Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
Europace. 2010 Apr;12(4):544-52. doi: 10.1093/europace/eup432. Epub 2010 Jan 17.
This study sought to examine the action potential duration restitution (APDR) property and conduction delay in Brugada syndrome (BrS) patients. A steeply sloped APDR curve and conduction delay are known to be important determinants for the occurrence of ventricular fibrillation (VF).
Endocardial monophasic action potential was obtained from 39 BrS patients and 9 control subjects using the contact electrode method. Maximum slopes of the APDR curve were obtained at both the right ventricular outflow tract (RVOT) and the right ventricular apex (RVA). The onset of activation delay (OAD) after premature stimulation was examined as a marker of conduction delay. Maximum slope of the APDR curve in BrS patients was significantly steeper than that in control subjects at both the RVOT and the RVA (0.77 +/- 0.21 vs. 058 +/- 0.14 at RVOT, P = 0.009; 0.98 +/- 0.23 vs. 0.62 +/- 0.16 at RVA, P = 0.001). The dispersion of maximum slope of the APDR curve between the RVOT and the RVA was also larger in BrS patients than in control subjects. The OAD was significantly longer in BrS patients than in control subjects from the RVOT to RVA and from the RVA to RVOT (from RVOT to RVA: 256 +/- 12 vs. 243 +/- 7 ms, P = 0.003; from RVA to RVOT: 252 +/- 11 vs. 241 +/- 9 ms, P = 0.01).
Abnormal APDR properties and conduction delay were observed in BrS patients. Both repolarization and depolarization abnormalities are thought to be related to the development of VF in BrS patients.
本研究旨在探讨 Brugada 综合征（BrS）患者的动作电位时程复极（APDR）特性和传导延迟。众所周知，陡峭的 APDR 曲线和传导延迟是心室颤动（VF）发生的重要决定因素。
使用接触电极法从 39 名 BrS 患者和 9 名对照受试者中获得心内膜单相动作电位。在右心室流出道（RVOT）和右心室心尖（RVA）获得 APDR 曲线的最大斜率。作为传导延迟的标志物，检查过早刺激后的激活延迟（OAD）。BrS 患者的 APDR 曲线最大斜率在 RVOT 和 RVA 均明显比对照组陡峭（RVOT 处为 0.77 +/- 0.21 对 0.58 +/- 0.14，P = 0.009；RVA 处为 0.98 +/- 0.23 对 0.62 +/- 0.16，P = 0.001）。RVOT 和 RVA 之间的 APDR 曲线最大斜率的离散度在 BrS 患者中也大于对照组。从 RVOT 到 RVA 和从 RVA 到 RVOT，BrS 患者的 OAD 明显长于对照组（从 RVOT 到 RVA：256 +/- 12 对 243 +/- 7 ms，P = 0.003；从 RVA 到 RVOT：252 +/- 11 对 241 +/- 9 ms，P = 0.01）。
BrS 患者存在异常的 APDR 特性和传导延迟。复极和去极化异常均被认为与 BrS 患者 VF 的发生有关。
