Cardiovascular 1 Flashcards
3 layers of a muscular artery?
intima, media, adventitia
What is the term describing the thickening and hardening of arterial walls?
Arteriosclerosis
Does arteriosclerosis imply a cause?
no
Arteriosclerosis effects on:arterial lumen
blood flow
elasticity
lumen narrowerblood flow and elasticity decreased
Arteriolosclerosis affects what?
Small arteries and arterioles, esp. kidneys
Arteriolosclerosis - what kinds of changes to walls?
Hyaline thickening & hardening, proliferation
Arteriolosclerosis - condition of wall?
Wall usually completely effaced, destruction of SMC layer
Arteriolosclerosis - most frequently caused by?
systemic hypertension or diabetes mellitus
Atherosclerosis - affects what vessels
large and medium arteries, NOT veins
small arteries show signs of arteriosclerosis from hypertension
Atherosclerosis begins with damage to…Then leads to…
tunica intimadamage, thickening and hardening of tunica media
Most common cause of arteriosclerosis of medium and large-sized arteries
atherosclerosis
Atherosclerosis increases risk of (2)
thrombus formation, aneurysm
Atheroma is what? Found where?
Fibrous, lipid-rich plaques in intima of high-pressure arteries
Atheromas especially found in what vessels (6)
Coronary Carotid Circle of Willis Legs (large vessels) Renal Mesenteric
Where are atheroma NEVER found unless in hypertension?
Pulmonary arteries
Atheroma composition - 2 layers, 4 things in each layer?
Central core:1. cholesterol 2. foam cells (macrophages) 3. Calcium 4. necrotic debris Subendothelial fibrous cap 1. SMCs 2. foam cells 3. Fibrin 4. ECM
What is a fatty streak?
focal accumulation of foam cells in intima
Fatty streaks appear as early as…
first year of life
Atheroma formation steps (4)
- foam cells accumulate
- myofibroblasts proliferate and secrete collagen –> plaque now fibrotic and under pressure
- fibrous cap forms
- collagenization of media
Consequences of atheromas (6)
- Restrict blood flow
- Hemorrhage
- Calcification
- Thrombus/embolization
- Ulceration
Consequences of atherosclerosis
- ischemic heart disease/MI
- ischemic renal disease
- ischemic bowel disease
- thrombus/stroke/peripheral vascular disease
- aneurysm
Risk factors for atherosclerosis
- age
- male or menopausal women
- Familial
- high cholesterol
- htn
- diabetes
- smoking
Normal ratio of Total/HDL cholesterol?LDL/HDL?
Total/HDL
How does HDL “protect” against atherosclerosis
removes cholesterol from tissues and plaques
What is the primary event leading to pathogenesis of atherosclerosis?
chronic, low-grade injury or dysfunction of arterial endothelium
Response to injury triggering atherosclerosis can be due to (6)
- hypercholesterolemia
- mechanical injury
- hypertension
- immune mechanisms
- toxins
- viruses
What happens after the initial primary event in athersclerosis (reaction to injury)?
Entry of monocytes and lipids into subendothelium–> mitogenic factors released –> proliferation
Definition of aneurysm
abnormal focal dilation of artery or vein
Main complications of aneurysms
- erode adjacent structures
- rupture
- predisposition to thrombosis
Atherosclerotic aneurysm most common site?
abdominal aorta
Berry aneurysm found where?
cerebral arteries
Berry aneurysm cause? Related to atherosclerosis at all?
congenital defect in elastic lamina
NOT related
Berry aneurysm leads to
intracranial bleeding
Dissecting aneurysm is A?
longitudinal tear in intima that leads to a second arterial lumen, NOT a true aneurysm
Dissecting aneurysm most commonly in…
aorta
Predisposing factors of dissecting aneurysm
- Hypertension2. medial mucoid degeneration (marfan & ehlers-danlos syndromes)3. atherosclerosis4. instrumentation of artery
Dissecting aneurysm sign?
tearing chest pain radiating through to back
If a dissecting aneurysm ruptures, what 3 things might happen?External rupture…Retrograde spread…Internal rupture…
External rupture…massive fatal hemorrhage into thoracic
Retrograde spread…fatal hemopericardium
Internal rupture…double-channeled aorta
Hypertension is when diastolic BP is below
90mmHg
Htn can be benign when…
stable increase
Htn is malignant when…
severe elevation over short period of time
What is primary hypertension?
aka essential. Elevation of BP over age
Determinants of primary Htn (7)
(1) genetics - African
(3) diet - obesity, sodium, alcohol
(3) lifestyle - inactivity, smoking, stress
Primary htn can predispose to…
ischemic heart diseasestroke
Primary htn will lead to what if left untreated (3)
retinal changesleft ventricular hypertrophy & heart failurebenign nephrosclerosis
Secondary htn means it is due to..
OTHER CAUSES
Most common cause of secondary htn?
renal disease
Benign type hypertension leads to what changes in vessels?
Wall thickening, lumen thinning
tissue ischemiabrain vessel fragility
hemorrhage
Malignant htn leads to (3)
destructive changes & proliferative response in intima
cessation of blood flow through small vessels
foci of tissue necrosis
Malignant htn results in…
death through CHF, CVA, kidney failure
Malignant htn % cases of htn
5%
Htn pathology in brain?
rupture & microinfarcts/hypertensive lacunae
Htn pathology in heart?
left ventricular hypertrophy & failure
Htn pathology in kidney?
arteriosclerosis –> leads to progressive destruction of nephrons –> renal failure, benign hypertensive nephrosclerosis
Htn pathology in aorta
severe atherosclerosis, abdominal and dissecting aortic aneurysms
pulmonary arterial htn is a consequence of what?
Raised left atrial/ventricular pressure due to inadequate emptying of left heart, OR dstructino of lung capillary bed
pulmonary arterial htn underlying cause?
from ischemic heart disease, aortic or mitral valve stenosis (left heart emptying failure) emphysema, fibrosis of lungs (capillary destruction)
Vasculitis is what?
inflammation and damage to vessel wall
3 groups of vasculitis?
Small - wegener’s, Churg Strauss, drug inducedMedium - polyarteritis nodosa, kawaski’slarge - takayasu, giant cell
Hypersensitivity vasculitis…type, cause?
immune complex, often because of drug allergy
Hypersensitivity vasculitis presents as what? mechanism?
skin rash due to antigen-antibody complex stuck in vessel walls promoting inflammation
Polyarteritis nodosa - destruction of what?
arterial media and internal elastic lamella –> aneurysmal nodules
Wegener’s - vasculitis of vessels of what organs?
respiratory tract, kidneys, others
Wegener’s - characterized by what type of damage?
necrotizing granulomatous vasculitis, fibrinoid necrosis
Buerger’s disease - results in what?
Acute inflammatory occlusion of small to medium-sized arteries of upper and lower limbs
Buerger’s disease related to what behavior?
heavy smoking
Buerger’s disease patients succumb to what?
peripheral vascular insufficiency
Varicose veins - presentation?
persistent, distended, and tortuous superficial veins in lower limbs
Varicose veins due to what?
valve incompetence allow them to fill due to gravity
Varicose veins predisposed by?
increased venous pressure
Esophageal varices - what are they?
distended venous channels that develop in portal hypertension secondary to cirrhosis of liver
Venous thrombosis aka?
phlebothrombosis
Venous thrombosis arises most often where?
deep veins of lower extremities
Venous thrombosis predisposed by?
venous circulatory state or partially obstructed venous return
Kaposi’s sarcoma 3 stages
patch, plaque, nodule
Kaposi’s sarcoma - causative agent?
HSV8
