Jornal Vascular Brasileiro
https://www.jvascbras.org/article/doi/10.1590/1677-5449.004118
Jornal Vascular Brasileiro
Original Article

Confirmação histológica de aterosclerose devido a dobras e bifurcações das artérias carótidas previstas por modelo hemodinâmico

Histological verification of atherosclerosis due to bends and bifurcations in carotid arteries predicted by hemodynamic model

Rajani Singh, Richard Shane Tubbs

Downloads: 0
Views: 111

Resumo

Contexto: Tortuosidade e bifurcações das artérias carótidas alteram o fluxo sanguíneo, causando aterosclerose. Objetivos: O objetivo do presente estudo foi analisar o efeito de anatomia vascular variante na região cervical sobre o desenvolvimento de aterosclerose via exame microanatômico. Métodos: O efeito do fluxo sanguíneo em dobras e bifurcações anômalas foi observado nas artérias carótidas do lado direito em um cadáver do sexo feminino de 70 anos de idade. Quinze lâminas histológicas foram preparadas a partir das artérias carótidas e interpretadas para confirmar as previsões de aterosclerose. Resultados: O modelo prevê aterosclerose em dobras, bifurcações e artérias de grande calibre. O exame microanatômico revelou a presença de aterosclerose de densidades variáveis nas dobras e bifurcação das artérias carótidas do lado direito, conforme previsto. Aterosclerose também foi detectada na parte reta da artéria carótida comum mais larga. Não foi observada aterosclerose nas artérias carótidas contralaterais. A anatomia vascular carotídea variante consistindo de dobras, bifurcações e artérias mais largas revelou que a tensão de cisalhamento (shear stress) e a velocidade do fluxo sanguíneo são reduzidos nesses pontos anômalos. Conclusões: Anomalias anatômicas tais como dobras e ramificações das artérias carótidas alteram o padrão de irrigação e geram forças biomecânicas que causam fluxo turbulento e reduzem a tensão de cisalhamento e a velocidade do fluxo. Tensão e velocidade menores causam o desenvolvimento de aterosclerose. As lâminas histológicas estabeleceram a presença de aterosclerose nas dobras e bifurcações nas artérias mais largas.

Palavras-chave

tortuosidade; bifurcações; microanatomia; modelo hemodinâmico.

Abstract

Background: Tortuosity and bifurcations in carotid arteries alter the blood flow, causing atherosclerosis. Objectives: The aim of the present study is to analyze the effect of variant vascular anatomy in the cervical region on development of atherosclerosis by microanatomical examination. Methods: The effect of blood flow at anomalous bends and bifurcations was observed in right carotid arteries of a seventy year old female cadaver. Fifteen histological slides were prepared from the carotid arteries and interpreted to verify predictions of atherosclerosis. Results: The model predicts atherosclerosis at bends, bifurcations and large aperture arteries. Microanatomical examination revealed presence of atherosclerosis of varying thickness at the bends and bifurcation in the right carotid arteries, as predicted. Atherosclerosis was also detected in the straight part of the wider common carotid artery. No atherosclerosis was observed in the contralateral carotid arteries. The variant carotid vascular anatomy consisting of bends, bifurcations and wider arteries revealed that the shear stress and velocity of blood flow are reduced at these anomalous sites. Conclusions: Anatomical anomalies such as bends and branching in the carotid arteries alter the irrigation pattern and generate biomechanical forces that cause turbulent flow and reduce shear stress/blood flow velocity. Decreased shear stress and velocity causes development of atherosclerosis. Histological slides established the presence of atherosclerosis at bends and bifurcations and in wider arteries.

Keywords

tortuosity; bifurcations; microanatomy; hemodynamic model.

References

1. Warboys CM, Amini N, de Luca A, Evans PC. The role of blood flow in determining the sites of atherosclerotic plaques. F1000 Med Rep. 2011;3:5. http://dx.doi.org/10.3410/M3-5. PMid:21654925.

2. Ridker PM. On Evolutionary Biology, Inflammation, Infection, and the Causes of Atherosclerosis. Circulation. 2002;105(1):2-4. http://dx.doi.org/10.1161/circ.105.1.2. PMid:11772866.

3. Kinlay S, Libby P, Ganz P. Endothelial function and coronary artery disease. Curr Opin Lipidol. 2001;12(4):383-9. http://dx.doi.org/10.1097/00041433-200108000-00003. PMid:11507322.

