Comparison of haemodynamic effects of phentolamine, sodium nitroprusside, and glyceryl trinitrate in acute myocardial infarction.

Abstract

The effects of the commonly employed systemic vasodilators phentolamine, nitroprusside, and intravenous glyceryl trinitrate on cardiac performance, peripheral resistance, and vascular capacitance, as judged by changes in left ventricular filling pressure, were compared in 29 patients studied within 24 hours after the onset of acute myocardial infarction. To provide a common basis for comparison the mean arterial pressure was lowered to the same level of about 80 mmHg in the previously normotensive patients and 90 to 100 mmHg in the patients with a history of hypertension, respectively. To provide a direct comparison in the same patients, of 20 patients treated with nitroprusside, 12 were also treated with nitroglycerin; 8 patients were given nitroprusside as well as phentolamine.