Apr 6, 2011

Myocardial substrate in secondary ventricular fibrillation: insights from quantitative waveform measures

Prehospital Emergency Care : Official Journal of the National Association of EMS Physicians and the National Association of State EMS Directors
Matthew HallThomas D Rea


Some patients presenting with nonshockable cardiac arrest rhythms will subsequently manifest ventricular fibrillation. Their prognosis remains poor despite transition to a shockable rhythm. Quantitative waveform measures assess the electrophysiologic status of the fibrillating heart and predict outcome. To use waveform measures to compare those who presented initially with ventricular fibrillation (primary group) with those who manifested ventricular fibrillation after initially presenting with a nonshockable arrest rhythm (secondary group). We conducted an observational study using a convenience sample to compare waveform measures of amplitude spectrum area (AMSA), cardioversion output predictor (COP), and detrended fluctuation analysis (DFA) prior to initial shock between the primary (n = 178) and secondary (n = 28) groups. We produced a primary group matched to the secondary group based on the average waveform values to evaluate the observed versus expected outcomes in the secondary group. Survival was 42% in the primary group and 0% in the secondary group. There was a trend toward more favorable waveform values in the primary compared with the secondary group (9.48 versus 9.29, p = 0.10 for AMSA; 13.75 versus 14.12, p = 0.0...Continue Reading

  • References7
  • Citations1


  • References7
  • Citations1


Mentioned in this Paper

Ventricular Fibrillation
Observation - Diagnostic Procedure
Nested Case-Control Studies
Electroversion Therapy
Electrocardiographic Recorders

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