What is the Difference Between Stroke Volume and Cardiac Output?

Stroke volume and cardiac output are two important measurements related to the heart's pumping ability. Here are the key differences between them:

Stroke Volume (SV): Stroke volume is the volume of blood in milliliters ejected from each ventricle due to the contraction of the heart muscle. It is the difference between the end-diastolic volume (EDV) and the end-systolic volume (ESV). SV is affected by factors such as preload, afterload, and contractility. Normal values for a resting healthy individual are approximately 35-65 mL/m².
Cardiac Output (CO): Cardiac output is the amount of blood the heart pumps from each ventricle per minute, usually expressed in liters per minute (L/min). CO is the product of heart rate (HR) and stroke volume (SV). It is dynamically altered by changes in mean arterial pressure (MAP) and total peripheral resistance. Normal cardiac output ranges from 5 to 6 L/min in a person at rest, and it can be more than 35 L/min in an elite athlete during exercise.

In summary, stroke volume represents the amount of blood ejected by the heart with each beat, while cardiac output represents the total amount of blood pumped by the heart per minute. Both measurements are essential for assessing the heart's pumping capacity and overall cardiovascular health.