Division of Cardiology, Policlinico Casilino, ASL Rome B, Rome, Italy.
Division of Cardiology, University of Torino, Department of Medical Sciences, Città della Salute e della Scienza Hospital, Torino, Italy.
J Am Coll Cardiol. 2016 Mar 29;67(12):1427-1440. doi: 10.1016/j.jacc.2016.01.024.
Risk stratification in asymptomatic patients remains by far the most important yet unresolved clinical problem in the Brugada syndrome (BrS).
This study sought to analyze the usefulness of electrocardiographic parameters as markers of sudden cardiac death (SCD) in BrS.
This study analyzed data from 347 consecutive patients (78.4% male; mean age 45 ± 13.1 years) with spontaneous type 1 BrS by ECG parameters but with no history of cardiac arrest (including 91.1% asymptomatic at presentation, 5.2% with a history of atrial fibrillation [AF], and 4% with a history of arrhythmic syncope). Electrocardiographic characteristics at the first clinic visit were analyzed to predict ventricular fibrillation (VF)/SCD during follow-up.
During the follow-up (48 ± 38 months), 276 (79.5%) patients remained asymptomatic, 39 (11.2%) developed syncope, and 32 (9.2%) developed VF/SCD. Patients who developed VF/SCD had a lower prevalence of SCN5A gene mutations (p = 0.009) and a higher prevalence of positive electrophysiological study results (p < 0.0001), a family history of SCD (p = 0.03), and AF (p < 0.0001). The most powerful marker for VF/SCD was a significant S-wave (≥0.1 mV and/or ≥40 ms) in lead I. In the multivariate analysis, the duration of S-wave in lead I ≥40 ms (hazard ratio: 39.1) and AF (hazard ratio: 3.7) were independent predictors of VF/SCD during follow-up. Electroanatomic mapping in 12 patients showed an endocardial activation time significantly longer in patients with an S-wave in lead I, mostly because of a significant delay in the anterolateral right ventricular outflow tract.
The presence of a wide and/or large S-wave in lead I was a powerful predictor of life-threatening ventricular arrhythmias in patients with BrS and no history of cardiac arrest at presentation. However, the prognostic value of a significant S-wave in lead I should be confirmed by larger studies and by an independent confirmation cohort of healthy subjects.
在无症状患者中进行风险分层仍然是 Brugada 综合征（BrS）中最重要但尚未解决的临床问题。
本研究旨在分析心电图参数作为 BrS 患者心源性猝死（SCD）标志物的有用性。
本研究分析了 347 例连续自发性 1 型 BrS 患者（78.4%为男性；平均年龄 45±13.1 岁）的心电图参数数据，但无心脏骤停史（包括 91.1%首发时无症状，5.2%有房颤[AF]史，4%有心律失常性晕厥史）。分析首次就诊时的心电图特征，以预测随访期间室颤（VF）/SCD 的发生。
在随访期间（48±38 个月），276 例（79.5%）患者无症状，39 例（11.2%）发生晕厥，32 例（9.2%）发生 VF/SCD。发生 VF/SCD 的患者 SCN5A 基因突变的发生率较低（p=0.009），电生理检查结果阳性的发生率较高（p<0.0001），家族性 SCD 史（p=0.03）和 AF（p<0.0001）。预测 VF/SCD 的最有力标志物是 I 导联 S 波明显（≥0.1 mV 和/或≥40 ms）。多变量分析显示，I 导联 S 波持续时间≥40 ms（危险比：39.1）和 AF（危险比：3.7）是随访期间 VF/SCD 的独立预测因子。对 12 例患者进行心内电描记图显示，I 导联 S 波存在时，心内膜激活时间明显延长，主要是因为前外侧右心室流出道明显延迟。
在无心脏骤停史的 BrS 患者中，I 导联出现宽而/或大 S 波是发生危及生命的室性心律失常的有力预测因子。然而，I 导联出现明显 S 波的预后价值需要更大规模的研究和健康受试者的独立确认队列来证实。
