Mitral regurgitation in patients referred for transcatheter aortic valve implantation using the Edwards Sapien prosthesis: mechanisms and early postprocedural changes.

Background: Transcatheter aortic valve implantation (TAVI) is an alternative to conventional surgery in high-risk patients with severe aortic stenosis (AS), but data regarding mitral regurgitation (MR) characteristics and changes after TAVI are sparse.
Methods: A total of 254 patients with severe AS referred for TAVI were prospectively enrolled. Comprehensive echocardiography was performed at baseline and at 7 days and 1 month in patients who underwent TAVI. MR was semiquantitatively graded from 0 to 4. Overlap of the anterior mitral leaflet and the device was measured using transesophageal echocardiography immediately after TAVI.
Results: At screening, MR was absent in 26%, grade 1 in 44%, grade 2 in 25%, and grade ≥3 in 5% and was organic in 68% and functional in 32%. TAVI was finally performed using the Edwards Sapien valve in 119 patients, including four with MR grade ≥ 3. MR grade significantly decreased at 7 days (P = .003) but remained unchanged at 1 month (P = .55), whereas reverse remodeling occurred only at 1 month (improvements in left ventricular [LV] end-systolic diameter and ejection fraction; P < .05 for both). MR changes over time significantly differed according to ejection fraction and LV diameters (all P values for interaction < .005) but not according to aortic mean gradient, MR etiology, or overlap of the anterior mitral leaflet and the device (all P values for interaction > .15).
Conclusions: In patients referred for TAVI, MR is common, mainly organic, and rarely severe. After TAVI, MR improved within 7 days in both organic and functional MR, was not influenced by overlap of the anterior mitral leaflet and the device, but was associated with improvement in LV ejection fraction. Possible MR improvement should be taken into account in patient selection for TAVI especially, in cases of LV dysfunction or enlargement and MR of borderline severity.
(Copyright © 2012 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.)