[Effects of cimetidine on the cardiovascular system of normal subjects].

The effect of cimetidine on the cardiovascular system of normal subjects has been assessed. Eight healthy subjects were submitted to i.v. infusion on 200 mg of cimetidine in 2'; at a second stage, five of these were treated with placebo in equal volume and infusion speed. Polygraphic (LVET, PEP, PEP/LVET, triple product) and echocardiographic (systolic volume, cardiac capacity, velocity, circumferential shortening and ejection fraction) parameters were considered and heart frequency and arterial pressure measured. Measurements were carried out prior to infusion and for periods subsequent to the end of infusion. The results showed a statistically significant reduction only in heart frequency, triple product and cardiac output of subjects treated with cimetidine; no modifications were observed in subjects treated with placebo. It is concluded that cimetidine changes in heart frequency and its related parameters.