Pathophysiology of thrombosis and embolism 2 Flashcards
What can cause air embolism?
Head and neck wounds
Surgery
CV lines
What can cause gas embolism?
Decompression sickness - N2 forms as bubbles which lodge in capillaries
What are the types of embolus?
Thromboembolus
Fat embolus
Air embolus
Tumour embolus - spread of tumour
Amniotic fluid - cause of collapse in childbirth
Septic material e.g infective endocarditis
Trophoblast - pregnant women -lungs
Bone marrow - fractures from like e,g CPR
Foreign bodies e.g intravascular cannulae tips, sutures etc
What is rheumatic fever?
Disease of disordered immunity
What are the symptoms of rheumatic fever?
Inflammatory changes in the heart and joints, sometimes neurological symptoms
What countries are rheumatic fever common?
India, middle east and central africa.
It is however now rare in Europe and north america.
What age does rheumatic fever commonly affect?
Ages 5-15 years
More common in boys than girls
What is the presenting feature of rheumatic fever?
- Flitting (painful) polyarthritis of large joints like wrists, elbows, knees and ankles.
- Skin rashes and fever
What are the symptoms of rheumatic fever in the acute phase?
Pancarditis and heart murmurs are common.
Why do most patient have a sore throat with rheumatic fever?
Usually due to group A beta-haemolytic streptococcal infection
Why would may damage to heart tissue caused by in rheumatic fever?
Combination of antibody-mediated and T cell-mediated reactions.
What is aschoff body?
Focus of chronic inflammatory cells, necrosis and activated macrophages (anitschkow cells)
Where may aschoff body be seen?
In the heart in acute rheumatic fever
What does pathological problems of valvular heart disease result from?
Valvular stenosis
Valvular incompetence/regurgitation
Vegetations
What happens in valvular stenosis
Valve is thickened/calcified and obstructs normal blood flow into chamber/vessel
What causes valvular incompetence/regurgitation?
Valves loses normal function and fails to prevent reflux of blood after contraction of cardiac chamber.
What causes vegetations?
Infective or thrombotic nodules develop on valve leaflets impairing normal valve mobility; may embolise
What can pancarditis in acute rheumatic fever progress to over time?
To chronic rheumatic heart disease, mainly manifesting as valvular abnormalities
What does inflammation of the endocardium and left sided valves result in?
Fibroid necrosis of the valve cusps/chordae tendineae, over which form small vegetations
What is rheumatic heart disease virtually the only cause of?
Mitral stenosis
What is mitral regurgitation most commonly due to?
Ischaemic heart disease
What does rheumatic heart disease potentially still cause?
Aortic regurgitation/incompetence.
What valves are rarely and infrequently involved in rheumatic heart disease?
Tricuspid and pulmonary valve
What does rheumatic heart disease rarely cause?
Aortic stenosis
What is rheumatic heart disease principally characterised by?
Deforming fibrotic valvular disease, particularly involving the mitral valve.
