Although it is known that reperfusion therapy for ST-elevation myocardial infarction (STEMI) is underused, the reasons for the failure to provide this potentially life-saving treatment are not well described.

In a cohort of 2215 consecutive patients presenting with acute myocardial infarction to 5 emergency departments in Colorado and California between 2000 and 2002, patients with ischemic symptoms and ST-segment elevation on electrocardiogram without documented guideline-based contraindications to therapy were identified as eligible reperfusion candidates. Multivariable logistic models were constructed to identify factors associated with the failure to receive reperfusion. The emergency department records of patients not receiving reperfusion were reviewed to categorize the reasons therapy was not provided.

Of 460 eligible patients, 102 (22%) did not receive reperfusion therapy. Patient factors associated with failure to receive reperfusion therapy included older age, peripheral vascular disease, and absence of chest pain; patients seen by both resident and attending physicians were more likely to receive treatment than those seen by an attending alone. In cases where reperfusion was not provided, ST-segment elevation was not identified in 34% (n = 35), left bundle-branch block was not considered as an indication in 13% (n = 13), there was documentation of a reason for withholding therapy not supported by guidelines in 34% (n = 35), and there was no documentation of reasons for withholding reperfusion in 19% (n = 19).

Initiatives to improve electrocardiogram interpretation and evidence-based patient selection may reduce gaps in the delivery of reperfusion therapy to eligible candidates and thereby potentially improve STEMI outcomes.