Hypertension

Question 1

Certain genetic loci have been associated with hypertension risk

Answer 1

Variations in the genes encoding the renin-angiotensin system.

Particularly mutations in the genes of the angiotensinogen and angiotensin receptor locus

Question 2

Risk factors in hypertension

Answer 2

Stress
Obesity/sedentary lifestyle
Smoking
High salt intake

Question 3

How common is secondary hypertension?

Answer 3

Rare - 5%, due to:
Adrenocortical hyperfunction (Cushing’s etc)
Exogenous hormones (glucocorticoids, etc)
Phaeochromocytoma
Renal artery stenosis

Question 4

Hyaline arteriosclerosis

Answer 4

Arteriolar wall is thickened due to increased protein deposition narrowing the lumen
This is due to plasma proteins leaking across injured endothelial cells and increased smooth muscle matrix deposition in response to raised haemodynamic stress

Question 5

Hyaline arteriosclerosis mainly affects

Answer 5

Retina
Kidney
Heart

Question 6

Hyaline arteriosclerosis also occurs as part of another condition

Answer 6

Diabetic microangiopathy

Question 7

The major complications of hypertension are

Answer 7

Cardiac hypertrophy and heart failure
Multi-infarct dementia (Lacunar infarcts)
Aortic dissection
Renal failure
Major risk factor for atherosclerosis

Question 8

Accelerated (Malignant) hypertension

Answer 8

A rapid rising blood pressure that if untreated leads to death with two years
High pressure causes hyperplastic (onion skinning) arteriosclerosis which obliterates the lumen
Mainly affects the kidney (AKI) or the brain (cerebral haemorrhage)

Question 9

Hyperplastic arteriosclerosis (Onion-skinning)

Answer 9

Occurs in accelerated hypertension
High pressure causes intimal hyperplasia and necrosis.
Produces concentric laminations of VSMCs with thickened and duplicated basement membranes
Accompanied by fibrinoid deposits and vessel wall death (necrotising arteriolitis)

Question 10

Which organ are most effected by necrotising arteriolitis?

Answer 10

The kidney

Question 11

The difference between accelerated and malignant hypertension

Answer 11

Accelerated - Hypertensive urgency, severe hypertension associated with grade 2/3 KWB retinopathy
Malignant - Hypertensive crisis, severe hypertension associated with grade 4 KWB retinopathy with papilloedema +- impending or progressive end organ damage - 90% untreated 1year mortality

Question 12

End organ damage in malignant hypertension

Answer 12

Hypertensive encephalopathy/Intracerebral haemorrhage/acute thrombotic stroke
IHD/ACS/LVF with pulmonary oedema/Aortic dissection
Renal impairment
Eclampsia

Question 13

Causes of malignant hypertension

Answer 13

Majority chronic essential hypertension with rapid rise, sometimes no reason, often due to discontinuation of medications
Also - Renal/renovascular disease, SLE, Cushing’s

Question 14

The majority of hypertension is

Answer 14

Essential (idiopathic) hypertension - 95%

This is a multifactorial disease with multiple genetic and environmental factors feeding into it

Question 15

Hypertensive encephalopathy

Answer 15

Caused by cerebral oedema and haemorrhage after failure of auto regulation in the context of hypertension
Causes severe headache, nausea, vomiting, confusion, visual disturbances, nystagmus, seizures and focal neurological signs

Question 16

Treating severe hypertension

Answer 16

If no sign of end organ damage then can be treated in high intensity out patient basis
If evidence of end organ damage then ITU admission required
Arterial line to monitor BP and rapid gradual reduction in BP
Reversible if treated but can be fatal

Question 17

BP should not be lowered too rapidly in severe hypertension because

Answer 17

Rapid reduction below the autoregulatory range gives a risk of end organ ischaemia
Aim to reduce BP by 20% in the first hour/to 160/100 in first 6hrs
IV infusion of short acting titratable anti-hypertensive

Question 18

Agents used to acutely treat severe hypertension

Answer 18

Sodium nitroprusside - long term use can cause cyanide poisoning
Glyceryl trinitrate, Labatelol, Hydralazine
Don’t use sublingual nifedipine - dangerous

Question 19

Drugs used for the initial treatment of hypertension

Answer 19

A (55yrs or black) –> A + C –> A + C + D —> resistant hypertension A + C + D + B
A - ACEi C - calcium channel antagonists
B - Beta-blockers D - thiazide diuretics

Question 20

Stages of HTN

Answer 20

stage 1 –> 140/90> & ambulatory/home average BP >135/85
Stage 2 –> 160/100> & ambulatory/home average BP 150/95>
stage 3/severe –> clinical systolic >180 or diastolic >110

Question 21

Postural hypotension

Answer 21

Is a drop in systolic BP of 20> when standing with symptoms

Question 22

Treatment Step 1

Answer 22

ACEi (enalapril, etc) if 55 or black
ARB (Lorsartan, Candasartan) if ACE not tolerated, if neither then B-blocker
Atypical Thiazide (chlortadidone, indapamide) if CCB not tolerated

Question 23

Treatment step 2

Answer 23

Add CCB to ACEi/ARB or thiazide if intolerant of CCB

Add ACEi/ARB to CCB or thiazide (ARB if black)

Question 24

Treatment step 3

Answer 24

ACEi/ARB + CCB + Thiazide

Question 25

Resistant HTN

Answer 25

remains above 140/90 after step 3 treatment. If renal function is good add spirolactone (K+<4.5) or increase thiazide

Question 26

ACEi contraindications

Answer 26

Dont use for pts with previous angiooedema/ hypersensitivity or with renal artery stenosis
Caution should be taken with pts with Aortic or pulmonary stenosis/outflow obstruction, dehydrated/hypovolaemia or haemodialysis
Sig. pregnancy risk in 2nd or 3rd trimester and shouldnt be taken by women at risk of pregnancy
Risk of hyperkalaemia, cough and angioedema

Question 27

Asthmatics

Answer 27

Careful with ACEis and B-blockers, as can trigger attacks

Question 28

CCB Contraindications

Answer 28

Can cause flushing, headache, hypotension and oedema
Should not be given to pts at risk or bradycardia, conduction defects or heart failure.
Should not combine with a B-blockers

Question 29

ARB contraindications

Answer 29

Contraindicated in pregnancy & pts with bilateral renal artery stenosis

Question 30

Thiazide diuretic contraindications

Answer 30

Increase triglycerides, cholesterol, glucose, LDL
and decreases volume, sodium, potassium.
decreased efficacy NSAIDs, corticosteroids increasehypokalaemia, B-blockers potentiate hyperglyaemia/hyperlipidaemia
Risk of gout

Question 31

Gestational Hypertension

Answer 31

Treat with MethylDOPA