Transcatheter patent foramen ovale closure: a treatment for refractory hypoxaemia.

Right-to-left intracardiac shunt through a patent foramen ovale sometimes induces a significant arterial oxygen desaturation. We describe two cases of severe hypoxia due to a patent foramen ovale, treated successfully by transcatheter closure of the intracardiac shunt. One case occurred after implantation of a cardiac assist device, the other patient presented with a platypnoeaorthodeoxia syndrome. Clinical considerations are outlined.