长时间QT综合征和torsade de pointes的发生
1Department of Cardiology, Sourasky-Tel Aviv Medical Center, and Sackler-School of Medicine, Tel Aviv University, Israel. viskin_s@netvision.net.il
Lancet (London, England)
|November 24, 1999
概括
长QT综合征 (LQTS) 涉及离子通道功能障碍,导致危险的心律,如torsade de pointes. 遗传突变和药物等外部因素都可能导致LQTS,随着对易受影响的个体的认识越来越多.
科学领域:
- 心脏病学 心脏病学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 长QT综合征 (LQTS) 的特征是心室再极化受损,导致潜在的致命性心律失常,如torsade de pointes.
- LQTS的症状,包括昏迷和心脏骤停,直接与这种特定的腹腔动脉节律失常有关.
- LQTS可能是先天的,源于离子通道基因的遗传突变,或是由于药物或代谢问题而获得的.
研究的目的:
- 审查目前对长QT综合征的理解,包括先天性和获得的形式.
- 讨论先天性LQTS的遗传基础以及与临床表现和治疗策略相关联的基因型的持续努力.
- 突出涉及获得LQTS的药物清单不断扩大,并确定药物诱导的torsades de pointes的风险因素和警告标志.
主要方法:
- 关于长QT综合征,遗传突变和药物诱导的心律失常的现有文献的审查.
- 对已识别的基因型 (LQT1至LQT6) 及其临床相关性的分析.
- 检查与获得的LQTS相关的风险因素和心电图征兆.
主要成果:
- 已经确定了6种先天性LQTS基因型,目前正在进行研究,以将特定突变与临床结果和治疗方法联系起来.
- 获得的LQTS越来越多地被认可,通常是由影响离子通道功能的药物触发的.
- 药物诱导的torsades de pointes的危险因素,包括女性性别,最近的心率减慢和低血压,以及特定的心电图警告标志.
- 新出现的证据表明,在获得LQTS的患者中,潜在的潜在倾向性导致前节律失常.
- 识别"沉默"的先天性LQTS突变,这些突变只在暴露于反极化延迟药物时才使个体易患心律失常.
结论:
- 长QT综合征代表了一系列由离子通道功能障碍引起的疾病,对心律失常风险有重大影响.
- 了解LQTS的遗传基础和获得的触发因素对于风险分层和个性化治疗方法至关重要.
- 对遗传倾向和药物相互作用的进一步研究是有必要的,以改善与LQTS相关事件的管理和预防.
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