CMR to stratify post-TAVR paravalvular leak in patients with suboptimal echocardiography

Abstract

Background Despite extensive pre-procedure evaluation, greater than mild paravalvular leak (PVL) occurs in over 10% of patients undergoing transcatheter aortic valve replacement (TAVR) and is associated with worse outcomes. Echocardiography, the standard method of imaging PVL, often has limited utility due to frequently multiple eccentric regurgitant jets. Acoustic shadowing from the valve stent and native aortic valve calcification may lead to further underestimation of PVL. Cardiovascular magnetic resonance (CMR) is considered the gold standard for quantification of valvular regurgitation. We evaluated the utility of CMR to grade PVL severity and predict outcomes in patients with suboptimal echocardiography. Methods Seventeen non-operative post-TAVR patients (NYHA class III-IV; age 84 ± 5 yrs) underwent CMR due to PVL and symptoms out of proportion to echocardiographic findings or suboptimal echocardiographic study. CMR was performed on a Siemens Avanto 1.5 T with velocity phase imaging in the ascending aorta for flow quantification. CMR PVL severity was graded by regurgitant fraction (RF; mild≤20%, moderate 21-39%, severe ≥40%). Short- and intermediate-term follow-up was conducted after CMR. Patients were followed-up for symptoms and a composite outcome of repeat invasive therapy, heart failure hospitalization, or death.