Qina Zhou

Effects of Renal Sympathetic Denervation on Post-Myocardial Infarction Cardiac Remodeling in Rats

Objective To investigate the therapeutic effects of renal denervation (RD) on post- myocardial infarction (MI) cardiac remodeling in rats, the most optimal time for intervention and the sustainability of these effects. Methods One hundred SPF male Wistar rats were randomly assigned to N group (Normal, n = 10), MI group(MI, n = 20),RD group (RD, n = 10), RD3+MI (MI three days after RD, n = 20), MI1+RD (RD one day after MI, n = 20), MI7+RD (RD seven days after MI, n = 20). MI was produced through thoracotomic ligation of the anterior descending artery. RD was performed through laparotomic stripping of the renal arteriovenous adventitial sympathetic nerve. Left ventricular function, hemodynamics, plasma BNP, urine volume, urine sodium excretion and other indicators were measured four weeks after MI. Results (1) The left ventricular function of the MI group significantly declined (EF<40%), plasma BNP was elevated, urine output was significantly reduced, and 24-hour urine sodium excretion was significantly reduced. (2) Denervation can be achieved by surgically stripping the arteriovenous adventitia, approximately 3 mm from the abdominal aorta. (3) In rats with RD3+MI, MI1+RD and MI7+RD, compared with MI rats respectively, the LVEF was significantly improved (75±8.4%,69±3.8%,73±5.5%), hemodynamic indicators were significantly improved, plasma BNP was significantly decreased, and the urine output was significantly increased (21.3±5 ml,23.8±5.4 ml,25.2±8.7 ml). However, the urinary sodium excretion also increased but without significant difference. Conclusions RD has preventive and therapeutic effects on post-MI cardiac remodeling.These effects can be sustained for at least four weeks, but there were no significant differences between denervation procedures performed at different times in the course of illness. Cardiac function, hemodynamics, urine volume and urine sodium excretion in normal rats were not affected by RD.

A Meta‐Analysis of the Comparative Efficacy of Ablation for Atrial Fibrillation with and without Ablation of the Ganglionated Plexi

Background:  Ganglionated plexi (GP) is claimed to be potentially responsible for atrial fibrillation (AF). The efficacy and safety of GP ablation remains controversial. This meta‐analysis aimed to assess the efficacy of procedure with or without ablation of GP.

Catheter-Based Renal Sympathetic Denervation Significantly Inhibits Atrial Fibrillation Induced by Electrical Stimulation of the Left Stellate Ganglion and Rapid Atrial Pacing

Background Sympathetic activity involves the pathogenesis of atrial fibrillation (AF). Renal sympathetic denervation (RSD) decreases sympathetic renal afferent nerve activity, leading to decreased central sympathetic drive. The aim of this study was to identify the effects of RSD on AF inducibility induced by hyper-sympathetic activity in a canine model. Methods To establish a hyper-sympathetic tone canine model of AF, sixteen dogs were subjected to stimulation of left stellate ganglion (LSG) and rapid atrial pacing (RAP) for 3 hours. Then animals in the RSD group (n = 8) underwent radiofrequency ablation of the renal sympathetic nerve. The control group (n = 8) underwent the same procedure except for ablation. AF inducibility, effective refractory period (ERP), ERP dispersion, heart rate variability and plasma norepinephrine levels were measured at baseline, after stimulation and after ablation. Results LSG stimulation combined RAP significantly induced higher AF induction rate, shorter ERP, larger ERP dispersion at all sites examined and higher plasma norepinephrine levels (P<0.05 in all values), compared to baseline. The increased AF induction rate, shortened ERP, increased ERP dispersion and elevated plasma norepinephrine levels can be almost reversed by RSD, compared to the control group (P<0.05). LSG stimulation combined RAP markedly shortened RR-interval and standard deviation of all RR-intervals (SDNN), Low-frequency (LF), high-frequency (HF) and LF/HF ratio (P<0.05). These changes can be reversed by RSD, compared to the control group (P<0.05). Conclusions RSD significantly reduced AF inducibility and reversed the atrial electrophysiological changes induced by hyper-sympathetic activity.

