Prevention of left ventricular outflow tract obstruction in transapical mitral valve replacement: the MitraCut procedure.

Abstract

Background: The MitraCut procedure employs beating heart transapical (TA) cannulation and endoscopic scissors for dividing the anterior mitral leaflet (AML) to prevent left ventricular outflow tract (LVOT) obstruction in transapical transcatheter mitral valve replacement (TA-TMVR).

Aims: We present the first multicentre experience of the MitraCut procedure prior to TA-TMVR to prevent LVOT obstruction.

Methods: In 6 European centres, the clinical outcomes of all 13 high-risk patients who had undergone the MitraCut procedure during TA-TMVR procedures were retrospectively reviewed regarding technical success, procedural details and outcome.

Results: The MitraCut procedure was successfully completed in 11 patients with 1 cutting attempt, while 2 patients had 2 cutting attempts, with an average procedure duration of 9.0±5.4 min. No patient demonstrated postoperative LVOT obstruction, and all mitral valve (MV) prostheses were competent throughout the follow-up period. However, 1 patient developed a MitraCut-related paravalvular leak (PVL; technical success rate: 12/13). The mean LVOT gradient was 3.9±4.4 mmHg directly after valve expansion and 3.6±3.1 mmHg at follow-up. In-hospital and 30-day mortality were 0%. One patient experiencing MitraCut-related PVL was successfully treated by interventional PVL closure (reintervention rate: n=1). One patient died at 47 days due to cardiac arrhythmia, unrelated to the AML-directed procedure. The mean follow-up at the time of data analysis was 52±34 days.

Conclusions: The MitraCut procedure was effective and reproducible for preventing potential LVOT obstruction in TA-TMVR patients during its initial exploration in 6 European hospitals. Considerations regarding the scissors' characteristics, their handling and cut length are mandatory for safe performance of the procedure.