Cardiac Simulation Flashcards
What occurs when the pressure in the left ventricle exceeds that of the aorta?
Aortic valve opens
What happens when the pressure in the left ventricle exceeds the pressure in the left atria?
Mitral valve closes
What occurs when the pressure in the aorta exceeds that of the left ventricle?
Aortic valve closes
What happens when the pressure in the left atria exceeds that of the left ventricle?
Mitral valve opens
Describe the Atrial Systole of the Cardiac Cycle.
Filling of the ventricles until the atrioventricular valves close as the pressure in the ventricles exceeds that in the atria.
Describe the Isovolumic Contraction of the Cardiac Cycle.
Left ventricular pressure increases until the aortic valve opens.
Describe the Ejection of the Cardiac Cycle.
Ventricular muscles shorten and contract, ejecting blood from the heart in two phases: rapid and reduced.
Describe the Isovolumic Relaxation of the Cardiac Cycle.
The left ventricular pressure decreases below the the aortic pressure and so the aortic valve closes.
Describe the Ventricular Filling of the Cardiac Cycle.
The left ventricle falls below atrial pressure and so the mitral valve opens and the atria can begin to fill the ventricles in two stages: rapid and reduced.
Why is there Reduced Ejection?
Reduced ejection occurs because of:
1) Increased after load as it has increased due to the ventricles pumping blood out of the aorta
2) Cardiac muscle has already shortened a lot and so it has already shortened sarcomeres.
Why is there Reduced Filling?
The tension increases as the ventricles are filled and so when they are close to being full they resist filling more and so it fills slower.
What is the normal pressure of the right atria?
2 mmHg
What is the normal pressure of the left atria?
6 mmHg
What is the normal pressure of the right ventricle?
2 mmHg
What is the normal pressure of the left ventricle?
6 mmHg