Head-to-head comparison between bicycle exercise testing and coronary calcium score and coronary stenoses on multislice computed tomography.

ABSTRACT

OBJECTIVE: To perform a head-to-head comparison between signs of ischemia during bicycle exercise testing and coronary atherosclerosis on multislice computed tomography (MSCT) in patients with suspected coronary artery disease (CAD). METHODS: Two hundred and one patients underwent exercise testing, followed by 64-slice MSCT. A subgroup of 63 (31%) patients also underwent conventional coronary angiography. The exercise test was positive or negative based on electrocardiographic signs of ischemia. On MSCT, total calcium score was obtained. Based on MSCT angiography, the patients were classified as having normal MSCT or coronary atherosclerosis [with nonobstructive and obstructive CAD (>/=50% luminal narrowing) present]. RESULTS: In 178 patients with interpretable examinations, the exercise test was positive in 36 (20%) and negative in 142 (80%) patients. Calcium score was identical in patients with a positive [median (interquartile range) 11 (0-343)] and a negative exercise test [18 (0-335), P=NS]. The prevalence of nonobstructive CAD was the same in two patients groups [13 (36%) patients with a positive vs. 54 (38%) patients with a negative exercise test, P=NS]. Although obstructive CAD was observed in 15 (42%) patients having a positive exercise test, obstructive lesions were also present in 38 (27%) patients without ischemia on exercise testing. The findings were confirmed by conventional coronary angiography. CONCLUSION: No correlation was observed between ischemia on exercise testing and both calcium scoring and nonobstructive CAD on MSCT. A large proportion of obstructive lesions on MSCT were not observed on exercise testing. Potentially, MSCT may provide additional information on CAD.