Division of Cardiology, Electrophysiology, Toronto General Hospital University Health Network Toronto Toronto Ontario Canada.
Division of Cardiology The Hospital for Sick Children Toronto Ontario Canada.
J Am Heart Assoc. 2023 Dec 5;12(23):e029407. doi: 10.1161/JAHA.122.029407. Epub 2023 Nov 28.
It has been postulated that long QT syndrome (LQTS) can cause fetal loss through putative adverse effects of the channelopathy on placenta and myometrial function. The authors aimed to describe the fetal death rate in a population of pregnant women with long QT syndrome and investigate whether women with more severe phenotype had worse fetal outcomes.
The authors retrospectively evaluated fetal outcomes of 64 pregnancies from 23 women with long QT syndrome followed during pregnancy in a tertiary pregnancy and heart disease program. Thirteen of 64 pregnancies (20%) resulted in a fetal loss, 12 miscarriages (19%), and 1 stillbirth (1.6%). Baseline maternal characteristics, including age and use of β-blockers, did not differ between women who experienced a fetal death or not. Maternal corrected QT interval (QTc) was significantly longer in pregnancies that resulted in fetal death compared with live births (median, 518 ms [interquartile range (IQR), 482-519 ms] versus 479 ms [IQR, 454-496 ms], <0.001). Mothers treated with β-blockers had babies born at term with lower birth weight compared with untreated women (2973±298 g versus 3470±338 g, =0.002). In addition, the birth weight of babies born at term to treated women with QTc >500 ms was significantly lower compared with women with QTc <500 ms (2783±283 g versus 3084±256 g, =0.029).
Women with long QT syndrome with more severe phenotypes have a higher incidence of fetal death. Maternal QTc is longer in pregnancies that result in fetal loss, and the birth weight of babies born to patients taking β-blockers with a QTc >500 ms is lower, suggesting that patients with more marked phenotype may experience worse fetal outcomes.
据推测，长 QT 综合征（LQTS）可能通过通道病对胎盘和子宫肌功能的潜在不良影响导致胎儿丢失。作者旨在描述长 QT 综合征孕妇人群中的胎儿死亡率，并探讨表型更严重的女性是否存在更差的胎儿结局。
作者回顾性评估了在三级妊娠和心脏病计划中接受孕期监测的 23 名长 QT 综合征女性的 64 例妊娠的胎儿结局。64 例妊娠中有 13 例（20%）导致胎儿丢失，12 例流产（19%），1 例死胎（1.6%）。经历胎儿死亡或未经历胎儿死亡的女性之间的基线孕产妇特征，包括年龄和β受体阻滞剂的使用，并无差异。与存活分娩相比，导致胎儿死亡的妊娠中母亲校正 QT 间期（QTc）明显更长（中位数，518 ms [四分位距（IQR），482-519 ms] 与 479 ms [IQR，454-496 ms]，<0.001）。与未接受治疗的女性相比，接受β受体阻滞剂治疗的女性所生婴儿出生时体重更轻，但足月（2973±298g 与 3470±338g，=0.002）。此外，接受β受体阻滞剂治疗且 QTc>500 ms 的女性所生足月婴儿的出生体重明显低于 QTc<500 ms 的女性（2783±283 g 与 3084±256 g，=0.029）。
表型更严重的长 QT 综合征女性胎儿死亡率更高。导致胎儿丢失的妊娠中母亲 QTc 更长，服用 QTc>500 ms 的β受体阻滞剂的患者所生婴儿的出生体重较低，这表明表型更明显的患者可能会经历更差的胎儿结局。
