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Purpose: The aim of this study was to evaluate the feasibility of attenuation correction (AC) for cardiac 18F-labelled fluorodeoxyglucose (FDG) positron emission tomography (PET) using MR-based attenuation maps. Methods: We included 23 patients with no known cardiac history undergoing whole-body FDG PET/CT imaging for oncological indications on a PET/CT scanner using time-of-flight (TOF) and subsequent whole-body PET/MR imaging on an investigational hybrid PET/MRI scanner. Data sets from PET/MRI (with and without TOF) were reconstructed using MR AC and semi-quantitative segmental (20-segment model) myocardial tracer uptake (per cent of maximum) and compared to PET/CT which was reconstructed using CT AC and served as standard of reference. Results: Excellent correlations were found for regional uptake values between PET/CT and PET/MRI with TOF (n = 460 segments in 23 patients; r = 0.913; p

OBJECTIVES: This study sought to develop a clinical model that identifies patients with and without high-risk coronary artery disease (CAD). BACKGROUND: Although current clinical models help to estimate a patient's pre-test probability of obstructive CAD, they do not accurately identify those patients with and without high-risk coronary anatomy. METHODS: Retrospective analysis of a prospectively collected multinational coronary computed tomographic angiography (CTA) cohort was conducted. High-risk anatomy was defined as left main diameter stenosis >= 50%, 3-vessel disease with diameter stenosis >= 70%, or 2-vessel disease involving the proximal left anterior descending artery. Using a cohort of 27,125, patients with a history of CAD, cardiac transplantation, and congenital heart disease were excluded. The model was derived from 24,251 consecutive patients in the derivation cohort and an additional 7,333 nonoverlapping patients in the validation cohort. RESULTS: The risk score consisted of 9 variables: age, sex, diabetes, hypertension, current smoking, hyperlipidemia, family history of CAD, history of peripheral vascular disease, and chest pain symptoms. Patients were divided into 3 risk categories: low (= 18 points). The model was statistically robust with area under the curve of 0.76 (95% confidence interval [CI]: 0.75 to 0.78) in the derivation cohort and 0.71 (95% CI: 0.69 to 0.74) in the validation cohort. Patients who scored = 18 points had a high specificity of 99.3% and a positive likelihood ratio (8.48). In the validation group, the prevalence of high-risk CAD was 1% in patients with = 18 points. CONCLUSIONS: We propose a scoring system, based on clinical variables, that can be used to identify patients at high and low pre-test probability of having high-risk CAD. Identification of these populations may detect those who may benefit from a trial of medical therapy and those who may benefit most from an invasive strategy. (C) 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

A reduction in left ventricular apical tracer uptake (apical thinning) is frequently observed in myocardial perfusion imaging (MPI), yet its cause remains a matter of debate, particularly in perfusion emission tomography (PET). This analysis sought to determine whether apical thinning in PET-MPI is attributable to true anatomical thinning of the left ventricular apical myocardium.We retrospectively analyzed 57 patients without any history or signs of apical myocardial infarction who underwent rest PET-MPI with 13N-ammonia and contrast-enhanced cardiac computed tomography (CT). Semi-quantitative normalized percent apical 13N-ammonia uptake at rest, myocardial blood flow (MBF), and k2 wash-out rate constants were compared to apical myocardial wall thickness measurements derived from CT and base-to-apex gradients were calculated. Apical thinning was found in 93% of patients and in 74% when analysis of normalized apical tracer uptake was confined to end-systole. No significant correlation was found between apical myocardial thickness and apical tracer uptake (r = - 0.080, P = .553), MBF (r = - 0.211, P = .115), or k2 wash-out rate (r = - 0.023, P = .872), nor between apical myocardial thickness and any gradients. A statistically significant but small difference in apical myocardial thickness was observed in patients with moderately to severely reduced apical tracer uptake vs patients with normal to mildly reduced uptake (4.3 ± 0.7 mm vs 4.7 ± 0.7 mm; P = .043).Apical thinning is a highly prevalent finding during 13N-ammonia PET-MPI that is not solely attributable to true anatomical apical wall thickness or the partial volume effect. Other factors that yet need to be identified seem to have a more prominent impact.

As the second term of our commitment to Journal begins, we, the editors, would like to reflect on a few topics that have relevance today. These include prognostication and paradigm shifts; Serial testing: How to handle data? Is the change in perfusion predictive of outcome and which one? Ischemia-guided therapy: fractional flow reserve vs perfusion vs myocardial blood flow; positron emission tomography (PET) imaging using Rubidium-82 vs N-13 ammonia vs F-18 Flurpiridaz; How to differentiate microvascular disease from 3-vessel disease by PET? The imaging scene outside the United States, what are the differences and similarities? Radiation exposure; Special issues with the new cameras? Is attenuation correction needed? Are there normal databases and are these specific to each camera system? And finally, hybrid imaging with single-photon emission tomography or PET combined with computed tomography angiography or coronary calcium score. We hope these topics are of interest to our readers.

In 30% of patients with brain metastasis (BM), neurological symptoms are the first clinical manifestation of systemic malignancy, referred to as BM from cancer of unknown primary site (BM-CUPS). Here, we define the diagnostic value ofWe screened 565 patients operated for BM at the University Hospital Zurich and identified 64 patients with BM-CUPS with data on both FDG-PET/CT and contrast-enhanced chest/abdomen computed tomography (CT) available at BM diagnosis. A cohort of 125 patients with BM-CUPS from Lille and Vienna was used for validation.FDG-PET/CT was not superior to chest/abdomen CT in localising the primary lesion in the discovery cohort, presumably because most primary tumours were lung cancers. However, FDG-PET/CT identified additional lesions suspicious of extracranial metastases in 27 of 64 patients (42%). The inclusion of FDG-PET/CT findings shifted the graded prognostic assessment (GPA) score from 3 with CT alone to 2.5 for PET/CT (p = 3.8 × 10Lung cancers are the most common primary tumour in BM-CUPS; accordingly, CT alone shows similar overall sensitivity for detecting the primary tumour as FDG-PET/CT. Yet, FDG-PET/CT improves the accuracy of staging by detecting more metastases, reflected by decreased GPA scores and decreased predicted survival. Therefore, randomised trials on patients with BM should standardise methods of staging, notably when stratifying for GPA.

