Value of the HFA-PEFF diagnostic algorithms for heart failure with preserved ejection fraction to the inflammatory myopathy population.

OBJECTIVES: The HFA-PEFF score has been validated to hold great diagnostic and prognostic utility for heart failure with preserved ejection fraction (HFpEF). Idiopathic inflammatory myopathy (IIM) is recognized as one of the potential etiologies underlying HFpEF. Here, we intended to investigate the real prevalence of HFpEF in IIM via the HFA-PEFF score and explore the prognostic value of this score. METHODS: Two hundred twenty IIM patients were enrolled for assessment. The cohort was divided into low, intermediate and high tertiles of the HFA-PEFF score. Spearman's correlation analysis was used to explore the association between the score and disease activity. Chi-square test was applied to investigate the distribution discrepancy of HFA-PEFF tertiles among patients with different myositis-specific antibodies (MSAs) or myositis-associated antibodies (MAAs). Univariate and multivariate ordinal regression analyses were performed to screen risk factors for high HFA-PEFF scores. Survival curves were obtained using the Kaplan-Meier method and log-rank tests. RESULTS: In total, 79 (35.9%), 107 (48.6%) and 34 (15.5%) patients were rated low, intermediate and high probability of HFpEF, respectively. The HFA-PEFF score correlated well with disease activity. Patients with positive AMA-M2 scored higher in the HFA-PEFF score (p = 0.011). During follow-up, patients with positive AMA-M2 or anti-SRP antibody developed an inclination towards concentric hypertrophy on echocardiography. Additionally, palpitation symptom, AMA-M2 positivity and elevated serum levels of LDH, cTnI were independent risk factors for high HFA-PEFF scores. Finally, a high-tertile HFA-PEFF score was related to lower overall survival rate (p < 0.001). Patients with positive AMA-M2 had poorer outcomes (p = 0.002). CONCLUSION: HFpEF was prevailing in IIM patients according to the HFA-PEFF score. The HFA-PEFF score correlated well with disease activity and held significant prognostic value. Patients with AMA-M2 antibody were prone to have poor outcomes.

Hyperuricemia Increases the Risk of Atrial Fibrillation: A Systematic Review and Meta-Analysis.

Association between hyperuricemia (HUA) and atrial fibrillation (AF) remains unclear. We reviewed clinical evidence and aimed to determine whether hyperuricemia leads to a high risk of atrial fibrillation. Most studies were identified through databases online. Keywords used in literature search were hyperuricemia, atrial fibrillation, metabolic disorder, endocrine disorder, or uric acid. Three studies were provided by the authors. Literature search was performed without any data or language restriction. Observational studies, including cohort studies and cross-sectional studies, were used. Study type should be clearly defined. Cross-sectional studies should clearly introduce the sources of epidemiological data. Studies were excluded if with too many complications unrelated to AF enrolled. Data were independently extracted by three individuals. Data synthesis was conducted by R version 4.1.2. Prevalence of atrial fibrillation was the main outcome. Results of meta-analysis were presented as risk ratio (RR) for different prevalence of AF between individuals with and without HUA. All data included were obtained after follow-up work is completed. Data from 608,810 participants showed that patients with hyperuricemia were easier to suffer from atrial fibrillation (RR, 2.42; 95% CI, 1.24-3.03). And the meta-regressions suggested growth of linear proportion between the ratio of current drinkers and hyperuricemia (QM = 41.0069, P < 0.001). Subgroup analyses demonstrated consistent results in different countries. And design of the observational studies brought heterogeneity, but no uncertainties. Patients with hyperuricemia were easier to suffer from atrial fibrillation. Treatment of hyperuricemia or gout may bring potential benefits for AF patients.

Percutaneous Ventricular Restoration Prevents Left Ventricular Remodeling Post Myocardial Infarction: One-Year Evaluation of the Heartech First-in-man Study.

