Intermediate term follow-up on transcatheter closure of atrial septal defects by Amplatzer septal occluder.

BACKGROUND: Surgical repair of secundum atrial septal defect (ASD) is a safe, widely accepted procedure with negligible mortality. However, it is associated with morbidity, discomfort and a thoracotomy scar. As an alternative to surgery, a variety of devices for transcatheter closure of ASD have been developed.

OBJECTIVES: We report our clinical experience with transcatheter closure of ASD using the Amplatzer Septal Occluder, a new occlusion device with intermediate term follow-up.

PATIENTS & METHOD: Patients having ASD met established two-dimensional echocardiographic criteria for transcatheter closure were selected. ASD size was measured by transesophageal echocardiogram (TEE) and balloon occlusion catheter (stretched diameter). The Amplatzer's size was chosen to be equal to or 1 mm less than the stretched diameter. The device was advanced transvenously into a guiding sheath and deployed under fluoroscopic and TEE guidance. Once its position was optimal, it was released. TEE was undertaken to demonstrate the residual shunt.

RESULTS: There were 26 patients with a mean age of 17.2 +/- 15.9 years old (2 to 60) and a mean weight of 22 +/- 37.5 kg. (10.7 to 62.5). The mean ASD diameter measured by TEE was 18.3 +/- 5.2 mm. and by stretched diameter was 22 +/- 7.5 mm. Four patients who had ASD stretched diameter over 32 mm were excluded because a larger device was not available. Devices were deployed in 22 patients with sizes from 9 to 30 mm (median = 22mm). Immediately after closure a tiny residual shunt was observed at the core of the device in each case. At 24 hours only two patients had a small (< 2 mm) shunt. One patient with fenestrated ASD had a device embolized into the right ventricle with successful removal and surgical closure. Patients were followed-up for a mean duration of 8 +/- 3.5 months (from 3 to 12 months). Complete occlusion was found in 20 out of 21 patients (95%).

CONCLUSION: The Amplatzer Septal Occluder is a new device designed for closure of different sizes of ASD and can be easily and safely deployed. Our experience showed that this device could be used to close an ASD as large as 30 mm. The intermediate term follow-up also demonstrated an excellent closure result. Caution should be undertaken with patients who have a fenestrated atrial septal defect particularly at the septal rim.