LAUSR

Management of patients with pacemakers and implantable cardioverter-defibrillators (ICDs) relies in part on the diagnostic features of these sophisticated devices.1 In ICD recipients, appropriately identifying arrhythmias is critical considering that misclassification errors can have dire consequences. Inappropriate shocks from transvenous ICDs adversely impact quality of life and patient well-being, and have been linked to increased mortality.2 Withholding therapies for a misclassified ventricular tachycardia (VT) can lead to hemodynamic collapse before it degenerates into ventricular fibrillation (VF). An analysis of misclassified rhythms is essential in identifying underlying reasons and informing tailored ICD programming to minimize future errors. Effective troubleshooting, therefore, requires the ICD to record and store arrhythmic events. Herein, we present the case of a VT that was not detected or recorded by a subcutaneous ICD (S-ICD).