Week 3: CV pathology diseases of blood vessels I & II Flashcards
Describe capillary vascular malformations.
- malformed dilated capillaries in skin. Not a neoplasm.
- usually present at birth, vary in size, grows in proportion to child’s growth
1. Nevus simplex (macular stain) - aka salmon patch,stork bite, angel kiss
- blanchable pink-red patches
- common at nape of neck, forehead between eyebrows, eyelids
- most disappear within 1st year of life
- may be more intense with crying
2. Naevus Flammeus - “port wine”
- common in head/neck, dermatomal dist. for facial lesions
- pink to red macules at birth, persist and darken with age, may become ticketed, irregular and nodular
Describe hemangiomas of Infancy (HOI)
- benign vascular neoplasm
- 50% present at birth as red macule,papule, 50% appear in first few months of life
- 2/3 in head/neck
- Two phases: rapid growth for 6-12 months, then slow involution over years
- most follow benign course
- can have visceral involvement
Describe venous malformations.
- superficial or deep
- pain common, esp with deeper lesions.
- venous stasis and activation of altered endothelium may cause localized coagulopathy–>phlebothrombosis common
Descrive arteriovenous malformations (AVM).
- abnormal communication between artery and vein that bypasses capillary bed
- brain is most common site, greatest clinical significance. Can hemorrhage, cause seizure, headache, progressive neurological deficit
- In large AVMs, can have high output cardiac failure from decreased peripheral resistance and compensatory increase in SV and CO
Describe lymphatic malformations.
- commonly occurs as lymphatic-venous malformations or capillary-lymphatic malformations
- cervicofacial and axilla region most common
- can be associated with trisomy 13,18,21 and Turner syndrome
Describe coarctation of the aorta.
- narrowing of the aorta at the level of ductus arteriosis/ligamentum arteriosum
- Two types:
1) pre-ductal (infantile): less common and more severe. Narrowin is proximal to ductus arteriosus, heart failure in early life often. patent ductus arteriosus.
2. )post ductal (adult): less severe. narrowing is distal to ligamentum arteriosum. Hypertension in upper body and weak pulses/hypotension in lower with potential ischemia. Large intercostal arteries as collateral circulation.
Describe hereditary hemorrhagic telangiectasia.
- autosomal dominant vascular disorder that manifests later in life, not congenital, genetically predetermined
- variety of manifestations
- diagnostic criteria: epistaxis, telangiectasias, visceral history, family history
- can have secondary iron deficiency anemia
List in descending order from the most severely affected, the vessels affected by atherosclerosis and their major clinical consequences.
- abdominal aorta-aneurysm
- proximal coronary artery - MI, chronic ischemic heart dz
- descending thoracic aorta - aneurysm
- popliteal artery -gangrene
- internal carotid artery - cerebral infarct
- circle of willis vessels- cerebral infarct
What are complicated lesions (atherosclerosis)?
-advanced plaques that undergo certain changes which are particularly significant clinically, including: focal erosion, ulceration or rupture of fibrous cap–>thrombosis and micro emboli, hemorrhage, aneurysmal dilation, calcification
Describe the fatty streak in atherosclerosis?
- aggregates of foam cells (LDL in macrophages), T cells, SMCs, aggregated platelets
- 1st grossly visible lesion in development of atherosclerosis
What is atherothrombosis?
-atherosclerotic plaque disruption with superimposed thrombosis (leading cause of mortality in Western world)
Define aneurysm.
=pathologic dilution of a segment of a blood vessel or wall of the heart
- True aneurysm=dilation of all three intact, but often attenuated vessel wall layers
- false aneurysm=rupture of the intimal and medial layers, with resulting dilation created by extravasation of blood into the adventitia
What are 3 subtypes of aneurysm, based on shape or location or cause.
- Abdominal aortic aneurysm: most common. mostly caused by advanced atherosclerosis with erosion of IEL and plaque expansion leading to medial destruction. Or caused by connective tissue disease. Saccular or fusiform.
- Mycotic aneurysms: infection of vessel wall, mostly caused by septic embolus in infective endocarditis. Also secondary to neighboring bacterial infection.
- Syphilitic: tertiary syphilis.
What are 3 different shapes of aneurysms?
- saccular: assymmetric, spherical
- berry: small intracranial saccular aneurysms. develops over time due to underlying congenital weakness of vessel media
- fusiform: progressive, symmetrical dilation of complete vessel circumference.
Describe aortic dissection. Risk factors?
- definition: intimal tear allowing blood to enter vessel wall and dissect along laminar planes of aortic media, forming false channel.
- plane of dissection: outer 1/3 of media–> weakened external wall can lead to rupture
- common site: ascending aorta above aortic ring, then descending aorta below ligamentum arteriosum
- risk factors: age>70, hypertension, male, atherosclerosis, connective tissue disease
- major complications: acute aortic regurg, MI, cardiac tamponade from rupture into pericardium, potential cerebral/renal/mesenteric infarct