Evidence to date on the unique female determinants of cardiovascular risk is inadequate. Positron Emission Tomography (PET) is considered to have the highest accuracy for the assessment of myocardial perfusion in patients with suspected coronary artery disease (CAD), but its long-term prognostic accuracy in women has not been established.A total of 619 consecutive patients (138 women, mean age 60.0 ± 11.8 years) underwent clinically indicatedDuring follow-up, 271 patients had at least one cardiac event, including 64 cardiac deaths and 33 nonfatal myocardial infarctions. In both women and men, abnormal myocardial perfusion was associated with reduced event-free survival (log rank p 0.001). In women, abnormal myocardial perfusion was associated with a higher risk of a worse outcome than in men (adjusted HR 4.1, 95% CI 1.8-9.0 in women; HR 2.4, 95% CI 1.5-3.8 in men; pWhile perfusion findings in

In light of growing cardiovascular mortality rates observed in young women, sexual dimorphism in cardiac autonomic nervous control is gaining increasing attention. Heart rate responses to adenosine mirror autonomic activity and may carry important prognostic information.Hemodynamic changes during adenosine stress were retrospectively analysed in a propensity-matched cohort of 1932 consecutive patients undergoing myocardial perfusion single-photon-emission computed tomography (MPI-SPECT). Heart rate (HR) and systolic blood pressure (SBP) increased during adenosine infusion (P 0.001). The increase in SBP and HR (heart rate reserve, HRR), was significantly more pronounced in women compared with men (P 0.05). Patients ≤ 55 years had a higher HRR compared with patients 55 years (46.8% vs 37.5%, P = 0.015). Women ≤ 55 years with a reversible perfusion defect on MPI-SPECT exhibited the highest HRR (89.2%), while age-matched men showed a blunted HR response to adenosine (26.4%, P = 0.01). Accordingly, age and an interaction term of female sex and increased HRR were identified as significant predictors of myocardial ischemia in a multiple regression analysis (OR 1.4, 95% CI 1.02-1.9, P = 0.038).HRR during adenosine infusion is influenced by age and sex. Our data suggest a stronger, sympathetic-driven, hemodynamic response to adenosine in younger women with myocardial ischemia.

Sensitive visualization of recurrent prostate cancer foci is a challenge in patients with early biochemical recurrence (EBR). The recently established 68Ga-PSMA-11 PET/CT has significantly improved the detection rate with published values of up to 55% for patients with a serum PSA concentration between 0.2–0.5 ng/mL. The increased soft tissue contrast in the pelvis using simultaneous 68Ga-PSMA-11 PET/MRI might further improve the detection rate in patients with EBR and low PSA values over PET/CT. We retrospectively analyzed a cohort of 56 consecutive patients who underwent a 68Ga-PSMA-11 PET/MRI for biochemical recurrence in our institution between April and December 2016 with three readers. Median PSA level was 0.99 ng/mL (interquartile range: 3.1 ng/mL). Detection of PSMA-positive lesions within the prostate fossa, local and distant lymph nodes, bones, or visceral organs was recorded. Agreement among observers was evaluated with Fleiss’s kappa (k). Overall, in 44 of 56 patients (78.6%) PSMA-positive lesions were detected. In four of nine patients (44.4%) with a PSA 2.0 ng/mL, suspicious lesions were detected. The overall interreader agreement for cancer detection was excellent (κ = 0.796, CI 0.645–0.947). Our data show that 68Ga-PSMA-11 PET/MRI has a high detection rate for recurrent prostate cancer even at very low PSA levels

Aims: Iterative reconstruction (IR) algorithms allow for a significant reduction in radiation dose of coronary computed tomography angiography (CCTA). We performed a head-to-head comparison of adaptive statistical IR (ASiR) and model-based IR (MBIR) algorithms to assess their impact on quantitative image parameters and diagnostic accuracy for submillisievert CCTA. Methods and results: CCTA datasets of 91 patients were reconstructed using filtered back projection (FBP), increasing contributions of ASiR (20, 40, 60, 80, and 100%), and MBIR. Signal and noise were measured in the aortic root to calculate signal-to-noise ratio (SNR). In a subgroup of 36 patients, diagnostic accuracy of ASiR 40%, ASiR 100%, and MBIR for diagnosis of coronary artery disease (CAD) was compared with invasive coronary angiography. Median radiation dose was 0.21 mSv for CCTA. While increasing levels of ASiR gradually reduced image noise compared with FBP (up to - 48%, P

ObjectivesThis study sought to assess clinical outcomes associated with the novel Coronary Artery Disease-Reporting and Data System (CAD-RADS) scores used to standardize coronary computed tomography angiography (CTA) reporting and their potential utility in guiding post-coronary CTA care.BackgroundClinical decision support is a major focus of health care policies aimed at improving guideline-directed care. Recently, CAD-RADS was developed to standardize coronary CTA reporting and includes clinical recommendations to facilitate patient management after coronary CTA.MethodsIn the multinational CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry, 5,039 patients without known coronary artery disease (CAD) underwent coronary CTA and were stratified by CAD-RADS scores, which rank CAD stenosis severity as 0 (0%), 1 (1% to 24%), 2 (25% to 49%), 3 (50% to 69%), 4A (70% to 99% in 1 to 2 vessels), 4B (70% to 99% in 3 vessels or≥50% left main), or 5(100%). Kaplan-Meier and multivariable Cox models were used to estimate all-cause mortality or myocardial infarction (MI). Receiver-operating characteristic (ROC) curves were used to compare CAD-RADS to the Duke CAD Index and traditional CAD classification. Referrals to invasive coronary angiography (ICA) after coronary CTA were also assessed.ResultsCumulative 5-year event-free survival ranged from 95.2% to 69.3% for CAD-RADS 0 to 5 (p< 0.0001). Higher scores were associated with elevations in event risk (hazard ratio: 2.46 to 6.09; p< 0.0001). The ROC curve for prediction of death or MI was 0.7052 for CAD-RADS, which was noninferior to the Duke Index (0.7073; p= 0.893) and traditional CAD classification (0.7095; p= 0.783). ICA rates were 13% for CAD-RADS 0 to 2, 66% for CAD-RADS 3, and 84% for CAD-RADS≥4A. For CAD-RADS 3, 58% of all catheterizations occurred within the first 30 days of follow-up. In apatient subset with available medication data, 57% of CAD-RADS 3 patients who received 30-day ICA were either asymptomatic or not receiving antianginal therapy at baseline, whereas only 32% had angina and were receiving medical therapy.ConclusionsCAD-RADS effectively identified patients at risk for adverse events. Frequent ICA use was observed among patients without severe CAD, many of whom were asymptomatic or not taking antianginal drugs. Incorporating CAD-RADS into coronary CTA reports may provide a novel opportunity to promote evidence-based care post-coronary CTA.

