Abstract 14658: Do the New ECG Criteria for ST Elevation MI (STEMI) Result in Too Many Low Risk Patients Being Considered for Coronary Reperfusion Therapy?
Background: The Universal Definition of Myocardial Infarction (UDMI) requires complicated ECG criteria for ST elevation MI (STEMI) with differing amplitudes (0.1, 0.15, 0.2 and 0.25mV) for age and gender but not ethnicity. Since these criteria are based primarily on expert opinion, we sought to explore the possibility they yield a high number of false positives. Such misclassification could initiate in hospitalization and STEMI treatment for an unnecessary number of patients presenting with non-cardiac chest pain.
Methods: We evaluated computerized measurements of ST segment amplitude from the resting ECGs of 45,828 patients at the Palo Alto Veterans’ Affairs Hospital. The average age was 56 (±15) years, with 90% male, 12% African-American, and 74% outpatients. There were 3,929 (9.0%) cardiac deaths over a mean follow-up of 7.6 (± 3.8) years. Further analysis was also completed in the ambulatory subpopulation (n = 28451).
Results: Within the general clinical population, 4.2% (1963/45828) of cases met the prescribed ST elevation criteria. Analysis with respect to gender, age and ethnicity demonstrated that among males under the age of 40 years, 17% (175/985) of African Americans and 6.6% (240/3651) of non-African Americans met the criteria. For males above the age of 40 years, the criteria were fulfilled in 8% (320/3939) of African Americans and 3.4% (1079/31419) of non-African Americans. Only 1.7% (78/4571) of women met the criteria with higher percentages among African American women (2.2%). In the ambulatory subpopulation, who exhibited a lower CV mortality (less than 1%/year), there were similar but slightly lower percentages.
Conclusion: Except for women, the criteria for ischemic ST segment elevation are too often fulfilled in ambulatory, low risk Veterans Affairs patients, particularly African Americans. This is unlikely to reflect the actual prevalence of cardiac ischemia within these populations and implies that the utilization of the criteria in isolation may lead to an over-diagnosis of acute myocardial ischemia, unnecessary cardiac interventions, and a delay in appropriate care. We have documented that ECG criterion for STEMI should be adjusted for men under 40, particularly African Americans.
- © 2013 by American Heart Association, Inc.