Twin-reversed arterial perfusion sequence: pre- and postoperative cardiovascular findings in the 'pump' twin

Ultrasound Obstet Gynecol. 2009 Nov;34(5):550-5. doi: 10.1002/uog.6431.


Objectives: To assess cardiovascular findings in twin-reversed arterial perfusion (TRAP) sequence pre- and post-therapy and compare these findings to traditional obstetric markers, defined as acardius to pump twin weight ratio and presence of polyhydramnios.

Methods: This was a retrospective review of 27 cases of TRAP sequence diagnosed between 2004 and 2008. Echocardiographic data included indexed cardiac output and functional and anatomic parameters. Ultrasound reports were reviewed for acardius to pump twin weight ratio and polyhydramnios. We assessed the relationship between cardiac output and the remaining cardiac/obstetric variables obtained pre- and post-treatment.

Results: Twenty-three subjects had complete echocardiographic data sets at initial evaluation (mean gestational age, 20.4 +/- 2.5 weeks) and, of these, post-treatment echocardiographic evaluation was available in 10. Six of seven (86%) pump twins with elevated indexed cardiac output had significant cardiovascular compromise. Most fetuses with abnormal cardiac output or right ventricular dysfunction normalized post-therapy. There was no relationship between cardiac output and obstetric markers.

Conclusions: Elevated indexed cardiac output is strongly associated with cardiovascular compromise. Traditional obstetric prognosticators do not correlate with cardiovascular derangements. In pump twins with cardiac compromise, postoperative cardiovascular status improves acutely. Given this analysis, we conclude that assessment of cardiovascular findings should be incorporated into the management and treatment of TRAP sequence.

MeSH terms

  • Cardiac Output / physiology*
  • Catheter Ablation / methods
  • Diseases in Twins / congenital
  • Diseases in Twins / diagnostic imaging*
  • Diseases in Twins / surgery
  • Female
  • Fetal Heart / abnormalities*
  • Fetal Heart / diagnostic imaging
  • Fetal Heart / surgery
  • Fetofetal Transfusion / diagnostic imaging*
  • Fetofetal Transfusion / embryology
  • Fetofetal Transfusion / surgery
  • Gestational Age
  • Heart Defects, Congenital / diagnostic imaging*
  • Heart Defects, Congenital / embryology
  • Heart Defects, Congenital / surgery
  • Humans
  • Polyhydramnios / diagnostic imaging*
  • Pregnancy
  • Retrospective Studies
  • Twins, Monozygotic
  • Ultrasonography, Prenatal