Abstract 17456: Early Repolarization is Associated With Resuscitated Sudden Cardiac Arrest but not Autopsy-Proven Sudden Arrhythmic Death
Introduction: Association between early repolarization (ER) on ECG and sudden cardiac arrest (SCA) risk has been suggested by epidemiologic studies with variable prognostic results. This association has not been investigated in autopsy-proven sudden cardiac deaths (SCDs).
Methods: All pre-arrest ECGs performed as part of medical care were obtained and reviewed for ER on all resuscitated SCAs and all out-of-hospital (OOH) SCDs in San Francisco (SF) between 2/1/2011 and 3/1/2014 captured through active surveillance of all deaths reported to the Office of the Chief Medical Examiner as part of the SF Postmortem Systematic Investigation of Sudden Cardiac Death (POST SCD) study. All contemporaneous citywide resuscitated SCAs were identified via responding SF Fire Department paramedic records and cause of death was adjudicated after review of autopsy, toxicology, histology, and medical records. ER was defined as elevation of QRS-ST junction ≥ 0.1mV in ≥ 2 contiguous inferior or lateral leads, manifesting as end-QRS slurring or notching. Comparison of ER for autopsy-proven sudden arrhythmic deaths (SADs) was made to: (1) randomly sampled SF trauma deaths, (2) SCAs who survived to hospital admission but died before discharge (SCA-IDs), and (3) SCAs who survived to hospital discharge and received implantable cardioverter-defibrillator (SCA-ICDs).
Results: Autopsy capture rate was 97% of all incident OOH sudden deaths in SF (525/541); 54% (294/541) were SADs. 152 of 567 cases (SADs, SCA-IDs, SCA-ICDs, traumas) had pre-arrest ECGs performed. ER was present in 20% of SADs (18/90), 13% of traumas (4/30), 62% of SCA-IDs (8/13), and 37% of SCA-ICDs (7/19). ER was more prevalent in SCA-IDs than in SADs (p=0.003). Adjusted for age, race, and gender, ER was associated with SCA-ID [OR 13.1; 95%CI 2.3-74.1; p=0.004] and SCA-ICD [OR 7.6; 95%CI 1.3-45.6; p=0.03] but not OOH SADs [OR 1.6; 95%CI 0.5-5.3; p=0.4] compared to traumas as a population reference.
Conclusion: In the autopsy-defined POST SCD study, capturing the vast majority of all OOH SCAs in an entire metropolitan area, we found increased prevalence of ER among SCAs who survived to hospital admission but not SCAs who died OOH, i.e., SADs, as compared to controls. Thus, ER may predict resuscitated SCA but not autopsy-proven SAD.
Author Disclosures: V.A. Narla: None. E. Moffatt: None. P. Ursell: None. R. Khan: None. A. Bedigian: None. J. Olgin: None. Z.H. Tseng: None.
- © 2016 by American Heart Association, Inc.