Nguyen Dustin, Ferns Sunita J
School of Medicine, Eastern Virginia Medical School, 825 Fairfax Ave, Norfolk, VA, USA.
Department of Paediatrics, School of Medicine, University of North Carolina at Chapel Hill, 101 Manning Drive, Chapel Hill, NC, USA.
Eur Heart J Case Rep. 2018 Jul 17;2(3):yty083. doi: 10.1093/ehjcr/yty083. eCollection 2018 Sep.
Andersen-Tawil syndrome (ATS) is a rare arrhythmia disorder caused by a mutation in the KCNJ2 gene. Typical presentation includes a triad of cardiac arrhythmia, dysmorphia, and periodic paralysis. However, KCNJ2 mutations can mimic other disorders such as catecholaminergic polymorphic ventricular tachycardia (CPVT) making treatment challenging.
A 9-year-old asymptomatic female patient presented with an irregular heart rate noted at a well-child visit. Physical examination revealed short stature and facial dysmorphism. An initial rhythm strip showed intermittent runs of non-sustained bidirectional ventricular tachycardia with a prolonged QT interval of 485 ms at rest. Exercise testing showed no significant increase in ectopy from baseline at higher heart rates. Cardiac imaging was normal, and the burden of ventricular ectopy was significantly reduced on a beta-blocker and Class IC antiarrhythmic combination. Genetic testing marked a D71N mutation in the KCNJ2 gene.
Clinical distinction between ATS and CPVT is a challenge. Genetic testing in the above patient attributed a likely pathogenic variant for both ATS and CPVT to a single D71N mutation in the KCNJ2 gene. Further evaluation revealed no clinical CPVT, emphasizing the need for cautious interpretation of genetic results in inherited arrhythmia disorders.
安德森-塔维尔综合征（ATS）是一种由KCNJ2基因突变引起的罕见心律失常疾病。典型表现包括心律失常、畸形和周期性麻痹三联征。然而，KCNJ2基因突变可模拟其他疾病，如儿茶酚胺能多形性室性心动过速（CPVT），这使得治疗具有挑战性。
一名9岁无症状女性患者在儿童健康检查时被发现心率不规则。体格检查发现身材矮小和面部畸形。最初的心电图记录显示间歇性非持续性双向室性心动过速，静息时QT间期延长至485毫秒。运动试验显示，在较高心率下，异位搏动较基线无显著增加。心脏成像正常，使用β受体阻滞剂和I类C型抗心律失常药物联合治疗后，室性异位搏动负担显著减轻。基因检测发现KCNJ2基因存在D71N突变。
ATS和CPVT的临床鉴别具有挑战性。上述患者的基因检测将一个可能导致ATS和CPVT的致病变异归因于KCNJ2基因中的单个D71N突变。进一步评估未发现临床CPVT，强调在遗传性心律失常疾病中对基因检测结果进行谨慎解读的必要性。
