Critical limb ischemia.

Critical limb ischemia (CLI) is the most severe manifestation of peripheral artery disease (PAD). Without timely recognition, appropriate diagnosis, and revascularization, patients with CLI are at risk for amputation or potentially fatal complications. The past decade has seen substantial growth in endovascular CLI therapies and options now exist for treating long-segment lower-extremity arterial occlusive disease, but surgical bypass may yield more durable results. Patients who are younger, more active, and at low risk for surgery may have better outcomes with an operation. Surgical treatment is also indicated for failures of endovascular therapy, which may include early technical failures or later occlusion after placement of stents or other interventions.