine ,Thoracic aorta ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Radiology ,business ,Nuclear medicine - Abstract
Cardiac motion and aortic pulsatility can affect the image quality of 3D contrast-enhanced MR angiography (CE-MRA). The addition of ECG gating improves image quality; however, no studies have directly linked image quality improvements to clinically used measures. In this study, we directly compared diameter measurements in the same patient from ECG-gated to non-gated CE-MRA to evaluate the impact of ECG gating upon measurement reproducibility. Fifty-three patients, referred for thoracic aortic angiography, were enrolled and underwent both non-gated and ECG-gated CE-MRA. Two readers independently measured vessel diameter, image quality, and vessel sharpness at the sinus of Valsalva (SOV), sinotubular junction (STJX), ascending aorta (AAO), distal aortic arch (DLSA), and descending aorta (DAO). Measurement reliability and reproducibility were compared between methods. Image quality with ECG gating was rated significantly higher at the SOV (3.2 ± 0.9 vs 1.2 ± 1.0, p < 0.0001), STJX (3.4 ± 0.7 vs 1.8 ± 1.0, p < 0.0001), AAO (3.5 ± 0.6 vs 1.7 ± 1.1 p < 0.0001), DLSA (4.0 ± 0.1 vs 3.6 ± 0.7, p = 0.006), and DAO (4.0 ± 0.1 vs 3.4 ± 0.9 p < 0.0001) than for non-gated studies. Bland-Altman analyses demonstrated that inter- and intra-observer variability was significantly smaller for ECG-gated MRA at the SOV and AAO. For the non-gated images at the SOV, the 95% limits of agreement for both inter- and intra-observer variability exceeded the growth-rate cutoff for surgical repair (0.5 cm). At the DAO, variability was similar between the two techniques. ECG-gated CE-MRA resulted in improved reproducibility in aortic root and ascending aortic measurements. These data suggest that ECG-gated CE-MRA should be used for the serial assessment of the ascending thoracic aorta. • ECG-gated CE-MRA improves the reproducibility and repeatability of measurements of the ascending aorta. • With non-gated CE-MRA, pulsatile motion in the proximal aorta results in significant variability in measurement reproducibility.
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- 2021
12. Abstract 11227: Ischemia Mediated Contractile Dysfunction Modulates Functional Mitral Regurgitation - Multiparametric Strain and Tissue Characterization Data from the Society of Cardiovascular Magnetic Resonance (scmr) Registry
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Abigail Maciejewski, Jonathan Kochav, Jiwon Kim, Katherine Tak, Robert M Judd, Han Kim, John F Heitner, Dipan J Shah, Chetan Shenoy, Afshin FARZANEH-FAR, Venkateshwar R Polsani, Michele Parker, Omar Khalique, Martin B Leon, Mark B Ratcliffe, Robert Levine, William A Zoghbi, Richard B Devereux, Raymond J Kim, and Jonathan W Weinsaft
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Physiology (medical) ,cardiovascular diseases ,Cardiology and Cardiovascular Medicine - Abstract
Introduction: LV ischemia has been linked to functional mitral regurgitation (FMR) but ischemia is present many pts without FMR. CMR concomitantly assesses MR, ischemia and LV function but has not been used to test factors modifying impact of ischemia on FMR. Methods: Vasodilator stress CMR was performed in CAD pts in a multicenter registry, in whom advanced (≥moderate) FMR was confirmed by core lab. LV ischemia was categorized by subpapillary involvement (subtending mitral apparatus). To test mechanism by which ischemia impacts FMR, LV strain was measured in pts with ischemia and Results: 2639 pts were studied; 7% had advanced FMR. While FMR pts had more ischemia in subpapillary (21.8 ± 28.3 vs 13.4 ± 21.9%) and nonpapillary (19.2 ± 25.5 vs 13.0 ± 22.2%) regions (pFigure ). Adverse mitral remodeling associated with impaired strain; mitral tenting area (OR -0.01 per % [-0.02, -0.004] p Conclusions: Ischemia mediated LV dysfunction on multiparametric CMR modulates likelihood of FMR and adverse prognosis.
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- 2021
13. Cardiovascular magnetic resonance imaging in suspected cardiac tumour: a multicentre outcomes study
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Marianna Zagurovskaya, Raymond J. Kim, Michele Parker, Dipan J. Shah, Michael J. Reardon, Han W. Kim, Chetan Shenoy, John D. Grizzard, and Mahwash Kassi
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medicine.medical_specialty ,Magnetic Resonance Spectroscopy ,Magnetic Resonance Imaging, Cine ,Malignancy ,Risk Assessment ,Ventricular Function, Left ,Coronary artery disease ,Heart Neoplasms ,Predictive Value of Tests ,Clinical Research ,medicine ,Clinical endpoint ,Humans ,cardiovascular diseases ,Thrombus ,Medical diagnosis ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Hazard ratio ,Magnetic resonance imaging ,Stroke Volume ,medicine.disease ,Prognosis ,Magnetic Resonance Imaging ,cardiovascular system ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Abstract
Aims Cardiovascular magnetic resonance (CMR) imaging is a key diagnostic tool for the evaluation of patients with suspected cardiac tumours. Patient management is guided by the CMR diagnosis, including no further testing if a mass is excluded or if only a pseudomass is found. However, there are no outcomes studies validating this approach. Methods and results In this multicentre study of patients undergoing clinical CMR for suspected cardiac tumour, CMR diagnoses were assigned as no mass, pseudomass, thrombus, benign tumour, or malignant tumour. A final diagnosis was determined after follow-up using all available data. The primary endpoint was all-cause mortality. Among 903 patients, the CMR diagnosis was no mass in 25%, pseudomass in 16%, thrombus in 16%, benign tumour in 17%, and malignant tumour in 23%. Over a median of 4.9 years, 376 patients died. Compared with the final diagnosis, the CMR diagnosis was accurate in 98.4% of patients. Patients with CMR diagnoses of pseudomass and benign tumour had similar mortality to those with no mass, whereas those with malignant tumour [hazard ratio (HR) 3.31 (2.40–4.57)] and thrombus [HR 1.46 (1.00–2.11)] had greater mortality. The CMR diagnosis provided incremental prognostic value over clinical factors including left ventricular ejection fraction, coronary artery disease, and history of extracardiac malignancy (P Conclusion In patients with suspected cardiac tumour, CMR has high diagnostic accuracy. Patients with CMR diagnoses of no mass, pseudomass, and benign tumour have similar long-term mortality. The CMR diagnosis is a powerful independent predictor of mortality incremental to clinical risk factors.
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- 2021
14. Myocardial Contractile Mechanics in Ischemic Mitral Regurgitation: Multicenter Data Using Stress Perfusion Cardiovascular Magnetic Resonance
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Jonathan D, Kochav, Jiwon, Kim, Robert, Judd, Katherine A, Tak, Emmad, Janjua, Abigail J, Maciejewski, Han W, Kim, Igor, Klem, John, Heitner, Dipan, Shah, William A, Zoghbi, Chetan, Shenoy, Afshin, Farzaneh-Far, Venkateshwar, Polsani, Pablo, Villar-Calle, Michele, Parker, Kevin M, Judd, Omar K, Khalique, Martin B, Leon, Richard B, Devereux, Robert A, Levine, Raymond J, Kim, and Jonathan W, Weinsaft
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Perfusion ,Magnetic Resonance Spectroscopy ,Infarction ,Ischemia ,Predictive Value of Tests ,Myocardium ,Humans ,Mitral Valve Insufficiency - Abstract
Left ventricular (LV) ischemia has been variably associated with functional mitral regurgitation (FMR). Determinants of FMR in patients with ischemia are poorly understood.This study sought to test whether contractile mechanics in ischemic myocardium underlying the mitral valve have an impact on likelihood of FMR.Vasodilator stress perfusion cardiac magnetic resonance was performed in patients with coronary artery disease (CAD) at multiple centers. FMR severity was confirmed quantitatively via core lab analysis. To test relationship of contractile mechanics with ischemic FMR, regional wall motion and strain were assessed in patients with inducible ischemia and minimal (≤5% LV myocardium, nontransmural) infarction.A total of 2,647 patients with CAD were studied; 34% had FMR (7% moderate or greater). FMR severity increased with presence (P 0.001) and extent (P = 0.01) of subpapillary ischemia: patients with moderate or greater FMR had more subpapillary ischemia (odds ratio [OR]: 1.13 per 10% LV; 95% CI: 1.05-1.21; P = 0.001) independent of ischemia in remote regions (P = NS); moderate or greater FMR prevalence increased stepwise with extent of ischemia and infarction in subpapillary myocardium (P 0.001); stronger associations between FMR and infarction paralleled greater wall motion scores in infarct-affected territories. Among patients with inducible ischemia and minimal infarction (n = 532), wall motion and radial strain analysis showed impaired subpapillary contractile mechanics to associate with moderate or greater FMR (P 0.05) independent of remote regions (P = NS). Conversely, subpapillary ischemia without contractile dysfunction did not augment FMR likelihood. Mitral and interpapillary dimensions increased with subpapillary radial strain impairment; each remodeling parameter associated with impaired subpapillary strain (P 0.05) independent of remote strain (P = NS). Subpapillary radial strain (OR: 1.13 per 5% [95% CI: 1.02-1.25]; P = 0.02) and mitral tenting area (OR: 1.05 per 10 mmAmong patients with CAD and ischemia, FMR severity and adverse mitral apparatus remodeling increase in proportion to contractile dysfunction underlying the mitral valve.
