Is posterior leaflet preservation in the surgical treatment of rheumatic mitral insufficiency without left ventricular dysfunction necessary?

Preservation of the mitral valve leaflet and tensor apparatus during valve replacement is believed to maintain left ventricular performance. To determine the effect of posterior leaflet preservation in pure severe mitral insufficiency without left ventricular dysfunction 56 patients were operated on between 1993 and 2000. Twenty-three patients underwent mitral valve replacement with posterior chordal preservation and 33 patients underwent mitral valve replacement with chordal transection. Preoperative data in the both groups were similar. After 30days there were no mortalities observed. Dimensions of the left ventricle had significantly decreased within one group, but there was no difference in the other group. The improvement of the functional and cardiac performance in all patients was significant without any difference between the two groups. Actuarial freedom from death was not significantly different at 6yr (P=0.23). To preserve left ventricular function in pure severe mitral regurgitation without left ventricular dysfunction, mitral valve replacement is very effective with or without posterior leaflet preservation. But, it is difficult to suggest that posterior leaflet preservation alone can increase cardiac performance.