Lecture 3: The Heart pt.2 Flashcards
True or False?
The Ventricular Pressure Volume Loop involves time.
FALSE
In what direction does the Ventricular Pressure Volume Loop go in?
Counter Clockwise
In the corners of the loop, what does it show?
Something happening to the valves
Volume increases and all of a sudden, the volume stops changing and the pressure goes up. Why did the pressure go up?
It means either pressure in the atrium and ventricle are equal OR the atrium and the ventricle are separated because THE MITRAL VALVE IS CLOSED.
Why is the mitral valve closed?
The pressure in the ventricle became higher than the pressure in the atrium.
As pressure goes up, we have another change. The volume of blood in the left ventricle starts to drop. Where’s the blood going?
The LV to the Aorta
How does blood go from the LV to the Aorta? What has to happen?
The Aortic Valve has to open. The volume in the ventricles dropping, pressure is dropping,
What do you know if the volume isn’t changing anymore?
It could be that the pressure in the ventricle and aorta are equal again or the aorta and the ventricle are separated from each other.
As the volume in the LV stops dropping, what happens?
The aortic valve closes
As the volume of blood in the LV ventricle increases again, what happened?
The mitral valve opens
What is the pressure phase when the mitral valve closes to the aortic valve opens?
Isovolumetric contraction
As pressure goes up in the LV, but no more blood is coming in. What happened to cause the pressure to go up?
Contracting
In an isovolemtric contraction, what happens to the ventricles?
The ventricle is isolated because the valves on both ends are closed. The pressure is high enough to close the mitral valve but NOT high enough to open the aortic valve yet.
What phase is between when the aortic valve opens to the aortic valve closes?
Ejection Phase
What happens in the Ejection Phase?
The volume of blood in the ventricle is decreasing.It is being squeezed out to the aorta.
What is the reason the pressure goes first?
Ventricular contraction is so powerful and fast, the ventricle is getting smaller faster than the blood is leaving.
When there’s no change in volume and the pressure drops, what phase occurs?
Isovolumetric Relaxation
What occurs in the Isovolumetric Relaxation phase?
Both the valves are closed and the volume of blood in the LV isn’t changing because the ventricle is relaxing. The box the blood is in is getting bigger and let’s the pressure drop.
If the AV valve is open, what happens to the volume?
the volume has to go up in a normal heart
If the Semilunar valve is open, what happens to the volume?
the volume has to go down
The only way to have the volume not change is…
to have both valves closed.
If the volume is changing, what does this mean?
one of the valves has to be open.
What is the phase when the mitral valve opens to when the mitral valve closes?
Ventricular Filling
What happens to the volume and the pressure in Ventricular Filling?
The volume increases and the pressure drops a little bit and gradually increases.