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- 2021
15. Patients With Acute Myocarditis Following mRNA COVID-19 Vaccination
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Han W. Kim, Michael J Campbell, Stephen Darty, Michele Parker, David C. Wendell, Elizabeth R. Jenista, Clerio F. Azevedo, and Raymond J. Kim
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Adult ,Male ,Chest Pain ,medicine.medical_specialty ,Myocarditis ,COVID-19 Vaccines ,Gadolinium ,030204 cardiovascular system & hematology ,Chest pain ,03 medical and health sciences ,0302 clinical medicine ,Cardiac magnetic resonance imaging ,Internal medicine ,Outcome Assessment, Health Care ,medicine ,Humans ,Prospective Studies ,Registries ,030212 general & internal medicine ,RNA, Messenger ,Smallpox vaccine ,BNT162 Vaccine ,Aged ,Vaccines ,medicine.diagnostic_test ,business.industry ,SARS-CoV-2 ,Brief Report ,Vaccination ,COVID-19 ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,Hospitalization ,Cardiac Imaging Techniques ,Telephone interview ,Acute Disease ,Biomarker (medicine) ,Female ,Immunization ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,2019-nCoV Vaccine mRNA-1273 - Abstract
Importance Vaccine-associated myocarditis is an unusual entity that has been described for the smallpox vaccine, but only anecdotal case reports have been described for other vaccines. Whether COVID-19 vaccination may be linked to the occurrence of myocarditis is unknown. Objective To describe a group of 7 patients with acute myocarditis over 3 months, 4 of whom had recent messenger RNA (mRNA) COVID-19 vaccination. Design, Setting, and Participants All patients referred for cardiovascular magnetic resonance imaging at Duke University Medical Center were asked to participate in a prospective outcomes registry. Two searches of the registry database were performed: first, to identify patients with acute myocarditis for the 3-month period between February 1 and April 30 for 2017 through 2021, and second, to identify all patients with possible vaccine-associated myocarditis for the past 20 years. Once patients with possible vaccine-associated myocarditis were identified, data available in the registry were supplemented by additional data collection from the electronic health record and a telephone interview. Exposures mRNA COVID-19 vaccine. Main Outcomes and Measures Occurrence of acute myocarditis by cardiovascular magnetic resonance imaging. Results In the 3-month period between February 1 and April 30, 2021, 7 patients with acute myocarditis were identified, of which 4 occurred within 5 days of COVID-19 vaccination. Three were younger male individuals (age, 23-36 years) and 1 was a 70-year-old female individual. All 4 had received the second dose of an mRNA vaccine (2 received mRNA-1273 [Moderna], and 2 received BNT162b2 [Pfizer]). All presented with severe chest pain, had biomarker evidence of myocardial injury, and were hospitalized. Coincident testing for COVID-19 and respiratory viruses provided no alternative explanation. Cardiac magnetic resonance imaging findings were typical for myocarditis, including regional dysfunction, late gadolinium enhancement, and elevated native T1 and T2. Conclusions and Relevance In this study, magnetic resonance imaging findings were found to be consistent with acute myocarditis in 7 patients; 4 of whom had preceding COVID-19 vaccination. Further investigation is needed to determine associations of COVID-19 vaccination and myocarditis.
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- 2021
16. Prevalence and Prognosis of Unrecognized Myocardial Infarction in Asymptomatic Patients With Diabetes: A Two-Center Study With Up to 5 Years of Follow-up
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John F. Heitner, Han W. Kim, Daniel C. Lee, Michael D. Elliott, Robert O. Bonow, Dixon B. Kaufman, Edwin Wu, Michele Parker, Robert M. Judd, and Raymond J. Kim
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Advanced and Specialized Nursing ,Cardiovascular and Metabolic Risk ,medicine.medical_specialty ,Type 1 diabetes ,business.industry ,Endocrinology, Diabetes and Metabolism ,030209 endocrinology & metabolism ,Type 2 diabetes ,medicine.disease ,Asymptomatic ,03 medical and health sciences ,0302 clinical medicine ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,medicine ,030212 general & internal medicine ,Myocardial infarction diagnosis ,Myocardial infarction ,medicine.symptom ,business ,Asymptomatic Diseases ,Cohort study - Abstract
OBJECTIVE To determine the prevalence and prognostic significance of unrecognized myocardial infarction (MI) by delayed-enhancement MRI (DE-MRI) in asymptomatic patients with diabetes. RESEARCH DESIGN AND METHODS In this prospective, two-center study of asymptomatic patients without known cardiac disease (n = 120), two prespecified cohorts underwent a research MRI: 1) a high-risk group with type 1 diabetes and chronic renal insufficiency (n = 50) and 2) an average-risk group with type 2 diabetes (n = 70). The primary end point was a composite of all-cause mortality and clinical MI. RESULTS Overall, the prevalence of unrecognized MI was 19% by DE-MRI (28% high-risk group and 13% average-risk group) and 5% by electrocardiography. During up to 5 years of follow-up with a total of 460 patient-years of follow-up, the rate of death/MI was markedly higher in patients with diabetes with (vs. without) unrecognized MI (all 44% vs. 7%, high-risk group 43% vs. 6%, and average-risk group 44% vs. 8%; all P < 0.01). After adjustment for Framingham risk score, left ventricular ejection fraction, and diabetes type, the presence of unrecognized MI by DE-MRI conferred an eightfold increase in risk of death/MI (95% CI 3.0–21.1, P < 0.0001). Addition of unrecognized MI to clinical indices significantly improved model discrimination for adverse events (integrated discrimination improvement = 0.156, P = 0.001). CONCLUSIONS Unrecognized MI is prevalent in asymptomatic patients with diabetes without a history of cardiac disease and confers a markedly increased risk of death and clinical MI.
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- 2019
17. Epicardial Surface Area of Infarction: A Stable Surrogate of Microvascular Obstruction in Acute Myocardial Infarction
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Sebastiaan C.A.M. Bekkers, Han W. Kim, Robert M. Judd, Martijn W. Smulders, Brenda Hayes, Casper W. H. Beijnink, Robin Nijveldt, Raymond J. Kim, Michele Parker, Yodying Kaolawanich, Lowie Van Assche, MUMC+: MA Med Staf Artsass Cardiologie (9), RS: Carim - Heart, RS: Carim - Blood, Cardiologie, MUMC+: MA Cardiologie (9), RS: Carim - B06 Imaging, and RS: Carim - H01 Clinical atrial fibrillation
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Male ,medicine.medical_specialty ,Poor prognosis ,PROGNOSIS ,OCCLUSION ,microvascular obstruction ,medicine.medical_treatment ,Vascular damage Radboud Institute for Health Sciences [Radboudumc 16] ,Magnetic Resonance Imaging, Cine ,Infarction ,heart transplantation ,ventricular remodeling ,Electrocardiography ,Coronary Circulation ,death ,Internal medicine ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,Ventricular remodeling ,DAMAGE ,Heart transplantation ,business.industry ,Microcirculation ,delayed-enhancement CMR ,Middle Aged ,NO-REFLOW PHENOMENON ,medicine.disease ,Coronary Vessels ,Pathophysiology ,ISCHEMIA ,myocardial infarction ,SIZE ,CARDIOVASCULAR MAGNETIC-RESONANCE ,Cardiology ,UPDATE ,Female ,Cardiology and Cardiovascular Medicine ,business ,Complication ,Pericardium - Abstract
Background: Microvascular obstruction (MO) is a pathophysiologic complication of acute myocardial infarction that portends poor prognosis; however, it is transient and disappears with infarct healing. Much remains unknown regarding its pathophysiology and whether there are predictors of MO that could function as stable surrogates. We tested for clinical and cardiovascular magnetic resonance predictors of MO to gain insight into its pathophysiology and to find a stable surrogate. Methods: Three hundred two consecutive patients from 2 centers underwent cardiovascular magnetic resonance within 2 weeks of first acute myocardial infarction. Three measures of infarct morphology: infarct size, transmurality, and a new index—the epicardial surface area (EpiSA) of full-thickness infarction—were quantified on delayed-enhancement cardiovascular magnetic resonance. Results: Considering all clinical characteristics, only measures of infarct morphology were independent predictors of MO. EpiSA was the strongest predictor of MO and provided incremental predictive value beyond that of infarct size and transmurality ( P P =0.045). Conclusions: The EpiSA of infarction is a novel index of infarct morphology which accurately predicts MO during the first 2 weeks of MI, but unlike MO, does not disappear with infarct healing. This index has potential as a stable surrogate of the presence of acute MO and may be useful as a predictor of adverse remodeling and outcome which is less dependent on the time window of patient assessment.
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- 2021
18. Comparison of magnetization transfer‐preparation and T2‐preparation for dark‐blood delayed‐enhancement imaging
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Enn-Ling Chen, Michele Parker, Han W. Kim, Clerio F. Azevedo, Raymond J. Kim, Wolfgang G Rehwald, Logan R Smith, Stephen Darty, Elizabeth R. Jenista, and David C. Wendell
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Adult ,Heart Ventricles ,Delayed enhancement ,Signal-To-Noise Ratio ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Left atrial ,medicine ,Quantitative assessment ,Humans ,Radiology, Nuclear Medicine and imaging ,Magnetization transfer ,Spectroscopy ,business.industry ,Signal Processing, Computer-Assisted ,Magnetic Resonance Imaging ,T2 preparation ,Blood ,medicine.anatomical_structure ,Ventricle ,Homogeneous ,Dark blood ,Molecular Medicine ,Artifacts ,business ,Nuclear medicine ,030217 neurology & neurosurgery - Abstract
Recently developed dark-blood techniques such as Flow-Independent Dark-blood DeLayed Enhancement (FIDDLE) allow simultaneous visualization of tissue contrast-enhancement and blood-pool suppression. Critical to FIDDLE is the magnetization preparation, which accentuates differences between myocardium and blood-pool. Here, we compared magnetization transfer (MT)-preparation and T2-preparation for use with FIDDLE. Variants of FIDDLE were developed with MT- or T2-preparation modules and tested in 35 patients (11 at 1.5 T, 24 at 3 T). Images were acquired with each FIDDLE variant in an interleaved fashion 10 minutes after gadolinium administration with otherwise identical acquisition parameters. Images were visually and quantitatively assessed for artifacts and differences in right ventricle to left ventricle (RV-to-LV) blood-pool suppression. Bright artifacts, reflecting incomplete blood-pool suppression, were frequently observed in the left atrium with T2-preparation FIDDLE at 1.5 and 3 T (82% and up to 100% of patients, respectively). MT-preparation FIDDLE resulted in fewer patients with artifacts (0% at 1.5 T, 22% at 3 T; P < .01). Left atrial blood-pool signal was significantly more homogeneous with MT-preparation than with T2-preparation at 1.5 and 3 T (P < .001 for all comparisons). Visibly different RV-to-LV blood-pool suppression was observed with T2-preparation in 36% of patients at 1.5 T and up to 94% at 3 T. In these patients, RV blood-pool signal was elevated, reducing the conspicuity of the myocardial-RV blood-pool border. Conversely, there were no visible differences in RV-to-LV blood-pool suppression with MT-preparation. Quantitative assessment of differences in blood-pool suppression and blood-pool artifacts was consistent with visual analyses. We conclude that for dark blood-blood delayed-enhancement imaging of the heart, MT-preparation results in fewer bright blood-pool artifacts and more uniform blood-pool suppression than T2-preparation.