The aging brain is characterized by an increased presence of neurodegenerative and vascular pathologies. However, there is substantial variation regarding the relationship between an individual's pathological burden and resulting cognitive impairment. To identify correlates of preserved cognitive functioning at highest age, the relationship between β-amyloid plaque load, presence of small vessel cerebrovascular disease (SVCD), iron-burden, and brain atrophy was investigated. Eighty cognitively unimpaired participants (44 oldest-old, aged 85-96 years; 36 younger-old, aged 55-80 years) were scanned by integrated positron emission tomography-magnetic resonance imaging for assessing beta regional amyloid plaque load (18F-flutemetamol), white matter hyperintensities as an indicator of SVCD (fluid-attenuated inversion recovery-magnetic resonance imaging), and iron load (quantitative susceptibility mapping). For the oldest-old group, lower cortical volume, increased β-amyloid plaque load, prevalence of SVCD, and lower cognitive performance in the normal range were found. However, compared to normal-old, cortical iron burden was lower in the oldest-old. Moreover, only in the oldest-old, entorhinal cortex volume positively correlated with β-amyloid plaque load. Our data thus indicate that the co-occurrence of aging-associated neuropathologies with reduced quantitative susceptibility mapping measures of cortical iron load constitutes a lower vulnerability to cognitive loss.

INTRODUCTION:Machine learning (ML) is a field in computer science that demonstrated to effectively integrate clinical and imaging data for the creation of prognostic scores. The current study investigated whether a ML score, incorporating only the 16 segment coronary tree information derived from coronary computed tomography angiography (CCTA), provides enhanced risk stratification compared with current CCTA based risk scores. METHODS:From the multi-center CONFIRM registry, patients were included with complete CCTA risk score information and ≥3 year follow-up for myocardial infarction and death (primary endpoint). Patients with prior coronary artery disease were excluded. Conventional CCTA risk scores (conventional CCTA approach, segment involvement score, duke prognostic index, segment stenosis score, and the Leaman risk score) and a score created using ML were compared for the area under the receiver operating characteristic curve (AUC). Only 16 segment based coronary stenosis (0%, 1-24%, 25-49%, 50-69%, 70-99% and 100%) and composition (calcified, mixed and non-calcified plaque) were provided to the ML model. A boosted ensemble algorithm (extreme gradient boosting; XGBoost) was used and the entire data was randomly split into a training set (80%) and testing set (20%). First, tuned hyperparameters were used to generate a trained model from the training data set (80% of data). Second, the performance of this trained model was independently tested on the unseen test set (20% of data). RESULTS:In total, 8844 patients (mean age 58.0 ± 11.5 years, 57.7% male) were included. During a mean follow-up time of 4.6 ± 1.5 years, 609 events occurred (6.9%). No CAD was observed in 48.7% (3.5% event), non-obstructive CAD in 31.8% (6.8% event), and obstructive CAD in 19.5% (15.6% event). Discrimination of events as expressed by AUC was significantly better for the ML based approach (0.771) vs the other scores (ranging from 0.685 to 0.701), P

Author(s): Cho, Yun-Kyeong; Nam, Chang-Wook; Koo, Bon-Kwon; Schulman-Marcus, Joshua; Hartaigh, Briain O; Gransar, Heidi; Lu, Yao; Achenbach, Stephan; Al-Mallah, Mouaz; Andreini, Daniele; Bax, Jeroen J; Budoff, Matthew J; Cademartiri, Filippo; Callister, Tracy Q; Chang, Hyuk-Jae; Chinnaiyan, Kavitha; Chow, Benjamin JW; Cury, Ricardo C; Delago, Augustin; Feuchtner, Gudrun; Hadamitzky, Martin; Hausleiter, Jorg; Kaufmann, Philipp A; Kim, Yong-Jin; Leipsic, Jonathon; Maffei, Erica; Marques, Hugo; Pontone, Gianluca; Raff, Gilbert L; Rubinshtein, Ronen; Shaw, Leslee J; Villines, Todd C; Berman, Daniel S; Jones, Erica C; Pena, Jessica M; Lin, Fay Y; Min, James K | Abstract: BackgroundThe extent to which the presence and extent of subclinical atherosclerosis by coronary computed tomography angiography influences a potential mortality benefit of statin is unknown. We evaluated the relationship between statin therapy, mortality, and subclinical atherosclerosis.MethodsIn the CONFIRM study, patients with normal or non-obstructive plaque (l50% diameter stenosis) for whom data on baseline statin use was available were included. Coronary artery calcium (CAC) was quantified using the Agatston score. The extent of non-obstructive coronary atherosclerosis was quantified using the segment involvement score (SIS). 8,016 patients were followed for a median of 2.5 years with analysis of all-cause mortality and major adverse cardiac events (MACE) including all-cause mortality, myocardial infarction, unstable angina, target vessel revascularization, and coronary artery disease-related hospitalization.Results1.2% of patients experienced all-cause mortality. Patients not on baseline statin therapy had a stepwise increased risk of all-cause mortality by CAC (relative to CAC = 0; CAC 1-99: hazard ratio [HR] 1.65, CAC 100-299: HR 2.19, and CAC≥300: HR 2.98) or SIS (relative to SIS = 0; SIS 1: HR 1.62, SIS 2-3: 2.48 and SIS≥4: 2.95). Conversely, in patients on baseline statin therapy, there was no significant increase in mortality risk with increasing CAC (p value for interaction = 0.049) or SIS (p value for interaction = 0.007). The incidence of MACE was 2.1%. Similar to the all-cause mortality, the risk of MACE was increased with CAC or SIS strata in patient not on baseline statin therapy. However, this relation was not observed in patient on baseline statin therapy.ConclusionIn individuals with non-obstructive coronary artery disease, increased risk of adverse events occurs with increasing CAC or SIS who are not on baseline statin therapy. Statin therapy is associated with a mitigation of risk of cardiac events in the presence of increasing atherosclerosis, with no particular threshold of disease burden.

The report of an imaging procedure is a critical component of an examination, being the final and often the only communication from the interpreting physician to the referring or treating physician. Very limited evidence and few recommendations or guidelines on reporting imaging studies are available; therefore, an European position statement on how to report nuclear cardiology might be useful. The current paper combines the limited existing evidence with expert consensus, previously published recommendations as well as current clinical practices. For all the applications discussed in this paper (myocardial perfusion, viability, innervation, and function as acquired by single photon emission computed tomography and positron emission tomography or hybrid imaging), headings cover laboratory and patient demographics, clinical indication, tracer administration and image acquisition, findings, and conclusion of the report. The statement also discusses recommended terminology in nuclear cardiology, image display, and preliminary reports. It is hoped that this statement may lead to more attention to create well-written and standardized nuclear cardiology reports and eventually lead to improved clinical outcome.