Effects of renal denervation on the development of post-myocardial infarction heart failure and cardiac autonomic nervous system in rats

Prior studies indicated that radiofrequency renal denervation (RD)had beneficial effects on post-myocardial infarction (MI) heart failure(HF) in rats[1–3]. In this studywe aimedtoassessits effects on cardiacautonomic nervous system (CANS) which might be one of the mostimportant mechanisms of RDs therapeutic effect on post-MI HF anddetermine the best timing for RD.One hundred Wistar rats were randomly assigned intofiveexperimental groups: MI group (n = 20), RD group (n = 20),MI-1d + RD group (RD performed one day post-MI, n = 20),MI-4w + RD group (RD performed four weeks post-MI, n = 20),andNgroup(controlgroup, n = 20).MIwasproducedthroughligationof the anterior descending artery. RD was performed through strippingof the renal nerves. The experimental design and implementation wereconducted in accordance with animal welfare guidelines.Eight weeks post-MI, significant improvements were observed inboth MI-1d + RD and MI-4w + RD groups compared to the MIgroup, that include (1) improved left ventricular (LV) function andhemodynamics with increased water and sodium excretion;(2) decreased plasma and renal tissue norepinephrine levelswhile tissue norepinephrine content increased in myocardium;(3) increased β1-receptor in myocardium and improved heartratevariability;and(4)decreasedplasmarenin,angiotensinII,aldoste-rone,BNPandendothelinlevels.Moretherapeuticeffectswerefoundinthe MI-1d + RD group than the MI-4w + RD group (see Table 1 andFig. 1).Firstly, our study showed that RD attenuated the remodeling ofCANS and modulated its activities. RD leads to preservation of β1receptors content along with the β1 mRNA expression in non-infarcted cardiac tissue in this HF model (Fig. 1). This correlated withan improvement in heart function and cardiac remodeling. HRV is asensitive marker for the CANS [4]. RD led to a slower HR and higherSDNN in both intervention groups (See Table 1). The increase in SDNNindicates that cardiac sympathetic over-activation was suppressed andvagal activity was enhanced with the result of stabilizing cardiacelectrical activity, decreasing malignant arrhythmias, thereby reducingthe incidence of sudden death.Secondly, we found that RD blocked both peripheral and centralRAAS and sympathetic nervous system (SNS) at the same time. Andthis may answer the question how RD exerted effect on CANS. In ourstudy RD restores renin, angiotensin II, and aldosterone to near-normal levels. This not only explains the increase in sodium and waterexcretion, but also confirms that RD blocks renal RAAS via blockage ofthe efferent renal sympathetic nerves which is consistent with ourprevious study [2]. Studies have shown that angiotensin II not onlyactivates the central and peripheral SNS, function as part of a positivefeedback cycle between RAAS and the SNS, but also activates the localRAAS of other organs, notably the heart [5]. Our study also showedthat the plasma NE level in MI-1d + RD and MI-4w + RD groupsdecreased significantly, which reflects an overall reduction ofsympathetic activity, and especially represents reduction of centralsympathetic activity. This result maybe in part due to blockade of therenal sympathetic afferent pathway by RD. Furthermore, previousstudies have shown that during HF, the tissue NE levels of both theheart and kidney are decreased due to depletion, decreased reuptakeand increased spillover. The decrease of the tissue NE level causedfeedback activation of the central sympathetic system [6].Thus,increased tissue NE level may alleviate the activation of the centralsympathetic system, which was reflected by our data (Fig. 1).Many studies have shown that central RAAS stimulates the central

Effect of Interconnection between Cervical Vagus Trunk, Epicardial Fat Pad on Sinus Node Function, and Atrial Fibrillation

The epicardial fat pad (FP) integrates the autonomic innervation between the extrinsic and intrinsic cardiac autonomic nervous system and affects atrial electrophysiology and pathophysiology.