BACKGROUND: This is first-in-man investigation of an implantable Heartech left ventricular partitioning device (LVPD) therapy for chronic heart failure (HF) after a myocardial infarction. METHODS AND RESULTS: Initially, 16 patients were chosen from 3 cardiac centers within China. All patients were treated with percutaneous ventricular restoration involving the Heartech LVPD implantation. Major adverse cardiovascular and cerebrovascular events were documented. Functional status, echocardiograph evaluation, European five-dimensional health scale, 6-minute walk test before the procedure and at postoperative follow-ups were recorded. We demonstrated successful implantation and device function with a success rate of 93.75%. One patient suffered a fatal myocardial infarction within the 12 ± 1 month follow-up. However, other patients did not report any major adverse cardiovascular and cerebrovascular events at their 12 ± 1 month follow-ups. After the operation, the average left ventricular end-systolic volume index decreased dramatically (66.00 mL/m2, interquartile range [IQR] 63.00-89.00 mL/m2 vs 48.00 mL/m2, IQR 32.25-68.25 mL/m2, P = .001), along with the left ventricular end-diastolic volume index (105.00 mL/m2, IQR 90.00-130.00 mL/m2 vs 76.50 mL/m2, IQR 57.75-120.25 mL/m2, P = .002). The left ventricular ejection fraction (35.00%, IQR 27.00-38.00% vs 42.50%, IQR 34.75-50.25%, P = .003), 6-minute walk test (383.13 ± 108.70 m vs 491.17 ± 118.44 m, P = .01), and European five-dimensional health scale (65.93 ± 11.25 vs 82.50 ± 5.44, P < .001), in turn, improved significantly. CONCLUSIONS: In our study, the Heartech LVPD was demonstrated as both safe and effective in reducing LV volume, enhancing LV function after implantation. These results remain constant at least till the 12 month follow-up. (Trial Registration: NCT02938637.).

Heartech® left ventricular partitioning device improves left ventricular systolic function of patients with chronic heart failure post-myocardial infarction at 1-year follow-up.

OBJECTIVES: This study presents 1-year follow-up data of echocardiographic outcomes in patients who received the Heartech® left ventricular (LV) partitioning device (LVPD) (Xinrui Medical Equipment Co. Ltd., Shanghai, China). BACKGROUND: Our first-in-man study of the Heartech® LVPD confirmed its safety and efficacy in patients with chronic heart failure (HF) post-myocardial infarction (MI) 1 month post-implantation. This subsequent study reports the echocardiographic outcomes of these patients at 1 year of follow-up. METHODS: Fifteen patients with HF post-MI from three cardiac intervention centers in China were successfully implanted with the Heartech® LVPD via percutaneous ventricular restoration procedures. Echocardiographic parameters-including LV systolic function, diastolic function, two-dimensional speckle-tracking analysis, and right ventricular systolic function-were obtained before device implantation and at 1 month and 1 year postoperatively. RESULTS: There was no deterioration of LV diastolic function, specific strain parameters, or right ventricular function at 1 year. Relative to the echocardiographic parameters recorded before the procedure, the LV ejection fraction (32.47 ± 6.98% vs. 42.5 ± 7.41%; p = .001) was significantly improved at 1 year, while the LV end-diastolic volume index (106.29 ± 28.01 vs. 83.30 ± 31.71; p = .005) and end-systolic volume index were significantly reduced (72.47 ± 22.77 vs. 50.00 ± 19.70; p = .001). CONCLUSIONS: One-year echocardiographic follow-up results confirmed that no deterioration of LV diastolic function or specific strain parameters was observed and LV systolic function was significantly improved in patients with HF post-MI who were implanted with the Heartech® LVPD.

Outcomes of Spironolactone Withdrawal in Dilated Cardiomyopathy With Improved Ejection Fraction.

