Endovascular treatment techniques
If a wire cannot be passed through the lumen of a vessel because of chronic total occlusion, what techniques may be used to allow for endovascular treatment?
Subintimal recanalization may be performed. This is a technique that uses a catheter and hydrophilic guidewire to traverse the intima of the vessel adjacent to the site of occlusion and then tunnel through the subintimal space within the vessel wall. At the other side of the occluded segment, the catheter is used to redirect the wire back into the true lumen of the vessel. Angioplasty and stenting can then be performed, allowing the vessel lumen proximal and distal to the occlusion to be bridged through a newly created lumen in the subintimal space. The most difficult step of subintimal recanalization is re-entry into the vessel lumen from the subintimal space. Several crossing devices have been introduced to facilitate this step.