Abstract 20015: Value of Quantitative Atherosclerotic Plaque Assessment Using CCTA to Predict Lesion-specific Ischemia, Data from 407 Coronary Lesions

Introduction: While coronary computed tomographic angiography (CCTA) demonstrates high diagnostic performance for identification and exclusion of high-grade anatomic stenosis, it is unable to effectively discriminate coronary lesions that causes ischemia. Hypothesis: To study whether quantitative assessment of CCTA offer incremental information for discrimination of lesion ischemia beyond stenosis measures. Methods: 252 consecutive patients with suspected or known coronary artery disease (CAD) from 17 centers in 5 countries were enrolled (mean age 63±9 years, 71% male). Patients underwent CCTA and invasive coronary angiography (ICA), with 407 coronary lesions interrogated by invasive fractional flow reserve (FFR) at the time of maximum hyperemia. For these coronary lesions, we evaluated % diameter stenosis (%DS), % area stenosis (%AS), minimal luminal diameter (MLD, mm), minimal luminal area (MLA, mm 2 ), and plaque burden at MLA by CCTA. Plaque burden (PB, %) was defined as (vessel area–lumen area)/vessel areaх100. Lesion-specific ischemia by FFR was defined as a value ≤0.8. Results: In quantitative analysis area under the receiver operating characteristic curves (AUC) value of %DS, %AS, MLD, MLA, and PB for prediction of ischemia were 0.72 (95% confidence interval (CI) 0.68-0.77, p Conclusions: Quantitative plaque assessment using CCTA could predict lesion-specific ischemia with good discrimination. Plaque burden showed incremental value over % area stenosis for ischemia prediction.