PO-687-02 THE EXTRAVASCULAR IMPLANTABLE CARDIOVERTER - DEFIBRILLATOR: A CASE FOR CONCERN

Abstract

The investigational Extravascular Implantable Cardioverter Defibrillator (Medtronic EV-ICD) system with its substernal lead placement may offer an alternative to transvenous ICD while reducing the risks associated with transvenous system such as infection requiring extraction, vascular injury, and venous obstruction. The EV-ICD lead is placed just beneath the sternum in the retrosternal space. Patients with prior or planned sternotomy and prior chest radiotherapy are excluded from the EV-ICD trials due to increased surgical risk. We describe a patient with cardiac sarcoidosis in whom we decided not to implant the EV-ICD due to pericardial adhesions noted on preoperative imaging. N/A A 55-year-old man with history of chronic systolic heart failure due to cardiac sarcoidosis and family history of sudden cardiac death was noted to have non sustained ventricular tachycardia on an event monitor. He underwent an electrophysiologic study which showed inducible monomorphic ventricular tachycardia. ICD implantation was recommended. Due to an active lifestyle and no pacing indication, he opted for an EV-ICD. As part of the pre-operative protocol, a chest X ray is obtained but is not used to determine device eligibility. However, in this case it was noted that the right ventricle was closely approximated to the sternum. Due to history of inflammatory cardiomyopathy, a gated cardiac CT was obtained to evaluate the retrosternal space. Cardiac CT showed adhesion of the right ventricular pericardium to the midline sternum. The right ventricle was tethered but not adherent to the sternum. The EV-ICD procedure was cancelled due to increased surgical risk associated with tunneling with an adherent pericardium. He later underwent a transvenous ICD placement. Pericardial adhesions may be associated with inflammatory cardiomyopathies such as cardiac sarcoidosis. Thorough preoperative evaluation of the retrosternal space is recommended in such patients prior to considering substernal lead tunneling.