Murmurs Flashcards
What are the clinical signs in aortic stenosis?
Syncope
Chest pain
Breathlessness (on exertion)
What are the causes of aortic stenosis?
Bicuspid aortic valve
Age-related calcification
Rheumatic fever
What are the different survival rates depending on the presence of symptoms in aortic stenosis?
Asymptomatic = 1% chance of problems Symptomatic = 2-5 years before problems
What do you hear on auscultation for aortic stenosis?
Ejection systolic murmur
Radiates to the carotids
What are the signs of AS on examination?
Slow rising character of pulse
Low volume pulse
Narrow pulse pressure
Forceful apex beat
What can you see on x-ray with AS?
Dilated and prominent aorta
Relatively small heart
What can you see on ECG with AS?
Left ventricular hypertrophy
Left ventricular strain pattern (ST depression, T wave inversion in LV leads)
What is a murmur?
Sounds produced by turbulent flow of blood through the heart/abnormal valves.
How does inspiration help with identifying murmurs?
Deep inspiration means there is increased venous return to the heart. This means that it causes right sided murmurs to increase in intensity.
How does expiration help with identifying murmurs?
Deep expiration means there is an increased afterload from the heart, therefore causing left sided murmurs to be loudeste.g. - aortic stenosis and mitral regurgitation
Define stenosis
Obstruction to the normal flow of blood
Define regurgitation
Failure to prevent the back-flow of blood through the valve.
What can causes valvular disease?
Direct damage to the valve leaflets
Secondary to damage to the papillary muscles
What are the major causes of mitral stenosis?
Rheumatic fever- some people have calcification due to old age
What are the major causes of mitral regurgitation?
Rheumatic fever Mitral valve prolapse Papillary muscle dysfunction (post MI) Valve ring dilatation Cardiomyopathy Connective tissue disorders
What are the major causes of aortic regurgitation?
Rheumatic fever Aortic dilatation Rheumatological disorders Infective endocarditis Bicuspid valve
What occurs as a result of mitral valve calcification?
Calcification can causes stiffening of the valve cusps which leads to narrowing of the lumen. This narrowing leads to left ventricular hypertrophy as the muscle has to contract harder in order to force the blood through the narrowed lumen.
Define myxomatous degeneration
Degeneration of the connective tissue which holds the mitral valve in place. This occurs alongside a build up of dermatan sulfate (a glycosaminoglycan). This degeneration causes prolapse of the valve during systole, causing regurgitation.
Describe rheumatic heart disease
Occurs as a result of rheumatic fever - an autoimmune reaction caused by infection with group A streptococci, usually in the throat. Occurs in 5-15 year olds but is becoming rarer in the UK.
Where does rheumatic disease have an effect in the body?
Heart
Skin
Joints
CNS
What are some common symptoms with rheumatic fever?
Fever
Arthralgia
Leucocytosis
What is the pathophysiology of rheumatic disease in the heart?
Carditis which causes granulomatous regions in the heart with an area of central necrosis. Initially, there is infiltration of macrophages, lymphocytes and plasma cells. Eventually these will be replaced with fibrous tissue. There can be development of small nodules on mitral valve itself, made up of platelets a fibrin. They are known as Aschoff nodules which are areas of inflammation of connective tissue.
Describe infective endocarditis
Infection of the endocardium or vascular endothelium. Classed according to the causative organism.
Give some characteristics of the valves that are commonly affected by infective endocarditis
Previously damaged valves Valves with congenital abnormalities
What are some of the main causative agents for infective endocarditis?
Streptococcus viridans Staphylococcus aureus Enterococcus faecalis Coxiella burnetti Aspergillus Candida
What are the complications of infective endocarditis?
Acute valve incompetence
Emboli to the spleen, kidneys and brain
Glomerulonephritis and failure
What are the effects of mitral stenosis on the heart?
Increased LA pressure causing pulmonary venous and arterial hypertension. This then causes increased back-flow in the lungs which causes right ventricular hypertrophy in order to overcome the pressure in the lungs. Tricuspid regurgitation can then arise from this and ultimately lead to right heart failure.
Give some signs of mitral stenosis
Atrial fibrillation
Malar flush
Tapping apex beat - due to palpable 1st heart sound
What can you hear on auscultation of mitral stenosis?
Loud S1
“Opening snap” - high pitched sound just after S2
Rumbling mid-diastolic murmur- best heard with the bell over the apex with the patient lying on their left.
What can you see on x-ray with mitral stenosis?
Enlarged left atrium
Signs of pulmonary oedema
What are the signs of pulmonary oedema on CXR?
Bilateral increased lung markings (bat winged shaped)
Kerley B lines
Meniscus sign
Obliteration of hemidiaphragm and costophrenic angle
Blunting of the costophrenic angle
What are Kerley B lines?
Build up of fluid in the secondary lobules of the lungs.
Give some signs of mitral regurgitation
Sinus rhythm
Malar flush
Displaced apex beat (volume overload)
Palpable thrill
What can you hear on auscultation of mitral regurgitation?
Pansystolic murmur
Radiates to the axilla
What can you see on xray in mitral regurgitation?
Cardiomegaly- due to left atrial and left ventricular enlargement
What do you see on ECG with mitral regurgitation?
Bifid P waves
Left ventricular hypertrophy
Describe the pathology of aortic regurgitation
Blood refluxes from the aorta to the left ventricle during diastole. In order to pump out sufficient blood, the cardiac output must increase therefore there needs to be an increase in the size of the left ventricle in order to cope with this.
Give some signs of artic regurgitation
Collapsing pulse
Displaced apex beat
What can you hear on asucultation of aortic regurgitation?
High pitched early diastolic murmurBest heard at L sternal edge in the 4th intercostal space with the patient leaning forward and holding their breath in inspiration.
What can you see on ECG with aortic regurgitation?
Left ventricular hypertrophy
What are the three classification of atrial fibrillation?
- Paroxysmal – intermittent, self-terminating episodes
- Persistent – prolonged episodes, terminated by electrical or chemical cardioversion
- Permanent
What signs would you get with atrial fibrillation?
- Irregularly irregular heart rate
- Hypertension
What symptoms can be causes by atrial fibrillation?
Palpitation
Breathlessness
Fatigue
With which diseases can atrial fibrillation occur?
- Coronary artery disease
- Valvular heart disease
- Hypertension
- Hyperthyroidism
- Cardiomyopathy
- Congenital heart disease
- Idiopathic
- Pulmonary embolism
- Chest infection
Give the pathology of atrial fibrillation
Abnormal autonomic firing and the presence of multiple interacting re-entry loops.
Give some causes of an ejection systolic murmur
Aortic stenosis Pulmonary stenosis HOCM ASD Tetralogy of Fallot
What can cause a a pansystolic murmur?
Mitral regurgitation
Tricuspid regurgitation
VSD
What causes a late systolic murmur?
Mitral valve prolapse
Coarctation of the aorta
What causes an early diastolic murmur?
Aortic regurgitation
Pulmonary regurgitation
What causes a mid to late diastolic murmur?
Mitral stenosis
Severe aortic regurgitation
What causes a continuous machine-like murmur?
Patent ductus arteriosus
Describe a venous hum
Innocent murmur heard in children
Due to turbulent blood flow in the great veins returning to the heart. Continuous blowing noise just below the clavicles.
Give some characteristics of an innocent ejection murmur
Varies with posture Localised, no radiation No thrill No added sounds Asymptomatic child
