The value of transesophageal echocardiography in transcatheter closure of atrial septal defects in the oval fossa using the Amplatzer septal occluder

BACKGROUND: From January, 1997, as part of an international multicentric trial, we have been closing small-to-moderate atrial septal defects within the oval fossa using the Amplatzer Septal Occluder (ASO, AGA Medical).

METHODS: All patients with defects within the oval fossa deemed potentially suitable for transcatheter closure were investigated by transesophageal echocardiography with the aim of gaining extra information that might alter the decision to use the device to close the defect. Views were obtained in transverse and longitudinal planes, permitting measurements of the diameter of the defect, and its distance from the atrioventricular valves, coronary sinus, and pulmonary veins. Additionally, we sought to identify multiple defects, and to exclude sinus venosus defects.

RESULTS: Of 56 patients with left-to-right shunts, 41 (73.2%) were deemed suitable for closure with the Amplatzer Septal Occluder. All underwent the procedure successfully, with no complications. This includes 5 patients with multiple small defects that were sufficiently close to the main defect to be closed with a single device. Only two of these had been detected on the transthoracic study. In the remaining 15 of 56 patients, transcatheter closure was deemed unsuitable. In 9 patients, this was due to the limitation of the size of the device available during the period of study, this representing a relative contraindication. In the remaining 6 (10.7%), transcatheter closure was not performed because multiple defects were too far apart to be closed with a single device in 3 patients, two patients were noted to have a sinus venosus defect, and another was noted to have anomalous connection of the right upper pulmonary vein to the right atrium. Excluding patients contraindicated due to the size of the defect alone, transesophageal echocardiography provided extra information in one-tenth of our patients, which altered the decision regarding management.

CONCLUSION: Transesophageal echocardiography is indispensable in the evaluation of patients undergoing transcatheter closure of atrial septal defect.