3. In the clinic, radiologists measure Ejection Fraction, End Systolic Volume (E

Question

3. In the clinic, radiologists measure Ejection Fraction, End Systolic Volume (ESV), and End Diastolic Volume utilizing a cardiac MRI. The images shown below are cross sections of the Left Ventricle. This is known as the "short-axis" view of the heart KEY 1. Right Ventricle 2. Left Ventricle 3. Diaphragmatic Fat . Paracardiac Fat 5. Chest Wall 6. Liver 7. Stomach 8. Left Lung 9. Right Lung 9 9 6 (a) Which image, left or right, is end systole? Which image is end diastole? Justify your answer. (b) Given that the left ventricular volume in the left image is 142 mL and the left ventricular volume in the right image is 47 mL, what is the Stroke Volume? What is the Ejection Fraction? (c) At rest the Heart Rate is approximately 60 bpm. However, during cardiac MRI, many patients are given a blocker, like metoprolol, which slows the heart rate to 40 bpm. What is the Cardiac Output at (i) rest, and (ii) during the scan with metoprolol?

Explanation / Answer

Left image is at end diastole and right image is in end systole.As the ventricles on right are small( contracted -in systole) and the ventricles an left are large (relaxed- in diastole)

B-stroke volume is the difference between end diastolic volume and end systolic volume.

SV. = EDV. - ESV= 142-47=. 95ml

Ejection fraction= SV *100/EDV=95*100/142=67%

c-Cardiac output= SV* HR

At rest,CO=95*60=5700 ml

with Metropol,CO= 95*40=3800ml

Related Questions

Navigate

• Browse (All)
• Browse 3
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.