[Complete atrioventricular block of the young adult... do not forget sarcoidosis].

The authors report the case of a 27 years old athletic patient, without any antecedents, presenting with a recent complete atrioventricular (AV block, disclosed by an effort dyspnoea and syncope. The electrophysiological exploration showed a nodal AV block. The magnetic resonance imaging revealed the existence of a septal hypersignal in T1 mode enhanced after Gadolinium injection, and left ventricular function normality. It also revealed the existence of a pulmonary parenchyma infiltrate, confirmed by thoracic scanner. Pathological examination of transbronchial biopsies showed noncaseating granuloma, consistent with sarcoidosis. Programmed electrical stimulation induced no ventricular arrhythmia. A dual chamber pace-maker was implanted because of the AV block permanence and the poor clinical tolerance, associated with steroid therapy (prednisolone 1 mg/kg/j). After a 18 months follow-up, the patient remains asymptomatic, and the 12-lead ECG shows a normal AV conduction. The authors discuss the different aetiologies of AVB, and emphasize to realize an exhaustive assessment in young adults. The cardiac localization disclosing sarcoïdosis and the complete AV block disappearance under therapy make that observation original. The occurrence of a complete AV block complicating sarcoidosis poses a management and prognosis problem.