Cong-Xin Huang

Renmin University of China, Peping, Beijing, China

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Publications (92)110.7 Total impact

  • Tao Liu · Shao-Bo Shi · Mu Qin · Cong-Xin Huang ·
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    ABSTRACT: Dantrolene, which is primarily used to treat malignant hyperthermia, has recently been suggested for the prevention of arrhythmogenesis in various animal models. In this study, the effects of dantrolene treatment on electrophysiological properties and ventricular arrhythmias (VAs) in rats with chronic β-adrenergic receptor (β-AR) activation were investigated. Rats were randomized to treatment with saline (control group), isoproterenol (ISO; ISO group), or ISO + dantrolene (ID group) for 2 weeks. An electrophysiological study was performed to assess action potential duration restitution (APDR) and induce action potential duration (APD) alternans or VA in vitro. The protein levels of Cav1.2, sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2a), and ryanodine receptor 2 (RyR2) were detected by Western blot. Compared with the control group, chronic administration of ISO significantly increased APD, the maximum slope (Smax) of APDR curve, and the spatial dispersions of Smax and APD (all P < .01), and all effects were attenuated by dantrolene treatment (all P < .05). Additionally, chronic ISO administration significantly reduced the protein levels of SERCA2 and RyR2, but increased the Cav1.2 protein expression (all P < .05). However, compared with the ISO group, dantrolene treatment preserved SERCA2a and RyR2 protein levels and decreased Cav1.2 protein levels in the ID group (all P < .05). The intracellular Ca(2+) ([Ca(2+)]i) levels measured by incubating isolated cardiomyocytes with Fluo-3/alveolar macrophages were significantly increased in the ISO group compared with the control group (P < .01). Dantrolene treatment markedly reduced the rise of [Ca(2+)]i levels caused by chronic administration of ISO (P < .05). Dantrolene treatment also prevented the reductions in the APD alternans and VA thresholds induced by chronic ISO stimulation (all P < .05). These data suggest that dantrolene stabilizes ventricular electrophysiological characteristics and increases the expression of key sarcoplasmic reticulum calcium cycling proteins to reduce vulnerability to VA in rats with chronic β-AR activation. © The Author(s) 2015.
    Journal of Cardiovascular Pharmacology and Therapeutics 01/2015; 20(4). DOI:10.1177/1074248414568194 · 2.09 Impact Factor
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    Ming-Jie Yuan · He Huang · Cong-Xin Huang ·
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    ABSTRACT: The gastrointestinal hormone ghrelin has important cardiovascular protective effects, however, its specific mechanisms are not yet completely understood. Recent studies have shown that the ghrelin receptor, growth hormone secretagogue receptor type 1a (GHSR-1a), regulates cell proliferation, apoptosis and inflammation-related signaling pathways. In human aortic endothelial cells, ghrelin activates NO production through AMP-activated protein kinase (AMPK) and Akt activation, and these effects can be blocked by knockdown of GHSR-1a. Obese mice have been found to exhibit an increased GHSR-1a content and expression in the heart, associated with an increase in phosphatidylinositol 3-kinase (PI3K) content and an increase AKT content and phosphorylation. Furthermore, GHSR-1a expression was observed to be increased in heart failure after myocardial infarction (MI) in rats. Given such complexity in GHSR-1a signaling and crosstalk with the AMPK and PI3K/Akt signaling pathways, both of which are well-known factors involved in cardiac remodeling after MI, we speculate that GHSR-1a signaling may play a regulatory role in cardiac protection and hope to identify new drugs targets. However, to date, no direct association between GHSR-1a and cardiac remodeling has been found. Therefore, further studies are required.
