11 Blood vessels

Question 1

What are the consequences of atherosclerotic disease?

Answer 1

Atherosclerotic stenosis/occlusion
Acute plaque change
Thrombosis
Vasoconstriction
Aneurysm

Question 2

What are the types of acute plaque change?

Answer 2

Rupture/fissuring
Erosion/ulceration
Hemorrhage into the atheroma

Question 3

What determines plaque stability?

Answer 3

Intrisinc factors: composition of plaque (foam cells, lipid), fibrous cap, inflammatory cells, expression of MMP and TIMPs
Extrinsic factors: statin use, systemic blood pressure, adrenergic tone, emotional stress, chronic inflammatory state

Question 4

Contrast true aneurysms from false aneurysm.

Answer 4

True aneurysm arise from a dilation of the arterial or ventricular wall and include syphilitic, atherosclerotic and congenital vascular aneurysms. False aneurysms result from a defect in the vessel wall theat results to extravascular hematoma and includes post-MI ventricular rupture with pericardial enclosure, or suture leaks following vascular surgery.

Question 5

By what mechanism do aneurysms arise?

Answer 5

Weakened vascular wall connective tissue (Marfan, EDS, Vit C)
Imbalance between collagen degradation and synthesis (inflammation, MMP and TIMP balance)
Loss of smooth muscle cells (ischemia by atherosclerosis)
Increased synthesis of non-muscular and non-elastic extracellular matrix (inflammation, atherosclerosis, hypertension)

Question 6

What are diseases characterised by defective vascular wall connective tissue?

Answer 6

Marfan syndrome
Loeys-Dietz syndrome
Ehlos-Danlos disease

Question 7

What are the consquences of AAA?

Answer 7

rupture with hemorrhage
obstruction of branch vessel
embolism
impeingement on adjacent structure
abdominal mass simulating tumour

Question 8

What are predisposing factors to aortic dissection?

Answer 8

Hypertension
Connective tissue disorders (Marfans)
Iatrogenic - previous cannalisation
Sudden deceleration
Pregnancy

Question 9

What are the major pathogenic mechanisms for vasculitis?

Answer 9

Immune mediated
Infectious
Radiation
Mechanical injury
Toxins

Question 10

What are causes of secondary obstructive lymphedema?

Answer 10

malignant tumours
lymph node dissection
post-irradiation fibrosis
filariasis
post-inflammatory thrombosis and scarring

Question 11

What are some types of hemangioma?

Answer 11

Capillary hemangioma
Cavernous hemangioma
Cherry hemangioma
Pyogenic granuloma