16 results on '"Leon Frazin"'
Search Results
2. Application of a Novel Two-Dimensional Echocardiographic Calcium Quantification Method to Assess All Severities of Aortic Stenosis
- Author
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Kevin Desai, Brody Slostad, Aamir Twing, Hema Krishna, Leon Frazin, and Mayank Kansal
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Echocardiography ,Aortic Valve ,Multidetector Computed Tomography ,Humans ,Radiology, Nuclear Medicine and imaging ,Calcium ,Aortic Valve Stenosis ,Cardiology and Cardiovascular Medicine ,Severity of Illness Index ,Retrospective Studies - Abstract
Aortic valve (AV) calcification (AVC) is a strong predictor of aortic stenosis (AS) severity. The two-dimensional AVC (2D-AVC) ratio, a gain-independent ratio composed of the average pixel density of the AV and the aortic annulus, has previously shown strong correlations with two-dimensional (2D) echocardiographic hemodynamic parameters for severe AS and AVC by cardiac computed tomography. We hypothesize that the 2D-AVC ratio correlates with hemodynamic parameters in all severities of AS.A total of 285 patients with a normal AV (n = 49), aortic sclerosis (n = 75), or mild (n = 38), moderate (n = 72), or severe (n = 51) AS undergoing 2D echocardiography were retrospectively evaluated, and the 2D-AVC ratios were correlated to mean AV gradient, peak AV velocity, AV area, and dimensionless index. The 2D-AVC ratios of various AS severities were compared against each other via area under the curve (AUC) analysis.The 2D-AVC ratio is strongly correlated with mean AV gradient (r = 0.79, P .0001) and peak AV velocity (r = 0.78, P .0001). There was moderate correlation with the AV area (r = -0.58, P .0001) and dimensionless index (r = -0.67, P .0001) across all AS severities. The 2D-AVC ratio also distinguished nonmoderate AS (mild AS + normal AV) from moderate or greater (moderate + severe) AS (AUC = 0.93) and moderate versus severe AS (AUC = 0.88).The 2D-AVC ratio exhibits moderate to strong correlation with 2D echocardiographic hemodynamic parameters across all severities of AS.
- Published
- 2022
3. A quantitative gain-independent assessment of the left atrial appendage as a method of thromboembolic risk stratification
- Author
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Brody Slostad, Kevin Lee, Michael Trybula, Sreenivas Konda, Victor Macrinici, Leon Frazin, and Mayank Kansal
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Male ,Atrial Fibrillation ,Humans ,Radiology, Nuclear Medicine and imaging ,Atrial Appendage ,Female ,Middle Aged ,Risk Assessment ,Echocardiography, Transesophageal ,Aged ,Retrospective Studies - Abstract
Visual assessment of the left atrial appendage (LAA) by echocardiography for the presence of thrombus is inherently qualitative. However, whether quantitative assessments can provide increased value over qualitative assessment has not been thoroughly examined.One hundred and thirty-eight patients (mean age 59 ± 13 years, 70% male) undergoing transesophageal echocardiography prior to pulmonary vein isolation or electrical cardioversion were retrospectively studied. LAA were examined by two expert readers and identified as thrombus, sludge, spontaneous echocardiograph contrast, or normal. LAA were then separately examined to calculate a gain-independent ratio between the average pixel density of the LAA cavity and that of the LAA wall (C/W ratio).C/W ratio was significantly related with qualitative LAA analysis (p 0.0001) and with thromboembolic events (OR 1.60, 95% CI 1.095-2.347, p = 0.02). The C/W ratio (AUC 0.73, 95% CI 0.60-0.86) was a reliable predictor for future thromboembolic events when compared to expert reader LAA assessment (Expert Reader 1 AUC = 0.72, 95% CI 0.53-0.90; Expert Reader 2 AUC = 0.69).The C/W ratio may be a complementary method to adjudicate thromboembolic risk in patients with AF that is readily quantifiable at time of TEE.
