Supplementary Material for: Heart Failure Complicated by Alveolar Hemorrhage due to Vascular Collapse and Amyloid Deposits in Wild-Type Transthyretin Amyloidosis

The main clinical manifestations of wild-type transthyretin (TTR)-related amyloidosis are progressive heart failure and neuropathy. There have been some reports on cerebral hemorrhage due to cerebral amyloid angiopathy in patients with TTR-related amyloidosis, but little is known about the vascular involvement in other organs. A 77-year-old woman experienced heart failure and was admitted for deteriorating heart failure status. Echocardiography showed diffuse hypokinesis of the left ventricle with biventricular wall thickness. On the 12th hospital day, the blood oxygen saturation level suddenly dropped and, despite oxygen supplementation and intensive care, the patient died. An autopsy revealed systemic deposition of amyloids which were immunolabeled by an anti-TTR antibody. Furthermore, gene-sequencing analysis showed no evidence of TTR gene mutations. The patient was diagnosed postmortem with wild-type TTR-related amyloidosis. Pathological findings revealed alveolar hemorrhage of the lung. Massive amyloid deposits were present in the vessels, and collapsed internal elastic laminae with lymphocyte infiltration were observed at the site of amyloid deposits in the bronchial artery, suggesting that deposits with inflammation might cause the collapse of the bronchial artery and lead to hemorrhage. In amyloidosis patients who suffer heart failure, there is the potential for vascular collapse caused by the accumulation of amyloid deposits with inflammation.