Abstract 16266: Lifetime Clinical History of Syncope is Associated with Future Pulseless Electrical Activity vs. Ventricular Fibrillation
Introduction: There has been a significant and unexplained rise in prevalence of sudden cardiac arrest (SCA) cases presenting as pulseless electrical activity (PEA), with corresponding decrease in ventricular fibrillation (VF) rates. Given significantly lower survival from PEA vs. VF, we comprehensively investigated PEA determinants by incorporating first responder data with lifetime clinical history information.
Hypothesis: We hypothesized that subjects manifesting with PEA have distinctive lifetime clinical characteristics from VF.
Methods: In the Northwest US (population approximately one million), cases of out of hospital SCA that underwent attempted resuscitation were identified prospectively (2002 – 2007). Those presenting with PEA vs. VF were compared using chi-square tests and t- tests, as well as logistic regression.
Results: A total of 1277cases age ≥18 years underwent resuscitation by first responders (mean age 65 ± 16 years, 67% male). Presenting arrhythmia was VF in 48%, PEA in 25% and asystole/other in the remainder. Compared to VF cases, PEA cases were older (mean age 68 vs. 63 yrs, p<0.0001), more likely to be female (37% vs. 26%, p=0.0008), and less likely to survive to hospital discharge (6% vs. 25%, p≤0.0001). A history of syncope was a significant predictor of PEA (OR 2.2, CI 1.1–4.5) after adjusting for age, gender, overall disease burden, response time and arrest circumstances. Pulmonary disease was also a significant predictor, but only in men (p for interaction = 0.02). In a subgroup analysis of resting electrocardiograms (n=166), there were no differences in clinical history or prevalence of cardiac conduction system disease (PEA 33% vs. VF 41%, p=0.28).
Conclusions: PEA cases had a significantly higher prevalence of syncope in their lifetime, with other predictors that were distinct from VF cases. Potential mechanistic links between reflex syncope and future manifestation with PEA warrant further exploration.
- © 2010 by American Heart Association, Inc.