- Published
- 2021
4. Quantitative analysis of spectral Doppler clicks in assessment of aortic stenosis
- Author
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Brent White, Daniel Gonzalez, Leon Frazin, Weili Zheng, Sean Wessel, Ali A. Sovari, and Sreenivas Konda
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Male ,Aortic valve ,Cardiac Catheterization ,medicine.medical_specialty ,Heart Ventricles ,medicine.medical_treatment ,Spectral doppler ,030204 cardiovascular system & hematology ,Severity of Illness Index ,03 medical and health sciences ,symbols.namesake ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,030212 general & internal medicine ,Lead (electronics) ,Aged ,Retrospective Studies ,Cardiac catheterization ,business.industry ,Reproducibility of Results ,Aortic Valve Stenosis ,Gold standard (test) ,medicine.disease ,Echocardiography, Doppler ,Intensity (physics) ,Stenosis ,medicine.anatomical_structure ,Cardiology ,symbols ,Female ,Cardiology and Cardiovascular Medicine ,business ,Doppler effect ,Follow-Up Studies - Abstract
OBJECTIVES This study was performed to evaluate an additional echocardiographic spectral Doppler marker, which would identify severe aortic stenosis (AS). BACKGROUND Echocardiography is most commonly utilized to assess AS and has been validated against invasive measurements. However, the data obtained are not always in agreement, leaving a conundrum regarding the true severity of AS and can lead to other diagnostic procedures. This highlights the importance of improved noninvasive diagnostic techniques. METHODS Forty-eight indeterminate cases of calcific AS that had been previously evaluated by both echocardiography and cardiac catheterization were included in the study, using cardiac catheterization as the gold standard for calculation of aortic valve area (AVA). The intensity of opening and closing of the aortic valve, represented by bright vertical deflections on the CW spectral waveform, was quantified using ImageJ software to generate pixel intensity histograms to create opening and closing click (OC and CC) ratios. These ratios were compared with echocardiographic variables and catheterization AVA. RESULTS Thirty-five patients were found to have severe AS and 13 patients were found to have nonsevere AS, as assessed by cardiac catheterization. CC ratio was found to be a significant predictor of severe AS with an OR 0.024 (95% CI: 0.002-0.378, P = .0079). Adding CC to a model using standard echocardiographic parameters resulted in significant improvement in the C-statistic (0.693 to 0.835, P = .0134). CONCLUSIONS An additional Doppler marker measuring the aortic valve CC ratio has been found to improve detection of severe AS.
- Published
- 2019
5. A Novel Two-Dimensional Echocardiography Method to Objectively Quantify Aortic Valve Calcium and Predict Aortic Stenosis Severity
- Author
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Elliott M. Groves, Aamir Twing, Leon Frazin, Alex J. Auseon, Brody Slostad, Mayank M Kansal, Kevin Lee, and Colin C. Hubbard
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Aortic valve ,Male ,medicine.medical_specialty ,Short axis ,Hemodynamics ,Aortic calcification ,Severity of Illness Index ,Internal medicine ,medicine ,Humans ,Cardiac skeleton ,Aged ,Retrospective Studies ,business.industry ,Two dimensional echocardiography ,Calcinosis ,Aortic Valve Stenosis ,medicine.disease ,Stenosis ,medicine.anatomical_structure ,Parasternal line ,Echocardiography ,Aortic Valve ,cardiovascular system ,Cardiology ,Calcium ,Female ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies - Abstract
Aortic valve calcium (AVC) is a strong predictor of aortic stenosis (AS) severity and is typically calculated by multidetector computed tomography (MDCT). We propose a novel method using pixel density quantification software to objectively quantify AVC by two-dimensional (2D) transthoracic echocardiography (TTE) and distinguish severe from non-severe AS. A total of 90 patients (mean age 76 ± 10 years, 75% male, mean AV gradient 32 ± 11 mmHg, peak AV velocity 3.6 ± 0.6 m/s, AV area (AVA) 1.0 ± 0.3 cm2, dimensionless index (DI) 0.27 ± 0.08) with suspected severe aortic stenosis undergoing 2D echocardiography were retrospectively evaluated. Parasternal short axis aortic valve views were used to calculate a gain-independent ratio between the average pixel density of the entire aortic valve in short axis at end diastole and the average pixel density of the aortic annulus in short axis (2D-AVC ratio). The 2D-AVC ratio was compared to echocardiographic hemodynamic parameters associated with AS, MDCT AVC quantification, and expert reader interpretation of AS severity based on echocardiographic AVC interpretation. The 2D-AVC ratio exhibited strong correlations with mean AV gradient (r = 0.72, p
- Published
- 2021
6. A NOVEL 2D ECHOCARDIOGRAPHY METHOD TO PREDICT ALL SEVERITIES OF AORTIC STENOSIS
- Author
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Kevin Desai, Aamir Twing, Brody Slostad, Leon Frazin, and Mayank Kansal
- Subjects
Cardiology and Cardiovascular Medicine - Published
- 2022
7. A NOVEL 2D ECHOCARDIOGRAPHY METHOD TO OBJECTIVELY QUANTIFY AORTIC VALVE CALCIUM AND PREDICT AORTIC STENOSIS SEVERITY
- Author
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Elliott M. Groves, Aamir Twing, Colin C. Hubbard, Leon Frazin, Mayank M Kansal, Kevin Lee, and Brody Slostad
- Subjects
Stenosis ,medicine.medical_specialty ,2d echocardiography ,business.industry ,Internal medicine ,medicine ,Cardiology ,Aortic calcification ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business - Published
- 2021
8. TCT-356 Coronary Artery Axial Deformation in Native Compared With Stented Arteries
- Author
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Mladen I. Vidovich, Logan S. Schwarzman, Leon Frazin, Mayank M Kansal, and Decebal Griza
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medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Internal medicine ,medicine ,Cardiology ,Cardiology and Cardiovascular Medicine ,business ,Axial deformation ,Artery - Published
- 2019
9. Should the Celiac Artery Be Used as an Anatomical Marker for the Descending Thoracic Aorta During Transesophageal Echocardiography?
