Histological Analysis of a New Route after Subintimal Crural Angioplasty.

Background: Subintimal angioplasty is an alternative approach in treating critical limb ischemia with crural artery disease. However, route or location of the newly created channel is not understood.

Case Presentation: A 68-year-old man was referred to our hospital with ischemic gangrene of the right big toe. We performed endovascular treatment because he was a poor candidate for bypass surgery. The posterior tibial artery was treated using subintimal angioplasty, although it resulted in early occlusion. We decided that he was not able to receive any further limb salvage treatment and performed amputation below the knee 7 days after treatment. The specimen from the origin of posterior tibial artery to plantar artery bifurcation was resected and the formalin-fixed vessel was cut into 39 segments. Histological analysis showed that the newly formed lumen was comparatively well dilated and created in the media by tearing internal elastic lamina in almost the whole of its length. The severely poor runoff vessels below the ankle were thought to be a main cause of early occlusion.

Conclusions: The newly formed lumen by subintimal crural angioplasty could be well dilated and created in the media.