Review 1

Question 1

What does the end-systolic PV line denote

Answer 1

Contractility

Question 2

What does the end-diastolic PV line denote

Answer 2

elastance (preload)

Question 3

Describe the effects of increasing preload

Answer 3

End diastolic volume increases
Afterload line shifts to the right (gradient remains the same)
End-systolic PV line remains the same
End-systolic pressure increases
Stroke volume increases

Question 4

What are the effects of decreasing preload

Answer 4

End-diastolic volume decreases
Afterload line shifts to the left (but the gradient remains the same)
End-systolic PV line remains the same
End-systolic pressure decreases 
Stroke volume decreases

Question 5

Describe the effects of increasing afterload

Answer 5

End-diastolic volume remains the same
The gradient of the afterload line increases and shifts to the right
End-systolic PV line remains the same
End-systolic pressure increases 
Stroke volume decreases

Question 6

Describe the effects of decreasing afterload

Answer 6

End-diastolic volume remains the same
The gradient of the afterload line decreases and shifts to the left
The end-systolic PV line remains the same
End-systolic pressure decreases
Stroke volume increases

Question 7

Why does end systolic volume increase with increases in preload

Answer 7

More blood fills the ventricle, hence unless contractility increases, end systolic volume will increase as more blood will be left in the heart after it contracts

Question 8

Describe what happens in aortic stenosis

Answer 8

End-diastolic volume increases (as ESV increases- head-start upon filling blood)
The afterload line moves to the right and its gradient increases
ESPVR line remains the same
ESV increases
SV decreases

Question 9

Why do we get parallel lines on the PV line during the isovolumetric phases

Answer 9

The valves are completely sealed, this is lost in aortic regurgitation.