Usefulness of coronary computed tomographic angiography to assess suitability for revascularization in patients with significant coronary artery disease and angina pectoris

Abstract

Coronary computed tomographic angiography (CTA) accurately excludes the presence of coronary stenoses in selected patient populations. However, it remains unclear whether coronary CTA has the potential to replace invasive coronary angiography as a tool to assess a patient's suitability for revascularization as determined by the characterization of lesion morphology in patients with significant coronary artery disease. Coronary CTA (64-slice computed tomography) was performed before invasive coronary angiography in 29 patients. We evaluated the accuracy of CTA for the detection of complex lesion morphology, including the presence of severe calcium, total occlusions, and ostial or bifurcation location, and compared the results with those of invasive angiography. On CTA, 10 of 69 lesions (15%) were not evaluable for any feature of complex lesion morphology. Of the evaluable lesions, CTA detected >or=1 feature of complexity in 58% of lesions, corresponding to a sensitivity of 88% (23 of 26) and a specificity of 83% (24 of 29). For those single features, the sensitivity of CTA was 100% for the presence of severe calcium, 93% for total occlusions, and 60% and 80% for the detection of ostial and bifurcation lesions, respectively. The specificity was high for total occlusions (97%), ostial lesions (97%), and bifurcations (100%). It was moderate (85%) for severe calcium. Severe calcium precluded the evaluation of other features of complex lesion morphology in 6 lesions (11%). In conclusion, invasive selective coronary angiography remains the cornerstone to assess a patient's suitability for revascularization given the high proportion of unevaluable segments and segments with severe calcium that precluded adequate revascularization planning on CTA.