Abstract 19107: Ventricular Fibrillation Quantitative Electrocardiogram Measures Associated With Return of Organized Rhythm in Out-of-Hospital Cardiac Arrest
Introduction: Out-of-Hospital cardiac arrest (OHCA) is a major cause of mortality, and ventricular fibrillation (VF) is a common electrocardiogram (ECG) presentation of OHCA. Quantitative ECG (QECG) metrics of the VF waveform, including Amplitude Spectrum Area (AMSA), median slope (MS), and centroid frequency (CF), may have utility for guiding defibrillation and CPR. Even so, VF QECG measures have yet to be translated to prehospital care. We sought to use data from a large contemporary resuscitation trial to further understand their utility.
Hypothesis: We hypothesized that QECG metrics would be associated with return of organized rhythm (ROOR) in OHCA.
Methods: Data from prehospital, EMS-treated cardiac arrests from 2011 to 2015, enrolled in the Continuous Chest Compression trial, were used in this study and obtained from 7 ROC sites. Data were downloaded from monitors using manufacturer software. Signal data were then extracted from the downloaded files using a custom Matlab program (Mathworks Inc, Natick, MA). ECG pre-shock segments used for QECG analysis included ECG following the last chest compression before a shock, up to the time immediately before the shock. Return of organized rhythm (ROOR) was defined as a regularly occurring complex, regardless of rate or QRS width, during the largest compression gap in a three-minute period post-shock. AMSA, MS, and CF, were calculated as the mean of all available consecutive 3 second ECG segments that were free of compression artifact. Logistic regression was performed for each QECG measure using an outcome of ROOR, with separate models for total shocks and first shocks. Statistics were performed with STATA (StataCorp LP, College Station, TX).
Results: 3,941 total shocks and 999 first shocks were found in 1842 unique OHCA cases. ROOR rate for all shocks was 25.7% and ROOR rate per case was 40.28%. QECG odds ratios for ROOR in total shocks were AMSA 1.07 (1.05-1.09) p <.001, MS 1.48 (1.33-1.1.65) p<001, CF 7.89 (.75-8.78) p = .130). QECG odds ratios for ROOR from first shock were were AMSA 1.06 (1.03-1.09) p <.001, MS 1.37 (1.18-1.58) p <.001, CF 4.52 (.728-28.01) p = .105.
Conclusions: In this large cohort of EMS-treated OHCA patients with a recorded shock, AMSA and MS were significantly associated with ROOR.
Author Disclosures: M.L. Sundermann: Other; Modest; Co-Inventor of a patent pending titled: “Automatic Chest Compression Systems That Incorporates Biological Feedback,” PCT/US2014/071544. D.D. Salcido: Other; Modest; Co-Inventor of a patent pending titled: “Automatic Chest Compression Systems That Incorporates Biological Feedback,” PCT/US2014/071544. A.C. Koller: None. K. Flickinger: None. J.J. Menegazzi: Other; Modest; Co-Inventor of a patent pending titled: “Automatic Chest Compression Systems That Incorporates Biological Feedback,” PCT/US2014/071544.
- © 2016 by American Heart Association, Inc.