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- 2020
19. Suppression of ghost artifacts arising from long T1 species in segmented inversion-recovery imaging
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Wolfgang G Rehwald, David C. Wendell, Han W. Kim, Enn-Ling Chen, Elizabeth R. Jenista, Michele Parker, Nayla H. Chaptini, and Raymond J. Kim
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Physics ,Artifact (error) ,medicine.diagnostic_test ,Magnetic resonance imaging ,Inversion recovery ,Steady-state free precession imaging ,030204 cardiovascular system & hematology ,equipment and supplies ,Signal ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Nuclear magnetic resonance ,medicine ,Radiology, Nuclear Medicine and imaging - Abstract
Purpose We demonstrate an improved segmented inversion-recovery sequence that suppresses ghost artifacts arising from tissues with long T1 ( > 1.5 s). Theory and Methods Long T1 species such as pericardial fluid can create bright ghost artifacts in segmented, inversion-recovery MRI because of oscillations in longitudinal magnetization between segments. A single dummy acquisition at the beginning of the sequence can reduce oscillations; however, its effectiveness in suppressing long T1 artifacts is unknown. In this study, we systematically evaluated several test sequences, including a prototype (saturation post-pulse readout to eliminate spurious signal: SPPRESS) in simulations, phantoms, and patients. Results SPPRESS reduced artifact signal 90% ± 25% and 74% ± 28% compared with Control and Single-Dummy methods in phantoms. SPPRESS performed well at 1.5 Tesla (T) and 3T, with steady-state free precession (SSFP) and fast low-angle shot (FLASH) readout, with conventional and phase-sensitive reconstruction, and over a range of physiologic heart rates. A review of 100 consecutive clinical cardiac MRI scans revealed large fluid collections (eg, regions with long T1) in 14% of patients. In a prospectively enrolled cohort of 16 patients with visible long T1 fluids, SPPRESS appreciably reduced artifacts in all cases compared with Control and Single-Dummy methods. Conclusion We developed and validated a new robust method, SPPRESS, for reducing artifacts due to long T1 species across a wide range of imaging and physiologic conditions. Magn Reson Med, 2016. © 2016 International Society for Magnetic Resonance in Medicine.
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- 2016
20. The Sonnet-Ballad
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NICK LANTZ, JAMAAL MAY, MICHELE PARKER RANDALL, VIRGINIA EUWER WOLFF, and TIMOTHY YU
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- 2019
21. Prognostic Value of Vasodilator Stress Cardiac Magnetic Resonance Imaging: A Multicenter Study With 48 000 Patient-Years of Follow-up
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Robert O. Bonow, Chetan Shenoy, John F. Heitner, Dany Debs, Raymond J. Kim, Elizabeth R. Jenista, Dipan J. Shah, Afshin Farzaneh-Far, Han W. Kim, Andrew Hughes, Jonathan W. Weinsaft, Igor Klem, Jean Ho, Preston Cargile, Michele Parker, Robert M. Judd, Venkateshwar Polsani, and Jiwon Kim
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Male ,medicine.medical_specialty ,Vasodilator Agents ,Myocardial Infarction ,Coronary Artery Disease ,030204 cardiovascular system & hematology ,Ventricular Function, Left ,Body Mass Index ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Interquartile range ,Cardiac magnetic resonance imaging ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,Medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,Aged ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Hazard ratio ,Correction ,Heart ,Stroke Volume ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Survival Analysis ,Predictive value of tests ,Cardiology ,Exercise Test ,Female ,Cardiology and Cardiovascular Medicine ,business ,Body mass index ,Social Security Death Index ,Follow-Up Studies - Abstract
Stress cardiac magnetic resonance imaging (CMR) is not widely used in current clinical practice, and its ability to predict patient mortality is unknown.To determine whether stress CMR is associated with patient mortality.Real-world evidence from consecutive clinically ordered CMR examinations. Multicenter study of patients undergoing clinical evaluation of myocardial ischemia. Patients with known or suspected coronary artery disease (CAD) underwent clinical vasodilator stress CMR at 7 different hospitals. An automated process collected data from the finalized clinical reports, deidentified and aggregated the data, and assessed mortality using the US Social Security Death Index.All-cause patient mortality.Of the 9151 patients, the median (interquartile range) patient age was 63 (51-70) years, 55% were men, and the median (interquartile range) body mass index was 29 (25-33) (calculated as weight in kilograms divided by height in meters squared). The multicenter automated process yielded 9151 consecutive patients undergoing stress CMR, with 48 615 patient-years of follow-up. Of these patients, 4408 had a normal stress CMR examination, 4743 had an abnormal examination, and 1517 died during a median follow-up time of 5.0 years. Using multivariable analysis, addition of stress CMR improved prediction of mortality in 2 different risk models (model 1 hazard ratio [HR], 1.83; 95% CI, 1.63-2.06; P .001; model 2: HR, 1.80; 95% CI, 1.60-2.03; P .001) and also improved risk reclassification (net improvement: 11.4%; 95% CI, 7.3-13.6; P .001). After adjustment for patient age, sex, and cardiac risk factors, Kaplan-Meier survival analysis showed a strong association between an abnormal stress CMR and mortality in all patients (HR, 1.883; 95% CI, 1.680-2.112; P .001), patients with (HR, 1.955; 95% CI, 1.712-2.233; P .001) and without (HR, 1.578; 95% CI, 1.235-2.2018; P .001) a history of CAD, and patients with normal (HR, 1.385; 95% CI, 1.194-1.606; P .001) and abnormal left ventricular ejection fraction (HR, 1.836; 95% CI, 1.299-2.594; P .001).Clinical vasodilator stress CMR is associated with patient mortality in a large, diverse population of patients with known or suspected CAD as well as in multiple subpopulations defined by history of CAD and left ventricular ejection fraction. These findings provide a foundational motivation to study the comparative effectiveness of stress CMR against other modalities.
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- 2019
22. Principal Perceptions of Superintendents: Using Motivating Language and Antecedents as a Predictor of Outcomes
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Michele Parker
- Published
- 2019
23. Dark-Blood Delayed-Enhancement MRI of Myocardial Infarction
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Elizabeth R. Jenista, Michele Parker, Christoph J Jensen, Enn-Ling Chen, Lowie Van Assche, David C. Wendell, Igor Klem, Han W. Kim, Peter Filev, Wolfgang G Rehwald, Raymond J. Kim, Robert M. Judd, and Anna Lisa Crowley
- Subjects
Adult ,medicine.medical_specialty ,Magnetic Resonance Spectroscopy ,Myocardial Infarction ,Contrast Media ,Pilot Projects ,Delayed enhancement ,030204 cardiovascular system & hematology ,Article ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Text mining ,Dogs ,Predictive Value of Tests ,Internal medicine ,Coronary Circulation ,medicine ,Organometallic Compounds ,Imaging diagnosis ,Animals ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Myocardial infarction ,Aged ,Tissue Survival ,business.industry ,Myocardium ,Clinical performance ,Reproducibility of Results ,Heart ,Middle Aged ,medicine.disease ,Infarct size ,Prognosis ,Magnetic Resonance Imaging ,Disease Models, Animal ,Case-Control Studies ,Dark blood ,cardiovascular system ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Cardiac magnetic resonance - Abstract
This study introduced and validated a novel flow-independent delayed enhancement technique that shows hyperenhanced myocardium while simultaneously suppressing blood-pool signal.The diagnosis and assessment of myocardial infarction (MI) is crucial in determining clinical management and prognosis. Although delayed enhancement cardiac magnetic resonance (DE-CMR) is an in vivo reference standard for imaging MI, an important limitation is poor delineation between hyperenhanced myocardium and bright LV cavity blood-pool, which may cause many infarcts to become invisible.A canine model with pathology as the reference standard was used for validation (n = 22). Patients with MI and normal controls were studied to ascertain clinical performance (n = 31).In canines, the flow-independent dark-blood delayed enhancement (FIDDLE) technique was superior to conventional DE-CMR for the detection of MI, with higher sensitivity (96% vs. 85%, respectively; p = 0.002) and accuracy (95% vs. 87%, respectively; p = 0.01) and with similar specificity (92% vs, 92%, respectively; p = 1.0). In infarcts that were identified by both techniques, the entire length of the endocardial border between infarcted myocardium and adjacent blood-pool was visualized in 33% for DE-CMR compared with 100% for FIDDLE. There was better agreement for FIDDLE-measured infarct size than for DE-CMR infarct size (95% limits-of-agreement, 2.1% vs. 5.5%, respectively; p 0.0001). In patients, findings were similar. FIDDLE demonstrated higher accuracy for diagnosis of MI than DE-CMR (100% [95% confidence interval [CI]: 89% to 100%] vs. 84% [95% CI: 66% to 95%], respectively; p = 0.03).The study introduced and validated a novel CMR technique that improves the discrimination of the border between infarcted myocardium and adjacent blood-pool. This dark-blood technique provides diagnostic performance that is superior to that of the current in vivo reference standard for the imaging diagnosis of MI.
