This study was aimed to evaluate the relationship between the changes of plasma intermedin (IMD) and atrial fibrosis in hypertensive patients with atrial fibrillation. During the period from 2010 to 2011, appropriate 150 subjects of out-patients (female 50%, male 50%) were selected in West China Hospital, Sichuan University, and were divided into three groups: the hypertension-only group, the hypertension combined with paroxysmal atrial fibrillation group and the hypertension combined with persistent atrial fibrillation group. Firstly, we collected the Physical examination results and medical history records of the patients. We then performed ultrasound cardiogram and blood biochemical tests on the patients. We also detected the plasma IMD and transforming growth factor β1 (TGF-β1) using ELISA. The results showed that compared with the hypertensive group, the plasma level of IMD, TGF-β1 and left atrium director (LAD) in the hypertensive combined with atrial fibrillation group were higher significantly. Compared with the paroxymal atrial fibrillation group, the levels of IMD, TGF-β1 and LAD were higher significantly in persistent atrial fibrillation group. Analysis of correlation and partial correlation showed that IMD was positively correlated with TGF-p1 (r=0.51, P<0. 001), IMD was positively correlated with LAD(r=0.59, P< 0.001), and TGF-β1 was positively correlated with LAD (r = 0.57, P < 0.001). The results suggest that IMD might suppress the pathophysiological process of atrial fibrillation.
Atrial Fibrillation ; physiopathology ; Female ; Humans ; Hypertension ; physiopathology ; Male ; Peptide Hormones ; blood ; Transforming Growth Factor beta1 ; blood

OBJECTIVETo investigate the influence of persistent rapid atrial pacing on the levels of connexin 43 (Cx43) and type III collagen in pulmonary vein and atrium in a canine model.

METHODSSixteen mongrel dogs were divided into rapid atrial pacing (RAP) group (n = 8) and normal control group (n = 8) randomly. In the RAP group, atrial pacing was performed with a rate of 400 bpm for 10 weeks to establish atrial fibrillation model. The tissues of left superior pulmonary vein (LSPV), left atrial free wall (LAFW) and right atrial appendage (RAA) were collected from each dogs. The levels of Cx43 and type III collagen were measured in each tissue.

RESULTSTen weeks later, persistent atrial fibrillation was induced in all dogs in RAP group. The level of Cx43 in RAP group was higher than that in normal control group (LSPV: 3370.91 +/- 275.11 vs 1405.82 +/- 90.38, P < 0.05; LAFW: 2448.68 +/- 272.10 vs 1467.12 +/- 147.93, P < 0.05, RAA: 2331.96 +/- 199.61 vs 1288.27 +/- 216.22, P < 0.05). The level of Cx43 in LSPV was higher than that in LAFW and RAA in RAP group, whereas the difference between LAFW and RAA was not significant in RAP group. The quantities of type III collagen in RAP group were higher than those in normal control group (LSPV: 3301.97 +/- 309.70 vs 1404.56 +/- 178.02, P < 0.05; LAFW: 2477.86 +/- 190.43 vs 1479.20 +/- 187.17, P < 0.05; RAA: 2045.92 +/- 139.43 vs 1417.07 +/- 139.43, P < 0.05). The quantities of type III collagen in LSPV was higher than those in LAFW and RAA in RAP group.

CONCLUSIONSPersistent rapid atrial pacing could increase the levels of Cx43 and type III collagen in pulmonary vein and atrium in a canine model of atrial fibrillation. The levels of Cx43 and type III collagen in pulmonary vein were higher than those in atrium. This findings indicated that pulmonary vein may be a crucial regions in maintaining atrial fibrillation.

Animals ; Atrial Fibrillation ; metabolism ; physiopathology ; Cardiac Pacing, Artificial ; methods ; Collagen Type III ; blood ; Connexin 43 ; blood ; Disease Models, Animal ; Dogs ; Female ; Male ; Pulmonary Veins ; metabolism ; physiopathology

