Herreman G, Sauvaget F, Généreau T, Galezowski N
Service de Médecine Interne, Hôpital Saint-Joseph, Paris.
Ann Med Interne (Paris). 1990;141(3):234-8.
Congenital heart block is rare; it is acquired in utero, definitive and, more often than not, complete. It can be diagnosed by the appearance of fetal bradycardia around the 23rd week of gestation, during ultrasonographic monitoring of pregnancy. Heart block is usually associated with the presence of anti-Ro and/or anti-La antibodies in the mother's serum. These maternal immunological abnormalities can be isolated or associated with an autoimmune disease, usually systemic lupus erythematosus, but also Sjögren's syndrome, or more rarely still, an as yet unclassified connective tissue disease. Anti-Ro and anti-La antibodies cross the placental barrier and react with a fetal heart, leading to acute fetal myocarditis by the 17th week of gestation. When severe, it is lethal, otherwise it can result in degeneration and endocardial fibroelastosis, disrupting conduction and leading to congenital heart block. The ideal treatment would be prevention with corticosteroids. When the mother is Ro or La antibody-positive before pregnancy, elimination of these circulating antibodies can be attempted by treatment with 0.5 mg/kg body wt/d of prednisolone for 3 months. If the treatment is successful, corticotherapy can be prescribed early in the pregnancy to try to protect the fetus. However, there is not always a relationship between maternal anti-Ro antibodies and fetal heart block. If the Ro/La antibody-positive woman is already pregnant, but before her 17th week, it is possible to prescribe dexamethasone, which crosses the placenta and remains active, sometimes in association with plasmapheresis.
先天性心脏传导阻滞较为罕见；它是在子宫内获得的，通常是完全性的。在孕期超声监测时，可通过妊娠23周左右胎儿心动过缓的表现来诊断。心脏传导阻滞通常与母亲血清中存在抗Ro和/或抗La抗体有关。这些母体免疫异常可能是孤立存在的，也可能与自身免疫性疾病相关，通常是系统性红斑狼疮，也可为干燥综合征，或更罕见的是一种尚未分类的结缔组织病。抗Ro和抗La抗体穿过胎盘屏障并与胎儿心脏发生反应，在妊娠17周前导致急性胎儿心肌炎。病情严重时可致命，否则可导致变性和心内膜弹力纤维增生症，扰乱传导并导致先天性心脏传导阻滞。理想的治疗方法是用皮质类固醇进行预防。当母亲在妊娠前抗Ro或抗La抗体呈阳性时，可尝试用泼尼松龙按0.5毫克/千克体重/天的剂量治疗3个月，以消除这些循环抗体。如果治疗成功，可在妊娠早期给予皮质激素疗法以保护胎儿。然而，母体抗Ro抗体与胎儿心脏传导阻滞之间并不总是存在关联。如果抗Ro/La抗体阳性的女性已经怀孕，但在妊娠17周之前，可给予地塞米松，它可穿过胎盘并保持活性，有时可联合血浆置换疗法。
