Labetalol infusion in acute myocardial infarction with systemic hypertension.

1 Fifteen patients with suspected acute myocardial infarction and systemic BP of greater than 160/110 mmHg were treated with an incremental infusion of labetalol. 2 Systemic BPs were safely and effectively lowered to less than 130 mm Hg systolic or 90 mmHg diastolic in all pateints. 3 Heart rate, mean pulmonary artery wedge pressure cardiac index and stroke work index were significantly reduced. 4 The dose of labetalol varied from 30 mg--440 mg and was significantly higher (mean 295 mg) in those patients with pre-existing systemic hypertension compared with others (mean 133 mg). 5 No side-effects occurred and all patients survived to leave hospital.