Atrial fibrillation may occur in patients with a variety of cardiovascular or chronic disease as well as in normal subjects. Many authors reported that atrial fibrillation occurs in patients with thyrotoxicosis. It is reported that a low serum thyrotrophin concentration in an asymptomatic person with normal serum thyroid hormone concentrations can be a independent risk factor for developing atrial fibrillation. But we focused on the significance of serum thyroid stimulating hormone (TSH) in the euthyroid patient with atrial fibrillation whose serum level of T3, T4, fT4, and even TSH were absolutely within normal range. On our results, there was no significant differences in age, sexual distribution, and left ventricular ejection fraction between the patients group of paroxysmal and chronic persistent atrial fibrillation (p> 0.05), but there was larger left atrial dimension (LAD) and more cases of rheumatic heart disease in the chronic persistent atrial fibrillation group and there was more cases of lone atrial fibrillation in the paroxysmal atrial fibrillation group (p< 0.05). There was no significant differences in serum levels of T3, T4, fT4 between paroxysmal and chronic persistent atrial fibrillation, but significantly lower serum TSH was found in patients with paroxysmal atrial fibrillation (p< 0.001), and these findings were more significant after the control of hemodynamic change (p< 0.001 vs p< 0.05). The discriminant value in serum TSH between the paroxysmal and chronic atrial fibrillation group was 1.568U/mL with about 76% of predictive power. There was significantly lower serum TSH in paroxysmal atrial fibrillation in all age groups (p< 0.05). There was a significantly higher prevalence of cerebral thromboembolic events in chronic persistent (27.7%) and disease-associated (15.0% atrial fibrillation than in the paroxysmal (3.3%) and lone (4.5%) atrial fibrillation group (p< 0.001). Therefore, we suggest that serum TSH below the serum concentration of 1.5U/mL can be a risk factor for developing atrial fibrillation when the serum level of T3, T4, fT4, and even TSH were within absolutely normal range.
Adult ; Aged ; Aged, 80 and over ; Analysis of Variance ; Atrial Fibrillation/*blood/physiopathology ; Chi-Square Distribution ; Female ; Human ; Male ; Middle Age ; Thyroid Function Tests ; Thyroid Gland/*physiopathology ; Thyrotropin/*blood

PURPOSE: Recently, mitochondrial DNA 4977bp deletion (mtDNA4977-mut), a somatic mutation related to oxidative stress, has been shown to be associated with atrial fibrillation (AF). We hypothesized that patient age, as well as electroanatomical characteristics of fibrillating left atrial (LA), vary depending on the presence of mtDNA4977-mut in peripheral blood among patients with non-valvular AF. MATERIALS AND METHODS: Analyzing clinical and electroanatomical characteristics, we investigated the presence of the mtDNA4977-mut in peripheral blood of 212 patients (51.1+/-13.2 years old, 83.5% male) undergoing catheter ablation for non-valvular AF, as well as 212 age-matched control subjects. RESULTS: The overall frequency of peripheral blood mtDNA4977-mut in patients with AF and controls was not significantly different (24.5% vs. 19.3%, p=0.197). When the AF patient group was stratified according to age, mtDNA4977-mut was more common (47.4% vs. 20.0%, p=0.019) in AF patients older than 65 years than their age-matched controls. Among AF patients, those with mtDNA4977-mut were older (58.1+/-11.9 years old vs. 48.8+/-11.9 years old, p<0.001). AF patients positive for the mtDNA mutation had greater LA dimension (p=0.014), higher mitral inflow peak velocity (E)/diastolic mitral annular velocity (Em) ratio (p<0.001), as well as lower endocardial voltage (p=0.035), and slower conduction velocity (p=0.048) in the posterior LA than those without the mutation. In multivariate analysis, E/Em ratio was found to be significantly associated with the presence of mtDNA4977-mut in peripheral blood. CONCLUSION: mtDNA4977-mut, an age-related somatic mutation detected in the peripheral blood, is associated with advanced age and electro-anatomical remodeling of the atrium in non-valvular AF.
Adult ; Aged ; Atrial Fibrillation/blood/*genetics/*physiopathology ; Atrial Remodeling/*genetics ; Base Pairing/*genetics ; Case-Control Studies ; DNA, Mitochondrial/*blood/*genetics ; Female ; Heart Atria/pathology/physiopathology ; Humans ; Kaplan-Meier Estimate ; Logistic Models ; Male ; Middle Aged ; Mutation Rate ; Phenotype ; Sequence Deletion/*genetics

OBJECTIVETo investigate the effect of atrial fibrillation on the accuracy of parameters monitored by transpulmonary thermodilution method.

METHODSTotally 12 patients from emergency intensive care unit with paroxysmal atrial fibrillation were enrolled. The hemodynamic parameters such as heart rate, mean arterial pressure, cardiac index, systemic vascular resistance index, intrathoracic blood volume index, and extravascular lung water index were monitored by transpulmonary thermodilution method before paroxysmal atrial fibrillation and during atrial fibrillation, the number of B-lines was detected by lung ultrasonography before and during paroxysmal atrial fibrillation. The changes of all the parameters were analyzed.

RESULTSWhen the paroxysmal atrial fibrillation happened, the heart rate increased significantly [(123.3±20.0) beat/min vs. (98.9±12.3) beat/min, P=0.006]; the mean arterial pressure [(86.9±10.2) mmHg vs. (93.0±12.5) mmHg, P=0.058], cardiac index [(2.82±0.62) L/(min·m(2)) vs. (3.31±1.02) L/(min·m(2)), P=0.058] and systemic vascular resistance index [(2254±947) dyn·s·cm(-5)·m(2) vs. (2302±828) dyn·s·cm(-5)·m(2), P=0.351] had no obvious change; however, the intrathoracic blood volume index significantly increased [(1333±90) ml/m(2) vs. (937±111) ml/m(2), P<0.001]; extravascular lung water index also increased significantly [(16.1±1.1) ml/kg vs. (6.5±1.9) ml/kg, P<0.001]. No significant difference was found in the number of B-lines detected by lung ultrasonography before and during atrial fibrillation (10.0±4.2 vs. 9.4±4.4, P=0.180).

