Echocardiographic and angiographic assessment of paravalvular regurgitation after TAVI: optimizing inter-technique reproducibility

Abstract

Aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) is often first diagnosed by angiography and then confirmed and followed-up by transthoracic echocardiography (TTE). Consistency between both methods is important for follow-up. We sought to determine inter-technique reproducibility of the assessment of paravalvular AR after TAVI. The study included 165 patients treated with a self-expanding bioprosthesis and had angiography and TTE performed at a median interval of 4 days. TTE parameters of AR severity included VARC score (the average AR grade determined by the echocardiographic VARC-II criteria), pressure half time (PHT), regurgitation jet features in long-axis views (LAX score) and colour Doppler (CD) score (=paravalvular AR jet circumferential extent (%) + LAX score). Using receiver-operating characteristics curves, the cut-points that best defined an angiographic >mild AR were identified.On TTE, AR was paravalvular in all cases, multi-jet in 28%, and predominantly (64%) detected in the commissural region between the right and left coronary sinuses. Using VARC-II criteria (combining at least two), TTE agreed with angiographic classification in 53% of cases (k = 0.14). Greater than mild AR could better be defined by one of the following combinations of criteria: (i) LAX score >4.25 and VARC-II score >1.33; (ii) CD score >11.5 and PHT <400 ms. The combination of the CD score with PHT gave the best sum of sensitivity, specificity, positive, and negative predictive values. Agreement between angiography and TTE (using the VARC-II criteria) in the grading of post-TAVI AR is modest, and this might have contributed to the inconsistency of data on the rate and fate of paravalvular AR. Inter-technique reproducibility can be improved using a combination of CD and hemodynamic parameters.