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- 2017
24. Relationship of T2-Weighted MRI Myocardial Hyperintensity and the Ischemic Area-At-Risk
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Lowie Van Assche, W. Benjamin Wince, Lubna Bhatti, Wolfgang G Rehwald, Christoph J Jensen, Han W. Kim, Elizabeth R. Jenista, Raymond J. Kim, Michele Parker, David C. Wendell, Igor Klem, Robert M. Judd, Robert B. Jennings, Deneen Spatz, Enn-Ling Chen, and Anna Lisa Crowley
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Male ,Pathology ,Physiology ,Myocardial Infarction ,Infarction ,030204 cardiovascular system & hematology ,030218 nuclear medicine & medical imaging ,0302 clinical medicine ,Integrative Physiology ,Medicine ,Edema ,Myocardial infarction ,Prospective Studies ,Troponin T ,medicine.diagnostic_test ,Heart ,Organ Size ,Middle Aged ,Magnetic Resonance Imaging ,Microspheres ,medicine.anatomical_structure ,Cardiology ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Female ,Abnormality ,Cardiology and Cardiovascular Medicine ,MRI ,Adult ,Risk ,medicine.medical_specialty ,Endpoint Determination ,Diagnosis, Differential ,magnetic resonance ,03 medical and health sciences ,Coronary circulation ,Dogs ,Internal medicine ,Coronary Circulation ,Organometallic Compounds ,Animals ,Humans ,Aged ,Fluorescent Dyes ,business.industry ,Myocardium ,Magnetic resonance imaging ,medicine.disease ,Hyperintensity ,Histopathology ,business - Abstract
Supplemental Digital Content is available in the text., Rationale: After acute myocardial infarction (MI), delineating the area-at-risk (AAR) is crucial for measuring how much, if any, ischemic myocardium has been salvaged. T2-weighted MRI is promoted as an excellent method to delineate the AAR. However, the evidence supporting the validity of this method to measure the AAR is indirect, and it has never been validated with direct anatomic measurements. Objective: To determine whether T2-weighted MRI delineates the AAR. Methods and Results: Twenty-one canines and 24 patients with acute MI were studied. We compared bright-blood and black-blood T2-weighted MRI with images of the AAR and MI by histopathology in canines and with MI by in vivo delayed-enhancement MRI in canines and patients. Abnormal regions on MRI and pathology were compared by (a) quantitative measurement of the transmural-extent of the abnormality and (b) picture matching of contours. We found no relationship between the transmural-extent of T2-hyperintense regions and that of the AAR (bright-blood-T2: r=0.06, P=0.69; black-blood-T2: r=0.01, P=0.97). Instead, there was a strong correlation with that of infarction (bright-blood-T2: r=0.94, P
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- 2015
25. Breaking House
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MICHELE PARKER RANDALL
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- 2017
26. Sources of variability in quantification of cardiovascular magnetic resonance infarct size - reproducibility among three core laboratories
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Igor Klem, Lowie Van Assche, Håkan Arheden, Einar Heiberg, John D. Grizzard, Raymond J. Kim, Michele Parker, and Han W. Kim
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Gadolinium DTPA ,Male ,medicine.medical_specialty ,lcsh:Diseases of the circulatory (Cardiovascular) system ,Laboratory Proficiency Testing ,Partial volume ,Contrast Media ,Magnetic Resonance Imaging, Cine ,030204 cardiovascular system & hematology ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Image Interpretation, Computer-Assisted ,Organometallic Compounds ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Myocardial infarction ,Angiology ,Aged ,Automation, Laboratory ,Observer Variation ,Sweden ,Reproducibility ,Core (anatomy) ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Myocardium ,Research ,Reproducibility of Results ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,United States ,Sample size determination ,lcsh:RC666-701 ,Predictive value of tests ,Case-Control Studies ,ST Elevation Myocardial Infarction ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,Algorithms - Abstract
Background Acute myocardial infarct (AMI) size depicted by late gadolinium enhancement cardiovascular magnetic resonance (CMR) is increasingly used as an efficacy endpoint in randomized trials comparing AMI therapies. Infarct size is quantified using manual planimetry (MANUAL), visual scoring (VISUAL), or automated techniques using signal-intensity thresholding (AUTO). Although AUTO is considered the most reproducible, prior studies did not account for the subjective determination of endocardial/epicardial borders, which all methods require. For MANUAL and VISUAL, prior studies did not address how to treat intermediate signal intensities due to partial volume. Methods To assess sources of variability, AMI size was measured in 30 patients and 12 controls by 3 core-laboratories using 8 methods, each separated by more than 2 months time (n = 720 evaluations). The methods were: (1,2) AUTOSegment, AUTOFWHM (using Segment software or the full-width-at-half-maximum algorithm, respectively); (3,4) AUTO-UCSegment, AUTO-UCFWHM (user correction for endocardial border pixels, no-reflow, etc.); (5) MANUAL; (6) MANUAL-ISI (adjustment for intermediate signal-intensities); (7) VISUAL; (8) VISUAL-ISI. Results Mean infarct size varied between 16.8% and 27.2% of LV mass depending on method. Even automated techniques with no user interaction for infarct borders resulted in significant within-patient variability given the need to subjectively trace endocardial/epicardial contours. The coefficient-of-variation (CV) was 10.6% and 14.6% for AUTOSegment and AUTOFWHM, respectively. For manual and visual categories, reproducibility was improved when intermediate signal-intensities were considered (MANUAL-ISI vs MANUAL: CV = 8.3% vs 14.4%; p = 0.03; VISUAL-ISI vs VISUAL: CV = 8.4% vs 10.9%; p = 0.01). For AUTO-UCSegment, MANUAL-ISI, and VISUAL-ISI (best technique in each category) within-patient variability due to the quantification method was less than 10% of total variability, and the required sample sizes for detecting a 5% absolute difference in infarct size were 62, 63, and 62 patients, respectively. Conclusion Among CMR core-laboratories, an important source of variability in infarct size quantification is the subjective delineation of endocardial/epicardial borders. When intermediate signal intensities are considered in manual planimetry and visual scoring, reproducibility and impact on sample size are similar to automated techniques.
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- 2017
27. Stress Cardiac MR Imaging Compared with Stress Echocardiography in the Early Evaluation of Patients Who Present to the Emergency Department with Intermediate-Risk Chest Pain
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John F. Heitner, Michele Parker, Raymond J. Kim, Abhinav Chandra, Robert M. Judd, Igor Klem, Lowie Van Assche, James G. Jollis, Derek Rasheed, and Han W. Kim
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Male ,Chest Pain ,medicine.medical_specialty ,Contrast Media ,Coronary Disease ,Perfusion scanning ,Coronary Angiography ,Chest pain ,Risk Assessment ,Sensitivity and Specificity ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,Organometallic Compounds ,medicine ,Stress Echocardiography ,Humans ,Radiology, Nuclear Medicine and imaging ,Prospective cohort study ,Original Research ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Emergency department ,Middle Aged ,Magnetic Resonance Imaging ,Predictive value of tests ,Cardiology ,Female ,Radiology ,medicine.symptom ,Presentation (obstetrics) ,Emergency Service, Hospital ,business ,Echocardiography, Stress - Abstract
To compare the utility and efficacy of stress cardiac magnetic resonance (MR) imaging and stress echocardiography in an emergency setting in patients with acute chest pain (CP) and intermediate risk of coronary artery disease (CAD).Written informed consent was obtained from all patients. This HIPAA-compliant study was approved by the institutional review board for research ethics. Sixty patients without history of CAD presented to the emergency department with intermediate-risk acute CP and were prospectively enrolled. Patients underwent both stress cardiac MR imaging and stress echocardiography in random order within 12 hours of presentation. Stress imaging results were interpreted clinically immediately (blinded interpretation was performed months later), and coronary angiography was performed if either result was abnormal. CAD was considered significant if it was identified at angiography (narrowing50% ) or if a cardiac event (death or myocardial infarction) occurred during follow-up (mean, 14 months ± 5 [standard deviation]). McNemar test was used to compare the diagnostic accuracy of techniques.Stress cardiac MR imaging and stress echocardiography had similar specificity, accuracy, and positive and negative predictive values (92% vs 96%, 93% vs 88%, 67% vs 60%, and 100% vs 91%, respectively, for clinical interpretation; 90% vs 92%, 90% vs 88%, 58% vs 56%, and 98% vs 94%, respectively, for blinded interpretation). Stress cardiac MR imaging had higher sensitivity at clinical interpretation (100% vs 38%, P = .025), which did not reach significance at blinded interpretation (88% vs 63%, P = .31). However, multivariable logistic regression analysis showed stress cardiac MR imaging to be the strongest independent predictor of significant CAD (P = .002).In patients presenting to the emergency department with intermediate-risk CP, adenosine stress cardiac MR imaging performed within 12 hours of presentation is safe and potentially has improved performance characteristics compared with stress echocardiography. Online supplemental material is available for this article.
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- 2014
28. CMR Imaging With Rapid Visual T1 Assessment Predicts Mortality in Patients Suspected of Cardiac Amyloidosis
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Femida Gwadry-Sridhar, Ki-Young Kim, Dipan J. Shah, Han W. Kim, Nowell M. Fine, Robert M. Judd, James A. White, Manesh R. Patel, Raymond J. Kim, Wael AlJaroudi, Michele Parker, and David C. Wendell
- Subjects
medicine.medical_specialty ,Population ,030204 cardiovascular system & hematology ,Left ventricular hypertrophy ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Interquartile range ,Internal medicine ,medicine ,Clinical endpoint ,magnetic resonance imaging ,Radiology, Nuclear Medicine and imaging ,education ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Amyloidosis ,Hazard ratio ,amyloid ,Magnetic resonance imaging ,medicine.disease ,delayed enhancement ,3. Good health ,Cardiac amyloidosis ,Radiology Nuclear Medicine and imaging ,Cardiology ,business ,Cardiology and Cardiovascular Medicine - Abstract
ObjectivesThis study tested the diagnostic and prognostic utility of a rapid, visual T1 assessment method for identification of cardiac amyloidosis (CA) in a “real-life” referral population undergoing cardiac magnetic resonance for suspected CA.BackgroundIn patients with confirmed CA, delayed-enhancement cardiac magnetic resonance (DE-CMR) frequently shows a diffuse, global hyperenhancement (HE) pattern. However, imaging is often technically challenging, and the prognostic significance of diffuse HE is unclear.MethodsNinety consecutive patients referred for suspected CA and 64 hypertensive patients with left ventricular hypertrophy (LVH) were prospectively enrolled and underwent a modified DE-CMR protocol. After gadolinium administration a method for rapid, visual T1 assessment was used to identify the presence of diffuse HE during the scan, allowing immediate optimization of settings for the conventional DE-CMR that followed. The primary endpoint was all-cause mortality.ResultsAmong patients with suspected CA, 66% (59 of 90) demonstrated HE, with 81% (48 of 59) of these meeting pre-specified visual T1 assessment criteria for diffuse HE. Among hypertensive LVH patients, 6% (4 of 64) had HE, with none having diffuse HE. During 29 months of follow-up (interquartile range: 12 to 44 months), there were 50 (56%) deaths in patients with suspected CA and 4 (6%) in patients with hypertensive LVH. Multivariable analysis demonstrated that the presence of diffuse HE was the most important predictor of death in the group with suspected CA (hazard ratio: 5.5, 95% confidence interval: 2.7 to 11.0; p < 0.0001) and in the population as a whole (hazard ratio: 6.0, 95% confidence interval 3.0 to 12.1; p < 0.0001). Among 25 patients with myocardial histology obtained during follow-up, the sensitivity, specificity, and accuracy of diffuse HE in the diagnosis of CA were 93%, 70%, and 84%, respectively.ConclusionsAmong patients suspected of CA, the presence of diffuse HE by visual T1 assessment accurately identifies patients with histologically-proven CA and is a strong predictor of mortality.