    Oncology letters 09/2014; 8(3):969-971. DOI:10.3892/ol.2014.2245 · 1.55 Impact Factor
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    Ming-Jie Yuan · He Huang · Li Quan · Yan-Hong Tang · Xi Wang · Hong Jiang · Cong-Xin Huang ·
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    ABSTRACT: Ghrelin is a novel growth hormone-releasing peptide, which has been shown to exert beneficial effects on cardiac function and ventricular remodeling. The present study aimed to investigate the expression of ghrelin and the growth hormone (GH) secretagogue receptor 1a (GHSR-1a), and the association with cardiac remodeling in rats with myocardial infarction (MI). Twenty-four hours after ligation of the anterior descending artery (LAD), adult male Sprague-Dawley rats were randomized to 3 d, 7 d and 28 d group. Sham animals underwent thoracotomy and pericardiotomy, but not LAD ligation. Expression of both ghrelin and GHSR-1a was assessed by means of immunohistochemistry and real-time PCR. Plasma ghrelin levels were measured by ELISA kit. In addition, cardiac remodeling was assessed by Echocardiographic and haemodynamic measurements. Plasma and cardiac expression of ghrelin decreased on days 3, 7 and 28 compared with the sham group (P < 0.05). In contrast the GHSR-1a mRNA levels increased during the same days (P < 0.05). Decreased positive immunoreaction for ghrelin and increased positive GHSR-1a was also observed in infarcted heart. Interestingly, plasma ghrelin correlated negatively with left ventricular end-diastolic pressure(r = -0.59, P = 0.002) and left ventricular end-diastloic dimension (r = -0.73, P < 0.01). The ghrelin system may play an important role regulating cardiac remodeling after MI and present as a potential significant target for pharmacological modulation and treating cardiac remodeling.
    Regulatory Peptides 06/2014; 192. DOI:10.1016/j.regpep.2014.07.001 · 1.83 Impact Factor
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    ABSTRACT: To investigate the effect of temperature on hospital admission among patients with chronic systolic heart failure (CSHF). Data regarding in-hospital patients with CSHF were gathered from 12 hospitals in Hubei province, between 2000 and 2010. Patients with a history of congenital heart disease and the history of cancer from this series, were excluded. Chi-square (χ(2)) tests and t tests were used for descriptive analysis. Univariate and multivariate logistic regression methods were performed to determinate the risk of hospital admission of every month to compare with the previous one. We used 2-tailed 95% confidence interval (CI), and tests with P < 0.01 to consider the significant levels, statistically. We also used the SPSS 13.0 for Windows, release 15, 2006 (SPSS Inc, Chicago, Ill) for data analyses. (1) 48 964 patients were enrolled in the present study. The numbers of admission increased 18.71%, 13.84%, -21.90%, -34.62%, -21.97%, -3.81%, -2.04%, 10.13%, -17.13%, -0.85%, 21.54% and 42.70% from January to December when compared to the average number of admission. (2) The odds ratios (ORs) (95% CI, P values) of hospital admission in January, February and December were 1.09 (0.96 - 1.23, 0.54), 0.98 (0.84 - 1.10, 0.46) and 0.96 (0.84 - 1.08, 0.59), respectively in females which did not show any significant differences when compared to the number in August. However the ratios were 0.61 (0.54 - 0.69, < 0.01), 0.80 (0.68 - 0.92, < 0.01) and 0.73 (0.64 - 0.83, < 0.01), respectively, in males that showed significant differences when, compared to the figures in August. (3) The OR of admission increased more when temperature got lower for patients with coronary artery disease, hypertension heart disease or rheumatic heart disease, but not with dilated cardiomyopathy. (4) The OR of admission showed a different impact on patients with different occupation, along with the change of temperature. Low or high temperature did not seem to have different effects on the OR of admission in patients who were free-lanced or unemployed. Temperature seemed to have significant effects on the risk of admission, which related to gender, etiology or occupation.
    Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 05/2013; 34(1):67-70.
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    Zhe Li · Qing-Yan Zhao · He Huang · Bo Yang · Hong Jiang · Cong-Xin Huang ·
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    ABSTRACT: Purpose: Cholinergic nerve plays an important role in the induction and maintenance of atrial fibrillation (AF). Cholinergic innervation at supraventricular tissues is considered to be the histological basis and intervention-associated target site for the arrhythmia; however, the distribution of cholinergic nerve in supraventricular tissues has not been clearly studied. In this study, we investigated the cholinergic nerve innervation in canine supraventricular regions of hearts. Methods: We performed histological and immunohistochemical staining on canine tissues of left atrial appendage (LAA), right atrial appendage (RAA), left atrium (LA), right atrium (RA), atrial septum (AS), crista terminalis (CT), pulmonary vein (PV), and super vena cava (SVC) using hematoxylin and eosin (H&E) and antibodies to choline acetyltransferase. Results: Normal canine cardiovascular histological structures were shown from H&E staining. Cholinergic nerve densities at LAA and RAA were significantly higher than LA, which was higher than RA, but no significant difference was observed between LAA and RAA. Furthermore, RA was significantly higher than AS, CT, PV, and SVC and there were no significant differences among the latter four. Conclusion: The heterogeneity of different densities of cholinergic nerve innervation of canine supraventricular regions establishes the histological basis of cholinergic nerve-mediated pathological conditions.
