Updates on Cardiac MRI and PET Imaging for the Diagnosis and Monitoring of Cardiac Sarcoidosis

Cardiac sarcoidosis (CS) poses significant diagnostic and therapeutic challenges due to its heterogeneous clinical manifestations and the limitations of conventional diagnostic approaches. Advances in imaging modalities, particularly cardiac magnetic resonance imaging (CMR) and ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET), have revolutionized the evaluation and management of this complex condition. CMR, with its superior spatial resolution and advanced techniques such as late gadolinium enhancement, T1/T2 mapping, and extracellular volume quantification, offers unparalleled insights into myocardial structure and fibrosis. These techniques not only enhance diagnostic accuracy but also provide critical information on disease activity and treatment response. Among these, T2 mapping has emerged as a valuable marker for active inflammation, with high values reliably indicating acute disease states. FDG-PET serves as a complementary modality by detecting active granulomatous inflammation and guiding immunosuppressive therapy. The synergistic integration of CMR and FDG-PET provides a comprehensive approach to diagnosing and monitoring CS, enabling the identification of subclinical disease and the optimization of therapeutic strategies. Furthermore, the incorporation of quantitative biomarkers, such as strain metrics and T2 values, promises to refine disease assessment and management. These advancements have the potential to transform the paradigm of CS care, ultimately improving patient outcomes.