LEFT-VENTRICULAR MASS, SERUM ELECTROLYTE LEVELS AND CARDIAC-ARRHYTHMIAS IN PATIENTS WITH MILD HYPERTENSION TREATED WITH CILAZAPRIL OR HYDROCHLOROTHIAZIDE

Thirty-five patients with mild hypertension (WHO Class I) participated in a double-blind cross-over study involving two 8-week periods of tr eatment with cilazapril 2.5-5 mg once daily or hydrochlorothiaside 25- 50 mg once daily, in each case preceded by a 4-week placebo period. Th irty-two patients completed the study, the aim of which was to compare the effects of the drugs on serum electrolyte levels, left ventricula r mass and cardiac arrhythmias, as assessed by echocardiography and 48 -h Holter monitoring. Both drugs significantly reduced systolic (P < 0 .01) and diastolic (P < 0.001) blood pressures (comparisons with place bo periods). Cilazapril and hydrochlorothiazide had opposite effects o n ventricular ectopic activity. The beneficial effect of cilazapril on ventricular extrasystole counts correlated significantly (P < 0.001) with the reduction of left ventricular mass index. Hydrochlorothiazide had no effects on left ventricular mass or diastolic function. Serum potassium values were significantly (P < 0.001) reduced by hydrochloro thiazide but there was no correlation between changes in potassium lev els and changes in ventricular ectopic activity. The results of the st udy suggest that hydrochlorothiazide and cilazapril were equally effec tive in reducing blood pressure, but only cilazapril reduced left vent ricular hypertrophy and suppressed ventricular ectopic activity.