Hemodynamic assessment of nicardipine alone and with atenolol in coronary artery disease using a modified echo-doppler device

Abstract

We have used a modified noninvasive echo-Doppler cardiac output device, based on the principle of attenuated compensation volume flow, to assess the cardiovascular effects of the slow-calcium antagonist nicardipine in coronary disease. The dose-response effects of 2.5, 5.0 and 10.0 mg intravenous nicardipine were determined in 8 patients with angina. Dose-related decreases were seen in systemic mean arterial pressure (p <0.01) after administration of nicardipine. Cardiac pumping indexes were improved, as evident from linear increases in cardiac stroke volume (p <0.01), stroke length (p <0.01) and time-averaged mean velocity (p <0.01). The echo-Doppler device was also used to assess β-blocking/nicardipine combination therapy in patients with angina. When nicardipine was given after the cardioselective β blocker atenolol the reduction in heart rate and cardiac output after atenolol was reversed compared with a group that received atenolol followed by placebo. Cardiac performance improved and the 35% reduction in systemic vascular resistance was associated with markedly increased cardiac index (p <0.01), augmentation of time-averaged mean velocity (p <0.01) and cardiac stroke length (p <0.05). These data are consistent with previous invasive studies of nicardipine, either alone or when combined with β blockade in coronary disease. The data also suggest that nicardipine/β-blocking combination is safe in patients with coronary heart disease and that the echo-Doppler method of cardiovascular monitoring will prove useful in human pharmacodynamic studies.