Total excision and extra-anatomic bypass for aortic graft infection

Thoracic aorta transobturator bipopliteal bypass as eventual durable reconstruction after removal of an infected aortofemoral graft

A 36-year-old man was referred with aortofemoral graft infection and perigraft duodenal erosion. The aortofemoral graft was removed, and bilateral axillo-superficial femoral grafts were constructed. Recurrent failures of these grafts prompted us to convert to a more-durable reconstruction. A straight graft was anastomosed to the lower thoracic aorta, routed retroperitoneally, and attached to an inverted U-shaped bilateral transobturator bypass graft, which was anastomosed to both above-knee popliteal arteries. After 3 years, the patient has remained well and the grafts are patent. This operation represents a durable in-line reconstruction that avoids all previously infected areas after removal of an infected aortofemoral graft.

The superficial femoral vein as arterial substitute in infections of the aortoiliac region

In situ autogenous reconstruction is an alternative therapy for abdominal aortic prosthetic graft infection. We have used the superficial femoral vein (SFV) as an arterial substitute for proximal aortic anastomosis in seven patients. Six patients presented with aortic perigraft infections and one had a mycotic aneurysm of the infrarenal aorta with a primary aortoenteric fistula. There were no intraoperative but two postoperative deaths. During follow-up (mean: 19.8 months), one patient died at 5 months unrelated to his preceding vascular procedures; the others were doing well with patient SFV grafts 6-36 months after autogenous aortoiliac reconstruction. The SFV is a valuable donor vessel for autogenous reconstruction in the management of aortoiliac prosthetic graft infection. We explain both perioperative deaths in our treatment group with respect to the extent of the underlying infection and the virulence of the causative organism.

Management of abdominal aortic prosthetic graft infection requiring emergent treatment

The purpose of this study was to investigate mortality and morbidity rates and long-term outcome of patients who underwent emergency treatment of abdominal aortic prosthetic graft infection. Between January 1984 and December 1993, 18 men aged fifty-nine +/- sixteen years were operated on as an emergency for an acute life-threatening complication of aortic prosthetic graft infection. The grafts had been implanted for abdominal aortic aneurysm in 9 patients and aortoiliac occlusive disease in 9, from one to one hundred seventy months previously. Five (28%) patients presented with a hemorrhagic shock due to a fistula between the vascular reconstruction and the small bowel (4 patients) or the right ureter (1 patient) and 13 (72%) had generalized sepsis. The grafts were always radically explanted. Extraanatomic revascularization procedures included 6 axillopopliteal and 12 axillofemoral bypass grafts. Operative mortality was 39% (7 patients), and 3 (9%) limbs were amputated within thirty days. Two (11%) patients died after seven and twelve months, respectively, of septic complications, and 1 (5%) patient died after six months from an unrelated cause. Eight (73%) patients are still alive at a mean follow-up of fifty +/- thirty-four months, but in 3 the extraanatomic bypass was removed for infection and 5 major amputations were performed. Two-year survival and limb salvage rates were 44% and 50%, respectively. Aortic prosthetic graft infections that require emergent treatment continue to demonstrate high early and late mortality and limb loss rates despite aggressive intervention and limb salvage procedures. Newer methods of managing these complications should continue to be investigated.

Bacterial and clinical criteria relating to the outcome of patients undergoing in situ replacement of infected abdominal aortic grafts

OBJECTIVES

In a retrospective non-randomised study we assessed the outcome after in situ replacement of infected knitted Dacron abdominal aortic grafts in patients without septicaemia or retroperitoneal abscesses. We also assessed whether the specific bacterial infection influenced outcome.

MATERIALS AND METHODS

Over the 5 years studied, 18 patients (9 with perigraft infection and 9 with aortoenteric erosion) underwent in situ replacement of aortofemoral grafts. All patients were haemodynamically stable, none required emergency treatment. Preoperative assessment included CT, MRI, leukocyte-labelled scintigraphy, and bacterial cultures whenever possible. Infected grafts were totally excised and replaced in situ with standard PTFE prostheses. Bacterial diagnosis included intraoperative Gram-staining and postoperative graft cultures. None of the patients had retroperitoneal collections or proximal anastomotic dehiscence. All patients had 6 week intravenous antibiotic therapy.

RESULTS

One patient died of myocardial infarction, and another of haemorrhagic shock from proximal anastomotic dehiscence, accounting for a graft-related mortality of 6%. Dehiscence resulted from a polymicrobial infection. Mean 37 month surveillance showed no amputations and no graft-related infections.

CONCLUSIONS

In clinically and bacteriologically selected patients, total in situ replacement of infected abdominal aortic grafts offers an excellent outcome.

