Cardiology - Abnormal Heart Sounds Flashcards
What causes S1?
Tricuspid and Mitral Valve closure
What causes S2?
Aortic and Pulmonary Valve closure
What is between S1 and S2?
Systole - Ventricular contraction.
What is S3?
After S2, when blood is flowing from ventricles as mitral and tricuspid are open.
Rapid filling of the ventricles, causing blood to bounce off the wall of the ventricle.
Lub Dub Tah.
What are the physiological causes of an S3?
Normal in - Trained athletes and pregnancy. Simply because the ventricles are handling extra blood.
What are the pathological causes of an S3?
Sign of volume overload
- Congestive heart failure because there is too much volume in the ventricles.
What is S4?
Sound just before S1 at the end of diastole.
Atria contract to get the last bit of blood into the ventricles.
If the ventricles are stiff so can’t relax as much, it creates S4.
Ta lub dub.
What are the pathological causes of S4?
A result of pressure overload.
Severe HTN
This is because the ventricle is stiff and hypertrophied therefore the heart has to pump against high pressure.
Murmur gradings?
1 = Slightest possible murmur 3 = Moderate 6= Heard without the stethoscope
What are innocent heart murmurs?
Some children have perfectly healthy hearts but may have murmurs due to their walls being thin and vibrate with rushing blood.
These murmur’s disappear as a child gets older and the heart wall thicken.
What is a Still’s murmur?
Very common among young children
Heart at the left lower sternal border.
What are the systolic murmurs?
Lub - WHOOSH - Dub
Aortic and pulmonary are open and tricuspid and mitral are closed.
Causes of a systolic murmur?
Aortic or pulmonary valve stenosis.
Mitral or tricuspid regurgitation.
What occurs in aortic or pulmonary valve stenosis
The valve resists opening up before snapping open.
Causes an ejection click.
This is due to increased turbulence causing a murmur.
Why is aortic or pulmonary stenosis a crescendo-decrescendo murmur?
Initially louder as more blood tries to squeeze through.
As there is less blood left in the ventricle it gets quieter.