    Journal of Cardiology 02/2013; 61(3-4). DOI:10.1016/j.jjcc.2012.12.003 · 2.78 Impact Factor
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    ABSTRACT: Non-valvular atrial fibrillation is associated with an increased risk of ischemic stroke; however, the appropriate intensity of anticoagulation therapy for Chinese patients has not been determined. The purpose of this study was to compare the safety and the efficacy of standard-intensity warfarin therapy, low-intensity warfarin therapy, and aspirin therapy for the prevention of ischemic events in Chinese patients with non-valvular atrial fibrillation (NVAF). A total of 786 patients from 75 Chinese hospitals were enrolled in this study and randomized into three therapy groups: standard-intensity warfarin (international normalized ratio (INR) 2.1 to 2.5) group, low-intensity warfarin (INR 1.6 to 2.0) group and aspirin (200 mg per day) group. All patients were evaluated by physicians at 1, 3, 6, 9, 12, 15, 18, 21 and 24 months after randomization to obtain a patient questionnaire, physical examination and related laboratory tests. The annual event rates of ischemic stroke, transient ischemic attack (TIA) or systemic thromboembolism were 2.6%, 3.1% and 6.9% in the standard-intensity warfarin, low-intensity warfarin and aspirin groups, respectively (P = 0.027). Thromboembolic event rates in both warfarin groups were significantly lower than that in the aspirin group (P = 0.018, P = 0.044), and there was no significant difference between the two warfarin groups. Severe hemorrhagic events occurred in 15 patients, 7 (2.6%) in the standard-intensity warfarin group, 7 (2.4%) in the low-intensity warfarin group and 1 (0.4%) in the aspirin group. The severe hemorrhagic event rates in the warfarin groups were higher than that in the aspirin group, but the difference did not reach statistical significance (P = 0.101). The mild hemorrhagic and total hemorrhagic event rates in the warfarin groups (whether in the standard-intensity warfarin group or low-intensity warfarin group) were much higher than that in the aspirin group with the annual event rates of total hemorrhages of 10.2%, 7.6% and 2.2%, respectively, in the 3 groups (P = 0.001). Furthermore, there was no significant difference in all cause mortality among the three study groups. In Chinese patients with NVAF, the warfarin therapy (INR 1.6 - 2.5) for the prevention of thromboembolic events was superior to aspirin.
    Chinese medical journal 12/2012; 125(24):4355-60. DOI:10.3760/cma.j.issn.0366-6999.2012.24.007 · 1.05 Impact Factor
  • Sheng-Bo Yu · Wei Hu · Qing-Yan Zhao · Mu Qin · He Huang · Hong-Ying Cui · Cong-Xin Huang ·
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    ABSTRACT: The effects of anxiety and depression on the recurrence of persistent atrial fibrillation (AF) after circumferential pulmonary vein ablation (CPVA) are not clear. Whether CPVA can alleviate the anxiety and depression symptoms of persistent AF patients is unknown. One hundred and sixty-four patients with persistent AF, of which 43 treated with CPVA (CPVA group) and 103 treated with anti-arrhythmics drugs (medicine group), were enrolled. The Zung Self-Rating Anxiety Scale (SAS), and Zung Self-Rating Depression Scale (SDS) were assessed before and 12 months after treatment in all patients. The scores of SAS (40.33 ± 7.90 vs. 49.76 ± 9.52, P < 0.01) and SDS (42.33 ± 8.73 vs. 48.17 ± 8.77, P < 0.01) decreased 12 months after CPVA. Over 12 months follow-up, AF relapsed in 17 patients in CPVA group. Compared with the data in the recurrent group (17 patients), the scores of SAS and SDS were significantly lower in the non-recurrent group (26 patients) at baseline. The results of multivariate Logistic regression analysis showed normal scores of SAS and SDS were the independent risk factors of AF recurrence after CPVA. Anxiety and depression increase the recurrence risk of persistent AF after CPVA. CPVA can ameliorate the anxiety and depression symptoms in patients with persistent AF.
