AUTHOR=Yang Yihan , Hu Dan , Sacher Frederic , Kusano Kengo F. , Li Xinye , Barajas-Martinez Hector , Hocini Mélèze , Li Yanda , Gao Yonghong , Shang Hongcai , Xing Yanwei 

TITLE=Meta-Analysis of Risk Stratification of SCN5A With Brugada Syndrome: Is SCN5A Always a Marker of Low Risk?

JOURNAL=Frontiers in Physiology

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2019.00103

DOI=10.3389/fphys.2019.00103

ISSN=1664-042X

ABSTRACT=<p><bold>Background:</bold><italic>SCN5A</italic> with Brugada syndrome (BrS) is not commonly considered as an independent risk marker for subsequent cardiac events. However, the risk of <italic>SCN5A</italic> combined with other clinical characteristics has not been fully investigated.</p><p><bold>Objectives:</bold> The aim of this study is to investigate and evaluate risk stratification and related risk factors of <italic>SCN5A</italic> in BrS.</p><p><bold>Methods:</bold> The databases of PubMed, EMBASE, Cochrane Library, MEDLINE, Chinese National Knowledge Infrastructure (CNKI) and Wanfang Data were searched for related studies published from January 2002 to May 2018 followed by meta-analysis. The BrS patients who underwent <italic>SCN5A</italic> gene tests were included. The prognosis and risk stratification of <italic>SCN5A</italic> combined with symptoms and asymptoms diagnosis in BrS, electrophysiology study (EPS) were then investigated and evaluated. Outcomes were defined as ventricular tachycardia/fibrillation (VT/VF), sudden cardiac death (SCD).</p><p><bold>Results:</bold> Eleven suitable studies involving 1892 BrS patients who underwent <italic>SCN5A</italic> gene tests were identified. <italic>SCN5A</italic> (+) was not considered to be a significant predictor of future cardiac events (95% CI: 0.89–2.11; <italic>P</italic> = 0.15; <italic>I</italic><sup>2</sup> = 0%). However, <italic>SCN5A</italic> (+) patients with symptoms at diagnosis revealed a higher prevalence of future VT/VF, SCD compared to <italic>SCN5A</italic> (–) patients with symptoms at diagnosis. (95% CI: 1.06–3.70; <italic>P</italic> = 0.03 <italic>I</italic><sup>2</sup> = 0%) Among asymptomatic patients, the risk did not significantly differ between <italic>SCN5A</italic> (+) patients and <italic>SCN5A</italic> (–) patients. (95% CI: 0.51–4.72; <italic>P</italic> = 0.45 <italic>I</italic><sup>2</sup> = 0 %). In an investigation involving patients in EPS (–) BrS electrocardiogram (ECG), the risk of <italic>SCN5A</italic> (+) is higher than that of <italic>SCN5A</italic> (–) (<italic>P</italic> &lt; 0.001).</p><p><bold>Conclusions:</bold> In BrS patients with symptoms at diagnosis or EPS (–), the meta-analysis suggests that <italic>SCN5A</italic> (+) are at a higher risk of arrhythmic events than <italic>SCN5A</italic> (–).</p>