Francis Johnson, Sankar Vikram, Nair Venugopal Krishnan, Priori Silvia G
Department of Cardiology, Medical College Calicut, Kerala, India.
Heart Rhythm. 2005 May;2(5):550-4. doi: 10.1016/j.hrthm.2005.01.024.
Catecholaminergic polymorphic ventricular tachycardia (VT) is a rare arrhythmogenic disease characterized by exercise- or stress-induced ventricular tachyarrhythmias, syncope, or sudden death, usually in the pediatric age group. Familial occurrence has been noted in about 30% of cases. Inheritance can be autosomal dominant or recessive, usually with high penetrance. The causative genes have been mapped to chromosome 1. Mutations of the cardiac ryanodine receptor gene (RyR2) have been identified in autosomal dominant pedigrees, while calsequestrin gene (CASQ2) mutations are seen in recessive cases. Ankyrin-B mutations may also be implicated in catecholaminergic polymorphic VT: mutations in this gene were previously linked to the long-QT 4 phenotype. Ventricular ectopy, bidirectional VT, and polymorphic VT occur in a predictable and progressive manner with increasing heart rate during exercise or isoproterenol infusion. Estimated mortality of untreated cases ranges from 30% to 50% before the age of 20-30 years according to family studies. Although beta-blocker therapy was considered to be effective in preventing clinical recurrence in the initial series, recent data show low efficacy. As there is a chance for sudden cardiac death if even a single dose of beta-blocker is missed, there is a trend toward implantation of defibrillators in more and more patients.
儿茶酚胺能多形性室性心动过速（VT）是一种罕见的致心律失常疾病，其特征为运动或应激诱发的室性快速心律失常、晕厥或猝死，通常发生于儿童年龄组。约30%的病例有家族发病情况。遗传方式可为常染色体显性或隐性，通常具有高外显率。致病基因已被定位到1号染色体。在常染色体显性谱系中已鉴定出心脏雷诺丁受体基因（RyR2）的突变，而隐性病例中可见肌集钙蛋白基因（CASQ2）突变。锚蛋白B突变也可能与儿茶酚胺能多形性室性心动过速有关：该基因的突变先前与长QT 4表型相关。在运动或静脉输注异丙肾上腺素期间，随着心率增加，室性早搏、双向室性心动过速和多形性室性心动过速以可预测和渐进的方式发生。根据家族研究，未经治疗的病例在20至30岁之前的估计死亡率为30%至50%。尽管在最初的系列研究中，β受体阻滞剂治疗被认为对预防临床复发有效，但最近的数据显示其疗效较低。由于即使漏服一剂β受体阻滞剂也有心脏性猝死的风险，越来越多的患者有植入除颤器的趋势。