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- 2014
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29. The assessment of atrial function by velocity-encoded magnetic resonance imaging
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Michele Parker, Peter J. Cawley, Jonathan W. Weinsaft, Joseph C. Greenfield, Manesh R. Patel, Michael Elliott, Raymond J. Kim, Igor Klem, Anna Lisa Crowley, Robert M. Judd, Charles Vu, and John F. Heitner
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Mitral regurgitation ,medicine.medical_specialty ,education.field_of_study ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Population ,Magnetic resonance imaging ,Computer analysis ,medicine.anatomical_structure ,Cardiac magnetic resonance imaging ,Mitral valve ,Internal medicine ,cardiovascular system ,medicine ,Cardiology ,cardiovascular diseases ,business ,Prospective cohort study ,education - Abstract
Introduction: The purpose of this study was to assess velocity-encoded cardiac magnetic resonance imaging (Ve-CMR) in a population of patients referred for cardiac magnetic resonance imaging (CMR), to determine the variability of atrial function, and to identify clinical parameters associated with left atrial function. Methods: This is a prospective study evaluating patients who were referred to our CMR center for a clinical CMR. Left atrial function was obtained via Ve-CMR thru-plane images across the mitral valve after acquiring 2 perpendicular in-plane images as “scouts”. The atrial function and mitral inflow were quantified by computer analysis (Argus, Siemens). Atrial function was defined as atrial contraction (A-wave) volume divided by total inflow volume. Left atrial volumes were calculated via computer analysis. Mitral regurgitation and left ventricular ejection fractions were assessed visually. Results: Thirty-nine patients, with mean age 56 +/- 10 years, were enrolled. The mean left atrial function was 22.9% +/-14.5%; the range in left atrial function was 0% - 57%. There was a significant positive correlation between atrial function and increased left ventricular ejection fraction (r = 0.44, P
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- 2013
30. Motion and flow insensitive adiabatic T2-preparation module for cardiac MR imaging at 3 tesla
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Igor Klem, Han W. Kim, Wolfgang G Rehwald, Raymond J. Kim, Elizabeth R. Jenista, Michele Parker, and Enn-Ling Chen
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Magnetization ,Nuclear magnetic resonance ,Image quality ,Coefficient of variation ,Radiology, Nuclear Medicine and imaging ,Blood flow ,Adiabatic process ,Imaging phantom ,Cardiac imaging ,Mathematics ,Weighting - Abstract
A versatile method for generating T2 -weighting is a T2 -preparation module, which has been used successfully for cardiac imaging at 1.5T. Although it has been applied at 3T, higher fields (B0 ≥ 3T) can degrade B0 and B1 homogeneity and result in nonuniform magnetization preparation. For cardiac imaging, blood flow and cardiac motion may further impair magnetization preparation. In this study, a novel T2 -preparation module containing multiple adiabatic B1 -insensitive refocusing pulses is introduced and compared with three previously described modules [(a) composite MLEV4, (b) modified BIR-4 (mBIR-4), and (c) Silver-Hoult-pair]. In the static phantom, the proposed module provided similar or better B0 and B1 insensitivity than the other modules. In human subjects (n = 21), quantitative measurement of image signal coefficient of variation, reflecting overall image inhomogeneity, was lower for the proposed module (0.10) than for MLEV4 (0.15, P < 0.0001), mBIR-4 (0.27, P < 0.0001), and Silver-Hoult-pair (0.14, P = 0.001) modules. Similarly, qualitative analysis revealed that the proposed module had the best image quality scores and ranking (both, P < 0.0001). In conclusion, we present a new T2 -preparation module, which is shown to be robust for cardiac imaging at 3T in comparison with existing methods.
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- 2012
31. Prevalence of regional and whole-heart viability in patients with myocardial akinesis consecutively enrolled from 4 US hospitals
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Dina Labib, Han W. Kim, Dipan J. Shah, Faisal Nabi, Igor Klem, Anna Lisa Crowley, Michele Parker, John F. Heitner, Robert M. Judd, Afshin Farzaneh-Far, and Raymond J. Kim
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Medicine(all) ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,business.industry ,medicine.disease ,Walking Poster Presentation ,Emergency medicine ,medicine ,Radiology, Nuclear Medicine and imaging ,In patient ,Medical emergency ,Cardiology and Cardiovascular Medicine ,business ,Angiology - Published
- 2016
32. Comparison of T2-preparation and magnetization-transfer preparation for black blood delayed enhancement
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Stephen Darty, Enn-Ling Chen, Han W. Kim, Wolfgang G Rehwald, Michele Parker, Elizabeth R. Jenista, David C. Wendell, and Raymond J. Kim
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Medicine(all) ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,Blood pool ,business.industry ,Black blood ,Left atrium ,Delayed enhancement ,030204 cardiovascular system & hematology ,T2 preparation ,Walking Poster Presentation ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Magnetization transfer ,Cardiology and Cardiovascular Medicine ,business ,Angiology - Published
- 2016
33. Flow-Independent Dark-blood DeLayed Enhancement (FIDDLE): validation of a novel black blood technique for the diagnosis of myocardial infarction
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Christoph J Jensen, Enn-Ling Chen, Raymond J. Kim, Wolfgang G Rehwald, Elizabeth R. Jenista, Han W. Kim, Lowie Van Assche, David C. Wendell, and Michele Parker
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Medicine(all) ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,business.industry ,Black blood ,Delayed enhancement ,Blood flow ,medicine.disease ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Animal model ,Internal medicine ,Dark blood ,Cardiology ,Oral Presentation ,Medicine ,Radiology, Nuclear Medicine and imaging ,In patient ,Radiology ,Myocardial infarction ,Cardiology and Cardiovascular Medicine ,business ,030217 neurology & neurosurgery ,Angiology - Abstract
Background A fundamental component of the CMR exam is contrast enhanced imaging, which is crucial for delineating diseased from normal tissue. Unfortunately, diseased tissue adjacent to vasculature often remains hidden since there is poor contrast between hyperenhanced tissue and bright blood-pool. Conventional black-blood double-IR methods are not a solution; these were not designed to function after contrast administration since they rely on the long native T1 of blood (~2s at 3T) and adequate blood flow within this time period. We introduce a novel Flow-Independent Dark-blood DeLayed Enhancement technique (FIDDLE) that allows visualization of tissue contrast-enhancement while suppressing blood-pool signal. We validate FIDDLE in an animal model of myocardial infarction (MI) and demonstrate feasibility in patients.
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- 2016
34. Safety of adenosine stress perfusion cardiac MRI in patients undergoing lung transplantation evaluation
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Igor Klem, Han W. Kim, Raymond J. Kim, Anna Lisa Crowley, Sung A Chang, Michele Parker, and Marco A Cordeiro
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Medicine(all) ,medicine.medical_specialty ,Radiological and Ultrasound Technology ,business.industry ,medicine.medical_treatment ,Adenosine stress ,medicine.disease ,Idiopathic pulmonary fibrosis ,Text mining ,Internal medicine ,Poster Presentation ,medicine ,Cardiology ,Lung transplantation ,Radiology, Nuclear Medicine and imaging ,In patient ,Radiology ,Cardiology and Cardiovascular Medicine ,Cardiac magnetic resonance ,business ,Perfusion ,Angiology - Published
- 2016
35. Accuracy of ECV imaging for the detection of subendocardial infarction - comparison with black blood delayed enhancement and pathology
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Raymond J. Kim, Dina Labib, David C. Wendell, Michele Parker, Han W. Kim, Elizabeth R. Jenista, S A Chang, Enn-Ling Chen, and Wolfgang G Rehwald
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Medicine(all) ,medicine.medical_specialty ,Pathology ,Radiological and Ultrasound Technology ,business.industry ,Black blood ,Transmural infarct ,Infarction ,Delayed enhancement ,medicine.disease ,Walking Poster Presentation ,Text mining ,Coronary occlusion ,Internal medicine ,medicine ,Cardiology ,Radiology, Nuclear Medicine and imaging ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Angiology - Published
- 2016
36. The Waiters.
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RANDALL, MICHELE PARKER
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- WAITERS, The (Short story), RANDALL, Michele Parker
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- 2021
37. LV Thrombus Detection by Routine Echocardiography
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Lowie Van Assche, Robert M. Judd, Raymond J. Kim, Rhoda Brosnan, Michele Parker, Han W. Kim, Jonathan W. Weinsaft, Igor Klem, Eric J. Velazquez, Dipan J. Shah, Chetan Shenoy, and Anna Lisa Crowley
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Echo (computing) ,Magnetic resonance imaging ,030204 cardiovascular system & hematology ,Left ventricular thrombus ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Radiology Nuclear Medicine and imaging ,Predictive value of tests ,Positive predicative value ,cardiovascular system ,medicine ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,030212 general & internal medicine ,Radiology ,Thrombus ,Cardiology and Cardiovascular Medicine ,business ,Prospective cohort study ,Chi-squared distribution - Abstract
Objectives This study sought to evaluate performance characteristics of routine echo for left ventricular thrombus (LVT). Background Although the utility of dedicated echocardiography (echo) for LVT is established, echo is widely used as a general test for which LVT is rarely the primary indication. We used delayed-enhancement cardiac magnetic resonance (DE-CMR) as a reference to evaluate LVT detection by routine echo. Methods Dedicated LVT assessment using DE-CMR was prospectively performed in patients with left ventricular systolic dysfunction. Echoes were done as part of routine clinical care. Echo and CMR were independently read for LVT and related indexes of LVT size, shape, and image quality/diagnostic confidence. Follow-up was done for embolic events and pathology validation of LVT. Results In this study, 243 patients had routine clinical echo and dedicated CMR within 1 week without intervening events. Follow-up supported DE-CMR as a reference standard, with >5-fold difference in endpoints between patients with versus without LVT by DE-CMR (p = 0.02). LVT prevalence was 10% by DE-CMR. Echo contrast was used in 4% of patients. Echo sensitivity and specificity were 33% and 91%, with positive and negative predictive values of 29% and 93%. Among patients with possible LVT as the clinical indication for echo, sensitivity and positive predictive value were markedly higher (60%, 75%). Regarding sensitivity, echo performance related to LVT morphology and mirrored cine-CMR, with protuberant thrombus typically missed when small (p ≤ 0.02). There was also a strong trend to miss mural thrombus irrespective of size (p = 0.06). Concerning positive predictive value, echo performance related to image quality, with lower diagnostic confidence scores for echoes read positive for LVT in discordance with DE-CMR compared with echoes concordant with DE-CMR (p Conclusions Routine echo with rare contrast use can yield misleading results concerning LVT. Echo performance is improved when large protuberant thrombus is present and when the clinical indication is specifically for LVT assessment.
