Atherosclerosis and Valvular Heart Disease Flashcards
What is atherosclerosis?
Build up of hardened plaque in the intima of the artery via inflammation
What complications does atherosclerotic plaque cause?
1) Gangrene
2) Heart attack
3) Stroke
What are the 5 constituents of atherosclerotic plaque?
1) Lipid Core
2) Necrotic Debris
3) Connective Tissue
4) Fibrous Cap
5) Lymphocytes
What are the main risk factors of atherosclerosis?
1) Smoking
2) Hypertension
3) High LDL’s level
4) Family History
5) Increasing Age
6) Obesity
7) Diabetes
Which arteries usually contain atheromatous plaques and which histological layer is thinned by it?
Coronary and Peripheral Arteries
Tunica Media
What causes chemoattractant release and what functions are carried out by chemoattractants?
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
What are the main steps of leukocyte recruitment?
1) Capture
2) Rolling
3) Slow rolling
4) Adhesion
5) Trans-migration
What are the 5 progressive stages of atherosclerosis?
1) Fatty streaks
2) Intermediate lesions
3) Fibrous plaques
4) Plaque rupture
5) Plaque erosion
What are the fatty streaks formed from?
Foam cells and T-lymphocytes, fatty streaks in 10 years or above
What are the constituents of intermediate lesions?
Foam Cells, SMC, T Lymphocytes, Platelet adhesion and EC lipid pools
What is the main composition of fibrous plaques?
1) Fibrous cap overlies lipid core and necrotic debris
- SMC, macrophages, Foam Cells, T Lymphocytes
- Impede blood flow and prone to rupture
What is the reasoning for plaque rupture?
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
What is the treatment, limitation of treatment and avoidance of limitation of atherosclerosis?
T: Percutaneous Coronary Intervention
L: Restenosis
A: Drug eluting stents, anti-proliferative and drugs inhibiting healing
What is atherogenesis?
Development of atherosclerotic plaque
What are 4 main valvular heart diseases?
1) Aortic Stenosis
2) Mitral Regurgitation
3) Mitral Stenosis
4) Aortic Regurgitation
Outline aortic stenosis
- Aortic orifice is restricted so LV can’t properly eject blood when in systole
- Pressure overload
What is the aetiology and pathophysiology of AS?
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
What are 3 signs and symptoms of Aortic stenosis?
Symp: Exertional Syncope, Angina, Exertional Dyspnoea
Signs: Slow ^ carotid pulse and V pulse amplitude, soft/absent heart, ejection systolic murmur (<>)
What are the investigations and management for AS?
I: Echocardiography
M: Good dental hygiene, IE prophylaxis and Aortic valve replacement
AVR if symptomatic, decreasing ejection fraction or undergoing CABG
Outline mitral regurgitation
Backflow of blood from LV –> LA during systole (Volume Overload)
What is the aetiology and pathophysiology of mitral regurgitation?
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
What are the symptoms and signs of mitral regurgitation?
Signs: Pansystolic Murmur, Soft 1st heart sound, 3rd heart sound (Murmur intensity correlates with disease severity)
Symptoms: Dyspnoea on exertion and HF
What investigations and management would be conducted in MR?
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
Outline aortic regurgitation?
Regurgitant aortic valve means blood leaks back into LV during diastole as aortic cusps ineffective
