The Cardiac Cycle

The Cardiac Cycle

To the tune of "Radio Ga Ga” by Queen

[Verse 1]
In ventricular diastole
The ventricles fill passively
The AV valve is open so
Blood can continue to flow

[Verse 2]
Then comes atrial systole
The atrium will start to squeeze
The last remaining blood into
The ventricle for future use  
The AV valve will finally close
When pressure in the ventricle
Rises above the atrium
Backflow not an option

[Pre-Chorus]
Pressure rises, volume stays the same
It’s the isovolumetric contraction phase  
Cardiac cycling

[Chorus]
Blood will flow from high to low pressure
High to low pressure
High to low pressure
Blood will flow from high to low pressure
High to low pressure
Physics and chemistry
Underly physiology

[Verse 3]
 In ventricular systole
Blood in the heart will finally leave
The pressure is up high enough
The semilunar valves open up
 Blood flows into the arteries
Ventricular pressure starts to decrease
The semilunar valves they close
Once again preventing backflow

[Pre-Chorus]
Pressure falls, volume stays the same
It’s the isovolumetric relaxation phase
Cardiac cycling  

[Chorus]
Blood will flow from high to low pressure
High to low pressure
High to low pressure
Blood will flow from high to low pressure
High to low pressure
Physics and chemistry
Underly physiology