Mon25October0757PM 19
A 94-year-old woman sustains a fractured neck of femur following a fall. She is scheduled for urgent surgery.
The clinical history and examination suggests she may have heart failure and an echocardiogram is ordered. The following measurements are available:
End-diastolic volume = 60 ml
End-systolic volume = 40 ml
Which one of the following figures approximates to her calculated ejection fraction?
(Please select 1 option)
53%
33% This is the correct answer
63% Incorrect answer selected
43%
23%
Explanation
The ejection fraction (EF) is commonly measured using echocardiography. This non-invasive technique provides good estimates of end-diastolic (EDV) and end-systolic volumes (ESV), and stroke volume (SV = EDV - ESV).
EF = SV/EDV × 100.
Normally, EF is >55-70%.
In this example:
End-diastolic volume = 60 ml (normally 70-240 ml)
End-systolic volume = 40 ml (normally 16-140 ml).
So,
SV = 60 - 40 = 20
EF = 20/60 × 100 = 33%.
Answer Statistics
1
2%
2
87%
3
3%
4
4%
5
6%
Times answered: 262