Nan Jia

Is cryoballoon ablation preferable to radiofrequency ablation for treatment of atrial fibrillation by pulmonary vein isolation? A meta-analysis.

Objective Currently radiofrequency and cryoballoon ablations are the two standard ablation systems used for catheter ablation of atrial fibrillation; however, there is no universal consensus on which ablation is the optimal choice. We therefore sought to undertake a meta-analysis with special emphases on comparing the efficacy and safety between cryoballoon and radiofrequency ablations by synthesizing published clinical trials. Methods and Results Articles were identified by searching the MEDLINE and EMBASE databases before September 2013, by reviewing the bibliographies of eligible reports, and by consulting with experts in this field. Data were extracted independently and in duplicate. There were respectively 469 and 635 patients referred for cryoballoon and radiofrequency ablations from 14 qualified clinical trials. Overall analyses indicated that cryoballoon ablation significantly reduced fluoroscopic time and total procedure time by a weighted mean of 14.13 (95% confidence interval [95% CI]: 2.82 to 25.45; P = 0.014) minutes and 29.65 (95% CI: 8.54 to 50.77; P = 0.006) minutes compared with radiofrequency ablation, respectively, whereas ablation time in cryoballoon ablation was nonsignificantly elongated by a weighted mean of 11.66 (95% CI: −10.71 to 34.04; P = 0.307) minutes. Patients referred for cryoballoon ablation had a high yet nonsignificant success rate of catheter ablation compared with cryoballoon ablation (odds ratio; 95% CI; P: 1.34; 0.53 to 3.36; 0.538), and cryoballoon ablation was also found to be associated with the relatively low risk of having recurrent atrial fibrillation (0.75; 0.3 to 1.88; 0.538) and major complications (0.46; 0.11 to 1.83; 0.269). There was strong evidence of heterogeneity and low probability of publication bias. Conclusion Our findings demonstrate greater improvement in fluoroscopic time and total procedure duration for atrial fibrillation patients referred for cryoballoon ablation than those for radiofrequency ablation.

Apocynin attenuates oxidative stress and cardiac fibrosis in angiotensin II-induced cardiac diastolic dysfunction in mice

Aim:To investigate whether apocynin, a NADPH oxidase inhibitor, produced cardioproteictive effects in Ang II-induced hypertensive mice, and to elucidate the underlying mechanisms.Methods:C57BL/6 mice were subcutaneously infused Ang II for 4 weeks to mimic cardiac remodeling and fibrosis. Concomitantly the mice were administered apocynin (100 mg·kg−1·d−1) or/and the aldosterone receptor blocker eplerenone (200 mg·kg−1·d−1) via gavage for 4 weeks. Systolic blood pressure (SBP) and heart rate were measured, and transthoracic echocardiography was performed. For in vitro study, cardiac fibroblasts were treated with Ang II (10−7 mol/L) in the presence of apocynin (10−5 mol/L) or/and eplerenone (10−5 mol/L). Immunohistochemistry and Western blotting were used to quantify the expression levels of NADPH oxidase and osteopontin (OPN) proteins in the cells.Results:Both apocynin and eplerenone significantly decreased SBP, and markedly improved diastolic dysfunction in Ang II-induced hypertensive mice, accompanied with ameliorated oxidative stress and cardiac fibrosis. In the Ang II-treated cardiac fibroblasts, the expression levels of NOX4 and OPN proteins were markedly upregulated. Both Apocynin and eplerenone significantly suppressed the increased expression levels of NOX4 and OPN proteins in the Ang II-treated cells. In all the experiments, apocynin and eplerenone produced comparable effects. Co-administration of the two agents did not produce synergic effects.Conclusion:Apocynin produces cardioproteictive effects comparable to those of eplerenone. The beneficial effects of apocynin on myocardial oxidative stress and cardiac fibrosis might be mediated partly through a pathway involving NADPH oxidase and OPN.

The relationship between five widely-evaluated variants in CDKN2A/B and CDKAL1 genes and the risk of type 2 diabetes: a meta-analysis.

