Hypertension- Pathology

Question 1

What is hypertension?

Answer 1

Level of Sustained arterial pressure is higher than normal .

Question 2

What is the minimum BP value for hypertension?

Answer 2

BP of or higher than 140/90mmHg.

Question 3

Why’s it important to take multiple readings of BP before confirming?

Answer 3

BP of individuals vary throughout the day.

Question 4

What diseases can hypertension be a risk factor for?

Answer 4

• Atheroma - Cerebral haemorrhage - Renal failure - Sudden cardiac death

Question 5

What is the epidemiology of hypertension?

Answer 5

• Varies between countries. - Higher in south asian groups - Increase with age.

Question 6

What are the classifications of Hypertension?

Answer 6

1. Aetiology (cause) - Primary: unknown cause. 90%. Genetic factors, salt intake. - Secondary: caused by another disease. 2. Consequences - Benign - Malignant (accelerated)

Question 7

What are the two effects of the RAAS system on the body?

Answer 7

• Vasoconstriction - Salt/water retention

Question 8

What is salt sensitive hypertension?

Answer 8

Increase in salt intake increases BP. Can sometimes be seen in primary hypertension. Can also be associated with renal disease hypertension.

Question 9

What are some underlying diseases seen in 2ndary hypertension?

Answer 9

1. Renal disease 2. Endocrine disease 3. Aortic disease 4. Renal artery stenosis 5. Drug therapy.

Question 10

What are some renal causes of hypertension? How does it cause hypertension?

Answer 10

Renal artery stenosis Acute/chronic glomerulonephritis chronic pyelonephritis cystic disease interstitial nephritis Reduces blood flow to kidneys–>Excess renin release–> Salt/water overload–> Hypertension.

Question 11

What are some endocrine causes of hypertension?

Answer 11

1. Adrenal gland hyperfunction/tumours 2. Conn’s syndrome- excess Aldosterone 3. Cushing’s syndrome- excess Corticosteroid 4. Pheochromocytoma- excess noradrenaline

Question 12

What are some other causes of hypertension? (aorta)

Answer 12

Coarctation of the aorta- Congenital narrowing of segments of aorta. Drugs- corticosteroids.

Question 13

What is benign hypertension?

Answer 13

Something that can cause serious life threatening morbidity. Asymptomatic, incidental finding, often on health checks.

Question 14

What is Left ventricular hypertrophy?

Answer 14

Enlargement of the cardiac myocytes in the left ventricle, in response to high blood pressure.

1. High BP increases the the after-load in the left ventricle
2. myocyte hypertrophy,
3. Collagen + fibroblasts deposition–> interstitial fibrosis.
4. Result- Reduced compliance and diastolic dysfunction.

Question 15

What disease can LVH cause?

Answer 15

1. Sudden cardiac death- arrhythmias and poor perfusion. 2. Cardiac failure- can affect other diseases. Eg stroke

Question 16

What is an aortic dissection?

Answer 16

Tear in the wall of the aorta that causes blood to flow into and dissect the inner and middle layers of the aortic wall.

Question 17

What is a berry aneurysm?

Answer 17

Weakness in the wall of a cerebral artery causes dilation (ballooning) of that artery.

Question 18

What are some microvascular injuries that can be caused by hypertension?

Answer 18

Blood vessel wall changes- small arteries and arterioles: 1. Retina and renal 2. Thickening of media (smooth muscle) 3. Hyaline arteriosclerosis- leakage of plasma proteins into vessel

Question 19

What is malignant hypertension? What does the Diastolic value have to be for it to be malignant?

Answer 19

Serious life threatening condition. Diastolic BP- Has to be over 130 Can arise from benign, primary or secondary Needs immediate treatment to avoid death.

Question 20

What are some of the deadly effects of Malignant hypertension?

Answer 20

1. cerebral oedema, seen as papilloedema (swelling of optic disc) 2. Acute renal failure 3. Acute heart failure 4. Headaches & cerebral haemorrhages 5. Blood vessels show: - Fibrinoid necrosis - endarteritis proliferans of their walls.

Question 21

What happens in pregnancy associated hypertension?

Answer 21

Increased maternal and foetal mobirdity and mortality. Pre-Eclampsia- Pregnancy induced Hypertension, fluid retention and proteinuria. Usually resolves following birth. Eclampsia- medical emergency.