Treatment of Aortic Graft Infection with Autologous Femoral Vein



Treatment of Aortic Graft Infection with Autologous Femoral Vein



J. Gregory Modrall and G. Patrick Clagett


There are no simple solutions to aortic graft infection, but a thoughtful approach to the surgical treatment of this condition minimizes the risk of major morbidity and mortality. No single operation is appropriate for all patients, so a working knowledge of the various options is critical to optimize outcomes.




Options for Reconstruction


The options for aortic reconstruction after graft excision include extra-anatomic bypass and in-situ reconstruction. There are advantages and disadvantages of both approaches (Table 1).




Extraanatomic Reconstruction


Total graft excision with ligation of the aortic stump and extra-anatomic bypass is conceptually appealing because all prosthetic graft material is removed from the infected retroperitoneum. Most commonly, the extra-anatomic bypass consists of unilateral or bilateral bypasses from the axillary artery to the common femoral, profunda femoris, or popliteal arteries. The extra-anatomic bypasses may include a femorofemoral bypass if the groins are free of infection. In stable patients, the two components of the approach may be staged by performing the extra-anatomic bypass at the initial operation, followed by graft excision 1 to 2 days later. If a staged approach is planned, there is a risk of graft thrombosis during the interval between the two operations because of the parallel bypasses.


A disadvantage of aortic ligation with extra-anatomic bypass is the 2% to 5% risk of aortic stump blowout. After excising the infected graft, the aortic stump should be débrided to grossly uninfected tissue and closed in multiple layers. The first layer is a polypropylene horizontal mattress suture, followed by a running baseball suture. The final protective layer is wrapping the stump with vascularized omentum.


Extra-anatomic reconstructions are also plagued by relatively poor patency and a risk of reinfection. The patency of extra-anatomic bypasses is dictated primarily by the quality of infrainguinal outflow. Most patients with aortoiliac occlusive disease and an infected AFB have multilevel arterial occlusive disease and groin sepsis. These patients typically require bilateral axillary–profunda or axillary–popliteal bypasses tunneled laterally to avoid the groin sepsis. Seeger found that the 5-year primary patency rate for axillofemoral bypasses was 64%, but none of the axillopopliteal bypasses in his series were patent beyond 7 months. Systemic anticoagulation has been advocated to prolong patency, but sudden graft thrombosis remains problematic. In addition, cross-contamination and reinfection of the new prosthetic graft occurs in 10% to 20% of cases.


The role of extra-anatomic reconstruction in our practice is currently restricted primarily to patients who are too ill or unstable to undergo a more definitive procedure. Examples include patients with bleeding caused by an aortoenteric fistula.



In-Situ Reconstruction


In-situ aortic reconstruction is an attractive alternative to extra-anatomic bypass because it offers direct revascularization of the lower extremities while avoiding the inferior patency of an extra-anatomic bypass. In-situ reconstruction was initially adopted as an option for treating graft infections caused by relatively low virulence organisms, such as Staphylococcus epidermidis, because it was believed that the risk of reinfection of the prosthetic graft would be minimal. Many centers of expertise now favor this approach for the majority of aortic graft infections. Various conduits have been employed for in situ repair, including autogenous femoropopliteal vein (FPV), human allografts, and redo prosthetic grafting.


Our favored approach for in-situ aortic replacement is FPV. FPV offers the only viable autogenous conduit for in-situ reconstruction. Early attempts to adapt saphenous vein for this purpose were met with universal failure. FPV offers several major advantages for in-situ repair. It is a large-caliber autogenous conduit that is relatively resistant to reinfection and offers excellent long-term patency. FPV also obviates the need for long-term antibiotics postoperatively.


In a report of our experience with FPV in 187 patients, the 30-day mortality was 10% and the procedure-related mortality was 14%. This mortality rate was quite respectable for a disadvantaged patient population in which 35% presented with sepsis or aortoenteric fistulas and the vast majority of patients had advanced multilevel occlusive disease. Moreover, the graft infections in that series included a high proportion of virulent organisms, such as polymicrobial infections (37%), gram-negative species (32%), anaerobes (13%), and fungal organisms (18%). Presumed reinfection of FPV aortic reconstructions occurred in 5% of our grafts, typically manifesting as graft disruption and hemorrhage within 2 weeks of graft implantation. The majority of patients with FPV graft disruption had breakdown of a duodenal repair after FPV reconstruction for aortoenteric fistulas.


We now favor duodenal exclusion if a major duodenal repair is required in conjunction with FPV reconstruction. The alternatives for reconstruction for aortoenteric fistulas are redo in-situ prosthetic grafting or aortic ligation with extra-anatomic bypass. Limb salvage and primary assisted patency were excellent for FPV grafts (89% and 91% at 72 months). Other groups have reported comparable results using FPV.


Several concerns that have been raised about the use of FPV merit discussion. First, there is the perception that FPV harvesting might predispose to venous morbidity. To address this question, we undertook a series of investigations to characterize the early, intermediate, and late venous morbidity associated with removal of the FPVs. Fasciotomy to prevent acute compartment syndrome was performed in 17% of limbs after FPV harvest in our earlier series. Most of these fasciotomies were prophylactic fasciotomies in patients with low ankle-to-brachial indices (ABI < 0.5) or concurrent harvesting of the ipsilateral greater saphenous veins. Our more recent experience indicates that fasciotomy is rarely necessary. The need for fasciotomy has been rare in the absence of these risk factors. Chronic venous insufficiency occurred in 15% of harvested limbs at a mean follow-up of 70 months.


Most venous morbidity consisted of minor limb swelling (CEAP [clinical, etiologic, anatomic, pathophysiologic] classification, C3). In a cohort of more than 350 FPV-harvested legs to date, only one limb developed venous ulceration. Air plethysmography testing of harvesting limbs confirmed that the loss of the deep vein is compensated for over time, because normal venous filling indices were found in 92% of harvested limbs. Indeed, it has been our impression that removal of the FPV is better tolerated with fewer long-term sequelae than recannulation of a femoral–popliteal deep vein thrombosis (DVT). Finally, some surgeons have expressed concern regarding the technical demands and length of the operation for FPV harvesting and reconstruction. The technical demands of the operation are well within the capabilities of any well-trained vascular surgeon. In fact, the most technically demanding components of the operation are the redo aortic and groin dissections, not the FPV harvest.

Related posts:

  1. Technical Aspects of Percutaneous Carotid Angioplasty and Stenting for Arteriosclerotic Disease
  2. In-Situ Treatment of Aortic Graft Infection with Prosthetic Grafts and Allografts
  3. Treatment of Acute Upper Extremity Venous Occlusion
  4. Intraoperative Assessment of the Technical Adequacy of Carotid Endarterectomy

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Aug 25, 2016 | Posted by in CARDIOLOGY | Comments Off on Treatment of Aortic Graft Infection with Autologous Femoral Vein

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