Objectives: We sought to review our experience in patients with severely impaired left ventricular function (ejection fraction (EF) ≤ 30%) who underwent minimally invasive mitral valve (MV) surgery (Mini-MV).
Methods: Between 1999 and 2010, a total of 3450 patients underwent Mini-MV surgery at our institution. Of these, 177 had severely impaired left ventricular function (EF < 30%, including ischaemic and non-ischaemic cardiomyopathy). Primary indication for surgery was MV regurgitation in all but 5 patients (2.8%), who were diagnosed with mixed regurgitation and stenosis. Mean age of patients was 67 ± 11 years and 110 were male (62.1%). Mean EuroSCORE predicted risk of mortality was 14.7 ± 13.6%.
Results: MV repair was accomplished in 86.4% of patients (n = 153), and MV replacement was performed in 13.6% (n = 24). Primary MV repair included implantation of a rigid annuloplasty ring (mean size 29.5 ± 2.2 mm) in 95.4% of patients, and additional MV procedures as required. Concomitant procedures consisted of tricuspid valve surgery in 15.3% of patients, atrial fibrillation ablation in 27.1% and atrial septal defect/persistent foramen ovale closure in 5.6%. The duration of cardiopulmonary bypass was 123 ± 64 min and aortic cross-clamp time was 67 ± 27 min. Thirty-day mortality was 7.9%. The mean follow-up time was 3 ± 2.5 years, and the follow-up was 94.0% complete. Ten-year survival was 45.5% (95% CI: 35.2-55.9) for the overall group. The rate of MV-related reintervention was 4%, while heart transplantation was performed in 6%.
Conclusions: Mini-MV surgery in patients with significantly impaired left ventricular function can be performed with a reasonable operative mortality and acceptable long-term survival for this high-risk patient cohort.
Keywords: Heart failure; Minimally invasive mitral valve surgery; Mitral valve dysfunction.