Exercise-induced changes in mitral regurgitation in patients with prior myocardial infarction and left ventricular dysfunction: relation to mitral deformation and left ventricular function and shape.

AIMS: The aim of this study was to assess the relationship between exercise-induced changes in mitral regurgitation (MR) and echocardiographic characteristics of mitral deformation, global left ventricular (LV) function and shape at rest and after exercise. METHODS AND
RESULTS: Forty consecutive patients with ischaemic MR due to prior myocardial infarction (MI), ejection fraction <45% in sinus rhythm underwent exercise-echocardiographic testing. Exercise-induced changes in effective regurgitant orifice (ERO) were compared with baseline and exercise-induced changes in mitral deformation and global LV function and shape. There was significant correlation between exercise-induced changes in ERO and changes in coaptation distance (r=0.80, P<0.0001), tenting area (r=0.79, P<0.0001) and mitral annular diameter (r=0.65, P<0.0001), as well as in end-systolic sphericity index (r=-0.50, P=0.001, respectively), and wall motion score index (r=0.44, P=0.004). In contrast, exercise-induced changes in ERO were not related to the echocardiographic features at rest. By stepwise multiple regression model, the exercise-induced changes in mitral deformation were found to independently correlate with exercise-induced changes in ERO (generalized r(2)=0.80, P<0.0001).
CONCLUSION: Exercise-induced changes in severity of ischaemic MR in patients with LV dysfunction due to prior MI were independently related to changes in mitral deformation.