Fact-sheet: Cardiac sarcoidosis
Updated on 11/20/2025 at 8:56 AM
View all RADEOS cases associated with this fact-sheet
Definition
Sarcoidosis is a systemic inflammatory disease characterized pathologically by non-caseating epithelioid and giant cell granulomas.
Pathophysiological hypotheses suggest an inappropriate immune response to environmental or infectious antigens (mycobacteria) in genetically predisposed individuals (HLA-DQB10210, HLA-DRB10301).
Clinical features
Myocardial involvement is more frequent and more severe in African Americans.
Often asymptomatic, discovered during workup for extracardiac manifestations
Nonspecific clinical presentation, but should be suspected in the setting of:
- atrioventricular block before age 60,
- unexplained heart failure,
- severe ventricular arrhythmia.
MRI
Reference examination.
Cardiac sarcoidosis can mimic all phenotypes: hypertrophic, dilated, restrictive, arrhythmogenic, myocarditis, or infarction. It causes fibro-inflammatory granulomatous infiltration of the myocardium.
Late gadolinium enhancement: areas of granulomatous infiltration or fibrosis
A localized area of enhancement in the antero-septo-basal wall extending into the subepicardium of the anterior LV and RV walls, described as a "hook" pattern, is highly suggestive
Enhancement patterns are typically:
- subepicardial, intramyocardial, or transmural
- not confined to a single coronary artery territory
- nodular, patchy
- involving the interventricular septum and the LV posterior wall more than the RV
The presence of late gadolinium enhancement > 10% of the myocardium is a marker of poor prognosis.
Management
Definitive diagnosis: endomyocardial biopsy, whose indications remain very limited and whose sensitivity is low (20-50%).
Classification
The 2014 Heart Rhythm Society guidelines remain the most widely used
Definitive diagnosis: endomyocardial biopsy
Probable Sarcoidosis:
- Histologic diagnosis of extra-cardiac sarcoidosis
- and one of the following criteria: conduction disorder or cardiomyopathy responsive to immunosuppressive therapy
- unexplained LV systolic dysfunction with LVEF < 40%
- unexplained induced or spontaneous sustained ventricular tachycardia
- cardiac hypermetabolism on PET-CT consistent with cardiac sarcoidosis
- late gadolinium enhancement on MRI consistent with cardiac sarcoidosis
- cardiac uptake on gallium-67 scintigraphy consistent with cardiac sarcoidosis
- and absence of any other identifiable cause for the cardiac abnormalities
