Abstract 17787: The Majority of Underlying Causes of PEA and Asystole Sudden Deaths Are Non-Cardiac by Systematic Autopsy Investigation
Background: The incidence of ventricular tachycardia/fibrillation (VT/VF) as the presenting rhythm in witnessed sudden cardiac deaths (SCDs) has been declining, with increasing incidence of pulseless electrical activity (PEA), asystole, and other/agonal rhythms. However, due to low prevailing autopsy rates of SCDs, the actual underlying cause of death (COD) in non-VT/VF SCDs is unknown.
Methods: In the first 20 months of the Comprehensive UCSF SCD Study (02/1/2011-9/30/2012), systematic autopsies were performed on 241 of 261 (92.3%) of all incident WHO SCDs captured through active surveillance of all deaths reported to the San Francisco Medical Examiner’s Office. Evaluation for all cases included full autopsy, toxicology, histology, and detailed examination of the heart and cranial vault. A multidisciplinary committee reviewed prehospital, medical records and autopsy results to adjudicate a final COD by consensus. Arrhythmic CODs required the absence of fatal non-cardiac (e.g, pulmonary embolism, lethal toxicology) or non-arrhythmic (e,g., tamponade) autopsy findings.
Results: Of 241 incident WHO SCDs, 70 (29.2%) experienced a witnessed arrest. Of these, 23 (32.8%) presented in asystole, 29 (41.4%) in VT/VF, 11 (15.7%) in PEA, 3 (4.3%) in agonal/idioventricular, and 4 (5.8%) in other. Arrhythmic COD was found in 27/29 (93.1%) VT/VF subjects, significantly higher than asystole (13/23, 56.5%, p=0.019), PEA (4/11, 36.4%, p=0.018), agonal/idioventricular (1/3, 33.3%, p<0.001), and other (1/4, 25%, p<0.001). Non-cardiac COD were rare in VT/VF subjects (2/29, 6.9%) but common in asystole (10/23, 43.5%, p=0.002), PEA (7/11, 63.6%, p<0.001) and other (3/4, 75%, p<0.001). The most common non-arrhythmic COD were overdose (5/16), PE (4/16), and aortic dissection (3/16). We found no significant demographic differences between subjects presenting in VT/VF and non-VT/VF rhythms.
Conclusions: Although non-VT/VF rhythms at SCD presentation are increasingly common, the majority of underlying causes of these sudden deaths are non-cardiac by systematic autopsy investigation. Further investigation is needed to better elucidate the mechanisms and develop resuscitation strategies to better treat these non-cardiac sudden deaths.
- © 2013 by American Heart Association, Inc.