Background: The feasibility of spironolactone withdrawal in dilated cardiomyopathy patients with improved ejection fraction remains unknown. This study sought to determine whether spironolactone can be withdrawn safely in this circumstance. Methods: Consecutive patients with idiopathic dilated cardiomyopathy and prescribed spironolactone at discharge were included in this prospective, observational cohort using the Risk Evaluation and Management in Heart Failure Trial (NCT02998788) database. Those patients who experienced an absolute left ventricular ejection fraction (LVEF) improvement ≥10% and a second measurement of LVEF >40% would choose whether to continue spironolactone therapy and be included in final analysis. The primary endpoint was dilated cardiomyopathy relapse within 12 months, defined as a more than 10% reduction in LVEF, a 15% or greater increase in LVESVi, a 2-fold rise in NT-proBNP, or clinical signs of heart failure. Results: Seventy patients achieved an ejection fraction improvement and were included in the final analysis, of whom 30 chose to continue spironolactone and 40 decided to withdraw. In primary endpoint analysis, 23 (58%) patients from the withdrawal group and 4 (13%) patients from the continuation group relapsed (relative risk for relapse: 4.31; 95% CI: 1.67-11.11; p < 0.001). Patients from the withdrawal group experienced more symptom aggravation than the continuation group. No secondary safety endpoint was recorded. Improvements in cardiac structure parameters were no longer observed after spironolactone withdrawal, while improvements persisted in continuation group. Conclusions: Most dilated cardiomyopathy patients with improved ejection fraction will relapse after spironolactone withdrawal. These results should be weighed before spironolactone withdrawal was attempted.

Circulating PGLYRP1 Levels as a Potential Biomarker for Coronary Artery Disease and Heart Failure.

ABSTRACT: Coronary artery disease (CAD) and associated comorbidities such as heart failure (HF) remain the leading cause of morbidity and mortality worldwide attributed to, at least partially, the lack of biomarkers for efficient disease diagnosis. Here, we evaluated the diagnostic potential of serum peptidoglycan recognition protein 1 (PGLYRP1), an important component of the innate immunity and inflammation system, for both CAD and HF. A machine-learning method (random forest) was used to evaluate the clinical utility of circulating PGLYRP1 for diagnosis of CAD and HF in a total of 370 individuals. Causal links of chronic serum PGLYRP1 elevation to both diseases were further explored in ApoE-/- mice. The serum levels of PGLYRP1 were significantly higher in individuals with either chronic CAD or acute coronary syndrome than those in those without coronary artery stenosis (the control group) and even more pronounced in CAD individuals with concomitant HF. Our random forest classifier revealed that this protein performed better than other recommended clinical indicators in distinguishing the CAD from the control individuals. In addition, this protein associates more with the biomarkers of HF including left ventricular ejection fraction than inflammation. Notably, our mice experiment indicated that long-term treatment with recombinant PGLYRP1 could significantly impair the cardiovascular system as reflected from both increased atherogenic lesions and reduced fractional shortening of the left ventricle. Our findings, therefore, supported the circulating levels of PGLYRP1 as a valuable biomarker for both CAD and HF.

Cyclin-Dependent Kinase Inhibitor 2b Controls Fibrosis and Functional Changes in Ischemia-Induced Heart Failure via the BMI1-p15-Rb Signalling Pathway.

BACKGROUND: Cardiac fibrosis is an important cause of heart failure (HF) after myocardial infarction (MI). Cyclin-dependent kinase inhibitor 2b (CDKN2b) regulates the cell cycle by encoding the p15 protein and participates in the development of various tumours. However, the role of CDKN2b/p15 in cardiac fibrosis and HF after MI remains unclear. METHODS: Lentivirus was used to induce the silence and overexpression of CDKN2b. Cardiac function was detected with the use of echocardiography. Immunohistochemistry, immunofluorescence, Western blotting, Cell Counting Kit 8, and wound healing assay were used to illustrate the potential mechanism associated with CDKN2b. RESULTS: The p15 protein expression was significantly down-regulated in both human and mouse failing hearts. Cardiac down-regulation of CDKN2b promoted myocardial fibrosis and worsened cardiac function in MI mice, while systemic CDKN2b silencing induced diastolic dysfunction in vivo. In addition, cardiac overexpression of CDKN2b ameliorated cardiac fibrosis and improved cardiac function in MI mice. Mechanistically, silencing CDKN2b gene enhanced the phosphorylation of retinoblastoma (Rb) protein and reinforced the migration and proliferation capabilities of cardiac fibroblasts. B Lymphoma Mo-MLV insertion region 1 homolog (BMI1) was up-regulated in failing heart and inversely regulated the expression of CDKN2b/p15 and the phosphorylation of Rb protein. The BMI1-p15-Rb signalling pathway is a potential mechanism of ischemia-induced cardiac fibrosis and HF. CONCLUSIONS: Cardiac fibrosis and heart function could be worsened by the down-regulation and relieved by the up-regulation of CDKN2b/p15 in ischemia-induced HF via regulating the proliferation and migration capabilities of cardiac fibroblasts. These effects could be partially explained by the regulation of the BMI1-p15-Rb signalling pathway.

