Which diagnostic test is primarily used to assess left ventricular ejection fraction in heart failure?

• A. Echocardiography
• B. Chest radiography
• C. Electrocardiography
• D. Cardiac MRI

Answer: (A)

Assessing left ventricular ejection fraction in heart failure is best done with echocardiography because ultrasound imaging provides real-time visualization of the heart’s chambers and contraction, allowing calculation of LV volumes and the fraction of blood ejected with each beat. By using methods like the biplane Simpson’s rule, echo yields a numerical LVEF, which directly reflects systolic function and helps classify heart failure, guide treatment, and track changes over time. In addition to LVEF, echocardiography offers information about chamber size, wall motion, and valve function, all without radiation and with wide availability, often at the bedside.

Chest X-ray can hint at congestive changes but does not quantify LVEF. ECG shows rhythm and conduction or ischemia but not the amount of blood the ventricle pumps. Cardiac MRI can measure LVEF with high accuracy and may be used when precision is needed or echo windows are poor, but it is less accessible, more costly, and less practical in many clinical settings, making echocardiography the primary test for this purpose.