Mid-Term Outcomes of Beating Heart Mitral Valve Replacement in Secondary Mitral Regurgitation with Poor Left Ventricular Function

Abstract

Background: Ischemic cardiomyopathy patients often have a severely atherosclerotic ascending aorta and low cardiac function. In these patients, aortic cross-clamping and cardiac arrest increase the risk of postoperative strokes and low cardiac output syndrome. Objective: To evaluate the short and medium term outcomes of clampless beating heart mitral valve replacement in patients with secondary mitral regurgitation and a poor left ventricular function. Method: Here we describe two male patients, aged 71 and 54 years, with severe secondary mitral regurgitation and impaired left ventricular ejection fraction (LVEF) (24% and 30%, respectively). On-pump beating-heart mitral valve replacement with total chordal sparing was performed without aortic cross-clamping, through a full sternotomy approach. Results: Weaning from cardiopulmonary bypass, which lasted 43 and 52 minutes respectively, was easily achieved without the use of positive inotropes or vasopressors. The duration of mechanical ventilation (3 and 6 hours, respectively) and intensive care (24 and 48 hours, respectively) was short, considering the advanced stage of cardiomyopathy. Both patients had no postoperative neurological disorder. After a mean follow-up of 66 months (84 and 48 months, respectively), both patients were asymptomatic, without prosthetic valve dysfunction and their LVEF reached 42% and 51%, respectively. Conclusion: Beating heart mitral valve replacement, with total preservation of subvalvular apparatus, and without cross-clamping of the aorta, preserves left ventricular systolic function in the short and long-term, and reduces embolic events due to aortic manipulation. This technique can improve the outcomes of surgery for secondary mitral regurgitation in cases of severe left ventricular dysfunction.