Effects of sublingual nifedipine on hemodynamics and systolic and diastolic function in patients with hypertrophic cardiomyopathy

Abstract

The hemodynamic effects of sublingual nifedipine were examined in 36 patients with hypertrophic cardiomyopathy. Twenty-one patients were initially given 20 mg and 15 patients were given 10 mg of the drug; 30 min after this first dose 26 patients received 10 mg and one patient 20 mg as a second dose. Hemodynamic findings in patients who received different doses of the drug were similar. Peak effects included an increase in heart rate from 79 ± 12 to 91 ± 14 (mean ± 1 SD) beats/min (p < .01) and a decrease in mean blood pressure from 89 ± 12 to 77 ± 10 mm Hg (p < .01). Overall, left ventricular outflow tract gradient (LVOTG) did not change in patients with significant (≥30 mm Hg) basal LVOTG (75 ± 22 to 83 ± 22 mm Hg; NS), but it increased significantly in those six patients in whom peripheral vascular resistance fell by 25% or more (73 ± 28 to 99 ± 22 mm Hg; p < .05). Pulmonary arterial wedge pressure increased significantly in patients with normal (≤15 mm Hg) basal values (9 ± 3 to 14 ± 7 mm Hg; p < .01) and in patients with significant basal LVOTG (15 ± 8 to 20 ± 10 mm Hg; p