The genes encoding two cyclin-dependent kinases-inhibitor-2A/B (CDKN2A/B) and 5 regulatory subunit-associated protein-like 1 (CDKAL1) have been investigated extensively in associations with type 2 diabetes; the results, however, are often irreproducible. We therefore sought to evaluate these associations by performing a meta-analysis on five widely-evaluated variants from the two genes. There were 38 studies (patients/controls: 51,940/52,234) for rs10811661, 16 studies (20,029/24,419) for rs564398 in CDKN2A/B gene, and 27 studies (28,383/47,635) for rs7756992, 26 studies (28,816/31,713) for rs7754840, 21 studies (29,260/38,400) for rs10946398 in CDKAL1 gene. Overall risk estimates for type 2 diabetes conferred by rs10811661-T, rs564398-A, rs7754840-C, rs7756992-G, and rs10946398-C alleles were 1.17 (95% CI: 1.10-1.23; P<0.0005; I(2)=83.9%), 1.1 (95% CI: 1.0-1.21; P=0.051; I(2)=88.3%), 1.24 (95% CI: 1.18-1.3; P<0.0005; I(2)=74.3%), 1.2 (95% CI: 1.11-1.3; P<0.0005; I(2)=92.0%), and 1.19 (95% CI: 1.1-1.29; P<0.0005; I(2)=90.8%), respectively. There was evident publication bias for rs564398 and rs7754840. Subgroup analyses by ethnicity showed remarkable divergences in risk estimate for rs564398 between Asians (odds ratio [OR]=1.01; 95% CI: 0.86-1.19; P=0.868) and Caucasians (OR=1.19; 95% CI: 1.03-1.35; P=0.012) (P<0.05). For all variants examined, the results of studies in retrospective design or with population-based controls were comparative with that of overall studies. In meta-regression analyses, age was found to exert a significant influence on the association between rs10811661 and type 2 diabetes (P=0.003), as well as between rs7754840 and gender (P=0.034). Taken together, our findings provide evidence for a significant contribution of CDKN2A/B gene rs10811661 and CDKAL1 gene rs7756992 and rs10946398 to type 2 diabetes.

Replication of the top 10 most significant polymorphisms from a large blood pressure genome-wide association study of northeastern Han Chinese East Asians

The replication of genome-wide significant association signals in independent populations is a practical approach for characterizing gene-disease relationships. Therefore, we sought to explore the top 10 polymorphisms from a large blood pressure genome-wide association study of northeastern Han Chinese East Asians. This was a hospital-based study involving 1009 patients with essential hypertension and 756 normotensive controls from Qiqihar city, China. Genotyping was conducted with a polymerase chain reaction-ligase detection reaction method. All polymorphisms except for rs6825911 satisfied Hardy–Weinberg equilibrium. Overall, the genotype differences between the patients and controls were significant for rs35444 (P<0.001), rs11191548 (P=0.017) and rs17249754 (P=0.017). The per-minor-allele odds ratios of rs35444, rs11191548 and rs17249754 were 0.54 (95% confidence interval (95% CI): 0.46–0.62; P<0.01), 1.23 (95% CI: 1.07–1.43; P=0.005) and 1.23 (95% CI: 1.07–1.41; P=0.004), respectively. Similarly, the carriers of minor homozygotes had a significant reduction in adjusted systolic and diastolic blood pressure for rs35444 (P<0.01) but an increase for both rs11191548 (P<0.01) and rs17249754 (P<0.04). Further application of the genetic risk score method indicated that subjects with risk scores of 8, 10 and 12–16 had 1.66-fold (95% CI: 1.01–2.72), 1.72-fold (95% CI: 1.03–2.86) and 1.97-fold (95% CI: 1.12–3.46) increases, respectively, in the odds of developing hypertension, and similar increases were also observed for blood pressure. Taken together, our findings demonstrate that although only three of the top 10 polymorphisms were successfully validated in the northeastern Han Chinese population, the genetic risk score analyses led us to more profound insights into the possible joint effects of multiple polymorphisms on hypertension risk and blood pressure variation.

