Three‐dimensional mechanisms of increased vulnerability to electric shocks in myocardial infarction: Altered virtual electrode polarizations and conduction delay in the peri‐infarct zone

•  Defibrillation is known to be less efficient in infarcted than in healthy hearts. •  In a rabbit model of myocardial infarction, altered 3D distribution of virtual electrodes and propagation delay in the peri‐infarct zone caused increased vulnerability to electric shocks in infarcted hearts. •  The infarct scar alone – without the presence of a peri‐infarct zone – did not cause an increase in vulnerability. •  The results help us to understand the mechanisms of increased vulnerability and decreased defibrillation efficacy in infarcted hearts.

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