Minimally Invasive Video-assisted Mitral Valve Surgery: a 12-year, 2-center Experience in 1178 Patients

Objective: To review a 2-institution experience with minimally invasive mitral valve surgery over a 12-year period.

Methods: We prospectively collected data on all patients having minimally invasive mitral valve surgery through a right minithoracotomy between May 1996 and May 2008.

Results: A total of 1178 patients included 941 (79.9%) patients having mitral valve repair and 237 (20.1%) having mitral valve replacement. The mean age was 61.1 +/- 13.9 years, mean ejection fraction was 52.8% +/- 12.1%, and 221 patients (18.8%) were having reoperations. Operative mortalities for mitral valve repair and mitral valve replacement were 2.1% and 4.6%, and for isolated primary MVP and MVR were 0.2% and 3.6%, respectively. Repair techniques included annuloplasty (98.2%), leaflet resection (40.7%), sliding plasty (21.0%), chordal transfer (9.0%), and neochordae placement (7.4%), with no or trivial residual MR in over 97% of patients. In patients having mitral valve replacement, a bioprosthesis was placed in 101 patients (42.6%) and a mechanical valve in 136 (57.4%). Concomitant procedures included atrial fibrillation ablation (22.5%), tricuspid valve surgery (5.4%), and atrial septal defect closure (9.4%). Nineteen patients (1.6%) experienced intraoperative conversion to sternotomy. Twenty-two patients (1.9%) had a reoperation at a mean of 732 +/- 1014 days. Independent predictors of in-hospital mortality included New York Heart Association class III/IV (odds ratio 3.62), diabetes (odds ratio 2.81), bypass time > 180 minutes (odds ratio 2.63), preoperative atrial fibrillation (odds ratio 2.53), and age > 70 years (odds ratio 2.29). Prior cardiac surgery was not a significant predictor of mortality.

Conclusions: Video-assisted mitral valve surgery is safe with high rates of repair, low morbidity, and excellent outcomes. Reoperation after previous median sternotomy is not an independent predictor of mortality with this approach. Operative risk is increased if surgery is delayed until the onset of atrial fibrillation.