Which term describes the force or pressure the ventricle must overcome to eject blood?

Which term describes the force or pressure the ventricle must overcome to eject blood?

• A. End diastolic volume
• B. The pressure the ventricle must overcome to eject blood
• C. Ejection fraction
• D. Cardiac Output

Answer: (B)

Afterload is the force or pressure the ventricle must overcome to eject blood. It reflects the pressure the ventricle must push against, primarily the aortic (or pulmonary) arterial pressure and systemic vascular resistance. When afterload is high, the ventricle has to work harder to open the aortic valve and propel blood forward, which can reduce stroke volume if contractility doesn’t compensate. End diastolic volume is the amount of blood in the ventricle at the end of filling (preload). Ejection fraction is the proportion of that volume ejected with each beat, influenced by contractility and afterload. Cardiac output is the total blood flow per minute, calculated from heart rate times stroke volume, not the pressure the ventricle must overcome.

Afterload is the force or pressure the ventricle must overcome to eject blood. It reflects the pressure the ventricle must push against, primarily the aortic (or pulmonary) arterial pressure and systemic vascular resistance. When afterload is high, the ventricle has to work harder to open the aortic valve and propel blood forward, which can reduce stroke volume if contractility doesn’t compensate.

End diastolic volume is the amount of blood in the ventricle at the end of filling (preload). Ejection fraction is the proportion of that volume ejected with each beat, influenced by contractility and afterload. Cardiac output is the total blood flow per minute, calculated from heart rate times stroke volume, not the pressure the ventricle must overcome.