ST-segment elevation in aVR following return of spontaneous circulation is associated with worse outcomes in cardiac arrest

Abstract

Abstract Funding Acknowledgements Type of funding sources: Private hospital(s). Main funding source(s): Boston Medical Center Background ST-segment elevation in lead aVR (STE-aVR) is suggestive of global myocardial ischemia, typically in the setting of left main disease, triple vessel disease, or severe metabolic derangements, and is associated with increased mortality in acute coronary syndrome. The prevalence and prognostic significance of STE-aVR in patients presenting with cardiac arrest has not been previously described. Purpose We sought to describe the prevalence of STE-aVR among comatose survivors of cardiac arrest and evaluate the association of STE-aVR with in-hospital mortality and favorable neurologic outcome at hospital discharge. Methods We conducted a retrospective analysis of patients enrolled in the Multimodal Outcome CHAracterization in cardiac arrest patients (MOCHA) study at a single academic center. Participants were comatose survivors of cardiac arrest aged 18-89 years who had an initial electrocardiogram (ECG) obtained after ROSC between 2011-2020. STE-aVR was defined as ST elevation at the J point of ≥1 mm as measured by two trained assessors. Outcomes included in-hospital mortality and favorable neurologic outcome at hospital discharge (Cerebral Performance Category 1-2). Multivariable logistic regression, adjusted for age, medical comorbidities (diabetes, chronic kidney disease, heart failure, malignancy) and arrest characteristics (location, initial rhythm, witnessed status, bystander CPR) was used to test the association between outcomes and STE-aVR on ECG. Results 471 (89.0%) patients met inclusion criteria and were included in this analysis; 58 (11.0%) were excluded due to missing post-ROSC ECG. The median age was 62 years (Interquartile range: 51-73 years), and 284 (60.4%) were male. 297 (63.2%) presented with out-of-hospital cardiac arrest and 138 (29.4%) presented with a shockable rhythm. STE-aVR was present in 87 patients (18.5%). STE-aVR was more common in patients presenting with out-of-hospital cardiac arrest (22.9% vs 11.0%, P<0.01) but did not differ by initial rhythm (21.8% vs 31.1%, P=0.09). Patients with STE-aVR had higher mortality (83.9% vs 66.1%, P<0.01), which persisted after adjustment for confounding variables (Odds ratio (OR) 2.36; 95% Confidence Interval (CI): 1.23-4.52, P<0.01). Patients with STE-aVR had lower incidence of favorable neurologic outcome (13.8% vs 26.1%, P=0.01), however this association was not significant after adjusting for covariates (OR 0.52; 95% CI:0.26-1.05, P=0.07). Conclusion STE-aVR was present in nearly 1 in 5 comatose survivors of cardiac arrest. STE-aVR was independently associated with in-hospital mortality. Further research is needed to clarify the clinical significance and mechanism of STE-aVR in patients presenting with cardiac arrest.