Ventricular Pressure - Volume Loops

Question 1

What are the 4 ‘corners’ of a ventricular pressure volume loop?

Answer 1

mitral valve closing
aortic valve opening
aortic valve closing
mitral valve opening

Question 2

What happens to the ventricular pressure volume loop with an increased pre-load?

Answer 2

fatter (rightways), as pressure increased with a constant volume

Question 3

What happens to the ventricular pressure volume loop with an increased afterload?

Answer 3

taller and thinner, as more isovolumetric contraction required , and a reduction in stroke volume

Question 4

What doe increasing inotropy mean?

Answer 4

increases the velocity of muscle fibre shortening at any given preload and afterload

Question 5

What does increasing inotropy do to the ventricular pressure volume loop?

Answer 5

makes it fatter (leftways)
increased inotropy allows the ventricle to increase the rate of pressure development and ejection velocity, increasing stroke volume