Vascular Diseases & Limb Salvage/Amputations

three layers of blood vessels

intima

media

adventitia

to withstand pulsatile flow and higher BP, arterial walls are ____ than veins

thicker

hypertensive vascular disease

-high BP can lead to blood vessel and organ damage

- >139/89 mmhg substantially increased risk of atherosclerosis

HTN accelerates degeneration in large and medium artery walls causing:

-aortic dissection

-cerebrovascular hemorrhage

-plaque formation in vessel walls

arteriosclerosis

hardening of the arteries

-arterial wall thickening and loss of blood vessel elasticity

atherosclerosis

-intimal lesions

-plaques weaken blood vessel walls and can lead to catastrophic thrombosis

formed by cholesterol with a fibrous cap

-mechanical obstruction to blood flow

risk factors for heart disease

• age - progressive disease but clinically manifests between 40-60

• gender - premenopausal women relatively protected

• genetics - family history is most significant independent risk factor for atherosclerosis

consequence of atherosclerotic disease

• large arteries major targets of atherosclerosis

• symptomatic atherosclerotic disease most commonly affects heart, brain and kidneys

• MI, Stroke, aortic aneurysms, PVD are main consequences

• small vessels become occluded reducing distal perfusion

• ruptured plaques can embolize atherosclerotic debris and cause distal vessel occlusion

• destruction of the underlying vessel wall can lead to aneurysm and rupture and/or thrombosis

aneuysms

• localized abnormal dilation of a blood vessel or the heart

  • can be congenital or acquired

true aneurysms

attenuation (thinning) of arterial or heart ventricular wall

false aneurysms

defect in vessel wall leading to hematoma that communicates with intravascular space

abdominal aortic aneurysm (AAA)

• associated with atherosclerosis

• plaque compresses the media leading to compromise of nutrient and waste diffusion

• media degenerates and necroses leading to thinning and weakness of arterial wall

• most common in male smokers

clinical consequences of AAA

• rupture into peritoneal space - fatal hemorrhage

• obstruction of a branch vessel leading to occlusion downstream

• risk of rupture related to size

  • no rupture <4cm in diameter

  • >25% of >5cm

• abdominal aorta dilates normally with age

aortic dissection

• occurs when blood splays apart the planes of the media to form a blood-filled channel in the aortic wall

  • two types

type A aortic dissection

more dangerous from aortic valve to aortic arch and possibly including the great vessels

type B aortic dissection

being distal to subclavian artery

vaculitis

vessel wall inflammation

giant cell (temporal) arteritis (large vessel)

most common form of vasculitis among elderly in the US and Europe

chronic granulomatous inflammation of large to small sized arteries, mainly of the head

ophthalmic arterial involvement can lead to permanent blindness

temporal arteritis pathogenesis

• causes remains unknown

• immune cause supported by granulomatous reaction

• extraordinary predilection to ONE vessel remains unexplained

temporal arteritis clinical features

• vague symptoms (fever, fatigue, weight loss, headache)

• treat IMMEDIATELY with corticosteroids (prednisone) once considered in diagnosis

kawasaki disease (medium vessel vasculitis)

• leading cause of acquired heart disease in children

• acute febrile disease usually in children under age 4

• predilection for coronary arteries that can thrombose and rupture

• cause unknown

• creates autoantibodies to endothelial cells

kawasaki disease clinical features

• AKA mucocutaneous lymph node syndrome
• Conjunctival and oral erythema and erosion
• Edema of the hands and feet, erythema of the palms and soles, a desquamative rash
• Cervical lymph node enlargement
• If untreated 20% develop cardiovascular sequelae
• Coronary arteritis, aneurysm, sudden cardiac death
• With treatment this risk goes down to 4%
• Immunoglobulin and aspirin

wegener granulomatosis (small vessel)

