Prevalence and Prognostic Impact of ST Segment Elevation in Lead aVR Among Patients with Cardiac Arrest

Abstract Background In acute coronary syndrome, ST-segment elevation in lead aVR (STE-aVR) indicates global myocardial ischemia, often related to multivessel or severe left main disease, and correlates with increased mortality. The prevalence and prognostic significance of STE-aVR in cardiac arrest (CA) patients is unknown. Methods We identified patients (≥18 years) with CA between 2011 to 2022 who achieved return of spontaneous circulation (ROSC). The first electrocardiogram (ECG) post-ROSC was assessed for STE-aVR, defined as ≥1 mm ST-segment elevation at the J point, measured by two trained assessors. Multivariable logistic regression was used to analyze the association between STE-aVR and outcomes (in-hospital mortality and poor neurologic outcome), adjusted for patient and arrest characteristics. Results Including 443 CA patients, the median (IQR) age was 61 years (50-72 years), with 60.5% (n=268) male, 65.7% (n=291) presenting with out-of-hospital cardiac arrest (OHCA) and 29.8% (n=132) with shockable rhythms. STE-aVR was observed in 18.3% (n=81) of patients. Those with STE-aVR were more likely to present with OHCA and less likely to have a shockable rhythm (both, P<0.05). STE-aVR was associated with higher in-hospital mortality (86.4% vs 65.8%, P<0.001) and poor neurologic outcomes (90.1% vs 72.9%, P=0.001). After multivariable adjustment, STE-aVR remained associated with higher in-hospital mortality (odds ratio [OR] 2.23; 95% confidence interval [CI]: 1.02-4.84, P=0.04), but not a poor neurologic outcome (OR 2.12; 95% CI: 0.90-4.98, P=0.09). Conclusions STE-aVR was present in 1 in 5 CA survivors and was independently associated with higher in-hospital mortality.