Relation Between Framingham Risk Categories and the Presence of Functionally Relevant Coronary Lesions as Determined on Multislice Computed Tomography and Stress Testing

Noninvasive assessment of subclinical atherosclerosis by multislice computed tomographic (MSCT) coronary angiography and demonstration of significant, flow-limiting coronary artery disease (CAD) by stress testing may improve patients' risk stratification. However, data relating the complementary information provided by these noninvasive techniques to traditional risk assessment are scarce. In 255 subjects (45% women, mean age 54 ± 12 years) without known CAD, 64-slice MSCT coronary angiography and stress testing (exercise electrocardiographic test or myocardial perfusion imaging) were performed. Framingham risk score (FRS) was calculated from baseline characteristics (50% low, 22% intermediate, 28% high). Angiograms showing atherosclerosis were classified as obstructive (≥50% luminal narrowing) CAD or not. Stress tests were classified as normal or abnormal. Multislice computed tomogram identified 155 patients (61%) with CAD, of whom 78 (31%) showed obstructive CAD. A positive stress test result was observed in 36 patients (46%) with obstructive CAD. In line with increasing FRS categories, a significant increase in the prevalence of functionally relevant obstructive CAD was observed (6% low vs 45% intermediate vs 63% high, p <0.001). In conclusion, a strong positive relation exists between FRS and prevalence of functionally relevant obstructive CAD. Selective use of MSCT coronary angiography and stress testing may refine the traditional risk assessment of CAD events, especially in patients deemed at intermediate and high risk.