Effect of β-Blockers on the Left Ventricular Strain in Patients With Wild-Type Transthyretin Amyloid Cardiomyopathy Treated With Tafamidis.

Background: Although tafamidis is used in patients with wild-type transthyretin cardiac amyloidosis (ATTRwt-CM), the effects of β-blockers, one of the conventional heart failure medications, are unclear. Therefore, this study aimed to investigate the effect of β-blockers on left ventricular function using speckle-tracking echocardiography after 1 year of treatment in patients with ATTRwt-CM. Methods and Results: We included 46 patients (median age, 78 years) with ATTRwt-CM confirmed via biopsy. We analyzed laboratory and echocardiographic data, including global longitudinal strain (GLS) to determine left ventricular strain, using 2D speckle-tracking echocardiography and compared the changes in these parameters before and 1 year after treatment with tafamidis between 24 patients who did not receive β-blockers and 22 patients who received β-blockers. The absolute GLS deterioration was higher in patients taking β-blockers by a mean of 0.48±1.55% compared with -0.68±1.65% in patients not taking β-blockers (P=0.0181). However, other conventional heart failure medications showed no change in the GLS. Conclusions: Left ventricular function may deteriorate with the use of β-blockers in patients with ATTRwt-CM treated with tafamidis for 1 year.