<prompt> Preload measures?End systolic volumeEnd diastolic volumePeripheral resistanceStroke volume  <response>: ANSWER: B End diastolic volumeREF: Guytons physiology 22nd edition page 111, 28cardiology29For cardiac contraction, the preload is usually considered to be the end-diastolic pressure when the ventricle has become filledQuantitatively, preload can be calculated asLV EDT . LV EDR2hWhere LVEDP Left ventricular end diastolic pressure, LVEDR Left ventricular end diastolic radius at the ventricle s midpoint, and h thickness of the ventricle. This calculation is based on the Law of Laplace. 