Minimally Invasive Mitral Valve Surgery Provides Excellent Outcomes Without Increased Cost: A Multi-Institutional Analysis

Abstract

Minimally invasive mitral valve surgery (mini-MVR) has grown in popularity. Although single centers have reported excellent outcomes, data on real-world outcomes and costs of mini-MVR are limited. Moreover, mini-MVR has been criticized as adding additional cost without clear benefit. We hypothesized that mini-MVR provides superior outcomes with incremental increased costs in a multi-institutional cohort. Records for patients undergoing mitral valve surgical procedures with or without atrial ablation from 2011 to 2014 were extracted from a multi-institutional, regional Society of Thoracic Surgeons database and stratified according to right chest approach/minimally invasive or conventional sternotomy. Patients undergoing coronary artery bypass grafting or other concomitant procedures were excluded. Patients undergoing isolated mitral surgical procedure were propensity matched according to factors, including age, comorbidities, and preoperative laboratory values; clinical outcomes and cost differences were assessed by approach. A total of 1,304 patients underwent mitral operations, including 425 (32.6%) by minimally invasive approach. In the propensity-matched analysis (n= 355 per group), patients undergoing mini-MVR had similar rates of mortality, stroke, and other complications compared with conventional MVR. Meanwhile, patients with mini-MVR experienced shorter intensive care unit and hospital lengths of stay and fewer transfusions. Importantly, total hospital costs were no different between the two matched groups. Compared with conventional sternotomy, mini-MVR in the "real world" demonstrated no differences in rates of major morbidity, but it was associated with shorter length of stay and fewer transfusions. Contrary to our hypothesis, mini-MVR can be performed with similar total hospital costs as conventional sternotomy. In summary, minimally invasive mitral surgical procedure in select patients can provide superior outcomes without increased cost.