Risk of Acute Myocardial Infarction in Cocaine Abusers
To the Editor:
I read with interest but some skepticism the article on the triggering of myocardial infarction by cocaine by Mittleman et al.1 They reported that in the first hour after cocaine use, the risk of acute myocardial infarction was 23.7 times greater than the baseline risk (95% confidence interval, 8.5 to 66.3) during periods of nonexposure to cocaine.
Unfortunately, this study was retrospective and included only admitted patients, as was a similar study reported by Amin et al,2 which had an incidence of cocaine-associated myocardial infarction as high as 31%. Three recent prospective studies that included patients who were discharged from the emergency departments of the hospitals found a much lower incidence, ranging from 2.5% to 8.7%,3 with an approximate average of 6%.4 5
The low frequency of myocardial infarction reported by such prospective studies is in contrast to the high frequency reported by retrospective studies and has obvious clinical implications. Observation units in the emergency departments may offer an alternative to routine hospital admissions to coronary care units for evaluating patients with cocaine-associated chest pains, with or without abnormal electrocardiograms. Such a cost-saving approach will have a significant financial impact in the current environment of managed care, because chest pain is the most common cocaine-related symptom among patients presenting to the emergency department.
- Copyright © 2000 by American Heart Association