    Chinese medical journal 12/2012; 125(24):4368-72. DOI:10.1111/j.1540-8167.2012.02436.x · 1.05 Impact Factor
  • Zhe Li · He Huang · Bo Yang · Hong Jiang · Guo-Feng Gao · Blaise Z Peterson · Cong-Xin Huang ·
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    ABSTRACT: The anomalous mole fraction effect (AMFE) is an important indicator of ion-ion interactions in the pore of voltage-gated Ca2+ channels (VGCCs). The residues at position 1144 that differ in several classes of VGCCs are important to the permeation of the pore. Phe-1144 (F, CaV1) was substituted with glycine (G, CaV2) and lysine (K, CaV3) and the effects of mutation on the voltage and concentration dependency of AMFE were observed. Whole-cell currents were recorded in external solutions with Ca2+ and Ba2+ at the indicated ratios with a total divalent cation concentration of 2, 10 or 20 mM, at holding potentials from -80 to -20 mV. Results showed the ratio of Ba2+ to Ca2+ currents determined at 2 mM to be different from that determined under higher concentrations for wild-type channels but this ratio was not different when tail currents were evoked at different potentials. AMFE was greatest at relatively positive potentials (-20 mV) and when the total divalent cation concentrations were kept low (2 mM). AMFE was attenuated for F/G while it was accentuated for F/K compared with wild-type, respectively. The results demonstrated that glycine and lysine substitutions of Phe-1144 affect AMFE through different mechanisms. Additionally, residues at position 1144 were shown to be major determinates of channel permeation of several classes of VGCCs.
    Molecular Medicine Reports 11/2012; 7(2). DOI:10.3892/mmr.2012.1210 · 1.55 Impact Factor
  • Xin-Hua Wang · Cong-Xin Huang · Qian Wang · Ruo-Gu Li · Ying-Jia Xu · Xu Liu · Wei-Yi Fang · Yi-Qing Yang ·
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    ABSTRACT: Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is associated with significantly increased morbidity and mortality. Cumulative evidence highlights the importance of genetic defects in the pathogenesis of AF. However, AF is of remarkable heterogeneity and the genetic determinants of AF in a vast majority of patients remain illusive. In this study, the coding exons and splice junctions of the GATA5 gene, which encodes a zinc-finger transcription factor essential for normal cardiogenesis, were sequenced in 118 unrelated patients with lone AF. The available relatives of the index patient carrying an identified mutation and 200 unrelated ethnically-matched healthy individuals used as controls were genotyped. The functional effect of the mutant GATA5 was characterized in contrast to its wild-type counterpart using a luciferase reporter assay system. As a result, a novel heterozygous GATA5 mutation, p.W200G, was identified in a family with AF inherited as an autosomal dominant trait. The mutation was absent in 200 control individuals and the altered amino acid was completely conserved evolutionarily across species. Functional analysis showed that the mutation of GATA5 was associated with a significantly decreased transcriptional activity. These findings provide novel insight into the molecular mechanism involved in AF, suggesting potential implications for the early prophylaxis and gene-specific therapy of AF.
    International Journal of Molecular Medicine 11/2012; 31(1). DOI:10.3892/ijmm.2012.1189 · 2.09 Impact Factor
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    ABSTRACT: To explore the effects of renal sympathetic denervation on inducibility of atrial fibrillation (AF) during rapid atrial pacing. Thirteen dogs were selected and divided into control group (n = 7) and renal artery ablation group (RAA) (n = 6). In the control group, the animals were subjected to atrial pacing at 800 beats/min for 7 hours. And atrial effective refractory period (AERP) and induced AF were measured hourly during non-pacing. In the RAA group, after each renal artery ablation, the procedures of pacing and electrophysiological measurement were nearly the same as those in the control group. Blood was collected before and after pacing to measure the levels of rennin, angiotensin AngII (AngII) and aldosterone. There was a persistent decrease in AERP in both groups. However, after a 7-hour pacing, induced number of times and duration of AF were higher in the control group than those in the RAA group. The plasma concentrations of rennin and aldosterone increased significantly after 7-hour rapid pacing in the control group (rennin: (120 ± 31) to (185 ± 104) pg/ml, P < 0.01, aldosterone: (288 ± 43) to (370 ± 110) pg/ml, P = 0.01). No significant difference existed in the levels of AngII at pre- and post-pacing in the control group ((160 ± 48) to (189 ± 164) pg/ml, P = 0.23). The levels of rennin and aldosterone showed a decreasing trend in the RAA group. But there was no statistical significance. Episodes of AF during short-time rapid atrial pacing may be decreased by renal sympathetic denervation. This effect is probably related with the decreased activity of RAAS.
