Ablatogenomics: can genotype guide catheter ablation for cardiac arrhythmias?

Atrial fibrillation and autonomic nervous system: A translational approach to guide therapeutic goals

The autonomic nervous system (ANS) is known to play an important role in the genesis and maintenance of atrial fibrillation (AF). Biomolecular and genetic mechanisms, anatomical knowledges with recent diagnostic techniques acquisitions, both invasive and non-invasive, have enabled greater therapeutic goals in patients affected by AF related to ANS imbalance. Catheter ablation of ganglionated plexi (GP) in the left and right atrium has been proposed in varied clinical conditions. Moreover interesting results arise from renal sympathetic denervation and vagal nerve stimulation. Despite all this, in the scenario of ANS modulation translational strategies we necessary must consider the treatment or correction of dynamic factors such as obesity, obstructive sleep apnea, lifestyle, food, and stress. Finally, new antiarrhythmic drugs, gene therapy and "ablatogenomic" could be represent exciting future therapeutic perspectives.

Role of Endothelial Nitric Oxide Synthase Polymorphisms in Atrial Fibrillation: A PRISMA-Compliant Meta-Analysis

BACKGROUND Research interest in endothelial nitric oxide synthase(eNOS) polymorphisms and atrial fibrillation (AF) has grown in last recent years, but the results of individual studies are inconsistent due to their small sample sizes. MATERIAL AND METHODS We searched databases for eligible studies on eNOS and AF, extracted the relevant data, and rigorously screened them according to inclusion and exclusion criteria. Then, we evaluated the study quality according to the Newcastle-Ottawa scale score, and we pooled the odds ratios (ORs) and 95% confidence intervals (CIs) by using a random-effects model or fixed-effects model based on inter-study heterogeneity. In addition, we performed subgroup analysis and sensitivity analysis and assessed publication bias. RESULTS According to the inclusion and exclusion criteria, we finally found 8 studies in this search. The recessive (OR=0.81; 95% CI=0.67 to 0.97; p=0.988; I²=0.0%) model showed that the eNOS 786T/C polymorphism was relevant to AF. We also found that the eNOS 786T/C polymorphism decreases the risk of AF, especially in white people (OR=0.81; 95% CI=0.67 to 0.97; P=0.023 for recessive model) and in the control population (OR=0.79; 95% CI=0.65 to 0.97; P=0.022 for recessive model). We found no obvious publication bias. CONCLUSIONS The eNOS gene loci 786T/C polymorphism is relevant to the risk of AF. Our results suggest that the 786T/C polymorphism significantly decreases AF risks in white people and control populations. Larger studies are required for further evaluation.

Association between KCNE1 G38S gene polymorphism and risk of atrial fibrillation: A PRISMA-compliant meta-analysis

BACKGROUND

Previous case-control studies on association between KCNE1 G38S polymorphism and risk of atrial fibrillation (AF) have been published but because of the conflicting results and small sample size of individual studies, the consolidated result is still controversial.

OBJECTIVES

The aim of this study was to explore the relationship between KCNE1 G38S polymorphism and risk of AF.

METHODS

We performed a comprehensive literature search on PubMed, Embase, OVID, Web of Science, Wan Fang, and CNKI databases up to March 10, 2017 in English and Chinese languages. Two of the authors individually extracted study data and assessed the study quality using Newcastle-Ottawa scale. Odds ratios (ORs) and 95% confidence intervals (CIs) were combined in different genetic models for evaluation using a random-effect model or fixed-effect model according to interstudy heterogeneity.

RESULTS

There were totally 14 independent case-control studies of 2810 patients and 3080 healthy controls included. Significant associations were found between KCNE1 G38S polymorphism and AF in overall population under all genetic models: allelic (OR: 1.34, 95% CI: 1.24-1.45, P < .001), homozygous (OR: 1.90, 95% CI: 1.61-2.24, P < .001), heterozygous (OR: 1.43, 95% CI: 1.21-1.68, P < .001), recessive (OR: 1.42, 95% CI: 1.20-1.69, P < .001), dominant genetic model (OR: 1.62, 95% CI: 1.39-1.89, P < .001). Subgroup analyses indicated similar association in Chinese and white.

CONCLUSIONS

The G38S polymorphism in the KCNE1 gene can significantly increase the risk of AF in both Chinese and white.