What is cardiac output and how is it calculated?

Cardiac output is defined as the volume of blood the heart pumps per minute. It is a crucial parameter in assessing the heart's efficiency and the overall circulatory system's functionality. Cardiac output can be calculated by multiplying the heart rate (the number of beats per minute) by the stroke volume (the amount of blood ejected by the heart with each beat). This relationship illustrates how the heart's performance is essential for delivering oxygen and nutrients to tissues throughout the body and how changes in either heart rate or stroke volume can significantly impact overall cardiac output.

Other choices describe important cardiac concepts but do not accurately reflect the definition of cardiac output. The pressure exerted by the heart during contraction pertains to blood pressure rather than output. The rate of blood flow in systemic circulation can relate to output but is a broader term that encompasses more than just the heart’s pumping capacity. The amount of oxygen delivered to tissues per minute is functionally related to cardiac output but does not represent cardiac output itself; rather, it is an outcome of effective circulation.