    Zhonghua yi xue za zhi 10/2012; 92(40):2868-71. DOI:10.3760/cma.j.issn.0376-2491.2012.40.018
  • Ming-Jie Yuan · He-Huang · Hong-Yao Hu · Li-Quan · Hong-Jiang · Cong-Xin Huang ·
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    ABSTRACT: Ghrelin has a protective role in a rat model of myocardial infarction (MI), but the underlying mechanism is not clear. Here, we investigated the effects of ghrelin treatment on angiogenesis in an experimental rat MI model. Adult male Sprague-Dawley rats were subjected to MI by ligating the anterior descending coronary artery. The rats were then treated with a subcutaneous injection of ghrelin (100μg/kg) or saline (control group) for 4weeks. Sham animals underwent thoracotomy and pericardiotomy, but not LAD ligation. At 28days after ligation, the ghrelin treatment group showed a higher density of α-SMA positive vessels than the saline treatment MI group in myocardial infarct (6±2.1/mm(2) vs 4±1.8/mm(2), P<0.05) and peri-infarct zones (25±9.5/mm(2) vs 15±5.7/mm(2), P<0.05). RT-PCR and western-blot analyses showed that ghrelin significantly increased vascular endothelial growth factor (VEGF) expression in the peri-infarct zone compared with the control group. Moreover, there was a two-fold increase of Bcl-2 and a 3.5-fold reduction of the Bax protein in the ghrelin-treated MI group compared to the saline treatment MI group. Taken together, ghrelin could induce angiogenesis in rats after MI, the process that may be associated with the enhancement of VEGF and an anti-apoptosis effect.
    Regulatory Peptides 09/2012; 179(1-3):39-42. DOI:10.1016/j.regpep.2012.08.013 · 1.83 Impact Factor
  • Tao Liu · Mu Qin · He Hu · He Huang · Cong-Xin Huang ·
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    ABSTRACT: Objective: To determine effects of activating protein kinase C (PKC) on ventricular action potential duration restitution (APDR) and Burst stimulus induced arrhythmia in Langendorff-perfused rabbit hearts. Methods: Male rabbits were equally divided into three groups randomly: control group (Tyrode's solution perfusion), PKC agonist phorbol-12-myristate-13-acetate (PMA, 100 nmol/L) group and PKC inhibitor bisindolylmaleimide (BIM, 500 nmol/L) group. Thirty minutes after perfusion, the monophasic action potential (MAP) and effective refractory period (ERP) were determined in right basal ventricle (RB), right apex (RA), left basal ventricle (LB) and left apex (LA) of all the animals, and APDR curve was drawn. Burst stimulus method was used to induce ventricular arrhythmia in perfused rabbit hearts; Real-time PCR was used to detect the mRNA expression of PKC in four different areas of ventricle. Results: Compared with the control group, the ERP, 90% of monophasic action potential duration (MAPD(90)) and ERP/MAPD(90) were significantly shortened (all P < 0.01), the max slopes (S(max)) of APDR curve were significantly steeper (RB: 1.22 ± 0.23 vs. 0.65 ± 0.19; RA: 2.99 ± 0.29 vs. 1.02 ± 0.18; LB: 1.84 ± 0.21 vs. 0.85 ± 0.12; LA: 4.02 ± 0.32 vs.1.12 ± 0.23, all P < 0.01) and the incidences of ventricular arrhythmia were significantly increased in the PMA group. All parameters were similar between the BIM group and the control group (all P > 0.05). Conclusion: Activating PKC could enhance the max slopes of APDR curve at various ventricular areas and subsequently increase arrhythmia susceptibility in Langendorff-perfused rabbit hearts.
    Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases] 09/2012; 40(9):780-785. DOI:10.3760/cma.j.issn.0253-3758.2012.09.013
  • Zhui Yu · Teng Wang · Lin Xu · Cong-xin Huang ·
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    ABSTRACT: To investigate the effects of thyroid hormone on L-type calcium channel mRNA and L-type calcium current of atrium and ventricle. Sixteen New Zealand white rabbits were randomized into Thyroxine group (n=8) and Control group (n=8). In Throxine group, rabbits were injected intraperitoneally with L-thyroxine solution for 2 weeks (1 mg/kg·d(-1)) to induce hyperthyroidism. In Control group, rabbits were injected with the same volume of saline as for Thyroxine group. On day 15, 4 rabbits in each group were killed randomly to exam the L-type calcium current of atrium and ventricle using whole cell patch clamp; the other 4 rabbits were killed to detect the expression of L-type calcium channel mRNA using RT-PCR. The mean peak of L-type calcium current densities (pA/pF) at -10 mV was higher in Thyroxine group than in Control group (-8.59±0.68 vs. -6.54±0.49 in atrium, n=8, p<0.001; -9.24±0.67 vs. -7.06±0.21 in ventricle, n=8, p<0.001). L-calcium channel mRNA expression of both atrial myocytes and ventricular cells in Thyroxine group was significantly higher than those in Control group (p<0.05). Extrinsic thyroid hormone increased expression of L-type calcium channel mRNA and ICa,L current densities in both atrium and ventricle. These changes infer that supplement of thyroid hormone may ameliorate myocardial contraction in some special conditions such as sepsis.
