Therapeutic Angiogenesis Using Bone Marrow-Derived Mononuclear Cell Implantation for Patients With Critical Limb-Threatening Ischemia Caused by Thromboangiitis Obliterans ― Study Protocol for a Multicenter Prospective Interventional Trial ―

Background:Patients with thromboangiitis obliterans (TAO) can develop critical limb-threatening ischemia (CLTI) and require limb amputation. Smoking cessation and exercise therapy are recommended as standard treatments, and revascularization by bypass surgery or endovascular therapy (EVT) is required for patients with CLTI. However, there are many cases in which revascularization is difficult because of vascular characteristics, and the patency rate after revascularization remains unsatisfactory. Therapeutic angiogenesis using bone marrow-derived mononuclear cell (BM-MNC) implantation is used clinically, with many trials demonstrating long-term efficacy and safety of the technique in patients with CLTI, especially that caused by TAO. To expand the use of BM-MNCs implantation in clinical practice, further evidence is required in patients with CLTI caused by TAO.