Association between big endothelin-1 and CHADS(2)/CHA(2)DS(2)-VASc scores in non-valvular atrial fibrillation

BACKGROUND: Endothelial function, as measured by big endothelin-1 (ET-1), has been demonstrated to be useful in predicting adverse long-term events in patients with cardiovascular disease. Nevertheless, there are little data about the association between big ET-1 and thromboembolism risk in atrial fibrillation (AF). We aimed to investigate the relationship between big ET-1 and CHADS(2)/CHA(2)DS(2)-VASc scores used for evaluating thromboembolic risk in patients with non-valvular AF. METHODS: The study population consisted of 238 consecutive AF patients (67.6% with paroxysmal AF and 32.4% with persistent AF). The patients were divided into two groups (high- or low-intermediate risk group) based on CHADS(2) and CHA(2)DS(2)-VASc scores (score ≥ 2 or < 2, respectively). Clinical, laboratory, and echocardiographic parameters were evaluated, and the CHADS(2/)CHA(2)DS(2)-VASc scores were compared between groups. The association between big ET-1 levels and CHADS(2)/CHA(2)DS(2)-VASc score was assessed. Multivariate logistic regression analysis was performed to identify independent predictors of CHADS(2)/CHA(2)DS(2)-VASc scores. RESULTS: The high CHADS(2)/CHA(2)DS(2)-VASc score group had older age, higher big ET-1 levels, and enlarged left atrial diameter than the low CHADS(2)/CHA(2)DS(2)-VASc score group (P < 0.05). Multiple logistic regression analysis revealed that big ET-1 level was an independent determinant of high CHADS(2)/CHA(2)DS(2)-VASc scores [odds ratio (OR) = 2.545 and OR = 3.816; both P < 0.05]. CONCLUSIONS: Our study indicates that in non-valvular AF, big ET-1 was significantly correlated with CHADS(2)/CHA(2)DS(2)-VASc scores and an independent predictor of high CHADS(2)/CHA(2)DS(2)-VASc scores. Big ET-1 may serve as a useful marker for risk stratification in this setting.