Vibratory alert in a recalled implantable cardioverter-defibrillator: Is there something wrong with the device?

Case report A 56-year-old man with a longstanding, dilated cardiomyopathy came to the EmergencyDepartment after noting a “buzzing” sensation from his implantable cardioverter-defibrillator (ICD). The device was a Unify Assura (St. Jude Medical, St. Paul, MN) that had been placed as a pulse generator replacement in February 2014. In October 2016, St. Jude Medical initiated a class I recall for certain models of the Fortify, Unify, and Assura ICDs due to an approximately 0.2% incidence of premature and potentially rapid battery depletion. Interrogation confirmed normal battery longevity and lead parameters with the following programmed settings: DDDR 60–130 beats per minute (bpm) with a paced and sensed atrioventricular (AV) delay of 180 and 130 ms; LV/ RV offset 20 ms; postventricular atrial refractory period (PVARP) 375 ms; ventricular tachycardia (VT) zone 187 bpm; and ventricular fibrillation (VF) zone 214 bpm. Thevibratory alertwas for “nonsustainedRVoversensing” (Figure 1). Is there a problem with lead integrity?