Features of treatment of critical ischemia of the lower extremities: direct and indirect methods of revascularization

The issues of treatment of critical lower limb ischemia (KINK), an acute syndrome complex representing a severe outcome of chronic arterial insufficiency due to obliterating vascular diseases (OSD), are considered. It is the appearance of KING, which occurs in every 10–12 patients with OS, that causes them to have a high risk of amputations and adverse outcomes. A pathogenetically based approach in the treatment of CINK is restorative and reconstructive interventions that promote direct vascularization of the arterial bed. In cases of infra-lingual arterial lesion, synthetic prostheses used in other proximal types of reconstructions have very limited use. The use of autovenous conduits for femoral-tibial reconstructions, which is considered the «gold standard», cannot be performed due to a number of technical conditions in almost every third patient with KINK.In such cases, vascular freshly prepared or cryopreserved allografts or freeze-dried xenografts are of particular importance. However, after their use, there is a high risk of aneurysmal degeneration of shunts, hyperacute or chronic rejection, diffuse fibrosis of the wall with lumen stenosis. Indirect vascularization methods used in KINK, as well as various X-ray vascular interventions, including percutaneous transluminal balloon angioplasty followed by endostentation or endovascular rotational and laser atherectomy, can be used only in a limited number of patients with distal arterial blood flow damage. Alternative treatment options in these cases are drugs aimed at improving microcirculation; genetically engineered compositions containing individual neovasculogenesis activation factors or stem cells providing cellular tissue revascularization and paracrine effects.