Emergency department admissions due to implantable cardioverter-defibrillator (ICD) shocks constitute an important patient group. The correct evaluation includes a review of system integrity and a careful analysis of stored intracardiac electrograms. We present a patient admitted with a single ICD discharge due to an episode of sustained monomorphic ventricular tachycardia, and an unexpected finding.
Keywords: Cardioverter-defibrillator; evaluation; shock.