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Objective: To examine the utility of repeated computed tomography (CT) coronary artery calcium (CAC) testing, we assessed risks of detectable CAC and its cardiovascular consequences in individuals with and without type 2 diabetes ages 45-85 years.Research Design and Methods: We included 5,836 individuals (618 with type 2 diabetes, 2,972 without baseline CAC) from the Multi-Ethnic Study of Atherosclerosis. With logistic and Cox regression we evaluated the impact of type 2 diabetes, diabetes treatment duration, and other predictors on prevalent and incident CAC. We used time-dependent Cox modeling of follow-up data (median 15.9 years) for two repeat CT exams and cardiovascular events to assess the association of CAC at follow-up CT with cardiovascular events.Results: For 45 year olds with type 2 diabetes, the likelihood of CAC at baseline was 23% vs. 17% for those without. Median age at incident CAC was 52.2 vs. 62.3 years for those with and without diabetes, respectively. Each 5 years of diabetes treatment increased the odds and hazard rate of CAC by 19% (95% CI 8-33) and 22% (95% CI 6-41). Male sex, White ethnicity/race, hypertension, hypercholesterolemia, obesity, and low serum creatinine also increased CAC. CAC at follow-up CT independently increased coronary heart disease rates.Conclusions: We estimated cumulative CAC incidence to age 85 years. Patients with type 2 diabetes develop CAC at a younger age than those without diabetes. Because incident CAC is associated with increased coronary heart disease risk, the value of periodic CAC-based risk assessment in type 2 diabetes should be evaluated. [ABSTRACT FROM AUTHOR]

Aims The severity of coronary artery narrowing is a poor predictor of functional significance, in particular in intermediate coronary lesions (30–70% diameter narrowing). The aim of this work was to compare the performance of a quantitative hyperaemic myocardial blood flow (MBF) index derived from adenosine dynamic computed tomography perfusion (CTP) imaging with that of visual CT coronary angiography (CTCA) and semi-automatic quantitative CT (QCT) in the detection of functionally significant coronary lesions in patients with stable chest pain. Methods and results CTCA and CTP were performed in 80 patients (210 analysable coronary vessels) referred to invasive coronary angiography (ICA). The MBF index (mL/100 mL/min) was computed using a model-based parametric deconvolution method. The diagnostic performance of the MBF index in detecting functionally significant coronary lesions was compared with visual CTCA and QCT. Coronary lesions with invasive fractional flow reserve of ≤0.75 were defined as functionally significant. The optimal cut-off value of the MBF index to detect functionally significant coronary lesions was 78 mL/100 mL/min. On a vessel-territory level, the MBF index had a larger area under the curve (0.95; 95% confidence interval [95% CI]: 0.92–0.98) compared with visual CTCA (0.85; 95% CI: 0.79–0.91) and QCT (0.89; 95% CI: 0.84–0.93) (both P-values <0.001). In the analysis restricted to intermediate coronary lesions, the specificity of visual CTCA (69%) and QCT (77%) could be improved by the subsequent use of the MBF index (89%). Conclusion In this proof-of-principle study, the MBF index performed better than visual CTCA and QCT in the identification of functionally significant coronary lesions. The MBF index had additional value beyond CTCA anatomy in intermediate coronary lesions. This may have a potential to support patient management. [ABSTRACT FROM PUBLISHER]

Background: Risk scores for prediction of coronaiy heart disease (CHD) in older adults are needed. Objective: To develop a sex-specific CHD risk prediction model for older adults that accounts for competing risks for death. Design: 2 observational cohort studies, using data from 4946 par-ticipants in the Cardiovascular Health Study (CHS) and 4303 par-ticipants in the Rotterdam Study (RS). Setting: Community settings in the United States (CHS) and Rot-terdam, the Netherlands (RS). Participants: Persons aged 65 years or older who were free of cardiovascular disease. Measurements: A composite of nonfatal myocardial infarction and coronary death. Results: During a median follow-up of 16.5 and 14.9 years, 1166 CHS and 698 RS participants had CHD events, respectively. Deaths from noncoronary causes largely exceeded the number of CHD events, complicating accurate CHD risk predictions. The prediction model had moderate ability to discriminate between events and nonevents (c-statistic, 0.63 in both U.S. and European men and 0.67 and 0.68 in U.S. and European women). The model was well-calibrated; predicted risks were in good agreement with observed risks. Compared with the Framingham point scores, the prediction model classified elderly U.S. persons into higher risk categories but elderly European persons into lower risk categories. Differences in classification accuracy were not consistent and de-pended on cohort and sex. Adding newer cardiovascular risk mark-ers to the model did not substantially improve performance. Limitation: The model may be less applicable in nonwhite popu-lations, and the comparison Framingham model was not designed for adults older than 79 years. Conclusion: A CHD risk prediction model that accounts for deaths from noncoronary causes among older adults provided well-calibrated risk estimates but was not substantially more accurate than Framingham point scores. Moreover, adding newer risk mark-ers did not improve accuracy. These findings emphasize the diffi-culties of predicting CHD risk in elderly persons and the need to improve these predictions. Primary Funding Source: National Heart, Lung, and Blood Insti-tute; National Institute of Neurological Disorders and Stroke; The Netherlands Organisation for Scientific Research; and the Nether-lands Organisation for Health Research and Development [ABSTRACT FROM AUTHOR]

