Initial Experience With Tafamidis Treatment for Transthyretin Amyloid Cardiomyopathy.

Background: Transthyretin amyloid cardiomyopathy is a progressive disease with a poor prognosis. There had been no specific treatment for transthyretin amyloid cardiomyopathy until tafamidis received expanded approval in March 2019 in Japan. However, the clinical efficacy of tafamidis remains unknown. Methods and Results: We initiated tafamidis treatment in 9 patients (median age 78 years; 89% male) from May 2019 to April 2020. Within 6 months after initiation, 1 patient discontinued prematurely and 2 patients were hospitalized due to worsening heart failure, with 1 of these patients discontinuing therapy. There were no significant changes in plasma B-type natriuretic peptide and serum troponin I concentrations over the 6-month treatment period, but interventricular septum thickness increased in 3 of 6 patients. Conclusions: Further evaluation of tafamidis therapy in a larger patient cohort with transthyretin amyloid cardiomyopathy is warranted to determine the optimal therapeutic strategy.