PATHO - Blood Vessels 2 (Aneurysms, Dissection, Arteritides)

ECM weakness

What general pathology causes aneurysm formation due to compromised vessel wall connective tissue?

Ehlers-Danlos syndrome

Defective collagen III synthesis occurs in what disorder?

Marfan syndrome

Defective fibrillin synthesis occurs in what disorder?

Vitamin C deficiency

Vitamin deficiency causing altered collagen cross-linking?

TGF-beta dysfunction

What signaling abnormality causes decreased ECM content and activity?

Loeys-Dietz syndrome

Mutation of TGF-β receptors I & II occurs in what disorder?

MMPs

Increased proteolytic enzymes degrading ECM are known as what?

TIMP

The tissue inhibitor of metalloproteinases is abbreviated as what?

Intimal thickening

What process causes ischemia in atherosclerosis-related aneurysms?

Vasa vasorum

Hypertension-related ischemia occurs due to narrowing of what vessels?

Ground substance

Loss of smooth muscle cells leads to increased production of what matrix material?

Cystic medial degeneration

What histologic change is defined by ECM-rich spaces in the media?

Septic emboli

Name one infectious cause of vascular wall weakening.

Atherosclerosis

What are the two most important disorders predisposing to aortic aneurysm?

Hypertension

What other major disorder predisposes to aortic aneurysm besides atherosclerosis?

True aneurysm

Aneurysm containing all vascular wall layers is called what?

False aneurysm

Aneurysm with only periarterial tissue containment?

Dissection

Leakage of blood into media forming a new channel is called what?

Saccular aneurysm

Spherical aneurysm 5–20 cm is termed what?

Fusiform aneurysm

Circumferential dilation of a vessel wall is called what?

Men

Most AAAs occur in which sex?

Smoking

Major lifestyle risk factor for AAA?

>50 years

Typical age group for AAA occurrence?

Atherosclerosis

Most important cause of abdominal aortic aneurysm?

CD4 T cells

Main inflammatory cells in AAA development?

IL-4

TH2 cytokine promoting AAA inflammation?

MMPs

Enzymes degrading elastin and collagen in AAA?

Renal arteries

AAA most frequently appears below which arteries?

Vasa vasorum

AAA blood supply weakness arises from limited what structure?

Nitric oxide

Increased turbulence in infrarenal aorta stimulates release of what vasodilator?

Infrarenal aorta

Most common location of AAA relative to renal arteries?

Fusiform

Typical shape of AAA?

15-25 cm

Diameter range of severe AAA?

Atheromatous ulcer

What plaque-associated lesion appears inside AAA?

Thrombosis

What complication forms inside AAA due to stasis?

Pulsatile mass

Classical physical exam finding in AAA?

Ureter

AAA may compress which organ leading to hydronephrosis?

Mesenteric arteries

Occlusion of which arteries may cause bowel ischemia?

Flank pain

Classic symptom of ruptured AAA?

Shock

Rupture of AAA typically leads to what emergency?

Thickened wall

Key gross feature of inflammatory AAA?

Perianeurysmal fibrosis

What retroperitoneal change may entrap ureter or duodenum?

Males

Demographic most associated with inflammatory AAA?

No

Are most mycotic aneurysms fungal in origin?

Hematogenous spread

Most common mechanism of mycotic AAA infection?

Staphylococcus aureus

Most common bacteria causing mycotic AAA?

Salmonella

Gram-negative organism associated with mycotic AAA?

40-60 years

Typical age for aortic dissection in hypertensives?

Connective tissue disorder

Aortic dissection in young patients suggests what defect category?

Hypertension

Major risk factor for aortic dissection?

Marfan syndrome

Disease involving defective TGF-β signaling increasing dissection risk?

Intimal tear

What lesion provides entry point for blood in dissection?

Cystic medial degeneration

What medial lesion is commonly found in dissection?

Vasa vasorum

Spontaneous rupture of what vessel leads to intramural hematoma?

Aortic root

What structure displacement during cardiac cycle increases ascending aortic stress?

Ligamentum arteriosum

What aortic region’s fixed point predisposes to tears?

10 cm

Usual distance of intimal tear from aortic valve?

1-5 cm

Length of typical intimal tear?

Double-barreled aorta

What appearance results when blood re-enters aortic lumen?

Ascending aorta

Type A dissection involves which aortic region?

Subclavian artery

Type B dissection begins distal to which artery?

Sudden chest pain

Classic symptom of dissection?

Rupture

Most common cause of death in dissection?

Cardiac tamponade

Rupture into pericardium causes what lethal condition?

AAA

Which is more common: AAA or TAA?

Cystic medial degeneration

Age-related degenerative changes in aorta cause what pathology?

Marfan syndrome

Which connective tissue disorder causes TAA?

Syphilis

Which infection historically caused TAA?

Bicuspid valve

What congenital aortic valve abnormality predisposes to TAA?

Dysphagia

Compression of esophagus by TAA causes what symptom?

Hoarseness

TAA compressing recurrent laryngeal nerve causes what?

Pain

Erosion into bone from TAA causes what complaint?

Aortic insufficiency

Aortic root aneurysm leads to what valve problem?

Infectious organisms

Direct vessel invasion is most commonly caused by what category?

Neutrophils

Vessel wall immune complexes activate what complement cells?

ANCA

What autoantibodies directly activate neutrophils?

Myeloperoxidase

Perinuclear ANCA targets what enzyme?

Proteinase 3

Cytoplasmic ANCA targets what enzyme?

Ischemia

What vascular complication results from luminal occlusion?

Hemorrhage

Destruction of vessel walls causes what consequence?

Fever

Name one constitutional symptom common in vasculitis.

Dendritic cells

What antigen-presenting cells initiate giant cell arteritis?

Th1 cells

What T-cell subset produces IFN-γ in GCA?

IL-17

Cytokine produced by Th17 cells in GCA?

Intimal hyperplasia

PDGF in GCA causes what change?

Granulomas

Most common histologic feature in GCA?

Elastic lamina

Fragmentation of what structure is characteristic in GCA?

Giant cells

What cell type forms multinucleated lesions?

>50 years

Most common vasculitis in what age group?

Blindness

Worst complication related to ocular ischemia?

Polymyalgia rheumatica

What condition often coexists with GCA causing shoulder pain?

Heat shock protein

What vascular protein induces MICA expression?

NK cells

What cells release perforin causing endothelial apoptosis?

IFN-gamma

Cytokine driving giant cell formation in Takayasu disease?

Aortic arch

Classic vessel involved in Takayasu arteritis?

Granulomatous

What type of inflammation characterizes Takayasu arteritis?

15-40 years

Age group commonly affected in Takayasu arteritis?

Weak

Pulses in upper extremities are typically what?

Hypertension

Stenosis of renal arteries causes what condition?

Glomeruli

PAN spares what vascular structures?