What is calculated to assess the pumping efficiency of the left ventricle?

• A. Cardiac output
• B. Stroke volume
• C. Ejection fraction
• D. Cardiac index

Answer: (C)

The ejection fraction is a critical measurement used to assess the pumping efficiency of the left ventricle. It is defined as the percentage of blood that is ejected from the left ventricle during each heartbeat compared to the total amount of blood in the ventricle at the end of filling (diastole). A typical ejection fraction is between 55% to 70%, and values below this range may indicate that the heart is not pumping effectively, which could suggest heart failure or other cardiovascular conditions.

This measurement provides valuable clinical insights about the heart's function, allowing healthcare providers to evaluate cardiac health and make informed treatment decisions. By focusing on how much blood is being ejected in relation to the volume available, ejection fraction directly reflects the contractile strength and efficiency of the left ventricle.

In contrast, while cardiac output, stroke volume, and cardiac index are also important parameters related to heart function, they reflect different aspects of cardiac performance. Cardiac output measures the total volume of blood the heart pumps per minute, stroke volume indicates the volume of blood ejected with each heartbeat, and cardiac index relates cardiac output to body surface area, providing a measure that accounts for individual size. Thus, the ejection fraction specifically highlights the