Big Endothelin-1 Predicts the long-term survival in patients undergoing septal myectomy

Background The prognostic role of endothelin-1 (ET-1) in patients with obstructive hypertrophic cardiomyopathy (oHCM) who underwent septal myectomy remains unclear. We aimed to assess its prognostic importance in patients undergoing septal myectomy. Methods We recruited 1207 oHCM patients for this analysis. The participants were divided into three groups according to the tertile of big ET-1. Cox regression analyses were conducted to assess the prognostic value of big ET-1 on all-cause death and cardiovascular death. Results The mean age of the participants was 49.9 ± 12.0 years, 713 (59%) study patients were male. female (adjusted coefficient 0.106, 95% CI: 0.053–0.158) and left atrial dimension (adjusted coefficient 0.005, 95%CI: 0.001–0.009) were significantly associated with big ET-1 levels. During mean 3.8 years follow-up, 35 patients died including 27 cardiovascular deaths. Multivariate Cox regression analyses showed that patients with highest tertile had the highest incidence of all-cause mortalities (adjusted HR = 3.483, 95% CI: 1.365–8.887, P = 0.009) and cardiovascular mortalities (adjusted HR = 8.328, 95%CI: 1.883–36.828, P = 0.005), compared to the referenced patients with lowest tertile. When Big ET-1 was evaluated as a continuous variable, data showed that the big ET-1 was correlated with higher risks of all-cause deaths (adjusted HR = 1.588, 95%CI: 1.148–2.196, P = 0.005) and cardiovascular deaths (adjusted HR = 1.757, 95%CI: 1.250–2.470, P = 0.001). Furthermore, interactions were detected in the subgroups of gender, and maximum wall thickness. Conclusion Our study revealed that high level of plasma big ET-1 could predict worse clinical outcomes for oHCM patients undergoing myectomy.