Omental Transposition Flap for Salvage of Ventricular Assist Devices

D Sajjadian and colleagues have presented their experience with a very difficult problem, that is, the management of ventricular assist device–related infections. With the demand for organ transplants and the relative shortage of donors, the ventricular assist device has become a bridge to cardiac transplantation. Technological advancements in the device and anticoagulants have improved the early problems of thrombogenicity and embolism. The current significant problem remains infection, which the authors report occurs in up to 66 percent of patients. In this series, 76 ventricular assist devices were placed from 2000 to 2004 at the University of Pittsburgh. Of these, 11 patients (14 percent) developed infection. Infections were caused by a variety of microorganisms. Of the 11 patients with ventricular assist device infection, two died, four had the device explanted, and five were salvaged with a pedicled omental flap and bilateral pectoralis major advancement flaps. At the time the article was written, the outcome of the five salvaged patients included two successful transplants, two resolved infections with ventricular assist devices in place in patients still awaiting transplantation, and one late death from an unknown cause. Dealing with infections related to prosthetic devices generally results in the need for device removal. Although an infected breast implant after breast reconstruction can occasionally be salvaged with a flap, device removal and later replacement is more typical. This generally is not a life-threatening situation. Infected peripheral vascular grafts can be more problematic. Again, these can occasionally be salvaged with a muscle flap but, in general, device removal is needed, necessitating alternative means of limb revascularization (autologous tissue grafts and/or bypass away from the zone of infection). Infected peripheral vascular grafts can be limb or even life threatening. Infection of a ventricular assist device represents a life-threatening situation from the standpoint of the central infected prosthetic device or loss of the assist in cardiac function if the device is removed. Therefore, aggressive management of this condition is mandatory. As noted by the authors, there are situations when the myocardium has recovered sufficiently from an ischemic insult that the device can be removed without consequence. However, when this is not the case, alternative solutions are needed. The use of local flaps to bring healthy tissue into the zone of infection has precedence. The goals are to eliminate as much infected material as possible with debridement and irrigation, obliterate dead space with healthy soft tissue, and administer systemic antibiotic therapy. As the authors point out, the rectus flap, although potentially useful, is not ideal in this setting. First, the device is often implanted into the abdominal wall. Second, the superior epigastric vascular pedicle may not be available because of the use of the internal mammary vessels for coronary revascularization. The omentum in this setting is ideal. It can provide a large amount of well-vascularized tissue based on the gastroepiploic vessels. It can easily be placed into the mediastinum and, because of its pliability, can be placed in such a way as to completely envelop the ventricular assist device. The flap is quickly harvested through an extension of the preexisting sternal incision and does not require microsurgical expertise. Although pedicled pectoralis major flaps are very useful in the setting of sternal wound infection, they lack the pliability and surface area needed to envelop the device. In this series, the authors have augmented the omentum flap with the use of pectoralis major flaps to eliminate all dead space and allow for tension-free chest wall closure. Whether or not the omentum alone would have sufficed is not known because the authors elected to perform the pectoralis advancement in each case. The authors are to be commended on the use of omental and pectoralis flaps to effectively mange this difficult problem in a compromised patient population. It would be of interest to know, as their experience grows, whether the omentum alone would be sufficient in the setting of adequate skin coverage.