Impact of contact force technology on reducing the recurrence and major complications of atrial fibrillation ablation: A systematic review and meta-analysis

Contact force (CF) monitoring can be useful in accomplishing circumferential pulmonary vein (PV) isolation for atrial fibrillation (AF). This meta-analysis aimed to assess the efficacy and safety of a CF-sensing catheter in treating AF. Randomized controlled trials or non-randomized observational studies comparing AF ablation using CF-sensing or standard non-CF (NCF)-sensing catheters were identified from PubMed, EMBASE, Cochrane Library, Wanfang Data, and China National Knowledge Infrastructure (January 1, 1998–2016). A total of 19 studies were included. The primary efficacy endpoint was AF recurrence within 12 months, which significantly improved using CF-sensing catheters compared with using NCF-sensing catheters [31.1% vs. 40.5%; risk ratio (RR)=0.82; 95% confidence interval (CI), 0.73–0.93; p<0.05]. Further, the acute PV reconnection (10.1% vs. 24.2%; RR=0.45; 95% CI, 0.32–0.63; p<0.05) and incidence of major complications (1.8% vs. 3.1%; OR=0.59; 95% CI, 0.37–0.95; p<0.05) significantly improved using CF-sensing catheters compared with using NCF-sensing catheters. Procedure parameters such as procedure duration [mean difference (MD)=-28.35; 95% CI, -39.54 to -17.16; p<0.05], ablation time (MD=-3.8; 95% CI, -6.6 to -1.0; p<0.05), fluoroscopy duration (MD=-8.18; 95% CI, -14.11 to -2.24; p<0.05), and radiation dose (standard MD=-0.75; 95% CI, -1.32 to -0.18; p<0.05] significantly reduced using CF-sensing catheters. CF-sensing catheter ablation of AF can reduce the incidence of major complications and generate better outcomes compared with NCF-sensing catheters during the 12-month follow-up period.

Left atrial appendage occlusion in atrial fibrillation for stroke prevention: A systemic review

BACKGROUND Atrial fibrillation (AF) is an arrthymia characterized by increased risk of ventricle arrthymias and thromboembolism especially ischemic stroke. Most thrombus originated in the left atrial appendage, thus left atrial occlusion (LAAO) may be an effective alternative for stroke prevention in atrial fibrillation. OBJECTIVE To assess the effect and safety of left atrial occlusion for stroke prevention in atrial fibrillation. METHODS AND RESULTS We searched Pub Med, CENTRAL in The Cochrane Library, Embase, CBM-Disk, CNKI for published trials, ClinicalTrials.gov, ISI Proceedings for conference abstracts, and WHO International Clinical Trial registration Platform for ongoing studies. The search results were extracted, and then the quality of included studies was assessed. By RevMan 5.3, meta analysis was used if there was low heterogeneity. Three randomized controlled clinical trials involving 1165 participants were included (percutaneous 1114 in 2 trials, surgical 51 in 1 trial). The current data suggest that left atrial occlusion may be as efficacious as warfarin in stroke prevention (RR 0.78 [0.33, 1.84]) and mortality reduction (RR 0.68 [0.40, 1.16]) for AF. CONCLUSION In contrast to warfarin left atrial occlusion with Watchman device may have the same effectivity in stroke reduction. Surgical LAAO may also get positive outcomes compared with warfarin, but owing to the small sample size the evidence is less powerful. Total outcomes of percutaneous and surgical LAAO support this approach.

