Univ Rennes, CHU Rennes, Inserm, LTSI - UMR 1099, Rennes, France.
ESAII Department, EUETIB, CREB, Universitat Politècnica de Catalunya, Barcelona, Spain.
Adv Exp Med Biol. 2018;1065:181-190. doi: 10.1007/978-3-319-77932-4_12.
Cardiac events in patients with Brugada syndrome (BS) typically occur at rest and mainly during sleep, suggesting that changes in autonomic modulation play an important role in the arrhythmogenesis of the disease. Moreover, sex differences in clinical manifestations of BS have been reported, identifying male patients with worse prognosis. The aim of our work was to assess and compare, according to sex, autonomic response to exercise in a clinical series including 105 BS patients.
Standard 12-lead electrocardiogram recordings were collected during a physical stress test divided into four phases: warm-up, incremental exercise, active recovery, and passive recovery. Spectral non-stationary heart rate variability indicators were extracted by means of a smoothed pseudo Wigner-Ville distribution approach that adapts frequency bands to respiratory information. These indicators were then averaged in non-overlapped windows of 1 min for each patient to compare groups at each minute of the physical stress test.
From the last minute of warm-up and until the third minute of incremental exercise, asymptomatic male patients presented significantly greater low-frequency (LF) values ([Formula: see text]: p = 0.015;[Formula: see text]: p = 0.024; [Formula: see text]: p = 0.011; [Formula: see text]: p = 0.002) than asymptomatic females. Conversely, asymptomatic women showed increased vagal modulation during the first minutes of incremental exercise ([Formula: see text]: p = 0.031; [Formula: see text]: p = 0.001). However, no significant differences were observed between symptomatic male and female patients.
As previously reported in healthy subjects, enhanced parasympathetic and decreased sympathetic tones appear to be not only greater in women but also defensive during cardiac stress. Based on the results, asymptomatic patients presented same-sex tendencies. However, we observed that symptomatic males developed a more female-like autonomic modulation, probably related to a more protective autonomic response to exercise. These results could be a step forward toward the understanding of the autonomic function in BS along with a potential impact on risk stratification.
Brugada 综合征（BS）患者的心脏事件通常发生在休息时，主要发生在睡眠中，这表明自主神经调节的变化在疾病的心律失常发生中起着重要作用。此外，BS 的临床表现存在性别差异，男性患者的预后较差。我们的工作旨在根据性别评估和比较包括 105 例 BS 患者在内的临床系列中的运动时自主神经反应。
在一项身体应激测试中收集标准 12 导联心电图记录，该测试分为四个阶段：热身、递增运动、主动恢复和被动恢复。通过平滑伪魏格纳-维尔分布方法提取频谱非平稳心率变异性指标，该方法使频带适应呼吸信息。然后，为每个患者在每个身体应激测试分钟的非重叠窗口中平均这些指标，以比较组间差异。
从热身的最后一分钟到递增运动的第三分钟，无症状男性患者的低频（LF）值显著更高（[Formula: see text]：p=0.015；[Formula: see text]：p=0.024；[Formula: see text]：p=0.011；[Formula: see text]：p=0.002）比无症状女性。相反，无症状女性在递增运动的前几分钟表现出增强的迷走神经调节（[Formula: see text]：p=0.031；[Formula: see text]：p=0.001）。然而，在有症状的男性和女性患者之间没有观察到显著差异。
正如先前在健康受试者中报道的那样，增强的副交感神经和减少的交感神经张力不仅在女性中更为明显，而且在心脏应激期间也具有防御性。根据结果，无症状患者表现出同性别倾向。然而，我们观察到有症状的男性发展出更女性化的自主神经调节，这可能与对运动的更保护性自主神经反应有关。这些结果可能是理解 Brugada 综合征自主功能的一个进步，并可能对危险分层产生影响。
