Below-the-ankle Intervention: Vascular Anatomy and How We Do It

Learning Objectives: To illustrate the below-the-ankle (BTA) vascular anatomy.
To review the available devices and procedural steps in BTA interventions.
To summarize the recent outcome data on BTA interventions in managing patients with chronic limb ischemia.

Background: Critical limb ischemia (CLI) is an increasingly prevalent disease, and is associated with significant morbidity and mortality. The presence of BTA lesions play a major role in the preservation of ankle joint and avoidance of major amputation. Therefore, BTA lesions should be addressed when necessary to preserve limb functionality and to reduce patient morbidity and mortality.

The goal of distal infrapopliteal disease management is to establish in-line arterial flow directly to the distal wound bed. Due to the challenging anatomy, endovascular therapy is preferred over surgical revascularization. Recent data have suggested that BTA interventions carried survival benefits related to the preservation of ankle joints and improved wound healing; therefore, it has become an important adjunct tool for managing complex CLI patients. BTA interventions are technically challenging, and there is a paucity of reports on the techniques and approaches. We aim to illustrate the anatomical and technical aspects of BTA intervention, as well as recent outcome data.

Clinical Findings/Procedure Details: In this educational exhibit, we will A) provide a pictorial review of detailed BTA anatomy, including the pedal arch, dorsalis pedis, plantar arteries and the major tributaries; B) present diagrams as well as angiography images in various obliquities to best demonstrate the said vascular anatomy; C) detail our technical approach to BTA interventions, including the access sheath, access technique/location, common crossing and working wires, common support catheters, balloons (plain and specialty balloons), lithotripsy devices, and atherectomy devices; and D) summarize the most recent literature on BTA outcomes, including the recent Liberty 360 trial.

Conclusion and/or Teaching Points: BTA interventions have become a critical tool in managing complex CLI patients. Practitioners should be familiar with the basic BTA vascular anatomy in order to provide targeted therapy. Knowledge of the available wires/catheters/specialty devices, as well as technical approaches, can better prepare clinicians in managing this complex condition.