• Necrotizing type of vasculitis
• Acute necrotizing granulomas of the upper respiratory tract (ear, nose, sinuses, throat) or the lower respiratory tract (lung) or both
• Necrotizing or granulomatous vasculitis affecting small to medium-sized vessels (e.g., capillaries, venules, arterioles, and arteries), most prominent in the lungs and upper airways but affecting other sites as well
• Renal disease in the form of focal necrotizing, often crescentic, glomerulonephritis

wegener granulomatosis clinical features

• Males affected more than females
• Average age of onset is 40
• Classic features include persistent pneumonitis with bilateral nodular and cavitary infiltrates (95%), chronic sinusitis (90%), mucosal ulcerations of the nasopharynx (75%), and evidence of renal disease (80%)
• Other features include rashes, muscle pains, articular involvement, mononeuritis or polyneuritis, and fever
• Left untreated, the disease is usually rapidly fatal; 80% of patients die within 1 year
• Treatment with steroids, cyclophosphamide, have turned Wegener granulomatosis into a chronic remitting and relapsing disease

churg-strauss syndrome (small vessel)

• AKA allergic granulomatosis and angiitis
• Very rare – 1 in a million
• Necrotizing vasculitis classically associated with:
• Asthma, allergic rhinitis, lung infiltrates, peripheral hypereosinophilia, and extravascular necrotizing granulomas
• Cutaneous involvement (palpable purpura), gastrointestinal tract bleeding, and renal disease
• Myocardial infiltrates of eosinophils and cytotoxicity caused by them are implicated in the cardiomyopathy seen in Churg-Strauss syndrome; the heart is involved in 60% of patients, and accounts for almost half of the deaths in the syndrome

thromboangiitis obliterans (Buerger Syndrome) (small vessel)

• Distinctive disease that often leads to vascular insufficiency

• Characterized by: segmental, thrombosing, acute and chronic inflammation of medium sized and small arteries

• Usually occurs in HEAVY smokers before age 35

thromboangiitis obliterans (Buerger Syndrome) pathogenesis

the strong relationship to cigarette smoking is thought to be due to direct endothelial cell toxicity by some component of tobacco, or an idiosyncratic immune response to the same agents

thromboangiitis obliterans (Buerger Syndrome) clinical features

• In contrast to the insufficiency caused by atherosclerosis, in Buerger disease there tends to be severe pain, even at rest, related undoubtedly to the neural involvement
• The early manifestations are a superficial nodular phlebitis, cold sensitivity of the Raynaud type in the hands, and pain in the instep of the foot induced by exercise
• Chronic ulcerations of the toes, feet, or fingers may appear, which can be followed in time by frank gangrene
• Abstinence from cigarette smoking in the early stages of the disease often brings dramatic relief from further attacks

raynaud phenomenon

• Exaggerated vasoconstriction of digital arteries and arterioles
• Paroxysmal pallor or cyanosis in the digits of hands or feet
• “Red, white, and blue”
• Proximal to distal
• Vasodilation, vasoconstriction, cyanosis

thrombophlebitis

inflammation of deep leg veins

phlebothrombosis

thrombosis (clot)

deep venous thrombosis (DVT)

• most commonly seen in the legs

• prolonged immobilization leads to decreased blood flow through veins is the leading cause

• diagnosis - exam with new deep lower leg pain and new swelling, occasional erythema

  • doppler ultrasound

• treatment - anticoagulant medications; lovenox → eliquis

superficial venous thrombosis

• not dangerous or life threatening

• occlusion of the superficial small veins usually of lower extremity

• treated with elevation, warm compresses

critical limb ischemia

• most severe form of peripheral vascular disease (PVD)

  • poor circulation of blood flow in extremities form arterial or venous blockage or vessel spasm

  • increased risk of ulceration, numbness

• can and will lead to gangrene

critical limb ischemia evaluation

• ankle brachial index

• doppler ultrasound looking at venous flow

• CT - angiogram

• MR - angiogram

limb salvage

• Push towards limb salvage in trauma, and oncology when possible

• Oncology – limb salvage for bone tumors is possible and technology continues to improve outcomes