Transcatheter device closure of interatrial septal defects in patients with hypoxia

There has been growing interest in transcatheter closure of interatrial septal defects (IASDs) for a variety of indications, but reports are limited in patients with hypoxia from right-to-left shunting.

Between August 2000 and October 2004, 181 patients were referred to our institution for elective closure of a patent foramen ovale (PFO) or atrial septal defect (ASD). Among these patients, 10 (5.5%) underwent closure for hypoxia due to persistent or intermittent right-to-left shunting. Clinical evaluation, including echocardiography with color Doppler and agitated saline, was performed in all patients to determine the degree of right-to-left shunting. Defects were closed with Amplatzer (n = 4) or Cardioseal (n = 6) devices, under transesophageal (TEE) or intracardiac echocardiography (ICE) guidance.

Mean age was 62.7 years (range: 31-88 years) with 70% female. Characteristics for closure included four patients with persistent hypoxia and six with intermittent hypoxia, including two with platypnea-orthodeoxia syndrome. All patients had echocardiography showing moderate (n = 6) or severe (n = 4) shunting. Patients had significant comorbidities, including chronic lung disease requiring supplemental oxygen (n = 5) and congestive heart failure (n = 2). TEE guidance was used in three patients, and ICE was performed in the remainder. Mean closure device diameter was 27 mm. Mean preprocedural arterial oxygen saturation of 86.7% improved to 95.9% immediately after closure, with color Doppler and agitated saline revealing the absence of (n = 5) or mild (n = 5) shunting. In-hospital major complications were limited to one patient with a transient ischemic attack after an initially unsuccessful closure attempt.

Percutaneous closure of IASDs in a heterogeneous group of patients with hypoxia can be safely and effectively performed. The procedure results in immediate arterial saturation improvement and reduced right-to-left shunting.