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The right ventricular end-diastolic volume (RVEDV) ranges between 100 and 160 mL. [5] The right ventricular end-diastolic volume index (RVEDVI) is calculated by RVEDV/BSA and ranges between 60 and 100 mL/m 2. [5]
In a healthy 70-kilogram (150 lb) man, the stroke volume is approximately 70 mL, and the left ventricular end-diastolic volume (EDV) is approximately 120 mL, giving an estimated ejection fraction of 70 ⁄ 120, or 0.58 (58%).
Since sarcomere length cannot be determined in the intact heart, other indices of preload such as ventricular end-diastolic volume or pressure are used. As an example, preload increases when venous return is increased. This is because the end-diastolic pressure and volume of the ventricle are increased, which stretches the sarcomeres.
Diastolic dysfunction is associated with a reduced compliance, or increased stiffness, of the ventricle wall. This reduced compliance results in an inadequate filling of the ventricle and a decrease in the end-diastolic volume. The decreased end-diastolic volume then leads to a reduction in stroke volume because of the Frank-Starling mechanism. [1]
Stroke volume is an important determinant of cardiac output, which is the product of stroke volume and heart rate, and is also used to calculate ejection fraction, which is stroke volume divided by end-diastolic volume. Because stroke volume decreases in certain conditions and disease states, stroke volume itself correlates with cardiac function.
Preload is related to the ventricular end-diastolic volume; a higher end-diastolic volume implies a higher preload. However, the relationship is not simple because of the restriction of the term preload to single myocytes. Preload can still be approximated by the inexpensive echocardiographic measurement end-diastolic volume or EDV.
Stroke volume (= end-diastolic volume − end-systolic volume) Ejection fraction (= stroke volume / end-diastolic volume) Cardiac output is mathematically ` to systole [clarification needed] Inotropic, chronotropic, and dromotropic states; Cardiac input (= heart rate * suction volume Can be calculated by inverting terms in Fick principle)
For example, the end-diastolic pressure-volume relationship (EDPVR) and end-systolic pressure-volume relationship (ESPVR) are derived from series of loops obtained by slowly inflating a balloon to occlude the inferior vena cava, a procedure that reduces cardiac preload. Calculation of EDPVR and ESPVR