CONCLUSIONBoth intrathoracic blood volume and extravascular lung water monitored by transpulmonary thermodilution method were overvalued during paroxysmal atrial fibrillation, which may mislead the clinical judgment and decision-making.

Atrial Fibrillation ; physiopathology ; Blood Pressure ; Blood Volume ; Cardiac Output ; Extravascular Lung Water ; Heart Rate ; Hemodynamics ; Humans ; Intensive Care Units ; Thermodilution ; Vascular Resistance

We present a case of pulmonary vein (PV) stenosis after radio-frequency (RF) ablation, in which a hemodynamic change in the pulmonary artery was similar to that of congenital PV atresia on time-resolved contrast-enhanced magnetic resonance angiography (TR-MRA). A 48-year-old man underwent RF ablation due to atrial fibrillation. The patient subsequently complained of hemoptysis, dyspnea on exertion, and right chest pain. Right PV stenosis after catheter ablation was diagnosed through chest computed tomography and lung perfusion scan. Pulmonary TR-MRA revealed the pulmonary artery via systemic arterial collaterals and draining systemic collateral veins. On a velocity-encoded cine image, the flow direction of the right pulmonary artery was reversed in the diastolic phase and the left pulmonary artery demonstrated continuous forward flow throughout the cardiac cycle. These hemodynamic changes were similar to those seen in congenital unilateral PV atresia.
Atrial Fibrillation/*surgery ; Blood Flow Velocity ; Catheter Ablation/*adverse effects ; Constriction, Pathologic/*etiology/pathology ; Contrast Media ; Humans ; *Magnetic Resonance Angiography ; Male ; Middle Aged ; Pulmonary Artery/pathology/physiopathology ; *Pulmonary Circulation ; Pulmonary Veins/*pathology/physiopathology

OBJECTIVETo investigate the effect of cilazapril on endothelial cell function and fibrinolysis system in the canine atrial fibrillation (AF) models.

METHODSAll canines were divided into three groups: (1) Control group, without atrial pacing; (2) Atrial pacing group, in which atrial fibrillation was established by rapid atrial pacing at 400 bpm for 6 weeks; (3) Atrial pacing together with cilazapril group, in which cilazapril was given before and after atrial pacing. Nitric oxide (NO) of atrial endocardium was measured with NO-specific microelectrode. The expression of plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (tPA) protein in atrium was determined by Western Blot analysis and immunohistochemical staining. Plasma levels of von Willebrand Factor (vWF), PAI-1 and tPA were analyzed by enzyme-linked immunoadsorbent assay.

RESULTSNO production from atrial endocardium was significantly increased in atrial pacing together with cilazapril group than atrial pacing group [(42.6 +/- 9.9) nmol/L vs (23.4 +/- 5.8) nmol/L, P < 0.05], whereas the plasma levels of vWF were decreased [(75.4 +/- 12.8)% vs (125.9 +/- 20.6)%, P < 0.05]. Compared to controls, the expression of atrium tPA protein in atrial pacing together with cilazapril group was significantly upregulated (4052 +/- 857 vs 1936 +/- 421, P < 0.05) and PAI-1 protein was downregulated (2487 +/- 542 vs 3164 +/- 827, P < 0.05). Cilazapril also significantly increased tPA antigen and decreased PAI-1 antigen in plasma.

CONCLUSIONCilazapril can favorably improve endothelial function and resume the balance of fibrinolysis system in AF, which might be of beneficial to hypercoagulated state in AF.

Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Animals ; Atrial Fibrillation ; blood ; drug therapy ; physiopathology ; Cilazapril ; pharmacology ; Disease Models, Animal ; Dogs ; Endothelial Cells ; drug effects ; physiology ; Female ; Fibrinolysis ; drug effects ; Immunohistochemistry ; Male ; Plasminogen Activator Inhibitor 1 ; analysis ; Tissue Plasminogen Activator ; analysis

Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; Animals ; Atrial Fibrillation ; blood ; drug therapy ; physiopathology ; Cilazapril ; pharmacology ; Dogs ; Echocardiography ; Endothelial Cells ; drug effects ; physiology ; Fibrinolysis ; drug effects ; Nitric Oxide ; biosynthesis ; Plasminogen Activator Inhibitor 1 ; analysis ; Tissue Plasminogen Activator ; analysis