Imaging Cardiac Amyloidosis: From Early Diagnosis to Risk Stratification and Evaluation of Treatment Efficacy

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy caused by extracellular deposition of misfolded proteins, most commonly immunoglobulin light chains (AL) or transthyretin (ATTR). Once considered a rare disease, CA is increasingly recognised due to improved diagnostic strategies and the availability of disease-modifying therapies. Early diagnosis is crucial, as treatment efficacy and clinical outcomes are strongly influenced by the stage of cardiac involvement. Multimodality cardiac imaging plays a central role in the diagnostic pathway, risk stratification, and evaluation of therapeutic response in CA. Echocardiography represents the first-line imaging modality and is essential for raising clinical suspicion through the identification of characteristic structural and functional abnormalities, including ventricular wall thickening, diastolic dysfunction, and distinctive strain patterns. Bone scintigraphy has revolutionised the non-invasive diagnosis of ATTR-CA, allowing accurate identification of transthyretin-related disease in the absence of monoclonal gammopathy, which needs to be excluded via serum and urinary immunofixation. Cardiovascular magnetic resonance provides advanced tissue characterisation through late gadolinium enhancement and quantitative mapping techniques, enabling detection of early myocardial involvement and robust prognostic stratification. Emerging imaging modalities, including dual-energy (spectral) computed tomography and positron emission tomography tracers, show promise in myocardial amyloid quantification and subtype differentiation, although their role is still evolving. Integration of imaging findings with clinical and laboratory parameters allows comprehensive disease assessment, facilitating early diagnosis, guiding therapeutic decisions, and improving risk stratification. This review summarises the current role of multimodality imaging in CA, highlighting its contribution from early detection to prognostic evaluation and monitoring of treatment efficacy, with particular emphasis on the emerging role of quantitative imaging in monitoring treatment response.