Concurrent Therapy for Immunoglobulin Light Chain Cardiac Amyloidosis and Transthyretin Cardiac Amyloidosis: A Case Report

Cardiac amyloidosis (CA), predominantly caused by amyloid transthyretin (ATTR) or immunoglobulin light chain (AL), has a poor prognosis, and a precise diagnosis is crucial because the optimal treatments differ between the two conditions. However, diagnosing AL-CA is challenging because of the unavailability of effective AL-detecting antibodies, particularly in cases with coexisting AL- and ATTR-CA. This report presents a successfully diagnosed case of complicated AL- and ATTR-CA that was successfully treated with tafamidis for ATTR-CA and combination chemotherapy for AL-CA. This case highlights the importance of a precise diagnosis of CA and supports the efficacy and safety of concurrent treatment for coexisting amyloidosis.