目的:总结n CASQ2基因变异致儿童儿茶酚胺敏感性多形性室性心动过速(CPVT)的临床特征及遗传学特点。n 方法:回顾性分析2017年1月至2018年11月在首都医科大学附属北京儿童医院诊治的8例(男女各4例)n CASQ2基因变异阳性CPVT患儿的临床资料，基因检测采用靶向高通量二代测序法，并通过Sanger进行家系成员验证。n 结果:8例患儿平均发病年龄为6.4岁，平均确诊年龄为9.4岁，平均诊断周期为3年；仅2例首次发病即确诊，余6例均存在延迟诊断，其中3例误诊为癫痫。8例患儿均存在运动或情绪激动后出现晕厥，持续几分钟可自行恢复意识，无猝死病史及家族史。发作间期静息心电图6例未见异常，2例有轻度窦性心动过缓。动态心电图及平板运动试验记录到典型的双向性和/或多形性室性心动过速的病例数分别为8/8例、5/5例。患儿均存在n CASQ2基因变异，6例为复合杂合变异，2例为纯合变异。8例患儿共检测到9个n CASQ2基因变异位点，其中5个为未报道的新变异。经家系验证，8例患儿均为家族遗传性变异，无新发变异。8例患儿均予β受体阻滞剂口服治疗，无症状反复发作。平均随访1.5年，1例患儿因严重窦性心动过缓植入心脏复律除颤器，无死亡病例。n 结论:CASQ2基因变异所致儿童CPVT，绝大多数在学龄前期起病，表现为运动或情绪激动后反复晕厥，双向性和/或多形性室性心动过速为其突出特点。延迟诊断和误诊较普遍，β受体阻滞剂治疗具有较好有效性和安全性。5个新变异丰富了n CASQ2的基因突变谱。n “,”Objective:To summarize the clinical and genetic characteristics of catecholaminergic polymorphic ventricular tachycardia (CPVT) in children caused by n CASQ2 gene variants.n Methods:The clinical data of 8 children (4 males and females, respectively) with CPVT caused by n CASQ2 gene variants admitted to Beijing Children′s Hospital, Capital Medical University from January 2017 to November 2018 were retrospectively analyzed.The targeted next generation sequencing was employed to identify n CASQ2 variants and Sanger sequencing was conducted to conform the candidate variants and determine the parental origin.n Results:As for 8 children in this study, the average age of onset was 6.4 years, the mean age at diagnosis was 9.4 years, and the average interval from onset to diagnosis was 3 years.Only 2 cases had clearly diagnosis at onset, other 6 cases had a delay to diagnosis and 3 cases of them were diagnosed at other hospitals as having epilepsy and did not respond to anti-epileptic therapy.During physical activity and/or emotional stress, 8 cases presented with recurrent syncope and were able to regain consciousness after a few minutes.They had no a history of sudden cardiac death or family history.There was no abnormality on resting electrocardiogram during the paroxysmal interval in 6 cases and mild sinus bradycardia in 2 cases.Typical bidirectional ventricular tachycardia (VT) and/or polymorphic VT were detected in 8/8 cases and 5/5 cases, respectively, based on Holter electrocardiography and cardiac stress test.The n CASQ2 gene variant was found in all children, with 6 cases carrying compound heterozygous variants and 2 cases carrying homozygous variants.A total of 9 different n CASQ2 variants were detected in 8 cases, of which 5 had not been previously reported.According to the family-line verification, all of them had a familial variant, with no novel variants.All 8 cases were treated orally with β-blockers, with asymptomatically recurrent episodes, with a mean follow-up of 1.5 years, during which implantable cardioverter defibrillation was performed in 1 case owing to severe sinus bradycardia.There was no death case among them.n Conclusions:CPVT with n CASQ2 variants is characterized by early onset before preschool age, recurrent syncope after exercise or emotional stress and bidirectional/polymorphic VT.Early diagnosis of CPVT remains challenging due to delayed diagnosis or misdiagnosis.Treatment with β-blockers can achieve favorable effectiveness and safety.Five novel variants in this study would further expand the database of n CASQ2 genes.n