A systematic review and meta-analysis of chordal replacement versus leaflet resection for isolated posterior mitral valve prolapse.

INTRODUCTION: Chordal replacement (Chord MVr) for isolated posterior mitral valve prolapse allows for preservation of the native mitral valve apparatus. The potential benefits of this approach, as compared with leaflet resection (Resection), are not clearly defined.

EVIDENCE ACQUISITION: A systematic review and meta-analysis was conducted on operative, clinical, and echocardiographic outcomes. Risk ratios (RR) were calculated by the Mantel-Haenszel method under a fixed or random effects model, as appropriate.

EVIDENCE SYNTHESIS: Eight studies were included, with a total of 1922 patients (Chord MVr, N.=835; Resection, N.=1087). Baseline characteristics were similar, except for a higher incidence of atrial fibrillation in the Chord MVr group (15.5% versus 9.9%, P=0.03), and a slightly greater mitral regurgitation grade in the Resection group (3.5 versus 3.4, P=0.008). P2 segment prolapse was the most common pathology, however, patients undergoing Chord MVr had a higher incidence of multi-segment prolapse (32.1% versus 13.9%, P=0.0006). There was no difference in operative mortality (1.1% for both) or perioperative complications. At a mean follow-up of 2.9±2.8 years (median=2.8 years, IQR 1.6-4.4), Chord MVr was associated with a lower risk of reoperation (1.1% versus 4.3%; RR 0.26, 95% CI 0.12-0.56, P=0.0007), and similar survival and recurrence of moderate mitral regurgitation, when compared with Resection. Finally, a lower transmitral gradient (2.5 versus 2.8 mmHg, P=0.0004) and larger orifice area (3.2 versus 3.0 cm2, P=0.002) were observed with Chord MVr.

CONCLUSIONS: At 2.9-year follow-up, Chord MVr for isolated posterior mitral valve prolapse was associated with a lower reoperation rate and favorable valve hemodynamics, when compared with leaflet resection.