Is shock impedance value alone to be considered a good predictor for shock efficacy in subcutaneous implantable cardioverter defibrillator?

Key Clinical Message Subcutaneous implantable cardioverter defibrillator (S‐ICD) is easy to implant, with poor risks of the patient. However, fat is a poor current conductor and increases defibrillation threshold. As shock impedance alone should not be considered a good efficacy predictor of an S‐ICD system, an X‐ray latero‐lateral view for lead position should be achieved. Subcutaneous implantable cardioverter defibrillator (S‐ICD) is easy to implant, with poor risks of the patient. However, fat is a poor current conductor and increases defibrillation threshold. As shock impedance alone should not be considered a good efficacy predictor of an S‐ICD system, an X‐ray latero‐lateral view for lead position should be achieved.