Using Nanosecond Shocks for Cardiac Defibrillation.

Bioelectricity

Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia.

Published: December 2019


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Article Abstract

The purpose of this review article is to summarize our current understanding of the efficacy and safety of cardiac defibrillation with nanosecond shocks. Experiments in isolated hearts, using optical mapping of the electrical activity, have demonstrated that nanosecond shocks can defibrillate with lower energies than conventional millisecond shocks. Single defibrillation strength nanosecond shocks do not cause obvious damage, but repeated stimulation leads to deterioration of the hearts. In isolated myocytes, nanosecond pulses can also stimulate at lower energies than at longer pulses and cause less electroporation (propidium uptake). The mechanism is likely electroporation of the plasma membrane. Repeated stimulation leads to distorted calcium gradients.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359641PMC
http://dx.doi.org/10.1089/bioe.2019.0030DOI Listing

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