Pathology of ischaemic heart disease and hypertension

Question 1

How many men die of heart die of heart disease?

Answer 1

Around 30%

Question 2

Laminar flow

Answer 2

Away to avoid clotting
Cells go down centre of artery
-endothelial cells are like Teflon coat so cells don’t tend to stick to them
-if endothelial cells flap up, reveals collagen cells and platelets love collagen and stick to it and release signals for other platelets to stick to them and aggregation occurs
Fibrinogen –> fibrin –> clot

Question 3

Thrombosis triangle - Virchow’s triad

Answer 3

Change in vessel wall
Change in blood flow
Change in blood constituents

Question 4

Causes of ischaemic heart disease

Answer 4

Myocardial hypertrophy
Small vessel disease
Atherosclerosis
-these overlap

Question 5

Thrombosis causes

Answer 5

Heart attacks

AND?

Question 6

Ischaemia

Answer 6

a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive)

Question 7

Atherosclerosis

-porridge + stiffening

Answer 7

A disease in which plaque (atheroma?) builds up inside your arteries

Question 8

Risk factors for athersclerosis

Answer 8

Social deprivation
Men more than women
Cigarette smoking
Hypertension
Diabetes (if poorly controlled)
Hyperlipidaemia

Question 9

Cigarette smoking as a risk factor

Answer 9

Rubbish diffuses into blood and causes endothelial cell damage

Question 10

Left ventricular hypertrophy

Answer 10

Too much heart muscle
Will have same amount of blood going into it so less flow through it
Can be huge

Question 11

What is deposited in plaque

Answer 11

Continuous little areas of damage to the endothelial cells and thrombosis forms on top
High BP causes shearing of endothelial cells - could have effect
Plaque made up of fat, cholesterol, calcium, and other substances found in the blood
-over time, plaque hardens and narrows your arteries

Question 12

Bleeding within plaque

Answer 12

Not very stable
New BVs grow into them but not very stable
Bleeding within it causes expansion / growth

Question 13

Atherosclerosis causes

Answer 13

Chest pains on exercise
MI
-but very slow process over many years

Question 14

What can cause left ventricular hypertrophy

Answer 14

Stenosis of aortic valve

Question 15

Small vessel changes

Answer 15

At arteriolar level
Inappropriate vasoconstriction
–< production of nitric oxide
– > destruction of nitric oxide

Question 16

What does ischaemic heart disease look like?

Answer 16

Regional transmural myocardial infarction
Subendocardial myocardial infarction
Chronic ischaemia

Question 17

Regional transmural myocardial

infarction

Answer 17

Acute occluding event in one of the three
main coronary arteries
Lack of collateral circulation from the other
vessels
Patch of dead heart muscle in one area of the heart the whole thickness of the wall because 1 artery is blocked off

Question 18

Subendocardial myocardial

infarction

Answer 18

Severe coronary artery atherosclerosis in
all three main coronary arteries
Some sudden reduction in blood flow e.g.
hypotension during an operative procedure
Just beneath endocardium
Or around left ventricle but not all the way through

Question 19

Chronic ischaemia

Answer 19

‘Fixed’ atherosclerotic lesions
Angina
Myocardial fibrosis
Hibernating myocardium
Stunned myocardium

Question 20

Complications of myocardial infarction

Answer 20

Sudden death
Arrhythmias
Cardiac failure
Mitral incompetence
Pericarditis
Cardiac rupture
Mural thrombosis
Ventricular aneurysm
Pulmonary emboli

Question 21

Sudden death

Answer 21

Arrhythmias such as ventricular fibrillation
-not really pumping any blood round
Rational for acute coronary care services

Question 22

Cardiac failure

Answer 22

Arrhythmias
-complete heart blocks
Loss of myocardium and so reduced pump
function

Question 23

Mitral incompetence

Answer 23

Rupture or necrosis of papillary muscles

Pan systolic murmur

Question 24

Cardiac rupture

Answer 24

Weakening of wall due to muscle necrosis
and acute inflammation
3-7 days after infarction
Rupture into pericardial sac
Rupture of interventricular septum

Question 25

Mural thrombosis

Answer 25

Thrombosis on the abnormal endothelial
surface following infarction
7-14 days after infarction
Embolisation to any arterial site

Question 26

Ventricular aneurysm

Answer 26

Stretching of newly-formed collagenous
scar tissue
4 weeks or more after infraction
May be associated with cardiac failure
May contain thrombus

Question 27

Clinical importance of hypertension

Answer 27

Commonest cause of heart failure in most
countries
Major risk factor for atherosclerosis
Major risk factor for cerebral haemorrhage

Question 28

Hypertension

Answer 28

High blood pressure

Question 29

One year survival failure of heart failure

Answer 29

Around 60%

Question 30

Measuring blood p

Answer 30

We measure a smoothed out version of what happens in the heart on the arm
Goes down in the night

Question 31

What is high blood pressure (TABLE)

Answer 31

A high systolic (130 and over) or diastolic (80 and over) can count as high blood pressure

Question 32

Classification of high blood presure

Answer 32

Primary
– no definitely identified cause
Secondary
– identifiable cause

Question 33

Primary hypertension

Answer 33

Adrenalin
Sodium control
Renin angiotensin aldosterone
-these overlap
-poorly understood

Question 34

Secondary hypertension

Answer 34

Renal
– renin dependent
– salt and water overload
Endocrine
– Cushing’s, Conn’s, phaeochromocytoma
Coarctation of aorta
Drug therapy
– corticosteroids, NSAIDs

Question 35

Clinicopathological classification

Answer 35

Benign
– long asymptomatic period
– increased frequency of complications later
Malignant
– markedly raised diastolic pressure
– symptomatic
– rapidly fatal if untreated

Question 36

Effects of hypertension

Answer 36

• accelerated atherosclerosis
• sclerosis of smaller vessels
• microaneurysms and haemorrhages
• heart failure
• kidney failure
• cerebral haemorrhages = ‘strokes’