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S3 and S4 Heart sound

10K views 4 replies 2 participants last post by  npktun 
#1 ·
when you have s3 heart sound so that always mean you will have an s4 heart sound ....?

S3 --- occurs due to volume overload in the ventricles
S4----occurs due to decreased compliance ---> concentric hypertrophy and volume overload are responsible for it

But you can have an independent s4 heart sound ....

Am i messing something up ..... ?
 
#2 ·
S3 heart sound is also called ventricular gallop. It occurs due to the rapid ventricular filling against an already filled ventricle. Happens in CHF, in any pathology where blood isnt being pumped out from that ventricle effectively.

S4 heart sound happens just before the S1 (the atrioventricular valve closure). You can also call it atrial gallop, and its due to contraction of the atrium to eject that last amount of blood remaining in the atrium, but against a non-compliant ventricle. This usually happens in hypertrophied or stiff ventricles. To contrast, the S3 will happen when there is too much blood in the ventricle, and has nothing to do with the compliance of it.

Can someone else confirm?
 
#3 ·
S3 heart sound is also called ventricular gallop. It occurs due to the rapid ventricular filling against an already filled ventricle. Happens in CHF, in any pathology where blood isnt being pumped out from that ventricle effectively.

S4 heart sound happens just before the S1 (the atrioventricular valve closure). You can also call it atrial gallop, and its due to contraction of the atrium to eject that last amount of blood remaining in the atrium, but against a non-compliant ventricle. This usually happens in hypertrophied or stiff ventricles. To contrast, the S3 will happen when there is too much blood in the ventricle, and has nothing to do with the compliance of it.

Can someone else confirm?
Goljan says so ..... look in heart disorders under heart sounds ..... compliance will be decreased in overload due to ventricles already dilated ....the muscle fibres already reached its maximal length so they would expand less exponentially with increasing force (here filling of blood ) ....analogy to rubberband already stretched may be suitable here ....it will stretch less and will require more force to stretch and we can say its compliance has decreased
 
#5 ·
but apart from goljan .... dont you think increasing volume and dilating it will decrease compliance ...... as the muscle length increases don't you think the muscle will tend to expand less because its already stretched to its near to maximum length ..... ? and it will then take more force to expand (filling of blood) per unit increase of volume? what do you say ?
 
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