Depletion of ß3-adrenergic receptor induces left ventricular diastolic dysfunction via potential regulation of energy metabolism and cardiac contraction.

Left ventricular diastolic dysfunction (LVDD) is a central perturbation in heart failure with preserved ejection fraction, and there are currently no effective remedies to improve LVDD in clinical practice. The ß3-adrenergic receptor (ADRB3) was reported to play protective effects on inhibiting myocardial fibrosis in response to hemodynamic stress. However, the effects of ADRB3 on LVDD and its underlying mechanisms are still undefined. In the current study, the role of ADRB3 in LVDD was identified in ADRB3-knockout mice. Echocardiography parameters showed that depletion of ADRB3 had little effect on cardiac systolic function but obviously led to cardiac diastolic dysfunction in vivo. Proteomics (including the global proteome, phosphorylated and acetylated proteome) and bioinformatics analysis (including GO analysis, KEGG pathway analysis, GO-Tree network, Pathway-Act network, and protein-protein interaction network) were performed on cardiac specimens of ADRB3-KO mice and wild-type mice. The results showed that the cardiac energy metabolism (especially the citrate cycle), actin cytoskeleton organization, and cardiac muscle contraction (related to mitogen-activated protein kinase, toll-like receptor, and ErbB signalling pathway) were potential core mechanisms underlying ADRB3-KO-induced LVDD. In addition, the protein-protein interaction network indicated that the core proteins associated with ADRB3-KO-induced LVDD were FGG, ALDH1A1, FGA, APOC3, SLC4A1, SERPINF2, HP, CTNNB1, and TKT. In conclusion, the absence of ADRB3 leads to LVDD, which is potentially associated with the regulation of cardiac energy metabolism, actin cytoskeleton organization, and cardiac muscle contraction.

MicroRNA-19b-1 reverses ischaemia-induced heart failure by inhibiting cardiomyocyte apoptosis and targeting Bcl2 l11/BIM.

Ischaemia induces cardiac apoptosis and leads to a loss of cardiac function and heart failure after myocardial infarction. MicroRNA-19b-1 (miR-19b-1), a key member of the miR-17/92 cluster, plays crucial roles in inhibiting apoptosis. However, the role of miR-19b-1 in ischaemia-induced heart failure remains unknown. In this study, ischaemia resulted in cardiac apoptosis and the suppression of miR-19b-1 expression, whereas miR-19b-1 overexpression inhibited ischaemia-induced cardiac apoptosis in vivo and in vitro. Moreover, miR-19b-1 not only attenuated the infarct size but also ameliorated heart failure after myocardial infarction, including the changes in the left ventricular ejection fraction and volume load. Mechanically, miR-19-1 targeted and downregulated the mRNA and protein expression of Bcl2l11/BIM, a pro-apoptotic gene of the Bcl-2 family. Together, these results revealed an essential role of miR-19b-1 in ischaemia-induced heart failure.

Decreased circulating catestatin levels are associated with coronary artery disease: The emerging anti-inflammatory role.

