Cardiac Cycle Flashcards
What occurs during ventricular systole?
Ventricular contraction
What occurs during ventricular diastole?
Ventricular relaxation
At what point in the cardiac cycle is left ventricular systolic pressure at its peak?
In systole
Is there higher systolic pressure in the left or right ventricle?
Left
What causes the slight increase in ventricular pressure at the end of ventricular diastole?
Atrial contraction resulting in blooding being pushed into the ventricle
What is the first isovolumetric phase?
Isovolumetric contraction
What occurs at the beginning of isovolumetric contraction?
The AV valve closes
What occurs at the end of isovolumetric contraction?
Opening of the aortic valve and ejection of stroke volume
What is the second isovolumetric phase?
Isovolumetric relaxatino
What occurs at the beginning of isovolumetric relaxation?
The aortic and mitral valves close
What happens at the end of volumetric relaxation?
The AV valve opens, blood begins to passively fill the ventricle
At what point in the cardiac cycle does atrial systole occur?
At the end of ventricular diastole
What happens to aortic pressure during diastole?
It decreases but never drops to ventricular pressure
How does the aortic pressure stay high during diastole?
The aortic valve is closed and the elastic fibers of the aortic wall push back on blood
What is the physiologic importance of high aortic pressure during systole?
The aortic pressure gradient is the driving force of blood flow through the systemic circulation
