Week 5 Flashcards
What is the normal range of the mitral valve area?
4-6 cm^2
what is the normal size range of the aortic valve?
3-4 cm^2
What is mitral stenosis?
- Mitral stenosis (MS) is the impaired opening of the mitral valve affecting blood flow from the left atrium to the ventricle.
mitral stenosis aetiology
rheumatic heart disease
congenital mitral stenosis
systemic conditions: systemic lupus erythematosus, rheumatoid arthritis.
what is long QT syndrome? and what can it cause?
A normal QT interval is less than 440ms (two large squares).
Any interval above 450 ms is considered prolonged.
This can lead to prolonged ventricular repolarisation which predisposes to malignant ventricular arrhythmias.
discuss the genetics of long QT syndrome
Genetic (Sodium or potassium channel mutations):
- Jervell and Lange-Nielson syndrome (associated with deafness).
- Romano Ward Syndrome.
discuss the investigations of long QT syndrome
Electrocardiogram +- 24 hour tape
Echocardiogram to look for structural heart disease
Genetic testing as required
discuss the management of long QT syndrome
Beta blockade
Cardiac Pacing
Manage underlying cause
Implantation of ICD
what is cardiomyopathy?
A structural and functional abnormality of the myocardium without coronary artery disease, hypertension, valvular or congenital heart diseases.
what are the main subtypes of cardiomyopathy?
Dilated - most common
Hypertrophic
Restrictive
Arrhythmogenic right ventricular cardiomyopathy
what is dilated cardiomyopathy? where does it typically start? what does it make more difficult?
Myocardium disease that causes the ventricles to thin and stretch, growing larger. It typically starts in the left ventricle. Dilated cardiomyopathy makes it harder for the heart to pump blood to the rest of the body.
discuss the genetics of dilated cardiomyopathy
Genetic and congenital - may be related to familial dilated cardiomyopathy, however some sporadic gene mutations may be responsible for idiopathic cases. Autosomal dominant in most cases.
epidemiology of hypertrophic cardiomyopathy? what is it often the cause of?
Hypertrophic cardiomyopathy is the commonest genetic heart condition. It is often the cause of sudden cardiac death in young people and athletes.
discuss the inheritance of hypertrophic cardiomyopathy
It is inherited in an autosomal dominant fashion.
Mutations can be identified in approximately 60% of patients.
discuss the genetics and aetiology of turners syndrome
Turner’s syndrome is a condition that affects only females and results when one of the X chromosomes is missing or partially missing.
discuss the cardiovascular presentation of Turner’s syndrome
Congenital heart defects - bicuspid aortic valve (most common), coarctation of the aorta.
This increases the risk of aortic stenosis and/or aortic dissection.
what are some genetic causes or aortic regurgitation?
congenital disease e.g., bicuspid aortic valve
Marfan’s syndrome
what are some causes of aortic root dilatation?
Congenital bicuspid aortic valve
Genetic syndromes e.g. Marfan’s, Ehlers-Danlos, osteogenesis imperfecta
pulmonary stenosis is often acquired and associated with which syndromes?
Noonan syndrome (valvular)
Williams syndrome (supravalvular)
Tetralogy of Fallot (valvular)
What is Brugada’s syndrome?
Brugada syndrome is a genetic condition caused by sodium channelopathies.
what are the clinical features of Brugada’s syndrome?
Patients may be asymptomatic or present with palpitations and syncope due to arrhythmias such as AV nodal re-entrant tachycardias (AVNRTs), VT or VF.
what is mitral stenosis?
Mitral stenosis (MS) is the impaired opening of the mitral valve affecting blood flow from the left atrium to the ventricle.
aetiology of mitral stenosis
o Rheumatic heart disease.
o Congenital mitral stenosis.
o Systemic conditions: systemic lupus erythematosus, rheumatoid arthritis.
what is mitral regurgitation?
- Mitral regurgitation (MR) is the backflow of blood across the mitral valve during systole due to incompetence of the mitral valve.
mitral regurgitation aetiology
o Rheumatic heart disease.
o Mitral valve prolapse (MVP).
o Infective endocarditis (IE).
o Degenerative.
o Functional MR due to LV and annular dilatation.
what is aortic stenosis?
- Aortic stenosis is a narrowing of the aortic valve opening and is one of the most common and serious heart problems.
aortic stenosis aetiology
o Degenerative.
o Rheumatic.
o Bicuspid aortic valve.
aortic regurgitation definition
- Aortic regurgitation (AR) is the reverse flow of blood across the aortic valve in diastole due to the incompetence of the valve.
aetiology of aortic regurgitation
o Aorta:
Dilated aorta (Marfans, hypertension).
Connective tissue disorders.
o Leaflets:
Bicuspid aortic valve.
Rheumatic heart disease.
Endocarditis.
Myxomatous degeneration.
Criteria and pathophysiology of mitral stenosis
-mitral valve orifice < 2cm^2
-left atrium pressure increases
-pulmonary venous and capillary pressure increases
-pulmonary vascular resistance increases
-pulmonary hypertension develops
-right heart dilatation with tricuspid regurgitation and pulmonary regurgitation
Criteria and aetiology of aortic stenosis
o AVA < 1.5-2 cm2.
o Rheumatic: retraction and stiffening of free cusp margins.
o Degenerative: linked to atherosclerosis.
pathophysiology of aortic regurgitation
o LV accommodates both SV and regurgitant volume.
o Increased LV end-diastolic volume and LV systolic pressure.
o LV hypertrophy and LV dilatation.
o Increased myocardial oxygen consumption.
o Myocardial ischaemia.
o LV failure.
symptoms of mitral stenosis
dyspnoea
palpitations if in AF
heart failure
haemoptysis
signs of mitral stenosis
malar flush
tapping apex beat and diastolic thrill
hoarse voice
irregularly irregular pulse if in AF
auscultation: low-pitch mid-diastolic murmur with opening snap
symptoms of acute MR (valve perforation, chordal/papillary muscle)
breathlessness, pulmonary oedema, cardiogenic shock
chronic mitral regurgitation symptoms
o Fatigue, exhaustion (low CO), right heart failure.
o Dyspnoea or palpitations due to atrial fibrillation.
symptoms of aortic stenosis
syncope
dyspnoea
angina
heart failure
signs of aortic stenosis
narrow pulse pressure
slow rising pulse
aortic regurgitation symptoms
dyspnoea
angina
heart failure
complications of aortic stenosis
sudden cardiac death
arrhythmia
heart failure
infective endocarditis
complications of aortic regurgitation
heart failure
arrhythmia
infective endocarditis
complications of mitral stenosis
AF
heart failure
infective endocarditis
complications of mitral regurgitation
AF
heart failure
infective endocarditis
pulmonary hypertension
aortic stenosis investigations
ECG: LV hypertrophy; AV block.
CXR: poststenotic dilation of the ascending aorta; may see calcification of valve on lateral view.
ECHO: confirms diagnosis; allows severity and valve area to be assessed.