ABSTRACT
Device Unlike other devices, the implant is made of a single spiralshaped nitinol wire with an expanded polytetrafluoroethylene patch attached along its length (Figure 33.1). When the nitinol wire is advanced out of the control catheter, two disks of equal size are developed. The Helex wire frame has three eyelets acting as markers and providing good visibility and positioning of the device under fluoroscopy control (Figure 33.2). There is a circular marker between the two disks of the Helex device and outside the right and left disk, respectively. A locking mechanism connects the centers of the right and the left atrial disk and thereby stabilizes the position of the Helex occluder within the atrial septum. Currently, the device is available in sizes from 15 to 35 mm (disk diameter) in 5 mm increments.
