Cardiac Sarcoidosis Diagnostic Probability Score (HRS adaptation)

Myocardial biopsy shows non-caseating granulomas

Histologic extracardiac sarcoidosis confirmed

High-grade AV block (Mobitz II or third-degree)

Unexplained sustained ventricular tachycardia

Left ventricular ejection fraction (LVEF) %

Cardiac FDG-PET: focal/patchy uptake consistent with CS

Cardiac MRI (CMR): LGE pattern typical/compatible with CS

Myocardial perfusion defect (SPECT/PET) consistent with CS

Steroid-responsive cardiomyopathy or heart block

Reasonable alternative diagnoses excluded

Cardiac Sarcoidosis Diagnostic Probability Score (HRS adaptation): Explanation and Clinical Context
This calculator operationalizes the 2014 Heart Rhythm Society (HRS) consensus statement on cardiac sarcoidosis. A definitive diagnosis requires myocardial biopsy showing non-caseating granulomas, whereas a probable diagnosis requires histologically proven extracardiac sarcoidosis plus one or more typical cardiac features and exclusion of other causes. Typical cardiac features include high-grade AV block, sustained VT, unexplained reduced LVEF, characteristic FDG-PET uptake, CMR with LGE, perfusion defect compatible with CS, or steroid-responsive cardiomyopathy. The exploratory probability index is a heuristic, non-validated scoring framework designed to approximate diagnostic confidence, not to replace the categorical HRS definitions.

References:
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Aftab A, et al. Front Cardiovasc Med. 2024.