On echocardiography, which parameter provides assessment of systolic function?

• A. Atrial fibrillation
• B. Ejection fraction
• C. Blood pressure
• D. Hematocrit

Answer: (B)

On echocardiography, systolic function refers to how well the heart muscle contracts and ejects blood during the heartbeat. The parameter that directly quantifies this is the ejection fraction, which expresses the percentage of blood in the ventricle that is pumped out with each beat. It’s calculated as stroke volume divided by end-diastolic volume and is typically estimated from echo images using methods like the Simpson’s rule. Normal ejection fraction is roughly 55–70%; a lower value indicates impaired systolic function, such as in cardiomyopathy or ischemic heart disease.

Atrial fibrillation is an irregular rhythm that can affect how heart chambers fill and how effectively they pump, but it does not itself measure systolic performance. Blood pressure is a systemic measure of arterial pressure, not a direct echo-based assessment of how much blood the ventricle ejects with each contraction. Hematocrit is a blood test showing the proportion of red blood cells, unrelated to cardiac contractile function.