Ventricle (heart)

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Structure diagram of the human heart from an anterior view. The larger cavities are the ventricles.

In the heart, a ventricle is one of two large chambers that collect and expel blood received from an atrium towards the peripheral beds within the body and lungs. The atrium (an adjacent/upper heart chamber that is smaller than a ventricle) primes the Pump. Interventricular means between two or more ventricles (for example the interventricular septum), while intraventricular means within one ventricle (for example an intraventricular block).

In a four-chambered heart, such as that in humans, there are two ventricles that operate in a double circulatory system: the right ventricle pumps blood into the pulmonary circulation to the lungs, and the left ventricle pumps blood into the systemic circulation through the aorta.

Structure[edit]

Main articles: Left ventricle and Right ventricle

Ventricles have thicker walls than atria and generate higher blood pressures. The physiologic load on the ventricles requiring pumping of blood throughout the body and lungs is much greater than the pressure generated by the atria to fill the ventricles. Further, the left ventricle has thicker walls than the right because it needs to pump blood to most of the body while the right ventricle fills only the lungs.

The mass of the left ventricle, as estimated by magnetic resonance imaging, averages 143 g ± 38.4 g, with a range of 87––224 g.[1]

Function[edit]

During systole, the ventricles contract, pumping blood through the body. During diastole, the ventricles relax and fill with blood again.

Volumes[edit]

In cardiology, the performance of the ventricles are measured with several volumetric parameters, including end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV)and ejection fraction (Ef).

Wiggers diagram of various events of a cardiac cycle, showing left ventricular volume as a red trace.
Measure Typical value Normal range
end-diastolic volume (EDV) 120 mL[2][non-primary source needed] 65–240 mL[2][non-primary source needed]
end-systolic volume (ESV) 50 mL[2][non-primary source needed] 16–143 mL[2][non-primary source needed]
stroke volume (SV) 70 mL 55–100 mL
ejection fraction (Ef) 58% 55–70%[3]
heart rate (HR) 75 bpm 60–100 bpm[4]
cardiac output (CO)oo 5.25 L/minute 4.0–8.0 L/min[5]

Dimensions[edit]

The heart and its performance are also commonly measured in terms of dimensions, which in this case means one-dimensional distances, usually measured in millimeters. This is not as informative as volumes, but may be much easier to estimate with e.g. M-Mode echocardiography[6] or with sonomicrometry (mostly used for animal model research). Optimally, it is specified with which plane the distance is measured in, e.g. the dimension of the longitudinal plane.[7]

Dimension Abbreviation Definition Normally
End-diastolic dimension EDD The diameter across a ventricle at the end of diastole, if not else specified then usually referring to the transverse[8] (left-to-right) internal (luminal) distance, excluding thickness of walls, although it can also be measured as the external distance.
Left ventricular end-diastolic dimension
LVEDD or sometimes LVDD The end-diastolic dimension of the left ventricle. 48 mm,[9]
Range 36 – 56 mm[10]
Right ventricular end-diastolic dimension
RVEDD or sometimes RVDD The end-diastolic dimension of the right ventricle. Range 10 – 26 mm[10]
End-systolic dimension ESD ESD is similar to the end-diastolic dimension, but is measured at the end of systole (after the ventricles have pumped out blood) rather than at the end of diastole.
Left ventricular end-systolic dimension
LVESD or sometimes LVSD The end-systolic dimension of the left ventricle. Range 20 – 40 mm[10]
Right ventricular end-systolic dimension
RVESD or sometimes RVSD The end-systolic dimension of the right ventricle. Range 10 – 26 mm[10]
Interventricular septal end diastolic dimension IVSd The thickness of the interventricular septum. 8.3 mm,[9]
Range 7 – 11 mm[10]
Left ventricular end diastolic posterior wall dimension LVPWd The thickness of the posterior left ventricular wall. 8.3 mm,[9]
Range 7 – 11 mm[10]
Left atrial dimension LA Range 24 – 40 mm[10]

