Disease of heart valves Flashcards
What are the causes of mitral stenosis?
Rheumatic fever Congenital Mucopolysaccharidoses Endocardial fibroelastosis Malignant carcinoid Prosthetic valve
What are mucopolysaccharidoses?
A group of metabolic disorders caused by the absence or malfunctioning of lysosomal enzymes
What is endocardial fibroelastosis?
A rare heart disorder usually associated with children two years old and younger characterized by a thickening of the endocardium due to an increase in the amount of supporting connective tissue and elastic fibers
What is the normal mitral valve orifice area? At what area do symptoms of stenosis begin?
Normal area= 4-6cm squared
Symptoms= <2cm squared
How does mitral valve stenosis present?
Dyspnoea Fatigue Palpitations Chest pain Systemic emboli Haemoptysis Chronic bronchitis-like picture
What are the signs of mitral valve stenosis?
Malar flush on cheeks due to reduced cardiac output
Low-volume pulse
Atrial fibrillation is common
Tapping, non-displaced apex beat- palpable S1
On auscultation: loud S1; opening snap (pliable valve) rumbling mid diastolic murmur. Graham Steell murmur may occur
How is mitral stenosis best heard?
With the bell of the stethoscope
On expiration
With the stethoscope below the left axilla and the patient on their left side
What is a Graham Steell murmur?
An early diastolic murmur. EDMs are high pitched and easily missed and occur as ‘absence of silence’ in early diastole. An EDM occurs rarely in pulmonary regurgitation. If the pulmonary regurgitation is secondary to pulmonary hypertension resulting from mitral stenosis, then the EDM is called a Graham Steell murmur.
How do auscultation sounds change as mitral stenosis becomes more severe?
The more severe the stenosis, the longer the diastolic murmur and the closer the opening snap is to S2
What signs might be seen on an ECG in mitral stenosis?
Atrial fibrillation
RV hypertrophy
Progression right axis deviation
In sinus rhythm, bifid P waves (P mitrale)
What signs might be seen on a CXR in mitral stenosis?
Left atrial enlargement
Pulmonary oedema
Mitral valve calcification
What is the diagnostic test for mitral valve stenosis?
Echocardiography
When is significant stenosis said to exist in mitral stenosis?
When the valve orifice is <1cm square per 1m squared of the body surface area
How is mitral stenosis managed?
- If in AF rate control is crucial
- Anticoagulate with warfarin
- Diuretics to reduce pre-load and pulmonary venous conjestion
- If this fails to control symptoms, balloon valvuloplasty- if pliable, non-calcified valve, open mitral valvotomy or valve replacement
- Infective/subacute bacterial endocaritis prophylaxis for GI/GU infected procedures
- Oral penicillin as prophylaxis against recurrent rheumatic fever
What are complications of mitral stenosis?
- Pulmonary hypertension
- Emboli
- Pressure from larger left atrium on local structures e.g. recurrent laryngeal nerve causing hoarseness, the oesophagus causing dysphagia,
- Bronchial obstruction
- Infective endocarditis
What are the causes of mitral regurgitation?
Functional (LV dilatation) Annular calcification (elderly) Rheumatic fever Infective endocarditis Mitral valve prolapse Ruptured chordae tendinae Papillary muscle dysfunction/rupture Connective tissue disorders (Ehlers-Danlos; Marfan's) Cardiomyopathy Congenital Appetite supressents e.g. fenfluramine
What are the symptoms of mitral regurgitation?
Dyspnoea
Fatigue
Plapitations
Infective endocarditis
What are the signs of mitral regurgitation?
Atrial fibrillation
Displaced, hyperdynamic apex beat
RV heave
Pansystolic murmur
Where does the murmur heard in mitral regurgitation radiate?
The axilla
What is the sign of increasing severity of mitral regurgitation?
The more severe, the larger the left ventricle
What signs might be seen on an ECG of a patient with mitral regurgitation?
Atrial fibrillation
P-mitrale if in sinus rhythm
Left ventricular hypertophy
What signs might be seen on a CXR in a patient with mitral regurgitation?
Big LA and LV
Mitral valve calcification
Pulmonary oedema
As well as an ECG, what other tests may be performed on a patient with suspected mitral regurgitation
Echo: to assess LV function and aetiology (trans-oesophageal to assess severity and suitability for repair rather than replacement)
Coppler echo to assess size and site and regurgitant jet.
Cardiac catheterization to confirm diagnosis, exclude other valve disease and assess coronary artery disease
How is mitral regurgitation managed?
- Control rate if atrial fibrillation
- Anticoagulate if: AF; history of embolism; prosthetic valve; additional mitral stenosis
- Diuretics to improve symptoms
- Surgery for deteriorating symptoms
- Aim to repair or replace the valve before LV irreversibly impaired
- SBE/IE prophylaxis for GI/GU infected procedures
What is the most common valvular abnormality?
Mitral valve prolapse
What is mitral valve prolapse?
Displacement of an abnormally thickened mitral valve leaflet into the left atrium during systole.
“Mitral valve prolapse means that one or more of the mitral flaps are floppy and don’t close tightly, often leading to backflow of blood- mitral regurgitation.
Most people with a mitral valve prolapse will not have symptoms, unless the problem causes severe mitral regurgitation, and it is usually discovered by chance during echocardiography carried out for a different reason.”
What other diseases may occur with mitral prolapse?
ASD Patent ductus ateriosus Cardiomyopathy Turner's syndorme Marfan's syndrome Osteogenesis imperfecta Pseudoxanthoma elasticum WPW
What are the symptoms of mitral valve prolapse?
May be asymptomatic
May occur with atypical chest pain and palpitations
Some patients have symptoms of autonomic dysfunction- anxiety, panic attack, syncope
What signs may be auscultated in a patient with mitral valve prolapse?
Mid systolic click and/or late systolic murmur
What are the complications of mitral valve prolapse?
Mitral regurgitation
Cerebral emboli
Arrhythmias
Sudden death
What is the diagnostic test for mitral valve prolapse?
Echo
What is the treatment for mitral valve prolapse?
Beta-blockers may help palpitations and chest pain
If there is severe mitral regurgitation, surgery may be needed
What are the causes of aortic stenosis?
Senile calcification is the commonest cause
Other causes are congenital (bicuspid valve, Williams syndrome) and rheumatic fever