The effect of nitrates during evolving myocardial infarction is controversial. While previous studies showed that nitrates improve left ventricular function and have a beneficial effect on survival, two recent randomized megatrials showed that nitrates did not alter mortality after acute myocardial infarction (AMI). The present study analyzes the use of nitrates in clinical practice and their impact on mortality in a cohort of unselected consecutive AMI patients admitted to all 25 coronary care units operating in Israel during 2 months in 1994. Among 966 patients in Killip class I-III on admission, 81% (n = 783) received nitrate therapy by intravenous infusion or orally. Baseline characteristics of patients treated with or without nitrates were quite similar. Seven-day mortality was markedly reduced in the nitrate-treated group (5 and 11%, p < 0.001) in comparison with those who did not receive nitrates. After adjustment for pertinent variables the 7-day relative risk (RR) of mortality was 0.51 [95% confidence interval (CI) 0.25-1.07; p = 0.08], whereas, the 7-day to 1-year mortality after AMI was not altered by nitrate use (RR = 0.97; 95% CI 0.56-1.68; p = 0.92). Nitrate therapy remains a widespread and a valid symptom-oriented therapeutic approach, especially early after AMI, in the community.
- Acute myocardial infarction