Abstract
Sarcoidosis is a multisystem granulomatous disease with a higher incidence in African Americans and Scandinavians. Cardiac sarcoidosis causes arrhythmias, atrioventricular block, heart failure, and sudden death. Elevated high-sensitivity cardiac troponin T (hs-cTnT) and B-type natriuretic peptide (BNP) predict adverse outcomes despite left ventricular ejection fraction (LVEF) normalization. Corticosteroids, implantable cardioverter-defibrillators (ICDs), and angiotensin-converting enzyme (ACE) inhibitors remain key therapies, but evidence is limited, warranting a systematic review. This review searched five databases for English studies on cardiac sarcoidosis up to July 2025. Three observational studies met the patient-exposure-comparison-outcome (PECOS) criteria. Data extraction covered demographics, comorbidities, and hs-cTnT outcomes. Quality was assessed using the National Institutes of Health (NIH) tool, with narrative synthesis due to heterogeneity. This systematic review included three Japanese studies with 258 patients (142 low vs. 116 high hs-cTnT). High hs-cTnT was linked to older age, male predominance, higher BNP, lower LVEF, and worse renal function. Adverse outcomes were significantly more frequent, including cardiac death, ventricular tachycardia (VT)/ventricular fibrillation (VF), heart failure, and hospitalizations. Combined high hs-cTnT and BNP conferred the greatest risk. Imaging showed no major differences except for more right ventricular uptake in high hs-cTnT patients. This review shows that high hs-cTnT strongly predicts poor outcomes in cardiac sarcoidosis, independent of other factors. Combined with BNP, it refines risk stratification. Unlike imaging, hs-cTnT may uncover ongoing myocardial injury, supporting its role in guiding clinical management.