Transvenous closure of secundum atrial septal defects: preliminary results with a new self-expanding nitinol prosthesis in a swine model

Percutaneous closure of secundum atrial septal defect with a new self centering device ("angel wings")

OBJECTIVE

To investigate the safety, efficacy, and clinical application of a new self centering device ("angel wings") for closure of secundum atrial septal defects (ASD II) and persistent foramen ovale in all age groups.

DESIGN

Multicentre, prospective, nonrandomised study.

PATIENTS

INCLUSION CRITERIA

defects with an occlusive diameter of < or = 20 mm and a surrounding rim of > 4 mm; body weight > 10 kg; and an indication for surgical closure of secundum atrial septal defect. Additionally, there were compassionate indications for closure in patients with persistent foramen ovale.

INTERVENTIONS

Defects were closed by a transcatheter device consisting of two square frames made of superelastic nitinol wire. The frames are covered by elastic polyester fabric, which is sewn together at a central circle. All procedures, except for three interventions that were carried out under sedation, were performed under general anaesthesia using transoesophageal echocardiography and fluoroscopy to monitor intervention.

RESULTS

Closure was attempted in 75 (71%) of 105 patients. An ASD II was present in 35 children and 15 adults. A persistent foramen ovale was present in 25 adults with suspected paradoxical embolism. Transcatheter closure was unsuccessful in three children and crossover to surgery was required. Residual shunts were found in 20 patients (27%) immediately after the procedure. A transient atrioventricular third degree block occurred in three patients (4%) and the right atrial disk was not fully deployed in three. A minor shunt (< 3 mm) was present in only three (4%) of 72 patients during follow up of 1-17 months. Blood clots on the right atrial disks in two patients (one required lysis) were seen during follow up transoesophageal echocardiography. Serious complications demanding surgical removal of the device occurred in three patients. One patient had haemopericardial tamponade because of an aortic lesion. Left atrial thrombus formation due to an unfolded right atrial disk was found in a second patient and dislodgement of the left atrial disk resulted in a large residual shunt in a third.

CONCLUSIONS

Percutaneous closure of a central ASD with a diameter < or = 20 mm in paediatric and adult patients is feasible and effective with this new device. It is a promising alternative to surgical closure. Modifications of the design, however, seem to be mandatory as 4% of patients developed serious complications.

Transcatheter closure of atrial septal defects within the oval fossa: medium-term results in children using the 'ASDOS'-technique

OBJECTIVES

The purpose of this study was to evaluate the safety and efficacy of the ASDOS-technique (Sulzer-Osypka GmbH, Germany) for transcatheter closure of atrial septal defects within the oval fossa.

BACKGROUND

Although several attempts have been made to occlude defects within the oval fossa by transcatheter techniques, none of these has gained general acceptance.

METHODS

Patients with a defect in the oval fossa measuring equal to or less than 20 mm diameter, with a residual septal rim of 5 mm or greater, body weight greater than 10 kg, with clinical indications for surgical closure were considered for transcatheter closure. Follow-up investigations were performed at discharge, after 1, 3, 6 and 9 months, as well as after 1 and 2 years.

RESULTS

Of 78 patients considered for closure, a device was inserted in 41 patients (53%), with success being achieved in 40 patients (98%). The ages ranged from 1.1 to 15 years (7.8 +/- 1.92 years), the 'stretched' diameter of the defect from 10 to 20 mm (14.7 +/- 2.60 mm), and the diameters of the inserted devices from 25 to 45 mm (33.2 +/- 5.43 mm). Transient impairment of atrioventricular conduction occured in 4 patients. During the follow-up of 23.0 +/- 5.6 months elective surgical closure of a residual shunt was performed 26 months after insertion of the device in one patient. None of the other patients required surgery, hospitalisation or medical treatment, and none is requiring further treatment of the defect within the oval fossa. Fracture of one arm of the device occurred in 4 patients, but the fractured arms are in an unchanged and stable position after a period of at least 19 months.

CONCLUSIONS

Our medium-term data show that transcatheter closure in children of defects within the oval fossa can be performed with a high efficacy and safety using the ASDOS-device.

Impact of dynamic 3D transoesophageal echocardiography in the assessment of atrial septal defects and occlusion by the double-umbrella device (CardioSEAL)

Occlusion of the atrial septal defects in the oval fossa by interventional catheterization has progressed, but still has limitations. Three-dimensional (3D) echocardiography can provide unique views unavailable by cross-sectional imaging. The objective of this study was to define the clinical application of 3D echocardiography in the assessment and monitoring of transcatheter occlusion of atrial septal defects. Three-dimensional echocardiography was attempted prior to occlusion of atrial septal defects in 41 patients (median age 8.6 years). Serial cross-sectional images were acquired by multiplane transoesophageal echocardiography and displayed by means of computer reconstruction. Dynamic 3D echocardiographic images of defects in the oval fossa were obtained in 40 of 41 patients (98%). Volume-rendering demonstrated the anterosuperior rim in 36 (90%) and the inferoposterior rim in 24 (60%), but failed to reveal small additional fenestrations in six. Sizes measured by 3D echocardiography were significantly larger than those provided by cross-sectional transoesophageal echocardiography (p=0.007), but differed little from those obtained with balloon sizing (p=0.6). After occlusion, 3D echocardiography showed positions of all arms of the device in 20 of 24 cases. Location of any protruding arms, or residual defects, were also clearly revealed. Three-dimensional images obtained in 12 patients during deployment of the double-umbrella device were useful in monitoring its position (single-frame) and for explaining the mechanism of protrusion. Current 3D echocardiography provides clinically relevant information for selection of patients for closure of atrial septal defects by interventional catheterization and when monitoring during implantation. Information obtained by this technique can clarify the mechanism of deployment of the device and closure of the defect, therefore influencing outcomes.

