P5249Comprehensive invasive and non-invasive assessment of coronary artery lesions with and without hemodynamic significance

Abstract

Abstract Background There is limited knowledge about specific morphological parameters beyond the degree of stenosis to further characterize hemodynamically relevant coronary lesions. Objective The goal of this study was to identify certain morphological or molecular characteristics that distinguish hemodynamically significant from non-significant coronary lesions using various invasive and non-invasive measures. Methods This clinical study included patients with symptoms suggestive of CAD who underwent native T1-weighted CMR and gadofosveset-enhanced CMR as well as invasive coronary angiography between 2015 and 2016. OCT of the culprit vessel to determine the plaque type was performed in a subset of patients. Functional relevance of all lesions was examined using quantitative flow reserve (QFR-Angio). Hemodynamically significant lesions were defined as lesions with a QFR <0.8. Signal intensity (contrast-to-noise ratios; CNRs) on native T1-weighted CMR and gadofosveset-enhanced CMR was defined as a measure for intraplaque hemorrhage and endothelial permeability respectively. Results Overall 13 patients (n=28 coronary segments) were included, whose invasive coronary angiograms projections were eligible for QFR analysis. Segments containing lesions with a QFR <0.8 (n=9) were associated with significantly higher signal enhancement on Gadofosveset-enhanced CMR as compared to segments containing a hemodynamically non-relevant lesions (lesion-QFR>0.8; n=19) (7.0±4.9 vs. 3.0±2.6; p=0.02). No differences in signal enhancement were seen on native T1-weighted CMR (2.1±4.3 vs. 3.3±4.1; p=0.24). 66,7% (4 out of 6) of all vulnerable plaque and 33.3% (2 out of 6) of all non-vulnerable plaque (fibroatheroma) as assessed by OCT were hemodynamically significant lesions. Conclusion The findings of this small feasibility study suggest that hemodynamically significant lesions are more advanced and associated with a higher grade of endothelial permeability while the presence of intraplaque hemorrhage may not be associated with hemodynamically relevant coronary lesions.