真鍋 治

Cardiac amyloidosis, characterized by extracellular deposition of amyloid fibrils within the myocardium, is an increasingly recognized cause of heart failure. With the advent of disease-modifying therapies, imaging has become central to diagnosis, subtype differentiation, prognostication, and treatment monitoring. This review provides a comprehensive update on multimodality imaging in cardiac amyloidosis, emphasizing its clinical utility across the disease continuum. Echocardiography, technetium-labeled bone scintigraphy, amyloid-specific positron emission tomography, cardiac magnetic resonance, and cardiac computed tomography each contribute uniquely to detecting amyloid burden and assessing cardiac function. In addition to outlining a practical diagnostic approach, we highlight emerging imaging biomarkers for monitoring treatment response and predicting clinical outcomes. The integration of these modalities into clinical practice enhances diagnostic accuracy, enables individualized risk stratification, and supports optimized, evidence-based care for patients with cardiac amyloidosis.

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.

Cardiovascular inflammation has recently emerged as a critical issue across various cardiovascular diseases. Various non-invasive imaging modalities are applied for assessing cardiovascular inflammation. Positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) is a valuable non-invasive imaging tool for identifying active cardiovascular inflammation. It is utilized in evaluating conditions, such as cardiac sarcoidosis, endocarditis, vasculitis, and unstable atherosclerosis. Furthermore, management of cardiovascular complications after aggressive cancer therapy has increasingly been required in cancer patients. FDG PET is considered a suitable approach not only for the assessment of tumor responses to cancer therapy, but also for early and accurate detection of cardiovascular complications. This review highlights the clinical value of FDG PET under appropriate patient preparation. The future perspectives of new molecular imaging tools for assessing active cardiovascular inflammation have been described.