Aims We evaluated coronary artery disease (CAD) extent, severity, and major adverse cardiac events (MACEs) in never, past, and current smokers undergoing coronary CT angiography (CCTA). Methods and results We evaluated 9456 patients (57.1 +/- 12.3 years, 55.5% male) without known CAD (1588 current smokers; 2183 past smokers who quit >= 3 months before CCTA; and 5685 never smokers). By risk-adjusted Cox proportional-hazards models, we related smoking status to MACE (all-cause death or non-fatal myocardial infarction). We further performed 1: 1: 1 propensity matching for 1000 in each group evaluate event risk among individuals with similar age, gender, CAD risk factors, and symptom presentation. During a mean follow-up of 2.8 +/- 1.9 years, 297 MACE occurred. Compared with never smokers, current and past smokers had greater atherosclerotic burden including extent of plaque defined as segments with any plaque (2.1 +/- 2.8 vs. 2.6 +/- 3.2 vs. 3.1 +/- 3.3, P < 0.0001) and prevalence of obstructive CAD [1-vessel disease (VD): 10.6% vs. 14.9% vs. 15.2%, P < 0.001; 2-VD: 4.4% vs. 6.1% vs. 6.2%, P = 0.001; 3-VD: 3.1% vs. 5.2% vs. 4.3%, P < 0.001]. Compared with never smokers, current smokers experienced higher MACE risk [ hazard ratio (HR) 1.9, 95% confidence interval (CI) 1.4-2.6, P < 0.001], while past smokers did not (HR 1.2, 95% CI 0.8-1.6, P = 0.35). Among matched individuals, current smokers had higher MACE risk (HR 2.6, 95% CI 1.6-4.2, P < 0.001), while past smokers did not (HR 1.3, 95% CI 0.7-2.4, P = 0.39). Similar findings were observed for risk of all-cause death. Conclusion Among patients without known CAD undergoing CCTA, current and past smokers had increased burden of atherosclerosis compared with never smokers; however, risk of MACE was heightened only in current smokers.

OBJECTIVE: To develop a clinical cardiac risk algorithm for stable patients with suspected coronary artery disease based upon angina typicality and coronary artery disease risk factors. METHODS: Between 2004 and 2011, 14,004 adults with suspected coronary artery disease referred for cardiac imaging were followed: 1) 9093 patients for coronary computed tomography angiography (CCTA) followed for 2.0 years (CCTA-1); 2) 2132 patients for CCTA followed for 1.6 years (CCTA-2); and 3) 2779 patients for exercise myocardial perfusion scintigraphy (MPS) followed for 5.0 years. A best-fit model from CCTA-1 for prediction of death or myocardial infarction was developed, with integer values proportional to regression coefficients. Discrimination was assessed using C-statistic. The validated model was tested for estimation of the likelihood of obstructive coronary artery disease, defined as >= 50% stenosis, as compared with the method of Diamond and Forrester. Primary outcomes included all-cause mortality and nonfatal myocardial infarction. Secondary outcomes included prevalent angiographically obstructive coronary artery disease. RESULTS: In CCTA-1, best-fit model discriminated individuals at risk of death or myocardial infarction (C-statistic 0.76). The integer model ranged from 3 to 13, corresponding to 3-year death risk or myocardial infarction of 0.25% to 53.8%. When applied to CCTA-2 and MPS cohorts, the model demonstrated C-statistics of 0.71 and 0.77, respectively. Both best-fit (C = 0.76; 95% confidence interval [CI], 0.746-0.771) and integer models (C = 0.71; 95% CI, 0.693-0.719) performed better than Diamond and Forrester (C = 0.64; 95% CI, 0.628-0.659) for estimating obstructive coronary artery disease. CONCLUSIONS: For stable symptomatic patients with suspected coronary artery disease, we developed a history-based method for prediction of death and obstructive coronary artery disease. (C) 2015 Elsevier Inc. All rights reserved.

Objective: This study sought to determine the correlation between baseline cardiac medications and cardiovascular outcomes in patients with obstructive coronary artery disease (CAD) diagnosed by coronary computed tomographic angiography (CCTA). Methods: 1637 patients (mean age 64.8 +/- 10.2 years, 69.6% male) with obstructive CAD from the CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry were followed over the course of three years. Obstructive CAD was defined as a >= 50% stenosis in an epicardial vessel. Medications analyzed included statins, aspirin, beta-blockers, angiotensin converting enzyme (ACE) inhibitors, and angiotensin receptor blockers (ARBs). Using Cox proportional-hazards models, we calculated the hazard ratio (HR) with 95% confidence intervals (95% CIs) for incident major adverse cardiovascular events (MACE), defined as death, acute coronary syndrome, or myocardial infarction. Results: At the time of CCTA, 59%, 54%, 40%, and 46% of patients were using statins, aspirin, beta- blockers, and ACE inhibitors or ARBs, respectively. Statins were associated with a 43% (95% CI = 0.38-0.87, p = 0.008) lower adjusted risk of MACE. Following adjustment, aspirin, beta- blockers, ACE inhibitors and ARBs did not attenuate the risk of MACE. When restricted to patients with multivessel obstructive CAD, only statins were associated with lower risk of MACE. Conclusion: In patients with obstructive CAD by CCTA, the baseline use of statins was associated with improved clinical outcomes. Other cardiac medications-including aspirin, beta-blockers, ACE inhibitors, and ARBs-were not associated with reduced risk of MACE. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

HIV-positive persons have increased cardiovascular event rates but data on the prevalence of subclinical atherosclerosis compared with HIV-negative persons are not uniform. We assessed subclinical atherosclerosis utilizing coronary artery calcium (CAC) scoring and coronary computed tomography angiography (CCTA) in 428 HIV-positive participants of the Swiss HIV Cohort Study and 276 HIV-negative controls concurrently referred for clinically indicated CCTA.We assessed the association of HIV infection, cardiovascular risk profile, and HIV-related factors with subclinical atherosclerosis in univariable and multivariable analyses. HIV-positive participants (median duration of HIV infection, 15 years) were younger than HIV-negative participants (median age 52 vs. 56 years; P 0.01) but had similar median 10-year Framingham risk scores (9.0% vs. 9.7%; P = 0.40). The prevalence of CAC score0 (53% vs. 56.2%; P = 0.42) and median CAC scores (47 vs. 47; P = 0.80) were similar, as was the prevalence of any, non-calcified/mixed, and high-risk plaque. In multivariable adjusted analysis, HIV-positive participants had a lower prevalence of calcified plaque than HIV-negative participants [36.9% vs. 48.6%, P 0.01; adjusted odds ratio (aOR) 0.57; 95% confidence interval (CI) 0.40-0.82; P 0.01], lower coronary segment severity score (aOR 0.72; 95% CI 0.53-0.99; P = 0.04), and lower segment involvement score (aOR 0.71, 95% CI 0.52-0.97; P = 0.03). Advanced immunosuppression was associated with non-calcified/mixed plaque (aOR 1.97; 95% CI 1.09-3.56; P = 0.02).HIV-positive persons in Switzerland had a similar degree of non-calcified/mixed plaque and high-risk plaque, and may have less calcified coronary plaque, and lower coronary atherosclerosis involvement and severity scores than HIV-negative persons with similar Framingham risk scores.

