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Abstract：
Brugada syndrome is characterized by pronounced J-ST segment elevation in the right precordial leads on surface electrocardiograms. The etiological underpinnings of these distinctive features have been the subject of extensive debate, encompassing various theories related to repolarization anomalies and conduction irregularities. Genetic investigations have unveiled SCN5A, the gene encoding NaV1.5, a critical sodium channel, as the most frequently implicated causative gene, with mutations typically manifesting as loss of function. Nonetheless, the detection rate of SCN5A mutations remains below 20%, underscoring the intricate genetic landscape of the syndrome. Histological analyses have divulged localized structural irregularities, primarily marked by fibrotic alterations, within the right ventricular outflow tract. Electrophysiological inquiries employing direct epicardial mapping techniques have uncovered localized conduction impediments concomitant with modifications in unipolar morphologies within the J-ST segment. Thus, the theory positing conduction abnormalities emerges as a compelling mechanism accounting for J-ST segment elevation. However, the precise mechanisms governing the onset of life-threatening tachyarrhythmias remain shrouded in uncertainty. Recent clinical case reports have proffered evidence supporting the notion that phase 2 reentry, arising from the marked heterogeneity in action potentials within the epicardial domain, may serve as the instigator of premature ventricular contractions, ultimately culminating in ventricular fibrillation. In light of these developments, it becomes increasingly evident that comprehending the mechanisms underlying the electrocardiographic manifestations and lethal arrhythmias in Brugada syndrome necessitates the consideration of a multifaceted perspective, transcending the binary discourse of repolarization versus depolarization anomalies.
摘要：
Brugada综合征的特征是体表心电图右心前导联J-ST段抬高。这些独特特征的病因学基础一直是广泛辩论的主题，涵盖与复极化异常和传导不规则相关的各种理论。基因调查公布了SCN5A，编码NaV1.5的基因，一种关键的钠通道，作为最常见的致病基因，突变通常表现为功能丧失。尽管如此，SCN5A基因突变检出率保持在20%以下,强调了该综合征复杂的遗传景观。组织学分析揭示了局部结构不规则，主要以纤维化改变为标志，在右心室流出道内。采用直接心外膜标测技术的电生理查询已发现了伴随J-ST段内单极形态改变的局部传导障碍。因此，假定传导异常的理论是一种令人信服的机制，可解释J-ST段抬高。然而,控制危及生命的快速性心律失常发作的确切机制仍然笼罩在不确定性之中.最近的临床病例报告提供了支持第二阶段折返的观点的证据，由于心外膜区域动作电位的显著异质性，可以作为室性早搏的煽动者，最终导致心室纤颤.鉴于这些发展，越来越明显的是，理解Brugada综合征的心电图表现和致死性心律失常的潜在机制需要考虑多方面的观点，超越复极化与去极化异常的二元论述。
