Peripheral Vascular Disease, Varicose Veins, and Deep Vein Thrombosis

Peripheral Vascular Disease

  • Definition: Reduced perfusion (blood flow) to the extremities (hands, feet).
  • Leads to ischemia, potentially causing necrosis.
  • Similar to atherosclerosis: ischemia → hypoxia/anoxia → tissue death/necrosis.
  • Atherosclerosis-related PVD often results in gangrene (dry or wet).

Etiology and Risk Factors

  • Risk factors (similar to those for atherosclerosis):
    • Smoking
    • Diabetes
    • Hypertension
    • Hyperlipidemia
    • Family history
    • Obesity
    • Sedentary lifestyle
  • Other causes (not in textbook):
    • Coarctation of the aorta: Narrow aorta restricts blood flow. Causes resistance and blood flow issues.
    • Thoracic outlet syndrome: Impingement on brachial plexus nerves and blood vessels (arteries/veins) in the neck/arm area, affecting blood flow.
    • Raynaud disease: Vasospasms in small arteries/arterioles of fingers, triggered by cold or emotional stress.

Clinical Manifestations

  • Intermittent claudication: Painful cramps in legs/feet (commonly), arms/hands (less common).
    • Worse on exertion (exercise) due to increased ischemia.
    • Long-term PVD can cause cramps even at rest.
  • Skin and subcutaneous tissues:
    • Thin skin, especially in lower leg.
    • Cool to the touch, particularly the foot due to decreased blood flow.
    • Continued ischemia leads to ulcers, infections, necrosis, and gangrene (especially in the foot).
  • Pulse:
    • May not be palpable in the lower leg.

Peripheral Arterial Disease

  • Atherosclerotic plaque causes blockages in peripheral arteries, leading to ischemia, pain, pulse issues, claudication.

Peripheral Vein Issues

  • Blockage or defect in the vein.

Varicose Veins

  • Definition: Dilated, enlarged, and tortuous (twisted) superficial veins.

Vein Anatomy and Physiology

  • Veins return blood to the heart from systemic circulation.
  • Skeletal muscle contraction and movement propel blood back to the heart.
  • Valves in veins prevent backflow, especially in legs against gravity.
  • Deep veins rely on skeletal muscle contraction for blood flow.
  • Superficial veins are located just below the skin.

Etiology

  • Venous valve insufficiency: Valves don't close properly, causing backflow and blood pooling (venous stasis).
  • Vessel wall dilation: Valves aren't closing correctly causing bulging in locations along the vein itself. Dilation leads to tortuous shape.

Risk Factors

  • Genetics.
  • Prolonged standing: Standing in one place for long periods.
  • Pregnancy: Puts stress on valves in the veins.
  • Obesity: Puts stress on valves in the veins.

Symptoms and Complications

  • 50% are asymptomatic.
  • Symptoms (if present):
    • Stasis and congestion: Blood pooling.
    • Edema: Due to blood pooling
    • Pain: Due to the congestion.
    • Thrombosis: Because of the blood pooling the propensity to form blood clots is higher.
    • Stasis dermatitis: Inflammation of the skin due to venous stasis
    • Thin skin: Inflammation of the skin due to venous stasis
    • Ulcerations: Difficult to heal, can occur with stasis dermatitis.
  • Chronic venous insufficiency: Can lead to skin discoloration and stasis ulcers.
  • Portal hypertension: Can cause varicose veins in the esophagus or stomach.
  • Scrotum: Varicose veins can occur in the scrotum in males.

Deep Vein Thrombosis (DVT)

  • Definition: Thrombus (clot) formation in the deep veins, independent of inflammation.
  • Deep veins are crucial for returning blood to the heart.
  • Embolus: A clot that breaks off and travels through the bloodstream.
  • Veins → right atrium → pulmonary system: Emboli can lodge in the lungs, causing pulmonary embolism (potentially fatal).

Risk Factors

  • Prolonged immobility: Long periods without movement.
  • Surgery: Increases risk due to immobility and other factors.
  • Trauma: Can damage blood vessels.
  • Hypercoagulability disorders: Conditions that increase the risk of blood clotting.
  • Pregnancy: Increases risk due to hormonal changes and pressure on veins.
  • Cancer: Some cancers increase the risk of blood clotting.
  • Oral contraceptives: Increase the risk due to hormonal changes.
  • Hormone replacement therapy: Increase the risk due to hormonal changes.
  • Obesity: Increases pressure on veins.
  • Smoking: Damages blood vessels.

Clinical Manifestations

  • Commonly in deep veins of the lower leg.
  • Often asymptomatic: Until thromboembolism migrates and causes issues.
  • Leg:
    • Swelling or edema: Accumulation of fluid, edema.
    • Pain or tenderness: Due to the inflammation of the vein.
  • Heart (if DVT migrates to the heart):
    • Chest pain: Due to the blood clot that migrated to the heart.
    • Symptoms similar to myocardial infarction.
  • Lung (pulmonary embolism):
    • Sudden shortness of breath: Difficulty breathing
    • Chest pain: Due to the blood clot in the lungs.
    • Coughing up mucus: Due to the blood clot in the lungs.
    • Dizziness, fatigue: Due to the blood clot in the lungs.
  • Brain (stroke/cerebrovascular accident):
    • Symptoms of cerebrovascular disease/stroke.

Management of DVT

  • Prevention:
    • Movement during long flights: Reduces the risk of blood clots.
    • Post-surgery mobilization: Reduces the risk of blood clots.
    • Compression stockings: Helps maintain blood flow.
    • Heparin: Prevents clotting, often used post-surgery.
  • Treatment:
    • Heparin and warfarin: Anticoagulants to prevent further clotting.

Venous Thrombosis: Virchow's Triad

  • Venous stasis: Slow blood flow.
  • Hypercoagulability: Increased tendency to clot.
  • Vessel wall injury: Damage to the blood vessel lining.
  • These factors contribute to clot formation in deep veins.