Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle The first phase - Atrial Systole
The atria contract and that’s what we see Well it starts with the P wave on the EKG
The atria depolarize and that’s the key- You see that starts the atrial contraction
Atrial pressure increases in that fashion The blood flows into the ventricles
And we continue with the cardiac cycle Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle Then we have the QRS complex
The ventricles depolarize and what comes next Is the contraction of the ventricles and yes
The pressure increases cause the blood is compressed
This next phase is iso-volumetric The blood wants to leave
but the valves won’t let it When the pressure’s high
enough it gets quite dramatic Cause the valves swing open
and the blood gets to exit Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle This next part has the T wave
The ventricles repolarize in this phase Since they repolarize, the ventricles relax
The pressure decreases, these are the facts Isovolumetric relaxation
It’s like the ventricles are on a little mini vacation
The AV valves open - there’s passive filling And the cycle starts over
so that we can keep living Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle So you might be wondering about the lub dub
Man, it’s all about the valves in this vital hub- The AV valves closing gives the sound lub
The semilunar valves closing is this part dub Now we gotta wrap this up with some definitions
Systole - that just means contraction Diastole - that one means relaxation
Cardiac cycle that’s it, now let’s have some fun Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle Lub dub, lub dub, there goes the heart
Lub dub, lub dub, it’s doing its part Systole, diastole - both are vital
Lub dub, lub dub, it’s the cardiac cycle Lub dub, lub dub, there goes the heart -
hey - I hope you enjoyed the cardiac cycle song I wanted to let you know that I did
put together a free guide to help you go deeper into the cardiac cycle so that you
can understand it even better you can get access to that by going to the cardiac cycle.com
check it out or you can click on the link in the description below my name is Leslie Samuel
from interactive biology where we're making biology fun and I'll see you in the next video
love dub love du there goes the heart - hahaa