Atrial right-to-left shunting causing severe hypoxaemia despite normal right-sided pressures. Report of 11 consecutive cases corrected by percutaneous closure

Eur Heart J. 2000 Mar;21(6):483-9. doi: 10.1053/euhj.1999.1944.


Background: Hypoxaemia resulting from a right-to-left shunt occurs in patients with atrial septal defects and high pulmonary vascular resistance, but it is uncommon without pulmonary hypertension.

Methods: We report on 11 consecutive patients (age: 59-78 years) in whom a patent foramen ovale or a small atrial septal defect with normal right-sided pressures led to significant cyanosis with clinical symptoms. Six of them had associated platypnoea and orthodeoxia. The diagnosis was confirmed by contrast transoesophageal echocardiography showing an atrial right-to-left shunt.

Results: All but one were successfully treated by percutaneous closure of the inter-atrial defect. In one patient, delivery of the occluder failed due to kinking of the introducing sheath. Four complications were observed following the procedure: two supraventricular arrhythmias and a cerebrovascular accident, all resolved without sequelae; one patient died from a septic shock unrelated to the procedure. During follow-up (up to 30 months), no patient experienced any episode of desaturation due to inter-atrial shunting.

Conclusion: Cyanosis without pulmonary arterial hypertension in the adult should prompt the performance of contrast transoesophageal echocardiography to identify a possible atrial right-to-left shunt. Percutaneous closure of the defect allows efficient and rapid correction of the hypoxaemia and avoids the need for surgical closure.

MeSH terms

  • Aged
  • Angioplasty, Balloon, Coronary* / adverse effects
  • Coronary Angiography
  • Echocardiography, Transesophageal
  • Female
  • Heart Septal Defects, Atrial / complications
  • Heart Septal Defects, Atrial / diagnostic imaging
  • Heart Septal Defects, Atrial / therapy*
  • Humans
  • Hypoxia / etiology*
  • Male
  • Middle Aged
  • Treatment Outcome