Conduction system disease in fetuses evaluated for irregular cardiac rhythm. Fetal Diagn Ther 2006;21(3):307-13
Date
04/08/2006Pubmed ID
16601344DOI
10.1159/000091362Scopus ID
2-s2.0-33645659535 (requires institutional sign-in at Scopus site) 47 CitationsAbstract
OBJECTIVES: To determine the prevalence of 1st and 2nd degree AV block in fetuses with an irregular cardiac rhythm, and to summarize outcome of these pregnancies.
BACKGROUND: The diagnosis of irregular cardiac rhythm or 'skipped beats' includes isolated ectopy that resolves spontaneously. Recently, Doppler measurements of the 'mechanical' PR interval have been shown to identify AV conduction disease prenatally. Prenatal therapy of these conduction abnormalities may limit the progression to more advanced disease either in utero or after birth.
METHODS: A retrospective review was performed of fetuses evaluated between 1996 and 2004 with the findings of irregular cardiac rhythm. 1st or 2nd degree AV block was diagnosed on Doppler and M-mode recordings, and confirmed using either fetal magnetocardiography (fMCG) or postnatal 12-lead ECG. Dexamethasone was administered to 4 mothers with abnormal fetal AV conduction in the setting of anti-Ro/anti-La antibodies.
RESULTS: Of 702 fetuses initially referred for arrhythmia, 306 had an irregular rhythm. Eight (2.6%) had intermittent 1st or 2nd degree AV block confirmed by fMCG and/or postnatal 12-lead ECG. AV block was presumed idiopathic in 2, associated with congenital long QT syndrome in 2 or with clinically unsuspected maternal anti-Ro or anti-La antibodies in 4. During the intrauterine period there was no progression to complete AV block and all were born alive at 34-40 weeks of gestation.
CONCLUSION: A small but clinically significant population of fetuses with irregular rhythm will have 1st or 2nd degree AV block. Transplacental therapy may limit the intrauterine progression to more advanced disease.
Author List
Cuneo BF, Strasburger JF, Wakai RT, Ovadia MAuthor
Janette F. Strasburger MD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AntibodiesAntibodies, Antinuclear
Arrhythmias, Cardiac
Autoantigens
Echocardiography
Female
Fetal Diseases
Heart Block
Heart Conduction System
Humans
Long QT Syndrome
Pregnancy
Pregnancy Complications
Retrospective Studies
Ribonucleoproteins