Morphometric Study of Epicardium and Myocardium Thickness in Adult Human Hearts

Noor Abbas Ramadan ^1*, Elham Majeed Mahmood ¹, Saad Ahmed Mohammed ¹

This study demonstrated the heart layer morphology, providing insights into cardiac anatomy, age, and gender influences, aiding clinical diagnosis and treatment.

Abstract

Background: Understanding the structural dynamics of the heart across diverse demographics sheds light on cardiac function, pathology, and therapeutic interventions. This study aimed to determine the histological and morphometric features of the heart's layers, particularly the left atrium (LA) and left ventricle. Methods: Heart samples were obtained from 32 cadavers, comprising both male and female individuals, across four age groups (≤ 29, 30-39, 40-49, and ≥50). These samples were sourced from the forensic center of Azadi Teaching Hospital in Kirkuk city between March 2023 and August 2023. Results: Morphometric analysis revealed that the mean thickness of the epicardium layer varied among the four age groups of the left atrium (LA), ranging from a minimum mean of 103.5 μm in females to a maximum mean of 928.5 μm in males. Similarly, the mean thickness of the myocardium layer of the LA ranged from a minimum mean of 1649 μm in females to a maximum mean of 3176 μm in males. In the left ventricle (LV), the minimum mean thickness of the epicardium layer across the age groups was 217.5 μm in females, while the maximum mean thickness was 1377 μm in males. The minimum mean thickness of the myocardium layer of the LV was 1666 μm in females, and the maximum mean was 4132 μm in males. Conclusion: The study findings indicate that the myocardium layer of both the left atrium and left ventricle is thicker than the epicardium layer in individuals aged between 25 and 57 years. Furthermore, the thickness of both layers was observed to be thinner in females compared to males.

Keywords: Heart anatomy, Epicardium thickness, Myocardium thickness, Gender differences, Age-related changes

References

Almangush, A., Mäkitie, A. A., & Leivo, I. (2021). Back to basics: Hematoxylin and eosin staining is the principal tool for histopathological risk assessment of oral cancer. Oral Oncology, 57.

Almangush, A., Mäkitie, A. A., & Leivo, I. (2021). Back to basics: Hematoxylin and eosin staining is the principal tool for histopathological risk assessment of oral cancer. Oral Oncology.

Al-Sabaawy, H. B., Rahawi, A. M., & Al-Mahmood, S. S. (2021). Standard techniques for formalin-fixed paraffin-embedded tissue: A pathologist’s perspective. Iraqi Journal of Veterinary Sciences, 35, 127-135.

Al-Sabaawy, H. B., Rahawi, A. M., & Al-Mahmood, S. S. (2021). Standard techniques for formalin-fixed paraffin-embedded tissue: A Pathologist’s perspective. Iraqi Journal of Veterinary Sciences, 35, 127-135.

Avazmohamadi, R., Soares, J., Li, D. S., Gorman, R., & Sacks, M. (2019). A contemporary look at biochemical models of the myocardium. National Library of Medicine, 4(21), 417-442.

Bird, S. D., Doevendans, P. A., Van Rooijen, M. A., Brutel de la Riviere, A., Hassink, R., Passier, R., & others. (2003). The human adult cardiomyocyte phenotype. Cardiovascular Research, 58(2), 423-434.

Delgado, L. A., Ernst, A., Castilla, M. G., Bazzaga, D., Peralta, M., Munch, J., & others. (2019). Actin dynamics and Bmp pathway drive apical extrusion of pericardial cell. Cell, 146(3).

Greenbaum, R. A., Yen, H. O. S., Gibson, D. G., Backer, A. E., & Anderson, R. H. (1981). Left ventricle fiber architecture in the human heart. Journal of Anatomy, 45(3), 248-263.

Greenbaum, R. A., Yen, H. O. S., Gibson, D. G., Backer, A. E., & Anderson, R. H. (1981). Left ventricle fiber architecture in the human heart. Journal of Anatomy, 133(3), 248-263.

Hawang, I. C., Park, H. E., & Choi, S. Y. (2017). Epicardial adipose tissue contributes to development of non-calcified coronary plaque: A 5-year computed tomography follow-up study. Journal of Atherosclerosis and Thrombosis, 24(3), 262-274.

Hill, A. J., & Laizzo, P. A. (2015). Comparative cardiac anatomy. Handbook of cardiac anatomy, physiology and devices, 89-114.

Hilll, A. J., & Laizzo, P. A. (2015). Comparative cardiac anatomy. In Handbook of Cardiac Anatomy, Physiology and Devices (pp. 89-114).

Ho, S. Y. (2009). Anatomy and myoarchitecture of the left ventricle wall in normal and in disease. European Journal of Echocardiography, 10(3).

Ho, S. Y. (2009). Anatomy and myoarchitecture of the left ventricle wall in normal and in disease. European Journal of Echocardiography, 10(4), 404-410.

Ho, S. Y., Cabera, J. A., & Sanchez-Quintana, J. (2012). Left atrial anatomy revisited. Advances in Arrhythmia and Electrophysiology, 5(1), 220-228.

Ho, S. Y., Cabera, J. A., & Sanchez-Quintana, J. (2012). Left atrial anatomy revisited. Advance in Arrhythmia and Electrophysiology, 5(1), 220-228.

Legato, M. J., & Leghe, J. K. (2010). Gender and heart: sex-specific differences in the normal myocardial anatomy and physiology. In Principles of Gender-Specific Medicine (pp. 151-161).

Pinali, C., Bennett, J., Davenport, J. B., Caldwell, L., Starbor, L., Trafford, W. A., & Kitmitto, A. (2015). Three-dimensional structure of the intercalated disc reveals plicate domain and gap junction remodeling in heart failure. Biophysical Journal, 108(3), 498-507.

Quijada, P., Trembley, M. A., & Small, E. M. (2020). The role of the epicardium during heart development and repair. Circulation Research, 126, 377-394.

Roth, D. M., Puttagunta, L., & Graf, D. (2022). Histological techniques for sectioning bones of the vertebrate craniofacial skeleton. In Craniofacial Development (pp. 187-200). Humana, New York, NY.

Roth, D. M., Puttagunta, L., & Graf, D. (2022). Histological Techniques for Sectioning Bones of the Vertebrate Craniofacial Skeleton. In Craniofacial Development (pp. 187-200). Humana, New York, NY.

Sampedro-Carrillo, E. A. (2022). Sample preparation and fixation for histology and pathology. Immunohistochemistry and Immunocytochemistry, 33-4.

Sampedro-Carrillo, E. A. (2022). Sample preparation and fixation for histology and pathology. Immunohistochemistry and Immunocytochemistry, 33-4.

St Pierre, S., Peirlinck, M., & Kuhl, E. (2022). Sex matters: a comprehensive comparison of female and male hearts. Frontiers in Physiology, 13, 179-931.

Weinhaus, A. J., & Roberts, K. P. (2005). Anatomy of human heart. Cardiac anatomy, physiology and devices, 51-79.

Weinhaus, A. J., & Roberts, K. P. (2005). Anatomy of the human heart. In Cardiac Anatomy, Physiology and Devices (pp. 51-79).