RESUMO
BACKGROUND AND AIM OF THE STUDY: Mitral valve surgery in the presence of poor left ventricular (LV) function is associated with higher mortality. One surgeon's (S. K. N.) evolving practice of mitral valve surgery on the beating heart using normothermic cardiopulmonary bypass (CPB) in a cohort of patients is described. METHODS: Between July 2000 and December 2002, 23 patients (13 men, 10 women; mean age 68.6 +/- 4.8 years; range: 54-81 years) with mitral regurgitation and LV ejection fraction <30% undergoing isolated mitral valve repair (n = 4) or replacement (n = 19) were investigated. All patients received maximal drug therapy. Among patients, 17 were in NYHA class III, and six in class IV. RESULTS: The mean duration of follow up was 17 +/- 14 months, and was complete for all survivors. The visual field of the on-pump beating heart was equal to that of conventional valvular surgery, and technical accuracy was not compromised. The mean ICU and hospital stays were 2.4 +/- 1.3 days and 8.9 +/- 2.6 days, respectively. Mean CPB time was 74.3 +/- 14.8 min. Thirty-day mortality was significantly lower (8.7%) when compared to mean Euroscore-predicted mortality for this high-risk group (16.9%; p <0.001). The medium-term one- and two-year survivals were 87% and 78%, respectively. Mean NYHA class was improved, from 3.6 +/- 0.5 preoperatively to 1.9 +/- 0.7 at follow up (p = 0.037). CONCLUSION: On-pump, beating-heart mitral valve surgery is a good option in patients with poor LV function, and is advantageous as conditions for the heart are more physiological with a beating tonus than with cardioplegia.
