18F-FDG PET/CT in Cardiac Sarcoidosis: Pioneering Evidence from the Arab Middle East

Abstract Cardiac sarcoidosis can lead to arrhythmias, heart failure, and sudden cardiac death. Positron emission tomography/computed tomography (PET/CT) is crucial for diagnosis and monitoring, yet data from the Middle East and North Africa (MENA) region remain scarce. This study evaluated the role of PET/CT in diagnosing and managing cardiac sarcoidosis at a tertiary referral center in the Middle East. This retrospective study included 19 patients with biopsy-proven sarcoidosis who underwent fluorine-18 fluorodeoxyglucose (FDG) PET/CT for suspected cardiac involvement at a tertiary referral medical center in Lebanon between 2014 and 2024. Complementary imaging with echocardiography, cardiac magnetic resonance imaging, and electrocardiography was also analyzed alongside treatment approaches and follow-up outcomes. FDG PET/CT identified cardiac involvement in 12 patients, with diffuse or focal FDG uptake patterns correlating with symptom severity and electrocardiographic abnormalities. These patients exhibited higher rates of arrhythmias, conduction abnormalities, and reduced global longitudinal strain and E/A ratio on echocardiography. Cardiac magnetic resonance imaging demonstrated late gadolinium enhancement in most cases with FDG PET/CT-confirmed cardiac sarcoidosis, supporting the presence of myocardial inflammation. Treatment included corticosteroids, immunosuppressive agents, and device implantation in selected cases. Follow-up FDG PET/CT showed significant reductions in FDG uptake, indicating therapeutic response. This study underscores the clinical utility of FDG PET/CT in diagnosing and managing cardiac sarcoidosis, particularly in resource-limited settings like the MENA region. FDG PET/CT enabled early detection, guided treatment decisions, and facilitated monitoring of therapeutic response. These findings highlight the need for broader access to FDG PET/CT imaging in the region to optimize patient outcomes.