Peripheral Arterial Disease:Arteriosclerosis & Atherosclerosis.

PST 515 – Physiotherapy in disorders of Blood and Lymph Vessels

Peripheral arterial disease

• Peripheral arterial disease (PAD) is a condition in which there is obstruction to blood flow in the arteries of the limbs particularly the lower limbs.

• The obstruction is caused by plaque deposits that impede blood flow

• Peripheral arterial disease is considered to be a set of chronic or acute syndromes, generally derived from the presence of occlusive arterial disease, which cause inadequate blood flow to the limbs.

• On most occasions, the underlying disease process is arteriosclerotic disease mainly affecting the vascularization to the lower limbs

• Symptoms of PAD include claudication, skin ulcers, cramping, aching, clubbing of the finger or toenails, cold skin, cyanosis, and slow capillary refill.

Peripheral arterial disease

• The reduction in blood flow slows down the clearance of anaerobic metabolites and this causes pain sensation

• If the reduction in blood flow is severe it can lead to limb ischaemia causing pain, ulceration and gangrene

• The most common cause of PAD is atherosclerosis

• Other cases are arteriosclerosis, vasculitis, thromboangiitisobliterans, popliteal entrapment syndrome.

Peripheral arterial disease

• The ischaemia that occur in the lower limb can be classified as functional or critical.

• Functional ischemia occurs when the blood flow is normal at rest but insufficient during exercise, presenting clinically as intermittent claudication.

• Critical ischemia is produced when the reduction in blood flow results in a perfusion deficit at rest and is defined by the presence of pain at rest or trophic lesions in the legs.

Classification of symptoms (Leriche-Fontaine classification)• The symptoms in patients with PAD in the limbs caused by chronic

arterial disease can be stratified according to the classification of Leriche-Fontaine.

• This classification, which groups patients who have progressive arterial failure into 4 stages, has prognostic value and is very useful for treatment indication.

Classification of symptoms

• Grade I - Asymptomatic, Detectable by ankle-arm index

• Grade IIa - Intermittent claudication not limiting the patient’s life style

• Grade IIb - Intermittent claudication limiting for the patient

• Grade III - Pain or paraesthesia at rest

• Grade IV - Established gangrene. Trophic lesions

Arteriosclerosis

• This is a degenerative process where elastic tissue is replaced by fibrous tissue and the tunica media becomes thickened.

• It is a part of the normal aging process

• There is a hardening of the arteries. If this occurs the vessels of the brain, heart and kidneys, it is a major cause of disability or death.

• Co-morbidities include kidney disease, high blood pressure, uremia, stroke, angina pectoris, coronary heart disease and coronary thrombosis.

Pathology

• Degenerative changes begin in the tunica media of medium sized artery with disruption of muscle and elastic tissue

• The changes later spread to the tunica intima and calcium is deposited in the tunica media to replace the degenerative tissues. This result in loss of elasticity thus increasing peripheral resistance and raising blood pressure

Atherosclerosis

• It is most common occlusive arterial disease

• It is characterized by deposit of mass lipid (atheroma) in the inner wall of the vessels

• May coexist with arteriosclerosis

• This characterized by an abnormal mass of lipid materials (atheroma) in the intima layer of an artery

• The majority of patient are aged over 50 and the disease is rarely in people under 30 males are more affected than females.

Atherosclerosis

• Atherosclerosis is a progressive disease of the arteries that results in the development of heart disease and stroke.

• Atherosclerosis results from an initial injury to the artery endothelium caused by mechanical and environmental factors, resulting in an inflammatory response in the vessel wall.

• It is characterised by the disrupted balance and abnormal accumulation of lipids, inflammatory cells, matrix deposits and smooth muscle cell proliferation in the wall of medium- and large-calibre arteries.

Predisposing (Risk) factors

• Diet

• Dyslipidaemia

• Diabetes

• Cigarette smoking

• Hypertension

• Obesity

• Physical inactivity

• alcoholism

Pathology of atherosclerosis

• Lipid materials are deposited on the tunica intima with associated damage to the endothelial lining.

• Fibrin is laid down over the lipid material causing patches of raised areas on the intima. Platelets stick to the exposed collagen fibers, forming a localized clot that restricts arterial blood flow, leading to inadequate tissue perfusion

• Thrombolites are trapped on this areas and this leads to thrombus formation.

• The underlying intima becomes softened resulting in ulcer. This ulceration leads to inflammation. As thrombus formation continues, the lumen of the vessel becomes occluded although there is likelihood of collateral circulation.

Atherosclerosis

Clinical Features

• The clinical features depends on the area of affectation

• If the vertebra artery is involved, it may cause dizziness or impaired vision

• If the iliac, femoral and popliteal arteries are involved, the features are:

• Intermittent claudication – (cramp like pain) which comes on during walking or exercise at the calf pain.

• Rest pain

• Cold limbs

• Sensory changes

• Skin changes

• Loss of pulse

• There may be complications such as aneurysm and rupture of an artery.

Investigations

• Ankle brachial index (0.9 – 1.0- normal, 0.7-0.89 – mild disease, 0.4 – 0.69 –moderate disease, less than 0.4 – severe)

• Palpation and comparison of pulses in the involved and uninvolved upper or lower extremities

• Blood glucose and urine analysis• Skin temperature• Skin integrity and pigmentation• Tests for reactive hyperaemia (rubor of dependence)• Ultrasonography, Doppler measurement of blood flow,• Magnetic resonance angiography• Arteriography

Management

• Medical management: use of analgesic to relieve pain

• Use of anticoagulant

• Dietary advise: low animal fat and cholesterol intake

• Surgical intervention to repair valves in the vessels for smoother blood flow.

• Medical treatment of patients with PAD has 2 objectives. • One, to improve the functional situation of the limb

• Two, to prevent events secondary to the multifocal distribution of the disease.

Physiotherapy management

• Supervised graded exercise programme• Walking• Treadmill exercise• Bicycle ergometry

• Pain management

• Sensory stimulation

• Soft tissue mobilization / massage

• Muscle strengthening exercise

• Joint mobilisations

• Provision of assistive device

Physiotherapy management• Buerger’s exercise: this is a position designed to

encourage development of a collateral circulation in the leg.

• The patient lies supine with the legs supported in the elevation at an angle of 450 to the horizontal until the skin blanches. This position is maintained for 2 minutes

• the patient sits up with the legs dependent until the skin colour is bright red (for about 3 minutes)

• The patient lies with the legs horizontal until the skin colour returns to normal (for 5 mins)

• This pattern is repeated 4 or 5 times three times daily