Hypertension and Hyperlipidaemia Flashcards
Stage 1 Hypertension
clinic blood pressure is higher than 140/90 mmHg AND ambulatory BP is 135/85mmHg average
Stage 2 Hypertension
clinic BP is higher than 160/100mmHg AND ambulatory BP is 150/95mmHg or higher
Stage 3 hypertension
clinic systolic is 180mmHg or higher OR clinic diastolic is 110mmHg or higher
Potentially affected organs in hypertension (5)
Brain, Eyes, Kidneys, Heart, Arterial Tree
Potential effect of hypertension on the brain
stroke
Potential effect of hypertension on the eyes
Impaired vision
Potential effect of hypertension on the kidneys
narrowing and thickening of renal arteries leading to kidney damage
Potential effect of hypertension on the heart
MI, congestive heart failure
Potential effect of hypertension on the arteries
atherosclerosis
aortic aneurysm
Populations more likely to have high BP
African-americans
deprived areas
Structural changes that occur in the arteries due to hypertension
internal elastic lamina thickening
smooth muscle hypertrophy
fibrosis
all of these reduce the lumen and increase shear stress on the intima
artherosclerosis causes a(n) _______ in total peripheral resistance
increase
types of hypertension (2)
primary (essential) and secondary
Most common type of hypertension
primary (essential) 90-95% of cases
Good form of cholesterol
HDL
Bad form of cholesterol
LDL
4 major types of lipoproteins
HDL, LDL, VLDL, Chylomicrons
Lipid are soluble in water - True or false
false
What can lipids be used for? (3)
energy, hormones, signalling molecules
The hydrophobic core in lipoproteins contains?
esterified cholesterol and triglycerides
The hydrophillic coat of lipoproteins contains?
amphipathic cholesterol, phospholipids and one or more apoproteins
Cardiovascular disease is associated with which types of lipids?
elevated LDL, high triglycerides, low HDL
where does the majority of cholesterol come from?
from the bile, only 25% comes from the diet
The majority of LDL is cleared by…
the liver
Rate limiting enzyme in de novo cholesterol synthesis
HMG CoA reductase
Released cholesterol causes: (3)
inhibition of HMG coA reductase; down regulation of LDL receptor express; storage of cholesterol as an ester
Clearance of LDL is dependent upon?
the LDL receptor on the liver and other tissues
Why is LDL cholesterol bad in the arteries?
it migrates into the intima and produces OXLDL which causes the migration of monocytes into the endothelium and the formation of foam cells and a fatty streak.
Why is HDL cholesterol the good cholesterol?
transports excess cholesterol back to the liver where it can be cleared from the body
Secondary dyslipidaemia is a consequence of other diseases such as…(4)
T2DM, hypothyroidism, alcoholism, liver disease
Statins act via…
inhibiting HMG CoA reductase
Examples of statins (2)
Simvastatin, atorvastatin
Where are statins not effective?
in homozygous familial hypercholesteraemia
What time of day should statins be taken?
at night
Other beneficial effects of statins?
reduce inflammation; reverse endothelial dysfunction; decrease thrombosis; stabilise atherothrombotic plaques
Where should statins be avoided?
pregnancy; rhabdomyolosis
Where are fibrates used?
in high triglycerides, also produce a modest decrease in LDL
Examples of fibrates (2)
benzofibrate
gemfibrozil
where are fibrates used as first line?
in patients with high triglycerides
Where are fibrates best avoided?
in alcoholics
Examples of drugs that inhibit cholesterol absorption (3)
cholestryamine, colestipol, celsevelam
How do drugs inhibiting cholesterol absorption act?
bile acid binding residues which binds cholesterol in the GI tract to prevent absorption
How does Ezetimibe work?
inhibits NPC1L1 transport protein in the enterocytes reducing the absorption of cholesterol - NOT FIRST LINE
Common causes of Atheroma
smoking, hypertension, hyperlipidaemia, diabetes, age, sex, genetics
4 stages of pathogenesis of Atheroma
- Primary endothelial injury; 2. Accumulation of lipids and macrophages; 3. Migration of smooth muscle cells; 4. increase in size
5 complications of atheroma
Stenosis; Thrombosis; Aneurysm formation; Arterial dissection; Embolism
What is stenosis?
a narrowing of the lumenal calliper, reduced elasticity
Stenosis may produce tissue ischamia which may be seen in the forms of?
angina, MI, cardiac failure, cardiac fibrosis, carotid artery disease (TIA, stroke), renal artery hypertension
What infarctions may a thrombus cause?
MI, cerebral, renal, intestinal
What is an aneurysm?
a abnormal and persistant dilation of an artery due to a weakness in its wall
Commonest site of aneurysm formation
abdominal aorta
Conditions associated with arterial dissection
atheroma and hypertension, trauma, coarction, marfans, pregnancy
hypertension causes…
cardiac failure, atheroma, cerebral haemorrhage, renal failure, sudden cardiac death
what is masked hypertension?
when a patient has hypertension at home, but this appears normal in the clinic
Cardiac output is affected by (3)
Heart rate, contractility, blood volume
Peripheral resistance constrictors include?
catecholamines, AngII
Peripheral resistance dilators include?
NO, prostaglandins
How might primary hypertension be defined?
hypertension with no obvious cause which is likely to be affected by genetic and lifestyle factors
Secondary hypertension due to renal disease is salt sensitive - true or false?
true
Common causes of secondary hypertension
renal disease, obstructive sleep apnoea, aldosteronism, reno-vascular disease
Renal disease causes hypertension by what mechanism??
decreased renal blood flow leads to excessive renin secretion and thus salt and water overload
Benign hypertension can be described as…
hypertension that will cause serious life threatening conditions but is often asymptomatic
Benign hypertension can lead to…
LV hypertrophy, congestive heart failure, atheromas, aneurysm rupture, aortic dissection, berry aneurysms, renal disease
Anyone diagnosed with hypertension should have which 4 tests
urine (protein), Bloods, fundi for hypertensive retinopathy, 12 lead ECG
Bloods to be checked for in hypertension
glucose, electrolytes (ACEIs), creatinine, Glomerular Filtration rate, cholesterol and fasting lipids
Spironolactone is given at which step in hypertension treatment?
step 4
Other drugs that can be given when ACEIs, CCB and thiazide like diuretics are not successful
Beta blockers, Spironolacton
Malignant hypertension is seriously life threatening - it is described as…
diastolic > 130/140mmHg
malignant hypertension can result in…
papilloedema, acute renal failure, acute heart failure, head ache, cerebral haemorrhage, fibrinoid necrosis in arteries
Gestational hypertension causes
eclampsia and an increase in maternal and foetal mortality
pre-eclampsia is diagnosed as…
hypertension and proteinuria
