Peripheral Artery Disease

What Is Peripheral Artery Disease?

Peripheral artery disease (PAD) of the lower limbs is blockage of the arteries in the lower limbs. It may happen suddenly and is usually caused by blood clots. It may also happen over time where the blockage is caused by a build up of atherosclerotic plaques.

The pathology of PAD is similar to coronary artery disease. The prevalence of PAD in high risk Malaysian population is 30-40%. In the past, severe PAD may lead to gangrene in the limbs if left untreated and necessitates some form of amputation. Studies show that 70% of patients who have had an amputation die within 5 years. It is therefore our aim to prevent amputations through early diagnosis and treatment of PAD, with appropriate re-vascularization procedures.

What Are The Risk Factors For Peripheral Artery Disease?

The risk factors of PAD are:

• Diabetes
• Smoking
• Kidney failure
• Hypertension
• Hypercholesterolemia (high cholesterol)

Symptoms

• Sudden severe pain and coldness of the legs / feet (acute critical limb ischaemia)
• Non healing ulcer or slow gangrene and leg/ foot infection
• Claudication pain or pain over the legs or thighs when walking
  

Acute critical limb ischaemia is a vascular or medical emergency. It happens due to the occlusion of arteries by blood clot. If left untreated, the patient’s whole leg or foot will undergo gangrene and may require amputation to preserve life.

Diagnosis

• Ankle Brachial Index (ABI) screening test
• Ultrasound doppler of lower limb arteries
• CT angiogram of lower limb arteries
• Peripheral angiogram of lower limb arteries

The Ankle Brachial Index (ABI) screening test is a measurement of blood pressure of the leg over arm . An ABI of less than 0.9 suggests significant PAD.

The ABI screening test is available at our Health Screening Centre.

Treatment

• Angioplasty of the blockage of the lower limb arteries by an interventional cardiologist
• Wound management by an orthopaedic surgeon
• Antibiotics

The treatment of PAD encompasses a multidisciplinary approach involving a cardiologist or vascular specialist, radiologist, orthopaedic surgeon and support staff, which includes the vascular nursing team and physiotherapists.

Our main aim is to avoid a total amputation of the leg or foot. In some cases, minimal amputation of the toes cannot be avoided especially if a patient leaves the artery blockage untreated for too long, such as when the toes of his or her foot has appeared black.

How Is Peripheral Angiogram Performed?

This minimally invasive procedure is performed by inserting a catheter or tube into the lower limb arteries through the groin or thigh. An angiogram is then performed by injecting contrast media so that the area of stenosis or occlusion can be seen clearly. The procedure is done under local anaesthesia and typically takes about 15-30 minutes.

If there is a significant stenosis or blockage, an angioplasty is then performed with balloon catheters, either with or without vascular stents.

How Is Angioplasty Performed?

Angioplasty is a minimally invasive procedure done under local anaesthesia. A catheter or tube is introduced into the lower limb artery from the thigh, progressing downwards towards the leg. An angiogram is then performed to visualise and demonstrate the areas of blockage. The blockages are then opened up using a balloon with or without stents. We may also utilise balloon catheters with drug coating to prolong the patency of the re-vascularised artery.

In conditions of sudden acute critical limb ischaemia whereby the blockage occurs due to blood clot, the doctor would inject thrombolytic medicine to dissolve the blood clot.

Once a successful angioplasty procedure is performed, the patient would be given blood-thinning medicine, with antibiotics to prevent bacterial infection. Meanwhile, a diabetic patient would need optimal control of blood sugar. The orthopaedic surgeon and vascular nursing team would debride the wound. However, if the wound or gangrene is too extensive, some amount of amputation may be needed. The angioplasty procedure could prevent a major amputation or limit the extent of one if it is unavoidable. The physiotherapy team would then assist in rehabilitation of the patient and fix limb prosthesis where needed.

Overall, the successful treatment outcome of a PAD patient with gangrene or chronic non-healing ulcers relies on the co-operation of a multidisciplinary medical team working together to achieve the best results for the patient.