Heart Murmurs Flashcards
What causes the 1st heart sound (S1)
closing of atrioventricular valves ( tricuspid and mitral ) at the start of systolic contraction of ventricles
What causes the 2nd heart sound (S2)
closing of semilunar valves ( aortic and pulmonary ) once systolic contraction is complete
What causes the 3rd heart sound (S3) and when is it heard
Heard 0.1 seconds after S2 , S3 is the sound of chordae tendineae pulling to their full length due to rapid ventricular filling
What can S3 indicate when heard
In elderly patients it can indicate heart failure due to ventricles and chordae being stiff and weak that they reach their limit faster than normal
When can hearing S3 be normal and why
in young healthy people ( 15-40 ) S3 can be normal since the heart functions so well that the ventricles easily allow rapid filling.
What causes the 4th heart sound and when is it heard
S4 is heard directly before S1. It’s abnormal and hard to hear.
Caused by turbulent flow from atria contracting against non-compliant ventricle.
What can hearing a S4 indicate
A stiff or hypertrophic ventricle
Which side of the stethoscope is used to hear low pitched sounds and which is used to hear high pitched sounds
Bell : low pitched
Diaphragm : high pitched
Where is the pulmonary valve located
2nd ICS left sternal border
Where is the Aortic valve located
2nd ICS right sternal border
Where is the Tricuspid valve located
5th ICS left sternal border
Where is the Mitral valve located
5th ICS mid clavicular line ( apex area )
What is Erb’s point and where is it
The area best for listening to S1 & S2 heart sounds.
Located in the 3rd ICS on the left sternal border
What special maneuvers can be used to emphasize certain murmurs ( Hint: 2 )
1- Mitral stenosis : patient on left hand side
2- Aortic regurgitation : patient sat up, leaning forward and holding exhalation
List what is assessed in a Murmur
S: Site ( where is it loudest )
C: Character ( soft/blowing/crescendo/decrescendo)
R: Radiation ( radiate in carotid or left axilla )
I: Intensity ( what grade )
P: Pitch ( low/high/grumbling)
T: Timing ( systolic or diastolic)
Explain how to grade a murmur ( Hint : 6)
1- Difficult to hear 2- Quiet 3- Easy to hear 4- Easy to hear with a palpable thrill 5- Can hear with stethoscope barely touching chest 6- Can hear with stethoscope off chest
When in doubt what grade is the murmur probably
2 or 3
What is the difference between Hypertrophy or Dilation of myocardium
Hypertrophy : thickening outwards and into the chamber
Dilation : thinking and expanding of myocardium
What can cause Myocardial Hypertrophy and give the 2 possible conditions and their result
Pushing against a stenotic valve will cause myocardial hypertrophy.
1- Mitral stenosis = left atrial hypertrophy
2- Aortic stenosis = left ventricular hypertrophy
What can cause Myocardial Dilation and give the 2 possible conditions and their result
Leaky valve allowing blood flow back into a chamber will stretch the muscle resulting in dilation.
1- Mitral regurgitation = left atrial dilation
2- Aortic regurgitation = left ventricular dilation
What is mitral stenosis
Narrowing of the mitral valve that makes it difficult for the left atrium to pump blood through to the ventricle.
What are the causes of Mitral stenosis ( Hint: 2 )
1- Rheumatic Heart Disease
2- Infective Endocaaditis
Describe the murmur caused by Mitral Stenosis
Mid-diastolic , low pitches rumbling murmur ( due to low velocity of blood )
Which heart sound will change due to mitral stenosis
S1 will be loud due to thick valves requiring large systolic force to shut and then shutting suddenly
