Associations of big endothelin-1 and C-reactive protein in atrial fibrillation

Relationship between red blood cell distribution width levels and atrial fibrillation in hypertensive patients

Background

Information on the relationship between red blood cell distribution width (RDW) and atrial fibrillation (AF) in patients with essential hypertension are scarce. The study aimed to assess the relationship between AF and RDW in hypertensive patients.

Methods

We enrolled 432 hypertensive patients, including 350 AF patients and 82 patients as controls. Patients' demographic, clinical, laboratory and echocardiographic characteristics were recorded. The AF patients were further divided into the persistent and paroxysmal AF subgroups. Electrocardiograms were monitored to identify the cardiac rhythm during blood sampling, and based on the rhythm, the paroxysmal AF group was categorized into the presence (with AF rhythm during blood sampling) and absence (with sinus rhythm during blood sampling) groups.

Results

The AF group had elevated RDW levels than the controls (12.7% ± 0.8% vs. 12.4% ± 0.7%, P = 0.002), and the persistent AF subgroup had higher RDW levels than the paroxysmal AF subgroup (12.9% ± 0.8% vs. 12.6% ± 0.8%, P = 0.007). Furthermore, in the paroxysmal AF group, the presence group had higher RDW levels than the absence group (13.0% ± 0.6% vs. 12.5% ± 0.9%, P = 0.001). There was no significant difference in RDW levels between the persistent AF subgroup and presence group of the paroxysmal AF subgroup (P = 0.533) and between the absence group of the paroxysmal AF subgroup and control group (P = 0.262). In multivariate regression analysis, in hypertensive patients, the presence of AF rhythm is an independent predictor for increased RDW concentration (P = 0.001).

Conclusions

The RDW may be associated with the presence of AF rhythm, which implies the importance of maintaining the sinus rhythm in hypertensive patients.

Analysis of Endothelin-1 Concentrations in Individuals with Periodontitis

Endothelin 1 (ET-1) has been shown to have a key role in homeostasis and function of endothelium and maybe fundamental in the relationship between coronary heart disease (CHD) and periodontitis. In this trial, we assessed the influence on serum and salivary ET-1 levels of gingival health, CHD, periodontitis, or a combination of periodontitis-CHD. Clinical and periodontal parameters, were collected from periodontitis patients (n = 34), CHD patients (n = 34), periodontitis + CHD patients (n = 34), and from healthy patients (n = 34) together with saliva and serum samples. The median concentrations of salivary and serum ET-1 were significantly higher in the CHD patients [serum: 1.4(1.1-1.6) pg/ml; saliva 1.2 (0.9-1.6) µmol/g, p < 0.01] and in the periodontitis + CHD patients [serum: 1.7 (1.2-21.8) pg/ml; salivary 1.4(1-1.6) µmol/g, p < 0.001] respect to periodontitis and control patients. Through a univariate regression analysis, c-reactive protein (CRP) and CHD (both p < 0.001) and periodontitis (p = 0.029) were statistically correlated with ET-1 in serum. The multivariate regression analysis demonstrated that only CRP was the statistically predictor of ET-1 in serum(p < 0.001). The multivariate regression analysis in saliva demonstrated that, regarding ET-1 levels the only predictor were CRP (p < 0.001) and total cholesterol (p = 0.042). The present study evidenced that subjects with CHD and periodontitis plus CHD had higher serum and salivary levels of ET-1 compared to subjects with periodontitis and healthy controls. Moreover, only CRP remained a major predictor of increased ET-1 concentrations in both serum and saliva.

Dynamics of Soluble Thrombomodulin and Circulating miRNAs in Patients with Atrial Fibrillation Undergoing Radiofrequency Catheter Ablation

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world and has a high risk of thromboembolism. The most effective approach, catheter ablation, requires evaluation by electrocardiography. The aim of our study was to investigate novel clinical markers that predict restoration of sinus rhythm (SR) after catheter ablation. Seventy-eight consecutive patients with AF underwent catheter ablation and were separated into 2 groups: restored SR and recurrent AF. The levels of 4 blood proteins (serum or plasma) and 3 mature microRNAs (miRNAs) and their primary miRNAs (pri-miRNAs) in serum were measured before and after ablation, and the associations between each parameter were analyzed statistically. Soluble thrombomodulin (s-TM) and plasminogen activator inhibitor-1 (PAI-1) levels increased above baseline after ablation in both the restored SR (s-TM 11.55 [2.92] vs 13.75 [3.38], P < .001; PAI-1 25.74 [15.25] vs 37.79 [19.56], P < .001) and recurrent AF (s-TM 10.28 [2.78] vs 11.67 [3.37], P < .001; PAI-1 26.16 [15.70] vs 40.74 [22.55], P < .001) groups. Levels of C-reactive protein and asymmetric dimethylarginine were not significantly changed. Pri-miR-126 levels significantly decreased after ablation in the recurrent AF group, but the other miRNAs and pri-miRNAs did not. The measurement of s-TM and pri-miR-126 in blood was a useful tool to reflect the condition of AF patients with catheter ablation.