BACKGROUND AND AIMS: The neuropeptide catestatin (CST) is an endogenous nicotinic cholinergic antagonist that acts as pleiotropic cardiac protective hormone. This study investigated the association between CST and coronary artery disease (CAD) and the underlying mechanisms. METHODS AND RESULTS: The serum concentration of CST among 224 CAD patients and 204 healthy controls was compared, and its association with atherosclerosis severity in 921 CAD patients was further analyzed. Compared to healthy subjects, serum CST concentration was lower in patients with CAD [1.14 (1.05-1.24) ng/mL vs. 2.15 (1.92-2.39) ng/mL, p < 0.001] and was inversely correlated with disease severity (r = -0.208, p < 0.001). In cultured endothelial cells, CST suppressed TNF-α-elicited expression of inflammatory cytokines and adhesion molecules by activating angiotensin-converting enzyme-2 (ACE2). Administration of CST reduced leukocyte-endothelium interactions in vitro and in vivo, and attenuated the development of atherosclerotic in ApoE-/- mice fed a high-fat diet. These protective effects by CST were blocked by an ACE2 inhibitor. CONCLUSIONS: Serum CST concentration is lower in CAD patients and is inversely associated with the severity of atherosclerosis. CST acts as a novel anti-atherogenic peptide that inhibits inflammatory response and EC-leukocyte interactions via an ACE2-dependent mechanism.

Mediating Effect of Diabetes Mellitus on the Association Between Chromosome 9p21.3 Locus and Myocardial Infarction Risk: A Case-Control Study in Shanghai, China.

Background: Previous genome-wide association studies revealed that the chromosome 9p21.3 locus is associated with an increased risk of myocardial infarction (MI) and diabetes mellitus (DM). However, it is unclear whether the 9p21.3-MI association is direct or mediated by pathways related to DM. Study Design: We applied mediation analysis to examine the potential mediating effect of DM on the association between the 9p21.3 genetic risk score (GRS; ranged from 0 to 8) and MI in a case-control study of 865 MI patients and 927 controls without coronary artery disease (CAD). The GRS combining 4 lead 9p21.3 single nucleotide polymorphisms (rs1333040, rs4987574, rs2383207, and rs1333049) was constructed. Results: Each 1 unit increase in weighted 9p21.3 GRS was associated with a 9% increased DM risk (95% confidence interval (CI) 1.00, 1.19) in the control group and a 14% increased MI risk (95% CI 1.09, 1.20). Mediation analyses yielded a direct-effect odds ratio (OR) of 1.06 (95% CI 1.04, 1.08) and an indirect-effect OR of 1.00 (95% CI 0.99, 1.01) for weighted GRS. DM mediated 4.40% (95% CI 3.42, 6.52) of the total association between the weighted GRS and MI risk. Individuals with the highest quartile of 9p21.3 GRS and DM had a 6-fold higher MI risk than those with the lowest quartile of 9p21.3 GRS and non-DM (OR 6.03, 95% CI 3.48, 10.5). Conclusion: DM is a weak mediator that explains a small fraction of the 9p21. 3-MI association in Chinese adults. Nevertheless, there is a strong synergistic effect between DM and the 9p21.3 GRS on MI risk.

Conditional Inference Tree for Multiple Gene-Environment Interactions on Myocardial Infarction.

BACKGROUND AND AIMS: Identifying gene-environment interaction in the context of multiple environmental factors has been a challenging task. We aimed to use conditional inference tree (CTREE) to strata myocardial infarction (MI) risk synthesizing information from both genetic and environmental factors. METHODS: We conducted a case-control study including 1440 Chinese men (730 MI patients and 710 controls). We first calculated a weighted genetic risk score (GRS) by combining 25 single nucleotide polymorphisms (SNPs) that had been identified to be associated with coronary artery diseases in previous genome wide association studies. We then developed a CTREE model to interpret the gene-environment interaction network in predicting MI. RESULTS: We detected high-order interactions between dyslipidemia, GRS, smoking status, age and diabetes. Of all the variables examined, high density lipoprotein cholesterol (HDL-C) of 1.25 mmlo/L was identified as the key discriminator. The subsequent splits of MI were low density lipoprotein cholesterol (LDL-C) of 4.01 mmol/L and GRS of 20.9. We found that individuals with HDL-C ≤1.25 mmol/L, GRS >20.9 and lipoprotein (a) > 0.09 g/L had a higher risk of MI than those who at the lowest risk group (OR: 5.89, 95% CI: 3.99-8.69). This magnitude of MI risk was similar to the combination of HDL-C ≤1.25 mmol/L, GRS ≤20.9, smoking and lipoprotein (a) > 0.15 g/L (OR: 5.49, 95% CI: 3.51-8.58). CONCLUSIONS: The multiple interactions between genetic and environmental factors can be visually present via the CTREE approach. The tree diagram also simplifies the decision making procedure by answering a sequence of questions along the branches.

p-Cresyl sulfate promotes the formation of atherosclerotic lesions and induces plaque instability by targeting vascular smooth muscle cells.

