Prospective validation of current quantitative electrocardiographic criteria for ST-elevation myocardial infarction

BACKGROUND: Rapid and reliable diagnosis of ST-elevation myocardial infarction (STEMI) as a surrogate for acute coronary occlusion is critical for early reperfusion therapy.

OBJECTIVES: We aimed to examine the diagnostic performance of current guideline-recommended Electrocardiogram (ECG) STEMI criteria.

METHODS: In a prospective diagnostic multicenter study, we objectively quantified the extent of ST-segment elevation in all ECG leads using an automated software-based analysis of the digital 12-lead-ECG in adult patients presenting to the emergency department (ED) with suspected myocardial infarction (MI). Classification according to current guideline-recommended ECG criteria for STEMI at ED presentation was compared against a final diagnosis adjudicated by two independent cardiologists after reviewing all available medical records including serial ECGs, cardiac imaging and coronary angiograms.

RESULTS: Among 2486 patients, 52 (2%) were found to have significant ST-segment elevation on ECG at ED presentation according to current guideline-recommended ECG criteria for STEMI. Eighty-one (3%) patients received a final adjudicated diagnosis of STEMI. Only 35% (28 of 81) of all patients with a final diagnosis of STEMI were correctly identified (PPV 54% (95% CI 41-66%), sensitivity 35% (95% Cl 24-46%), NPV 97.8% (95% CI 97.5-98.1%). Four reasons for missing STEMIs emerged: timing (significant STE at an earlier/later time point) in 25%, incorrect measurement points in 30%, non or borderline-significant STE in 36% and inferoposterior MI localisation in 9%.

CONCLUSIONS: A computerized analysis of current guideline-recommended ECG criteria for STEMI showed suboptimal diagnostic performance when applied to a single 12‑lead ECG performed at ED presentation.

CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00470587.