Autogenous aortoiliac/femoral reconstruction from superficial femoral-popliteal veins: feasibility and durability

PURPOSE

Autogenous aortoiliac/femoral reconstruction with superficial femoral-popliteal veins (SFPVs) has been successfully used to treat prosthetic infection and failure, but outcome data are scant. In this prospective, observational study, we hypothesized that (1) replacement of the aortoiliac/femoral system with SFPVs could be performed with perioperative morbidity and mortality rates equal to those of conventional methods; (2) long-term patency rates would be excellent; (3) limb salvage rates would be correspondingly high; (4) aneurysmal degeneration would not occur, and (5) venous morbidity would be minimal.

METHODS

Since 1990, 41 patients have undergone complete or partial aortoiliac/femoral reconstruction with 63 SFPVs with a mean (+/-SD) follow-up time of 32 +/- 21 months. With the exception of two patients lost to follow-up, all have been observed at 6-month intervals with clinical examination and noninvasive tests.

RESULTS

There were no immediate operative deaths, but three patients (7.3%) died of multisystem organ failure after 1 month. Forty-nine percent of patients had significant perioperative complications including amputation (5%), compartment syndrome (12.3%), and pulmonary embolism (2.4%). Most patients (85%) had multilevel occlusive disease, and the mean SVS/ISCVS runoff score for the group was 4.9 +/- 2.6 (1 = normal, 10 = no runoff). Fifty-eight percent of all distal anastomoses were end-to-end, and in 68% of limbs the profunda femoris artery or superficial femoral artery was the sole runoff vessel. At 5 years, the cumulative secondary patency rate was 100%; primary patency rate, 83%; limb retention rate, 86%; and survival rate, 69%. Four patients had permanent limb edema controlled by compression stockings but none have had venous ulceration. There has been no aneurysmal dilation of SFPV grafts, and mean diameter shown by serial duplex imaging at 6 months (10.8 +/- 1.1 mm) was not significantly different from that at 60 months (7.8 +/- 1.1 mm).

CONCLUSIONS

Aortoiliac/femoral reconstruction with SFPVs is a successful and durable option for infection and other complex aortic problems.

Redo aortic grafting after treatment of aortic graft infection

PURPOSE

This study was performed to determine the indications, operative strategy, and hemodynamic benefit of redo aortic grafting procedures after earlier excision of an infected aortic graft.

METHODS

Among 164 patients treated for aortic graft infection, 15 later underwent redo aortic grafting procedures an average of 18 months (range, 1 to 59 months) after removal of an infected aortic graft. Redo grafting procedures were performed for leg ischemia (n = 11) or infection (proven, n = 3; suspected, n = 1). The new aortic graft originated either from the distal thoracic aorta (n = 5) or from the juxtarenal aortic stump (n = 10). Follow-up averaged 56 months (range, 7 to 110 months).

RESULTS

All patients survived the redo grafting procedure. In the eleven patients who had ischemic symptoms, redo grafting procedures uniformly resulted in symptomatic improvement with an increase in ankle-brachial indexes (0.78 +/- 0.34 vs 0.50 +/- 0.29; p = 0.02). A graft limb occlusion developed in two of these patients (3 and 6 months), but no limbs were amputated. In the four patients who had proven or suspected extraanatomic bypass graft infection, there was one graft limb occlusion (29 months) and one amputation (17 months). Overall, recurrent graft infection occurred in three of 15 patients and may be more frequent in patients who have a proven extraanatomic bypass graft infection (2 of 3 vs 1 of 12; p = 0.08). Infection accounted for two of the three graft limb occlusions and two of the three late deaths. Recurrent infection was not associated with early (< 1 year) regrafting procedures, and culture results did not correlate with the microbiologic features of the primary infection.

CONCLUSIONS

Redo aortic grafting procedures can be performed safely and at relatively early intervals (6 to 12 months) after removal of the infected aortic graft. The procedure reliably relieves ischemic symptoms of the hemodynamically inadequate extraanatomic bypass graft. Reinfection remains a risk after redo aortic grafting procedures, particularly when treating established extraanatomic bypass graft infection.

Candida parapsilosis vertebral osteomyelitis

A case of culture verified Candida parapsilosis lumbar spondylodiscitis, with infectious involvement of an aortic prosthetic graft, presented with a lumbar radicular pain syndrome. Only 33 Candida infections of the spine are described in the literature. Candida parapsilosis was cultured in three cases. Considering the poor general condition of the patient, a conservative treatment with bedrest, casting and amphotericin B, hydrocortisone and itraconazol was given. The patient died 28 months after onset from intercurrent pneumonia.

