Cardiac sarcoidosis

Sarcoidosis is characterized by non-caseating granulomas in multiple organs. Cardiac symptoms are seen in 5% of patients with cardiac sarcoidosis and include complete heart block, ventricular arrhythmias, heart failure, pericardial effusion, ventricular aneurysm, pulmonary hypertension and sudden cardiac death. Endomyocardial biopsy is the gold standard for the diagnosis, although it has low yield due to random nature of the disease. Several imaging modalities are used in the diagnosis and management of sarcoidosis, each with their advantages and disadvantages. Echocardiography has a limited role and is non- specific. Nuclear scintigraphy techniques such as Gallium-67 scan and myocardial perfusion imaging are also used either separately or in combination to evaluate for myocardial inflammation. PET scan with 18F-FDG is used for evaluating myocardial inflammation. Magnetic resonance imaging (MRI) is the most important imaging modality due to its high spatial and temporal resolution and tissue characterization capabilities and provides information on diagnosis, prognosis, risk stratification and therapy response. In this chapter, we will review the clinical and imaging features of cardiac sarcoidosis.