BACKGROUND: Although randomized trials have provided evidence for invasive fractional flow reserve to guide revascularization, evidence for non-invasive imaging is less well established. The present study investigated whether hybrid coronary computed tomography (CCTA)/single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) can identify patients who benefit from early revascularization compared to medical therapy. METHODS: This retrospective study consists of 414 patients referred for evaluation of known or suspected coronary artery disease (CAD) with CCTA/SPECT hybrid imaging. CCTA categorized patients into no CAD, non-high-risk CAD and high-risk CAD. In patients with CAD (n = 329), a matched finding (n = 75) was defined as a reversible perfusion defect in a territory subtended by a coronary artery with CAD. All other combinations of pathologic findings were classified as unmatched (n = 254). Death, myocardial infarction, unstable angina requiring hospitalization, and late coronary revascularization were defined as major adverse cardiac events (MACE). Cox hazards models included covariates age, male gender, more than two risk factors, previous CABG, high-risk CAD and early revascularization. RESULTS: During median follow-up of 6.0 years, 112 patients experienced a MACE (27%). Early revascularization (n = 50) was independently associated with improved outcome among patients with a matched finding (p

Aims Single-source, dual-energy coronary computed tomography angiography (CCTA) with monochromatic image reconstruction allows significant noise reduction. The aim of the study was to evaluate the impact of monochromatic CCTA image reconstruction on coronary stent imaging, as the latter is known to be affected by artefacts from highly attenuating strut material resulting in artificial luminal narrowing. Methods and results Twenty-one patients with 62 stents underwent invasive coronary angiography and single-source, dual-energy CCTA after stent implantation. Standard polychromatic images as well as eight monochromatic series (50, 60, 70, 80, 90, 100, 120, and 140 keV) were reconstructed for each CCTA. Signal and noise were measured within the stent lumen and in the aortic root. Mean in-stent luminal diameter was assessed in all CCTA reconstructions and compared with quantitative invasive coronary angiography (QCA). Luminal attenuation was higher in the stent than in the aortic root throughout all monochromatic reconstructions ( P < 0.001). An increase in monochromatic energy was associated with a decrease in luminal attenuation values ( P < 0.001). The mean in-stent luminal diameter underestimation by monochromatic CCTA compared with QCA was 90% at low monochromatic energy (50 keV) and improved to 37% at high monochromatic (140 keV) reconstruction while stent diameter was underestimated by 39% with standard CCTA. Conclusion Monochromatic CCTA can be used reliably in patients with coronary stents. However, reconstructions with energies below 80 keV are not recommended as the blooming artefacts are most pronounced at such low energies, resulting in up to 90% stent diameter underestimation.

The potential risks associated with cardiovascular imaging (CVI) have recently been debated, partly triggered by the rapid increase in the use of imaging procedures and new imaging modalities such as cardiac computed tomography (CT).1,2 The discussion has mainly focused only on a single-risk aspect such as radiation.3 However, the various procedures have several risks: stressors, contrast agents, invasiveness, radiation, etc. Even more important, the test must be related to the benefit of performing or not performing the test with the risk and drawbacks associated with the disease remaining undetected. We aimed to create a balanced analysis of immediate, short- and long-term risks associated with CVI in relation to the natural course of coronary artery disease (CAD) and to therapeutic interventions. The imaging tests for CAD were selected, since many CVI tests are commonly used. We analysed: (i) the risk of major cardiac events (MCEs) for each component of imaging test; (ii) the upper limit for each risk, in order to avoid underestimation of a risk; (iii) composite risks calculated for selected common diagnostic tests for CAD; (iv) the risks compared with the risk of the disease itself, to assess the potential benefits of tests; and (v) comparison with risks in regular life activities and that associated with trivial long-term prophylactic interventions such as aspirin use. This analysis is based on the data available from the literature. Data for risks related to some of the procedures are quite limited, for some variable, and for some of limited quality. Still we sought to present risk estimations from all the procedures using reliable studies and databases available from an extensive search of the literature. The detailed information about risk assessments is shown in Supplementary material. ### Definitions In the literature, risks are described in many different ways, e.g. ‘fatal, major, …

As a consequence of improved technology, there is growing clinical interest in the use of multi-detector row computed tomography (MDCT) for non-invasive coronary angiography. Indeed, the accuracy of MDCT to detect or exclude coronary artery stenoses has been high in many published studies. This report of a Writing Group deployed by the Working Group Nuclear Cardiology and Cardiac CT (WG 5) of the European Society of Cardiology and the European Council of Nuclear Cardiology summarizes the present state of cardiac CT technology, as well as the currently available data concerning its accuracy and applicability in certain clinical situations. Besides coronary CT angiography, the use of CT for the assessment of cardiac morphology and function, evaluation of perfusion and viability, and analysis of heart valves is discussed. In addition, recommendations for clinical applications of cardiac CT imaging are given and limitations of the technique are described.

A 40-year-old woman with a long history of atypical chest pain and no cardiac risk factors was referred for cardiac work-up. Cardiac stress testing on a treadmill ergometer revealed T-wave inversion in leads V1–V3 and an intermittent left bundle branch block. The patient was subsequently referred to cardiac magnetic resonance …

Aims To prospectively investigate the diagnostic accuracy of dual-source computed tomography coronary angiography (CTCA) to diagnose coronary stenoses in relation to body mass index (BMI), Agatston score (AS), and heart rate (HR) as compared with catheter coronary angiography (CCA). Methods and results Hundred and fifty consecutive patients (47 female, mean age 62.9 ± 12.1 years) underwent dual-source CTCA without HR control. Patients were divided into subgroups depending on the median of their BMI (26.0 kg/m2), AS (194), and HR (66 b.p.m.). CCA was considered the standard of reference. Mean BMI was 26.5 ± 4.2 kg/m2 (range 18.3–39.1 kg/m2), mean AS was 309 ± 408 (range 0–4387), and HR was 68.5 ± 12.6 b.p.m. (range 35–102 b.p.m.). Diagnostic image quality was found in 98.1% of all segments (2020/2059). Considering not-evaluative segments at CTCA as false-positive, overall per-patient sensitivity, specificity, positive, and negative predictive value were 96.6%, 86.8%, 82.6%, and 97.5%, respectively. High HR did not deteriorate diagnostic accuracy of CTCA. High BMI and AS were associated with a decrease in per-patient specificity to 84.1% and 77.8%, respectively, while sensitivity and negative predictive value remained high. Conclusion Dual-source CTCA provides high diagnostic accuracy irrespective of the HR and serves as a modality to rule-out coronary artery stenoses even in patients with high BMI and AS.