Coronary atherosclerosis is a major complication of chronic kidney disease. This condition contributes to the increased mortality in dialysis patients. p-Cresyl sulfate (PCS) is a prototype of protein-bound uremic toxins that cannot be efficiently removed through routine dialysis procedures. In the present study, ApoE(-/-) mice that underwent 5/6 nephrectomy were randomly divided into two groups, namely, vehicle-treated group (n = 20) and PCS-treated group (n = 20). Mice were sacrificed for en face and immunohistological analyses after 8 or 24 weeks of high-fat diet. Rat aortic vascular smooth muscle cells (VSMCs) were treated with phosphate buffer solution or 500 µmol/L PCS for in vitro evaluation. PCS-treated mice were observed to suffer increased atherosclerotic lesions after eight weeks of PCS administration. Moreover, 24 weeks of PCS administration also markedly increased the vulnerability index of aortic plaques. PCS was also observed to facilitate the migration and proliferation of VSMCs during the progression of the disease. Moreover, PCS disturbed the balance between matrix metalloproteinases and tissue inhibitor of metalloproteinases within the plaques. Thus, PCS played a vital role in promoting atherogenesis and disturbing the stability of formed plaques probably by targeting VSMCs.

Tetranectin as a Potential Biomarker for Stable Coronary Artery Disease.

This cross-sectional study tested the hypothesis that decreased serum levels of tetranectin (TN), a regulator of the fibrinolysis and proteolytic system, is associated with the presence and severity of CAD. We conducted a systematic serological and immunohistochemical (IHC) analysis to respectively compare the TN levels in serum and artery samples in CAD patients and healthy controls. Our results showed that serum levels of TN were significantly lower in patients with CAD than in healthy controls. Further analysis via trend tests revealed that serum TN levels correlated with the number of diseased arteries. Besides, the multivariate logistic regression model revealed TN as an independent factor associated with the presence of CAD. Additionally, IHC analysis showed that TN expression was significantly higher in atherosclerotic arteries as compared to healthy control tissues. In conclusion, our study suggests that increased serum TN level is associated with the presence and severity of diseased coronary arteries in patients with stable CAD.

Association of natriuretic peptide polymorphisms with left ventricular dysfunction in southern Han Chinese coronary artery disease patients.

BACKGROUND: Left ventricular dysfunction (LVD) occurs with myocardial ischemia and coronary artery disease (CAD). The natriuretic peptide system has compensatory vasodilatory, natriuretic and paracrine effects on LVD and subsequent heart failure. The aim of this study was to investigate the relationship between natriuretic peptide polymorphisms and risk of LVD in CAD patients. METHODS: We recruited 747 consecutive Southern Han Chinese patients with angiographically confirmed CAD, 201 had a reduced left ventricle ejection fraction (LVEF ≤45%, LVD group) and 546 had a preserved left ventricle ejection fraction (LVEF >45%). The reduced and preserved LVEF groups were matched by gender and age. Taqman assays were performed to identify five polymorphisms in the NPPA-NPPB locus (rs5065, rs5063, rs632793, rs198388 and rs198389). RESULTS: Single-locus analyses found no significant difference in the allele and genotype frequencies of the reduced and preserved LVEF group, even after adjusting for confounding factors. Subgroup analyses performed by hyperlipidemia (HLP) demonstrated 3 polymorphisms, rs632793 (OR = 0.31, 95% CI 0.1-0.93, P = 0.04), rs198388 (OR = 0.26, 95% CI 0.09-0.79, P = 0.02) and rs198389 (OR = 0.26, 95% CI 0.09-0.80, P = 0.02) were associated with the reduced risk of LVD. No CAD-susceptible haplotypes were identified. Multifactor dimensionality reduction analysis did not detect any gene-to-gene interactions among the five loci. Three loci (rs5063, rs632793 and rs198388) formed the best model with the maximum testing accuracy (39.89%) and cross-validation consistency (10/10). CONCLUSION: Three NPPA-NPPB polymorphisms (rs632793, rs198388 and rs198389) were associated with reduced risk of LVD in CAD patients with HLP.

