A novel device for atrial septal defect occlusion (GORE CARDIOFORM)

Abstract

The GORE CARDIOFORM atrial septal defect (ASD) Occluder (GCA) is composed of a platinum-filled nitinol wire frame covered with expanded polytetrafluoroethylene, making it softer and more conformable compared with nitinol mesh devices. After the ASSURED clinical study confirmed the efficacy and safety of the device, it received U.S. Food and Drug Administration approval and a European conformity mark. Our aim was to understand the learning curve implicated in using the GCA for ASD closure in paediatric and adult patients as well as to study the early outcomes. To this end, a review of ASD device closures with GCA in 4 UK centres was conducted between January 2020 and January 2023. Implantation success was the primary outcome; the secondary outcomes were serious adverse events, including new onset arrhythmia. In all, 135 patients were included, and 128 (95%) had successful ASD device closure with GCA. The median patient age was 49 years, the median defect size was 18 mm, and the median device size was 37 mm. The median follow-up time was 6 months (interquartile range 1-14). One device embolisation occurred, and 15 patients (12% of GCA implantations) developed new onset arrhythmia - this was not related to patient age, defect diameter or device oversizing but was positively associated with device size. With growing experience using GCA, the device can be applied to a wide variety of ASD sizes and morphologies. Given the number of successful implantations with an absence of aortic erosion, as well as the ability to perforate through the device should procedures be required in the left atrium, the GCA device is an important addition for interventionists who close atrial septal defects.

Central illustration. Intention-to-treat flowchart.

Successful device implantation was defined as an implanted GORE CARDIOFORM ASD Occluder (GCA) that was not retrieved. Failed intention-to-treat was defined as either an alternative type of device implanted or failed device closure. The device was sized according to manufacturer recommendations (using the diameter of the waist on balloon sizing), oversized (device size larger than manufacturer recommendations) due to deficiency of defect rim(s), or oversized despite adequate defect rim(s).

Figure 1. Graphic representations.

Graphic representation of procedural outcomes (A), patient demographics (B), defect characteristics (C) and device sizing (D).

Figure 2. Incidence of arrhythmias after successful GCA implantation. Fifteen patients (12%) developed a new atrial/supraventricular arrhythmia.

ASD: atrial septal defect; GCA: GORE CARDIOFORM device

Figure 3. Transoesophageal echocardiography and fluoroscopic images of closure of a complex atrial septal defect using a GORE CARDIOFORM device.

A) A 21x18 mm single atrial septal defect (ASD) is shown with left to right atrial low velocity colour flow mapping. It is noted that the primary and secondary septa are separated inferiorly, presenting challenges with encapsulating both septa with the inferior aspect of the disc of the device. The inset figures show balloon sizing stop-flow and deficiency of the ASD to the aorta with a small aortic rim. B) Three-dimensional (3D) left atrial and inset figure right atrial view of the relatively circular ASD. C) A 44 mm GORE CARDIOFORM device has been deployed but the device has failed to capture the inferior septum. This is seen on transoesophageal echocardiography (TOE) (arrow) and also in the inset figure fluoroscopic image which shows that the 2 discs are not separated. D) 3D image of the left atrial disc as in (C), with the arrow tip showing one of the right disc petals in the left atrium. E) Changing to a 48 mm device enabled the inferior aspect of the ASD to be captured with very different and now correct appearances of the device still attached to its delivery catheter and not yet locked both on TOE and also on fluoroscopy (inset image). F) 3D representation of the left atrial disc seen in (E) with none of the right atrial disc seen in the left atrium. G,H) Final appearances of the device following locking in 2 dimensions (G) and 3D (H).