Eur J Cardiothorac Surg 2005;28:869-870
© 2005 Elsevier Science NL
Editorial comment
Reinforcing the anastomotic cuff in aortic dissection
Bettina Marty
*
Department of Cardiovascular Surgery, University Hospital CHUV, Rue de Bugnon 46, 1011 Lausanne, Switzerland
* Tel.: +41 21 314 2596; fax: +41 21 314 2278. (Email: martyb{at}hopcantfr.ch).
The dissected aorta is prone to anastomotic complications such as bleeding and dehiscence. The aortic wall is friable due to medial cystic necrosis, fragmentation of the elastic lamellae, focal fibrosis, and the dissecting hematoma between the middle and the outer third of the media. Yet the adventitial layer remains intact [1]. Current methods to reinforce the aorta make use of Teflon or Dacron strips and biologic glue. Resulting possible disadvantages are difficulties to accurately localize anastomotic bleeding and a bulky anastomosis predisposing to luminal narrowing and pressure decrease. Therefore, reference surgeons recommended neither to use prosthetic reinforcement nor the inclusion technique [2].
Tanaka et al. present the formerly described adventitial inversion technique for the repair of acute type A aortic dissection with respect to closure of the false lumen [3,4]. The dissected flap is trimmed back 1 cm distal to the resection line. The redundant layer of adventitia including the adherent outer third of media is folded into the lumen and tacked down. Thereby the resulting anastomotic cuff consists of two adventitial and external elastic lamina layers "sandwiching" two thirds of the friable media. A tough but soft cuff for anastomosis is created, with a low profile enabling accurate suturing and precise localization of bleeding points. Besides, the cuff has a desirable sealing effect by activation of the extrinsic coagulation pathway via exposed adventitial collagen and tissue factor [5]. The latter is a cell membrane bound glycoprotein, and upon exposure to blood, binds to factor VII. The tissue factor—factor VIIa complex activates factor X and thence generates thrombin.
This technique carries the potential risk of thrombus formation at the adventitial anastomotic rim with subsequent embolization. In small caliber anastomoses with intima–adventitia apposition, thrombus deposition has been observed only at the adventitial rim not causing luminal narrowing [6]. It is unlikely that in a high-flow system such as the aorta, protruding thrombus is developing at the anastomotic site. However, surface irregularities are certainly filled up by thrombus that becomes subsequently replaced by neointima during anastomotic remodeling [7]. The embolic potential is probably very low.
The proposed technique ensures that the false lumen is excluded from antegrade flow at the anastomotic level. Although important, Tanaka et al. show that other means are equally crucial in contributing to the closure of the intimal tear at the entry site. They underscore the importance of exploration of the aortic arch including replacement whenever necessary and avoidance of distal clamping to prevent damage to the aorta beyond the anastomosis.
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References
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- Cotran RS, Kumar V, Collins T, Robbins SL. Robbins pathologic basis of disease. 6th ed.. Elsevier Science Health Science; 1998.
- Svensson LG, Crawford ES, Hess KR, Coselli JS, Safi HJ. Dissection of the aorta and dissecting aortic aneurysms. Improving early and long-term surgical results. Circulation 1990;82(Suppl. IV):IV24-IV38.
- Floten HS, Ravichandran PS, Furnary AP, Gately HL, Starr A. Adventitial inversion technique in repair of aortic dissection. Ann Thorac Surg 1995;59:771-772.[Abstract/Free Full Text]
- Garcia-Rinaldi R, Carballido J, Mojica J, Soltero ER, Curcic S, Barcelo J, Porro PR. Surgical treatment of aortic dissections: initial experience with the adventitial inversion technique. Ann Thorac Surg 1998;65:1255-1259.[Abstract/Free Full Text]
- Dumanian GA, Heil BV, Khouri RK, Hing C, Labadie K, Wun T-C, Johnson PC. Tissue factor and its inhibition at the human microvascular anastomosis. J Surg Res 1996;60:263-269.[Medline]
- Heijmen RH, Gründeman PF, Borst C. Intima–adventitia apposition in end-to-side arterial anastomosis: an experimental study in the pig. Ann Thorac Surg 1998;65:705-711.[Abstract/Free Full Text]
- Marty B, Maeder B, Gallino A, Mucciolo A, von Segesser LK. Does large oversizing of self-expandable endoprostheses compensate for aortic growth?. J Vasc Surg 2003;38:1368-1375.[Medline]
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References