Insight from an autopsy in a patient with rapidly worsening heart failure due to amyloid light-chain cardiac amyloidosis: A case report

Abstract Amyloid light-chain (AL) amyloidosis is a systemic disease characterized by the deposition of misfolded immunoglobulin light chain, causing organ failure, and in particular cardiac involvement is a leading cause of morbidity and mortality. We report the case of a 47-year-old man without prior cardiovascular events who presented with shortness of breath. He was diagnosed with primary AL cardiac amyloidosis (CA) from the laboratory test, the endomyocardial biopsy, the bone marrow examination, and the cardiovascular imaging. Only a week after discharge of the first heart failure (HF) admission, he was readmitted for the exacerbation of HF. Finally, he died 2 weeks after the second admission, that is 3 months after the onset of HF. Autopsy, which was performed to investigate the causes of rapid worsening HF, implied the impairment of ventricular function and coronary microcirculation dysfunction. We could diagnose CA immediately by using diagnostic tools, however, we recognized that there was the fulminant type in CA, and considered the insight from autopsy. 〈Learning objective: This case demonstrates a young patient with cardiac amyloidosis (CA) developed rapid worsening heart failure (RWHF), and then he died 1 month after diagnosis, that is 3 months after the onset of heart failure. This case deems to be a fulminant type in amyloid light-chain CA, and autopsy suggested the mechanisms of RWHF, which are the impairment of ventricular function and coronary microcirculation dysfunction.〉