Purpose: To evaluate the prevalence of significant coronary artery disease (CAD) and nondiagnostic studies in patients referred for clinically indicated coronary angiography performed by 128 multidetector computed tomography (MDCT).
Methods: We examined patients referred for coronary computed tomography (CT) angiography for the presence of CAD. The analysis included 438 studies classified as normal, with nonsignificant CAD, with significant CAD, or nondiagnostic.
Results: Of the 438 cases evaluated, 121 (27.6%) cases were reported as normal, 184 (42%) were classified as nonsignificant CAD, 92 (21%) as significant CAD, and 41 (9.3%) were inconclusive. Therefore, 69.7% of the study population most probably did not require conventional coronary angiography.
Conclusion: Among patients referred for computed tomography angiography (CTA) for appropriate indications, 69.6% had either normal coronary arteries or nonobstructive disease. Given the high negative predictive value of coronary CTA, these patients most likely would not require invasive coronary angiography. Selective cardiac CTA may substantially decrease unnecessary diagnostic cardiac catheterizations.