Gene Polymorphism and Recurrent Atrial Fibrillation after Catheter Ablation: A Comprehensive Review.

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, but its pathogenesis is still poorly understood. Catheter ablation is one of the most effective treatments for AF, but recurrence after ablation remains a challenge. There has been much research into the association of AF recurrence with several factors, including genetics. Over the past decade or so, significant advances have been made in the genetic architecture of atrial fibrillation. Genome-wide association studies (GWAS) have identified over 100 loci for genetic variants associated with atrial fibrillation. However, there is relatively little information on the systematic assessment of the genes related to AF recurrence after ablation. In this review article, we highlight the value of genetic polymorphisms in atrial fibrillation recurrence after catheter ablation and their potential mechanisms in the recurrence process to enhance our understanding of atrial fibrillation recurrence and contribute to individualized treatment strategies for patients with AF.

Genetically Elevated Serum Uric Acid and Renal Function in an Apparently Healthy Population.

BACKGROUND: The association between uric acid and kidney disease has been extensively investigated. Numerous studies have reported the association between circulating levels of uric acid and renal function. OBJECTIVES: To test, by the Mendelian randomization method, whether there is a causal association between circulating levels of uric acid and renal function. METHODS: In 989 participants, estimated glomerular filtration rate (eGFR) was calculated, the circulating level of uric acid was tested, and the uric acid polymorphism (rs11722228) was genotyped. RESULTS: After adjusting for age, gender, smoking history, alcohol intake, antihypertensive medication, body mass index, waist-to-hip ratio, and levels of urea nitrogen and creatinine, a significant allelic difference was found in uric acid levels for each genotype (p < 0.0001). Furthermore, the circulating levels of uric acid were negatively associated with eGFR after adjusting for cardiovascular risk factors and other potential confounders (p < 0.0001). Meanwhile, eGFR was significantly associated with the genotypes of rs11722228 (ß = -0.07; p = 0.02). CONCLUSIONS: Evidence from the Mendelian randomization approach implied a causal relationship between uric acid and renal function in an apparently healthy population.

Association of CYBA rs7195830 polymorphism with estimated glomerular filtration rate in an adult Han sample from Jiangsu province, China.

BACKGROUND: Reactive oxygen species are thought to contribute to the development of renal damage. The P22phox subunit of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase, encoded by the cytochrome b245a polypeptide gene, CYBA, plays a key role in superoxide anion production. We investigated the association of CYBA rs7195830 polymorphism with estimated glomerular filtration rate (eGFR) and the role it plays in the pathogenesis of chronic kidney disease (CKD) in a Han Chinese sample. METHODS: The Gaoyou study enrolled 4473 participants. Serum levels of creatinine were measured and eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equations. The CYBA polymorphisms were genotyped. Then we investigated the association between eGFR and the rs7195830 polymorphism in the recessive model. RESULTS: The AA genotype of rs7195830 was associated with significantly lower values of eGFR compared with the GG and AG genotypes ((102.76 ± 17.07) ml×min(-1)×1.73 m(-2) vs. (105.08 ± 16.30) ml×min(-1)± 1.73 m(-2)). The association remained significant in the recessive model after adjusting for age, gender, body mass index, smoking, hypertension, diabetes mellitus, uric acid, triglyceride, low density lipoprotein cholesterol and high density lipoprotein cholesterol (ß=1.666, P=0.031). The rs7195832 AA genotype was an independent risk factor for CKD: eGFR <60 ml×min(-1)×1.73 m(-2) (odds ratio=3.32; 95% CI=1.21-9.13). CONCLUSION: The AA genotype of rs7195830 is independently associated with lower estimated glomerular filtration rate and is significantly associated with CKD.

[Relationship between high-sensitive c-reactive and blood pressure].

OBJECTIVE: To investigate the relationship between c-reactive protein (CRP) and blood pressure in a general population. METHODS: We randomly selected 3889 subjects aged 18 - 74 years stratified by gender and age in Baqiao, a rural area of Jiangsu Province. A standardized questionnaire was used to collect information on medical history, smoking, alcohol intake and use of medications. Blood pressure was measured by mercury sphygmomanometer. Serum CRP (hCRP) concentration was measured using a high sensitivity BNprosec immunonephelometric assay. Subjects were divided into 4 groups according to their interquartile range of CRP levers: group Q1 (men hCRP < 2.04 mg/L; women hCRP < 1.80 mg/L); group Q2 (men 2.04 mg/L ≤ hCRP < 3.01 mg/L; women 1.80 mg/L ≤ hCRP < 2.76 mg/L); group Q3 (men 3.01 mg/L ≤ hCRP < 4.14 mg/L; women 2.76 mg/L ≤ hCRP < 3.84 mg/L); and group Q4 (men 4.14 mg/L ≤ hCRP; women 3.84 mg/L ≤ hCRP). RESULTS: Systolic blood pressure (SBP, adjusted P = 0.016) and pulse pressure (PP, adjusted P = 0.003) of men and PP (adjusted P = 0.002) of women were increased in proportion to increased CRP levels. Diastolic blood pressure was not associated with CRP levels. Multiple stepwise regression analysis showed that logCRP was independently associated with SBP and PP in men and PP in women. hCRP was independently associated with hypertension in men. Compared with group Q1, male people in group Q4 faced a 40.4% (95% confidence interval: 4.9% - 87.9%) higher risk of hypertension. CONCLUSIONS: hCRP was independently associated with PP in men and women, and SBP in men. hCRP was independently associated with hypertension in men but not in women in this study population.