Characteristics and prognosis of patients with cardiac sarcoidosis presenting with atrioventricular block and ventricular arrhythmias

Abstract

Cardiac sarcoidosis (CS) may initially present with life-threatening arrhythmias such as atrioventricular block (AVB) and ventricular arrhythmia (VA), including ventricular tachycardia and ventricular fibrillation. Diagnosing CS is challenging due to subtle or absent findings in routine tests and the low sensitivity of the definitive diagnostic tool, endomyocardial biopsy. CS can also mimic other cardiac conditions such as dilated cardiomyopathy or arrhythmogenic right ventricular cardiomyopathy, and it may occur without any systemic involvement. Consequently, delays in presentation, accurate diagnosis, and initiation of appropriate treatment are frequent. Greater awareness of the condition could improve outcomes for patients with CS. Non-invasive advanced imaging techniques, such as 18F-fluorodeoxyglucose positron emission tomography and cardiac magnetic resonance imaging are essential for diagnosis, although they may not be accessible in all clinical settings. Management of arrhythmias in CS involves conventional therapies in the utilization of antiarrhythmics and non-pharmacological therapy (e.g., implantable devices), but with notable divergences in the use of immunosuppression and a preference for implantable cardioverter defibrillators over permanent pacemakers. This narrative review aimed to outline the clinical features of patients with CS presenting with AVB or VA and examine diagnostic investigations, imaging techniques, treatment approaches, and prognosis based on current research and international guidelines.