title: Foetal tachyarrhythmia treatment remains challenging even if the vast majority of cases have a favourable outcome.
abstract: OBJECTIVE
  The optimal treatment for foetal tachyarrhythmia remains controversial, and this study aimed to fill this gap in the knowledge.
  
  
  METHODS
  We retrospectively reviewed all cases of foetal tachyarrhythmia diagnosed at two tertiary foetal cardiology centres in Sweden from 1990 to 2012.
  
  
  RESULTS
  Of the 153 cases, 28% had atrial flutter (AF), 63% had atrioventricular reentrant tachycardia (AVRT) and 9% had other mechanisms. Hydrops was present in 45, less frequently in AF than in AVRT. Transplacental treatment was commenced in 99 and the rhythm normalised in two-thirds, without any significant difference in cardioversion rates between AF and AVRT cases or nonhydropic and hydropic foetuses. Sotalol treatment had a higher cardioversion rate than digoxin in AVRT (63% versus 33%, p < 0.05) but not in AF (57% versus 56%). Two or more drugs were used in 38%. Neonatal survival was 100% in nonhydropic and 84% in hydropic cases. After a median of eight years, 11/134 patients still had arrhythmias, one had died due to arrhythmia and another had undergone cardiac transplantation.
  
  
  CONCLUSIONS
  Transplacental treatment was frequently insufficient to obtain cardioversion in nonhydropic and hydropic foetuses, but all nonhydropic cases had favourable outcomes. Larger prospective studies are needed to optimise the treatment of cases with hydrops.
authors.affiliation: Paediatric Cardiology, Department of Women's and Children's Health, The Queen Silvia Children's Hospital, Gothenburg, Sweden.
authors.forename: Britt-Marie
authors.initials: BM
authors.lastname: Ekman-Joelsson
authors.affiliation: Paediatric Cardiology, Department of Women's and Children's Health, The Queen Silvia Children's Hospital, Gothenburg, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Mellander
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Linda
authors.initials: L
authors.lastname: Lagnefeldt
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Sven-Erik
authors.initials: SE
authors.lastname: Sonesson
mesh_terms: D005260:Female; D005315:Fetal Diseases / Q000188:drug therapy*; D046128:Fetal Therapies; D006801:Humans; D011247:Pregnancy; D012189:Retrospective Studies; D013610:Tachycardia / Q000188:drug therapy*; D016896:Treatment Outcome
keywords: Digoxin; Foetus; Gender; Sotalol; Tachyarrhythmia