• Large Vessel Vasculitis
• Granulomatous vasculitis that classically involved branches of the carotid artery (superficial temporal and Opthalmic arteries)
• MC form of vasculitis in older adults (>50yrs)
• F>M 
• Headache due to temporal artery involvement
• Visual disturbances- ipsilateral blindness due to opthalmic artery involvement
• Jaw claudication
• FLu like symptoms with joint and muscle pain (polymyalgia rheumatica)
• ESR is elevated
• Normal CK
• Biopsy reveals inflammed vessel wall with giant cells and intima fibrosis
• Lesions are segmental
• Diagnosis requires biopsy of long segment of vessels and negative biopsy does not exclude the disease
• Treatment is corticosteriods
• High risk of ipsilateral blindness without treatment

• Large vessel arteritis
• Granulomatous vasculitis that classically involves the aortic arch at branch points
• Classicall young asian female but in general adults < 50 yrs
• Visual and neurological symptoms are present
• At risk for visual defects and stroke
• Weak or absent puls in the upper extremity resulting in a discrepancy in BP between arms > 10mmhg
• "pulseless disease"
• ESR is elevated
• Treatment is corticosteroids  

• Medium vessel vasculitis
• Necrotizing vasculitis involving multiple organs
• LUNGS ARE SPARED
• Classically presents in young adults as:
• Hypertension: renal artery involvement
• Abdominal pain with melena: Mesenteric artery involvement
• Neurologic Disturbances
• Skin Lesions
• Associated with serum HBsAg 
• Early lesions consists of transmural inflammation with fibrinoid necrosis that eventually heals with fibrosis
• String of Pearls appearance on imaging

• Medium vessel vasculitis
• Classically affects Asian children: Boys > girls
• Presents with nonspecific signs including fever, conjunctivitis, erythematous rash of the palms and soles and enlarged cervical lyph nodes
• Coronary artery involvement is common and leads to an increased risk of:
• Coronary artery involvement with MI
• Aneurysm with rupture
• Treatment is aspirin and IV immunoglobulin
• Disease is usually self-limited  

• Medium vessel vasculitis
• M> F, 25-50 yrs
• Necrotizing vasculitis involving digits
• Presents with ulceration, gangrene, and autoamputation of fingers and toes
• Raynaud phenomenon is often present
• Resting pain on forefoot is characterisitic
• Highly assocaited with heavy smoking, treatment is smoking cessation  

• Small vessel vasculitis
• Necrotizing granulomatous vasculitis involving nasopharynx, lungs, and kidneys
• Classic presentation is middle aged man with sinusitis or nasopharyngeal ulceration, hemoptysis with bilateral nodular lung infiltrates and hematuria due to rapidly progressive glomerulonephritis  
• Serum c-ANCA levels correlate with disease activity
• Biopsy reveals large necrotizing granulomas with adjacent necrotizing vasculitis
• Treatment is cyclophosphamide and steroids
• Relapses are common

• Small Vessel vasculitis
• Necrtoizing vasculitis involving multiple organs: lungs, kidney, skin, brain, GI, post capillary venules, and glomerular capillaries
• Presentation is similar to Wegener granulomatosis but nasopharyngeal involvement and granulomas are ABSENT
• Palpable purpura and glomerulonephritis are often present
• Treatment is corticosteroids and cyclophosphamide
• Relapses are common
• Precipitated by:
• Drugs: Penicillin
• Infections: Streptococci
• Immune disorders: SLE  

• Small vessel vasculitis
• Necrotizing granulomatous inflammation with eosinophils involving multiple organs especially lungs and heart
• Asthma and peripheral eosinophilia are often present  
• Serum p-ANCA levels correlate with disease activity

• Small vessel vasculitis
• Vasculitis due to IgA immune complex deposition
• MC vasculitis in childrem
• M>F
• Presents with palpable purpura on buttocks and legs
• GI pain and bleeding
• Hematuria due to IgA nephropathy
• Polyarthritis
• Usually occurs following a URI: Group A strep  

• Unknown etiology (95%)
• Risk factors include age, race (increased in African Americans, decreased risk in Asians), obesity, stress, lack of physical activity, and high salt diet  

• HTN due to identifable etiology (5%)
• Renal Artery Stenosis:
• Stenosis decreases blood flow to glomerulus
• Juxtaglomerular appratus (JGA) responds by secreting renin which converts to angiotensinogen to angiotensin I
• Angiotensin I is convereted to angiotensisn II by angiotensin converting enzyme
•  Angiotensin II raises blood pressure by:
• Contracting arteriolar smooth muscle increasing total peripheral resistance
• Promoting adrenal release of aldosterone which increases resorption of sodium in the distal convuluted tubule which expands plasma volume
• Leads to HTN wiht increased plasma renin and unilateral atrophy of the affected kidney
• Imporatant causes of stenosis include atherosclerosis (elderly males) and fibromuscular dysplasia (young females)
• Fibromuscular dysplasia is developmental defect of the blood vessel wall resulting in irregular thickening of the large and medium sized arteries, especially the renal artery.