- Author
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Leon Frazin, Nikhil Jariwala, and Li Zhou
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Reproducibility of Results ,Aorta, Thoracic ,Computed tomography ,030204 cardiovascular system & hematology ,Aortic disease ,03 medical and health sciences ,0302 clinical medicine ,Celiac Artery ,030202 anesthesiology ,Celiac artery ,medicine.artery ,medicine ,Feasibility Studies ,Humans ,Thoracic aorta ,Radiology, Nuclear Medicine and imaging ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,human activities ,Echocardiography, Transesophageal - Abstract
Background Transesophageal echocardiography (TEE) is a pivotal tool for diagnosis of aortic diseases. However, there are no suitable anatomical markers to describe location of disease in the descending thoracic aorta. In the past, we have used distance from the dental incisors to report location of disease, but this has no anatomical relevance. Our recent data comparing TEE and computed tomography (CT) have shown that the celiac artery is an accurate anatomical marker where disease is described as distance relative to the celiac artery. This study was designed to determine whether utilization of the celiac artery as an anatomical marker with TEE is practically feasible. Methods A clinical trial was performed at the University of Illinois at Chicago and the Jesse Brown VA Medical Center. A total of 160 patients referred for TEE were consecutively enrolled over a period of 18 months. Results The celiac artery was visualized in 97% of the patients. Conclusions The celiac artery is a reliable anatomical marker with TEE and should be routinely used to locate disease in the descending thoracic aorta.
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- 2015
10. Prolonged Transesophageal Echocardiography Use in the ICU
- Author
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Ramona Nicolau, Vijay Krishnamoorthy, David E. Schwartz, Leon Frazin, and Mehmet S. Ozcan
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medicine.medical_specialty ,Fulminant hepatic failure ,business.industry ,Intensive care ,Psychological intervention ,Medicine ,Hemodynamics ,Management Science and Operations Research ,Critical Care and Intensive Care Medicine ,Critical Care Nursing ,business ,Intensive care medicine ,human activities - Abstract
Transesophageal echocardiography (TEE) has gained increasing popularity in the operating room and intensive care settings. The use of TEE can often times diagnose pathology that is missed by transthoracic echocardiography (TTE); in addition, it can be used as a guide to continuously monitor a patient’s hemodynamics, along with observing the direct cardiac effects of fluid and vasopressor therapy. We present a case of acute fulminant hepatic failure in the ICU, where TEE allowed a rapid diagnosis. We performed prolonged TEE monitoring (72 hours) of the patient to monitor the patient’s response to therapeutic interventions. We also discuss the diagnostic and therapeutic implications of prolonged TEE placement in the ICU. In addition, particular strategies to optimize the benefit and minimize the risk of this exciting, yet underutilized, technology are discussed.
- Published
- 2011
11. Transesophageal Echocardiography of the Descending Thoracic Aorta: Establishing an Accurate Anatomic Marker Using the Celiac Artery
- Author
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John Connolly, F.A.C.C. Leon Frazin M.D., Samip Vasaiwala, and F.A.C.C. Mladen I. Vidovich M.D.
