Minimally invasive mitral valve surgery is a very safe procedure with very low rates of conversion to full sternotomy.

OBJECTIVES: Over the past 10 years, minimally invasive mitral valve surgery (MI-MVS) has become the standard approach for treatment of atrio-ventricular valve disease in specialized centres. This approach uses a right lateral mini-thoracotomy and femoral cannulation for cardiopulmonary bypass. In a very low number of patients, conversion to full sternotomy may be necessary.

METHODS: A total of 3125 patients underwent MI-MVS between 1999 and 2010 at our institution. Conversion to full sternotomy was required in 1.0% (n=34) of all patients. Patient data, including intraoperative course and postoperative outcome, were collected. Follow-up data were collected in a prospective database and analysed retrospectively.

RESULTS: A total of 34 patients underwent conversion to full sternotomy during MI-MVS. The mean age of patients was 67.9±9.5 years, and 17 patients were female (50%). The main reasons for conversion were as follows: major bleeding in 18 patients (52.9%); severe pulmonary adhesions in six patients (17.6%); and aortic dissection in five patients (14.7%). The clinical outcome of these patients was impaired, with the development of acute renal failure in 13 patients (38.2%) and respiratory failure in 10 patients (29.4%). Operative mortality (30 days) was 23.5% (eight patients). The reason for death in all these patients was low cardiac output syndrome with subsequent multi-organ failure.

CONCLUSIONS: This large series shows that MI-MVS can be performed with very low complication rates. In the experience of this large single-centre study, conversion to full sternotomy was necessary in only 1% of all patients. If conversion is indicated, however, it is associated with a high operative mortality.