Factors for development of late significant tricuspid regurgitation after mitral valve replacement: the impact of subvalvular preservation.

Objective: Development of late significant tricuspid regurgitation (TR) after successful mitral valve replacement (MVR) is not infrequent. The impact of different aetiologies or diverse surgical procedures has not been adequately investigated. We studied the influence of subvalvular preservation techniques during MVR on the incidence of late TR.
Methods: A total of 801 patients with grade ≤ 2+/4+ preoperative TR underwent MVR without associated tricuspid procedures from January 1994 to August 2008. In 595 patients, only posterior mitral leaflet preservation was performed (group A). In the remaining 206 patients, both anterior and posterior leaflets were retained (group B). Postoperative development of significant TR was defined as a TR increase by more than one grade from preoperative or final TR grade ≥ 3+/4+ at follow-up.
Results: The global incidence of postoperative significant TR was 8.6%, with higher incidence in females (9.4% vs 6.7%, p=0.12), rheumatic disease (9.7% vs 6.5%, p=0.07), patients with previous AF (11.8% vs 3.8%, p<0.001) and, especially, in group A (10.8% vs 2.4%, p<0.001). The Maze procedure was protective in patients with AF (the incidence with and without associated Maze was 6.7% vs 13.2%, p=0.04). Preoperative left-atrial diameters were higher in patients with postoperative development of TR (56 ± 9 mm vs 51 ± 12 mm, p=0.01). Group A (p=0.04) and preoperative atrial fibrillation (p=0.001) were significant predictors of late postoperative TR. Late functional TR decreased free survival from chronic heart failure.
Conclusions: Several clinical and operative factors are associated with the development of significant TR after MVR. Although early surgical intervention for TR may be recommended in selected patients, complete subvalvular preservation of the mitral valve and routine surgical ablation of atrial fibrillation can significantly reduce its incidence.
(Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)