To compare the accuracy of combined 64-slice computed tomography angiography (CTA) and stress nuclear myocardial perfusion imaging (MPI) in the noninvasive detection of coronary artery disease (CAD) with that of 64-slice CTA alone.

One hundred thirty symptomatic patients with suspected CAD underwent both 64-slice CTA and stress thallium-201 MPI before invasive coronary angiography (ICA). Coronary lesions with ≥50% luminal narrowing were considered as significant stenoses on CTA and ICA. Of 390 arteries in 130 patients, 54 (14%) were nonevaluable by CTA due to severe calcifications, motion artifacts, and/or poor opacification. All nonevaluable arteries were considered positive. The sensitivity, specificity, PPV and NPV were 95%, 80%, 69%, and 97%, respectively, for CTA alone and 94%, 92%, 85%, and 97%, respectively, for CTA with stress nuclear MPI for all nonevaluable arteries on CTA. Per-patient analysis showed significant increase in specificity and PPV. The majority (75%, 9/12) of nonevaluable severely calcified vessels in the left anterior descending artery were positive on stress nuclear MPI, whereas the majority (89%, 8/9) of nonevaluable vessels with motion artifacts in the right coronary artery were negative.

Combined CTA and stress nuclear MPI provide improved diagnostic accuracy for the noninvasive detection of CAD.