Predictive Value of 16-Slice Multidetector Spiral Computed Tomography to Detect Significant Obstructive Coronary Artery Disease in Patients at High Risk for Coronary Artery Disease Patient- Versus Segment-Based Analysis

Background—In this study, we investigated the diagnostic value and limitations of multidetector computed tomography (MDCT)–based noninvasive detection of significant obstructive coronary artery disease (CAD) in a consecutive high-risk patient population with inclusion of all coronary segments. Methods and Results—In a prospective, blinded, standard cross-sectional technology assessment, a cohort of 33 consecutive patients with a positive stress test result underwent 16-slice MDCT and selective coronary angiography for the detection of significant obstructive CAD. We assessed the diagnostic accuracy of MDCT in a segment-based and a patient-based model and determined the impact of stenosis location and the presence of calcification on diagnostic accuracy in both models. Analysis of all 530 coronary segments demonstrated moderate sensitivity (63%) and excellent specificity (96%) with a moderate positive predictive value of 64 % and an excellent negative predictive value (NPV) of 96 % for the detection of significant coronary stenoses. Assessment restricted to either proximal coronary segments or segments with excellent image quality (83 % of all segments) led to an increase in sensitivity (70 % and 82%, respectively), and high specificities were maintained (94 % and 93%, respectively). In a patient-based model, the NPV of MDCT for significant CAD was limited to 75%. Coronary calcification was the major cause of false-positive findings (94%). Conclusions—For all coronary segments included, 16-slice MDCT has moderate diagnostic value for the detection o