Valvular heart disease and murmurs Flashcards
Aortic stenosis
- Causes
Most common= Age-related degeneration (>60)
- Bicuspid aortic valve (40-60 yrs)
- Rheumatic heart disease
- Congenital syndromes
Aortic stenosis
- Pathophysiology
Stenosed aortic valve causes resistance in ejecting blood from L ventricles
- Pressure overload.
More pressure is generated in LV to overcome obstruction causes left ventricular hypertrophy.
Decompensation leads to LV dilation and LVHF.
Aortic stenosis
- Heart murmur
Ejection systolic murmur
- Crescendo/descendo
Tuburlence when blood ejecting and building up of pressure to overcome resistance causes crescendo/descendo sound.
If stenosis is severe and valve doesn’t close= Soft S2.
Symptoms of Aortic stenosis
Symptoms stem from less blood ejected from LV
- Dizziness
- Syncope
- Dyspnoea/ fatigue
- Chest pain if underlying IHD
Examination signs of AS
- Pulse
- Pericordium
Pulse
- Slow rising
- Narrow pulse pressure
Pericordium
- Murmur heard clearest when leaning forward in end expiration
- Murmur radiation to carotid
- Forceful, Non-displaced apex
- Aortic thrill
Investigations for heart murmurs
Bloods (usual work up, heart failure risk factors/ screening)
- FBC, U+E
- NT-proBNP/ BNP
- Lipids and glucose
Consider screening for connective tissue disorders/ rheumatic disease
Imaging
- Echo: valvular deformities, abscess/ vegetations, EF, Chamber dilation/ hypertrophy
- CXR: chamber hypertrophy/ cardiomegaly.
- calcified valves, pulmonary oedema.
- Dilated aorta
ECG
- Signs of ischaemia indicating IHD
- Signs of electrical deviation indicating hypertrophy
- Signs of AF esp for MS/ MR.
Aortic regurgitation
- Causes
Valvular
- Degeneration
- Bicuspid valve
- Infective endocarditis
Aortic dilation- due to loss of supporting structures
- Connective tissue disease: Marfan’s, Ehler’s danlos
- Autoimmune: RA, anky spend
- Hypertension: pressure overload causes dilation
- Aortic dissection
- Cystic medial necrosis
- Syphilis
AR
- Pathophysiology
AV does not close properly, blood re-enters LV during systole.
- Leads to fluid overload of LV
Fluid overload causes LV dilation
- Eventual decompensation then LVHF.
AR
- murmurs
Turbulence when blood is ejected and after systole due to blood re-entering LV
- Causes high pitched EARLY DIASTOLIC murmur
If turbulence during ejection
- concordent systole murmur
AR
- Symptoms
Often asymptomatic
Chest pain
- When demand exceeded supply or due to IHD
Dyspnoea
Syncope is uncommon
AR signs
- Pulse
- Pericordium
Pulse
- Collapsing pulse
- wide pulse pressure
Pericordium - Aortic thrill - Displaced, forceful apex beat due to dilated ventricle - High pitch early diastolic murmur. Louder sitting forward, end expiration.
Mitral stenosis
- Causes
Most common= rheumatic disease/ fever
Others
- Degenerative
- Congenital
- Storage disease (mucopolysaccharides)
- Malignancy
MS
- Pathophysiology
MV does not open properly
- Causes back up of blood into lungs leading to pulmonary hypertension/ oedema
- Causes pressure overload in LA trying to overcome resistance= LA hypertrophy and dilation
Murmur is mid diastolic rumble
- Blood turbulence when ventricles filling in diastole
MS
- Murmur
Mid-diastolic rumble
- Due to turbulence when ventricles are filling
- Early diastole snap when blood is forced against stenosed valve
MS
- Symptoms
Caused by blood back up into lungs
- Dyspnoea
- Chest pain
- Haemoptysis
If dilation occurs and AVN is affected= AF, compression
- Palpitations
- Stridor, dysphagia
Malar rash= severe
