A Multidisciplinary Approach in Cardiac Amyloidosis

Abstract Cardiac amyloidosis is an infiltrative condition characterized by the extracellular deposition of insoluble amyloid proteins in myocardial tissue. This accumulation leads to structural and functional remodeling of the heart, resulting in progressive ventricular dysfunction and heart failure with a predominantly restrictive phenotype. Etiologically, cardiac amyloidosis can be primarily classified into forms associated with immunoglobulin light chains (AL) and transthyretin (TTR), either in hereditary or wild-type variants. AL-type amyloidosis represents a secondary manifestation of a systemic plasma cell disorder, with cardiac involvement being associated with a poor prognosis. In contrast, TTR-type amyloidosis has a relatively slower and more favorable clinical course. The use of Tc-99m-labeled bone tracers in scintigraphy enables the confirmation of TTR-type amyloidosis due to specific cardiac uptake. In AL-type amyloidosis, the absence of uptake makes diagnosis confirmation through this method impossible. Conversely, compounds such as Pittsburgh Compound B (C-11 PiB), F-18 florbetaben, and F-18 florbetapir, used in PET-CT, have demonstrated specific uptake in cardiac AL-type amyloidosis. These methods not only allow for the early identification of amyloid deposits but also reduce the need for cardiac biopsy, which was previously considered necessary in many cases. This review aims to present current data on the integration of nuclear medicine technologies into modern cardiology practice, redefining the paradigm for diagnosing and monitoring cardiac amyloidosis. Nuclear cardiology offers a precise, non-invasive, and personalized approach with significant clinical implications, providing valuable support for practicing cardiologists.