Mild or moderate elevation in BP

Most cases of HTN are benign

Clinically silent, vessels and organs are damaged slowly over time

BP > 200/120 mmHg

May Arise from benign HTN or denovo

Presents with actue end organ damage and is a medical emergency

• Intimal plaque that obstructs blood flow
• Consists of a necrotic lipid core (mostly cholesterol) with a fibromuscular cap
• Often undergoes dystrophic calcification
• Involves large and medium sized arteries: Abdominal aorta, coronary arteries, popliteal artery, and internal carotid artery
• Modifable risk factors:
• Hypertension
• Hypercholeterolemia
• Smoking
• Diabetes
• Nonmodifable risk factors:
• Age: Increased
• Sex: Male, and postmenopausal women (estrogen is a protective factor)
• Genetics: Family history
• Pathogenesis:
• Damage to the endothelium allows lipids to leak into the intima
• Lipids are oxidized and then consumed by macrophages via scavenger receptors resulting in foam cells
• Inflammation and healing leads to deposition of extracellular matrix and proliferation of smoot muscle
• Morphological stages
• Begins as a fatty streak
• Flat yellow lesion of the intima consisting of lipid lagen marchophages
• Arise early in life-present in most teenagers
• Progress to athersoclerotic plaque
• Complications of atherosclerosis accounts for > 50% of disease in western countries
• Stenosis of medium sized vessels results in impaired blood flow and ischemia leading to
• Peripheral vascular disease: lower extremitiy arteries- popliteal
• Angina: Coronary arteries
• Ischemic bowl disease: Mesenteric arteris
• Plaque rupture with thrombosis results in MI (coronary arteries) and stroke (MCA)
• Plaque rupture with embolization results in atherosclerotic emboli characterized by cholesterol crystals within the embolus
• Weakening of vessel wall results in aneurysm (abdominal aorta)

• Narrowing of small arterioles
• Hyaline arteriolosclerosis
• Caused by proteins leaking into the vessel wall producing vascular thickening
• Proteins are seen as pink hyaline in microscopy
• Consequence of long standing hypertension or diabetes
• Results in reduced vessel baliber with end organ ischemia
• Classically produces glomerular scarring that slowly progressesto chronic renal failure
• Hyperplasic Arteriolosclerosis
• Involves thickening of vessel wall by hyperplasia of smooth muscle
• Onion skin appearance
•  Results in reduced vessel caliber with end organ ischemia
• May lead to fibrinoid necrossi of the vessel wall with hemorrhage
• Classically causes acute renal failure with a characteristic flea-bitten appearance

• Calcification of the media of muscular (medium sized) arteries
• Nonobstructive
• Not clinically significant
• Usually seen as an incidental finding on x-ray or mammography  

• Intimal tear with dissection of blood through the media of the aortic wall
• Occurs in the proximal 10 cm of the aorta (high stress region) with preexisting weakness of the media
• Most common cause is hypertension in older adults
• Hypertension results in hyaline arteriosclerosis of the vasa vasorum and decreased flow cause atrophy of the media
• Inherited defects of connective tisue in younger adults
• Marfan Syndrome
• Ehlers-Danlos
• Increased risk for pregnant women
•  Presents as sharp, tearing chest pain that radiates to the back
• Complications include pericardial tamponade (MC cause of death), rupture with fatal hemorrhage, and obstruction of branching arteries (coronary and renal) with resultant end organ damage

• Ballon-like dilation of the thoracic aorta
• Due to weakness in the aortic wall
• Classically seen in tertiary syphilis, endarteritis of the vasa vasorum results in luminal narrowing, decreased flow, and atrophy of the vessel wall
• Tree Bark appearance of the aorta
• Major Complication is dilation of the aortic valve root resulting in aortic valve insufficiency
• Can also cause compression of mediastinal structures (airway or esophagus) and thrombosis or embolism  

• Balloon like dilation of the abdominal aorta
• Usually arises below the renal arteries but above the aortic bifurcation
• Primarily due to athersclerosis
• Classically seen in male smokers > 60 yrs olf with hypertension
• Presents as a pusatile abdominal mass that grows with time
• Major complication is rupture especially when > 5cm in diameter
• Presents with a triad of hypotension, pulsatile abdominal mass, and flank pain
• Other complications include compression of local structures (ureter) and thrombosis and embolism  

• Benign tumor of comprised blood vessel
• Commonly present at birth and often regresses during childhood
• Most often involves the skin and liver 

• Low grade malignany proliferation of endothelial cells
• Associated wtih HHV-8
• Presents as purple patches and nodules on the skin
• May also invovle visceral organs
• Classically seen in:
• Older Eastern European makes- tumor remains localized to skin.  Treatment involves surgical removal
• AIDS- tumor spreads early.  Treatment is antiretroviral agents to boost immune system
• Transplant reciepents- Tumor spreads early. Treatment involves decreasing immunosupression