Reference values of brachial-ankle pulse wave velocity according to age and blood pressure in a central Asia population

Background Brachial-ankle pulse wave velocity (baPWV), a direct measure of aortic stiffness, has increasingly become an important assessment for cardiovascular risk. The present study established the reference and normal values of baPWV in a Central Asia population in Xinjiang, China. Methods We recruited participants from a central Asia population in Xinjiang, China. We performed multiple regression analysis to investigate the determinants of baPWV. The median and 10th-90th percentiles were calculated to establish the reference and normal values based on these categories. Results In total, 5,757 Han participants aged 15–88 years were included in the present study. Spearman correlation analysis showed that age (r = 0.587, p < 0.001) and mean blood pressure (MBP, r = 0.599, p <0.001) were the major factors influencing the values of baPWV in the reference population. Furthermore, in the multiple linear regression analysis, the standardized regression coefficients of age (0.445) and MBP (0.460) were much higher than those of body mass index, triglyceride, and glycemia (-0.054, 0.035, and 0.033, respectively). In the covariance analysis, after adjustment for age and MBP, only diabetes was the significant independent determinant of baPWV (p = 0.009). Thus, participants with diabetes were excluded from the reference value population. The reference values ranged from 14.3 to 25.2 m/s, and the normal values ranged from 13.9 to 21.2 m/s. Conclusions This is the first study that has established the reference and normal values for baPWV according to age and blood pressure in a Central Asia population.

Idiopathic premature ventricular complexes originating from the distal great cardiac vein: Clinical, cardiac and electrophysiological characteristics and catheter ablation outcome

Aims: Although catheter ablation for idiopathic ventricular arrhythmia (VA) has been generally well‐established, VA originating from the great cardiac vein (GCV) may be clinically challenging due to its epicardial origin, proximity to coronary arteries and limited accessibility. The purpose of this study was to explore its electrophysiological characteristics and identify effective mapping/ablation strategies for idiopathic premature ventricular complexes (PVCs) originating from the GCV. Materials and methods: Between January 2013 to January 2018, 12 patients (who were diagnosed with PVCs originating from the GCV) among the 305 patients with idiopathic left ventricular outflow tract tachycardia were included. The origin of the ectopy was localized by mapping, the characteristics of the electrocardiogram (ECG) were analyzed, and all the patients with PVCs originating from GCV were treated by radiofrequency catheter ablation (RFCA). The safety and efficacy of RFCA were evaluated. Key findings: The origin of the ectopy was successfully localized in GCV for all 12 patients by mapping, and access to GCV via the coronary sinus was feasible. Successful RFCA was achieved in 11 of 12 patients (91.67% acute procedural success) without perioperative complications. During a median follow‐up of 12.6 ± 6.5 months, only one patient had recurrent VA (recurrence rate: 9.1%). Significance: ECG characteristics may be helpful for identifying patients with PVCs originating from the GCV. RFCA within the coronary venous system appears to be safe and effective for these patients, and should be considered when routine RFCA from the endocardium or aortic sinus of the Valsalva is not effective.

Ethnicity and anticoagulation management of hospitalized patients with atrial fibrillation in northwest China

The therapeutic management and health challenges caused by atrial fibrillation (AF) differ between different groups. The purpose of this study was to investigate the clinical features of patients hospitalized with AF and to explore the use of anticoagulation treatments in Han and Uygur patients in Xinjiang, northwest China. Data were collected from a retrospective descriptive study involving patients hospitalized at 13 hospitals in Xinjiang, China from Jul 1, 2014 to Jun 31, 2015. Anticoagulation management was measured according to guideline-recommended risk scores. A total of 4,181 patients with AF were included (mean age 69.5 ± 11.7 years, 41.4% females; 71.5% Han, 28.5% Uygur). The prevalence of AF in Uygur individuals may occur earlier than in Han individuals (mean age 64.9 vs 71.3, P < 0.001). Most of the hospitalized patients with AF had a high risk of stroke (CHA2DS2-VASc score ≥2; 80.6% Han vs 73.7% Uygur, P < 0.05); this risk was especially high in elderly patients. In AF patients, the application of anticoagulants according to the guidelines is far from expected, and the underutilization of anticoagulants exists in both ethnic groups.