Should a regurgitant mitral valve be replaced simultaneously with a stenotic aortic valve?

Mitral valve regurgitation frequently accompanies aortic valve stenosis. It has been suggested that mitral regurgitation improves after aortic valve r eplacement alone and that the mitral valve need not be replaced simultaneou sly Furthermore, mitral regurgitation associated with coronary artery disea se, particularly in patients with poor left ventricular function, shows imm ediate improvement after coronary artery bypass grafting. We studied 60 consecutive patients with aortic stenosis and mitral regurgit ation to determine the degree of improvement in mitral regurgitation after aortic valve replacement alone versus aortic valve replacement combined wit h coronary artery bypass grafting. Thirty-six of the patients had normal co ronary arteries (Group 1), the other 24 had symptomatic coronary artery dis ease requiring bypass surgery (Group 2). Echocardiography was performed pre operatively, 1 week postoperatively, and at follow-up. In Group 1, left ventricular ejection fraction did not improve early or at 2.5 months postoperatively, but mitral regurgitation improved gradually dur ing follow-up. In Group 2 mitral regurgitation showed improvement 1 week po stoperatively (p < 0.001), and left ventricular ejection fraction was impro ved at 2.5 months. We conclude that patients with aortic valve stenosis and mild-to-severe mit ral regurgitation, without echocardiographic signs of chordal or papillary muscle rupture and without coronary artery disease, should undergo aortic v alve replacement alone. The mitral regurgitation will remain the same or im prove. For patients with coexisting coronary artery disease, simultaneous a ortic valve replacement and coronary artery bypass grafting are imperative; however, the mitral valve again requires no intervention, since mitral reg urgitation improves significantly after the other 2 procedures.