Dose-related haemodynamic effects of nicardipine during rest and exercise and variable anti-anginal effects in patients with chronic stable angina.

Abstract

The effects of increasing doses of i.v. nicardipine (2.5, 5.0 and 7.5 or 10.0 mg) on blood pressure, heart rate and exercise performance were studied in 12 patients with chronic effort angina. Plasma nicardipine concentrations correlated closely with the infused doses (r = 0.90). Resting haemodynamic changes after nicardipine included a dose-related fall in systolic (5%, 13%, 15%) and diastolic (0%, 6%, 8%) blood pressure and a rise in heart rate (10%, 19%, 30%). Rate-pressure product was slightly increased after the highest dose (10%). During exercise, maximal systolic blood pressure decreased (3%, 9%, 9%) and heart rate increased (2%, 4%, 9%) but the rate-pressure product remained unchanged. Exercise tolerance improved in 10 patients as indicated by prolonged exercise duration in all, delayed appearance of ST-segment depression in 6, decreased maximal ST-segment depression in 5, and abolished (N = 3) or diminished (N = 4) anginal pain at the end of exercise after optimal nicardipine dose. Five of the 10 patients obtained maximum benefit after the highest dose. The other five patients improved after 2.5 or 5.0 mg but deteriorated (N = 4) or had no further benefit when the dose was increased (N = 1). One patient deteriorated even after the lowest dose, whereas one patient neither improved nor deteriorated after any dose. The patients who deteriorated after low or high doses tended to be more severely diseased than those who tolerated the maximal dose well. The results stress the importance of individual dose titration of nicardipine to ensure maximum benefit in patients with chronic effort angina.