DETERMINANTS OF LEFT-VENTRICULAR FUNCTION BEFORE AND AFTER REGRESSIONOF MYOCARDIAL HYPERTROPHY IN HYPERTENSION

Using digitized M-mode echocardiograms, we evaluated the determinants of left ventricular (LV) systolic and diastolic function in 30 hyperte nsives with LV hypertrophy (LV mass > 230 g and normal LV diastolic di ameter), before (LV mass 319 +/- 26 g) and after normalization of LV m ass (196 +/- 21 g) by antihypertensive treatment with angiotensin conv erting enzyme inhibitors. As a control group we selected 50 normal sub jects. Using multiple regression analysis we studied the relative role of preload (LV end-diastolic diameter), afterload (end-systolic wall stress), inotropic state (systolic pressure/endsystolic LV diameter ra tio), and LV mass on LV systolic (peak shortening rate of LV diameter) and diastolic function (peak lengthening rate of LV diameter). The ma jor determinant of systolic function was the end-systolic stress in hy pertensives before treatment and the systolic pressure/end-systolic LV diameter ratio in normals and in hypertensives after treatment. The m ajor determinant of diastolic function was LV mass in hypertensives be fore treatment and end-systolic stress in normals and in hypertensives after normalization of LV mass by treatment. Preload seems not to inf luence LV function in normals and in hypertensives with normal LV diam eter. The inotropic state is the major determinant of systolic functio n in normals and in hypertensives after treatment, whereas this role i s played by afterload in hypertensives before treatment. The diastolic function is primarily influenced by afterload in normals and in hyper tensives after regression of myocardial hypertrophy, whereas in hypert ensives with myocardial hypertrophy LV mass is the major determinant o f diastolic function.