Preload is affected by the rate of venous return and the venous blood pressure , which are affected by the volume of circulating blood and venous tone .
The preload is related to ventricular end - diastolic volume ,
The higher end - diastolic volume have a higher preload .
<u>Preload is approximated via echocardiographic measurement end diastolic volume or EDV.
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Preload is increased by exercising , or increase in blood pressure and neuroendocrine excitement .
