Muscle Flap Transposition for the Management of Intrathoracic Fistulas.

Abstract

Sir: In the article by Asaad et al.,1 the authors describe their experience managing intrathoracic fistulas with muscle flaps. The authors propose a flap-selection algorithm that hinges on whether the latissimus dorsi muscle is intact, however, because of the location of thoracotomy incisions, default to the serratus in most patients. We agree with the authors that the latissimus dorsi flap is better suited for the management of intrathoracic fistulas, but refute the notion that a posterolateral thoracotomy approach precludes the use of latissimus dorsi flaps. In fact, we submit that the routine and preferred use of the latissimus negates the 5 percent rate of additional flaps and the 10 percent rate of flap failure. The authors aptly describe that the latissimus dorsi has more reliable vasculature and natural bulk; but the pedicle anatomy and muscle geometry also provide the potential for circumferential coverage. Although the standard posterolateral approach typically divides the latissimus dorsi, our institutional experience illustrates its use as the workhouse for intrathoracic muscle coverage despite this. We achieve this through collaboration with thoracic surgeons, who begin their portion of the surgery after we have raised the latissimus dorsi muscle. In the instances where this is not possible (i.e., patients with prior thoracotomies), we find that low thoracotomy incisions leave sufficient latissimus dorsi for fistula coverage (Fig. 1).Fig. 1.: (Left) Image displaying the feasibility of raising the latissimus dorsi flap before a thoracotomy incision. (Right) Postoperative computed tomographic scan showing the pedicle of the latissimus dorsi, and the site of the previous fistula with the latissimus dorsi circumferentially wrapped.The authors report a 17 percent intrathoracic complication rate, primarily stemming from either recurrent fistula or the flap. In their series of 238 flaps, all complications occurred in either serratus anterior (6 percent partial flap loss and 2 percent total flap loss) or intercostal flaps (2 percent total flap loss); 21 reported latissimus dorsi flaps had no flap loss. Results from the senior surgeon of this letter (R.S.) supports the low complication rates with latissimus dorsi flaps. Nine patients with intrathoracic complications were all managed with a latissimus dorsi flap despite a posterolateral approach (n = 9). Compared to the nearly 20 percent complication rate provided by the authors, we have observed no flap losses or recurrent fistulas; one patient died because of unrelated complications from a lung transplant with no indication of flap failure at the time of death. Asaad et al. present a significant addition to the sparse literature on intrathoracic fistula management with muscle flaps, although the proposed decision-making algorithm should be further clarified. Retrospective review of our experience identified two key factors for success: (1) anatomical advantages of the latissimus dorsi muscle and (2) coordination with our thoracic surgeons before the procedure. The latissimus dorsi provides additional bulk and the potential for circumferential coverage with a continuous muscle segment, which likely contributes to reduce recurrent fistulas. In addition, we have coordinated with thoracic surgery to allow us to elevate the latissimus dorsi before their portion of the procedure. Combined with a lower thoracotomy incision, patients had sufficient viable latissimus dorsi muscle for coverage in our cohort. We believe the proposed algorithm be reformulated to clarify that division of the latissimus dorsi muscle by means of thoracotomy should not automatically preclude its use, and surgeons should make every attempt to use the latissimus dorsi for the management of intrathoracic fistulas. DISCLOSURE The authors have no financial interest to declare in relation to the content of this communication. Dhivya Srinivasa, M.D.Harsh Patel, B.S.Randolph Sherman, M.D.Plastic and Reconstructive SurgeryCedars-Sinai Medical CenterLos Angeles, Calif.