Diagnoses and outcomes of patients referred for FDG PET/CT for suspected cardiac sarcoidosis.

Abstract

Background: Fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging is commonly used to facilitate diagnosis in suspected cardiac sarcoidosis (CS). However, there is a gap in evidence regarding the diagnoses and outcomes of patients who undergo FDG PET/CT.

Objectives: Evaluate the diagnoses and outcomes of patients referred for FDG PET/CT imaging for suspected CS.

Methods: We studied all consecutive patients referred to our center for FDG PET/CT for suspected CS from June 2006 to November 2023. Patients were characterized by their final clinical diagnosis and followed to a composite outcome of left ventricular assist device placement, heart transplant, or death.

Results: A total of 1646 patients (mean age 58.4 ± 12.4 years; 66 % male) met inclusion criteria: 285 (17.3 %) with Heart Rhythm Society (HRS) criteria positive CS, 83 (5.0 %) with probable CS, 237 (14.4 %) with sarcoidosis but without HRS criteria for CS, and 1041 (63.2 %) with other diagnoses. 227 patients (13.8 %) underwent genetic testing, of whom 32 (14.1 %) were found to have a pathogenic/likely pathogenic variant. Over a median follow up of 4.4 years, 327 patients (19.9 %) met the primary outcome. There was no significant difference in outcomes by diagnosis (log-rank p = 0.4936).

Conclusions: Most patients referred for FDG PET/CT for suspected CS were not found to have CS in follow up. However, they are at similar risk for the need for advanced therapies and many are found to have genetic CMP. These data highlight the importance of advanced heart disease consultation and referral for genetic testing in this population.