    Bio-medical materials and engineering 07/2012; 22(1-3):49-55. DOI:10.3233/BME-2012-0689 · 1.09 Impact Factor
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    ABSTRACT: Anxiety appears to be more common in patients with coronary artery disease (CHD) than in the general population, and anxiety symptoms may precede onset of CHD and play an important role in development of CHD. Little is known about the prevalence of anxiety symptoms in Chinese patients with premature ventricular contractions (PVCs). Our objective was to study anxiety symptoms and potential risk factors in a Chinese population with PVCs but without structural heart disease. The Zung self-rating anxiety scale (ZSAS) was used to assess anxiety symptoms. Correlation between anxiety symptoms and socio-demographics and medical factors were analyzed by Logistic regression. Of 1144 patients with PVCs (487 males and 657 females), age (53 ± 23) years old, disease duration 1 month to 24 years, a total of 381 (33.3%) patients were categorized as having anxiety symptoms. Anxiety symptoms increased with age, low income, low education level, nationality, PVC count/24 hours, bad social support, village settlement type (P < 0.05). Multivariate Logistic regression indicated that six variables-education level, ethnic minorities, dwelling place, age, PVC count/24 hours, and social support-significantly and independently related with anxiety symptoms (P < 0.05). In the Chinese population, anxiety symptoms in subjects with PVCs were frequent. Education level, ethnic minorities, dwelling place, age, PVC count/24 hours, and social support were independent risk factors for anxiety symptoms. Further research on the relationship between PVCs and anxiety symptoms in China is necessary.
    Chinese medical journal 07/2012; 125(14):2466-71. DOI:10.3760/cma.j.issn.0366-6999.2012.14.013 · 1.05 Impact Factor
  • Teng Wang · Mu Qin · He Huang · Hong-liang Li · Cong-xin Huang ·
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    ABSTRACT: To investigate the alterations of cardiac electrophysiological properties and substantial mechanism and find the stable arrhythmia mouse model in Kunming (KM) and C57BL6/J (C57) mice. Electrocardiogram recordings were used to analyze the QT interval in vivo, and mono- phasic action potential of right and left ventricular epicardium was recorded to elicit changes of action potential duration (APD) in conventional and programmed electrical stimulation (PES). Transient outward potassium current (Ito) was recorded via whole-cell patch-clamp technique in single right and left epicardial myocytes. QT interval was prolonged in KM mice relative to C57 mice (62.51±4.47 ms vs. 52.59±4.85 ms, P<0.05) The APD at 50% repolarization of the left ventricular epicardium (18.60±0.91 ms vs. 12.90±0.35 ms), and APDs at 50% (17.31±6.05 ms vs. 12.00±3.24 ms) and 70% repolarization (36.13±5.32 ms vs. 21.95±8.06 ms) of the right ventricular epicardium in KM mice were more sensitive to PES-induced ventricular tachycardia (25%, 3 of 12 hearts), and especially to Burst-induced ventricular tachycardia (50%, 6 of 12 hearts)compared with C57 mice, which were 20% (2 of 10 hearts) and 30% (3 of 10 hearts) respectively. Ito densities both in the left and right ventricular epicardial myocytes from KM mice were significantly decreased compared with C57 mice, respectively (all P<0.01). Our data showed that KM mice with the prolonged QT interval and APD are vulnerabilities to ventricular arrhythmia, which are attributed to lower Ito densities in ventricular myocytes obtained from KM mice than that from C57 mice.
    Chinese Medical Sciences Journal 07/2012; 27(2):80-7.
