Valvular Heart Disease Flashcards
What is a valve?
A device for controlling the passage of fluid allowing movement in one direction only.
When do valves stop growing?
Around 14 years old, the loose their blood supply and become fibrous flaps.
What problems can occur with the leaflets of a valve?
- calcification
- thickening
- degeneration
- infection
- prolapse
What problems can occur with the apparatus/annulus of a valve?
- annular dilatation
- annular calcification
- chordae tethering, thickening or rupture.
- regional wall motion abnormality.
Describe the structure of the aortic valve?
- 3 self-contained leaflets
- no chordae or papillary muscles
Describe the location of the aortic valve?
- Lies between LV and aorta
- In the aortic root which doesnt move.
Describe the structure of the mitral valve?
- 2 leaflets, 6 scallops
- Posterior leaflet is smaller than the anterior.
Describe the location of the mitral valve?
- between LA and LV
- held in mitral valve annulus which is part of LV so moves.
What is the prevelance of a bicuspid aortic valve?
1-2% of population.
What is the issue with bicuspid aortic valves?
Normally no issue, but in valve disease may see symptoms quicker due to already narrower orifice.
What is ‘low flow, low gradient’ ?
The idea that the narrower the orifice in aortic stenosis, the louder the murmur. BUT if there is LV dysfunction below the valve the murmur will disappear.
List symptoms of aortic stenosis?
- decreased exercise capacity
- SOB
- chest pain
- presyncope
- syncope
What effect does aortic stenosis have on the rest of the heart?
Increased LV cavity pressure causing pressure overload
Causes LV hypertrophy.
What can cause aortic regurgitation?
- degeneration, rheumatic valve disease, aortic root dilatation
- endocarditis
- systemic disease: Marfan syndrome, Ehler Danlos syndrome, Akalysing spondylitis, SLE.
Describe symptoms of aortic regurgitation?
- decreased exercise capacity
- SOB
Describe what happens in aortic regurgitation?
Blood is pushed out into the aorta, when the heart stops contracting in diastole, the valve is incompetent and blood runs back to the ventricle.
Normal blood is still coming into the LV from the LA, so get anterograde and retrograde flow.
Volume overload causes the left ventricle to dilate.
How do people get rheumatic valve disease?
Antibody cross-reaction issue as a response to streph infection such as strep throat.
How does rheumatic fever cause cardiac injury?
- recurrent inflammation
- fibrous repair and scarring.
In the mitral valve, which leaflet is more likely to have problems and why?
Anterior as it is larger and does more work.
Why is mitral stenosis declining?
As a common cause was rheumatic heart disease, so quite rare now.
What problems arise due to mitral stenosis?
- Pressure overload causing LA dilatation.
- LA dilatation can lead to arrhythmias such as AF.
- As the LA comes from the pulmonary vein, you can get pulmonary hypertension and oedema.
List the symptoms of mitral stenosis?
- SOB
- palpitations (AF)
- chest pain
- haemoptysis
- R heart failure symptoms (oedema, ascites).
Describe mitral regurgitation and the problems that arise?
- Blood flows back to the left atrium.
- Have anterograde flow from pulmonary circulation still, so get volume overload of LA, which is transferred to the LV too.
- Volume overload of both = volume dilatation of both.
- Pulmonary hypertension.
- LV systolic dysfunction.
- Can get right heart dilatation.
- AF.
List symptoms of Mitral Regurgitation?
- Oedema (due to pulmonary hypertension)
- R heart failure symptoms
- Palpitations
- SOB
Why do children have more right heart disease?
When a foetus, you don’t need your right heart as the foramen ovale is present.
Blood ‘skips’ the heart and lungs.
If there was a significant left heart problem the foetus would be non-viable.
Why do adults get more left heart disease?
- Higher systemic pressures
- Degeneration
- Hypertension
- Secondary to other disease.
Where is the tricuspid valve located?
- Lies between RA and RV valve.
Describe the structure of the tricuspid valve?
3 leaflets
Who commonly gets tricuspid valve disease and why?
IV drug users getting endocarditis.
In adulthood tricuspid valve dysfunction is usually secondary to other disease. Give an example of this.
Pulmonary hypertension causing RV dilatation, annular stretch and secondary tricuspid regurgitation.
Where is the pulmonary valve located?
Between the RV and pulmonary artery.
How many leaflets does the pulmonary valve have?
3
How do we medically treat valve disease?
- Diuretics for fluid overload.
- Control rate and anti-coagulate if in AF.
- Treat other conditions such as hypertension, diabetes etc.
What surgical interventions can be offered to patients with valvular dysfunction?
Valve repair
- mainly for mitral valve (e.g. prolapse due to chordae). Not a role for this in calcification.
Valve Replacement
What valve replacement devices are there? What issues are there with these?
- Old fashioned ball and cage had high risk of thrombus
- Tilting disc valves: need warfarin anti coagulation.
- Tissue valves: no need for warfarin, but doesn’t last as long as mechanical valves.
What procedural interventions are available for valvular dysfunction?
TAVI (for aortic stenosis)
- gain access from femoral artery
- patients who are not candidates for open heart surgery
- Tube crushes valve and inflate stent and new valve in position.
Valvuloplasty
- role in mitral valve disease
- younger patients
Mitraclip
- for mitral regurgitation
- clips leaflets together
- still undergoing trials.
