Pathology of Hypertension

Question 1

what is hypertension?

Answer 1

= high blood pressure

- when the level of sustained arterial pressure is higher than expected for the age, sex and race of the individual

Question 2

what blood pressure would be classed as hypertensive?

Answer 2

blood pressure of > 140/90

Question 3

why is important to repeat a blood pressure measurement?

Answer 3

as there is normal variation in individuals at different times of the day

Question 4

what are the 2 types of hypertension?

Answer 4

1) white coat hypertension

2) stable or labile hypertension

Question 5

when does white coat hypertension arise?

Answer 5

patient feels anxiety in a medical environment causing an abnormally high blood pressure

Question 6

what does labile hypertension mean?

Answer 6

blood pressure that fluctuates abruptly & repeatedly from normal to high.
e.g. due to emotional stress.

Question 7

what can hypertension cause?

Answer 7

cardiac failure

Question 8

what 4 things is hypertension a risk factor for?

Answer 8

1) cerebral haemorrhage
2) atheroma
3) renal failure
4) sudden cardiac death

Question 9

in what type of populations is hypertension higher or lower?

Answer 9

Higher
= in black populations

Lower
= in South Pacific

Question 10

what 2 non-modifiable factors influence hypertension?

Answer 10

1) familial tendency

2) rises with age

Question 11

what 2 ways can you classify hypertension?

Answer 11

1) according to cause

2) according to consequence

Question 12

what are the 2 branches of ‘according to cause’ classification of hypertension?

Answer 12

1) primary

2) secondary

Question 13

what are the 2 branches of ‘according to consequence’ classification of hypertension?

Answer 13

1) bening

2) malignant

Question 14

what is the relationship between blood pressure, cardiac output and peripheral resistance?

Answer 14

Blood pressure = cardiac output x peripheral resistance

Question 15

what 3 things affect cardiac output?

Answer 15

1) heart rate
2) contractility
3) blood volume

Question 16

what 2 things affect peripheral resistance?

Answer 16

1) constrictors

2) dilators

Question 17

give examples of constrictors and dilators, that are part of peripheral resistance?

Answer 17

1) constrictors
e. g. angiotensin II
e. g. catecholamines

2) dilators
e. g. nitric oxide
e. g. prostaglandins

Question 18

once renin is release from the kidney, what does it combine with to form angiotensin I?

Answer 18

combines with angiotensinogen.

Question 19

what enzyme converts angiotensin I into angiotensin II?

Answer 19

ACE = angiotensin converting enzyme (lungs).

Question 20

what 2 things can angiotensin II do?

Answer 20

1) release aldosterone

2) vasoconstriction

Question 21

what does the release of aldosterone cause?

Answer 21

salt & fluid retention

Question 22

what causes primary hypertension?

Answer 22

= no obvious cause

• genetic factors (twin studies)
• salt intake
• protein intake
• renin, angiotensin system
• sympathetic activity (BP = TPR x CO)

Question 23

in salt sensitive hypertension, what does an increase in dietary salts do to the BP?

Answer 23

increases BP

Question 24

what sort of genetic factor influences salt sensitive hypertension?

Answer 24

genetic polymorphisms

Question 25

what sort of renal disease is usually salt sensitive?

Answer 25

renal disease 2y hypertension

Question 26

what are the 5 possible causes of secondary hypertension?

Answer 26

1) renal disease
2) endocrine disease
3) aortic disease
4) renal artery stenosis
5) drug therapy

Question 27

what sort of renal diseases can cause secondary hypertension?

Answer 27

• renal artery stenosis
• acute or chronic glomerulonephritis
• chronic pyelonephritis
• cystic diseases
• interstitial nephritis

Question 28

what are the consequences of renal diseases?

Answer 28

= reduced renal blood flow
= excess renin release
= salt and water overload

Question 29

what are 4 possible endocrine diseases that could cause secondary hypertension?
- what do each of these causes do?

Answer 29

1) adrenal gland hyperfunction
= tumours

2) Conn’s syndrome
= excess aldosterone

3) Cushing’s syndrome
= excess corticoid steroids

4) Phaecochromocytoma
= excess noradrenaline

Question 30

what are 2 other possible secondary causes?

Answer 30

1) coarctation of the aorta
= congenital narrowing of segments of the aorta

2) drugs
= including corticosteroids

Question 31

what are the 2 branches of causes of hypertension according to consequence?

Answer 31

1) benign hypertension

2) malignant (accelerated) hypertension

Question 32

what is benign hypertension a cause of?

Answer 32

= serous life threatening morbidity

Question 33

True or False.

Bening hypertension is asymptomatic.

Answer 33

True

Question 34

what does benign hypertension eventually cause?

Answer 34

• left ventricular hypertrophy
• congestive cardiac failure
• increases atheroma
• increases aneurysm (excessive swelling of wall of artery) rupture = aortic dissection, berry aneurysms
• renal disease

Question 35

hypertension causes left ventricular hypertrophy. what does this do to the heart?

Answer 35

1) increased LV load
2) poor perfusion
3) interstitial fibrosis
4) micro-infarcts
5) diastolic dysfunction

Question 36

what does this ventricular hypertrophy cause?

Answer 36

= sudden cardiac death
- arrhythmias & poor perfusion

= cardiac failure

Question 37

what is a sub-arachnoid haemorrhage?

Answer 37

= an uncommon type of stroke caused by bleeding on the surface of the brain

i.e. rupture of berry aneurysm

Question 38

in benign hypertension, how is the risk of MI doubled?

Answer 38

for every 10mmHg of diastolic pressure above 85

Question 39

in benign hypertension, how is the risk of stroke doubled?

Answer 39

for every 8mmHg of diastolic pressure above 85

Question 40

in microvascular injury, what is affected and in what way?

Answer 40

1) blood vessel wall changes
- small arteries & arterioles

2) retina & kidney
3) thickening of media (smooth muscle)

4) hyaline arteriosclerosis
- plasma proteins forced into vessel wall (cf ageing)

Question 41

in malignant hypertension, what is the diastolic pressure?

Answer 41

> 130/140

Question 42

what can a malignant hypertension develop from?

Answer 42

1) primary hypertension
2) secondary hypertension
3) arise de-novo

Question 43

what does malignant hypertension do the cerebrum?

Answer 43

= cerebral oedema

- seen as papilloaedema

Question 44

what else does malignant hypertension do?

Answer 44

1) acute renal failure
2) acute heart faire
3) headache and cerebral haemorrhage
4) blood vessels show fibrinoid necrosis & endarteritis proliferans of their walls

Question 45

what does pregnancy associated hypertension cause?

Answer 45

= increased maternal and fatal morbidity & mortality

Question 46

what serious thing can pregnancy associated hypertension & proteinuria cause?

Answer 46

= pre-eclampsia

- resolves following birth

Question 47

what is hypertension secondary to?

Answer 47

1) silent renal or systemic disease