Localization of myocardial FDG uptake for prognostic risk stratification in corticosteroid-naïve cardiac sarcoidosis.

The localization of myocardial 18F-fluorodeoxyglucose (FDG) uptake affecting long-term clinical outcomes has not been elucidated in patients with corticosteroid-naive cardiac sarcoidosis (CS). This study sought to investigate the localization of myocardial FDG uptake on positron emission tomography (PET) and myocardial perfusion abnormality to predict adverse events (AEs) for a long-term follow-up in patients with corticosteroid-naive CS. Consecutive 90 patients with clinical suspicion of CS who underwent FDG-PET imaging to assess for inflammation were enrolled. AEs were defined as a composite of sustained ventricular tachycardia (VT), heart transplantation, and all-cause death, which were ascertained by medical records, defibrillator interrogation, and telephone interviews. Of 90 patients, 42 patients (mean age 62.9 ± 12.0 years; 76.2% females) were confirmed active cardiac involvement. Over a median follow-up of 4.9 years, 15 patients with CS experienced AEs including 6 sustained ventricular tachycardias (VT) and 9 deaths. Cox proportional-hazards model after adjustment for left ventricular systolic dysfunction revealed that FDG uptake in the right ventricle (RV) or basal anterolateral area of the left ventricle (LV) with myocardial perfusion abnormality was predictive of AEs. FDG uptake in the RV or basal anterolateral area of the LV with myocardial perfusion abnormality provides long-term prognostic risk stratification in patients with corticosteroid-naive CS.