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medicine.medical_specialty ,Aorta ,medicine.diagnostic_test ,business.industry ,Computed tomography ,Aortic disease ,Celiac artery ,medicine.artery ,medicine ,Thoracic aorta ,Radiology, Nuclear Medicine and imaging ,Radiology ,Ct findings ,Cardiology and Cardiovascular Medicine ,business ,human activities - Abstract
Objective: We performed transesophageal echocardiography (TEE) and computed tomography (CT) on patients with aortic pathology to describe a more anatomically coherent marker on TEE studies by using the celiac artery as a reference. Background: As there are no anatomic markers for the eight-vertebrae long descending thoracic aorta, aortic disease (AD) is routinely reported as a distance from the dental incisors in TEE studies. This method does not provide an anatomically accurate location of AD relative to recognizable anatomy. Methods: Ten patients referred for contrast CT and TEE for evaluation of embolic events were studied. Twenty-seven focal aortic lesions found on TEE were measured relative to their distance from the celiac artery. The agreement among the two methods of quantification of aortic lesions from the celiac artery was assessed by univariate regression analysis and by the Bland–Altman method. Difference in the mean values between the two groups was analyzed by paired t-test. Results: The P value for the two-tailed t-test for the difference between the two modalities was 0.122. The Pearson coefficient for comparison of CT and TEE data was 0.98. The coefficient of determination for TEE versus CT data was 0.96. Conclusions: The TEE CA reference marker proves to be an accurate method for localizing disease in the descending thoracic aorta relative to CT findings. Reporting of aortic disease relative to this marker is more clinically applicable than the current method of measurement. The CA reference marker should be routinely reported in TEE studies to enhance the diagnosis of aortic disease. (Echocardiography 2010;27:1093-1097)
- Published
- 2010
12. Cardiac Tamponade on the Edge
- Author
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Leon Frazin, Mayank M Kansal, and Kavita Krishnasamy
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Adult ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Hematopoietic stem cell transplantation ,Doppler echocardiography ,Pericardial effusion ,Pericardial Effusion ,Diagnosis, Differential ,Electrocardiography ,Internal medicine ,Cardiac tamponade ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,medicine.diagnostic_test ,business.industry ,Myelodysplastic syndromes ,Pulsus paradoxus ,Hematopoietic Stem Cell Transplantation ,Pericardiocentesis ,medicine.disease ,Echocardiography, Doppler ,Cardiac Tamponade ,Radiography ,Leukemia, Myeloid, Acute ,Myelodysplastic Syndromes ,Cardiology ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business - Published
- 2015
13. Transesophageal echocardiography of the descending thoracic aorta: establishing an accurate anatomic marker using the celiac artery
- Author
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Samip, Vasaiwala, Mladen I, Vidovich, John, Connolly, and Leon, Frazin
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Aged, 80 and over ,Male ,Celiac Artery ,Aortic Diseases ,Humans ,Aorta, Thoracic ,Female ,Image Enhancement ,Echocardiography, Transesophageal ,Aged - Abstract
We performed transesophageal echocardiography (TEE) and computed tomography (CT) on patients with aortic pathology to describe a more anatomically coherent marker on TEE studies by using the celiac artery as a reference.As there are no anatomic markers for the eight-vertebrae long descending thoracic aorta, aortic disease (AD) is routinely reported as a distance from the dental incisors in TEE studies. This method does not provide an anatomically accurate location of AD relative to recognizable anatomy.Ten patients referred for contrast CT and TEE for evaluation of embolic events were studied. Twenty-seven focal aortic lesions found on TEE were measured relative to their distance from the celiac artery. The agreement among the two methods of quantification of aortic lesions from the celiac artery was assessed by univariate regression analysis and by the Bland-Altman method. Difference in the mean values between the two groups was analyzed by paired t-test.The P value for the two-tailed t-test for the difference between the two modalities was 0.122. The Pearson coefficient for comparison of CT and TEE data was 0.98. The coefficient of determination for TEE versus CT data was 0.96.The TEE CA reference marker proves to be an accurate method for localizing disease in the descending thoracic aorta relative to CT findings. Reporting of aortic disease relative to this marker is more clinically applicable than the current method of measurement. The CA reference marker should be routinely reported in TEE studies to enhance the diagnosis of aortic disease.
- Published
- 2010
14. Mobile Ascending Aortic Atheroma Diagnosed by Transesophageal Echocardiography as Source of Peripheral Vascular Embolism
- Author
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Jason W. Glowney and Leon Frazin
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Adult ,Male ,medicine.medical_specialty ,medicine.artery ,Internal medicine ,Ascending aorta ,VASCULAR EMBOLISM ,Embolism, Air ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Medical history ,Computed tomography angiography ,Peripheral Vascular Diseases ,medicine.diagnostic_test ,business.industry ,Arterial Embolization ,Aortic Valve Stenosis ,Atherosclerosis ,medicine.disease ,Peripheral ,Atheroma ,cardiovascular system ,Cardiology ,Radiology ,Differential diagnosis ,Cardiology and Cardiovascular Medicine ,business ,Echocardiography, Transesophageal - Abstract
Complex aortic atheromas are an important differential diagnosis to consider in evaluating sources of arterial embolization. Diagnosis of the embolic source is an essential first step, so treatment can then be initiated to prevent further reoccurrence. We report the case of a 36-year-old man, without significant medical history, who presented to the University of Illinois at Chicago with peripheral vascular embolism to the lower extremities. Computed tomography with contrast angiography and transthoracic echocardiography failed to reveal a source of the thromboembolism. A complex mobile atheroma was discovered in the ascending aorta during transesophageal echocardiography. The case presented is noteworthy when considering the following: the relative rarity of complex atheromas of the ascending aorta, the young age of the patient with no history of atherosclerotic disease, and the failure of computed tomography angiography to reveal the embolic source despite literature supporting high sensitivities for aortic plaque detection compared with transesophageal echocardiography.
