Abstract 12595: Fragmented QRS With Benign Early Repolarization Pattern is a Strong Predictor of Adverse Events in Patients With Suspected Acute Coronary Syndrome

Abstract

Introduction: Early repolarization pattern (ERP) and fragmented QRS (fQRS) are well studied ECG markers of risk in various clinical populations. Emerging evidence suggests that coexistence of these patterns constitutes a synergistic substrate for arrhythmogenic events. Examining the prognostic value of these patterns would have immediate clinical applications for the triage of high-risk patients, including those with suspected acute coronary syndrome (ACS). Methods: This was a prospective study that enrolled chest pain patients transported via ambulance to UPMC hospitals. ERP was manually over-read by a blinded physician according to published guidelines. fQRS was automatically calculated as QRS loop notching on 3-D vectorcardiogram using manufacturer software. Patients were classified to four groups: 1) no ERP or fQRS; 2) ERP only; 3) fQRS only; and 4) both fQRS/ERP. Study outcome was major adverse cardiac events (MACE) within 30 days of admission, defined as: ACS, death, coronary revascularization, cardiac arrest, ventricular dysrhythmia, cardiogenic shock, and acute heart failure. Two independent reviewers adjudicated outcomes from the charts. Results: After excluding those with wide QRS (>110ms), this analysis included 1392 out of 1650 patients on whom ECG interpretation was available (Age 57 ± 16; 48% females, 41% Black, 20% with adjudicated 30-day MACE). The prevalence of patients with no ERP/fQRS, ERP-only, fQRS-only, and both fQRS/ERP were 13%, 22%, 24%, and 41% respectively. In univariate analysis, those with fQRS-only (OR: 1.74; [95% CI, 1.03-2.94], p=0.038), and fQRS/ERP (OR: 2.14; [95% CI, 1.32-3.48], p=0.002) were associated with MACE compared to no ERP or fQRS as reference group. In final multivariate model, controlling for demographic and clinical data, fQRS/ERP remained a strong predictor of MACE (OR: 2.27; [95% CI, 1.34-3.87], p=0.002). Conclusions: Coexistence of fQRS/ERP on presenting ECG provides a strong predictor for 30-day MACE in suspected ACS, independent of patient characteristics These qualitative patterns can be easily visualized by clinicians during ECG interpretation, enhancing their potential application. The incremental role of these patterns in established tools (e.g., TIMI) is yet to be determined.