Interactive association of five candidate polymorphisms in Apelin/APJ pathway with coronary artery disease among Chinese hypertensive patients.

BACKGROUND: Via sequencing the genes of apelin/angiotensin receptor-like 1 (apelin/APJ) pathway, we have recently identified and validated four common polymorphisms (rs3761581, rs56204867, rs7119375, and rs10501367) implicated in the development of hypertension. Extending these findings, we, in Chinese hypertensive patients, sought to investigate the association of these four polymorphisms and one additional promising candidate (rs9943582) from this pathway with the risk of developing coronary artery disease (CAD). METHODOLOGY/PRINCIPAL FINDINGS: Genotypes were obtained from 994 sporadic CAD patients and 708 age- and sex-matched controls. All participants were hypertensives and angiographically-confirmed. Data were analyzed by Haplo.Stats and multifactor dimensionality reduction (MDR) softwares. Genotype distributions of five examined polymorphisms satisfied Hardy-Weinberg equilibrium in controls of both genders. Single-locus analyses exhibited no significant differences in the genotype/allele frequencies of examined polymorphisms between CAD patients and controls (P>0.05), even after controlling traditional cardiovascular confounders. In haplotype analyses, low-penetrance haplotype G-A (in order of rs56204867 and rs3761581 from apelin gene) was significantly overrepresented in controls (1.73%) relative to in CAD patients (0.4%) in males (P = 0.047). Further interaction analyses suggested an overall best MDR model including rs3761581 in males (P = 0.0408) and including rs7119375 and rs9943582 in females (P<0.0001), which were further substantiated in the classical logistical regression model. CONCLUSIONS: Our findings demonstrated a contributive role of low-penetrance haplotype in apelin gene on CAD in males, and more importantly, interactive effects of genetic defects in apelin/APJ pathway might confer a potential risk in Chinese hypertensive patients.

Variants in exon 11 of MEF2A gene and coronary artery disease: evidence from a case-control study, systematic review, and meta-analysis.

BACKGROUND: Coronary artery disease (CAD) is the most common heart disease worldwide. Association of CAD with variants in the myocyte enhancer factor 2A (MEF2A) gene, the first identified CAD-causing gene, has attracted special attention but the results are controversial. We aimed to evaluate this genetic association via a case-control study and meta-analysis. METHODOLOGY/PRINCIPAL FINDINGS: We performed a case-control association study to investigate the relationship between variations in exon 11 of MEF2A gene and CAD in 1045 sporadic patients and 1008 controls enrolled angiographically among southern Chinese population, and then the data from this study were compared and discussed in a systematic review and meta-analysis with all available published studies on MEF2A gene and CAD. In total, eight variants were identified (21-bp deletion, CAG repeats, CCG repeats, a CCA deletion and four SNPs). No significant link was observed between the common (CAG)(n) polymorphism and CAD, whereas the rare 21-bp deletion was detected only in five affected individuals. The meta-analysis of (CAG)(n) polymorphism and CAD risk, including nine studies with 3801 CAD patients and 4020 controls, also provided no convincing evidence for the genetic association, even upon stratification by race (mainly Whites and Chinese). However, the 21-bp deletion was regarded as a potentially logical, albeit undetermined, candidate for CAD in the following systematic review. CONCLUSIONS/SIGNIFICANCE: Our findings failed to demonstrate a correlation between (CAG)(n) polymorphism with CAD, however, we concluded that the rare 21-bp deletion might have a more compelling effect on CAD than the common (CAG)(n) polymorphism, and MEF2A genetic variant might be a rare but specific cause of CAD/MI.