  • Ming-Jie Yuan · He Huang · Cong-Xin Huang ·
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    ABSTRACT: Sudden cardiac death (SCD) is a major cause of morbidity and mortality in patients with coronary artery diseases and myocardial infarction (MI). Sympathetic stimulation and sympathetic neural remodeling are important in the generation of SCD in diseased heart. The balance of nerve growth factor (NGF) and semaphoring 3A determines the sympathetic innervation patterning. Recently studies showed that P75 neurotrophin receptor (P75 NTR) is the main receptor for NGF mediates sympathetic hyperinnervation in the heart, and also interacts with semaphoring 3A. Sympathetic axons lacking P75 NTR are more sensitive to semaphoring 3A in vitro than control neurons, resulting in decreased sympathetic innervation in the left ventricular subendocardium. P75 NTR(-/-) mice had increased sympathetic heterogeneity and more spontaneous ventricular arrhythmias. Based on current studies, we present a hypothesis that P75 NTR plays an important regulatory role in sudden cardiac after myocardial infarction and hope to find new therapeutic target for SCD.
    Medical Hypotheses 06/2012; 79(3):361-2. DOI:10.1016/j.mehy.2012.05.035 · 1.07 Impact Factor
  • Tao Liu · Mu Qin · Zhen Chen · He Hu · He Huang · Cong-xin Huang ·
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    ABSTRACT: To observe the action potential duration restitution (APDR) change and potential association with ventricular arrhythmia (VA) in Langendorff-perfused chronic heart failure rabbit hearts. Male rabbits were randomly divided into two groups: control (CTL, n=15) group and chronic heart failure (CHF, n=15) group. CHF was induced by injecting isoproterenol (300 µg×kg(-1) ×d(-1)) for 14 days. Four weeks later, cardiac function and structure change of both groups were assessed by echocardiography. In the whole Langendorff-perfused hearts, the monophasic action potential (MAP) and the effective refractory period (ERP) were recorded from left anterior basal ventricle, left anterior free wall, left anterior apex and left posterior basal ventricle, left posterior free wall and left posterior apex, the APD curves were also constructed in both groups; at the six sites of every isolated heart, the programmed electrical stimulation and burst pacing were used to induce action potential duration (APD) alternans and VA, respectively. Left ventricular ejection was reduced and end-dimension was enlarged in rabbits of CHF group. Compared with the same sites of CTL group, the 90% of MAP duration (MAPD90), the ERP, the max slope (Smax) of APDR curves, the pacing cycle length of inducing the APD alternans and the VAs were significantly increased (all P<0.05) in CHF group; the spatial dispersions of MAPD90, ERP and Smax of APDR curves in CHF group were also greater than in CTL group (all P<0.05). The ventricular APD alternans might be linked with occurrence of the VA in CHF rabbits. Increase of the Smax from APDR curves and the spatial dispersions of Smax in this CHF model might facilitate the development of ventricular arrhythmia.
    Zhonghua xin xue guan bing za zhi [Chinese journal of cardiovascular diseases] 06/2012; 40(6):467-72. DOI:10.3760/cma.j.issn.0253-3758.2012.06.003
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    ABSTRACT: The purpose of this study is to investigate the mechanism and the effectiveness of ablation of atrial tachycardia (AT) recurring after atrial fibrillation (AF) ablation in patients with rheumatic valvular disease (RVD) and mitral valve prosthesis. Twenty-eight consecutive patients with RVD and mitral valve prosthesis and a 1:2 matched control group (n = 56) without RVD underwent reablation for recurrent AT after catheter ablation of long-standing persistent AF. Macro- or localized reentrant ATs were identified in 47 (87 %) of 54 ATs from RVD group and in 65 (78.3 %) of 83 ATs from control. There were more average ATs per patient in the RVD group than in the control (1.9 ± 0.6 vs.1.5 ± 0.6, P = 0.002). The proportion of patients having ≥2 ATs was significantly higher in the RVD group than in the control (78.6 vs.41.1 %, P = 0.001). In the RVD group, ATs were successfully ablated in 44 (81.5 %) of 54 ATs and terminated in 18 (64.3 %) of 28 patients. In the control, ATs were successfully ablated in 72 (86.7 %) of 83 ATs and terminated in 45 (80.4 %) of 56 patients, P = 0.54 and 0.10, respectively. After a mean follow-up of 13 months, 16 patients (57.1 %) from the RVD group and 45 patients (80.4 %) from the control were free of further recurrence, P = 0.02. Macro- or localized reentries were the predominant type of recurrent AT after long-standing persistent AF ablation in both the RVD and the control groups. Compared with patients without RVD, patients with RVD had more average number of ATs and had higher probability of further recurrence despite the similar acute effectiveness of reablation.
