Background:Severe mitral regurgitation is a common clinical entity that can lead to progressive, irreversible
left ventricular dysfunction, and thus should be corrected in proper stage of life. Authors have conducted this
investigation to assess left ventricular function after mitral valve operation and to determine the predicting
factors. Methods and Results:The echocardiographic parameters, specifically left ventricular ejection fraction,
shortening fraction, end-systolic dimension and volume, and end-diastolic dimension and volume were measured
in preoperative and postoperative period of congenital mitral regurgitation patients (n=60), between March
1992 and March 1998. After correction of severe mitral regurgitaion, left ventricular ejection fraction and
shortening fraction decreased significantly (p<0.001 and p<0.05 respectively). Furtheremore, after reoperation
of recurred mitral regurgitation, left ventricular ejection fraction and shortening fraction decreased significantly
(p<0.05). Left ventricular ejection fraction and shortening fraction in mitral valve reoperation group (n=23)
is significantly lower than those in non-reoperation group (n=37) in both preoperative and postoperative
period (p<0.05). Left ventricular ejection fraction and shortening fraction is also significantly lower in mitral
valve replacement group (n=20) than in mitral valvuloplasty group (n=40)(p<0.05). Severe postoperative
left ventricular dysfunction led to dilated cardiomyopathy in 5 patients. Postoperative left ventricular end
systolic dimension increased significantly in reoperation group and DCMP group respectively (p<0.05).
Conclusion:After surgical correction of mitral regurgitation, left ventricular dysfunction is frequent and
carries a poor prognosis. Postoperative left ventricular dysfunction can be predicted by preoperative ejection
fraction, shortening fraction and systolic diameter. Therefore surgical therapy before the onset of left
ventricular dysfunction is recommended. (Korean Circulation J 2000;30(6):737-744)