✔ HomeworkClinic.com
✔ Videos.HomeworkClinic.com
✔ Ask questions here: HomeworkClinic.com/Ask
Follow us:
▶ Facebook: / homeworkclinic
▶ Review Us: trustpilot.com/review/homewor...
• Stroke volume is directly correlated with cardiac output-the greater the stroke volume the greater the cardiac output.
• Stroke volume represents the difference in the amount of blood between:
• the volume in the ventricles at the end of diastole (end-diastolic volume EDV);
• the volume after systole (end-systolic volume ESV).
• Normal resting stroke volume is 70 ml.
• Three factors affect stroke volume:
• Preload is the amount of stretch of ventricular muscle before the contraction starts
• Contractility is the forcefulness of ventricular muscle contraction.
• Afterload is the pressure that must be overcome before ventricles can eject blood.
• Preload is the degree of stretch of cardiac muscles cells prior to contraction.
• The amount of stretch is related to the end-diastolic volume[EDV].
• Increased return blood flow from the veins increases end-diastolic volume. Cardiac muscle sarcomeres stretch and lengthen.
• Contraction of the cardiac it muscle sarcomeres during ventricular systole provides the force needed to eject blood from the heart.