CCM efficacy in ATTR cardiomyopathy with mr to r EF and nyha III orIV

Background/Introduction Transthyretin amyloid cardiomyopathy (ATTR-CM) is an infiltrative disease often leading to symptomatic heart failure (HF) with mildly reduced or reduced ejection fraction (EF). Standard medical therapy is limited in advanced stages (NYHA III–IV), and Tafamidis is indicated only in early phases. Cardiac contractility modulation (CCM) therapy improves outcomes in HF with reduced EF, but its role in ATTR-CM remains unexplored. Methods This prospective multicenter pilot study evaluated the safety and efficacy of CCM in ten patients with ATTR-CM, EF 25–45%, and NYHA III–IV symptoms refractory to optimal medical therapy. All underwent Optimizer CCM implantation and were followed for a median of 12 months. The primary endpoint was worsening heart failure (WHF); secondary endpoints included changes in EF, NYHA class, 6-minute walk test (6MWT), and quality-of-life parameters. Results CCM therapy significantly reduced WHF events (from 0.18 ± 0.09 to 0.025 ± 0.08 hospitalizations/year, p<0.001) and improved NYHA class (from 3.2 ± 0.4 to 2.0 ± 0.0, p<0.001). EF increased by 4.8 ± 6.1%, and 6MWT improved by 31.3 ± 53.3%. Notably, all patients became eligible for Tafamidis due to functional improvement. Conclusions CCM appears feasible and potentially effective in advanced ATTR-CM patients not eligible for disease-modifying therapy. These findings warrant larger studies, including the ongoing AMY-CCM registry (NCT05167799), to validate the therapeutic role of CCM in this population.