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- 2011
38. Anatomic and clinical correlates of septal morphology in hypertrophic cardiomyopathy
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Raymond J. Kim, Andrew Wang, Brenda Hayes, Aslan T. Turer, Michele Parker, Joseph Kisslo, Anne Marie Valente, and Zainab Samad
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Adult ,Male ,medicine.medical_specialty ,Heart Ventricles ,Diastole ,Cardiomyopathy ,Magnetic Resonance Imaging, Cine ,Gadolinium ,Doppler echocardiography ,Ventricular Function, Left ,Muscle hypertrophy ,Sudden cardiac death ,Reference Values ,Cardiac magnetic resonance imaging ,Internal medicine ,Heart Septum ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Hemodynamics ,Hypertrophic cardiomyopathy ,Magnetic resonance imaging ,General Medicine ,Cardiomyopathy, Hypertrophic ,Middle Aged ,medicine.disease ,Echocardiography ,Multivariate Analysis ,cardiovascular system ,Cardiology ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Algorithms - Abstract
Aim The presence of septal hypertrophy in hypertrophic cardiomyopathy (HCM) is common. To date, there has been no accepted classification of septal morphology in HCM. Furthermore, the possible relationship between septal morphology and clinical features of HCM is undefined. Methods and results Seventy-five consecutive adult patients with HCM were enrolled. Septal morphologies were retrospectively categorized into one of four patterns of hypertrophy based on transthoracic echocardiography. Left ventricular diastolic function by Doppler echocardiography and late gadolinium enhancement (LGE) by magnetic resonance imaging were assessed in all patients. Patients were followed for a mean of 45 ± 32 months. Catenoid septum was the most common morphologic subtype (46 of 75, 61%), followed by simple sigmoid (22 of 75, 29%), neutral (4 of 75, 5%), and apical (3 of 75, 4%). Inter-observer reproducibility of septal classifications was high (κ = 0.95). Patients with the catenoid subtype presented at a younger age, had worse diastolic function, and high rates of LGE. The presence of catenoid septal morphology was independently associated with LGE in multivariable logistic regression analysis. Implantable cardioverter-defibrillator implantation for prevention of sudden cardiac death occurred only in patients with this septal morphology. Conclusion We propose a simple, reproducible classification system of patterns of septal hypertrophy in HCM. These patterns of hypertrophy are associated with significant differences in clinical, haemodynamic, and myocardial characteristics. Further studies are needed to evaluate the relationship between septal morphology and outcome or response to therapies in HCM.
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- 2010
39. The aorta wall of patients presenting to the emergency department with acute myocardial infarction by cardiac magnetic resonance
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Sorin J. Brener, Raymond J. Kim, Jonathan W. Weinsaft, John F. Heitner, Anna Lisa Crowley, Michele Parker, Peter J. Cawley, Geetha P. Bhumireddy, Michael D. Elliott, Robert M. Judd, Manesh R. Patel, and Igor Klem
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Adult ,Male ,medicine.medical_specialty ,Acute coronary syndrome ,medicine.medical_treatment ,Myocardial Infarction ,Aorta, Thoracic ,Chest pain ,Risk Assessment ,Angina Pectoris ,Coronary artery disease ,Predictive Value of Tests ,Risk Factors ,Internal medicine ,medicine.artery ,Diabetes Mellitus ,North Carolina ,medicine ,Humans ,Prospective Studies ,cardiovascular diseases ,Myocardial infarction ,Acute Coronary Syndrome ,Aged ,Cardiac catheterization ,Aorta ,business.industry ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Troponin ,Up-Regulation ,Asymptomatic Diseases ,cardiovascular system ,Cardiology ,Myocardial infarction complications ,Female ,Myocardial infarction diagnosis ,medicine.symptom ,Emergency Service, Hospital ,Cardiology and Cardiovascular Medicine ,business ,Biomarkers - Abstract
Inflammation has been shown to be a major component in the pathophysiology of acute coronary syndrome (ACS). In patients presenting with acute myocardial infarction (AMI), a critical component of the ACS spectrum, multiple coronary arteries are involved during this inflammatory process. In addition to the coronary vasculature, the inflammatory cascade has also been shown to affect the carotid arteries and possibly the aorta.To assess the involvement of the aorta during AMI by cardiac magnetic resonance (CMR).We prospectively evaluated the aortic wall by CMR in 123 patients. 78 patients were enrolled from the emergency department (ED), who presented with chest pain and were classified as either: (1) AMI: elevated troponin levels and typical chest pain or (2) non-cardiac chest pain (CP): negative troponins and a normal stress test or normal cardiac catheterization. We compared these 2 groups to a group of 45 asymptomatic diabetic patients. The descending thoracic aortic wall area (AWA) and maximal aortic wall thickness (AWT) were measured using a double inversion recovery T-2 weighted, ECG-gated, spin echo sequence by CMR.Patients with AMI were older, more likely to smoke, had a higher incidence of claudication, and had higher CRP levels. The AWA and maximal AWT were greater in patients who presented to the ED with ACS (2.11+/-0.17 mm(2), and 3.17+/-0.19 mm, respectively) than both patients presenting with non-cardiac CP (1.52+/-0.58 mm(2), p0.001; and 2.57+/-0.10 mm, p0.001) and the diabetic patients (1.38+/-0.58 mm(2), p0.001; and 2.30+/-0.131 mm, p0.001). The difference in the aortic wall characteristics remained significant after correcting for body mass index, hyperlipidemia, statins and C-reactive protein. There was no difference in maximal AWT or AWA between patients with non-cardiac CP and patients with diabetes.Patients with AMI have a significantly greater maximal aortic wall thickness and area compared to patients with non-cardiac CP. Longitudinal studies are needed to assess whether this increase is due to inflammation or a higher atherosclerotic burden.
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- 2010
40. Contrast-Enhanced Anatomic Imaging as Compared to Contrast-Enhanced Tissue Characterization for Detection of Left Ventricular Thrombus
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Michele Parker, Daniel G. Krauser, Troy M. LaBounty, Richard B. Devereux, Raymond J. Kim, Michael I Ross, Yi Wang, Matthew D. Cham, Mary J. Roman, Shant Manoushagian, Kirsten O Healy, Jonathan W. Weinsaft, and James K. Min
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Male ,medicine.medical_specialty ,Heart Diseases ,Heart Ventricles ,Myocardial Infarction ,Contrast Media ,Magnetic Resonance Imaging, Cine ,Sensitivity and Specificity ,cardiac magnetic resonance ,Article ,Ventricular Dysfunction, Left ,Predictive Value of Tests ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Registries ,cardiovascular diseases ,Myocardial infarction ,Thrombus ,Aged ,Heart Failure ,Observer Variation ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Stroke Volume ,Thrombosis ,Magnetic resonance imaging ,Stroke volume ,Middle Aged ,Left ventricular thrombus ,medicine.disease ,thrombus ,Echocardiography ,Radiology Nuclear Medicine and imaging ,cardiovascular system ,Myocardial infarction complications ,Female ,Radiology ,business ,Cardiology and Cardiovascular Medicine ,circulatory and respiratory physiology - Abstract
ObjectivesThis study sought to compare contrast-enhanced anatomic imaging and contrast-enhanced tissue characterization (delayed-enhancement cardiac magnetic resonance [DE-CMR]) for left ventricular (LV) thrombus detection.BackgroundContrast echocardiography (echo) detects LV thrombus based on anatomic appearance, whereas DE-CMR imaging detects thrombus based on tissue characteristics. Although DE-CMR has been validated as an accurate technique for thrombus, its utility compared with contrast echo is unknown.MethodsMultimodality imaging was performed in 121 patients at high risk for thrombus due to myocardial infarction or heart failure. Imaging included 3 anatomic imaging techniques for thrombus detection (contrast echo, noncontrast echo, cine-CMR) and a reference of DE-CMR tissue characterization. LV structural parameters were quantified to identify markers for thrombus and predictors of additive utility of contrast-enhanced thrombus imaging.ResultsTwenty-four patients had thrombus by DE-CMR. Patients with thrombus had larger infarcts (by DE-CMR), more aneurysms, and lower LV ejection fraction (by CMR and echo) than those without thrombus. Contrast echo nearly doubled sensitivity (61% vs. 33%, p < 0.05) and yielded improved accuracy (92% vs. 82%, p < 0.01) versus noncontrast echo. Patients who derived incremental diagnostic utility from DE-CMR had lower LV ejection fraction versus those in whom noncontrast echo alone accurately assessed thrombus (35 ± 9% vs. 42 ± 14%, p < 0.01), with a similar trend for patients who derived incremental benefit from contrast echo (p = 0.08). Contrast echo and cine-CMR closely agreed on the diagnosis of thrombus (κ = 0.79, p < 0.001). Thrombus prevalence was lower by contrast echo than DE-CMR (p < 0.05). Thrombus detected by DE-CMR but not by contrast echo was more likely to be mural in shape or, when apical, small in volume (p < 0.05).ConclusionsEcho contrast in high-risk patients markedly improves detection of LV thrombus, but does not detect a substantial number of thrombi identified by DE-CMR tissue characterization. Thrombi detected by DE-CMR but not by contrast echo are typically mural in shape or small in volume.
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- 2009
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41. Late conversion of tacrolimus to sirolimus in a prednisone-free immunosuppression regimen in renal transplant patients
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Joseph R. Leventhal, Michele Parker, Darshika Chhabra, Brian Cabral, Monica Grafals, and Lorenzo Gallon
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Transplantation ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Urology ,Renal function ,Immunosuppression ,Tacrolimus ,Surgery ,Calcineurin ,Regimen ,surgical procedures, operative ,Sirolimus ,medicine ,business ,medicine.drug ,Antibacterial agent - Abstract
Chhabra D, Grafals M, Cabral B, Leventhal J, Parker M, Gallon L. Late conversion of tacrolimus to sirolimus in a prednisone-free immunosuppression regimen in renal transplant patients. Clin Transplant 2009: DOI: 10.1111/j.1399-0012.2009.01047.x © 2009 John Wiley & Sons A/S. Abstract: Background: One of the most important causes of graft loss is chronic nephrotoxicity from calcineurin inhibitors. The aim of this study was to evaluate the feasibility and to assess the impact on rejection risk, graft loss and renal allograft function of converting patients from tacrolimus (Tac) to sirolimus (SRL) at one yr post-transplantation (Tx) using a prednisone-free immunosuppressive regimen. Methods: Two hundred fifty-five kidney transplant patients were induced with Alemtuzumab and maintained on a steroid-free regimen with Tac and mycophenolate mofetil. Thirty-seven stable patients (14%) were converted from Tac to SRL at one yr post-Tx. Results: The two groups were demographically similar. Mean post-tx follow-up was 2.8 ± 0.2 yr. Patient and graft survival were not statistically different. There was no significant difference in acute rejection episodes between the SRL and Tac groups (21% vs. 15%, p = 0.2). Calculated glomerular filtration rate (GFR), in the SRL group at 2.8 yr post-tx, was 69 ± 13 mL/min from the one month post-tx GFR of 53 ± 19 and 59 ± 23 mL/min from the one month post-tx GFR of 56 ± 21 mL/min in the Tac group. Conclusions: Using a prednisone-free regimen, the conversion of Tac to SRL at one yr post-Tx was not associated with an increased risk of acute rejection or graft loss.
