Transcatheter closure of patent foramen ovale using the Amplatzer septal occluder to prevent recurrence of neurological decompression illness in divers

Objective-Large flap valve patent foramens may cause paradoxical thromboemb olism and neurological decompression illness in divers. The ability of a se lf expanding Nitinol wire mesh device (Amplatzer septal occluder) to produc e complete closure of the patent foramen ovale was assessed. Patients-Seven adults, aged 18-60 years, who had experienced neurological d ecompression illness related to diving. Six appeared to have a normal atria l septum on transthoracic echocardiography, while one was found to have an aneurysm of the interatrial septum. Methods-Right atrial angiography was performed to delineate the morphology of the right to left shunt. The defects were sized bidirectionally with a p recalibrated balloon filled with dilute contrast. The largest balloon diame ter that could be repeatedly passed across the septum was used to select th e occlusion device diameter. Devices were introduced through 7 F long sheat hs. All patients underwent transthoracic contrast echocardiography one mont h after the implant. Results-Device placement was successful in all patients, Device sizes range d from 9-14 mm. The patient with an aneurysm of the interatrial septum had three defects, which were closed with two devices. Right atrial angiography showed complete immediate closure in all patients. Median (range) fluorosc opy time was 13.7 (6-35) minutes, Follow up contrast echocardiography showe d no right to left shunting in six of seven patients and the passage of a f ew bubbles in one patient. All patients have been allowed to return to divi ng. Conclusion-The Amplatzer septal occluder can close the large flap valve pat ent foramen ovale in divers who have experienced neurological decompression illness. Interatrial septal aneurysms with multiple defects may require mo re than one device.