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Flashcards in Atheroma formation Deck (38)
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1
Q

what are the types of risk factors for atherosclerosis?

A

unmodifiable

modifiable

2
Q

unmodifiable risk factors for atherosclerosis

A

ageing
genetics
ethnicity
gender

3
Q

effect of genetics on atherosclerosis risk

A

fibrinogen clotting factor disorders
lipid disorders
unlikely to be a single gene disorders although family history is strong predictor

4
Q

effect of ethnicity on atherosclerosis risk

A

asians are at greater risk of heart disease and african and caribbeans have a higher risk of hypertension

5
Q

effect of gender on atherosclerosis risk

A

men more at risk than women as oestrogen acts as protective factor until menopause then equal risk

6
Q

modifiable risk factors for atherosclerosis

A
smoking
alcohol
diabetes
hypertension
obesity
raised cholesterol
physical inactivity
metabolic syndrome - abdominal girth
hyperglycaemia
7
Q

pathogenesis of atherosclerosis

A
  1. endothelial dysfunction
  2. LDL accumulation and oxidation in walls of arteries which damages endothelium
  3. macrophages - foam cells when they phagocytose LDL and T cells recruited
  4. inflammation
  5. cell death
  6. cell recruitment
  7. smooth muscle cell proliferation - repair and remodelling
  8. collagen deposition
  9. formation of fibrin plug
  10. fibrin plug weakens so more likely to cause plaque rupture
  11. plaque rupture causes subendothelium to be exposed
  12. activates platelets and coagulation cascade causing thrombus formation
  13. fibrin clot can cause occlusion of artery
  14. calcification of arteries - more likely to rupture
  15. narrowing of arteries
8
Q

what is the end result of atherosclerosis formation?

A
occlusion of arteries causing:
MI
Stroke
Critical leg ischaemia
Cardiovascular death
9
Q

what is the tunica intima?

A

innermost layer of artery,

where LDL is deposited in artery

10
Q

what are the different types of angina?

A

stable

unstable

11
Q

how to treat stable angina?

A

GTN spray
aspirin
beta blocker/ calcium channel blocker
long acting nitrates

12
Q

what does GTN spray do?

A

dilates arteries

13
Q

where is LDL deposited?

A

tunica intima

14
Q

what does aspirin do?

A

prevents platelet aggregation

15
Q

what happens in stable angina?

A

there is not complete occlusion of artery/ not rupture, just narrowing.

16
Q

how to treat coronary thrombosis/ STEMI?

A

aspirin - 300mg loading dose
P2Y12 inhibitor - 600mg clopidogrel
unfractionated heparin in cath lab
PCI

17
Q

what is PCI?

A

percutaneous coronary intervention

18
Q

what is a pack year?

A

1 pack year = 20 cigarettes a day for a year, 20 in a pack

19
Q

what is T wave inversion a sign of?

A

myocardial ischaemia - NSTEMI

20
Q

difference between treating NSTEMI and unstable angina?

A

there is no difference

21
Q

how to detect an MI?

A

troponin T and I most sensitive

22
Q

what does creatinine kinase MB show?

A

re-infarction

23
Q

symptoms and signs of unstable plaque but without complete occlusion

A

chest pain intermittently but at rest
reduced exercise tolerance
associated ECG changes - T wave inversion

24
Q

how to treat NSTEMI

A
aspirin - 300mg loading dose
P2Y12 inhibitor - clopidogrel 600mg
unfractionated heparin (IV) in cath lab
anticoagulant - low molecular weight heparin until PCI
PCI ASAP but not emergency
25
Q

what is the difference between NSTEMI, STEMI, coronary thrombosis and unstable angina?

A

NSTEMI and STEMI - presentation of ECG

coronary thrombosis and unstable angina = how much occlusion there is

26
Q

how to treat unstable angina?

A
aspirin - 300mg loading dose
P2Y12 inhibitor - clopidogrel 600mg
unfractionated heparin (IV) in cath lab
anticoagulant - low molecular weight heparin until PCI
PCI ASAP but not emergency
27
Q

antiplatelet agents

A

glycoprotein IIb/IIIa inhibitors
e.g. aciximab
tirofiban
eptifibatide

28
Q

what do glycoprotein IIb/IIIa inhibitors do?

A

block integrin receptor for fibrinogen and block final platelet aggregation pathway by inhibiting fibrinogen bridges

29
Q

when are glycoprotein IIb/IIIa inhibitors used?

A

used if patient is going for PCI - just beforehand

30
Q

how can we regress or stabilise coronary plaques?

A

reduce vulnerability of plaque

risk factor management

31
Q

risk factor management

A

lower cholesterol with statins
control BP
quit smoking
other lifestyle factors - exercise, alcohol
reduce vulnerability of blood to thrombosis

32
Q

how to reduce the vulnerability of blood to thrombosis?

A

antithrombotic drugs - aspirin for life
clopidogrel or similar for 1 year following the event
need to compare bleeding risks for other agents used

33
Q

Post NSTEMI/ STEMI treatment

A
statins  - atorvastatin
antiplatelet - clopidogrel
beta blocker - bisoprolol
ACE inhibitor - ramipril
remember GI protection as these drugs cause GI bleeding - lansoprazole
34
Q

what do statins do after STEMI/ NSTEMI?

A

stabilise plaque

35
Q

what do antiplatelets do after STEMI/ NSTEMI?

A

maintain stent patency

36
Q

coronary stent

A

drug eluting stents
prevent proliferation of epithelium and reduce risk of restenosis but increases risk of stent thrombosis which is why anti-platelets are needed

37
Q

stent thrombosis

A

iatrogenic acute coronary syndrome

all stented coronaries are vulnerable

38
Q

how to prevent stent thrombosis?

A

good technique
anti-platelet drugs
90 times more likely if anti-platelets stopped early