Chapter 11 Blood Vessels 1. Where in the circulation is the principal point of resistance to flow? Where does vascular leakage preferentially occur? What is the process of remodeling existing arteries called? Arterioles From postcapillary venules Arteriogenesis 2. What is fibromuscular dysplasia? Why worry about it? Congenital, focal thickening of medium-large arteries like renal, carotid, splanchnic, or vertebral Renal vascular hypertension and aneurysms 3. When does a neointima form? What cells make it up? Thickening occurs after basicaly any injury Smooth muscle cells, either from circulating precursors or the tunica media 4. What causes hypertension? What are two named single gene mutations that can cause hypertension? 95% of the time it is essential hypertension, which is idiopathic Liddle syndrome: ENaC mutation causes excess reabsorption mutations like 11B-hydroxylase and 17a-hydroxylase cause too much aldosterone to be released 5. What are the morphologic signs of benign hypertension and malignant hypertension? Hyaline arteriosclerosis Fibrinoid necrosis, onion skinning 6. What is Monckeberg medial sclerosis? Insignificant calcifications in the arteries of people under 50, which sometimes turn to bone 7. What is the most significant risk factor for atherosclerosis? What is another risk factor and simple marker for inflammation? What other risk substance that may be increased by deficient folate or vitamin B12? Family history C-reactive protein Homocystine is bad at high levels 8. What are foam cells? Who gets fatty streaks? Eaters of oxidized LDL in the intima, derived from macrophages and smooth muscle cells Just about everybody by childhood 9. Where do atherosclerotic plaques like to form? Abdominal aorta, coronary arteris, popliteal arteries, internal carotids, then circle of Willis 10. When does stable angina occur? What makes a plaque vulnerable? What time of day do MIs tend to occur? At the point of critical stenosis: ~70% occlusion Thin fibrous cap, can be due to excess MMP activity or insufficient TIMPs Sympathetic circadian periodicity causes most MIs in the morning between 6 and noon 11. What are three genetic conditions that can cause aneurysms? What are two familiar causes of infectious (mycotic) aneurysm? What are the two major causes of aneurysm? Marfan, Loeys-Dietz (TGF-β receptor mutation), and Ehlers-Danlos Syphilis in the aorta, Salmonella in the AA atherosclerosis and Hypertension 12. What is the major risk factor for dissection? Others? What is the most frequent preexisting histology? hypertension i. unlike aneurysm, the medial fibrosis of atherosclerosis inhibits tear propogation the three genetic disorders above, vitamin C deficiency, copper metabolic defects most commonly aneurysms arise from no distinct lesion i. otherwise, cystic degeneration of the tunica media 13. How does the DeBakey classification correspond to dissection type? Clinical presentation? DeBakey I and II = type A = proximal lesions DeBakey III = type B = begin distal to subclavian artery tamponade, aortic insufficiency, MI, compression of spinal arteries=> transverse myelitis; death occurs if it ruptures Other Junk 14. What are the three mechanisms of noninfectious vasculitis? Immune complex deposition: drug hypersensitivity or viral protein + antibody i. E.g. hepatitis B Antineutrophil cytoplasmic antibodies: ANCAs may react with cytokine-activated cells to cause direct injury to the endothelium or further activate neutrophils Anti-endothelial cell antibodies 15. What general category of vasculitis is associated with ANCAs? What do PR3 ANCAs correspond to? What 2 diseases do MPO-ANCAs (old name is P-ANCAs) correspond to? Small-vessel Wegner granulomatosis Microscopic polyangiitis and Churg-Strauss syndrome 16. Why is giant cell (temporal) arteritis an emergency? How do affected arteries appear (2)? It can cause permanent blindness Segments of intimal thickening that constrict the vessels Large to small arteries undergo granulomatous inflammation that leads to elastic lamina fragmentation 17. What do you call a granulomatous vasculitis of medium and larger arteries, which causes peripheral weakening of the pulses and ocular disturbances? How is this differentiated from giant cell aortitis? Takayasu arteritis (“pulseless disease”) i. Principally transmural fibrous aortic thickening, especially the arch ii. Not mentioned above are neurologic disturbances, MI, pulmonary HTN, and systemic HTN If age of patient greater than 50 = giant cell aortitis; age less than 50 = Takayasu 18. What do you call vasculitis of young adults involving small to medium sized arteries in the renal and visceral vessels? What infection is associated in 30% of cases? Describe its morphology. Polyarteritis nodosa Chronic Hepatitis B; immune complexes are deposited Two coexisting stages: i. Transmural inflammation with fibrinoid necrosis ii. Fibrous thickening of the vessel walls 19. What disease is going to cause MIs and aneurysms in children? What are its other (actually more common) signs? What disease does it resemble under a low-power microscope? Kawasaki disease; caused by anti-endothelial antibodies i. Affects large-medium-small arteries, but especially