Ventricular tachycardia oversensing in S‐ICD patients: Case‐based brief review

A 76‐year‐old woman with permanent atrial fibrillation and a mechanical aortic valve came to our attention. Echocardiography showed a 50‐55% ejection fraction (EF) with good prosthesis performance. For symptomatic bradyarrhythmia, she received a VVI pacemaker (Proponent MRI L2010 model; Boston Scientific.). During follow‐up, frequent symptomatic (presyncopal) episodes of nonsustained episodes of ventricular tachycardia (VT) were detected. Amiodarone proved unsuccessful; she was then offered an upgrade to an implantable cardioverter defibrillator (ICD) and a subcutaneous ICD (S‐ICD) was chosen by the patient. A few weeks later, two sustained VT were detected and effectively treated with 80‐J shock delivery. In both cases, device interrogation revealed a VT rate around 163 bpm (370 ms cycle length), below the lowest device detection cutoff. The report is a case‐based review.