Mechanisms of Induction and Termination of Ventricular Fibrillation
The mechanisms of the induction and defibrillation of ventricular fibrillation (VF) by electrical field stimuli have gained an increasing interest since the first implantation of the implantable cardioverter defibrillator (ICD) in 1980. During the past years, the initiation of VF by T wave shocks has been used clinically to determine the defibrillation threshold for ICD testing. In addition, T wave shock-induced VF is of scientific importance since it has been observed that there is a direct relationship between the defibrillation threshold (DFT) and the upper limit of vulnerability (ULV) [1, 2]. The upper limit of vulnerability reflects the highest shock strength above which VF is not inducible regardless of the shock coupling interval . The close correlation between the upper limit of vulnerability and the defibrillation threshold suggests that there is a common mechanism of both VF induction and VF termination by electrical field stimuli . A better understanding of VF induction may therefore lead to more insights into defibrillation.
KeywordsVentricular Fibrillation Ventricular Repolarization Monophasic Action Potential Isolate Rabbit Heart Defibrillation Threshold
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