title: Effect of selective fetoscopic laser photocoagulation therapy for twin-twin transfusion syndrome on pulmonary valve pathology in recipient twins.
abstract: OBJECTIVE
  To investigate the impact of selective fetoscopic laser photocoagulation (SFLP) on pre-existing pulmonary valve pathology in the recipient twin in twin-twin transfusion syndrome (TTTS).
  
  
  METHODS
  We evaluated preoperative echocardiograms of all pregnancies with TTTS treated with SFLP at our institution from 2001 to 2009 (n = 76). Sixteen (21%) recipients had an abnormal pulmonary valve (stenosis/dysplasia, insufficiency or functional atresia) before SFLP. Postoperative echocardiograms and medical records from these 16 recipients were reviewed. Changes in pulmonary valve structure and function, and overall cardiac function, were noted after SFLP.
  
  
  RESULTS
  The mean gestational age at SFLP was 21 (range, 18.7-24.3) weeks. Seven of sixteen (44%) recipients with abnormal pulmonary valve prior to SFLP survived. Six of the 16 (37.5%) recipient twins had documented absence of persistent pulmonary valve abnormalities at birth or at autopsy. Two (12.5%) of the 16 recipients (2.6% of the original cohort) had persistent pulmonary valve abnormalities at birth, requiring intervention. Systolic and diastolic function improved or normalized after SFLP in all patients undergoing longitudinal follow-up. There was a tendency for a better cardiovascular profile score (best = 10 points) at initial evaluation in pregnancies with survivors compared with those with no survivors (mean (SD): 5.6 (2.2) vs. 6.75 (1.28)), but this was not statistically significant. Severity of cardiac involvement did not predict persistence of valve pathology or survival.
  
  
  CONCLUSIONS
  SFLP can improve flow through the pulmonary valve of the recipient twin in TTTS, probably as a consequence of improvements in right ventricular systolic and diastolic function. However, pulmonary valve pathology may persist and require postnatal intervention.
authors.affiliation: Pediatric Cardiology, University of California San Francisco, San Francisco, CA, USA. anita.moongrady@ucsf.edu
authors.forename: A J
authors.initials: AJ
authors.lastname: Moon-Grady
authors.forename: L
authors.initials: L
authors.lastname: Rand
authors.forename: B
authors.initials: B
authors.lastname: Lemley
authors.forename: K
authors.initials: K
authors.lastname: Gosnell
authors.forename: L K
authors.initials: LK
authors.lastname: Hornberger
authors.forename: H
authors.initials: H
authors.lastname: Lee
mesh_terms: D004452:Echocardiography / Q000379:methods; D005260:Female; D005330:Fetofetal Transfusion / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D005332:Fetoscopy; D005865:Gestational Age; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D017075:Laser Coagulation / Q000379:methods*; D016104:Oligohydramnios / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D011247:Pregnancy; D011664:Pulmonary Valve / Q000000981:diagnostic imaging / Q000196:embryology / Q000601:surgery*; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D014481:United States