What is peripheral arterial disease (PAD)?
Peripheral arterial disease occurs when plaque forms in the walls of arteries which can lead to narrowing and eventually complete blockage of blood flow. It can occur in any artery of the body, being most common in the legs. When it occurs in the legs, the narrowing can cause claudication, rest pain, and non-healing wounds/ulcers. Claudication is cramping in an extremity which is usually consistently brought on by activity and is improved with resting.
When the narrowing advances, this can lead to rest pain which is pain without any activity. With continued progression of the disease, the tissues cannot get enough blood which leads to non-healing wounds and tissue loss. Involvement of the arteries to the kidneys can lead to uncontrolled high blood pressure and decreased kidney function. Disease in the blood vessels to the stomach and bowel can lead to pain after eating which can lead to food avoidance and excessive weight loss. Disease in the vessels of the neck can lead to strokes.
How is PAD diagnosed?
Diagnosing PAD starts with obtaining a history of symptoms and risk factors followed by a physical exam. This is followed by a simple non-invasive screening test called an ankle-brachial index (ABI). A blood pressure cuff is applied to the arm and the ankle and an index calculated. This will show if significant disease is present, but will not localize the level.
To localize the level, another exam can be performed where ultrasound is utilized to look at the arteries at various locations along the legs. In some instances, a CAT scan or MRI can be obtained. Finally, the most accurate but invasive study is an arteriogram. In this study, a small catheter is inserted into an artery in the hip and contrast injected into the vessels of interest.
How is PAD treated?
Treatment ranges from simple conservative therapy to more aggressive and invasive surgery. Conservative therapy would include exercise, quitting tobacco, and diet modification. Medical therapy can be used to control other risk factors such as high blood pressure, diabetes, and elevated cholesterol. Minimally invasive treatment options can be performed at the time of the diagnostic arteriogram. These are performed through a small incision in the groin which leads to a quicker recovery time. Most of the procedures can be performed as an outpatient with mild sedation allowing the patient to go home the same day.
Treatment options include angioplasty, atherectomy, and stent placement. Angioplasty consists of temporarily inflating a balloon in the diseased vessel which opens up the narrowed area. The balloon is then deflated and removed. Atherectomy consists of inserting a device that removes the arterial plaque using either a blade, burr, or laser creating a larger lumen in the vessel. A stent is an expandable tube made of wire scaffolding that can be used to hold open the area of narrowing. If less invasive treatment is not successful, the patient can go on to a more invasive surgical treatment where the plaque is removed with an open incision (endarterectomy) or the diseased vessel segment is bypassed with a vein or a synthetic graft.