Plasma level of big endothelin-1 predicts the prognosis in patients with hypertrophic cardiomyopathy

Cardiac remodeling is one of major pathological process in hypertrophic cardiomyopathy (HCM). Endothelin-1 has been linked to cardiac remodeling. Big endothelin-1 is the precursor of endothelin-1.A total of 245 patients with HCM were enrolled from 1999 to 2011 and partitioned to low, middle and high level groups according to their plasma big endothelin-1 levels.At baseline, significant associations were found between high level of big endothelin-1 and left atrium size, heart function and atrial fibrillation. Big endothelin-1 was positively correlated with N-terminal B-type natriuretic peptide (r=0.291, p0.001) and late gadolinium enhancement (LGE) on magnetic resonance imaging (r=0.222, p=0.016). During a follow-up of 3 (range, 2-5) years, big endothelin-1 level was positively associated with the risks of all-cause mortality, cardiovascular death and progression to NYHA class 3 or 4 (p=0.020, 0.044 and 0.032, respectively). The rate of above events in the highest tertile were 18.1%, 15.7%, 24.2%, respectively. After adjusting for multiple factors related to survival and cardiac function, the significance remained in the association of big endothelin-1 with the risk of all-cause mortality (hazard ratio (HR)=4.94, 95% confidence interval (CI) 1.07-22.88; p=0.041) and progression to NYHA class 3 or 4 (HR=4.10, 95%CI 1.32-12.75, p=0.015).Our study showed that high level of plasma big endothelin-1 predicted prognosis for patients with HCM and it can be added to the marker panel in stratifying HCM patients for giving treatment priority to those at high risk.