AEMCA Practice Exam

What is stroke volume?

1. The volume of blood pumped by the heart in one day

2. The amount of blood pumped out of the ventricles during one contraction

3. The total blood volume circulated by the body per minute

4. The difference between end-diastolic and end-systolic volume

The correct answer is: The amount of blood pumped out of the ventricles during one contraction

Stroke volume refers to the amount of blood that is ejected from the ventricles of the heart with each contraction. This measurement is crucial in understanding cardiac performance and overall heart function. It helps in assessing how effectively the heart is functioning to meet the body's demands for blood and oxygen. In this context, stroke volume can be defined as the blood pumped out of the ventricles during one heartbeat, which directly influences cardiac output when multiplied by heart rate. This is fundamental for understanding cardiovascular health, particularly in conditions such as heart failure or during exercise. Other options describe related but distinct concepts. For instance, the total blood volume circulated by the body per minute refers to cardiac output, which is the product of stroke volume and heart rate. The volume of blood pumped by the heart in one day is a cumulative measure of cardiac output over 24 hours. Lastly, the difference between end-diastolic volume and end-systolic volume is an important measure known as ejection fraction, which indicates how much blood is being pumped out relative to the amounts of blood in the ventricles at different points in the cardiac cycle. Understanding these distinctions is key for anyone studying cardiovascular physiology.