Donald School Journal of Ultrasound in Obstetrics and Gynecology

Register      Login

VOLUME 3 , ISSUE 2 ( April-June, 2009 ) > List of Articles


Fetal Arrhythmias: A Clinical Review

Zoltan Papp, Ágnes Harmath, Barbara Pete, Julia Hajdu, Valeria Váradi

Keywords : Fetal arrhythmias,Doppler,follow-up

Citation Information : Papp Z, Harmath Á, Pete B, Hajdu J, Váradi V. Fetal Arrhythmias: A Clinical Review. Donald School J Ultrasound Obstet Gynecol 2009; 3 (2):25-37.

DOI: 10.5005/jp-journals-10009-1012

License: CC BY-NC 4.0

Published Online: 01-03-2010

Copyright Statement:  Copyright © 2009; The Author(s).


Fetal rhythm abnormalities occur in 2% of pregnancies. They are usually identified by the obstetrician or midwifes after 20 weeks. There are four different methods used to assess fetal arrhythmias: scalp electrodes attached to electrocardiographic recordings, magnetocardiography (FMCG), fetal electrocardiographic recordings from the maternal abdomen, and fetal echocardiography (M-mode, pulsed-Doppler, Tissue-Doppler). In everyday practice the Doppler method was found to be the most useful method in the diagnosis and therapy of fetal arrhythmias. Doppler derived mechanical PR interval raised the possibility of refining the prenatal diagnosis of AV conduction abnormalities. A PR interval of >150 ms on Doppler, FMCG or postnatal ECG has been determined to be prolonged. Extrasystoles are most common cause of fetal arrhythmias, and are most often premature atrial contractions (PACs), what are usually identified in third trimester fetuses and their frequency may be highly variable. These are usually benign, resolving just before or shortly after birth. The follow-up is necessary, because some (1-3%) of affected fetuses have intermittent runs of supraventricular tachycardia. Ventricular tachycardia is rare during fetal life. With echocardiography in the setting of fetal tachycardia the findings of atrioventricular dissociation with a ventricular rate that is faster than the atrial rate suggests ventricular tachycardia. If there is 1:1 retrograde conduction it is impossible to distinguish between ventricular and supraventricular tachycardia. Atrial flutter accounted for 26.2% of all cases of fetal tachyarrhythmias and supraventricular tachycardia for 73.2%. Fouron and coworkers proposed to plan the management of the fetal tachyarrhythmia based on analysis of pulsed-Doppler recordings of fetal heart's blood flow. They determined short V-A tachycardia, when V-A (ventriculoatrial period) was shorter than AV (atrio-ventricular period) period. In the therapy of fetal supraventricular tachycardia there are different protocols, the most commonly used drugs are: digoxin, sotalol, amiodarone, flecainide. Persistent fetal sinus bradycardia is a rare condition and has been reported with central nervous system abnormalities, maternal treatment with beta blockers, excessive vagal tone, hydrops, long QT syndrome, intrauterine growth retardation and could be a sign of maternal anti-SSA/Ro antibodies. Prenatal sinus bradycardia or recognition of 2nd degree AV block may lead to early detection and treatment of long QT syndrome. Early detection of incomplete AV block, in cases of maternal anti SSA, SSB autoantibodies, successfully identifies a group at highest risk developing permanent AV block. The anti-inflammatory effects of dexamethasone might have interrupted on-going damage of the conduction system secondary to maternal autoantibodies. If the fetal arrhythmia resulted fetal hydrops, the mortality is high and the risk of late neurological morbidity must be taken into consideration. As a result of close follow-up, transplacentar treatment and well-organized perinatal management, the survival of sustained fetal arrhythmia significantly improved (50% versus 15%).