Background— Patients with obstructive (≥50% stenosis) left main (LM) coronary artery disease (CAD) are at high risk for adverse events; prior studies have also documented worse outcomes among women than men with severe multivessel/LM CAD. However, the prognostic significance of nonobstructive (1%–49% stenosis) LM CAD, including sex-specific differences, has not been previously examined. Methods and Results— In the long-term CONFIRM (Coronary CT Angiography Evaluation For Clinical Outcomes: An International Multicenter) registry, patients underwent elective coronary computed tomographic angiography for suspected CAD and were followed for 5 years. After excluding those with obstructive LM CAD, 5166 patients were categorized as having normal LM or nonobstructive LM (18% of cohort). Cumulative 5-year incidence of death, myocardial infarction, or revascularization was higher among patients with nonobstructive LM than normal LM in both women and men: women (34.3% versus 15.4%; P P P =0.001). In multivariable Cox regression, the presence of nonobstructive LM plaque increased the risk for the composite outcome in women (adjusted hazard ratio, 1.48; P =0.005) but not in men (adjusted hazard ratio, 0.98, P =0.806). In subgroup analysis, women with nonobstructive LM CAD had a nearly 80% higher risk for events than men with nonobstructive LM CAD (adjusted hazard ratio, 1.78; P =0.017); sex-specific interactions were not observed across other patterns (eg, location or extent) of nonobstructive plaque. Conclusion— Nonobstructive LM CAD was frequently detected on coronary computed tomographic angiography and strongly associated with adverse events among women. Recognizing the sex-specific prognostic significance of nonobstructive LM plaque may augment risk stratification efforts.

Sensitive visualization of recurrent prostate cancer foci is a challenge in patients with early biochemical recurrence (EBR). The recently establishedWe retrospectively analyzed a cohort of 56 consecutive patients who underwent aOverall, in 44 of 56 patients (78.6%) PSMA-positive lesions were detected. In four of nine patients (44.4%) with a PSA 0.2 ng/mL, suspicious lesions were detected (two pelvic and one paraaortic lymph nodes, and two bone metastases). In eight of 11 patients (72.7%) with a PSA between 0.2 and 0.5 ng/mL, suspicious lesions were detected (two local recurrences, six lymph nodes, and one bone metastasis). Five out of 20 patients with a PSA 0.5 ng/mL had extrapelvic disease. In 12 of 15 patients (80.0%) with a PSA between 0.5 and 2.0 ng/mL, suspicious lesions were detected (four local recurrences, nine lymph nodes, and four bone metastases). In 20 of 21 patients (95.2%) with a PSA2.0 ng/mL, suspicious lesions were detected. The overall interreader agreement for cancer detection was excellent (κ = 0.796, CI 0.645-0.947).Our data show that

Background and aimsCoronary artery calcium (CAC) scoring is a predictor of future adverse clinical events, and a surrogate measure of overall coronary artery plaque burden. Coronary computed tomographic angiography (CCTA) is a contrast-enhanced method that allows for visualization of plaque as well as whether that plaque causes luminal narrowing. To date, the prognosis of individuals with CAC but without stenosis has not been reported. We explored the prevalence of CAC>0 and its prognostic utility for future mortality for patients without luminal narrowing by CCTA.MethodsFrom 17 sites in 9 countries, we identified patients without known coronary artery disease, who underwent CAC scoring and CCTA, and were followed for >3 years. CCTA was graded for % stenosis according to a modified American Heart Association 16-segment model. We calculated hazard ratios (HR) with 95% confidence intervals (95% CI) for incident mortality and compared risk of death for patients as a function of presence or absence of CAC and presence or absence of luminal narrowing by CCTA.ResultsAmong 6656 patients who underwent CCTA and CAC scoring, 399 patients (6.0%) had no coronary luminal narrowing but CAC>0. During a median follow-up of 5.1 years (IQR: 3.9-5.9 years), 456 deaths occurred. Compared to individuals without luminal narrowing or CAC, individuals without luminal narrowing but CAC>0 were older, more likely to be male and had higher rates of diabetes, hypertension, and dyslipidemia. Individuals without luminal narrowing but CAC experienced a 2-fold increased risk of mortality, with increasing risk of mortality with higher CAC score. Following adjustment, incident death persisted (HR, 1.8; 95% CI, 1.1-2.9, p=0.02) among patients without luminal narrowing but with CAC>0 compared with patients whose CACS=0. Individuals without luminal narrowing but CAC ≥100 had mortality risks similar to individuals with non-obstructive CAD (0&nbsp

Precise definition of the mitral valve plane (VP) during segmentation of the left ventricle for SPECT myocardial perfusion imaging (MPI) quantification often requires manual adjustment, which affects the quantification of perfusion. We developed a machine learning approach using support vector machines (SVM) for automatic VP placement. Methods: A total of 392 consecutive patients undergoing 99mTc-tetrofosmin stress (5 min; mean ± SD, 350 ± 54 MBq) and rest (5 min; 1,024 ± 153 MBq) fast SPECT MPI attenuation corrected (AC) by CT and same-day coronary CT angiography were studied; included in the 392 patients were 48 patients who underwent invasive coronary angiography and had no known coronary artery disease. The left ventricle was segmented with standard clinical software (quantitative perfusion SPECT) by 2 experts, adjusting the VP if needed. Two-class SVM models were computed from the expert placements with 10-fold cross validation to separate the patients used for training and those used for validation. SVM probability estimates were used to compute the best VP position. Automatic VP localizations on AC and non-AC images were compared with expert placement on coronary CT angiography. Stress and rest total perfusion deficits and detection of per-vessel obstructive stenosis by invasive coronary angiography were also compared. Results: Bland–Altman 95% confidence intervals (CIs) for VP localization by SVM and experts for AC stress images (bias, 1; 95% CI, −5 to 7 mm) and AC rest images (bias, 1; 95% CI, −7 to 10 mm) were narrower than interexpert 95% CIs for AC stress images (bias, 0; 95% CI, −8 to 8 mm) and AC rest images (bias, 0; 95% CI, −10 to 10 mm) (P < 0.01). Bland–Altman 95% CIs for VP localization by SVM and experts for non-AC stress images (bias, 1; 95% CI, −4 to 6 mm) and non-AC rest images (bias, 2; 95% CI, −7 to 10 mm) were similar to interexpert 95% CIs for non-AC stress images (bias, 0; 95% CI, −6 to 5 mm) and non-AC rest images (bias, −1; 95% CI, −9 to 7 mm) (P was not significant [NS]). For regional detection of obstructive stenosis, ischemic total perfusion deficit areas under the receiver operating characteristic curve for the 2 experts (AUC, 0.79 [95% CI, 0.7–0.87]; AUC, 0.81 [95% CI, 0.73–0.89]) and the SVM (0.82 [0.74–0.9]) for AC data were the same (P = NS) and were higher than those for the unadjusted VP (0.63 [0.53–0.73]) (P < 0.01). Similarly, for non-AC data, areas under the receiver operating characteristic curve for the experts (AUC, 0.77 [95% CI, 0.69–0.89]; AUC, 0.8 [95% CI, 0.72–0.88]) and the SVM (0.79 [0.71–0.87]) were the same (P = NS) and were higher than those for the unadjusted VP (0.65 [0.56–0.75]) (P < 0.01). Conclusion: Machine learning with SVM allows automatic and accurate VP localization, decreasing user dependence in SPECT MPI quantification.