Early clinical experience with use of the 'Amplatzer Septal Occluder' device for atrial septal defect

Device closure of oval fossa atrial septal defects with the Amplatzer Septal Occluder was performed in 26 patients ranging in age from 0.89 to 60.44 years. In eight additional patients no device implant was performed because of the presence of multiple defects or because the defect was of a size unsuitable for closure with the devices currently available. The stretched diameter of the defects that were closed ranged from 4 to 23 mm (mean 14+/-5.4 mm) and device sizes ranged from 4 to 24 mm. Two devices were unstable, of which one embolized to the right atrium after release. Both devices were retrieved at the same procedure. One of these patients subsequently underwent a successful device closure of his defect using a larger (24-mm) device. Three patients had multiple defects, which were successfully closed with a single device. At 1-month follow-up 23/26 (88%) and at 3-month follow-up 22/24 (92%) patients had complete closure of their defects, while two had residual shunts. One further patient who had complete closure of his defect at 1-month post-implant had his device removed and his atrial septal defect patched surgically 8 weeks after device closure. This was done as a result of the development of a vegetation affecting the device after an episode of septicaemia, which was not related to the cardiac problems. There was no procedure-related morbidity or mortality and all patients remain well at the present time.

Occlusion of Fontan fenestrations using the Amplatzer septal occluder

OBJECTIVE

To evaluate the efficacy and safety of the Amplatzer septal occluder device for occlusion of Fontan fenestrations.

SUBJECTS

Five children aged 5-10 years who had undergone a fenestrated Fontan operation.

SETTING

Tertiary paediatric cardiology centre.

METHODS

Each patient had right and left heart catheterisation to assess haemodynamic suitability for fenestration closure. Sizing of the defect was achieved with a balloon wedge catheter and transoesphageal echocardiography. Transcatheter occlusion of the fenestration was accomplished using a 4 mm device in three patients, and 5 mm or 9 mm devices in the other two patients. Residual shunting following occlusion was assessed using angiography and echocardiography.

RESULTS

100% occlusion rate of the fenestration was achieved in all patients. No complications or device failures were seen during the three month follow up period.

CONCLUSION

The Amplatzer septal occluder device is safe, and effectively occludes the Fontan fenestration.

Closure of atrial septal defects with the Amplatzer occlusion device: preliminary results

OBJECTIVES

This study reports our clinical experience with transcatheter closure of secundum atrial septal defects (ASDs) in children, using the Amplatzer, a new occlusion device.

BACKGROUND

None of the devices previously used for transcatheter closure of interatrial communications has gained wide acceptance.

METHODS

We examined the efficacy and safety of the Amplatzer, a new self-centering septal occluder that consists of two round disks made of Nitinol wire mesh and linked together by a short connecting waist. Sixteen patients with secundum ASD met established two- and three-dimensional echocardiographic and cardiac catheterization criteria for transcatheter closure. 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 7F long guiding sheath and deployed under fluoroscopic and ultrasound guidance. Once its position was optimal, it was released.

RESULTS

The mean ASD diameter by transesophageal echocardiography was 14.1+/-2.3 mm and was significantly smaller (p < 0.001) than the stretched diameter of the ASD (16.8+/-2.4 mm). The mean device diameter was 16.6+/-2.3 mm. No complications were observed. After deployment of the prosthesis, there was no residual shunt in 13 (81.3%) of 16 patients. In three patients there was trivial residual shunt immediately after the procedure that had disappeared in two of them at the 3-month follow-up.

CONCLUSIONS

The Amplatzer is an efficient prosthesis that can be safely applied in children with secundum ASD. However, a study including a large number of patients and a longer follow-up period are required before this technique can be widely used.

Transcatheter closure of secundum atrial septal defects using the new self-centering amplatzer septal occluder: initial human experience

Transcatheter closure of secundum atrial septal defect (ASD) using clamshell or buttoned devices is accompanied by a high incidence of residual shunt. Recently, a new self-centering device, the Amplatzer septal occluder (ASO), has been evaluated in an animal model with very good results. Therefore, our purpose is to report on our initial clinical experience with this device. Thirty patients underwent an attempt at catheter closure of their ASDs at a median age of 6.1 yr (range, 2.9-62.4 yr) and median weight of 22 kg (range, 13-69 kg) using the ASO. The median ASD diameter measured by transesophageal echocardiography (TEE) was 12.5 mm (range, 5-21 mm), and the median ASD balloon stretched diameter was 14 mm (range, 7-19 mm). All patients had right atrial and ventricular volume overload with a mean +/- SD Qp/Qs of 2.3 +/- 0.6. A 7F catheter was used for delivery of the device in all patients. The device was placed correctly in all patients. There was immediate and complete closure (C) in 17/30 patients, 10 patients had trivial residual shunt (TS), and 3 had moderate residual shunt (MS). The median fluoroscopy time was 15 min (range, 8-35 min), and the median total procedure time was 92.5 min (range, 40-135 min). There was no episode of device embolization or any other complication. Follow-up was performed using transthoracic echocardiography (TTE) 1 day, 1 mo, 3 mo, and yearly thereafter. At 1 day, there was C of the ASD in 24/30 patients, 3 had TS, 1 had small shunt (SS), and 2 had MS. At a median follow-up interval of 6 mo, there have been no episodes of endocarditis, thromboembolism, or wire fracture. We conclude that the use of the new ASO is safe and effective in complete closure of secundum ASDs up to a diameter of 21 mm in the majority of patients. Further clinical trials are underway.