title: Flecainide versus digoxin for fetal supraventricular tachycardia: Comparison of two drug treatment protocols.
abstract: The optimal treatment for fetal supraventricular tachycardia (SVT) with 1:1 atrioventricular relationship is unclear.
  
  
  
  We compared the effectiveness of transplacental treatment protocols used in 2 centers.
  
  
  
  Pharmacologic treatment was used in 84 fetuses. Maternal oral flecainide was the primary therapy in center 1 (n = 34) and intravenous maternal digoxin in center 2 (n = 50). SVT mechanism was classified by mechanical ventriculoatrial (VA) time intervals as short VA or long VA. Treatment success was defined as conversion to sinus rhythm (SR), or rate control, defined as >15% rate reduction.
  
  
  
  Short VA interval occurred in 67 fetuses (80%) and long VA in 17 (20%). Hydrops was present 28 of 84 (33%). For short VA SVT, conversion to SR was 29 of 42 (69%) for digoxin and 24 of 25 (96%) for flecainide (P = .01). For long VA SVT, conversion to SR and rate control was 4 of 8 (50%) and 0 of 8, respectively, for digoxin, and 6 of 9 (67%) and 2 of 9 (cumulative 89%) for flecainide (P = .13). In nonhydropic fetuses, digoxin was successful in 23 of 29 (79%) and flecainide in 26 of 27 (96%) (P = .10). In hydrops, digoxin was successful in 8 of 21 (38%), flecainide alone in 6 of 7 (86%, P = .07 vs digoxin), and flecainide ± amiodarone in 7 of 7 (100%) (P = .01). Intrauterine or neonatal death occurred in 9 of 21 hydropic fetuses treated with digoxin (43%), compared to 0 of 7 (P = .06) treated with flecainide.
  
  
  
  Flecainide was more effective than digoxin, especially when hydrops was present. No adverse fetal outcomes were attributed to flecainide.
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom. Electronic address: shankar.sridharan@gosh.nhs.uk.
authors.forename: Shankar
authors.initials: S
authors.lastname: Sridharan
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom.
authors.forename: Ian
authors.initials: I
authors.lastname: Sullivan
authors.affiliation: University Hospital Motol, Prague, Czech Republic.
authors.forename: Viktor
authors.initials: V
authors.lastname: Tomek
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom.
authors.forename: Joanne
authors.initials: J
authors.lastname: Wolfenden
authors.affiliation: University Hospital Motol, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Škovránek
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom.
authors.forename: Robert
authors.initials: R
authors.lastname: Yates
authors.affiliation: University Hospital Motol, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Janoušek
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom.
authors.forename: Troy E
authors.initials: TE
authors.lastname: Dominguez
authors.affiliation: Great Ormond Street Hospital and Institute of Cardiovascular Sciences, UCL, London, United Kingdom; University Hospital Motol, Prague, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Marek
mesh_terms: D061605:Administration, Intravenous; D000284:Administration, Oral; D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000097:blood; D002985:Clinical Protocols; D004077:Digoxin / Q000008:administration & dosage* / Q000097:blood; D004452:Echocardiography; D004487:Edema / Q000150:complications; D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy*; D046128:Fetal Therapies / Q000379:methods; D005424:Flecainide / Q000008:administration & dosage* / Q000097:blood; D006801:Humans; D011247:Pregnancy; D012189:Retrospective Studies; D013617:Tachycardia, Supraventricular / Q000145:classification / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy*; D016216:Ultrasonography, Prenatal; D055815:Young Adult
chemical_list: D000889:Anti-Arrhythmia Agents; D004077:Digoxin; D005424:Flecainide
keywords: Fetal supraventricular tachycardia; Fetal ultrasound; Prenatal treatment