Journal of Vascular and Endovascular Therapy

Description

Effective revascularization of the patient with peripheral artery disease is about more than the procedure. The approach to the patient with symptom-limiting intermittent claudication or limb-threatening ischemia begins with understanding the population at risk and variation in clinical presentation. The urgency of revascularization varies significantly by presentation; from patients with intermittent claudication who should undergo structured exercise rehabilitation before revascularization (if needed) to those with acute limb ischemia, a medical emergency, who require revascularization within hours. Recent years have seen the rapid development of new tools including wires, catheters, drug-eluting technology, specialized balloons, and biomimetic stents. Open surgical bypass remains an important option for those with advanced disease. The strategy and techniques employed vary by clinical presentation, lesion location, and lesion severity. There is limited level 1 evidence to guide practice, but factors that determine technical success and anatomic durability are largely understood and incorporated into decision-making. Following revascularization, medical therapy to reduce adverse limb outcomes and a surveillance plan should be put in place. There are many hurdles to overcome to improve the efficacy of lower extremity revascularization, such as restenosis, calcification, micro vascular disease, silent embolization, and tools for perfusion assessment. This review highlights the current state of revascularization in peripheral artery disease with an eye toward technologies at the cusp, which may significantly impact current practice.

Multisegment Disease

Goals of limb treatment in symptomatic PAD are to relieve pain, maintain ambulatory status, heal wounds, preserve a functional extremity, and improve health-related quality of life. Revascularization plays a central role, particularly in those with more advanced symptoms and presentations. IC classically presents as pain in the calf, thigh, or buttock muscle groups brought on by exertion and relieved by rest. The degree of disability experienced by patients with IC may range considerably and correlates poorly with resting hemodynamic measures of disease. Proximal muscle symptoms generally associate with aorto-iliac (AI or inflow) disease, whereas calf claudication is typically associated with femoro-popliteal (FP) involvement. Multisegment disease is common and often correlates with more advanced symptoms. Smoking cessation, exercise, and guideline-based optimal medical therapy are primary treatments for patients with IC. Upon presentation with a symptomatic lower extremity, patient evaluation should begin with an office-based history and physical examination. The presence of lower extremity symptoms, as described above, may be typical of severe PAD (ischemic ulceration or gangrene for CLTI or muscular pain with walking for claudication) or atypical. The definition of symptomatic PAD remains nebulous as a result of a variety of presentations, rendering most patients as having presentations understood to be uncommon. First, it is common for older aged persons who present for limb symptoms to have a variety of clinical conditions including, but not limited to, joint arthritis, lumbar spine radiculopathy, and venous insufficiency that cause pain at rest and with walking. Thus, aggressive examination of symptoms is needed to find even patients who may not recognize the severity of their limitation. In addition to acquiring a history concerning limb symptoms, a history of other atherosclerotic bed clinical syndromes should be obtained.

Gadolinium

After a careful history, a focused physical examination should be performed to help determine the location of severe atherosclerosis. The primary components of the exam include palpation and auscultation of the carotid arteries, palpation of the brachial, radial, and ulnar pulses, abdominal examination to palpate for an aortic aneurysm and abdominal auscultation to listen for bruits suggestive of limb inflow occlusive disease. Lower extremity pulses should be palpated including the femoral, popliteal, dorsalis pedis, and posterior tibial pulses. Auscultation of the femoral pulses may also identify occlusive disease. The legs should be fully exposed to permit inspection for findings in the skin that may provide context for the presenting complaint. These may include brawny skin changes or atrophie Blanche both indicative of chronic venous hypertension, necrobiosis lipoidica as an indicator of diabetes, and scars that may highlight previous surgery. The foot requires particular examination, with close observation for skin ulceration, cyanosis, poor growth of toenails, toenail fungus, dependent rubor, and gangrene. It is important to remember to look between the toes for lesions that may not be immediately observed. Once the decision to pursue revascularization has been made, the next step is imaging to define the arterial anatomy for revascularization planning. Several modalities are commonly used in this setting. The American Heart Association/ American College of Cardiology Multispecialty Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease and the Joint guidelines of the Society for Vascular Surgery, European Society for Vascular Surgery, and World Federation of Vascular Societies Global vascular guidelines on the management of chronic limb-threatening ischemia recommend the use of duplex ultrasonography, computed tomography angiography, or magnetic resonance angiography for identification of the anatomic location and severity of stenosis before invasive imaging in patients who are candidates for revascularization. Although a complete list of advantages and disadvantages of each modality are beyond the scope of this review, it should be noted that ultrasound is noninvasive and relatively inexpensive, but more subject to operator expertise, limited interrogation of the proximal limb vasculature, and hindered by vascular calcification. Both computed tomography angiography and magnetic resonance angiography are limited in populations with impaired kidney function because of their reliance on contrast agents. Although arterial imaging, in general, is excellent with each modality, computed tomography angiography is limited by calcification and reduced accuracy in distal tibial and pedal vessels while magnetic resonance angiography may be limited by medical devices that preclude their use, a tendency to overestimate stenosis, and venous contamination. If necessary, invasive digital subtraction angiography is widely available, provides a high-resolution anatomic assessment, and may be performed with carbon dioxide or gadolinium to permit evaluation of a wide range of patients.