Effect of nisoldipine upon the general and coronary hemodynamics of the anesthetized dog.

The effect of nisoldipine (5 micrograms/kg/i.v.) was studied in anesthetized intact dogs. This calcium antagonist increased heart rate by 68%, doubled cardiac output, and increased coronary sinus flow from 62 +/- 10 ml/min to a maximum of 131 +/- 7 ml/min. Mean systemic pressure decreased from 125 +/- 10 mm Hg to a minimum of 115 +/- 2 mm Hg for at least 15 min after the injection. Mean pulmonary artery pressure increased from 12 +/- 2 mm Hg to 18 +/- 4 mm Hg within 2 min of the injection. Left ventricular work (joules/s) doubled and right ventricular work trebled during the first 15 min after injection. Peripheral resistance fell by 57%, total pulmonary resistance by 40%, and coronary vascular resistance by half. Coronary sinus O2 content increased by 50%, and cardiac efficiency (index) increased from 0.2 (control) to a maximum of 0.46, within 2 min after the injection of the drug.