PURPOSE: Amyloid transthyretin cardiomyopathy (ATTR-CM) treatment guidelines do not align in their recommendations of which patients should receive transthyretin stabilizers based on New York Heart Association (NYHA) classification. We conducted a meta-analysis to assess the impact of transthyretin stabilizers on outcomes in patients with ATTR-CM in different NYHA classification subgroups. METHODS: We searched PubMed, the Cochrane Central Register of Controlled Trials, trial registers, and regulatory agency websites through July 2025 to identify randomized controlled trial data for transthyretin stabilizers reporting on all-cause mortality (ACM) and/or frequency of cardiovascular hospitalization (CVH) and 6-meter walk distance (6MWD) stratified by NYHA classification at baseline. We pooled effect estimates with 95% confidence intervals (CIs) using random-effects methods. RESULTS: We identified 2 RCTs with a total of 1,052 participants, of whom 77.2% had NYHA class I or II disease and the remainder had class III disease. In the NYHA class I/II subgroup, all outcomes showed benefit with treatment compared to placebo: greater effectiveness in reducing ACM or CVH frequency (win ratio, 1.79; 95% CI, 1.40-2.30), reduced hazard of ACM (hazard ratio, 0.64; 95% CI, 0.46-0.88) and rate ratio of CVH (rate ratio, 0.46; 95% CI, 0.38-0.57), and improved 6MWD (least-squares mean difference, 65.16; 95% CI, 25.85-104.48). In the NYHA class III subgroup, no differences were found for treatment vs placebo. CONCLUSION: Transthyretin stabilizers showed beneficial effects on all outcomes when assessed in patients with NYHA class I/II disease, but no benefit was found in the NYHA class III subgroup. These findings reinforce the importance of early-stage ATTR-CM diagnosis and treatment.
Fan et al. (Sat,) studied this question.