Ventricular and myocardial function following treatment of hypertension

This study assesses and evaluates left ventricular (LV) contractile functio n after treatment of hypertension, with an emphasis on LV midwall mechanics . Although prior studies have assessed cardiac function after hypertension treatment, none has performed an analysis of LV midwall mechanics. The Vete rans Affairs Study of monotherapy in hypertension was a study large enough to permit analysis of midwall mechanics across a wide spectrum of mass chan ges accompanying hypertension treatment. LV chamber function was assessed b y computing fractional shortening at the endocardial surface; LV midwall sh ortening was used to define myocardial function. Both shortening indexes we re related to end-systolic circumferential stress in the entire population by partitioning values of mass and relative wall thickness changes. Two hun dred sixty-eight patients were studied at baseline and again after a 1- or 2-year period. In the entire group, there was no significant change in circ umferential shortening either at the endocardium (38 +/- 8% at baseline vs 37 +/- 7% at follow up, p = 0.29) or in shortening at the midwall (20 +/- 3 % vs 20 +/- 3%, p = 0.53). However, 83 patients had a reduction in relative wall thickness and an increase in midwall shortening. The change in midwal l shortening was significantly related to changes in relative wall thicknes s (r = -0.53, p = 0.0001). Thus, reductions in LV mass associated with anti hypertensive therapy are generally not accompanied by a decrement in LV cha mber or myocardial function. Improvement in midwall shortening is more clos ely related to normalization of LV geometry than to reduction in LV mass. ( C) 2001 by Excerpta Medica, Inc.