PDF Share
  1. Molecular embryogenesis of the heart. Pediatric and Developmental Pathology 2002;5:516-43.
  2. Basics of cardiac development for the understanding of comgenital heart malformations. Pediatric Research 2005;57:169-76.
  3. Rhythm abnormalities of the fetus. Heart 2007;93:1294-1300.
  4. Fetal cardiac repolarisation abnormalities. Am J Cardiol 2006;98:491-96.
  5. Standardisation of the PQRST waveform and analysis of arrhythmias in the fetus using vector magnetocardiography. Pediatric Research 2006;59:121-25.
  6. Magnetocardiographic rhythm patterns at initiation and termination of fetal supraventricular tachycardia. Circulation 2003;107:307-12.
  7. Fetal ECG: A novel predictor of atrioventricular block an anti- Ro positive pregnancies. Heart 2007;93:1454-60.
  8. Noninvasive fetal electrocardiography in sinleton and multiple pregnancies BJOG 2003;110:668-78.
  9. Comparison of Doppler and M-mode ultrasonography to time fetal atrial and ventricular contractions. Obstet Gynecol 2000;96:732-36.
  10. Manegement of fetal tachyarrhythmia based on superior vena cava/aorta Doppler flow recordings. Heart 2003;89:1211-06.
  11. Pulsed Doppler assessment of the fetal PR interval. Am J of Cardiol 2000;86:236-39.
  12. Reference values for time intervals between atrial and ventricular contractions of the fetal heart measured by two Doppler techniques. Am J of Cardiol 2001;88:1433-1636.
  13. Evaluation of fetal arrhythmias from simultaneous pulsed wave Doppler in pulmonary artery and vein. Heart 2007;93:1448-53.
  14. Doppler echocardiographic and Electrocardiographic atrioventricular time intervals in newborn infants: Evaluation of techniques for surveillance of fetuses at risk for congenital heart block. Ultrasound Obstet Gynecol 2006;28:57-62.
  15. conduction system disease in fetuses evaluated for irregular cardiac rhythm. Fetal Diagn Ther 2006;21:307-13.
  16. Assessment of fetal atrioventricular time intervals by tissue Doppler and pulse Doppler echocardiography: Normal values and correlation with fetal electrocardiography. Heart 2006;92:1830-37.
  17. Use of tissue velocity imaging in the diagnosis of fetal cardiac arrhythmias Circulation 2002;106:1827-33.
  18. Prenatal diagnosis and in utero treatment of torsades de pointes associated with congenital long QT syndrome. Am J of Cardiol 2003;91:1395-98.
  19. Irregular peak-to-peak intervals between ascending aortic flows during fetal ventricular tachycardia in long QT syndrome. Ultrasound Obstet Gynecol 2009;33:990-92.
  20. Antiarrhythmic drugs in pregnancy Curr Opin Cardiol 2001;16:40-45.
  21. Review of diagnosis, treatment, and outcome of fetal atrial flutter compared with supraventricular tachycardia. Heart 2003;89:913-17.
  22. Treatment of fetal tachycardia with sotalol: transplacental pharmacokinetics and pharmacodynamics. J Am Coll Cardiol 2003;4:765-70.
  23. Neonatal ECG changes caused by supratherapeutic flecainide following treatment for fetal supraventricular tachycardia. Heart 2003;89:470.
  24. Fetal tachycardias: Management and outcome of 127 consecutive cases Heart 1198;79:576-81.
  25. Neonatal cholestasis associated with fetal arrhythmia. J Pediatr 2005;146:277-80.
  26. Atrial flutter in the perinatal age group: Diagnosis, management and outcome. J Am Coll Cardiol 2000;35:771-77.
  27. Neonatal atrial flutter: Significant early morbidity and excellent long-term prognosis. Am Heart Journal 1997;133:302-06.
  28. Familial atrial fibrillation with fetal onset. Heart 1998;79:195-97.
  29. Long-term outcome in fetuses with cardiac arrhythmias. Obstet Gynecol 2003;102:1372-79.
  30. Echocardiographic assessment of fetal arrhythmias Heart 2007;93:1331-33.
  31. Novel molecular mechanism involving alfa 1D L-type calcium channel in autoimmune-associated sinus bradycardia Circulation 2005;111:3034-41.
  32. From antibody insult to fibrosis in neonatal lupus – the heart of the matter Arthritis Res Ther 2003;5:266-70.
  33. Signs of first-degree heart block occur in one-third of fetuses of pregnant women with anti-SSA/Ro 52-kd antibodies. Arhritis and Rheumatism 2004;50:1253-61.
  34. Utility of cardiac monitoring in fetuses at risk for congenital heart block. Circulation 2008;117:485-93.
  35. Outcome of children with fetal, neonatal or childhood diagnosis of isolated congenital atrioventricular block. J Am Coll Cardiol 2002;39:130-37.
  36. Pregnancy and autoimmunity: Maternal treatment and maternal disease influence on pregnancy outcome. Autoimmunity Reviews 2005;4:423-28.
  37. Hydrocephalus and macrocephaly: New manifestations of neonatal lupus erythematosus. Arthritis and Rheumatism 2007;57:261-66.
  38. Endocardial fibroelastosis associated with maternal anti- Ro and anti-La antibodies int he absence of atrioventricular block. J Am Coll Cardiol 2002;40:796-802.
  39. Congenital heart block: Development of late-onset cardiomyopathy, a previously inderappreciated sequela. J Am Coll Cardiol 2001;37:238-42.
  40. Autoimmune associated congenital heart block: Demographics, mortality, morbidity and recurrence rates obtained from a national neonatal lupus registry. J Am Coll Cardiol 1998;31:1658-66.
PDF Share
PDF Share

© Jaypee Brothers Medical Publishers (P) LTD.