Histologic examination of the clipped internal thoracic artery by transmission electron microscope in patients undergoing coronary artery bypass grafting

Cenap Ozkara

Department of the Cardiovascular Surgery, Corlu Sifa Hospital, Tekirdag, Turkey.

DOI: 10.4236/wjcd.2012.23035                

Abstract

Object?ves: As we known that the internal thoracic artery (ITA) has an excellent patency rate in coronary artery bypass grafting (CABG). However, early graft failure due to occlusion and spasm is still the major problem after coronary artery bypass surgery. We examined histopathologic findings of the clipped internal thoracic artery (ITA) in patients undergoing CABG using transmission electron microscope (TEM). Methods: To investigate the histopathololojic ITA examination, 60 patients were randomly selected. The ITA was harvested in a standart fashion with the use of low voltage electrocotery and its distal end was cut prior to bifurcation and clipped. Just before the ITA anastomosis 1 mm lenght of ITA ring was cut and saved in 2.5% Glutaraldehide solution for fixation and examination of transmission electron microscope (TEM). One blinded anatomopatholog examined all specimens and described the endothelial integrity according to the score system proposed by Fischlein et al. Results: In ten cases (17.5%) different degree of histopathologic findings (endothelial cells, intercellular and intracellular organels and adventitia) were recorded The most important histopatholojic findings of ITA were as follows: endothelial vacuolisation, intimal thickening and/or intimal seperation, suben-dothelial edema, swallowing of cytoplasma and mito-condria. Conclusion: Our results showed that the endothelial pathology is high when the ITA clipped. Unfortunataly, because our study did not include the non-clipped ITA we have not concluded the comparison or statistical results. In our opinion, for absolute definition of the effects of the clipping the ITA it should be planned the comparative results between the clipped and non-clipped ITA histologic examinations.

Keywords

Internal Thoracic Artery; ITA Clipping; Endothelia Pathology

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Thatte, H.S. and Khuri, S.F. (2001) The coronary artery bypass conduit: I. Intraoperative endothelial injury and its implication on graft patency. Annals of Thoracic Surgery, 72, S2245-S2252. doi:10.1016/S0003-4975(01)03272-6
[2]	Verrier, E.D. and Boyle, E.M. Jr. (1996) Endothelial cell injury in cardiovascular surgery. Annals of Thoracic Surgery, 62, 915-922. doi:10.1016/S0003-4975(96)00528-0
[3]	Fischlein, T., Schütz, A., Uhlig, A., Frey, R., Krupa, W., Babic, R., Thiery, J. and Reichart, B. (1994) Integrity and viability of homograft valves. European Journal Cardio- Thoracic Surgery, 8, 425-430. doi:10.1016/1010-7940(94)90084-1
[4]	Loop, F.D., Lytle, B.W., Cosgrove, D.M., et al. (1986) Influence of the internal-mammary artery graft on 10- year survival and other cardiac events. The New England Journal of Medicine, 314, 1-6. doi:10.1056/NEJM198601023140101
[5]	Grapow, M.T.R., Preiss, M., Bernet, F. and Zerkowski, H.R. (2002) Surgical treatment in end-stage coronary artery disease. Cardiovascular Medicine, 5, 190-197.
[6]	Sarabu, M.R., McClung, J.A., Fass, A. and Reed, G.E. (1987) Early postoperative spasmin left internal mammary artery bypass grafts. Annals of Thoracic Surgery, 44, 199-200. doi:10.1016/S0003-4975(10)62041-3
[7]	Shelton, M.E., Forman, M.B., Virmani, R., Bajaj, A., Stoney, W.S. and Atkinson, J.B. (1988) A comparison of morphologic and angiographic findings in long-term internal mammary artery and saphenous vein bypass grafts. Journal of the American College of Cardiology, 11, 297-307. doi:10.1055/s-2005-865827
[8]	Grapow, M.T.R., Konerding, M.A., Müller-Schweinitzer, E., Bernet, F., Matt, P., Reineke, D.C. and Zerkowski, H.- R. (2005) Protecting the endothelial integrity of internal thoracic arteries. The Thoracic and Cardiovascular Surgeon, 53, 352-357.
[9]	Luscher, T.F. and Noll, G. (1995) The pathogenesis of cardiovascular disease: Role of the endothelium as a target and mediator. Atherosclerosis, 118, 81-90. doi:10.1016/0021-9150(95)90076-4
[10]	Moncada, S. and Higgs, A. (1993) The L-arginine-nitric oxide pathway. The New England Journal of Medicine, 329, 2002-2012. doi:10.1056/NEJM199312303292706
[11]	Stary, H.C. (1992) Composition and classification of human atherosclerotic lesions. Virchows Archiv A, Patho- logical Anatomy and Histopathology, 421, 277-290. doi:10.1007/BF01660974
[12]	Higami, T., Maruo, A., Yamashita, T., Shida, T. and Ogawa, K. (2000) Histologic and physiologic evaluation of skeletonized internal thoracic artery harvesting with an ultrasonic scalpel. Journal of Thoracic and Cardiovascular Surgery, 120, 1142-1147. doi:10.1067/mtc.2000.110189
[13]	Grapow, M.T., Kern, T., Reineke, D.C., Brett, W., Bernet, F., Rueter, F., Muller-Schweinitzer, E. and Zerkowski, H.R. (2003) Improved endothelial function after a modified harvesting technique of the internal thoracic artery. European Journal Cardio-Thoracic Surgery, 23, 956-960. doi:10.1016/S1010-7940(03)00122-2