AIMS: To identify the effect of early revascularization on 5-year survival in patients with CAD diagnosed by coronary-computed tomographic angiography (CCTA). METHODS AND RESULTS: We examined 5544 stable patients with suspected CAD undergoing CCTA who were followed a median of 5.5 years in a large international registry. Patients were categorized as having low-, intermediate-, or high-risk CAD based on CCTA findings. Two treatment groups were defined: early revascularization within 90 days of CCTA (n = 1171) and medical therapy (n = 4373). To account for the non-randomized referral to revascularization, we developed a propensity score by logistic regression. This score was incorporated into Cox proportional hazard models to calculate the effect of revascularization on all-cause mortality. Death occurred in 363 (6.6%) patients and was more frequent in medical therapy. In multivariable models, when compared with medical therapy, the mortality benefit of revascularization varied significantly over time and by CAD risk (P for interaction 0.04). In high-risk CAD, revascularization was significantly associated with lower mortality at 1 year (hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.11-0.47) and 5 years (HR 0.31, 95% CI 0.18-0.54). For intermediate-risk CAD, revascularization was associated with reduced mortality at 1 year (HR 0.45, 95% CI 0.22-0.93) but not 5 years (HR 0.63, 95% CI 0.33-1.20). For low-risk CAD, there was no survival benefit at either time point. CONCLUSIONS: Early revascularization was associated with reduced 1-year mortality in intermediate- and high-risk CAD detected by CCTA, but this association only persisted for 5-year mortality in high-risk CAD. info:eu-repo/semantics/publishedVersion

To evaluate the impact of a low-dose (LD) and an ultra-LD (ULD) contrast protocol for coronary CT angiography on qualitative and quantitative image parameters in a clinical setting.We scanned 120 consecutive patients with a 256-slice CT scanner applying a LD (60 patients, 35-55 ml) or ULD (60 patients, 25-45 ml) contrast protocol adapted to the body mass index. Visually assessed image quality and attenuation measured in each coronary segment were retrospectively compared in 20 consecutive patients scanned with a normal-dose (ND, 40-105 ml) contrast protocol.Visually assessed image quality did not differ significantly among protocols. By contrast, attenuation obtained from the ULD protocol (median contrast volume 35 ml) differed significantly from the LD (median 45 ml) and ND (median 70 ml) protocols in the coronary segments (316 ± 52 vs 363 ± 60 and 359 ± 52 HU, p 0.001). Attenuation did not differ significantly between the LD and ND protocol. The proportion of patients with inadequate coronary vessel attenuation was significantly higher (p 0.001) in the ULD protocol (37%) than in the ND (5%) and LD (10%) protocols but did not differ significantly between the ND and LD protocols.In a clinical setting, a LD contrast protocol with a median volume of 45 ml is feasible for the latest generation 256-slice coronary CT angiography as it yields attenuation comparable to a ND protocol. By contrast, the implementation of an ULD protocol remains challenging. Advances in knowledge: Although not perceived by the naked eye, an ULD contrast protocol in a clinical setting yields attenuation below a threshold for diagnostic image quality.

Diabetes mellitus (DM) is an important coronary artery disease (CAD) risk factor, however the concept of ‘DM as a CAD equivalent’ remains controversial. We aimed to explore the prognostic impact of DM and CAD in patients undergoing SPECT MPI. 20,309 patients (Age: 53±27, 57% male) with 4.5

Background: Coronary computed tomography angiography (CTA) is increasingly being used for evaluation of coronary artery disease (CAD). As a result of the widely reported potential of carcin...

Current scores that predict the presence of obstructive coronary artery disease (CAD) have moderate accuracy. We sought to develop a machine learning (ML) model, utilizing clinical factors and the coronary artery calcium score (CACS), to predict patients likely to have obstructive CAD on CCTA. The

Long term follow-up of coronary CT angiography (CCTA) is scarce. The aim of the present study was to assess the prognostic value of CCTA over a follow-up period of more than 6 years. 218 Patients were included undergoing 64-slice CCTA. Images were analysed with regard to the presence of nonobstructive (

AIMS: Inflammation is a key factor in the long-term outcome of acute coronary syndromes (ACS). The aim of the present study was to evaluate inflammatory markers in patients with ACS as predictors for major adverse cardiovascular events (MACE) and hard events. METHODS: This study included 1548 patients with ACS. C-reactive protein (CRP), white blood count (WBC), and their subtypes were analyzed during hospitalization. Receiver operator characteristic (ROC) and Kaplan-Meier survival curves were used to assess the predictive value and hard events (nonfatal myocardial infarction and cardiac death) and MACE (hard events, hospitalization for cardiac causes, late revascularization and stroke) were obtained during 30 days. RESULTS: ROC analysis of CRP and WBC to predict adverse events revealed cut-offs of 47.5 ng/l and 16.6 × 10/μl for MACE and 93.5 ng/l and 16.6 × 10/μl for hard events. The cumulative adverse event rates were significantly higher in patients with increased CRP (≥47.5 ng/l; 17 versus 4%, P

Objectives It remains still unclear whether the use of modern noninvasive diagnostic modalities for evaluation of coronary artery disease (computed tomography coronary angiography (CTCA), nuclear myocardial perfusion imaging (MPI)) were able to change the “diagnostic yield” of invasive coronary angiography (ICA). Methods The total number of ICA in the years 2000–2009 was related to the number of percutaneous interventions (PCIs) and we assessed whether there was a significant trend over time using time series analyses. We compared these data with the number of patients undergoing CTCA and nuclear MPI in the same time period. Results During the 10-year observational period, 23,397 ICA were performed. The proportion of purely diagnostic ICA (without PCI) remained stable over the whole study period (tau = −0.111, P = 0.721). A CTCA program was initiated in 2005 and 1,407 examinations were performed until 2009. Similarly, the number of nuclear MPI increased from 2,284 in the years 2000–2004 to 5,260 in the years 2005–2009 (P = 0.009). Conclusion Despite increasing availability, noninvasive testing modalities did not significantly alter the rate of purely diagnostic ICA, and still are underused as gatekeeper to ICA. Further effort is needed to optimize the use of noninvasive imaging modalities in the work-up process for coronary artery disease. (J Interven Cardiol 2014;27:50–57)