The Expression of BNP, ET-1, and TGF-β1 in Myocardium of Rats with Ventricular Arrhythmias

Ventricular arrhythmia (VA) is a major component of sudden cardiac death (SCD). To investigate the expression of brain natriuretic peptide (BNP), endothelin-1 (ET-1), and transforming growth factor-beta 1 (TGF-β1) during VA, we established a rat model of VA induced by BaCl₂ solution through a microinjector pump. PD142893 (ET-1 receptor blocker) and SB431542 (TGF-β1 receptor type I blocker) were used to explore the effect of ET-1 and TGF-β1 on BNP expression in the myocardium after VA. BNP, ET-1, and TGF-β1 in rat myocardium were assayed by western blot and immunohistochemical staining for proteins, and real-time quantitative polymerase chain reaction for mRNAs. We found increased expression of BNP and ET-1 in rat myocardium that was associated with the duration of VA. However, TGF-β1 protein expression remained unchanged. Such early increases in BNP and ET-1 may be attributed to fatal arrhythmias associated with SCD, suggesting these may be novel biomarkers of this disease. After intraperitoneal injection of PD142893 and SB431542, respectively, BNP was downregulated in the myocardium of the left ventricle; however, this was abrogated by co-application of the two inhibitors. These results suggested that both ET-1 and TGF-β1, by specifically binding to their receptors, might be involved in the myocardial synthesis of BNP during VA in vivo.

Association between big endothelin-1 and CHADS2/CHA2DS2-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 CHADS₂/CHA₂DS₂-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 CHADS₂ and CHA₂DS₂-VASc scores (score ≥ 2 or < 2, respectively). Clinical, laboratory, and echocardiographic parameters were evaluated, and the CHADS_2/CHA₂DS₂-VASc scores were compared between groups. The association between big ET-1 levels and CHADS₂/CHA₂DS₂-VASc score was assessed. Multivariate logistic regression analysis was performed to identify independent predictors of CHADS₂/CHA₂DS₂-VASc scores.

RESULTS

The high CHADS₂/CHA₂DS₂-VASc score group had older age, higher big ET-1 levels, and enlarged left atrial diameter than the low CHADS₂/CHA₂DS₂-VASc score group (P < 0.05). Multiple logistic regression analysis revealed that big ET-1 level was an independent determinant of high CHADS₂/CHA₂DS₂-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 CHADS₂/CHA₂DS₂-VASc scores and an independent predictor of high CHADS₂/CHA₂DS₂-VASc scores. Big ET-1 may serve as a useful marker for risk stratification in this setting.

Plasma big endothelin-1 predicts new-onset atrial fibrillation after surgical septal myectomy in patients with hypertrophic cardiomyopathy

Background

Postoperative atrial fibrillation (POAF) is a common complication in patients with obstructive hypertrophic cardiomyopathy (HOCM) who undergo surgical myectomy. POAF is associated with poor outcome. The role of plasma big endothelin-1 level in predicting atrial fibrillation after surgical septal myectomy in HOCM patients has not well been studied.

Methods

A total of 118 patients with HOCM who underwent surgical septal myectomy were recruited in this study. Plasma big endothelin-1 level was measured. The heart rhythm was continuously monitored during hospital stay. Preoperative, intraoperative, and postoperative variables were collected.

Results

POAF developed among 26 of the 118 patients (22%) in this study. Compared with those without POAF, patients with POAF were significantly older (53.5 ± 10.6 vs. 47.3 ± 13.6 years, P = 0.033), more likely to undergo mitral valve surgery (38.5% vs. 18.5%, P = 0.032), and had higher plasma big endothelin-1 levels (0.41 ± 0.19 vs. 0.27 ± 0.14 pmol/l, P = 0.001), longer hospital stay (9.1 ± 3.7 vs. 7.5 ± 2.8 days, P = 0.022), larger preoperative left atria (48.0 ± 5.2 vs. 44.1 ± 5.9 mm; P = 0.003). In the receiver operating characteristic curve analysis, the area under the curve for big endothelin-1 was 0.734 (95% CI, 0.634 to 0.834, P<0.001). In multivariate logistic regression analysis, preoperative big endothelin-1 level (OR 100.7, 95%CI: 5.0–2020.0, P = 0.003) and left atrial diameter (OR 1.106, 95%CI: 1.015–1.205, P = 0.022) were independent predictors of POAF.

Conclusion

Elevated preoperative plasma big endothelin-1 level is an independent predictor of POAF in HOCM patients undergoing surgical septal myectomy.