Secondary aortoenteric fistula: contemporary outcome with use of extraanatomic bypass and infected graft excision

PURPOSE

The standard treatment for secondary aortoenteric fistula (SAEF) has been infected graft removal (IGR) and extraanatomic bypass (EAB), an approach criticized for its high rate of death, amputation, and disruption of aortic closure. Recently, graft excision and in situ graft replacement has been proposed as a safer treatment alternative. Because the current outcome that can be achieved by use of the standard treatment of SAEF has really not been established, we reviewed the records of 33 patients treated for SAEF at our institution during a contemporary time interval (1980 to 1992).

METHODS

Thirteen patients (39.4%) were admitted with evidence of gastrointestinal bleeding and infection, whereas nine (27.3%) only had bleeding, 10 (30.3%) only had signs of infection, and one SAEF was entirely occult (graft thrombosis). Four patients required emergency operation. The fistula type was anastomotic in 13 (39.4%) patients, paraprosthetic in 15 (45.5%), and not specified in 4 cases. Thirty-two patients underwent EAB followed immediately by IGR (n = 16, 48.5%) or followed by IGR after a short interval, averaging 3.9 days (n = 16, 48.5%). The final patient underwent IGR, followed by EAB.

RESULTS

Follow-up on 31 patients (93.9%) averaged 4.4 +/- 3.7 years. There were nine deaths (27.3%) resulting from the SAEF, six perioperative and three late. Three patients (9.1%) had disrupted aortic closure. There were four amputations in three patients (9.1%), two perioperative and two late. Late EAB infection occurred in five patients (15.2%), leading to one death and one amputation. EAB failure occurred in six patients, two during operation and four late, leading to one amputation. The cumulative cure rate for this SAEF group was 70% at 3 years and thereafter. Compared with our earlier SAEF experience, this is a decline of 21% in the mortality rate, 19% in aortic disruption, and 27% in limb loss.

CONCLUSIONS

We conclude that outcome reports based on SAEF series extending over long time intervals do not accurately represent the results that are currently achieved with standard SAEF treatment with use of EAB plus IGR. This improved outcome is attributed to wide debridement of infected tissue beds, reduced intervals of lower body ischemia, and advances in perioperative management. To determine whether any new treatment approach actually offers improved outcome in the management of SAEF, comparison with EAB plus IGR should be limited to patients treated within the last decade at most.

Antibiotic irrigation and conservative surgery for major aortic graft infection

PURPOSE

Traditional surgical treatment for panprosthetic aortic graft infection entails radical excision of the graft, aortic stump closure, and extraanatomic revascularization of the lower limbs. This carries an early mortality rate of 24% to 45%. Amputation rates range from 11% to 37%. Multiple operations and prolonged hospital stay are usual. We have developed a more conservative management technique with the aim of improving outcome.

METHODS

We describe an innovative method of treating the condition with prolonged, high-dose, local antibiotic irrigation therapy, systemic antibiotic treatment, surgical debridement, and graft conservation in a prospectively studied series of 10 patients.

RESULTS

The actual 30-day patient survival rate is 90%, the 1-year survival rate is 80%, and the 4-year survival rate is 67%. Two patients died because of graft infection, and the third died, uninfected, of an unrelated cause. No limbs have been amputated. Only two patients required a second operation. Mean postoperative hospital stay was 32 days. The seven survivors have been closely followed up with regular computed tomography or indium scanning and clinical examination and appear to be free from infection at a mean of 61 months after cessation of irrigation therapy.

CONCLUSION

The technique appears to represent a significant improvement in the management of this major complication of vascular surgery.

Infected abdominal aortic grafts

Aortic grafts were inserted in 1711 patients at Ottawa Civic Hospital (OCH) between 1976 and 1986. Aorto-iliac occlusive disease was the indication in 884 while in 827, the graft was inserted for abdominal aortic aneurysms. Graft infection occurred in 12 patients; six presenting with gastrointestinal bleeding due to aorto-enteric fistula (AEF) and the other six presenting with groin abscesses, mostly as a draining sinus. These were treated with graft excision and immediate extra-anatomic bypass. Seven patients died, giving a mortality rate of 58%. Three surviving patients required above-knee amputatio. These results are comparable to the results of others in the literature; therefore, continuing assessment of all aspects of graft infection and the search for more effective methods of prevention and management are needed.

The management of the infected aortic prosthesis: a current decade of experience

PURPOSE

Newer approaches to the patient with an infected aortic graft are available. We reviewed a recent 10-year experience with a more traditional approach to evaluate its outcome in the 1990s.

