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Publications (2)20.26 Total impact

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    ABSTRACT: BACKGROUND: Although numerous trials have demonstrated the diagnostic accuracy of coronary artery calcium (CAC) scanning for prediction of obstructive disease, virtually all studies have been performed using Electron Beam CT (EBCT). We evaluated the diagnostic accuracy of CAC by 64-row CT to detect obstructive coronary stenosis compared to quantitative coronary angiography (QCA) in the ACCURACY multicenter trial. METHODS: 16 sites prospectively enrolled 230 patients (pts) [59.5% males, 57yrs] with chest pain referred for invasive coronary angiography (ICA). Pts underwent CAC scan and CT angiography prior to ICA. Total CAC scores were correlated with angiographically documented stenoses using common cutpoints of CAC >0, >100 and >400. Significant obstructive disease was defined as >50% luminal stenosis by QCA. RESULTS: The per-patient accuracy of CAC by 64-row CT compared to QCA demonstrates a high sensitivity and low specificity for the presence of obstructive disease (>50% stenosis on QCA). With CAC >0, >100 and >400, the sensitivities to predict stenosis were 98%, 88%, and 60%, whereas the specificities were 42%, 71%, and 88%, respectively. CONCLUSIONS: Most previous CAC studies have focused on the fact that significant calcium places patients into a higher risk group in terms of future events, and should lead to more aggressive treatment with preventative therapies. This prospective multicenter results comparing 64-row CAC to QCA demonstrate that CAC using 64-row CT scanner, similar to previously published reports using EBCT, is highly sensitive and moderately specific test to predict significant coronary artery stenosis. The presence of abnormal levels of calcium may place patients into a higher risk group in terms of future events, and lead to more aggressive treatment with preventative therapies. However, the detection of calcium does not always help with a clinical diagnosis particularly in the presence of diffuse moderate coronary atheroma. Whether this information is complementary to CTA data remains to be validated.
    International journal of cardiology 12/2011; · 6.18 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate the diagnostic accuracy of electrocardiographically gated 64-multidetector row coronary computed tomographic angiography (CCTA) in individuals without known coronary artery disease (CAD). CCTA is a promising method for detection and exclusion of obstructive coronary artery stenosis. To date, no prospective multicenter trial has evaluated the diagnostic accuracy of 64-multidetector row CCTA in populations with intermediate prevalence of CAD. We prospectively evaluated subjects with chest pain at 16 sites who were clinically referred for invasive coronary angiography (ICA). CCTAs were scored by consensus of 3 independent blinded readers. The ICAs were evaluated for coronary stenosis based on quantitative coronary angiography (QCA). No subjects were excluded for baseline coronary artery calcium score or body mass index. A total of 230 subjects underwent both CCTA and ICA (59.1% male; mean age: 57 +/- 10 years). On a patient-based model, the sensitivity, specificity, and positive and negative predictive values to detect > or =50% or > or =70% stenosis were 95%, 83%, 64%, and 99%, respectively, and 94%, 83%, 48%, 99%, respectively. No differences in sensitivity and specificity were noted for nonobese compared with obese subjects or for heart rates < or =65 beats/min compared with >65 beats/min, whereas calcium scores >400 reduced specificity significantly. In this prospective multicenter trial of chest pain patients without known CAD, 64-multidetector row CCTA possesses high diagnostic accuracy for detection of obstructive coronary stenosis at both thresholds of 50% and 70% stenosis. Importantly, the 99% negative predictive value at the patient and vessel level establishes CCTA as an effective noninvasive alternative to ICA to rule out obstructive coronary artery stenosis. (A Study of Computed Tomography [CT] for Evaluation of Coronary Artery Blockages in Typical or Atypical Chest Pain; NCT00348569).
    Journal of the American College of Cardiology 12/2008; 52(21):1724-32. · 14.09 Impact Factor