Early Repolarization Pattern in Post-Resuscitation ECG and Outcomes in Cardiac Arrest Survivors: A Propensity Score Matching Analysis.

Abstract

Background: Early repolarization patterns (ERP) are a known risk factor for sudden cardiac death; however, their prognostic significance in cardiac arrest survivors remains unclear. This study aimed to investigate the clinical characteristics and outcomes of ERP in post-cardiac arrest survivors.

Methods: This observational cohort study included adult out-of-hospital cardiac arrest survivors (aged ≥18 years) who underwent targeted temperature management at two South Korean tertiary care centers between February 2018 and May 2023. Clinical, ECG, and outcome characteristics were compared between patients with and without ERP. Propensity score matching (PSM) was used to minimize confounding, followed by logistic regression analysis. The primary outcome was survival until the hospital discharge.

Results: Among the 693 post-resuscitation patients, 127 (18.3%) had ERP. The ERP cohort was characterized by a younger average age (59.0 years vs. 64.1 years) and had lower peak levels of troponin I (1.7 vs. 4.5) and creatinine (1.2 vs. 1.4). Multivariable logistic regression analysis revealed that the ERP pattern independently predicted decreased mortality at discharge (Odds Ratio: 1.68; 95% Confidence Interval: 1.04-2.72; p=0.034) after adjusting for potential confounders. However, the difference in achieving favorable neurological outcomes was not statistically significant. These results were consistent within the matched cohort. After matching, groups showed no significant differences in post-resuscitation care variables or adverse events, except for maximum vasopressor doses.

Conclusions: The presence of ERP in post-resuscitation ECG was associated with a greater likelihood of survival until hospital discharge.