Excessive leaflet tissue in mitral valve repair for isolated posterior leaflet prolapse-leaflet resection or shortening neochords? A propensity score adjusted comparison.

Background: Chordal replacement techniques are progressively used to treat posterior mitral valve leaflet (PMVL) prolapse while leaflet resection remains commonly in use to address excessive leaflet tissue. For excessive tissue in height, shortening neochords can be used alternatively. Use of chordal replacement techniques has been suggested to result in lower diastolic transvalvular gradients, higher freedom from reoperation and improved left ventricular function.

Methods: From 1/2005 to 12/2016, 150 patients underwent valve repair for isolated PMVL prolapse with excessive tissue. Excessive tissue in height was treated by leaflet resection (N.=99) or shortening neochords (N.=51). Excessive tissue in width was always resected. Logistic regression was used to generate propensity scores for risk-adjusted comparison.

Results: Two patients died postoperatively. In the Neochords group, resection of excessive tissue in width was still needed in 28 (55%) cases. Postoperative echocardiography demonstrated residual (≥2+) mitral regurgitation in 2/150 patients (Resect group). No differences in anuloplasty ring size, postoperative diastolic transvalvular gradients or left ventricular function were observed. Median clinical follow-up duration was 4.4 (IQR 2.0-7.0; 98% complete) years. There was no inter-group difference in overall survival or freedom from reintervention. Mean echocardiographic follow-up was 3.0 (IQR 1.2-5.4; 93% complete) years. In the matched population, the 6-year freedom from recurrent mitral regurgitation rates were 91.3% (95% CI: 81.9-100%) and 97.2% (95% CI: 91.9-100%) for the Resect and Neochords group, respectively (P=0.43).

Conclusions: Both leaflet resection and shortening neochords provide a valuable tool to address excessive PMVL height. Repair durability is excellent regardless of the technique utilized.