4. Luscher TF, Barton M. Biology of the endothelium. Clin Cardiol. 1997;20(11 suppl 2): 3-10.

5. Ross R. Atherosclerosis: an inflammatory disease. N Engl J Med. 1999;340(2):115-26. http://dx.doi.org/10.1056/NEJM199901143400207. PMid:9887164.

6. Taddei S. New evidence for endothelial protection. Medicographia. 2012;34:17-24.

7. Cooke JP. Does ADMA cause endothelial dysfunction? Arterioscler Thromb Vasc Biol. 2000;20(9):2032-7. http://dx.doi.org/10.1161/01.ATV.20.9.2032. PMid:10978245.

8. Ozgur Z, Celik S, Govsa F, Aktug H, Ozgur T. A study of the course of the internal carotid artery in the parapharyngeal space and its clinical importance. Eur Arch Otorhinolaryngol. 2007;264(12):1483-9. http://dx.doi.org/10.1007/s00405-007-0398-6. PMid:17638001.

9. Beigelman R, Izaguirre AM, Robles M, Grana DR, Ambrosio G, Milei J. Are kinking and coiling of carotid artery congenital or acquired? Angiology. 2010;61(1):107-12. http://dx.doi.org/10.1177/0003319709336417. PMid:19755398.

10. Malek AM, Alper SL, Izumo S. Hemodynamic shear stress and its role in atherosclerosis. JAMA. 1999;282(21):2035-42. http://dx.doi.org/10.1001/jama.282.21.2035. PMid:10591386.

11. Radak D, Babic S, Tanaskovic S, et al. Are the carotid kinking and coiling underestimated entities? Vojnosanit Pregl. 2012;69(7):616-9. http://dx.doi.org/10.2298/VSP110722001R. PMid:22838174.

12. Zenteno M, Vinuela F, Moscote-Salazar LR, et al. Clinical implications of internal carotid artery tortuosity,kinking and coiling: a systematic review. Romanian Neurosurgery. XXI. 2014;1:50-9.

13. Caro CG, Fitz-Gerald JM, Schroter RC. Arterial wall shear and distribution of early atheroma in man. Nature. 1969;223(5211):1159-60. http://dx.doi.org/10.1038/2231159a0. PMid:5810692.

14. Ozgur Z, Celik S, Govsa F, Aktug H, Ozgur T. A study of the course of the internal carotid artery in the parapharyngeal space and its clinical importance. Eur Arch Otorhinolaryngol. 2007;264(12):1483-9. http://dx.doi.org/10.1007/s00405-007-0398-6. PMid:17638001.

15. Rosenthal D, Stanton PE Jr, Lamis PA, McClusky D. Surgical correction of the kinked carotid artery. Am J Surg. 1981;141(2):295-6. http://dx.doi.org/10.1016/0002-9610(81)90179-3. PMid:7457753.

16. Higashida RT, Meyers PM, Phatouros CC, Connors JJ 3rd, Barr JD, Sacks D, et al. Reporting standards for carotid artery angioplasty and stent placement. Stroke. 2004;35(5):e112-34. http://dx.doi.org/10.1161/01.STR.0000125713.02090.27. PMid:15105523.

17. Van Damme H, Gillain D, Desiron Q, Detry O, Albert A, Limet R. Kinking of the internal carotid artery: clinical significance and surgical management. Acta Chir Belg. 1996;96(1):15-22. PMid:8629382.

18. Ricciardelli E, Hillel AD, Schwartz AN. Aberrant carotid artery. Presentation in the near midline pharynx. Arch Otolaryngol Head Neck Surg. 1989;115(4):519-22. http://dx.doi.org/10.1001/archotol.1989.01860280117029. PMid:2923696.

19. Timbrell Fisher AG. Sigmoid tortuosity of the internal carotid artery and its relations to tonsil and pharynx. Lancet. 1915;17(4794):128-30. http://dx.doi.org/10.1016/S0140-6736(01)56103-6.

20. Vinnakota S, Nandagiri B, Neelee J. A rare association of curving and looping of internal carotid artery and variation in the branching pattern of external carotid artery –a case report. Int J Biol Med Res. 2011;2:822-3.

5cd17d3d0e88255d06632f8e jvb Articles
Links & Downloads

J Vasc Bras

Share this page
Page Sections