Effect of minimally invasive mitral valve surgery compared to sternotomy on short- and long-term outcomes: a retrospective multicentre interventional cohort study based on Netherlands Heart Registration.

Abstract

Minimally invasive mitral valve surgery (MIMVS) has been performed increasingly for the past 2 decades; however, large comparative studies on short- and long-term outcomes have been lacking. This study aims to compare short- and long-term outcomes of patients undergoing MIMVS versus median sternotomy (MST) based on real-world data, extracted from the Netherlands Heart Registration. Patients undergoing mitral valve surgery, with or without tricuspid valve, atrial septal closure and/or rhythm surgery between 2013 and 2018 were included. Primary outcomes were short-term morbidity and mortality and long-term survival. Propensity score matching analyses were performed. In total, 2501 patients were included, 1776 were operated through MST and 725 using an MIMVS approach. After propensity matching, no significant differences in baseline characteristics persisted. There were no between-group differences in 30-day mortality (1.1% vs 0.7%, P = 0.58), 1-year mortality (2.6% vs 2.1%, P = 0.60) or perioperative stroke rate (1.1% vs 0.6%, P = 0.25) between MST and MIMVS, respectively. An increased rate of postoperative arrhythmia was observed in the MST group (31.3% vs 22.4%, P < 0.001). A higher repair rate was found in the MST group (80.9% vs 76.3%, P = 0.04). No difference in 5-year survival was found between the matched groups (95.0% vs 94.3%, P = 0.49). Freedom from mitral reintervention was 97.9% for MST and 96.8% in the MIMVS group (P = 0.01), without a difference in reintervention-free survival (P = 0.30). The MIMVS approach is as safe as the sternotomy approach for the surgical treatment of mitral valve disease. However, it comes at a cost of a reduced repair rate and more reinterventions in the long term, in the real-world.