In cardiovascular physiology, end-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole. Because greater EDVs cause greater distention of the ventricle, 'EDV is often used synonymously with preload, which refers to the length of the sarcomeres in cardiac muscle prior to contraction (systole). An increase in EDV increases the preload on the heart and, through the Frank-Starling mechanism of the heart, increases the amount of blood ejected from the ventricle during systole (stroke volume).
Parameters affecting EDV
Because nearly two-thirds of the blood in the systemic circulation is stored in the venous system, end-diastolic volume is closely related to venous compliance.
- Increasing venous compliance elevates the capacitance of the veins, reducing venous return and therefore end-diastolic volume.
- Decreasing venous compliance has the opposite effect. For example, activation of the baroreceptor reflex (occurring, for instance, in acute hemorrhage) causes vasoconstriction, which decreases venous compliance, improves venous return, and therefore increases end-diastolic volume.
The values below are for the left ventricle:
The right ventricular end-diastolic volume (RVEDV) ranges between 100 and 160 mL. The right ventricular end-diastolic volume index (RVEDVI) is calculated by RVEDV/BSA and ranges between 60 and 100 mL/m2.
- ^ a b c d Schlosser, Thomas; Pagonidis, Konstantin; Herborn, Christoph U.; Hunold, Peter; Waltering, Kai-Uwe; Lauenstein, Thomas C.; Barkhausen, Jörg (2005). "Assessment of Left Ventricular Parameters Using 16-MDCT and New Software for Endocardial and Epicardial Border Delineation". Am J Roentgenol 184 (3): 765–73. PMID 15728595. doi:10.2214/ajr.184.3.01840765. Values:
- End-diastolic volume (left ventricular) – average 118 and a range of 68 – 239mL and
- End-systolic volume (left ventricular) – average 50.1 and range, 16 – 143 mL:
- Also, ejection fraction was estimated in this study to be average 59.9% ± 14.4%; range, 18 – 76%, but secondary source (see above) is used in this article instead.
- ^ O'Connor, Simon (2009). Examination Medicine (The Examination). Edinburgh: Churchill Livingstone. p. 41. ISBN 0-7295-3911-3.
- ^ Normal ranges for heart rate are among the narrowest limits between bradycardia and tachycardia. See the Bradycardia and Tachycardia articles for more detailed limits.
- ^ a b c Edwards Lifesciences LLC > Normal Hemodynamic Parameters – Adult 2009