Fetal atrioventricular block and postpartum augmentative QT prolongation in a patient with long-QT syndrome with KCNQ1 mutation.
The case of a 32-year-old pregnant woman, who had had several syncopal episodes during swimming and running at 9 and 10 years of age and whose fetus had 2:1 AV block, is presented. The mother and baby had the same heterozygous single nucleotide substitution in KCNQ1 at T587M. After 27 weeks of gestation, the fetal 2:1 AV block disappeared, and 1:1 AV conduction resumed, with a fetal heart rate of 110-120 beats/min. The maternal electrocardiogram revealed a normal QTc interval (433 ms) without ST-T abnormalities at gestational week 23, but the QTc was 490 and 531 ms at 1 and 2 months postpartum, with biphasic T waves in leads V2 and V3. This case is the first report of fetal 2:1 AV block with KCNQ1 mutation (T587M) and unmasked maternal QT prolongation in the postpartum period.
Furushima
Hiroshi
H
First Department of Internal Medicine, Niigata University School of Medicine, Asahimachi-dori, Niigata, Japan. chimiri@med.niigata-u.ac-jp
Chinushi
Masaomi
M
Sato
Akinori
A
Aizawa
Yoshifusa
Y
Kikuchi
Akira
A
Takakuwa
Koichi
K
Tanaka
Kenichi
K
D000328:Adult; D054537:Atrioventricular Block / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D051656:KCNQ Potassium Channels / Q000235:genetics*; D008133:Long QT Syndrome / Q000150:complications / Q000175:diagnosis* / Q000235:genetics*; D011247:Pregnancy
D051656:KCNQ Potassium Channels