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
What is associated with Mitral stenosis and why ( Hint: 2 conditions )
1- Malar Flush: back pressure of blood into pulmonary system will cause rise in CO2 and vasodilation
2- Atrial Fibrillation : left atrium struggling to push blood will cause electric disruptions
What is Mitral Regurgitation
Incompetent mitral valve allows blood to flow back through during systolic contraction of left ventricle .
What is the end result of Mitral regurgitation
Will result in congestive cardiac failure as leaking valve will reduce ejection fraction and will result in a backlog of blood waiting oil left atria to be pumped through left side of heart.
Describe the murmur caused by mitral regurgitation
Pan-systolic , high pitched whistling ( due to high velocity of blood flow ).
Murmur radiates to left axilla
What heart sound could be heard due to mitral regurgitation
S3
What are the causes of Mitral Regurgitation ( Hint:5)
1- Idiopathic weaning of valve with age 2- Ischaemic heart disease 3- infective Endocarditis 4- Rheumatic Heart Disease 5- Connective tissue disorders ( marfan or Ehlers danlos )
Describe the murmur heard due to Aortic stenosis
Ejection-systolic , high pitched murmur ( high velocity of systole ). Crescendo-decrescendo character due to different blood flow speeds during systole. Murmur radiates to carotid.
What causes the crescendo-decrescendo character or an aortic stenosis murmur
The flow of blood is slowest at the start and end of systole and fastest in the middle.
What are signs of Aortic stenosis other than a murmur
1- Slow rising pulse
2- Narrow pulse pressure
2- Exertional syncope
What are the causes of aortic stenosis ( Hint: 2 )
1- Idiopathic age related calcification
2- Rheumatic Heart Disease
Describe the murmur heard due to Aortic Regurgitation
Early diastolic, soft murmur.
Can cause an Austin-Flint murmur that’s heard at the apex as an early diastolic rumbling murmur.
What sign is aortic regurgitation also associated with
Corrigan’s pulse. collapsing pulse that is rapidly appearing and disappearing at the carotid.
What causes Corrigan’s pulse
Blood pumped out by ventricles immediately flows back through the aortic valve into the ventricles again.
What is the end result of Aortic Regurgitation
Heart failure due to back pressure of blood in left side of heart
What causes the Austin-Flint murmur
blood flowing back through aortic valve and over the mitral valve causes it to vibrate
What are the causes of aortic regurgitation ( Hint: 2)
1- Idiopathic age related weakness
2- Connective tissue disorders ( Marfan or Ehlers )
