[A woman in her fifties with left bundle branch block and recurrent arrhythmias].

Background: Sarcoidosis is a multi-system inflammatory disorder resulting in the formation of non-caseating granulomas in various parts of the body. Cardiac involvement is associated with worse prognosis, probably due to the destructive effects the granulomas can have on the electrical conduction system. The diagnosis of cardiac sarcoidosis can be challenging due to the limited accuracy of various clinical criteria.

Case Presentation: A woman in her fifties developed symptoms in the form of dry cough and uncharacteristic chest pain. Thorough assessment was initiated, but the true cause remained undiagnosed for several years. The patient suffered from recurrent arrythmias and eventually a weakened ventricular function and cardiac failure. A multidisciplinary approach revealed that the patient was suffering from cardiac sarcoidosis.

Interpretation: Cardiac sarcoidosis may initially present with mild symptoms, but left bundle branch block, total AV-block and supraventricular tachycardias, as well as weakened ventricular function, should raise suspicion of the condition. Magnetic resonance imaging and echocardiography may be of help during clinical assessment, and positron emission tomography/computed tomography and biopsy can confirm the condition.