Survival After Septal Reduction in Patients >65 Years Old With Obstructive Hypertrophic Cardiomyopathy.

Abstract

Obstructive hypertrophic cardiomyopathy (oHCM) is increasingly being diagnosed in elderly patients. The authors sought to study long-term outcomes of septal reduction therapies (SRT) in Medicare patients with oHCM, and hospital volume-outcome relation. Medicare beneficiaries aged >65 years who underwent SRT, septal myectomy (SM) or alcohol septal ablation (ASA), from 2013 through 2019 were identified. Primary outcome was all-cause mortality, and secondary outcomes included heart failure (HF) readmission and need for redo SRT in follow-up. Overlap propensity score weighting was used to adjust for differences between both groups. Relation between hospital SRT volume and short-term and long-term mortality was studied. The study included 5,679 oHCM patients (SM = 3,680 and ASA = 1,999, mean age 72.9 vs 74.8 years, women 67.2% vs 71.1%; P < 0.01). SM patients had fewer comorbidities, but after adjustment, both groups were well balanced. At 4 years (IQR: 2-6 years), although there was no difference in long-term mortality between SM and ASA (HR: 0.87; 95% CI: 0.74-1.03; P = 0.1), on landmark analysis, SM was associated with lower mortality after 2 years of follow-up (HR: 0.72; 95% CI: 0.60-0.87; P < 0.001) and had lower need for redo SRT. Both reduced HF readmissions in follow-up vs 1 year pre-SRT. Higher-volume centers had better outcomes vs lower-volume centers, but 70% of SRT were performed in low-volume centers. SRT reduced HF readmission in Medicare patients with oHCM. SM is associated with lower redo and better long-term survival compared with ASA. Despite better outcomes in high-volume centers, 70% of SRT are performed in low-volume U.S. centers.