coronary arteries Fever, oral erosions, edema of hands and feet, erythema of palms and soles, and desquamation Polyarteritis nodosa 20. How can the small vessel vasculitises be differentiated based on clinical signs? Microscopic polyangiitis: no asthma, no granulomas Wegener granulomatosis: no asthma Churg-Strauss: +asthma, +granulomas, and +eosinophilia 21. What disease resmbles polyarteritis nodosa, but only in small vessels and capillaries? What are its other signs? Microscopic polyangiitis: like PAN, but all lesions are of the same stage Necrotizing glomerulonephritis and pulmonary capillitis are most common Many organ systems can be involved: hemoptysis, hematuria, proteinuria, bowel pain/bleeding, muscle pain, palpable cutaneous purpura, brain involvement 22. What is Churg-Strauss syndrome? What signs are associated? What marker is seen in ~half of cases? Small-vessel necrotizing vasculitis, associated with asthma, allergies, cardiomyopathy, GI bleeds, glomerulosclerosis, hypereosinophilia, and necrotizing extravascular granulomas MPO-ANCAs 23. What triad makes up Wegener Granulomatosis (3)? What marker is almost always present? Necrotizing granulomas of the upper respiratory tract Necrotizing intravascular granulomas in small-medium vessels, mostly affecting lungs Necrotizing glomerulonephritis in the kidneys PR3-ANCAs [a “W” has three upward facing tips/sideways 3] 24. What disease causes segmental thrombosing inflammation of small-medium arteries (especially tibial and radial arteries)? What is the risk factor? What are some associated clinical signs? Thromboangiitis obliterans (Buerger disease) Smoking Raynaud phenomenon, instep claudication, chronic ulcerations of extremities, and pain 25. What is the consequence of varicose veins? Stasis dermatitis [think: Winston scratching his varicose ulcer in 1984] 26. What two fungi species often cause vasculitis? Mucor and Aspergillus Makes you prone to mycotic aneurysm 27. What is the pattern of Raynaud’s phenomenon? What conditions can cause secondary Raynaud’s phenomenon? Proximal=> distal: red, white, & blue SLE, scleroderma, Buerger disease, or atherosclerosis 28. Besides the Deep Veins, where can thromboses arise? What is a funny cause of hypercoagulability? Dural sinuses and veins in the skull, periprostatic venous plexus, and pelvic venous plexus in females Neoplasia—remember the Trousseau sign (migratory thrombophlebitis)? 29. What causes inferior vena caval syndrome? Neoplasms like hepatocellular carinoma or renal cell carcinoma Thrombus from lower extremities that propogates upward 30. What disease causes primary lymphedema? When does lymphangitis occur? Milroy disease causes lymphatic agenesis or hypoplasia, resulting in lymphedema infection 31. What kind of hemangioma does not spontaneously regress? What disease are they associated with? What kind often appears after trauma or pregnancy? What is a cystic hygroma? Cavernous; i. occur in the CNS (brain stem, cerebellum, and retina) in Von Hippel-Lindau disease, which has similar pancreatic and liver neoplasms Pyogenic granuloma (called “granuloma gravidarum” or pregnancy tumor; form in gingiva in pregancy) Cavernous lymphangioma; common in Turner syndrome 32. What is a glomus tumor? What is Sturge-Weber syndrome? What is another name for hereditary hemorrhagic telangiectasia? Painful tumor arising around or under the fingernails; from thermoregulator specialized smooth muscle cells Congenital syndrome associated with Facial port wine nevi, mental retardation, angiomatous masses in the meninges, and hemiplegia [think of a nevus in the shape of a retarded sturgeon] Osler-Weber-Rendu disease; the dangers are nose, GI, and urinary bleeding 33. What hormone can cause formation of spider angiomas? Estrogen—pregnancy and cirrhosis 34. What two microbes cause bacillary angiomatosis? Bartonella henselae (cat scratch disease) and B. quintana (trench fever), usually in an immunocompromised host => vascular proliferation in the form of raised red papules and nodules or subcutaneous masses 35. What can Kaposi sarcoma help you diagnose? What does it look like? Who gets chronic KS? Which version is the most common tumor in central Africa? What is the causative agent? AIDS Multiple red-purple plaques in distal extremities which spread from the distal extremities inward and increase in number Ashkenazi Jews or Mediterraneans Lymphadenopathic KS, associated with Burkitt lymphoma Human Herpes Virus 8 (KSHV), a gamma herpesvirus 36. What vascular tumor occurs around big veins? What malignant tumor occurs around capillaries and venules? Epitheliod hemangioendothelioma Hemangiopericytoma 37. What toxins cause angiosarcoma in the liver? What is another cause of angiosarcoma elsewhere? What is interesting about the histology of angiosarcoma? Arsenic, thorotrast, and polyvinyl chloride (actually the vinyl chloride monomer) Lymphedema, especially that which occurs after mastectomy All degrees of differentiation can be seen, as well as endothelial origin 38. What needs to be given during angioplasty and stenting? Why are left internal mammary artery grafts better than autologous saphenous vein? Antiplatelet agents More likely to remain patent