BV

• Vascular disease


  • Two principal mechanisms:
  • Narrowing or complete obstruction of vessel lumina
  • Weakening of vessel walls – dilation and/or rupture
• Congenital anomalies


  • Berry aneurysms
  • Arteriovenous fistula
  • Fibromuscular dysplasia
• Berry aneurysms


  Thin-walled arterial outpouchings in cerebral vessels; fatal intracerebral hemorrhage
• Arteriovenous fistula


  Abnormal connections between arteries and veins without an intervening capillary bed
• Fibromuscular dysplasia


  Focal irregular thickening of the walls of medium and large-sized muscular arteries due to combination of medial and intimal hyperplasia and fibrosis
• Blood pressure regulation


  Function of cardiac output and peripheral vascular resistance
• Hypotension


  Low blood pressure results in inadequate organ perfusion, organ dysfunction and tissue death
• Hypertension


  High blood pressure causes vessel and end-organ damage; one risk factors for atherosclerosis
• Hypertensive vascular disease


  • Risk of Atherosclerosis: > 140 mmHg / >90 mmHg
  • 90% of cases is Idiopathic or Essential HTN
  • Secondary HTN: due to primary renal disease, artery narrowing, neurologic or adrenal disorders
• Mechanism of essential hypertension

  • Reduced renal sodium excretion – key pathogenic feature
  • Decreased Na excretion = Increased fluid volume = Increased cardiac output = Increased blood pressure
  • Increased vascular resistance from vasoconstriction or structural changes in vessel walls
  • Genetic factors
  • Environmental factors
• Vascular wall response to injury

  Injury to vessel wall – Endothelial cells – fundamental basis for vascular disorders
• Arteriosclerosis


  • "Hardening of the arteries"
  • Arterial wall thickening and loss of elasticity
• Types of arteriosclerosis


  • Atherosclerosis - 99%
  • Monckeberg medical calcific sclerosis – 1%
  • Arteriolosclerosis: involves small arteries and arterioles, not strictly part of atherosclerosis, but more related to HTN and DM
  • Hyaline arteriolosclerosis: benign HTN; homogenous, pink hyaline thickening of arteriolar wall, with loss of structural detail and luminal narrowing
  • Hyperplastic arteriolosclerosis: severe HTN; onion skin concentric, laminated thickening of arteriolar walls and luminal narrowing
• Atherosclerosis


  Intimal lesions called atheroma (atherosclerotic plaques) that impinge on the vascular lumen and can rupture to cause sudden occlusion
• Risk factors for atherosclerosis

  • Nonmodifiable: Genetic abnormalities, Family history, Increasing age, Male gender
  • Modifiable: Hyperlipidemia, Hypertension, Cigarette smoking, Diabetes, Inflammation, Endothelial cell injury
• Atherosclerosis development


  1. Accumulation of lipoproteins in vessel wall

  2. Platelet adhesion

  3. Monocyte adhesion to the endothelium

  4. Intima thickening

  5. Differentiation into macrophages and foam cells

  6. Lipid accumulation within macrophages

  7. Smooth Muscle Cells recruitment

  8. Fibrosis -> Calcification -> Aneurysm ->Thrombosis
• Morphologic changes in atherosclerosis

  • Fatty Streaks: minute yellow, flat macules composed of lipid-filled foamy macrophages
  • Atherosclerotic Plaque: white to yellow raised lesions; intimal thickening and lipid accumulation
• Aneurysms


  Congenital or acquired dilations of blood vessels or the heart
• Consequences of aneurysms


  • Obstruction
  • Embolism
  • Impingement on adjacent structures
  • Abdominal Mass
• Predisposing conditions for aneurysms

  • Atherosclerosis – abdominal aortic aneurysms
  • Hypertension – ascending aortic aneurysms
• True aneurysms


  Involve all three layers of the artery (intima, media and adventitia) or the attenuated wall of the heart
• False aneurysms


  Wall defect leads to formation of an extravascular hematoma that communicates with intravascular space
• Abdominal aortic aneurysm


