Flashcards in Thrombosis Deck (13)
What can a bad clot lead to ?
What characteristic features are seem in arterial thrombosis?
fatty streaks in arteries - we will already have some
narrowing of the lumen => plaque rupture
both obesity and smoking exacerbate this condition
How many deaths due to VTE occur in Europe?
about 543 454 = exceeds combined deaths due to AIDS, breast cancer, prostate cancer, transport accidents
What is the cascade of events with a DVT?
DVT = source clot that tends to occur in lower limb but can also occur in upper limb
=> can lead to a PE which can lead to death/ pulmonary hypertension and then onto death
=> also causes deep vein insufficiency => post-thrombotic syndrome => venous ulcers
What is the crude mortality in the elderly of DVT?
15-20% within 3 months of diagnosis
What is PTS?
Post-thrombotic syndrome= continuing burden
- after symptomatic DVT
- overall frequency is 20-50%
- severe PTS occurs in 5-10% of patients
pain, swelling and ulceration of the legs
What is virchow's triad?
- alterations in normal blood flow (stasis) - can be due to intrinsic pressure
- injuries to the vascular endothelium
- alterations in the constitution of the blood (hyper coagulability)
How much more likely is VT in pregnancy and why?
10x more likely
- state of hyper coagulability = increased clotting factors, reduced fibrinolysis, increased platelet adhesiveness = in preparation for birth
Venous stasis resulting from pressure of the gravid uterus on inferior vena cava and decreased venous tone
- may compress R iliac vein therefore always roll pregnancy women onto L side
Other than pregnancy when else is the risk of DVT increased?
when in hospital - 100 fold increased risk - give heparin (blood thinning)
- every patient is given a leaflet on DVT pre-admission clinic
How does protein C activation occur and what does it do?
stops clot propagating but you need an intact endothelium
- protein c is activated by thrombin-thrombomodulin complex
- activation protein c binds free protein s which then inactivates activated FV and FVIII
Which FV is slight resistance to activated protein c?
Which SNPs predict risk of VTE recurrence?
F5 FV leiden = non-penetrant
F2 20210 G>A
FGG 10034 C>T
Low GRS (<1risk allele) = 9.4% recurrence at 6 years
high GRS (>5 risk alleles) = 20.3% recurrence at 6 years