title: Percutaneous closure of atrial right-to-left shunt in patients with Ebstein's anomaly of the tricuspid valve.
abstract: OBJECTIVE
  Patients with Ebstein's anomaly of the tricuspid valve may have right-to-left shunt at atrial level resulting in hypoxaemia, high haematocrit and hyperviscosity syndrome. The purpose of this study was to assess the results of percutaneous closure of atrial right-to-left shunt in patients with Ebstein's anomaly.
  
  
  RESULTS
  Records of patients treated between January 2002 and June 2010 were reviewed. Their condition before and after shunt closure (clinical data, oxygen saturation and haematocrit) were studied. During this period nine selected patients with Ebstein's anomaly and right-to-left shunt at atrial level were treated. Ages ranged from six to 67 years; seven were male. Mean pulmonary artery pressures were under 25 mmHg in all. Three patients had previous episodes of stroke and three had very high haematocrit, two of whom required therapeutic phlebotomies. Test occlusion of the shunt was performed in all patients with a balloon catheter, revealing an increase in systemic oxygen saturation, with right atrial pressures remaining <18 mmHg in all. Percutaneous closure of atrial shunt was achieved in all. There were no major complications. Arterial oxygen saturations increased in all patients from 85.0 ± 4.5% to 96.7 ± 1.5% (mean ± standard deviation). Medium follow-up was five years. The three patients with very high haematocrit levels had a decrease in its values from 62.9 ± 2.8% to 45.5 ± 3.9% after device occlusion. Both therapeutic phlebotomy programs were discontinued. All patients reported a marked improvement in effort tolerance.
  
  
  CONCLUSIONS
  Percutaneous closure of atrial right-to-left shunt in selected patients with Ebstein's anomaly offers significant improvement, abolishing hypoxaemia and hyperviscosity and preventing paradoxical embolisation.
authors.affiliation: Paediatric Cardiology Department, Hospital de Santa Cruz, Lisbon, Portugal. margaridaoms@gmail.com
authors.forename: Margarida
authors.initials: M
authors.lastname: Silva
authors.forename: Ana
authors.initials: A
authors.lastname: Teixeira
authors.forename: Isabel
authors.initials: I
authors.lastname: Menezes
authors.forename: Graça
authors.initials: G
authors.lastname: Nogueira
authors.forename: Rui
authors.initials: R
authors.lastname: Ferreira
authors.forename: Fernando
authors.initials: F
authors.lastname: Maymone-Martins
authors.forename: Rui
authors.initials: R
authors.lastname: Anjos
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016275:Atrial Function; D001794:Blood Pressure; D001809:Blood Viscosity; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation; D002648:Child; D004437:Ebstein Anomaly / Q000097:blood / Q000150:complications* / Q000503:physiopathology; D019320:Embolism, Paradoxical / Q000209:etiology / Q000628:therapy; D005260:Female; D054092:Foramen Ovale, Patent / Q000097:blood / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D006344:Heart Septal Defects, Atrial / Q000097:blood / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D006400:Hematocrit; D006801:Humans; D000860:Hypoxia / Q000209:etiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011174:Portugal; D011474:Prosthesis Design; D012189:Retrospective Studies; D055989:Septal Occluder Device; D013997:Time Factors; D016896:Treatment Outcome; D014261:Tricuspid Valve / Q000002:abnormalities* / Q000503:physiopathology; D055815:Young Adult
chemical_list: D010100:Oxygen