Video-assisted minimally invasive mitral valve surgery: external aortic clamp versus endoclamp techniques.

ABSTRACT

OBJECTIVE: Video-assisted minimally invasive mitral valve surgery can be performed through different approaches. The aim of the study was to report our early results and compare the external transthoracic aortic clamping with the endoaortic balloon occlusion techniques according to our experience. METHODS: Between January 2000 and March 2010, 138 patients (103 women, aged 58.4 ± 10.2 years) underwent video-assisted mitral valve surgery through a right thoracotomy. Cardiopulmonary bypass was instituted by femoral arterial and bicaval cannulation with active venous drainage and normothermia; cardioplegic arrest achieved with intermittent blood cardioplegia. In group A (93 patients, 68 women, aged 58.8 ± 7.8 years, 72 MV replacement, 21 MV repair), aortic clamping was achieved using the external transthoracic aortic clamp. In group B (45 patients, 35 women, aged 58.1 ± 11.4 years, 33 MV replacement, 12 MV repair), aortic clamping was achieved with endoaortic balloon occlusion. RESULTS: Intraoperative procedure-associated problems were experienced in one patient (0.7%) in group A (one conversion to sternotomy for pleural adhesions and bad exposure). At a mean follow-up of 36 ± 18 months, 135 patients (97.8%) were in New York Heart Association class I to II, with satisfactory echocardiographic follow-up. In group A, two patients had noncardiac-related deaths. No perioperative deaths were observed in both groups. There were four (2.8%) transient ischemic attacks and one (0.7%) peripheral ischemic event (group A) during the early postoperative period. Mitral valve repair patients had a 5-year freedom from reoperation of 100% in both groups. There was no significant difference between the two groups regarding preoperative variables, such as age, sex, New York Heart Association class, and left ventricular ejection fraction (P > 0.05). Postoperative levels of myocardial cytonecrosis enzymes (MB fraction, creatine kinase, and troponine I) as well as operative time, extracorporeal circulation, and aortic cross-clamping times or ventilation and intensive care unit times were not significantly different between the two groups (P > 0.05). More microembolic events were observed in group A than in group B (total 143.4 ± 30.6 per patient vs 78.9 ± 28.6 per patient) by means of continuous automated intraoperative transcranial Doppler evaluations (P < 0.05) applied to part of population. CONCLUSIONS: Both techniques proved safe and comparable with low risk of morbidity and mortality. Patients undergoing endoclamp technique resulted to be less subject to embolism.