By Dr. Pradeep Mulley

Peripheral artery disease is a common circulatory problem in which narrowed arteries reduce blood flow to the limbs. The legs don't receive enough blood flow to keep up with demand of day to day walking. This causes symptoms, most notably leg pain when walking called claudication which disappears after a few minutes of rest but again pain starts when person starts walking.

What causes PAD?

Atherosclerosis - a condition where fatty deposits (plaques) build up in the artery walls, thereby narrowing the lumen and reducing blood flow. Less commonly, the cause of peripheral artery disease may be blood vessel inflammation, injury to the limb, unusual anatomy of ligaments or muscles pressing on the artery, or radiation exposure. Other factor that raises the risk of PAD include -

· Smoking · Diabetes · Obesity (a body mass index over 30) · High blood pressure · High cholesterol · A family history of peripheral artery disease, heart disease or stroke · High levels of homocysteine, a protein component that helps build and maintain tissue.

People who smoke or have diabetes have the greatest risk of developing peripheral artery disease.

What are the associated complications?

·  Critical limb ischemia - This condition begin as open sores that don't heal, an injury, or an infection of the foot or leg that  progress and  cause tissue death (gangrene), sometimes requiring amputation of the affected limb.

· Stroke and heart attack - The atherosclerosis that causes the signs and symptoms of peripheral artery disease can also build up in arteries supplying blood to the heart and brain.

What are the symptoms?

· Claudication - Painful cramping in hip, thigh or calf muscles after certain activities, such as walking or climbing stairs.

· Leg numbness or weakness, Sores on toes, feet or legs that won't heal

· Coldness in  lower leg or foot, especially when compared with the other side

· A change in the color of  legs

· Hair loss or slower hair growth on feet and legs

· Slower growth of  toenails and Shiny skin on  legs

· No pulse or a weak pulse in  legs or feet

· Erectile dysfunction in men

If peripheral artery disease progresses, pain may occur even at rest or when lying down (ischemic rest pain). It may be intense enough to disrupt the sleep.

Early diagnosis is the key to treatment

Physical exam – the doctor examines for a weak or absent pulse below a narrowed area of your artery, whooshing sounds (bruits) over your arteries that can be heard with a stethoscope, evidence of poor wound healing in the area where your blood flow is restricted, and decreased blood pressure in your affected limb. The following tests may be done to intervene the condition -

· Ankle-brachial index (ABI) - It compares the blood pressure in your ankle with the blood pressure in your arm.

· Ultrasound - Doppler ultrasound evaluates the blood flow through the blood vessels and identifies blocked or narrowed arteries.

· Angiography -  By injecting a dye (contrast material) into the blood vessels, the doctor can view blood flow through the arteries as it happens, using imaging techniques, such as X-ray imaging or magnetic resonance angiography (MRA) or computerized tomography angiography (CTA).

Catheter angiography is a more invasive procedure that involves guiding a catheter through an artery in groin to the affected area and injecting the dye. Although minimally invasive, this type of angiography gives best visualization and allows for simultaneous diagnosis and treatment — finding the narrowed area of a blood vessel and then widening it with a dilating procedure or administering medication to improve blood flow.

How is it treated?

· Medication – medicines are provided to prevent blood clot and improve the blood flow. With the use of vasodilators, the aim is to reduce the blood pressure (under 130/80 mm Hg), lower cholesterol levels (<100 mg/dL) and control pain and other symptoms.

· Thrombolytic Therapy – In case the blood clot is blocking an artery the doctor may inject a clot dissolving drug into the affected artery to break it up.

· Angioplasty – this method is most commonly performed in cases of short segment block. In this procedure, a small (catheter) is threaded through a blood vessel to the affected artery where, a small balloon on the tip of the catheter is inflated to reopen the artery and flatten the blockage into the artery wall, while at the same time stretching the artery open to increase blood flow. Then a stent is inserted in the artery to help keep it open.

· Bypass surgery – This is done in case of long segment of blocked or narrowed artery. A graft bypass is created using a vessel from another part of the body or a blood vessel made of synthetic fabric. 

* Dr. Pradeep Mulley is the Head Interventional Radiologist at Fortis Hospital, Vasant Kunj