Impact of Mineralocorticoid Receptor Antagonists on Changes in Cardiac Structure and Function of Left Ventricular Dysfunction

Background—A comprehensive evaluation of the benefits of mineralocorticoid receptor antagonists on cardiac remodeling is lacking. We aimed to evaluate the impact of mineralocorticoid receptor antagonists on changes in cardiac structure and function of left ventricular dysfunction. Methods and Results—Articles were identified by online searches in PubMed, EMBASE, Cochrane, and ClinicalTrials.gov databases before June 2012, by hand searches of reviews and relevant journals, and by contact with the authors. Qualified articles were restricted to randomized controlled trials. There were, respectively, 12, 4, and 3 qualified trials that randomized 572, 647, and 407 patients to spironolactone, canrenoate, and eplerenone, and 531, 655, and 395 patients to placebo or active treatment, respectively. Overall, under mineralocorticoid receptor antagonist treatment there was improvement in left ventricular ejection fraction (weighted mean difference, 2.97; 95% confidence interval [95% CI], 2.26–3.67; P<0.0005), left ventricular end-systolic and end-diastolic volume index (weighted mean difference, −5.64; 95% CI, −7.94 to −3.34; P<0.0005 and weighted mean difference, −7.46; 95% CI, −11.63 to −3.3; P<0.0005), serum amino-terminal peptide of procollagen type-III (weighted mean difference, −1.12; 95% CI, −1.49 to −0.74; P<0.0005), B-type natriuretic peptide (weighted mean difference, −67.06; 95% CI, −91.24 to −42.88; P<0.0005), peak velocities of early mitral inflow (E; weighted mean difference, −9.57; 95% CI, −12.98 to −6.17; P<0.0005), and E wave deceleration time (weighted mean difference, 7.08; 95% CI, 4.07–10.09; P<0.0005). There was low probability of heterogeneity and publication bias. Conclusions—Our findings demonstrate that mineralocorticoid receptor antagonist treatment may exert beneficial effects on the reversal of cardiac remodeling and improvement of left ventricular function.

Impact of Mineralocorticoid Receptor Antagonists on Changes in Cardiac Structure and Function of Left Ventricular Dysfunction A Meta-analysis of Randomized Controlled Trials

Background—A comprehensive evaluation of the benefits of mineralocorticoid receptor antagonists on cardiac remodeling is lacking. We aimed to evaluate the impact of mineralocorticoid receptor antagonists on changes in cardiac structure and function of left ventricular dysfunction. Methods and Results—Articles were identified by online searches in PubMed, EMBASE, Cochrane, and ClinicalTrials.gov databases before June 2012, by hand searches of reviews and relevant journals, and by contact with the authors. Qualified articles were restricted to randomized controlled trials. There were, respectively, 12, 4, and 3 qualified trials that randomized 572, 647, and 407 patients to spironolactone, canrenoate, and eplerenone, and 531, 655, and 395 patients to placebo or active treatment, respectively. Overall, under mineralocorticoid receptor antagonist treatment there was improvement in left ventricular ejection fraction (weighted mean difference, 2.97; 95% confidence interval [95% CI], 2.26–3.67; P<0.0005), left ventricular end-systolic and end-diastolic volume index (weighted mean difference, −5.64; 95% CI, −7.94 to −3.34; P<0.0005 and weighted mean difference, −7.46; 95% CI, −11.63 to −3.3; P<0.0005), serum amino-terminal peptide of procollagen type-III (weighted mean difference, −1.12; 95% CI, −1.49 to −0.74; P<0.0005), B-type natriuretic peptide (weighted mean difference, −67.06; 95% CI, −91.24 to −42.88; P<0.0005), peak velocities of early mitral inflow (E; weighted mean difference, −9.57; 95% CI, −12.98 to −6.17; P<0.0005), and E wave deceleration time (weighted mean difference, 7.08; 95% CI, 4.07–10.09; P<0.0005). There was low probability of heterogeneity and publication bias. Conclusions—Our findings demonstrate that mineralocorticoid receptor antagonist treatment may exert beneficial effects on the reversal of cardiac remodeling and improvement of left ventricular function.

