Effect of the preservation of annulo-papillary continuity on left ventricular ejection fraction after mitral valve replacement. A clinical randomized study on patients affected by rheumatic valve disease.

This perspective study has been designed to evaluate the modifications induced on left ventricular contractility by the interruption of annulo-papillary continuity during mitral valve replacement in patients with rheumatic valve disease. Patients with associated cardiac diseases were not admitted to the study. Sixty-nine patients entered the trial, each patient was randomly assigned to mitral valve replacement either with preservation of the annulo-papillary continuity (PAPC) or with excision of all the chordae (EC). Patients with mitral stenosis (MS) and combined mitral disease (MS & R) were considered separately. The four groups were similar regarding preoperative characteristics including the radioisotopic left ventricular ejection fraction (LVEF). All the patients had the mitral valve replaced with a bileaflet prosthesis fixed by interrupted mattress sutures in the supra-annular position; the methods of anesthesia, cardiopulmonary bypass and myocardial preservation were similar in all patients. In the patients of the two EC groups a complete excision of the mitral valve was performed. In the patients of the PAPC groups a modified Miki's technique was used to preserve annulo-papillary continuity; in eight cases with heavy calcification of the subvalvular apparatus, after total excision of the mitral valve, PTFE sutures were used to reconnect the annulus to the papillary muscles. After 6 months' follow-up, 2D and Doppler echocardiography was completed in each patient to confirm the absence of any prosthetic leakage and left ventricular outflow tract obstruction. (LVOT).(ABSTRACT TRUNCATED AT 250 WORDS)