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- 2009
42. Development of BK Nephropathy in Recipients of Simultaneous Pancreas-Kidney Transplantation
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Valentina Stosor, Michael G. Ison, Dixon B. Kaufman, and Michele Parker
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medicine.medical_specialty ,Antibodies, Neoplasm ,medicine.medical_treatment ,Urology ,Antibodies, Monoclonal, Humanized ,Single Center ,Nephropathy ,chemistry.chemical_compound ,Postoperative Complications ,medicine ,Animals ,Humans ,Alemtuzumab ,Antilymphocyte Serum ,Retrospective Studies ,Polyomavirus Infections ,Transplantation ,Creatinine ,business.industry ,Antibodies, Monoclonal ,Immunosuppression ,Viral Load ,medicine.disease ,Kidney Transplantation ,Survival Analysis ,Surgery ,chemistry ,BK Virus ,Cytomegalovirus Infections ,Pancreas Transplantation ,Rabbits ,business ,Immunosuppressive Agents ,medicine.drug ,Cidofovir ,Kidney disease - Abstract
Background. BK nephropathy (BKVN) is a significant cause of graft dysfunction in kidney transplant recipients, but its course in simultaneous pancreas-kidney (SPK) recipients is less well studied. The presence of dual organs limits the ability to reduce maintenance immunosuppression, typically the first intervention in the management of BKVN. Methods. A single center, retrospective review was conducted of 205 SPK transplants performed from January 1, 2000 to April 30, 2006. Results. The 5-year actuarial cumulative rate of BKVN was 5.6%. Diagnosis occurred at a median of 20 months after transplant; mean serum creatinine was 2.6, and geometric mean BK serum viral load was 709,274 copies/mL at diagnosis. There was no statistical difference in the cumulative rate according to the use of induction therapy: rabbit antilymphocyte globulin (5-year rate 6.8%, 4/59), alemtuzumab (5-year rate 5.1%, 5/146). Treatment consisted of immunosuppression reduction and half received cidofovir. Eight of nine kidney allografts eventually failed, but all patients retained pancreatic allograft function. Conclusions. BKVN occurs in 5.6% of SPK recipients. There is no difference in the cumulative rate of BKVN between patients who received alemtuzumab or rabbit antilymphocyte globulin.
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- 2009
43. Detection of Left Ventricular Thrombus by Delayed-Enhancement Cardiovascular Magnetic Resonance
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Manesh R. Patel, Dipan J. Shah, Rhoda Brosnan, Han W. Kim, Eric J. Velazquez, John F. Heitner, Raymond J. Kim, Robert M. Judd, Anna Lisa Crowley, Jonathan W. Weinsaft, Charles Steenbergen, Olga James, Igor Klem, and Michele Parker
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medicine.medical_specialty ,Population ,030204 cardiovascular system & hematology ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Myocardial scarring ,medicine ,cardiovascular diseases ,Thrombus ,education ,education.field_of_study ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Left ventricular thrombus ,medicine.disease ,3. Good health ,Circulatory system ,cardiovascular system ,Etiology ,Radiology ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,circulatory and respiratory physiology - Abstract
Objectives This study sought to assess the prevalence and markers of left ventricular (LV) thrombus among patients with systolic dysfunction. Background Prior studies have yielded discordant findings regarding prevalence and markers of LV thrombus. Delayed-enhancement cardiovascular magnetic resonance (DE-CMR) identifies thrombus on the basis of tissue characteristics rather than just anatomical appearance and is potentially highly accurate. Methods Prevalence of thrombus by DE-CMR was determined in 784 consecutive patients with systolic dysfunction (left ventricular ejection fraction [LVEF] Results Among this at-risk population (age 60 ± 14 years; LVEF 32 ± 11%), DE-CMR detected thrombus in 7% (55 patients) and cine-CMR in 4.7% (37 patients, p Conclusions In a broad cross section of patients with systolic dysfunction, thrombus prevalence was 7% by DE-CMR and included small intracavitary and small or large mural thrombus missed by cine-CMR. Prevalence increased with worse LVEF, ischemic etiology, and increased myocardial scarring.
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- 2008
44. Impact of Anemia after Renal Transplantation on Patient and Graft Survival and on Rate of Acute Rejection
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Monica Grafals, Anton I. Skaro, Darshika Chhabra, Lorenzo Gallon, and Michele Parker
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Adult ,Graft Rejection ,Male ,medicine.medical_specialty ,Time Factors ,Epidemiology ,Anemia ,medicine.medical_treatment ,chemical and pharmacologic phenomena ,Critical Care and Intensive Care Medicine ,Risk Assessment ,Gastroenterology ,Hemoglobins ,Risk Factors ,hemic and lymphatic diseases ,Internal medicine ,Diabetes mellitus ,Odds Ratio ,Renal Transplantation ,medicine ,Humans ,Kidney transplantation ,Dialysis ,Retrospective Studies ,Transplantation ,Kidney ,Aspirin ,Proportional hazards model ,business.industry ,Incidence ,Graft Survival ,Middle Aged ,medicine.disease ,Kidney Transplantation ,Surgery ,Treatment Outcome ,surgical procedures, operative ,medicine.anatomical_structure ,Nephrology ,Female ,business ,medicine.drug - Abstract
Background and objectives: The impact of posttransplantation anemia on patient survival, renal allograft survival, and rate of acute rejection is not known. Design, setting, participants, & measurements: A total of 1023 patients who underwent kidney transplantation at one center from January 1992 through June 2003 were retrospectively analyzed. Posttransplantation anemia was defined as mean hemoglobin
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- 2008
45. Value of Cardiovascular Magnetic Resonance Stress Perfusion Testing for the Detection of Coronary Artery Disease in Women
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Holger Vogelsberg, Igor Klem, Srivani R. Ambati, Eva Maria Kispert, Han W. Kim, John F. Heitner, Simon Greulich, Udo Sechtem, Michele Parker, Christian Bruch, Raymond J. Kim, and Robert M. Judd
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Adenosine ,Stress testing ,Infarction ,030204 cardiovascular system & hematology ,Coronary Angiography ,Chest pain ,Severity of Illness Index ,030218 nuclear medicine & medical imaging ,Coronary artery disease ,0302 clinical medicine ,CAD ,Prospective Studies ,education.field_of_study ,medicine.diagnostic_test ,Myocardial Perfusion Imaging ,Middle Aged ,3. Good health ,Europe ,Radiology Nuclear Medicine and imaging ,Cardiology ,Female ,women ,Radiology ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,stress CMR ,Perfusion ,Algorithms ,medicine.medical_specialty ,Population ,Magnetic Resonance Imaging, Cine ,Sensitivity and Specificity ,Angina Pectoris ,03 medical and health sciences ,Sex Factors ,Predictive Value of Tests ,Coronary Circulation ,Internal medicine ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,education ,Aged ,business.industry ,Coronary Stenosis ,Stroke Volume ,Magnetic resonance imaging ,medicine.disease ,United States ,Stenosis ,ROC Curve ,Exercise Test ,Women's Health ,business - Abstract
Objectives We wanted to assess the value of cardiovascular magnetic resonance (CMR) stress testing for evaluation of women with suspected coronary artery disease (CAD). Background A combined perfusion and infarction CMR examination can accurately diagnose CAD in the clinical setting in a mixed gender population. Methods We prospectively enrolled 147 consecutive women with chest pain or other symptoms suggestive of CAD at 2 centers (Duke University Medical Center, Robert-Bosch-Krankenhaus). Each patient underwent a comprehensive clinical evaluation, a CMR stress test consisting of cine rest function, adenosine-stress and rest perfusion, and delayed-enhancement CMR infarction imaging, and X-ray coronary angiography within 24 h. The components of the CMR test were analyzed visually both in isolation and combined using a pre-specified algorithm. Coronary artery disease was defined as stenosis ≥70% on quantitative analysis of coronary angiography. Results Cardiovascular magnetic resonance imaging was completed in 136 females (63.0 ± 11.1 years), 37 (27%) women had CAD on coronary angiography. The combined CMR stress test had a sensitivity, specificity, and accuracy of 84%, 88%, and 87%, respectively, for the diagnosis of CAD. Diagnostic accuracy was high at both sites (Duke University Medical Center 82%, Robert-Bosch-Krankenhaus 90%; p = 0.18). The accuracy for the detection of CAD was reduced when intermediate grade stenoses were included (82% vs. 87%; p = 0.01 compared the cutoff of stenosis ≥50% vs. ≥70%). The sensitivity was lower in women with single-vessel disease (71% vs. 100%; p = 0.06 compared with multivessel disease) and small left ventricular mass (69% vs. 95%; p = 0.04 for left ventricular mass ≤97 g vs. >97 g). The latter difference was even more significant after accounting for end-diastolic volumes (70% vs. 100%; p = 0.02 for left ventricular mass indexed to end-diastolic volume ≤1.15 g/ml vs. >1.15 g/ml). Conclusions A multicomponent CMR stress test can accurately diagnose CAD in women. Detection of CAD in women with intermediate grade stenosis, single-vessel disease, and with small hearts is challenging.