Fractional shortening (FS) is the fraction of any diastolic dimension that is lost in systole. When referring to endocardial luminal distances, it is EDD minus ESD divided by EDD (times 100 when measured in percentage).[11] Normal values may differ somewhat dependent on which anatomical plane is used to measure the distances. Normal range is 25-45%, Mild is 20-25%, Moderate is 15-20%, and Severe is <15%.[12] Cardiology Diagnostic Tests Midwall fractional shortening may also be used to measure diastolic/systolic changes for inter-ventricular septal dimensions[13] and posterior wall dimensions. However, both endocardial and midwall fractional shortening are dependent on myocardial wall thickness, and thereby dependent on long-axis function.[14] By comparison, a measure of short-axis function termed epicardial volume change (EVC) is independent of myocardial wall thickness and represents isolated short-axis function.[14]

Clinical significance[edit]

See also[edit]

References[edit]

  1. ^ 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): 765–773. doi:10.2214/ajr.184.3.01840765. 
  2. ^ 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): 765–773. 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.
  3. ^ O'Connor, Simon (2009). Examination Medicine (The Examination). Edinburgh: Churchill Livingstone. p. 41. ISBN 0-7295-3911-3. 
  4. ^ Normal ranges for heart rate are among the narrowest limits between bradycardia and tachycardia. See the Bradycardia and Tachycardia articles for more detailed limits.
  5. ^ Edwards Lifesciences LLC > Normal Hemodynamic Parameters – Adult 2009
  6. ^ van Dam I, van Zwieten G, Vogel JA, Meijler FL (1980). "Left ventricular (diastolic) dimensions and relaxation in patients with atrial fibrillation". Eur. Heart J. Suppl A: 149–56. PMID 7274225. 
  7. ^ [1] Longitudinal fractional shortening and its relation to diastolic cardiac function. Journal: Journal of Medical Ultrasonics Publisher: Springer Japan ISSN: 1346-4523 (Print) 1613-2254 (Online) Issue: volume 35, Number 3 / September, 2008 Category: Original Article doi:10.1007/s10396-008-0176-0 Pages: 113-118 Subject Collection: Medicine SpringerLink Date: Friday, September 19, 2008
  8. ^ Grimsgaard S, Bønaa KH, Hansen JB, Myhre ES (July 1998). "Effects of highly purified eicosapentaenoic acid and docosahexaenoic acid on hemodynamics in humans". Am. J. Clin. Nutr. 68 (1): 52–9. PMID 9665096. 
  9. ^ a b c Basavarajaiah S, Wilson M, Naghavi R, Whyte G, Turner M, Sharma S (November 2007). "Physiological upper limits of left ventricular dimensions in highly trained junior tennis players". Br J Sports Med 41 (11): 784–8. doi:10.1136/bjsm.2006.033993. PMID 17957014. 
  10. ^ a b c d e f g Page 41 in: O'Connor, Simon (2009). Examination Medicine (The Examination). Edinburgh: Churchill Livingstone. ISBN 0-7295-3911-3. 
  11. ^ chfpatients.com > Fractional Shortening (FS) Retrieved on April 7, 2010
  12. ^ https://www.stanford.edu/group/ccm_echocardio/cgi-bin/mediawiki/index.php/Left_ventricle_size
  13. ^ de Simone G, Devereux RB, Roman MJ, et al. (May 1994). "Assessment of left ventricular function by the midwall fractional shortening/end-systolic stress relation in human hypertension". J. Am. Coll. Cardiol. 23 (6): 1444–51. doi:10.1016/0735-1097(94)90390-5. PMID 8176105. 
  14. ^ a b Ugander M, Carlsson M, Arheden H (Feb 2010). "Short-axis epicardial volume change is a measure of cardiac left ventricular short-axis function, which is independent of myocardial wall thickness". Am J Physiol Heart Circ Physiol 298 (2): H530–5. doi:10.1152/ajpheart.00153.2009. PMID 19933422.