Y-shaped Muscular Wrapping Technique Avoiding Re-infection of a Replaced Aortic Graft: A Cadaveric Study

Abstract

Replacing an infected prosthetic thoracic aorta graft carries a high re-infection risk. We previously reported two clinical cases successfully treated with a new muscular wrapping technique: latissimus dorsi (LD) muscle flap with a distally based serratus anterior (SA) extension; however, a cadaveric study to prove the regular existence of the distal attachment area was lacking. We tried to establish an appropriate way of elevating the combined muscle flap safely. All of the cadavers were preserved using the Thiel embalming technique to retain flexibility. We checked for the existence of the distal attachment area between the LD and SA. Combined muscle flaps were elevated proximally while identifying the thoracodorsal artery, including the LD and SA branches. After the SA branch was ligated and cut, the SA muscle was manually peeled from the LD muscle with only the distal tight attachment area remaining. Contrast-enhanced computed tomography was performed using a multislice computed tomography system. Six human cadavers (three men, three women: 91 years old, on average) were examined. All six LD and SA combined muscle flaps showed a distal tight attachment area at the level from the seventh rib to the ninth rib. The tip of the SA muscle easily reached the sternum. Contrast-enhanced computed tomography failed to reconfirm the distal vascular flow from the LD to the reverse SA muscle, which we had visualized in a clinical case. We demonstrated the anatomical reliability of the new Y-shaped muscular flaps, which are suitable for preventing re-infection of aortic graft replacement.

Fig. 1.

Cadaveric studies to prove the regular existence of distal continuity between the LD and SA (A). A Y-shaped muscle flap constructed with combined LD muscle and reverse SA muscle (B). Arrows represent the following: yellow, LD muscle; red, SA muscle; blue, distal attachment of the LD and SA.

Fig. 2.

Advancement of the pivot point of the reverse SA muscle is key. The schematic illustration (modified from our previous clinical report) shows the muscular coverage for the replaced thoracic graft.

Fig. 3.

“Posterior-to-anterior” flap elevation maintains the distal attachment of the LD and SA. The reverse SA muscle extends to the aortic arch.