Cardiac Cycle

Question 1

What ECG phase corresponds with the ejection phase?

Answer 1

ST interval

Question 2

Define LVEDV.

Answer 2

volume of blood left in LV at end of diastole

Question 3

Define LVESV.

Answer 3

volume of blood left in LV at end of systole

Question 4

How is SV calculated?

Answer 4

LVESV - LVEDV

Question 5

How is the ejection fraction calculated?

Answer 5

EF = SV / LVEDV

Question 6

What is a normal EF?

Answer 6

60-65%

Question 7

In the PV loop, what point is an index of preload?

Answer 7

LVEDP, LVEDV

Question 8

In the PV loop, what point is an index of afterload?

Answer 8

LVESP

Question 9

What does the area of a PV loop represent?

Answer 9

Work of the heart (not CO)

Question 10

How is MAP calculated?

Answer 10

MAP = CO * TPR
MAP = HR * SV * TPR
MAP = DBP + (1/3)*(SBP - DBP)

Question 11

What is Ohm’s Law?

Answer 11

I = V / R

Question 12

What factors can the body control to regulate MAP?

Answer 12

HR, SV, TPR