Hidden under the Surface: A Rare Cause of Repeated Syncope in a Patient with Recent Pacemaker Implantation

A 66-year-old woman received a pacemaker implantation because of syncope with documented sinus arrest and junctional bradycardia. Three weeks later the pacemaker analysis revealed episodes of nonsustained ventricular tachycardia. Coronary angiography and invasive coronary assessment showed diffuse moderate stenosis but no significant ischemia. Three months later she experienced a new syncope and the pacemaker analysis showed runs of nonsustained ventricular tachycardia at the time of syncope. The combination of brady- and tachyarrhythmias raised concern for cardiac sarcoidosis. 18F-fluorodeoxyglucose positron emission tomography (PET) scan showed increased FDG uptake in the basal segments compatible with inflammatory disease. Cardiac magnetic resonance imaging showed late gadolinium enhancement in the same region of the PET-avid lesions. Diagnostic electrophysiologic study could induce VT. The diagnosis of cardiac sarcoidosis was made, for which high dose corticosteroids were prescribed and an upgrade to a dual chamber implantable cardioverter defibrillator was performed. Because of the localization of the lesions, an endomyocardial biopsy was not performed. All the lesions regressed completely on PET-scan after treatment with high dose corticosteroids.