Does intravenous phentolamine improve hemodynamic parameters in patients with acute myocardial infarction associated with hypertension?
Intravenous phentolamine improves hemodynamics by reducing left ventricular filling pressure and increasing cardiac index in patients with acute myocardial infarction and hypertension.
In 11 patients with hypertension associated with acute myocardial infarction intravenous phentolamine decreased the elevated left ventricular filling pressure. Cardiac index increased with a small decrease in arterial pressure, and therefore the same or increased stroke work was achieved at a lower filling pressure. In patients with acute hypertension myocardial oxygen demand was decreased and this may tend to increase infarct size. The potentially beneficial effects were less great in patients with chronic hypertension antedating the myocardial infarction.
Kelly et al. (Sun,) studied this question.