How is cardiac output calculated?

Cardiac output is a vital measure in cardiovascular physiology that reflects the volume of blood the heart pumps per minute. It is calculated using the relationship between heart rate and stroke volume. The heart rate represents the number of times the heart beats in one minute, while stroke volume is the amount of blood ejected by the heart with each beat.

To determine cardiac output, you multiply the heart rate by the stroke volume. This product gives you the total volume of blood pumped by the heart in one minute, which is expressed in liters per minute (L/min). This formula highlights the significance of both the frequency of heartbeats and the efficiency of each contraction in determining overall blood flow and, consequently, the body's ability to meet its metabolic demands.

The other methods mentioned, such as dividing heart rate by stroke volume or combining stroke volume with blood pressure, do not accurately reflect the mechanics of how cardiac output is measured. Blood volume considered with heart rate does not yield the cardiac output directly either, as it misses the essential stroke volume component.