    Journal of Interventional Cardiac Electrophysiology 05/2012; 35(1):45-56. DOI:10.1007/s10840-012-9678-1 · 1.58 Impact Factor
  • Qing-Yan Zhao · Sheng-Bo Yu · He Huang · Hong-Ying Cui · Mu Qin · Ting Huang · Cong-Xin Huang ·
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    ABSTRACT: Studies have shown that increased levels of serum uric acid (SUA) are associated with atrial fibrillation (AF). However, less is known about the prognostic value of SUA levels for AF in patients with chronic heart failure (CHF). The aim of the study was to examine the prognostic value of SUA levels for AF in patients with CHF. Sixteen thousand six hundred and eighty-one patients diagnosed with CHF from 12 hospitals were analyzed. Patients were categorized into AF group and non-AF group, death group, and survival group according to the results of the patients' medical records and follow-up. Univariate and multivariate Cox proportional hazards analyses were performed to examine the risk of AF. The sensitivity and specificity of SUA level in predicting the prognosis were examined by multivariate Cox models and receiver operating characteristic (ROC) curves. The results of univariate predictors in overall patients showed that the higher SUA level was associated with AF. SUA level (HR, 1.084; 95%CI, 1.017 - 1.144; P < 0.001), diuretics (HR, 1.549; 95%CI, 1.246 - 1.854; P < 0.001), and New York Heart Association (NYHA) (HR, 1.237; 95%CI, 1.168 - 1.306; P < 0.001) function class were the independent risk factors for AF. The sensitivity and specificity of the models were 29.6% and 83.8% respectively for predicting AF. When SUA level was added to these models, it remained significant (Wald c(2), 1494.88; P < 0.001 for AF); 58.8% (95%CI, 57.7% - 60.0%) of the observed results were concordant with the separate model. Higher SUA level is associated strongly with AF in patients with CHF. SUA level can increase the sensitivity and specificity in predicting AF.
    Chinese medical journal 05/2012; 125(10):1708-12. DOI:10.3760/cma.j.issn.0366-6999.2012.10.006 · 1.05 Impact Factor
  • Sheng-bo Yu · Qing-yan Zhao · He Huang · Dong-e Chen · Hong-ying Cui · Mu Qin · Cong-xin Huang ·
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    ABSTRACT: Researchers still do not reach the consensus on the incidence, characters and the prognostic value of pericardial effusion (PE) in patients with chronic heart failure (CHF). This study is to investigate the incidence, characters and the prognostic value of pericardial effusion (PE) in patients with CHF. One thousand one hundred and eighty-nine patients, with a diagnosis of CHF consecutively admitted to three centers, were enrolled. M-mode echocardiography was used to determine the presence or absence of PE and to semi-quantify it. The 118 patients with PE and 472 without PE were followed up. The relationship between the PE and other parameters and the prognostic value of PE for CHF were analyzed by univariate and multivariate analyses. After following up, 550 patients were analyzed, of which 226 were dead. The incidence of PE was 9.92%. Moderate PE was the most common which account 90.68% (107/118). The 6.78% of the patients (8/118) had small while only 2.54% (3/118) had large one. The systolic blood pressure (OR=1.04, 95%CI (1.01-1.07), P=0.08), left ventricular ejection fraction (LVEF) (OR=1.09, 95%CI (1.02-1.15), P=0.06), and main pulmonary artery diameter (MPAD) (OR=1.51, 95%CI (1.24-1.85), P<0.001) were the independent predictors of PE. The glomerular filtration rate (GFR) (OR=1.013, 95%CI (1.005-1.026), P=0.02), systolic blood pressure (OR=1.02, 95%CI (1.00-1.03), P=0.015), LVEF (OR=1.08, 95%CI (1.04-1.12), P<0.001) and diabetes mellitus (OR=3.53, 95%CI (1.99-6.44), P<0.001) were determined as the independent predictors of CHF prognosis. The PE is not uncommon in CHF patients and most PE are small to moderate. PE is not related to the etiology of CHF while is strongly connected with higher systolic blood pressure, low LVEF and large MPAD. PE dose not increase the risk of death in patients with CHF.
    Chinese medical journal 03/2012; 125(5):882-7. DOI:10.1016/j.cardfail.2011.06.198 · 1.05 Impact Factor