Comparative Morphometric Analysis of Iraqi Sheep (Ovis Aries) and Goats (Capra Hircus) Papillary Muscles, Tendinous Chords, and Os Cardis: Cardiac Anatomy
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Functionally relevant components of the atrioventricular valve complex include papillary muscles and chordae tendineae, which facilitate competent valve closure and unidirectional blood flow. Although comparative information on morphometric and anatomical differences in these structures is key, it is limited in domestic ruminants. For comparison of anatomical position, shape, number, and morphometric sizes of papillary muscles and chordae tendineae in sheep and goats' hearts, and evaluation of their functional implications. Methods: The hearts of eight healthy adult goats and eight healthy adult sheep were included in this research. Individual details of the chordae tendineae and papillary muscles (origin, insertion, length, number, arrangement etc.) were detected and measured through careful dissections. Statistical analysis and interpretation of the morphometric observations were made in the light of the established physiological functions of these structures. Similar observations were made in goats and sheep, with goat hearts having smaller, less prominent papillary muscles and thinner, less organized chordae tendineae when compared with sheep. Papillary muscles were found on the ventricles of both species, with species based differences in number and form. Interspecies differences in the length and diameter of the chordae tendineae with varying patterns of branching and points of insertion (p < 0.05). These morphologic differences suggest adaptations associated with optimal hemodynamics and species-derived cardiac requirements. These structural differences appear to be consistent with functional specialization between the sheep and goats. These observations extend the current knowledge of ruminant cardiac anatomy and may be of value in ruminant veterinary cardiac diagnostics and interventions in the future.
1. Shashank C, Das PK, Sejian V. Veterinary Physiology: Past, Present, and Future Perspective. In: Textbook of Veterinary Physiology. Springer; 2023. p. 3–19.
2. Cooper DK, Ekser B, Tector AJ. Xenotransplantation: The transplantation of organs and tissues between species. Springer; 2012.
3. Lossi L. Anatomical features for an adequate choice of the experimental animal model in biomedicine: III. Ferret, goat, sheep, and horse. Ann Anat. 2022;244:151978.
4. Oriane EA. Simulation of heart loop dynamics in heart morphogenesis [PhD thesis]. Universitat Politècnica de Catalunya; 2023.
5. Clare C. The cardiac system. In: Fundamentals of Anatomy and Physiology. Wiley; 2016.
6. Jett S. Investigations of the Mechanical Properties and Microstructure of the Atrioventricular Heart Valve Leaflets [Thesis]. 2019.
7. Tucker WD, Arora Y, Mahajan K. Anatomy, Blood Vessels. StatPearls [Internet]. 2017.
8. Farrell AP, Jones DR. The Heart. In: Fish Physiology. Elsevier; 2023. p. 91–172.
9. Saxton A, Chaudhry R, Manna B. Anatomy, Thorax, Heart Right Coronary Arteries. StatPearls [Internet]. 2019.
10. Chauhan K, Chauhan RK. Cardiac diseases and their diagnosis methods. In: Image Processing for Automated Diagnosis of Cardiac Diseases. Elsevier; 2021. p. 1–19.
11. Mittal S. Coronary Artery Disease. In: Coronary Heart Disease in Clinical Practice. 2005. p. 107–50.
12. Micheletti A. Congenital heart disease classification, epidemiology, diagnosis, treatment, and outcome. In: Congenital Heart Disease: The Nursing Care Handbook. 2019. p. 1–67.
13. Hammady M, Al-Khafaji F, Saeed M. Detailed Insights into Heart Histology and Cardiomyocyte Molecular Architecture. Alexandria J Sci Technol. 2024;61–78.
14. Nickel R, Schummer A, Seiferle E. The Anatomy of the Domestic Animals. Vol. 1. Berlin: Parey; 1986.
15. Schummer A, Wilkens H, Vollmerhaus B, Habermehl KH. The Circulatory System, the Skin, and the Cutaneous Organs of the Domestic Mammals. Berlin: Parey; 1981.
16. Dellmann HD, Eurell JA. Textbook of Veterinary Histology. 6th ed. Blackwell; 1998.
17. Eurell J, Frappier B. Dellmann’s Textbook of Veterinary Histology. 6th ed. Wiley- Blackwell; 2006.
18. Bacha WJ, Bacha LM. Color Atlas of Veterinary Histology. 3rd ed. Wiley-Blackwell; 2012.
19. Jenkins G, Tortora GJ. Anatomy and Physiology. John Wiley & Sons; 2016.
20. Buckberg G, et al. Cardiac mechanics revisited: the relationship of cardiac architecture to ventricular function. Circulation. 2008;118(24):2571–87.
21. Salazar S, Basso C, Thiene G. Anatomy and pathology of the cardiac conduction system. J Cardiovasc Dev Dis. 2020;7(3):45.
22. Al-Qaisi RK, Saeed MI. Gross morphology and dimensions of papillary muscles in Awassi sheep. Iraqi J Vet Sci. 2022;36(1):123–9.
23. Fawcett DW, McNutt NS. The ultrastructure of the mammalian heart. J Cell Biol. 1969;42(1):1–45.
24. Manasek FJ. Embryonic development of the heart. II. Formation of the atrioventricular valves. J Embryol Exp Morphol. 1970;24(3):271–83.
25. Becker AE, Anderson RH. Morphology of the human atrioventricular junctions. In: Cardiac Anatomy. Springer; 1980. p. 113–29.
26. Tohno Y, Tohno S, Minami T, et al. Differences in collagen fiber composition among chordae tendineae, papillary muscles, and left ventricular walls of the human heart. Okajimas Folia Anat Jpn. 2001;77(3):77–84.
27. Lang RM, Badano LP, Mor-Avi V, et al. Recommendations for cardiac chamber quantification. Eur Heart J Cardiovasc Imaging. 2015;16(3):233–70.
28. Nassar PN, Stollerman J. The moderator band. J Am Coll Cardiol. 2007;49(13):1124.
29. Lombaert H, Peyrat JM, Croisille P, et al. Human atlas of the cardiac fibers: three- dimensional average shape of the myocardial architecture. IEEE Trans Med Imaging. 2012;31(7):1332–40.
30. De Giorgio F, Rainio J, Pascali VL, et al. The structure and function of the cardiac skeleton. Int J Legal Med. 2012;126(4):519–26.
31. Stouffer GA, White JA, Sanyal AJ. Os cordis: Calcification or evolution? Radiographics. 2021;41(1):E24–6.
32. Crick SJ, Sheppard MN, Ho SY, Gebstein L, Anderson RH. Anatomy of the pig heart: comparisons with normal human cardiac structure. J Anat. 1998;193(1):105–19.
33. Hill AJ, Iaizzo PA. Comparative cardiac anatomy. In: Handbook of Cardiac Anatomy, Physiology, and Devices. Springer; 2009. p. 23–38.
34. Vesely I. Heart valve tissue engineering. Circ Res. 2005;97(8):743–55.
35. Johnson SM, et al. Modeling the mitral valve: from structure to function. J Biomech. 2021;118:110245.
