Clinical Physiology of Circulation

Chief Editor

Leo A. Bockeria, MD, PhD, DSc, Professor, Academician of Russian Academy of Sciences, President of Bakoulev National Medical Research Center for Cardiovascular Surgery


Modeling of normal heart valve development in children

Authors: L.A. Bockeria 1, O.A. Makhachev 1, V.V. Golubkov 2,   M.S. Panova 1, T.Yu. Filippkina 1, B.E. Narsiya 1

Company:
1 A.N. Bakoulev Scientific Center for Cardiovascular Surgery of the Russian Academy of Medical Sciences, Rublevskoe shosse, 135, Moscow, 121552, Russia; 

  2 Institute of Systemic Analysis of the Russian Academy of Sciences, pr. 60-letiya Oktyabrya, 9, Moscow, 117312, Russia

Link: Clinical Physiology of Blood Circulaiton. 2013; (): -

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Abstract

Objective of the research is to study the process of heart valves development in growing children's bodies using mathematical modeling. Material and methods. The data obtained from morphometric study of 1447 unfixed preparations of normal hearts of the children in the age group between birth and 15 years was used as research material. Circumferences were taken as measurable indicators of the development of heart valves, and body growth and development were assessed using height (body length measurements) and age. Based on developmental systems theory mathematical models showing the correlation between the circumferences of heart valves, age and height, as well as between height and age of children of both genders were constructed. The constructed models were used to perform analysis of heart valve development. Results. It was shown that the established age-related models of the correlation between the dynamics of development of cardiac valve circumferences and body growth for both genders were very effective in describing the statistical data (in them the adequacy criterion R2 value is higher than 0.98). It was determined that at the age of ~20 months (bifurcation point), regardless of the type of the heart valve and child's gender, qualitative changes in the pattern of correlation between the circumferences of heart valves and body growth and age occur: in the age range from 0 to the age of bifurcation the rate of the average valve growth in size was 3.5 times, and of the height – 4.5 times more intensive than in older children. Three age-related time periods in heart valve development and growth were established. In the first period, from 0 to tmax the valve growth outpaces somatic growth with indexed circumference reaching its maximum value at tmax age. In the second period, from tmax to tpr values (tmax < tpr), on the contrary, somatic growth outpaces valve growth. In the third period (t > tpr) valve development and somatic growth are proportional. The duration of the first period doesn't depend on gender and it is longer for aortic valve compared to three other heart valves (an average value for boys and girls is 7.12 months compared to 4.87; 5.16 and 4.94 months). The duration of the second period for left side of the heart is longer than for the right side of the heart (111.70; 122.53 versus 83.20; 80.73 in boys and 93.24; 117.31 versus 65.77; 71.86 in girls). The second period in the right-sided valves ends around 6 years of age on the average, and in aortic and mitral valves – by 8–10 years of age respectively. Conclusion. Universal age-related models that are able to describe the dynamics of body growth and development of the circumferences of heart valves with a high degree of adequacy were created. Three time periods in the concurrent processes of the development of heart valves and body growth are outlined – when development of valves outpaces the body growth, somatic growth outpaces valve growth and the period when valves and body growth is proportional. The growth of aortic valve was more continuous in the first period. The second period was characterized by more continuous development of valves of the left side of the heart in comparison with the valves of the right side of the heart, it has physiological significance related to the function of the left side of the heart and of the left ventricle in particular.

