What is stroke volume?

What is stroke volume?

• A. The amount of blood pumped out of the left ventricle during each heartbeat, approximately 70 mL.
• B. The volume of blood remaining in the ventricle after systole.
• C. The total blood pumped by both ventricles per minute.
• D. The volume of blood in the aorta.

Answer: (A)

Stroke volume is the amount of blood ejected from the left ventricle with each heartbeat. In a typical adult, this is about 70 mL. It represents how much blood the heart pumps per beat and is shaped by preload (filling), afterload (the resistance the ventricle must overcome), and contractility (the strength of contraction). This value is different from end-systolic volume, which is the blood that remains in the ventricle after contraction. Cardiac output, the total blood pumped per minute, equals stroke volume times heart rate. The volume in the aorta reflects the arterial blood at a moment in time, not the amount ejected per beat.

Stroke volume is the amount of blood ejected from the left ventricle with each heartbeat. In a typical adult, this is about 70 mL. It represents how much blood the heart pumps per beat and is shaped by preload (filling), afterload (the resistance the ventricle must overcome), and contractility (the strength of contraction). This value is different from end-systolic volume, which is the blood that remains in the ventricle after contraction. Cardiac output, the total blood pumped per minute, equals stroke volume times heart rate. The volume in the aorta reflects the arterial blood at a moment in time, not the amount ejected per beat.