Delaney Jessica, Mittal Suneet, Sherrid Mark V
Division of Cardiology, Department of Medicine, St Luke's-Roosevelt Hospital Center, Columbia University, College of Physicians and Surgeons, New York, NY 10019, USA.
Anadolu Kardiyol Derg. 2009 Dec;9 Suppl 2:3-11.
Congenital long QT syndrome is a genetic disorder characterized by prolonged QT interval on electrocardiogram and increased risk of sudden cardiac death from ventricular arrhythmias. In long QT syndrome, genes that encode for the various cardiac ion channels or regulatory proteins of these channels are mutated. The various mutations individually lead to a disruption of the normal cardiac myocyte action potential, and thus leading to a propensity for ventricular arrhythmias. Diagnosis can be difficult with patient presentations ranging from palpitations to syncope to sudden cardiac death. The QT interval can also vary over time, often requiring further testing to support the diagnosis. Recently developed genetic testing can be used to identify the responsible genes in patients with known disease. It can also be used to genotype the affected patient's family members. The current test panel only recognizes common mutations resulting in a falsely negative test for those with a rare or unidentified variant. For treatment, beta-blocker therapy is recommended for all patients, and implantable cardioverter-defibrillator (ICD) placement is recommended for those who are at high risk for a cardiac event. Future investigations will concentrate genotype-guided risk stratification for ICD placement and on genotype-specific pharmacological therapy.
先天性长QT综合征是一种遗传性疾病，其特征为心电图上QT间期延长，以及因室性心律失常导致心脏性猝死的风险增加。在长QT综合征中，编码各种心脏离子通道或这些通道调节蛋白的基因发生突变。各种突变单独导致正常心肌细胞动作电位的破坏，从而导致室性心律失常的倾向。患者表现从心悸到晕厥再到心脏性猝死，诊断可能很困难。QT间期也会随时间变化，常常需要进一步检查以支持诊断。最近开发的基因检测可用于识别已知疾病患者的致病基因。它还可用于对受影响患者的家庭成员进行基因分型。目前的检测组仅识别常见突变，导致对具有罕见或未识别变异的患者检测结果呈假阴性。对于治疗，建议所有患者使用β受体阻滞剂治疗，对于心脏事件高危患者建议植入心脏复律除颤器（ICD）。未来的研究将集中于ICD植入的基因型指导风险分层以及基因型特异性药物治疗。
