Ventricular arrhythmias pose a serious risk in patients with
high blood pressure. The concept that
diuretics predispose to life-threatening arrhythmias, however, was originally based solely on observations made in patients with severe
congestive heart failure pretreated with digitalis and not in patients with
high blood pressure. In hypertensive patients, some studies have also indicated that
diuretic therapy may be associated with an increase in
premature ventricular beats, though most have failed to demonstrate a conclusive link between
hypokalemia and the precipitation of such
cardiac arrhythmias. Prospective studies, however, have demonstrated that
diuretic therapy had no effect on the incidence of serious ventricular arrhythmias in hypertensive patients whether they had
left ventricular hypertrophy (LVH) or not, and neither at rest nor during or immediately following dynamic exercise. Correction of
diuretic-induced
hypokalemia similarly had no effect on the incidence of ventricular arrhythmias. In hypertensive patients, LVH is an independent and particularly sinister risk factor for cardiovascular morbidity and mortality, and its regression is now a specific goal of
antihypertensive therapy.
Diuretics have been shown to be at least as effective in that respect as other
antihypertensive agents. The Veterans Administration Cooperative Study Group reported that after 2 years of treatment, only
hydrochlorothiazide of 6
antihypertensive regimens resulted in significant reduction of left ventricular mass. In the Treatment of Mild
Hypertension Study, all the
antihypertensive drugs used resulted in reductions in LVH but the
diuretic caused a significantly greater reduction than other non-
diuretic agents. In the
Systolic Hypertension in the Elderly Study, which primarily used
diuretics, there was a significant reduction in LVH at 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)