Mitral Regurgitation After Transcatheter Aortic Valve Replacement: Prognosis, Imaging Predictors, and Potential Management.

Objectives: This study sought to analyze the clinical impact of the degree and improvement of mitral regurgitation in TAVR recipients, validate the main imaging determinants of this improvement, and assess the potential candidates for double valve repair with percutaneous techniques.
Background: Many patients with severe aortic stenosis present with concomitant mitral regurgitation (MR). Cardiac imaging plays a key role in identifying prognostic factors of MR persistence after transcatheter aortic valve replacement (TAVR) and for planning its treatment.
Methods: A total of 1,110 patients with severe aortic stenosis from 6 centers who underwent TAVR were included. In-hospital to 6-month follow-up clinical outcomes according to the degree of baseline MR were evaluated. Off-line analysis of echocardiographic and multidetector computed tomography images was performed to determine predictors of improvement, clinical outcomes, and potential percutaneous alternatives to treat persistent MR.
Results: Compared with patients without significant pre-TAVR MR, 177 patients (16%) presented with significant pre-TAVR MR, experiencing a 3-fold increase in 6-month mortality (35.0% vs. 10.2%; p < 0.001). After TAVR, the degree of MR improved in 60% of them. A mitral annular diameter of >35.5 mm (odds ratio: 9.0; 95% confidence interval: 3.2 to 25.3; p < 0.001) and calcification of the mitral apparatus by multidetector computed tomography (odds ratio: 11.2; 95% confidence interval: 4.03 to 31.3; p < 0.001) were independent predictors of persistent MR. At least 14 patients (1.3% of the entire cohort, 13.1% of patients with persistent MR) met criteria for percutaneous mitral repair with either MitraClip (9.3%) or a balloon-expandable valve (3.8%).
Conclusions: Significant MR is not uncommon in TAVR recipients and associates with greater mortality. In more than one-half of patients, the degree of MR improves after TAVR, which can be predicted by characterizing the mitral apparatus with multidetector computed tomography. According to standardized imaging criteria, at least 1 in 10 patients whose MR persists after TAVR could benefit from percutaneous mitral procedures, and even more could be treated with MitraClip after dedicated pre-imaging evaluation.
(Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)