METHODS

From January 1983 to January 1993, 27 patients with an aortic graft infection were treated at our institution. There were 18 paraprosthetic infections, eight graft enteric erosions, and one aortoduodenal fistula. The involved bypasses included 20 aortofemoral (74%), five aortoiliac (18%), and two aortic tube grafts (8%). Nineteen aortic replacements were done originally for aneurysmal disease (70%). We reviewed the outcome of each patient treated as it related to the method of management. The therapy for graft infection consisted of aortic graft removal and axillofemoral bypass in 20 patients (74%), treatment by an in situ method in four patients (15%), excision of an aortofemoral limb and extraanatomic bypass in two patients (7%), and extraanatomic bypass alone in one patient (4%). In the group treated by graft removal and extraanatomic bypass, four patients (20%) had staged operations (extraanatomic bypass followed by interval aortic graft removal), nine (45%) had single operations with extraanatomic bypass preceding graft removal, and seven (35%) had single operations with graft removal preceding extraanatomic bypass.

RESULTS

The 30-day operative mortality rate was 3.7%. There were no instances of aortic stump blowout. The 3-year primary patency rate for axillofemoral bypass limbs was 80.2%, and the secondary patency rate was 87.4%. No limbs were lost as a result of ischemic complications. There was one late amputation for an unrelated problem.

CONCLUSIONS

The results of alternate approaches to the management of patients with infected aortic grafts were equivalent both in terms of perioperative mortality and morbidity rates in this group of patients. Complete excision of the aortic graft with axillofemoral bypass provided a satisfactory long-term outcome and remains the standard with which other approaches must be compared.

Creation of a neo-aortoiliac system from lower extremity deep and superficial veins

OBJECTIVE

This study evaluated the morbidity, mortality, and intermediate term follow-up of patients undergoing replacement of their aortoiliac-femoral systems with lower extremity deep and superficial veins.

SUMMARY BACKGROUND DATA

The most commonly used treatment for aortic prosthetic infection is ectopic bypass and removal of the prosthesis. The overall mortality rate with this approach is approximately 20%, with an amputation rate of 10% to 14%. Other limitations include thrombosis of the ectopic bypass leading to limb loss, reinfection of the ectopic bypass, and aortic stump blowout. Dissatisfaction with this approach has led the authors to develop the following.

METHODS

A neo-aortoiliac system (NAIS) was fashioned from lower extremity deep veins (DV), greater saphenous veins (GSV), or both in patients with infected aortobifemoral prosthesis (n = 17) and other complex aortic problems (n = 3). Removal of infected prosthetic material, harvest of vein, and creation of NAIS was performed as a single-staged procedure.

RESULTS

The in-hospital mortality and amputation rates were 10% each. The mean (+/- standard deviation [SD]) operative time was 6.5 +/- 1.8 hours and the blood transfusion requirement was 4 +/- 3 units. Four patients experienced postoperative gastrointestinal complications with peritonitis and sepsis; NAIS vein graft resisted infection and remained intact. The mean follow-up time was 22.5 +/- 16 months. NAISs constructed from GSVs were prone to the development of focal stenoses requiring intervention or diffuse neointimal hyperplasia leading to occlusion. In contrast, all NAISs from larger caliber DVs have remained widely patent. The failure rate of GSV NAISs was 64%, compared to 0% for DV NAISs (p = 0.006). Despite the high failure rate in patients with GSV NAISs, none has required amputation. In patients who had DVs harvested for NAIS reconstruction, limb edema and other signs of venous hypertension have been minimal.

CONCLUSION

NAIS reconstruction from lower extremity veins is a successful option in patients with extensive aortic prosthetic infection and other complex aortic problems.

Management of primary aortic graft infection by extra-anatomic bypass reconstruction

In this retrospective study, 21 patients requiring treatment for primary infection of an aortic prosthesis between 1981 and 1991 were identified from a prospective register. Ten of the 21 patients had had additional peripheral reconstructive vascular surgery before the diagnosis of aortic graft infection. The median interval between aortic graft insertion and diagnosis of graft infection was 16 months (range 1-84). Infected grafts were removed and an extra-anatomic bypass constructed in all patients. All but three patients had axillodistal reconstruction. Six patients had simultaneous operations, whilst the other 15 patients had a staged procedure with extra-anatomic reconstruction preceding graft removal. Two patients died before discharge from the hospital (9.5%). No patient required extremity amputation in the perioperative period. By life-table analysis patient survival (including perioperative deaths) was 80% at 1 year, 55% at 3 years and 40% at 5 years. Primary patency was 62% at 1 year, 51% at 3 years and 40% at 5 years. Limb salvage rate was 89% at 1 year, 63% at 3 years and 63% at 5 years. The median length of follow-up was 24 months. Extra-anatomic reconstruction in patients with aortic graft infection can be performed with low perioperative mortality. Limb salvage rates following extra-anatomic reconstruction are determined not only by the mode of reconstruction, but also by the primary disease.