Association of amplitude spectral area of the ventricular fibrillation waveform with survival of out-of-hospital ventricular fibrillation cardiac arrest

Julia H Indik; Zacherie Conover; Meghan McGovern; Annemarie E Silver; Daniel W Spaite; Bentley J Bobrow; Karl B Kern

doi:10.1016/j.jacc.2014.06.1196

Association of amplitude spectral area of the ventricular fibrillation waveform with survival of out-of-hospital ventricular fibrillation cardiac arrest

J Am Coll Cardiol. 2014 Sep 30;64(13):1362-9. doi: 10.1016/j.jacc.2014.06.1196.

Authors

Julia H Indik¹, Zacherie Conover², Meghan McGovern², Annemarie E Silver³, Daniel W Spaite⁴, Bentley J Bobrow⁵, Karl B Kern²

Affiliations

¹ Sarver Heart Center, University of Arizona College of Medicine, Tucson, Arizona. Electronic address: jindik@email.arizona.edu.
² Sarver Heart Center, University of Arizona College of Medicine, Tucson, Arizona.
³ ZOLL Medical, Chelmsford, Massachusetts.
⁴ Department of Emergency Medicine, University of Arizona College of Medicine, Tucson, Arizona.
⁵ Department of Emergency Medicine, Maricopa Medical Center, University of Arizona College of Medicine, Phoenix, Arizona.

PMID: 25257639
DOI: 10.1016/j.jacc.2014.06.1196

Abstract

Background: Previous investigations of out-of-hospital cardiac arrest (OHCA) have shown that the waveform characteristic amplitude spectral area (AMSA) can predict successful defibrillation and return of spontaneous circulation (ROSC) but has not been studied previously for survival.

Objectives: To determine whether AMSA computed from the ventricular fibrillation (VF) waveform is associated with pre-hospital ROSC, hospital admission, and hospital discharge.

Methods: Adults with witnessed OHCA and an initial rhythm of VF from an Utstein style database were studied. AMSA was measured prior to each shock and averaged for each subject (AMSA-avg). Factors such as age, sex, number of shocks, time from dispatch to monitor/defibrillator application, first shock AMSA, and AMSA-avg that could predict pre-hospital ROSC, hospital admission, and hospital discharge were analyzed by logistic regression.

Results: Eighty-nine subjects (mean age 62 ± 15 years) with a total of 286 shocks were analyzed. AMSA-avg was associated with pre-hospital ROSC (p = 0.003); a threshold of 20.9 mV-Hz had a 95% sensitivity and a 43.4% specificity. Additionally, AMSA-avg was associated with hospital admission (p < 0.001); a threshold of 21 mV-Hz had a 95% sensitivity and a 54% specificity and with hospital discharge (p < 0.001); a threshold of 25.6 mV-Hz had a 95% sensitivity and a 53% specificity. First-shock AMSA was also predictive of pre-hospital ROSC, hospital admission, and discharge. Time from dispatch to monitor/defibrillator application was associated with hospital admission (p = 0.034) but not pre-hospital ROSC or hospital discharge.

Conclusions: AMSA is highly associated with pre-hospital ROSC, survival to hospital admission, and hospital discharge in witnessed VF OHCA. Future studies are needed to determine whether AMSA computed during resuscitation can identify patients for whom continuing current resuscitation efforts would likely be futile.

Keywords: cardiopulmonary resuscitation; heart arrest; ventricular fibrillation.

Publication types

Multicenter Study
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Area Under Curve
Arizona
Cardiopulmonary Resuscitation
Databases, Factual
Defibrillators
Electric Countershock
Female
Humans
Logistic Models
Male
Middle Aged
Out-of-Hospital Cardiac Arrest / physiopathology*
Patient Admission
Patient Discharge
Retrospective Studies
Sensitivity and Specificity
Ventricular Fibrillation / physiopathology*