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- 2008
46. Direct En Face Imaging of Secundum Atrial Septal Defects by Velocity-Encoded Cardiovascular Magnetic Resonance in Patients Evaluated for Possible Transcatheter Closure
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Raymond J. Kim, Louise Thomson, J. Kevin Harrison, Michele Parker, Peter J. Cawley, Jonathan W. Weinsaft, Robert M. Judd, John F. Heitner, Anna Lisa Crowley, and Han W. Kim
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Adult ,Male ,Cardiac Catheterization ,medicine.medical_specialty ,Septum secundum ,Magnetic Resonance Imaging, Cine ,Severity of Illness Index ,Heart Septal Defects, Atrial ,Atrial septal defects ,Young Adult ,Aneurysm ,Predictive Value of Tests ,medicine.artery ,Internal medicine ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,In patient ,Oximetry ,Sinus (anatomy) ,Aged ,Aorta ,Atrial Septum ,medicine.diagnostic_test ,business.industry ,Patient Selection ,Hemodynamics ,Magnetic resonance imaging ,Equipment Design ,Middle Aged ,medicine.disease ,Treatment Outcome ,medicine.anatomical_structure ,Pulmonary artery ,cardiovascular system ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business ,Echocardiography, Transesophageal - Abstract
Background— Atrial septal defect (ASD) flow can be measured indirectly by velocity-encoded cardiovascular magnetic resonance (veCMR) of the pulmonary artery and aorta. Imaging the secundum ASD en face could potentially enable direct flow measurement and provide valuable information about ASD size, shape, location, and proximity to other structures. Methods and Results— Forty-four patients referred for possible transcatheter ASD closure underwent a comprehensive standard evaluation, including transesophageal and/or intracardiac echocardiography and invasive oximetry. CMR was performed in parallel and included direct en face veCMR after an optimal double-oblique imaging plane was determined that accounted for ASD flow direction and cardiac-cycle interatrial septal motion. ASD flow measured by direct en face veCMR correlated better with invasive oximetry than indirect (pulmonary artery and aorta) veCMR ( r =0.80 versus r =0.66). Additionally, 95% limits of agreement were narrower (�3.9 versus �5.1 L/min). En face veCMR determined that defects usually were eccentrically shaped (major/minor axis length >1.5) rather than circular, with 16% having extreme eccentricity (major/minor >2.0). Overall, ASD size by both veCMR and intracardiac echocardiography correlated with final device size; however, in small to medium defects (2 ) and extremely eccentric defects, veCMR correlated better with final device size than did intracardiac echocardiography. Importantly, CMR identified additional information in 9 patients (20%) that altered clinical management. Specifically, en face veCMR detected additional defects (n=3), large ASD with insufficient rim tissue (n=2), and sinus venosus defect with anomalous pulmonary vein (n=1). Cine and/or morphological imaging detected interrupted inferior vena cava (n=2) and sinus of Valsalva aneurysm (n=1). Conclusions— En face veCMR with an optimized imaging plane can determine ASD flow, size, and morphology. CMR provided information incremental to comprehensive standard evaluation that altered clinical management in 20% of patients.
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- 2008
47. Performance of Delayed-Enhancement Magnetic Resonance Imaging With Gadoversetamide Contrast for the Detection and Assessment of Myocardial Infarction
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Alicia M. Napoli, John Carson Allen, James H. Wible, Jennifer C. Lee, Michael D. Elliott, Raymond J. Kim, Timothy S. E. Albert, Michele Parker, and Robert M. Judd
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Adult ,Male ,medicine.medical_specialty ,Myocardial Infarction ,Contrast Media ,Sensitivity and Specificity ,law.invention ,Precontrast ,Double-Blind Method ,Randomized controlled trial ,law ,Physiology (medical) ,Multicenter trial ,Organometallic Compounds ,Humans ,Medicine ,Myocardial infarction ,Aged ,Gadoversetamide ,medicine.diagnostic_test ,business.industry ,Patient Selection ,Magnetic resonance imaging ,Middle Aged ,South America ,Image Enhancement ,medicine.disease ,Magnetic Resonance Imaging ,United States ,Europe ,Acute Disease ,Chronic Disease ,Female ,Myocardial infarction diagnosis ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,Perfusion ,medicine.drug - Abstract
Background— The identification and assessment of myocardial infarction (MI) are important for therapeutic and prognostic purposes, yet current recommended diagnostic strategies have significant limitations. We prospectively tested the performance of delayed-enhancement magnetic resonance imaging (MRI) with gadolinium-based contrast for the detection of MI in an international, multicenter trial. Methods and Results— Patients with their first MI were enrolled in an acute (≤16 days after MI; n=282) or chronic (17 days to 6 months; n=284) arm and then randomized to 1 of 4 doses of gadoversetamide: 0.05, 0.1, 0.2, or 0.3 mmol/kg. Standard delayed-enhancement MRI was performed before contrast (control) and 10 and 30 minutes after gadoversetamide. For blinded analysis, precontrast and postcontrast MRIs were randomized and then scored for enhanced regions by 3 independent readers not associated with the study. The infarct-related artery perfusion territory was scored from x-ray angiograms separately. In total, 566 scans were performed in 26 centers using commercially available scanners from all major US/European vendors. All scans were included in the analysis. The sensitivity of MRI for detecting MI increased with rising dose of gadoversetamide ( P P P Conclusions— Gadoversetamide-enhanced MRI using doses of ≥0.2 mmol/kg is effective in the detection and assessment of both acute and chronic MI. This study represents the first multicenter trial designed to evaluate an imaging approach for detecting MI.
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- 2008
48. Long-Term Renal Transplant Function in Recipient of Simultaneous Kidney and Pancreas Transplant Maintained With Two Prednisone-Free Maintenance Immunosuppressive Combinations: Tacrolimus/Mycophenolate Mofetil Versus Tacrolimus/Sirolimus
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Johan Winoto, Michele Parker, Dixon B. Kaufman, Darshika Chhabra, Joseph R. Leventhal, and Lorenzo Gallon
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Adult ,Graft Rejection ,Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Urology ,Renal function ,Tacrolimus ,Mycophenolic acid ,Cohort Studies ,medicine ,Humans ,Retrospective Studies ,Sirolimus ,Transplantation ,Thymoglobulin ,business.industry ,Graft Survival ,Panel reactive antibody ,Immunosuppression ,Middle Aged ,Mycophenolic Acid ,medicine.disease ,Kidney Transplantation ,Survival Analysis ,Surgery ,Treatment Outcome ,Drug Therapy, Combination ,Female ,Pancreas Transplantation ,business ,Immunosuppressive Agents ,Follow-Up Studies ,Kidney disease ,medicine.drug - Abstract
Background It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). Methods In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. Results Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. Conclusions Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.
- Published
- 2007
49. Sources of variability in quantification of CMR infarct size and their impact on sample size calculations - reproducibility among three core laboratories
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Igor Klem, Håkan Arheden, Han W. Kim, Michele Parker, Einar Heiberg, John D. Grizzard, Lowie Van Assche, Raymond J. Kim, and Galen S. Wagner
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Medicine(all) ,medicine.medical_specialty ,Reproducibility ,Radiological and Ultrasound Technology ,business.industry ,Partial volume ,Infarct size ,computer.software_genre ,law.invention ,Randomized controlled trial ,law ,Sample size determination ,Poster Presentation ,Visual scoring ,Medicine ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Data mining ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,computer ,Angiology - Abstract
Background Infarct size is increasingly used as an efficacy endpoint in randomized trials comparing acute myocardial infarct (AMI) therapies. Infarct size, depicted by delayedenhancement-CMR, is quantified using manual planimetry (MANUAL), visual scoring (VISUAL), or automated techniques using signal-intensity thresholding to define infarct borders (AUTO). Although AUTO is considered the most reproducible, prior studies did not account for the subjective determination of endocardial/epicardial borders, which all methods require. For MANUAL and VISUAL, prior studies have not explicitly defined how to treat intermediate signal-intensities due to partial volume. We wanted to assess sources of variability among 6 methods in quantification of AMI size, and illustrate the significance of these findings on sample size calculations for clinical trials.
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- 2015
50. Delayed Enhancement Magnetic Resonance Imaging Predicts Response to Cardiac Resynchronization Therapy in Patients With Intraventricular Dyssynchrony
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Raymond Yee, Andrew D. Krahn, George J. Klein, Allan C. Skanes, Xiaping Yuan, James A. White, Maria Drangova, and Michele Parker
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Male ,Time Factors ,Systole ,medicine.medical_treatment ,Cardiac Output, Low ,Myocardial Infarction ,Cardiac resynchronization therapy ,Medical Records ,Cicatrix ,QRS complex ,Predictive Value of Tests ,Interquartile range ,Ventricular Dysfunction ,medicine ,Humans ,Myocardial infarction ,Aged ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Cardiac Pacing, Artificial ,Magnetic resonance imaging ,Middle Aged ,Image Enhancement ,medicine.disease ,Magnetic Resonance Imaging ,Treatment Outcome ,Echocardiography ,Heart failure ,Circulatory system ,Female ,Nuclear medicine ,business ,Cardiology and Cardiovascular Medicine - Abstract
Objectives We evaluated the ability of delayed enhancement magnetic resonance imaging (DE-MRI) to predict clinical response to cardiac resynchronization therapy (CRT). Background Cardiac resynchronization therapy reduces morbidity and mortality in selected heart failure patients. However, up to 30% of patients do not have a response. We hypothesized that scar burden on DE-MRI predicts response to CRT. Methods The DE-MRI was performed on 28 heart failure patients undergoing CRT. Patients with QRS ≥120 ms, left ventricular ejection fraction ≤35%, New York Heart Association functional class II to IV, and dyssynchrony ≥60 ms were studied. Baseline and 3-month clinical follow-up, wall motion, 6-min walk, and quality of life assessment were performed. The DE-MRI was performed 10 min after 0.20 mmol/kg intravenous gadolinium. Scar measured by planimetry was correlated with response criteria. Results Twenty-three patients completed the protocol (mean age 64.9 ± 11.7 years), with 12 (52%) having a history of myocardial infarction. Thirteen (57%) patients met response criteria. Percent total scar was significantly higher in the nonresponse versus response group (median and interquartile range of 24.7% [18.1 to 48.7] vs. 1.0% [0.0 to 8.7], p = 0.0022) and predicted nonresponse by receiver-operating characteristic analysis (area = 0.94). At a cutoff value of 15%, percent total scar provided a sensitivity and specificity of 85% and 90%, respectively, for clinical response to CRT. Similarly, septal scar ≤40% provided a 100% sensitivity and specificity for response. Regression analysis showed linear correlations between percent total scar and change in each of the individual response criteria. Conclusions The DE-MRI accurately predicted clinical response to CRT. This technique offers unique information in the assessment of patients referred for CRT.
- Published
- 2006
- Full Text
- View/download PDF
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