Synergistic association of DNA repair relevant gene polymorphisms with the risk of coronary artery disease in northeastern Han Chinese

Evidence is mounting suggesting that DNA damage is implicated in the development and progression of atherosclerosis. To yield more information, we focused on six well-characterized polymorphisms from four DNA repair-relevant candidate genes, viz. XRCC1 (rs1799782 and rs25487), XRCC3 (rs861539), MTHFR (rs1801133 and rs4846049), and NQO1 (rs1800566), to identify and characterize their potential gene-to-gene interactions in susceptibility to coronary artery disease (CAD) in Han Chinese. This was a hospital-based case-control study involving 1142 patients diagnosed with CAD and 1106 age- and gender-matched controls. All participants were angiographically confirmed. Risk estimates were expressed as odds ratio (OR) and 95% confidence interval (95% CI). All six examined polymorphisms met Hardy-Weinberg equilibrium. Overall there were significant differences in the genotype/allele distributions of MTHFR gene rs1801133 and rs4846049 (both P ≤ 0.005), and in the genotype distributions of XRCC1 gene rs1799782 (P = 0.002) between patients and controls. The adjusted risk of having CAD was more evident for rs1799782 (OR = 1.53; 95% CI: 1.16-2.02; P = 0.003), rs1801133 (OR = 1.54; 95% CI: 1.22-1.94; P < 0.001), and rs4846049 (OR = 1.74; 95% CI: 1.13-2.69; P = 0.013) under the recessive model. Interaction analyses indicated that the overall best multifactor dimensionality reduction (MDR) model included rs4846049, rs1801133, and rs1799782, and this model had a maximal testing accuracy of 0.6885 and a cross-validation consistency of 10 out of 10 (P = 0.0030). Further interaction entropy graph bore out the validity of this MDR model. Taken together, our findings demonstrate a contributory role of genetic defects in XRCC1 and MTHFR genes, both individually and interactively, in the development of CAD in Han Chinese.

Left Radial Access Is Preferable to Right Radial Access for the Diagnostic or Interventional Coronary Procedures: A Meta-Analysis Involving 22 Randomized Clinical Trials and 10287 Patients

Objective The transradial approach has been used extensively for both diagnostic and interventional coronary procedures; however, there is no universal consensus hitherto on the optimal choice of radial access from either the left or the right artery. We therefore sought to meta-analyze available randomized clinical trials to compare the left with the right radial access for the diagnostic or interventional coronary procedures. Methods and Results Four electronic databases including the PubMed, EMBASE, Wanfang, and CNKI were searched up to April 2013. In total, there were 22 qualified randomized trials involving 5317 and 4970 patients assigned to the left and the right radial accesses, respectively. Data were extracted independently by two investigators. Analyses of the full data set indicated significant reductions in fluoroscopy time (seconds) (weighted mean difference; 95% confidence interval; P: −36.18; −53.28 to −18.53; <0.0005) and contrast use (mL) (−2.88; −5.41 to −0.34; 0.026) in patients with the left radial access compared to those with the right radial access, and there was strong evidence of heterogeneity but low probability of publication bias. The failure rate of radial access from the left was relatively lower than that from the right (odds ratio: 0.83; 95% confidence interval: 0.68−1.01; P = 0.064). Further in meta-regression analyses, body mass index was found to be a potential source of heterogeneity for both fluoroscopy time (regression coefficient: 35.85; P = 0.025) and catheter number (regression coefficient: 0.35; P = 0.018). Conclusions Our findings demonstrate that left radial access is preferable to right radial access in terms of fluoroscopy time and contrast use for the diagnostic or interventional coronary procedures. The import of this study lies in its great shock to the concept of convenient radial access from the right artery.

