Plasma big endothelin-1 is an effective predictor for ventricular arrythmias and end-stage events in primary prevention implantable cardioverter- defibrillator indication patients.

OBJECTIVE: To investigate whether plasma big endothelin-1 (ET-1) predicts ventricular arrythmias (VAs) and end-stage events in primary prevention implantable cardioverter-defibrillator (ICD) indication patigents.

METHODS: In total, 207 patients fulfilling the inclusion criteria from Fuwai Hospital between January 2013 and December 2015 were retrospectively analyzed. The cohort was divided into three groups according to baseline plasma big ET-1 tertiles: tertile 1 (< 0.38 pmol/L, n = 68), tertile 2 (0.38-0.7 pmol/L, n = 69), and tertile 3 (> 0.7 pmol/L, n = 70). The primary endpoints were VAs. The secondary endpoints were end-stage events comprising all-cause mortality and heart transplantation.

RESULTS: During a mean follow-up period of 25.6 ± 13.9 months, 38 (18.4%) VAs and 78 (37.7%) end-stage events occurred. Big ET-1 was positively correlated with NYHA class ( r = 0.165, P = 0.018), serum creatinine concentration (Scr; r = 0.147, P = 0.034), high-sensitivity C-reactive protein (hs-CRP; r = 0.217, P = 0.002), Lg NT-pro BNP ( r = 0.463, P < 0.001), left ventricular end diastolic diameter (LVEDD; r = 0.234, P = 0.039) and negatively correlated with left ventricular ejection fraction (LVEF; r = -0.181, P = 0.032). Kaplan-Meier analysis showed that elevated big ET-1 was associated with increased risk of VAs and end-stage events ( P < 0.05). In multivariate Cox regression models, big ET-1 was an independent risk factor for VAs (hazard ratio (HR) = 3.477, 95% confidence interval (CI): 1.352-8.940, P = 0.010, tertile 2 vs. tertile 1; HR = 4.112, 95% CI: 1.604-10.540, P = 0.003, tertile 3 vs. tertile 1) and end-stage events (HR = 2.804, 95% CI: 1.354-5.806, P = 0.005, tertile 2 vs. tertile 1; HR = 4.652, 95% CI: 2.288-9.459, P < 0.001, tertile 3 vs. tertile 1).

CONCLUSIONS: In primary prevention ICD indication patients, plasma big ET-1 levels can predict VAs and end-stage events and may facilitate ICD-implantation risk stratification.