Incidence, clinical characteristics, and diagnostic approach in transthyretin amyloid cardiomyopathy: The Kumamoto Cardiac Amyloidosis Survey

•The epidemiology of transthyretin amyloid cardiomyopathy (ATTR-CM) is not yet understood in Japan.•We conducted a retrospective multicenter observational cohort study in Kumamoto.•The incidence of ATTR-CM was about 1 per 10,000 person-years in the elderly.•Age at diagnosis was older in the regional hospitals than referral facilities.•Possible ATTR-CM was more frequent in the regional hospital cohort. In recent years, transthyretin amyloid cardiomyopathy (ATTR-CM) has received increasing attention; however, the epidemiology of ATTR-CM in Japan is not yet understood. In the Kumamoto Cardiac Amyloid Survey, we evaluated the current incidence, clinical characteristics, diagnostic approaches, and treatment strategies for ATTR-CM and compared tafamidis-prescription hospitals with regional hospitals. We conducted a retrospective multicenter observational cohort study. The registry included patients with ATTR-CM diagnosed in two tafamidis-prescription hospital institutes [Japanese Circulation Society (JCS)-certified facilities] and 15 regional cardiovascular facilities in Kumamoto between January 2018 and December 2020. In total, 174 patients were diagnosed with ATTR-CM. The incidence of ATTR-CM was estimated to be approximately 1 per 10,000 person-years in the elderly population (>65 years old) in Kumamoto. Compared with that in the JCS-certified facilities cohort (n=115), age at diagnosis was significantly older (84.5 ± 5.6 vs. 77.5 ± 6.3 years old; p