UNLABELLED The aim of this study was to explore the feasibility of attenuation correction (AC) of myocardial perfusion imaging (MPI) with a virtual unenhanced cardiac CT scan synthesized from contrast enhanced single source dual energy coronary CT angiography. METHODS Segmental myocardial percentage uptake values obtained with AC were analyzed by use of correlation analysis and Bland Altman limits of agreement (20 segment model) and clinical agreement was evaluated in 30 patients. RESULTS The 2 methods showed an excellent correlation for segmental myocardial percentage uptake at stress (r = 0.93; P < 0.001; low dose) and at rest (r = 0.90; P < 0.001; high dose) with narrow Bland Altman limits of agreement ( 6.8 to 7.8 and 7.8 to 7.4 respectively). The levels of clinical agreement of SPECT MPI corrected with standard versus virtual unenhanced CT AC were 99 per coronary territory and 97 per patient. CONCLUSION Our results suggest that AC of SPECT MPI with a virtual unenhanced CT scan synthesized from contrast enhanced coronary CT angiography is feasible and reliable.

Angiographic severity of coronary artery stenosis has historically been the primary guide to revascularization or medical management of coronary artery disease. However, physiologic severity defined by coronary pressure and/or flow has resurged into clinical prominence as a potential, fundamental change from anatomically to physiologically guided management. This review addresses clinical coronary physiology-pressure and flow-as clinical tools for treating patients. We clarify the basic concepts that hold true for whatever technology measures coronary physiology directly and reliably, here focusing on positron emission tomography and its interplay with intracoronary measurements.

Assessment of coronary artery calcification is increasingly used for cardiovascular risk stratification. We evaluated the reliability of calcium-scoring results using a novel iterative reconstruction algorithm (ASIR) on a high-definition 64-slice CT scanner, as such data is lacking.In 50 consecutive patients Agatston scores, calcium mass and volume score were assessed. Comparisons were performed between groups using filtered back projection (FBP) and 20-100% ASIR algorithms. Calcium score was measured in the coronary arteries, signal and noise were measured in the aortic root and left ventricle. In comparison with FBP, use of 20%, 40%, 60%, 80%, and 100% ASIR resulted in reduced image noise between groups (7.7%, 18.8%, 27.9%, 39.86%, and 48.56%, respectively; p0.001) without difference in signal (p=0.60). With ASIR algorithms Agatston coronary calcium scoring significantly decreased compared with FBP algorithms (837.3 ± 130.3; 802.2 ± 124.9, 771.5 ± 120.7; 744.7 ± 116.8, 724.5 ± 114.2, and 709.2 ± 112.3 for 0%, 20%, 40%, 60%, 80%, and 100% ASIR, respectively, p0.001). Volumetric score decreased in a similar manner (p0.001) while calcium mass remained unchanged. Mean effective radiation dose was 0.81 ± 0.08 mSv.ASIR results in image noise reduction. However, ASIR image reconstruction techniques for HDCT scans decrease Agatston coronary calcium scores. Thus, one needs to be aware of significant changes of the scoring results caused by different reconstruction methods.

The aim of the present study was to assess the long-term predictive value of myocardial perfusion imaging (MPI) with (13)N-ammonia positron emission tomography (PET) in patients with suspected myocardial perfusion abnormality. At present, outcome data on the predictive value of MPI in (13)N-ammonia PET exist only for rather small patient populations.Cardiac perfusion was assessed in 943 consecutive patients using (13)N-ammonia PET, and follow-up was obtained in 698 (74%). 77 patients who underwent early revascularization (60 days) were excluded and 621 patients were assigned to normal versus abnormal perfusion for outcome analysis. Hard events (cardiac death and non-fatal myocardial infarction) and major adverse cardiac events (MACE; hard events, hospitalization for cardiac reasons and late revascularization) were investigated using the Kaplan-Meier method. Independent predictors for various cardiac events were identified using Cox proportional hazard regression analysis.During follow-up (5.7 ± 2.5 years), 275 patients had at least 1 cardiac event, including 102 cardiac deaths and 33 non-fatal myocardial infarction. Abnormal perfusion (n=469) was associated with a higher incidence of MACE (P0.001) and hard events (P0.001) throughout the 10-year follow-up period.Cardiac perfusion findings in (13)N-ammonia PET are strong predictors of long-term outcome.

Objectives The aim of this study was to analyze the predictive value of coronary computed tomography angiography (CCTA) and to model and validate an optimized score for prognosis of 2-year survival on the basis of a patient population with suspected coronary artery disease (CAD). Background Coronary computed tomography angiography carries important prognostic information in addition to the detection of obstructive CAD. But it is still unclear how the results of CCTA should be interpreted in the context of clinical risk predictors. Methods The analysis is based on a test sample of 17,793 patients and a validation sample of 2,506 patients, all with suspected CAD, from the international CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry. On the basis of CCTA data and clinical risk scores, an optimized score was modeled. The endpoint was all-cause mortality. Results During a median follow-up of 2.3 years, 347 patients died. The best CCTA parameter for prediction of mortality was the number of proximal segments with mixed or calcified plaques (C-index 0.64, p 50% (C-index 0.56, p = 0.002). In an optimized score including both parameters, CCTA significantly improved overall risk prediction beyond National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III) score as best clinical score. According to this score, a proximal segment with either a mixed or calcified plaque or a stenosis >50% is equivalent to a 5-year increase in age or the risk of smoking. Conclusions In CCTA, both plaque burden and stenosis, particularly in proximal segments, carry incremental prognostic value. A prognostic score on the basis of this data can improve risk prediction beyond clinical risk scores.

Aims Magnetic resonance (MR) imaging is widely used for diagnostic imaging in medicine as it is considered a safe alternative to ionizing radiation-based techniques. Recent reports on potential genotoxic effects of strong and fast switching electromagnetic gradients such as used in cardiac MR (CMR) have raised safety concerns. The aim of this study was to analyse DNA double-strand breaks (DSBs) in human blood lymphocytes before and after CMR examination. Methods and results In 20 prospectively enrolled patients, peripheral venous blood was drawn before and after 1.5 T CMR scanning. After density gradient cell separation of blood samples, DNA DSBs in lymphocytes were quantified using immunofluorescence microscopy and flow cytometric analysis. Wilcoxon signed-rank testing was used for statistical analysis. Immunofluorescence microscopic and flow cytometric analysis revealed a significant increase in median numbers of DNA DSBs in lymphocytes induced by routine 1.5 T CMR examination. Conclusion The present findings indicate that CMR should be used with caution and that similar restrictions may apply as for X-ray-based and nuclear imaging techniques in order to avoid unnecessary damage of DNA integrity with potential carcinogenic effect.