cvs lec 1.pdf , cardiovascular system and pathology

Cvs

1. Blood vessels

2. ARTERIOSCLEROSIS
•Arteriosclerosis (“hardening of the arteries”) is
characterized by arterial wall thickening and may
be caused by:
1. Arteriolosclerosis: It affects small arteries and arterioles
. 2. Mönckebergmedial sclerosis: It is characterized by
deposition of calcium in muscular arteries seen in old age (above
50 years).
3. Atherosclerosis: It is the most frequent and important disease
of intima.

3. ATHEROSCLEROSIS

4. Definition
•Atherosclerosis is the deposition of fibrofatty
material in tunica intima of large to medium
sized vessels

6. Major steps in atheroma formation
Normal
Endothelial injury/dysfunction with adhesion of monocyte
Migration of monocyte into arterial intima and convert into macrophages
They engulf lipoprotein and oxidized LDL to form foam cells
Migration of smooth muscle followed by their proliferation in intima
Fully developed atheromatous plaque

8. Atheroscclerosis
•Microscopy
Three main components in varying proportions in different
lesions:
1. Cells: Smooth muscle cells, macrophages, and T-cells.
2. Extracellular matrix (ECM): Collagen, elastic fibers, and
proteoglycans.
3. Lipid: Both intracellular and extracellular lipid

9. Fatty streaks
•Gross feature
Yellowflatmacules
•Microscopic Features
Vaculatedmacrophages in tunica intima

10. Atherosclerotic plaque
Gross features
•white toyellowraisedlesions
•Eccenteric/focaloncutsectionofvessel
Microscopic features
Superficial fibrous cap →smooth muscle cells,densecollagen
Lipidnecroticcore→Extracellularlipid,intracellularlipid(foam
cells),necrotic debris,thrombiand fibrin
Additional features:Neovascularizationand dystrophic calcification

13. Fatty steak

15. Major vessels involved in atherosclerosis in descending order
are:
•Lower abdominal aorta (abdominal aorta more than the
thoracic aorta)
•Coronary arteries
•Popliteal arteries
•Internal carotid arteries
•Vessels of the circle of Willis.

16. Complications of atherosclerosis:
•1. Rupture
•2. Hemorrhage into the plaque
•3. Thrombosis
•4. Embolism
•5. Aneurysm
•6. Calcification.

19. Major clinical consequences of atherosclerosis

20. Aneurysm

24. Definition
•An aneurysm is defined as a congenital or
acquired, localized, abnormal, permanent
dilation of a blood vessel or the heart

25. Morphological types of aneurysm:
1. Fusiform
2. Saccular
3. Cylindrical
4. Aortic dissection.

26. Microscopic features
•Atheroseclrosis
•Thinning oftunicamedia
•Dilation plus thrombus
•Inflammatory abdominal aortic
aneurysm(lymphocyte,plasmacells,giantcells,fibrosis)
•Mycotic aneurysm(infective endocarditis)

27. Predisposition Factors
•1.Atherosclerosis: It predisposes to aneurysms in the
abdominal aorta.
•2. Hypertension: It predisposes to aneurysms of the
ascending aorta
•3.Trauma
•4.Vasculitis
•5.Congenital defects (e.g. berry aneurysms in the circle of
Willis)

28. •6.Tertiary syphilis: It is a rare cause of aortic aneurysms.
Trepenomashas affinity for vasa vasorum of mainly thoracic
aorta obliterative endarteritis leads to ischemic damage to the
aortic media and aneurysm (syphilitic mesoaortitis)
•7. Infections (mycotic aneurysms):

29. Causes of abdominal aorta aneurysm
•Atherosclerotic AAA(most common cause)
•Inflammatory AAA
•Mycotic AAA

30. Aortic dissection

32. Gross
•Tear in tunica intima
•Double barreled aorta

33. Microscopic features
Cystic
Cystic space in
tunica media
Medial
degeneration
Smooth muscle
cells dropout and
necrosis
Elastic tissue
fragmentation
Replaced by
amorphous
proteoglycan of
ECM

36. Hypertention

39. Hypertensive
vascular
disease
Small vessel
disease
Hyalin
arteriosclerosis
1.Eosinophilic
and hyaline
material in
intima media
2.Luminal
narrowing
Hyperplastic
arteriosclerosis
1.Onion skin
appearance
2.Concentric
hyperplastic
layers of
smooth muscle
Necrotising
arteriolitis
1.Fibrinoid
deposits
2.Vessel wall
necrosis
3.macrophages
Medium and large vessel
disease
1.Atherosclerosis
2.Degenrative changes