F126Congenital complete atrio‐ventricular (AV) block. Prenatal diagnosis and perinatal outcome

Abstract

BackgroundThere are two types of complete heart AV block; associated and non associated with congenital heart malformations. The purpose of this work is to describe the ultrasound features and perinatal outcome of cases with prenatal diagnosis of complete AV block.MethodsA descriptive retrospective trial was performed. The AV block criteria were the presence of ventricular cardiac frequencies less than 80 bpm, and atria ventricular dissociation. In normal fetal heart group presence of Ro, Ssa and/or Ssb maternal antibodies were tested.ResultsThirteen cases of complete AV block were identified, 8 with structural malformations and five with normal cardiac structure but with presence of maternal antibodies. The patients average age was 23 years (range: 18–37), the gestational age at diagnosis was 25 weeks (range: 20–30). The ventricular frequency was 52 bpm (range: 42–73) and the atrial frequency was 112 bpm (range: 70–152). The cardiac malformations were present in 8 fetuses and the most frequent were the AV channel and single atria. Mortality in malformations cases was 100% and in those with immunological origin was about 40% (2/5). There were three survivors; two of them needed definitive heart peacemaker.ConclusionThe prognosis in the cases associated to structural malformations was always lethal, nevertheless in immunological origin cases prenatal diagnosis and perinatal management allowed the survival of them.