References

1. West G.B., Brown J.H. The origin of allometric scaling laws in biology from genoms to ecosystems: towards a quantitative unifying theory of biological structure and organization. Journal of Experimental Biology. 2005; 208: 1575–92. 2. Gaiton J. Hystory of the Concept of Allometry. Amer. Zool. 2000; 40: 748–58. 3. Huxley J.S. Constant differential growth-ratios and their significance. Nature. 1924; 11(4): 895–6. 4. Malcolm D.D., Burns T.L., Mahoney L.T., Lauer R.M. Factors affecting left ventricular mass in childhood: the muscatine study. Pediatrics. 1993; 92: 703–9. 5. Batterham A.M., George K.P., Mullineaux D.R. Allometric scaling of left ventricular mass by body dimensions in males and females. Med. Sci. Sports Exerc. 1997; 29 (2): 181–6. 6. Batterham A.M., George K.P. Modeling the influence of body size and composition on M-mode echocardiographic dimensions. Am. J. Physiol. Heart Circ. Physiol. 1998; 274: H701–H708. 7. George K., Sharma S., Batterham A., Whyte G., McKenna W. Allometric analysis of the association between cardiac dimensions and body size variables in 464 junior athletes. Clinical Science. 2001; 100: 47–54. 8. De Simone G., Devereux R.B., Daniels S.R., Koren M.J., Meyer R.A., Laragh J.H. Effect of growth on variability of left ventricular mass: assessment of allometric signals in adults and children and their capacity to predict cardiovascular risk. JACC. 1995; 25 (5): 1056–62. 9. Sluysmans Th., Colan S.D. Theoretical and empirical derivation of cardiovascular allometric relationships in children. J. Appl. Physiol. 2005; 99: 445–57. 10. Devereux R.B., Lutas E.M., Casale P.N., Kligfield P., Eisenberg R.R., Hammond I.W. et al. Standardization of M-mode echocardiographic left ventricular anatomic measurements. JACC. 1984; 4 (6): 1222–30. 11. Ichida F., Aubert A., Denef B., Dumoulin M., Van der Hau-waert L.G. Cross sectional echocardiographic assessment of great artery diameters in infants and children. Br. Heart J. 1987; 58: 627–34. 12. Lappen Rh.S., Riggs Th.W., Lapin G.D., Paul M.H., Muster A.J. Two-dimensional echocardiographic measurement of right pulmonary artery diameneter in infants and children. JACC. 1983; 2 (1): 121–6. 13. Batterham A.M., George K.P., Whyte G., Sharma S., McKenna W. Scaling cardiac structural data by body dimensions: a review of theory, practice, and problems. Int. J. Sports Med. 1999; 20 (8): 495–502. 14. Liao Y., Cooper R.S., Durazo-Arvizu R., Mensah G.A., Ghali J.K. Prediction of mortality risk by different methods of indexation for left ventricular mass. JACC. 1997; 29 (3): 641–7. 15. Gutgesell H.P., Paquet M., Duff D.F., McNamara D.G. Evaluation of left ventricular size and function by echocardiography. Results in normal children. Circulation. 1977; 56 (3): 457–62. 16. Nielan T.G., Pradhan A.D., King M.E., Weyman A.E. Derivation of a size-independent variable for scaling of cardiac dimensions in a normal paediatric population. Eur. J. Echocardiography. 2009; 10: 50–5. 17. Daniels S.R., Kimball Th.R., Morrison J.A., Khoury Ph., Meyer R.A. Indexing left ventricular mass to account for differences in body size in children and adolescents without cardiovascular disease. Am. J. Cardiol. 1995; 76: 699–701. 18. Nidorf S.M., Picard M.H., Triulzi M.O., Thomas J.D., Newell J., King M.E., Weyman A.E. New perspectives in the assessment of cardiac chamber dimensions during development and adulhood. JACC. 1992; 19 (5): 983–8. 19. Gutgesell H.P., Rembold Ch.M. Growth of the human heart relative to body surface area. Am. J. Cardiol. 1990; 65: 662–8. 20. Lauer M.S., Anderson K.M., Larson M.G., Levy D. A new method for indexing left ventricular mass for differences in body size. Am. J. Cardiol. 1994; 74: 487–49. 21. Schulz D.M., Giordano D.A. Hearts in infants and children. Arch. Pathol. 1962; 74: 464–71. 22. Вентцель Е.С. Теория вероятностей. М.: Государственное издательство физико-математической литературы; 1962. 23. Глинский В.В., Игонин В.Г. Статистический анализ. М.: Филинъ; 1998.

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