998-120 Left Ventricular Systolic Performance Changes in Mild Hypertensive Subjects Treated with Antihypertensive Monotherapy or Placebo: The Treatment of Mild Hypertension Study (TOMHS)

Few large scale studies have evaluated long term effects of antihypertensive monotherapy (MT) versus placebo (P) on left ventricular (LV) systolic performance. Over a period of 4 years, 844 subjects with mild hypertension (mean BP: 140/91) without cardiac disease were treated with one of 5 MTs or P, all receiving nutritional-hygienic intervention. 2-D directed M-mode echocardiograms evaluated LV function at baseline, 3 months and annually through 4 years. Average changes over 4 years were compared between combined MT groups and P. Average decrease in BP was 15.9/12.3 mmHg in the MT group and 9.1/8.6 mmHg in the P group. for global systolic performance, stroke volume, ejection fraction, and fractional shortening (FS) increased with MT but decreased in P (p l 0.01 (MT vs P). Average change from baseline in stroke volume was –3.0% with P and +1.7% with MT. Cardiac output, stroke work index and minute work index decreased similarly in both MT and P. Peak-and end-systolic stress (ESS) increased significantly more in P than MT (p l 0.01). Total peripheral resistance decreased more in the MT group (p l 0.001). For indexes of contractility, ESS/ES volume index increased more in the P group, FS/ESS increased in MT and decreased in P, and SBP/ES dimension decreased more in the MT group (p l 0.02 for each). These findings suggest that even in mild hypertensives without underlying LV dysfunction, the addition of MT to nutritional-hygienic therapy can produce small, though significant changes in LV performance characteristics.