Abstract 5803: Optimal Threshold for Multi Detector Computer Tomography to Detect Physiologically Significant Stenosis in Patients with Ischemic Heart Disease
PURPOSE: Sixty-four multi detector computed tomography angiography (64-MDCT) has emerged as a rapidly developing method for the noninvasive detection of coronary artery disease with high negative predictive value and relatively low positive predictive value, especially in patients with intermediate-severity coronary artery disease (ISCAD). There are, however, few studies regarding with optimal threshold for detection of physiologically significant stenosis in 64-MDCT. The purpose of this study was to investigate the optimal threshold for 64-MDCT to detect physiologically significant stenosis using fractional flow reserve of the myocardium (FFRmyo) in patients with ISCAD.
METHODS: We enrolled single lesions detected by 64-MDCT of 64 ISCAD patients (age, 68.3 +/− 10.2 years; 78% male). FFRmyo </= 0.75 measured by a 0.014-inch pressure wire was used as the gold standard for presence of physiologically significant stenosis. The area stenosis (%AS) in 64-MDCT were compared with the results of FFRmyo and percent diameter stenosis (%DS) in quantitative coronary angiography (QCA) during elective coronary angiography. Using receiver operating characteristic (ROC) analysis, the optimum threshold for percent area stenosis (%AS) in 64-MDCT was determined in the prediction of FFRmyo </= 0.75.
RESULTS: There was an inverse correlation between %AS in 64-MDCT and FFRmyo (65 +/− 20 % and 0.71 +/− 0.16, respectively; r = −0.67; p < 0.01). Furthermore, there was a positive correlation between %AS in 64-MDCT and %DS in QCA (65 +/− 20 % and 63 +/− 19 %, respectively; r = 0.69; p < 0.01). Using a cutoff of 62 %AS in 64-MDCT, ROC curve analysis shows 79 % sensitivity, 85 % specificity, 82% positive predictive value, 83% negative predictive value and 83% accuracy for detecting physiologically significant stenosis.
CONCLUSION: >62 %AS in 64-MDCT could predict the physiologically significant coronary stenosis in patients with ISCAD. Applying an alternative threshold to detect physiologically significant stenosis might contribute to improve the diagnostic accuracy for 64-MDCT in patients with ISCAD.