Murmurs Flashcards
What does S1 and S2 suggest?
S1 sound –> AV valves closing –> systole starts.
S2 sound –> Semilunar valves –> systole finishes and diastole starts
When can you hear S3 and S4 sound?
What does S3 and S4 sound suggest?
S3 Sound
- After the S2 (0.1sec)
S4
- Before the S1 sound
S3 sound
- Ventricles are filling very rapidly, but because the ventricles are stiff/hypertophy, the chordae tendinae vibrate.
- Indicates heart failure in elderly patients, but not so much in younger patients as their heart functions so well that the ventricles allow for easy rapid filling of the chamber.
S4 sound
- Always abnormal,
- Indicates a very stiff or hypertrophied ventricle.
- The sound is produced by the turbulent flow from an aria contracting against a non-compliant ventricle.
Bell and diaphragm can be used to hear what pitches?
Bell
- Low pitched sounds e.g. mitral stenosis
Diaphragm
- High pitched sounds e.g. aortic regurgitation
What is Erb’s point?
Where is it?
Point where all the heart sounds are heard best.
3rd intercostal space, left sternal edge
How do you assess a murmur?
SCRIPT
Site –> where is the murmur heard best?
Character –> soft/blowing/crescendo (getting louder)/ decrescendo (getting quieter) / crescendo- decrescendo
Radiation –> carotid (aortic stenosis) or axilla (mitral regurgitation)
Intensity –> grade
Pitch –> high/low rumbling –> indicates the velocity of the blood flow through the valve.
Time –> during systole/diastole
Use the following script to describe a murmur.
“This patient has a harsh / soft / blowing, Grade …, systolic / diastolic murmur, heard loudest in the aortic / mitral / tricuspid / pulmonary area, that does not / radiates to the carotids / left axilla. It is high / low pitched and has a crescendo / decrescendo / crescendo-decrescendo shape. This is suggestive of a diagnosis of mitral stenosis / aortic stenosis”
How do you grade a murmur?
Grade 1: Can’t hear
Grade 2: Quiet
Grade 3: Easy to hear
Grade 4: Easy to hear with a palpable thrill
Grade 5: Can hear with a stethoscope barely touching the chest.
Grade 6: Can hear with a stethoscope off the chest.
Categorise whether dilatation or hypertrophy occurs in the following circumstances:
- Mitral stenosis
- Mitral regurgitation
- Aortic stenosis
- Aortic regurgitation
Mitral stenosis
- Atrial hypertrophy
Mitral regurgitation
- Atrial dilatation
Aortic stenosis
- Ventricular hypertrophy
Aortic dilatation
- Ventricular dilatation
What is mitral stenosis?
What are the causes?
What type of sound does it sound?
What clinical features is it associated with?
Mitral stenosis
- Narrowing of the mitral valve.
- As a result, blood flows passes slowly from the left atrium into the left ventricle.
Causes
- Rheumatic Heart Disease
- Infective Endocarditis
Type of murmur
- Mid-diastolic murmur
- Lub Dub Drrrr
- LUB (S1) sound very loud due to hypertrophied mitral valve. You can palpate a tapping apex beat due to the loud S1.
Clinical features mitral valve stenosis is associated with:
- Malar flush –> this is due to back pressure of blood into the pulmonary system, causing a rise in CO2 and vasodilation.
- Atrial fibrillation –> this is because the left atrium struggles to push blood through the stenotic valve causing strain, electrical disruption, resulting in atrial fibrillation.
What is mitral regurgitation?
What are the causes?
What type of sound does it sound?
What clinical features is it associated with?
Mitral regurgitation is when an incompetent mitral valve allows blood the leak back from the left ventricle into the left atrium during systole.
Causes
- Idiopathic weakening of the valve due to age
- Ischaemic heart disease
- Infective endocarditis
- Rheumatic Heart Disease
- Connective tissue disorders such as EDS and Marfan’s syndrome.
Type of Murmur
- Pan-systolic murmur
- Brrrrrrrrrrrr Dub
- High pitched whistling murmur due to the high velocity of blood through the leaky valve.
Clinical association
- Leads to congestive heart failure, because the leaky valve means there is a reduced ejection fraction, and there is a backlog of blood that is waiting to be pumped through the left side of the heart. Due to the heart failure, the patient may also present with a third heart sound.
- This murmur radiates to the left to the left axilla.
What is aortic stenosis?
What are the causes?
What type of sound does it sound?
What clinical features is it associated with?
Aortic stenosis is a narrow aortic valve. As a result, the ventricles find it difficult to push blood from the left ventricle into the aorta.
Causes
- Idiopathic: age related calcification
- Rheumatic Heart Disease
Type of murmur
- Ejection pan-systolic murmur
- High pitched murmur due to the velocity of the blood during systole.
- Crescendo-descrescendo murmur –> this represents the speed of blood flow during different stages of systole.
Clinical associations
- Associated with a slow rising pulse (because blood passes relatively slowly through the aortic valve).
- Associated with a narrow pulse pressure (small difference between systole and diastole) –> this is because blood doesn’t easily pass into the aorta, therefore CO and BP is lower.
- Murmur radiates to the carotid as the turbulence continues up the neck .
- Patients might present with syncope duet to difficulty in maintaining good flow to the brain.
What is aortic regurgitation?
What are the causes?
What type of sound does it sound?
What clinical features is it associated with?
Aortic regurgitation when the incompetent aortic valve, results in blood flowing back into the ventricles during diastole.
Causes
- Idiopathic age related weakness
- Connective tissue disorders e.g. EDS and Marfan’s syndrome
Type of murmur
- Early Diastolic Murmur
- Rumbling murmur –> due to slow leaking of blood back into the ventricles.
- Lub Dub Tarrrr
Clinical association
- Collapsing/Corrigans pulse –> rapid rise and fall in pulse –> this is because the blood flows back into the left ventricle, as soon as its pumped into the aorta.
- Austin Flint Murmur –> early diastolic murmur which can be heard at the apex –> occurs due to blood which is falling back into the ventricles, hitting the mitral valve causing it to vibrate.
