Interventional closure of defects in the atrial septum using the HELEX septal occluder Neil Wilson
INTRODUCTION The HELEX device is a non-self-centering double disk device of Nitinol and ePTFE (Figure 9.1). The device is designed such that, following introduction across the septum, one disk is constituted on the left atrial side and the other on the right atrial side of the septum. The construction of the device consists of a curtain of ePTFE (GoretexTM, WL Gore & Associates Flagstaff, Arizona, USA) bonded to a single-piece wire frame of Nitinol 0.012 inches. The Nitinol is prepared in the manner of a helical pattern of opposing rotations which on full configuration assumes two parallel disks. The device is delivered through its own composite triaxial 10Fr delivery catheter with a workable length of 75 cm. This obviates the need for a long trans-septal sheath. For patent foramen ovale the delivery system can be monorailed through a hole close to its distal end using a wire placed through a diagnostic catheter positioned in one of the left pulmonary veins.