A preliminary double-blind study of intravenous nitroglycerin in acute myocardial infarction.

A preliminary double-blind, placebo-controlled study of the effects of a 48-h intravenous infusion of nitroglycerin (NG) in 140 patients with acute myocardial infarction has been carried out. The patients were randomised to placebo or active treatment within 12 h of the onset of symptoms. Those patients treated with nitroglycerin showed a significant reduction on both days in systolic blood pressure, haemoglobin concentration, and packed cell volume. There was also a significant reduction in diamorphine usage in the first 24 h. There was a higher incidence (non-significant) of dysrhythmia in the placebo group despite an increased usage of antidysrhythmic therapy. The mortality rate in the placebo group was 13%, and 7.8% in the active treatment group, but this difference was not significant. At the 3-month follow-up, 83% of treated patients as opposed to 60% of placebo group were able to resume normal or near-normal activities. Preliminary findings suggest that intravenous NG may be useful treatment for patients with acute myocardial infarction and a larger-scale trial is warranted.