– Older implantable cardioverter defibrillator units use patch electrodes instead of leads
• If transthoracic shocks of up to 360 J fail to defibrillate patient with implantable cardioverter defibrillator, chest electrode positions should be changed immediately (e.g.,anterior‐apex to anteroposterior)
• Electrodes cover portion of epicardial surface
• May reduce amount of current delivered to heart from transthoracic shocks