Aetiology: Insufficient tissue perfusion due to atherosclerosis in the aorta and peripheral arteries (Atherosclerotic plaques reduce the arterial lumen → arterial insufficiency distal to the occlusion.)

Risk Factors: same as Atherosclerosis. Smoking, Diabetes mellitus, Arterial HTN , Dyslipidaemia, FHx: cardiovascular events in the first-degree relatives below the age of 55 (male)/65 (female), High homocysteine levels (homocystinuria), Obesity, High fibrinogen levels, Hyperphosphatasemia, Stress, Increased alcohol consumption

Clinical Presentation

• Mild ischemia: Asymptomatic
• Moderate ischemia: Claudication, Walking impairment (e.g. fatigue, cramping or pain in butt, thigh, calf or foot) quickly relieved by rest. Onset more rapid walking uphill. Can occur bilaterally, typically worse in one.
• Critical ischemia
  • Ischaemic rest pain
  • Unremitting pain in the foot, particularly at night
  • Partially relieved by hanging the foot out of the bed
  • May lead to ulceration or gangrene
• Acute limb ischemia (5 P’s)
  • Pulselessness
  • Pain
  • Pallor
  • Paraesthesia
  • Paralysis

Investigation

• ankle brachial index
• doppler USS
• CT angio

Management

• Aggressive modification of CVD risk (SNAP factors and weight loss)
• Graduated walking program
• Statin therapy
• ACEI therapy
• Antiplatelet drugs

For critical/chronic ischemia, as above + vascular reconstruction

Acute limb ischemia -> emergent IV heparin 80units/Kg loading dose -> 18units/hr IV adjusted acc. to APTT