Atherosclerosis and Valvular Heart Disease

Question 1

What is atherosclerosis?

Answer 1

Build up of hardened plaque in the intima of the artery via inflammation

Question 2

What complications does atherosclerotic plaque cause?

Answer 2

1) Gangrene
2) Heart attack
3) Stroke

Question 3

What are the 5 constituents of atherosclerotic plaque?

Answer 3

1) Lipid Core
2) Necrotic Debris
3) Connective Tissue
4) Fibrous Cap
5) Lymphocytes

Question 4

What are the main risk factors of atherosclerosis?

Answer 4

1) Smoking
2) Hypertension
3) High LDL’s level
4) Family History
5) Increasing Age
6) Obesity
7) Diabetes

Question 5

Which arteries usually contain atheromatous plaques and which histological layer is thinned by it?

Answer 5

Coronary and Peripheral Arteries

Tunica Media

Question 6

What causes chemoattractant release and what functions are carried out by chemoattractants?

Answer 6

Release: Stimulus e.g. Endothelial Cell Injury
Function: Signal to leukocytes, L accumulate and migrate to vessel wall, cytokine release e.g. I-L 1, I-L 6 causing inflammation

Question 7

What are the main steps of leukocyte recruitment?

Answer 7

1) Capture
2) Rolling
3) Slow rolling
4) Adhesion
5) Trans-migration

Question 8

What are the 5 progressive stages of atherosclerosis?

Answer 8

1) Fatty streaks
2) Intermediate lesions
3) Fibrous plaques
4) Plaque rupture
5) Plaque erosion

Question 9

What are the fatty streaks formed from?

Answer 9

Foam cells and T-lymphocytes, fatty streaks in 10 years or above

Question 10

What are the constituents of intermediate lesions?

Answer 10

Foam Cells, SMC, T Lymphocytes, Platelet adhesion and EC lipid pools

Question 11

What is the main composition of fibrous plaques?

Answer 11

1) Fibrous cap overlies lipid core and necrotic debris
- SMC, macrophages, Foam Cells, T Lymphocytes
- Impede blood flow and prone to rupture

Question 12

What is the reasoning for plaque rupture?

Answer 12

Fibrous plaques constantly grow and recede, so cap has to be resorbed and redeposited to maintain balance
- Balance shifted to inflammatory conditions then cap weakened and plaque ruptured, thrombus formation and vessel occlusion

Question 13

What is the treatment, limitation of treatment and avoidance of limitation of atherosclerosis?

Answer 13

T: Percutaneous Coronary Intervention
L: Restenosis
A: Drug eluting stents, anti-proliferative and drugs inhibiting healing

Question 14

What is atherogenesis?

Answer 14

Development of atherosclerotic plaque

Question 15

What are 4 main valvular heart diseases?

Answer 15

1) Aortic Stenosis
2) Mitral Regurgitation
3) Mitral Stenosis
4) Aortic Regurgitation

Question 16

Outline aortic stenosis

Answer 16

• Aortic orifice is restricted so LV can’t properly eject blood when in systole
• Pressure overload

Question 17

What is the aetiology and pathophysiology of AS?

Answer 17

A: Congenital Bicuspid valve or Acquired
PP: Aortic orifice restricted e.g. by Ca2+ deposits so pressure gradient between Aorta and LV
- Comp. Hypertrophy maintains LV function initially but exhausted overtime –> LV failure

Question 18

What are 3 signs and symptoms of Aortic stenosis?

Answer 18

Symp: Exertional Syncope, Angina, Exertional Dyspnoea
Signs: Slow ^ carotid pulse and V pulse amplitude, soft/absent heart, ejection systolic murmur (<>)

Question 19

What are the investigations and management for AS?

Answer 19

I: Echocardiography
M: Good dental hygiene, IE prophylaxis and Aortic valve replacement
AVR if symptomatic, decreasing ejection fraction or undergoing CABG

Question 20

Outline mitral regurgitation

Answer 20

Backflow of blood from LV –> LA during systole (Volume Overload)

Question 21

What is the aetiology and pathophysiology of mitral regurgitation?

Answer 21

A: Myxomatous degeneration, Ischaemic mitral regurgitation, Rheumatic HD, IE
PP: LV vol overload, so LA enlarged and LVH and increased contractility to compensate
- Progressive LV volume overload, dilatation and progressive Heart Failure

Question 22

What are the symptoms and signs of mitral regurgitation?

Answer 22

Signs: Pansystolic Murmur, Soft 1st heart sound, 3rd heart sound (Murmur intensity correlates with disease severity)
Symptoms: Dyspnoea on exertion and HF

Question 23

What investigations and management would be conducted in MR?

Answer 23

Inv: ECG, CXR and Echo (LA/LV size/function)
Man: Rate control for AF e.g. BB, anticoagulation, diuretics for fluid overload and IE prophylaxis

Question 24

Outline aortic regurgitation?

Answer 24

Regurgitant aortic valve means blood leaks back into LV during diastole as aortic cusps ineffective

Question 25

What is the aetiology and PP of AR?

Answer 25

A: Bicuspid aortic valve, Rheumatic and IE
PP: Pressure and Volume overload, compensatory mechanisms –> LV dilatation, LVH, Progressive dilatation –> HF

Question 26

What are the signs and symptoms of AR?

Answer 26

Signs: Wide pulse pressure, diastolic blowing murmur and systolic ejection murmur
Symptoms: Dyspnoea on exertion, Orthopnoea, Palpitations and Paroxysmal nocturnal dyspnoea

Question 27

How would you investigate and manage aortic regurgitation?

Answer 27

I: CXR and echocardiogram
M: IE prophylaxis, vasodilators, regular echo’s monitor progression with surgery if symptomatic

Question 28

Outline mitral stenosis?

Answer 28

Obstruction to LV inflow that prevents proper filling when in diastole

Question 29

What’s the aetiology and PP of MS?

Answer 29

A: RHD, IE and Calcification
PP: a) LA dilation –> Pulmonary congestion
b) Increased trans-mitral pressure –> LA enlargement and AF
c) Pulmonary venous HT causes RHF symptoms

Question 30

What are the signs and symptoms of MS?

Answer 30

Signs: RHF, Cheek pink patches from VC, low pitched diastolic murmur, loud opening snap 1st heart sound and “a” wave in jugular venous pulsations
Symptoms: Dyspnoea, Haemoptysis and RHF symptoms

Question 31

How is MS investigated and managed?

Answer 31

I: ECG, CXR and Echo (Gold Standard)
M: If AF -> BB/CCB, AC -> from AF
Balloon valvuloplasty or valve replacement –> IE prophylaxis