Atheroma, hypertension, cardiovascular risks

Question 1

What is the aetiology of atheroma?

Answer 1

cigarette smoking, hypertension, hyperlipidaemia, diabetes, age (older), sex (males), genetics

Question 2

What is the 4 steps in developing atheroma?

Answer 2

1- Primary endothelial injury. (smoking, hypertension, hyperlipidaemia, immune factors, toxins, viruses
2- accumulation of lipids and macrophages (increase LDL, reduced HDL)
3- migration of smooth muscle cells (PDGF, FGF, TGFalpha)
4- increase in size

Question 3

How does atheromatous plaques progress?

Answer 3

• Fatty streak, fibrofatty plaque, complicated plaque-with thrombus
• loss of luminal patency and arterial wall weakness

Question 4

What are the three things that will leads to atheromatous narrowing leading to a critical disease?

Answer 4

• only artery supplying an organ tissue
• the artery diameter is small
• overall blood flow is reduced

Question 5

What is the role of macrophages in the formation of athersclerotic plaque?

Answer 5

macrophages take up oxidised LDL-C

Question 6

What are the 5 major classes of lipoproteins?

Answer 6

VLDL, IDL, LDL-atherogenic

VLDL and chylomicrons- non atherogenic

Question 7

What is the endogenous pathway of lipid metabolism?

Answer 7

1-chylomicrons transport triglyceride from gut to the liver,

2-triglyceride/cholesterol/cholesterol ester and other lipoproteins are transported in vldl in the blood stream where VLDL undergoes delipidation with the enzyme lipoprotein lipase
3-
this is an endogenous pathway of lipid metabolism

Question 8

Exogenous pathway of lipid metabolism?

Answer 8

transport and utilises dietary fat.
dietary fat is broken down in the GI tract into cholesterol, fatty acids and mono-glycerides. these molecules together with bile acds, form water soluble micelles that carry the lipid to absorptive site in duodenum

Question 9

how do statins work to lower cholesterol levels?

Answer 9

• inhibit HMG coA reductase, the enzyme involved in the rate limiting step in the formation of cholesterol.
• in response- hepatocytes increase LDL receptors uptake of LDL and LDL precursors from the plasma. this increases HDL level.

Question 10

What are the consequences of high lipid levels?

Answer 10

xanthelasma
tendon xanthomas
eruptive xanthomas

Question 11

What are the complications of atheroma?

Answer 11

arterial stenosis 
arterial thrombosis
aneurysm 
dissection 
emoblism

Question 12

What is cardiac fibrosis ?

Answer 12

loss of cardiac myocytes
replacement by fibrous tissue
loss of contractility
reduced elasticity and filling

Question 13

what is an aneurysm?

Answer 13

abnormal and persistent dilatation of an artery due to an weakness in its wall

Question 14

Complication of an aneurysm ?

Answer 14

rupture 6cm
thrombosis 
emoblism 
pressure erosion of adjacent structures 
infection

Question 15

What is an arterial dissection?

Answer 15

• splitting within the media by flowing blood
• middle age +/- atheroma
• false lumen filled with blood within the media
• sudden collapse and high mortality

Question 16

What are some associations with aortic dissections?

Answer 16

marfans syndrome
trauma
pregnancy
atheroma
hypertension

Question 17

What are the main sites of infarct for an embolism?

Answer 17

-cerebral infarct
renal infarct-renal failure
lower limb infarct

Question 18

What blood pressure is expected in hypertension?

Answer 18

> 140/90

Question 19

Risk factors for hypertension?

Answer 19

cerebral haemorrhage
atheroma
renal failure
sudden cardiac death

Question 20

primary hypertension due to?

Answer 20

-genetic factors 
salt intake 
-protein intake 
-raas system 
-sympathetic activity BP=TPR X CO

Question 21

Secondary hypertension?

Answer 21

underlying disease is implicated such as:

• renal disease
• endocrine disease
• aortic disease
• renal artery stenosis
• drug therapy

Question 22

give examples of renal causes?

Answer 22

reduced renal blood flow
excess renin release
salt and water overload

Question 23

Endocrine causes, conns syndrome is?

Answer 23

excess aldosterone

Question 24

cushing syndrome causes secondary hypertension due to?

Answer 24

excess corticosteroids

Question 25

does coartaction of the aorta lead to secondary hypertension?

Answer 25

congenital narrowing of segments of the aorta, yes.

Question 26

what is benign hypertension

Answer 26

cause of serious life threatening morbidity

Question 27

What is malignant hypertension?

Answer 27

serious life threatening condition, diastolic pressure >130-140
-develops from benign primary or secondary hypertension.
needs urgent treatment to prevent death