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Updated: May 14, 2026
07:56
A Model of Long-Term Ventricular Fibrillation in Isolated Rat Hearts
Published on: February 17, 2023
The stability of electrically induced ventricular fibrillation
Mark W Kroll1, Gregory P Walcott, Raymond E Ideker
1Biomedical Engineering Dept., University of Minnesota, Minneapolis, MN, USA. kroll051@umn.edu
Summary
Electrically induced ventricular fibrillation (VF) in swine persisted for a median of 35 minutes, even without chest compressions. This finding suggests VF is long-lived and may impact electrocution diagnosis.
Area of Science:
- Cardiology
- Emergency Medicine
- Forensic Science
Background:
- The initial heart rhythm in cardiac arrest is crucial for treatment.
- Ventricular fibrillation (VF) is treatable, unlike asystole or pulseless electrical activity (PEA).
- The progression of VF to asystole or PEA is not well understood.
Purpose of the Study:
- To investigate the time course of electrically induced VF deterioration in a swine model.
- To inform emergency response protocols and improve the diagnosis of electrocution injuries.
Main Methods:
- Ventricular fibrillation (VF) was induced in 6 ventilated swine via electrical stimulation.
- Animals were monitored for 40 minutes without circulatory assistance.
- Deterioration of VF to asystole or PEA was recorded and analyzed.
Main Results:
- The median time for VF deterioration was 35 minutes.
- VF persisted in all animals for at least 24 minutes.
- 2 swine remained in VF, 3 progressed to asystole, and 1 to PEA.
Conclusions:
- Electrically induced VF is remarkably long-lived, even without chest compressions.
- Understanding VF duration is vital for emergency medical services and electrocution incident analysis.
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