Stewart JA. The prohibition on shocking apparent asystole: a history and critique of the argument.
Am J Emerg Med. 2008 ;26(5):618-22.
However, it is an idea/question that I did not raise in that article. Asystole changing to ventricular fibrillation (VF) is occasionally documented in the literature (Example: Meaney PA. Rhythms and outcomes of adult in-hospital cardiac arrest. Crit Care Med. 2010; 38(1): 101-8)), but I have never seen a hypothesis for the mechanism of such a metamorphosis. I am no cardiologist, much less an electrophysiologist, but my limited understanding of cardiac electrophysiology makes me wonder how electrical silence could spontaneously morph into frenetic (disorganized) electrical activity. I get that automaticity of cardiac cells can begin to generate a ventricular rhythm, but VF? It seems more plausible to me that a moving VF vector might produce the appearance of asystole followed by VF in a single monitoring lead. This of course is relevant to the hypothesis that VF may have a vector. Maybe it is more than a hypothesis: documented cases of "occult" VF seem to be strong evidence that VF can have a vector, though the frequency of the phenomenon is unknown (see my article referenced above).
However, it is an idea/question that I did not raise in that article. Asystole changing to ventricular fibrillation (VF) is occasionally documented in the literature (Example: Meaney PA. Rhythms and outcomes of adult in-hospital cardiac arrest. Crit Care Med. 2010; 38(1): 101-8)), but I have never seen a hypothesis for the mechanism of such a metamorphosis. I am no cardiologist, much less an electrophysiologist, but my limited understanding of cardiac electrophysiology makes me wonder how electrical silence could spontaneously morph into frenetic (disorganized) electrical activity. I get that automaticity of cardiac cells can begin to generate a ventricular rhythm, but VF? It seems more plausible to me that a moving VF vector might produce the appearance of asystole followed by VF in a single monitoring lead. This of course is relevant to the hypothesis that VF may have a vector. Maybe it is more than a hypothesis: documented cases of "occult" VF seem to be strong evidence that VF can have a vector, though the frequency of the phenomenon is unknown (see my article referenced above).
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