- Published
- 2009
15. Various types of systolic clicks in patients with muscular subaortic stenosis
- Author
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Aida Nunez, Aldo A. Luisada, Leon Frazin, and Achala Singhal
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Male ,medicine.medical_specialty ,Adolescent ,Systole ,Hemodynamics ,Electrocardiography ,Internal medicine ,otorhinolaryngologic diseases ,medicine ,Humans ,In patient ,cardiovascular diseases ,Aged ,Heart Murmurs ,business.industry ,Ventricular wall ,Phonocardiography ,Stroke Volume ,Cardiomyopathy, Hypertrophic ,medicine.disease ,Myocardial Contraction ,Systolic murmur ,Stenosis ,Carotid pulse ,Heart Sounds ,cardiovascular system ,Cardiology ,MUSCULAR SUBAORTIC STENOSIS ,Female ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Heart Auscultation - Abstract
Four clinical cases of subaortic hypertrophic muscular stenosis are discussed. All four, in addition to a loud systolic murmur, had a loud systolic click. However, the timing of the click and its relationship to the phase of the carotid pulse were different in each case varying from close to medium and to distant (or midsystolic). The comparison of the sound tracing with the carotid tracing demonstrated that, in each case, a sudden change in acceleration was taking place. In one, the click coincided with the onset of the carotid upstroke; in another, with the first peak of the carotid pulse; in the third, with the trough between first and second peak of the pulse; in the last, with a sudden drop of the pulse at mid-systole caused by sudden obstruction to flow. It is concluded that the clicks were caused by rapid changes of acceleration resulting from the abnormal aortic ejection. Thus, the study of the carotid pulse and of the sound tracing are important for a non-invasive diagnosis together with the echo study of the septum and ventricular wall.
- Published
- 1985
16. Definition of myocardial perfusion by continuous infusion of krypton-81m
- Author
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John M. Moran, Henry S. Loeb, James E. Gindler, Rolf M. Gunnar, Leon Frazin, Lewis W. Mayron, Ervin Kaplan, and Arnold M. Friedman
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Radioisotopes ,business.industry ,Krypton ,chemistry.chemical_element ,Collateral Circulation ,Collateral circulation ,Coronary Vessels ,Perfusion ,Catheter ,Dogs ,chemistry ,Coronary occlusion ,Occlusion ,Infusion pump ,Medicine ,Animals ,Television ,Cardiology and Cardiovascular Medicine ,Nuclear medicine ,business ,Radionuclide Imaging ,Reactive hyperemia ,Monitoring, Physiologic - Abstract
Krypton-81m, a radionuclide emitting a 190 kev gamma ray, has a half-life of 13 seconds. It is a radioisotope of an inert water-soluble noble gas and is produced at a constant rate by spontaneous decay of rubidium-81 in an 81Rb-81mKr generator-delivery system. Delivery is through a minibore Teflon catheter that can be threaded through a standard no. 7 or 8F angiographic catheter. The generator is eluted by 5 percent dextrose-in-water, delivered by infusion pump at 1.5 ml/min, and the eluate is infused intraarterially directly into any organ. Delivery and decay reach equilibrium within 2 minutes, producing a heterogeneous distribution that is proportional to the perfusibility of the tissue concerned and the time required to reach it. The ultrashort half-life of the radionuclide rapidly eliminates activity when delivery ceases; thus, experiments can be sequentially repeated at brief intervals. The radiation hazard for easily imaged doses is negligible. Preliminary studies in open chest dogs were visualized by scintillation camera, stored on digital data disk, processed, and displayed in dual channel, dual color mode on a video system. Images of myocardial perfusion defined relative levels of perfusion, collateral circulation between coronary arterial branches, equilibrium time of diffusible perfusion of the myocardium, focal defects in induced occlusion, collateral circulation to occlusion, and reactive hyperemia after release of induced coronary occlusion. The system and technique appear applicable to human subjects.
- Published
- 1976
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