Association of Four Genetic Polymorphisms of AGER and Its Circulating Forms with Coronary Artery Disease: A Meta-Analysis

Background Considerable efforts have been devoted to evaluating the association of the receptor for advanced glycation end-products (gene AGER and protein: RAGE) genetic variants to coronary artery disease (CAD); the results, however, are often irreproducible. To generate more information, we sought to explore four common polymorphisms of AGER and its circulating forms associated with the risk of CAD via a meta-analysis. Methodology/Principal Findings Articles were identified by searching PubMed, EMBASE, Wanfang and CNKI databases before March 2013. Qualified articles had case-control designs and investigated AGER four polymorphisms (T-429C, T-374A, Gly82Ser, G1704A) or circulating soluble RAGE (sRAGE) or endogenous secretory RAGE (esRAGE) levels associated with CAD. Twenty-seven articles involving 39 independent groups fulfilled the predefined criteria. Overall, no significance was observed for all examined polymorphisms under allelic and dominant models. When restricting groups to CAD patients with diabetes mellitus or renal disease, deviations of risk estimates from the unity were stronger than overall estimates for all polymorphisms except for G1704A due to limited available studies. For example, under dominant model, having -429C allele increased the odds of developing CAD in diabetic patients by 1.22-fold (95% confidence interval (95% CI) 0.99–1.51; P = 0.06; I 2 = 6.7%) compared with that of overall estimate of 1.15-fold (95% CI: 0.97–1.36; P = 0.111; I 2 = 18.0%). Circulating sRAGE levels were non-significantly lower in CAD patients than in controls, whereas this reduction was totally and significantly reversed in CAD patients with diabetes mellitus (weighted mean difference: 185.71 pg/ml; 95% CI: 106.82 to 264.61 pg/ml). Circulating esRAGE levels were remarkably lower in CAD patients, as well as in subgroups with or without diabetes mellitus and without renal disease. Conclusions Our findings demonstrated that association of AGER genetic polymorphisms with CAD was potentiated in patients with diabetes mellitus or renal disease. Practically, circulating esRAGE might be a powerful negative predictor for the development of CAD.

The Contributory Role of Angiotensin Receptor-Like 1 Gene Multiple Polymorphisms in Hypertension among Northeastern Han Chinese

Background and Objective Via direct sequencing, we have recently identified six common polymorphisms in angiotensin receptor-like 1 (AGTRL1) gene, and found only two polymorphisms were significantly associated with hypertension in a family-based analysis on 1,015 southern Han Chinese. Extending our previous work and considering the ubiquity of epistasis in determining disease susceptibility, we, in this study, sought to explore the potential interaction of AGTRL1 gene six polymorphisms with hypertension in a large northeastern Han Chinese population. Methods and Results This was a case-control study involving 1,009 sporadic hypertensive patients and 756 normotensive controls. Data were analyzed by Haplo.Stats and multifactor dimensionality reduction (MDR) softwares. There were no deviations from Hardy-Weinberg equilibrium for all polymorphisms. The genotypes and alleles of rs7119675 and rs11544374 differed significantly between the two groups (P<0.0005), even after the Bonferroni correction. Under three genetic models, significant association was consistently observed for rs7119675 and rs11544374, and this association was independent of confounding factors. Taking rs7119375 as an example, the odds of having hypertension was 2.46 (95% confidence interval (95% CI): 2.06–2.94), 2.82 (95% CI: 2.29–3.46) and 3.97 (95% CI: 2.37–6.64) under additive, dominant and recessive models (P<0.001), respectively, whereas the adjusted risk estimates were slightly attenuated but still significant. The frequencies of most derived haplotypes differed significantly between patients and controls. Haplotype-phenotype analyses indicated marginal association for triglyceride (PSim = 0.011) and total cholesterol (PSim = 0.025) in patients and for triglyceride in controls (PSim = 0.023). The overall best MDR model included rs11544374, rs7119375 and rs948847 with the maximal testing accuracy of 0.737 and cross-validation consistency of 10 out of 10 (P<0.0001). Further interaction entropy graph suggested that the interaction of rs7119375 with rs11544374 and rs948847 was strongly antagonized. Conclusions Our findings demonstrate that AGTRL1 genetic polymorphisms might contribute to the development of hypertension independently and/or through complex interaction.