title: Prenatal diagnosis of a familial form of junctional ectopic tachycardia.
abstract: Junctional ectopic tachycardia (JET) is a rare cardiac arrhythmia characterized by atrio-ventricular dissociation, a high rate junctional escape rhythm and poor clinical tolerance in neonates and infants. Sudden infant death has been reported. The intra-uterine presentation of this arrhythmia is unknown. We report a familial form of JET with antenatal diagnosis. A sustained tachycardia at a rate of 170 beats/min with a 1:1 conduction was diagnosed in a hydropic fetus at a gestational age of 32 weeks. The older brother had presented with prenatal hydrops and junctional ectopic tachycardia was diagnosed at birth. Assuming that this arrhythmia was a JET, amiodarone was given to the mother in order to control the fetal tachycardia. The arrhythmia persisted with a 1/1 pattern but at a slower ventricular rate (140 beats/min). The ECG performed at birth revealed a narrow QRS tachycardia with a ventricular rate of 180 beats/min and a 1/1 retrograde conduction. Amiodarone therapy was continued with the addition of propanolol. Postnatal echocardiography revealed normal chambers and left ventricular dysfunction with a left ventricular shortening fraction of 17 per cent. Subsequent ECGs and Holter monitoring demonstrated typical electrocardiographic features of JET. Both parents had a normal ECG and Holter monitoring. A fetal tachycardia of moderately high rate with a 1/1 retrograde conduction and poor cardiac tolerance can be due to JET. In such cases, the use of amiodarone can be considered as a first line drug.
authors.affiliation: Paediatric Cardiology Department, Robert Debré Hospital, Paris, France. jean-marc.lupoglazof@rdb.ap-hop-paris.fr
authors.forename: J M
authors.initials: JM
authors.lastname: Lupoglazoff
authors.forename: I
authors.initials: I
authors.lastname: Denjoy
authors.forename: D
authors.initials: D
authors.lastname: Luton
authors.forename: S
authors.initials: S
authors.lastname: Magnier
authors.forename: A
authors.initials: A
authors.lastname: Azancot
mesh_terms: D000328:Adult; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D004562:Electrocardiography; D005260:Female; D005315:Fetal Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis; D013613:Tachycardia, Ectopic Junctional / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone