Physician accuracy in interpreting potential ST-segment elevation myocardial infarction electrocardiograms.

BACKGROUND

With adoption of telemedicine, physicians are increasingly asked to diagnose ST-segment elevation myocardial infarctions (STEMIs) based on electrocardiograms (ECGs) with minimal associated clinical information. We sought to determine physicians' diagnostic agreement and accuracy when interpreting potential STEMI ECGs.

METHODS AND RESULTS

A cross-sectional survey was performed consisting of 36 deidentified ECGs that had previously resulted in putative STEMI diagnoses. Emergency physicians, cardiologists, and interventional cardiologists participated in the survey. For each ECG, physicians were asked, "based on the ECG above, is there a blocked coronary artery present causing a STEMI?" The reference standard for ascertaining the STEMI diagnosis was subsequent emergent coronary arteriography. Responses were analyzed with generalized estimating equations to account for nested and repeated measures. One hundred twenty-four physicians interpreted a total of 4392 ECGs. Among all physicians, interreader agreement (kappa) for ECG interpretation was 0.33, reflecting poor agreement. The sensitivity to identify "true" STEMIs was 65% (95% CI: 63 to 67) and the specificity was 79% (95% CI: 77 to 81). There was a 6% increase in the odds of accurate ECG interpretation for every 5 years of experience since medical school graduation (OR 1.06, 95% CI: 1.02 to 1.10, P = 0.01). After adjusting for experience, there was no significant difference in the odds of accurate interpretation by specialty-Emergency Medicine (reference), General Cardiology (AOR 0.97, 95% CI: 0.79 to 1.2, P = 0.80), or Interventional Cardiology physicians (AOR 1.24, 95% CI: 0.93 to 1.7, P = 0.15).

CONCLUSIONS

There is significant physician disagreement in interpreting ECGs with features concerning for STEMI. Such ECGs lack the necessary sensitivity and specificity to act as a suitable "stand-alone" diagnostic test.