背景:在所有胎儿心脏传导阻滞患者中,>50%的病例与母体自身免疫性疾病相关,这样的病人应该接受治疗。然而,近一半的胎儿心脏传导阻滞病例涉及自身免疫抗体筛查结果阴性的母亲。一些研究报道了长QT综合征(LQTS)也可以表现为严重的胎儿心动过缓,对胎儿治疗没有反应。在这里,我们报道了一例罕见的婴儿病例,该婴儿出现高度自身免疫介导的胎儿房室传导阻滞(AVB),并由新型KCNH2变异体诱导LQTS.此病例使我们回顾了我们的产前治疗策略。
方法:一个1岁的男孩出现在我们的心脏中心,在过去的一年中经历了5次晕厥。他以前在27+3孕周的胎儿期出现过胎儿心动过缓。胎儿超声心动图显示AVB(2:1透射)。由于母体自身抗体检测结果为阳性,他的母亲在怀孕期间接受了地塞米松治疗;随后,胎儿AVB已从2:1变为4:3传播,室性搏动率升高。然而,该患者在出生后被确定为完全AVB.医院管理部门的初始心电图和Holter测量显示完全AVB,多形性室性心动过速,延长的QT间隔(QT=602毫秒,校正QT=538ms),又宽又深的倒T波。同时,根据Holter监测检查,可以在几种过境室性心动过速中观察到扭转性室性心动过速。基因检测显示KCNH2c.2483G>A变体诱导的LQTS。植入式心律转复除颤器和永久性起搏器均被认为是治疗性的替代方案;他的父母最终接受了永久性起搏器的植入。
结论:对于患有自身免疫介导的AVB的胎儿,仍应立即进行宫内治疗。然而,一旦治疗结果被认为是不可接受的或出乎意料的,其他遗传变异相关的信道病应该高度怀疑。如果胎儿缺乏积极的家族史,应建议进行胎儿基因检测,通过在产前和产后阶段之间引入综合治疗策略来改善此类患者的预后.
Among all fetal heart block patients, > 50% cases are associated with maternal autoimmune diseases, and such patients should receive treatment. However, nearly half of fetal heart block cases involve a mother with negative results following autoimmune antibody screening. A few studies have reported long QT syndrome (LQTS) can also present as a severe fetal bradycardia, which does not respond to fetal treatment. Herein, we reported a rare case of an infant who presented with high-degree autoimmune-mediated fetal atrioventricular block (AVB) with LQTS induced by a novel KCNH2 variant. This case led us to review our prenatal therapeutic strategy.
A 1-year-old boy presented to our heart center having experienced syncope 5 times in the past year. He had previously presented with fetal bradycardia during the fetal stage from 27 + 3 gestational weeks. The fetal echocardiography demonstrated AVB (2:1 transmission). As the maternal autoimmune antibody results were positive, his mother had received dexamethasone treatment during pregnancy; subsequently, the fetal AVB had changed from 2:1 to 4:3 transmission with elevated ventricular beating rates. However, this patient was identified to have complete AVB after birth. The initial electrocardiogram and Holter measurements at hospital administration showed complete AVB, pleomorphic ventricular tachycardia, a prolonged QT interval (QT = 602 ms, corrected QT = 538 ms), and wide and deep inverted T-waves. Meanwhile, torsades de pointes could be observed in several transit ventricular tachycardias based on Holter monitoring review. Genetic testing revealed KCNH2 c.2483G > A variant-induced LQTS. An implantable cardioverter defibrillator device and permanent pacemaker were both considered as therapeutic alternations; his parents ultimately accepted the implantation of a permanent pacemaker.
For fetuses with autoimmune-mediated AVB, intrauterine treatment should still be pursued immediately. However, once the treatment outcomes are deemed unacceptable or unexpected, other genetic variant-related channelopathies should be highly suspected. If the fetus lacks a positive family history, fetal genetic testing should be recommended to improve the prognosis of such patients by introducing integrative therapeutic strategies between the prenatal and postnatal phases.