Patients with electrocardiographic (ECG) left ventricular hypertrophy (LVH) have repolarization abnormalities of the ST segment that may be confused with an ischemic current of injury. We analyzed the ACTIVATE-SF database, a registry of consecutive emergency department ST-segment elevation (STE) myocardial infarction diagnoses from 2 medical centers. Univariate analysis was performed to identify ECG variables associated with presence of an angiographic culprit lesion. Recursive partitioning was then applied to identify a clinical decision-making rule that maximizes sensitivity and specificity for presence of an angiographic culprit lesion. Seventy-nine patients with ECG LVH underwent emergency cardiac catheterization for primary angioplasty. Patients with a culprit lesion had greater magnitude of STE (3.0 ± 1.8 vs 1.9 ± 1.0 mm, p = 0.005), more leads with STE (3.1 ± 1.6 vs 2.0 ± 1.8 leads, p = 0.002), and a greater ratio of STE to R-S-wave magnitude (median 25% vs 9.2%, p = 0.003). Univariate application of ECG criteria had limited sensitivity and a high false-positive rate for identifying patients with an angiographic culprit lesion. In patients with anterior territory STE, using a ratio of ST segment to R-S-wave magnitude <25% as a diagnostic criteria for STE myocardial infarction significantly improved specificity for an angiographic culprit lesion without decreasing sensitivity (c-statistic 0.82), with a net reclassification improvement of 37%. In conclusion, application of an ST segment to R-S-wave magnitude <25% rule may augment current criteria for determining which patients with ECG LVH should undergo primary angioplasty.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine