EFFECT OF ORAL H-2-RECEPTOR ANTAGONISTS ON LEFT-VENTRICULAR SYSTOLIC FUNCTION AND EXERCISE CAPACITY IN PATIENTS WITH CHRONIC STABLE HEART-FAILURE

Study Objective. To evaluate the effect of cimetidine, famotidine, ran itidine, and placebo on left ventricular systolic function, aerobic me tabolic performance, and exercise capacity in patients with chronic, s table heart failure. Design. Double-blind, randomized, placebo-control led, four-way crossover study. Setting. Outpatient, university-affilia ted cardiology clinic. Patients. Twelve men with stable New York Heart Association class II or III heart failure secondary to ischemic heart disease or hypertension. Interventions. Patients received in random s equence cimetidine 400 mg twice/day, famotidine 40 mg/day, ranitidine 150 mg twice/day, and placebo. Each treatment was administered for 7 d ays, and the periods were separated by a 1-week washout. Measurements and Main Results. Before and after each treatment, patients underwent a bicycle stress echocardiogram with aerobic metabolic assessment. Lef t ventricular function was evaluated by calculating ejection phase ind exes from Doppler echocardiographic measurements. All 12 patients succ essfully completed the study. No patient reported any adverse effect a ttributed to study drugs. None of the treatments was associated with s ignificant changes in any measure of left ventricular systolic functio n, aerobic metabolic performance, or exercise capacity, nor were place bo-subtracted differences for the agents significantly different for a ny of the three measures. Conclusion. The three H-2-receptor antagonis ts administered for 7 days at. clinical dosages have no significant ef fect on left ventricular systolic function, aerobic metabolic performa nce, or exercise capacity in men with class II or III stable heart fai lure.