Minimally invasive fibrillating mitral valve replacement for patients with advanced cardiomyopathy: a safe and effective approach to treat a complex problem

Abstract

Objective: The optimal management of mitral regurgitation (MR) in patients with cardiomyopathy has been controversial. Minimally invasive fibrillating mitral valve replacement (mini-MVR) might limit postoperative morbidity and mortality by minimizing recurrent MR. We hypothesized that mini-MVR with complete chordal sparing would offer low mortality and halt left ventricular (LV) remodeling in patients with severe cardiomyopathy and severe MR.

Methods: From January 2006 to August 2009, 65 patients with an LV ejection fraction (LVEF) of ≤35% underwent mini-MVR. The demographic, echocardiographic, and clinical outcomes were analyzed.

Results: The operative mortality compared with the Society of Thoracic Surgeons-predicted mortality was 6.2% versus 6.6%. It was 5.6% versus 7.4% for patients with an LVEF of ≤20% and 8.3% versus 17.9% among patients with a Society of Thoracic Surgeons-predicted mortality of ≥10%. At a median follow-up of 17 months, no recurrent MR or change in the LV dimensions or LVEF had developed, but the right ventricular systolic pressure had decreased (P=.02). At the first postoperative visit and latest follow-up visit, the New York Heart Association class had decreased from 3.0±0.6 to 1.7±0.7 and 2.0±1.0, respectively (P<.0001 for both). Patients with an LVEF of ≤20% and LV end-diastolic diameter of ≥6.5 cm were more likely to meet a composite of death, transplantation, or LV assist device insertion (P=.046).

Conclusions: Our results have shown that mini-MVR is safe in patients with advanced cardiomyopathy and resulted in no recurrent MR, stabilization of the LVEF and LV dimensions, and a decrease in right ventricular systolic pressure. This mini-MVR technique can be used to address severe MR in patients with advanced cardiomyopathy.

Figure 1

Observed versus predicted operative mortality for the entire cohort of patients, for patients with a LVEF ≤ 20%, and for patients with STS predicted mortality ≥10%. EF = ejection fraction; STS = Society of Thoracic Surgery. Using the Wilcoxon signed-rank test, observed operative survival was significantly better than STS predicted survival for the entire cohort (p < 0.001), patients with EF ≤ 20% (p = 0.001), and patients with STS predicted mortality ≥ 10% (p = 0.03).

Figure 2

Freedom from Death or Transplant in patients with LVEF ≤ 20% and LVEDD ≥ 6.5cm.