Mitral valve repair versus replacement for isolated non-ischemic mitral regurgitation in patients with preoperative left ventricular dysfunction. A long-term follow-up echocardiography study

Abstract

The aim of this study was to evaluate LV function, by means of echocardiography, after mitral valve repair (MVr) or mitral valve replacement (MVR) in patients (pts) with chronic degenerative mitral regurgitation (MR) and depressed LV systolic function during a 6-years follow-up (FU) period. Forty-five pts with moderately severe or severe MR and preoperative EF<or=50% were divided into 2 groups: MVr group (27 pts, 19 men-8 women, aged 62+/-10 years) and MVR group (18 pts, 8 men-10 women, aged 60+/-12 years). The cause of MR was myxomatous mitral valve disease (MVr/MVR: 16/8), endocarditis (0/4) and degenerative mitral valves with ruptured chordae tendineae (11/6). All pts underwent transthoracic echocardiography preoperatively, postoperatively and annually during the FU period (6+/-3 years). In MVr group, 5 pts died, 5 were lost to FU and 2 pts underwent MVR due to MVr failure. In MVR group, 6 pts died, 3 were lost to FU and 1 was re-operated due to prosthetic valve endocarditis. Atrial fibrillation was similar between the 2 groups. MVr pts demonstrated significant LVEDD decrease postoperatively which was persistent during FU (p<0.05). LVESD also decreased (p<0.05), VTI improved (p<0.05), while FS and EF showed a trend to improve. In MVR pts, LVEDD was decreased (p<0.05) but increased during FU (p<0.05) and LVESD remained high, resulting in a decrease of FS and EF (p<0.05). VTI remained unchanged (p=NS). MVr in pts with non-ischemic MR and preoperative LV dysfunction achieves better preservation of LV systolic indices than MVR, probably due to preservation of the subvalvular apparatus and LV geometry.