Background: The National Cholesterol Education Program recommends assessing 10-year risk of coronary heart disease (CHD) in individuals free of established CHD with the Framingham Point Scores (FPS). Individuals with a risk >20% are classified as high risk and are candidates for preventive intervention. We aimed to validate the FPS in a European population of elderly subjects. Methods: Subjects free of established CHD at baseline were selected from the Rotterdam study, a population-based cohort of subjects 55 years or older in the Netherlands. We studied calibration, discrimination (c-index), and the accuracy of high-risk classifications. Events consisted of fatal CHD and nonfatal myocardial infarction. Results: Among 6795 subjects, 463 died because of CHD and 336 had nonfatal myocardial infarction. Predicted 10-year risk of CHD was on average well calibrated for women (9.9% observed vs 10.1% predicted) but showed substantial overestimation in men (14.3% observed vs 19.8% predicted), particularly with increasing age. This resulted in substantial number of false-positive classifications (specificity 70%) in men. In women, discrimination of the FPS was better than that in men (c-index 0.73 vs 0.63, respectively). However, because of the low baseline risk of CHD and limited discriminatory power, only 33% of all CHD events occurred in women classified as high risk. Conclusions: The FPS need recalibration for elderly men with better incorporation of the effect of age. In elderly women, FPS perform reasonably well. However, maintaining the rational of the high-risk threshold requires better performing models for a population with low incidence of CHD. [Copyright &y& Elsevier]

Abstract: Background: To evaluate the performance of Framingham predictions of cardiovascular disease (CVD) risk corrected for the competing risk of non-CVD death, in an independent European cohort of older individuals and subsequently extend the predictions by disentangling CVD into coronary heart disease (CHD) and stroke separately. Methods: We used the Rotterdam Study data, a prospective cohort study of individuals aged 55years and older (N =6004), to validate the Framingham predictions of CVD, defined as first occurrence of myocardial infarction, coronary death or stroke during 15years of follow-up, corrected for the competing risk of non-CVD death. We subsequently estimated the risks of CHD and stroke separately, and used the sum as a predictor for the total CVD risk. Calibration plots and c-statistics were used to evaluate the performance of the models. Results: Performance of the Framingham predictions was good in the low- to intermediate risk (≤30%, 15-year CVD risk) (17.5% observed vs. 16.6% expected) but poorer in the higher risk (>30%) categories (36.3% observed vs. 44.1% expected). The c-statistic increased from 0.66 to 0.69 after refitting. Separately estimating CHD and stroke revealed considerable heterogeneity with regard to the contribution of CHD and stroke to total CVD risk. Conclusions: Framingham CVD risk predictions perform well in the low- to intermediate risk categories in the Rotterdam Study. Disentangling CVD into CHD and stroke separately provides additional information about the individual contribution of CHD and stroke to total individual CVD risk. [Copyright &y& Elsevier]

Abstract: Background: To determine the comparative effectiveness and costs of a CT-strategy and a stress-electrocardiography-based strategy (standard-of-care; SOC-strategy) for diagnosing coronary artery disease (CAD). Methods: A decision analysis was performed based on a well-documented prospective cohort of 471 outpatients with stable chest pain with follow-up combined with best-available evidence from the literature. Outcomes were correct classification of patients as CAD− (no obstructive CAD), CAD+ (obstructive CAD without revascularization) and indication for Revascularization (using a combination reference standard), diagnostic costs, lifetime health care costs, and quality-adjusted life years (QALY). Parameter uncertainty was analyzed using probabilistic sensitivity analysis. Results: For men (and women), diagnostic cost savings were €245 (€252) for the CT-strategy as compared to the SOC-strategy. The CT-strategy classified 82% (88%) of simulated men (women) in the appropriate disease category, whereas 83% (85%) were correctly classified by the SOC-strategy. The long-term cost-effectiveness analysis showed that the SOC-strategy was dominated by the CT-strategy, which was less expensive (−€229 in men, −€444 in women) and more effective (+0.002 QALY in men, +0.005 in women). The CT-strategy was cost-saving (−€231) but also less effective compared to SOC (−0.003 QALY) in men with a pre-test probability of ≥70%. The CT-strategy was cost-effective in 100% of simulations, except for men with a pre-test probability ≥70% in which case it was 59%. Conclusions: The results suggest that a CT-based strategy is less expensive and equally effective compared to SOC in all women and in men with a pre-test probability <70%. [Copyright &y& Elsevier]

Objectives: The purpose of this study was to critically appraise guidelines on imaging of asymptomatic coronary artery disease (CAD). Background: Various imaging tests exist to detect CAD in asymptomatic persons. Because randomized controlled trials are lacking, guidelines that address the use of CAD imaging tests may disagree. Methods: Guidelines in English published between January 1, 2003, and February 26, 2010, were retrieved using MEDLINE, Cumulative Index to Nursing and Allied Health Literature, the National Guideline Clearinghouse, the National Library for Health, the Canadian Medication Association Infobase, and the Guidelines International Network International Guideline Library. Guidelines developed by national and international medical societies from Western countries, containing recommendations on imaging of asymptomatic CAD were included. Rigor of development was scored by 2 independent reviewers using the Appraisal of Guidelines Research and Evaluation (AGREE) instrument. One reviewer performed full extraction of recommendations, which was checked by a second reviewer. Results: Of 2,415 titles identified, 14 guidelines met our inclusion criteria. Eleven of 14 guidelines reported relationship with industry. The AGREE scores varied across guidelines from 21% to 93%. Two guidelines considered cost effectiveness. Eight guidelines recommended against or found insufficient evidence for testing of asymptomatic CAD. The other 6 guidelines recommended imaging patients at intermediate or high CAD risk based on the Framingham risk score, and 5 considered computed tomography calcium scoring useful for this purpose. Conclusions: Guidelines on risk assessment by imaging of asymptomatic CAD contain conflicting recommendations. More research, including randomized controlled trials, evaluating the impact of imaging on clinical outcomes and costs is needed. [ABSTRACT FROM AUTHOR]