  • Most commonly in the abdominal aorta and common iliac arteries
  • M > F; smokers
  • Inflammatory AAA: lymphoplasmacytic inflammation with may macrophages and giant cells
  • Mycotic AAA: circulating microorganisms seed the aneurysm wall or the associated thrombus
• Thoracic aortic aneurysm


  • Associated with hypertension, bicuspid aortic valves and Marfan syndrome
  • Manifestations: respiratory and feeding difficulties, cough, pain, cardiac disease, aortic rupture
• Aortic dissection


  • Blood splays apart the laminar planes of the media to form a blood-filled channel within the aortic wall
  • Risk groups: 40-60 years of age with HTN / younger patients with connective tissues abnormalities affecting aorta
  • Classification: Proximal, Distal
• Vasculitis


  • Vessel wall inflammation
  • Two most common pathogenic mechanisms: immune-mediated inflammation and direct vascular invasion by infectious pathogens
• Giant cell arteritis "Temporal arteritis"


  • Mainly arteries of the head, temporal arteries
  • Blindness – most feared sequelae
  • Granulomatous wall inflammation
  • Marked ESR elevation known as "polymyalgia rheumatica"
  • Anti-neutrophil antibody (+)
• Takayasu arteritis


  • Involves aortic arch and other heavily elastic arteries
  • Medium and large sized arteries
  • Females; <40 y/o
  • "Pulseless" disease
  • Necrosis
• Polyarteritis nodosa


  • Any medium or small artery; often renal and visceral arteries
  • Infarcts, aneurysms, ischemia
  • Classical autoimmune disease
  • Segmental, transmural, necrotizing inflammation
  • Anti-neutrophil antibodies
  • One of the classical systemic autoimmune diseases (SLE, RA, SS)
• Kawasaki disease


  • Children; <4 years old
  • Large to medium sized vessels
  • Leading cause of ACQUIRED heart disease in children
  • Manifestation: red tongue, adenopathy
  • Anti-endothelial cells antibodies
• Microscopic polyangiitis


  • Hypersensitivity vasculitis or Leukocytoclastic vasculitis
  • Necrotizing vasculitis
  • Capillaries, small arterioles and venules
  • Seen in Henoch-Schonlein purpura
  • Major feature: hemoptysis, hematuria, proteinuria, abdominal pain or bleeding, muscle pain or weakness and palpable purpura
• Granulomatosis with polyangiitis


  • Wegener granulomatosis
  • Middle aged-man
  • Presentation: Bilateral pneumonitis with nodules and cavitary lesions
  • TRIAD: Necrotizing granulomas, Granulomatous vasculitis, Focal necrotizing
• Churg-Strauss syndrome


  • Allergic granulomatosis and angiitis
  • Small vessel necrotizing
  • Associated with asthma, allergic rhinitis, lung infiltrates, eosinophilia, granuloma
• Thromboangiitis obliterans (Buerger disease)


  • Segmental, thrombosing
  • Acute and chronic inflammation
  • Medium and small sized arteries
  • Tibial and radial arteries
  • Early manifestation: cold induced Raynaud phenomenon
• Infectious vasculitis


  • Localized may be caused by direct invasion of arteries
  • Aspergillus and Mucor spp.
  • Can cause thrombosis and infarction
• Raynaud phenomenon


  • Vasoconstrictive of arteries and arterioles in the extremities, fingers and toes
  • White – blue - red
  • Primary: cold or emotions
  • Secondary: SLE, Scleroderma, Buerger disease
• Varicose veins of extremities

  • Abnormally dilated tortuous veins produced by chronically increased intraluminal pressures and weakened vessel wall support
  • Superficial veins of upper and lower leg
• Thrombophlebitis / Phlebothrombosis


  • Deep leg vein 90%
  • DVT – prolong immobilization = venous stasis
  • Sequelae: Pulmonary embolism
  • Edema, cyanosis, heat, pain, tenderness
• SVC syndrome


  • From bronchogenic CA or mediastinal lymphoma
  • "Dusky cyanosis" of head, neck and arms
• IVC syndrome


  • Secondary to neoplasms, ascending thrombosis, AAA
  • Bilateral leg edema
  • Massive proteinuria if renal veins involved