Michel Batt

In situ revascularization with silver-coated polyester grafts to treat aortic infection: early and midterm results

PURPOSE In this prospective study we analyzed the immediate and midterm outcome in patients with abdominal aorta infection (mycotic aneurysm, prosthetic graft infection) managed by excision of the aneurysm or the infected vascular prosthesis and in situ replacement with a silver-coated polyester prosthesis. METHODS From January 2000 to December 2001, 27 consecutive patients (25 men, 2 women; mean age, 69 years) with an abdominal aortic infection were entered in the study at seven participating centers. Infection was managed with either total (n = 18) or partial (n = 6) excision of the infected aorta and in situ reconstruction with an InterGard Silver (IGS) collagen and silver acetate-coated polyester graft. Assessment of outcome was based on survival, limb salvage, persistent or recurrent infection, and prosthetic graft patency. RESULTS Twenty-four patients had prosthetic graft infections, graft-duodenal fistula in 12 and graft-colonic fistula in 1; and the remaining 3 patients had primary aortic infections. Most organisms cultured were of low virulence. The IGS prosthesis was placed emergently in 11 patients (41%). Mean follow-up was 16.5 months (range, 3-30 months). Perioperative mortality was 15%; all four patients who died had a prosthetic graft infection. Actuarial survival at 24 months was 85%. No major amputations were noted in this series. Recurrent infection developed in only one patient (3.7%). Postoperative antibiotic therapy did not exceed 3 months, except in one patient. No incidence of prosthetic graft thrombosis was noted during follow-up. CONCLUSION Preliminary results in this small series demonstrate favorable outcome with IGS grafts used to treat infection in abdominal aortic grafts and aneurysms caused by organisms with low virulence. Larger series and longer follow-up will be required to compare the role of IGS grafts with other treatment options in infected fields.

An Analysis of the French Multicentre Experience of Fenestrated Aortic Endografts: Medium-Term Outcomes

Purpose:To evaluate the medium-term outcomes following aortic aneurysm repair utilizing fenestrated endografts performed in 13 French academic centers. Materials and Methods:A retrospective analysis of prospectively collected data. All patients had asymptomatic aneurysms involving or close to the visceral-bearing abdominal aorta and were judged to be at high-risk for open surgical repair. Fenestrated endografts were designed using computed tomography reconstructions performed on three-dimensional workstations. The procedures were conducted under fluoroscopic control by experienced endovascular teams. All patients were evaluated with computed tomography, duplex ultrasound, and plain film radiograph at discharge, 6, 12, 18, and 24 months, and annually thereafter. Results:Eighty patients (78 males) were treated over 44 months (May 2004–January 2008). Median age and aneurysm size were 78 years (range: 48–90 years) and 59 mm (range: 47–82 mm), respectively. A total of 237 visceral vessels were perfused through a fabric fenestration (median of 3 per patient). One early conversion to open surgery was required. Completion angiography showed that 234 of 237 (99%) target vessels were patent. Two patients (2.5%) died within 30 days of device implantation. Predischarge imaging identified 9 (11%) endoleaks: 3 type I, 5 type II, and 1 type III. The median duration of follow-up was 10 months (range: 1–38 months). No aneurysms ruptured or required open conversion during the follow-up period. Four of 78 (5%) died during follow-up (actuarial survival at 24 months 92%), none of these deaths were aneurysm related. Aneurysm sac size decreased by more than 5 mm in 33%, 53%, and 58% at 6, 12, and 18 months, respectively. One patient had sac enlargement within the first year, associated with a persistent type II endoleak. In-stent stenoses or occlusion affected 4 renal arteries. Secondary procedures were performed in 8 patients (10%) during follow-up, 5 to correct endoleaks and 3 to correct threatened visceral vessels. Conclusions:The use of endovascular prostheses with graft material incorporating the visceral arteries is safe in high risk patients with high risk aneurysms. In the medium-term it is effective in preventing rupture. However, meticulous follow-up to assess sac behavior and visceral ostia is critical to ensure optimal results.

Expanded polytetrafluoroethylene arterial prostheses in humans: histopathological study of 298 surgically excised grafts

The expanded polytetrafluoroethylene vascular prosthesis is considered to be the best synthetic alternative for peripheral arterial reconstruction. Most studies on the healing characteristics of expanded polytetrafluoroethylene prostheses have been carried out on animals, and very few data are available on prosthesis implanted in humans long term. We implanted 298 expanded polytetrafluoroethylene grafts as arterial substitutes in humans. The mean duration of implantation was 523 d and the grafts were implanted mainly for infrainguinal or axillofemoral bypass. The cellular and collagen infiltration of the microporous expanded polytetrafluoroethylene structure was generally poor. Infiltration occurred mainly in the external region of the prosthetic wall and increased with the duration of implantation. The external reinforcement was not a major factor in limiting tissue infiltration. The luminal surfaces were covered with a thin, irregular layer of organized fibrin, interspersed with exposed expanded polytetrafluoroethylene areas. Mineral deposits were observed in five cases. Despite poor healing, the clinical performance of expanded polytetrafluoroethylene vascular prostheses is relatively good. Since the chief advantage of this material is good mechanical stability in vivo, any modifications of the graft to improve healing characteristics or thrombogenic properties should not be made at the expense of stability in vivo.

Carotid Endarterectomy Plaques: Correlations of Clinical and Anatomic Findings

To establish possible relationships between the structure of carotid plaque and neurologic symptoms, 187 consecutive endarterectomy specimens were studied prospectively. Each specimen was examined for gross and histopathological features. Intraplaque hemorrhage, although found infrequently, was closely correlated with the presence of symptoms. Plaque ulcerations were encountered more often when lesions were symptomatic. Calcifications were more frequently associated with asymptomatic lesions. Consistency of plaque was related to its morphological features (stenosis or ulceration) and symptoms. Soft plaques with predominant atheromatous grumous material and hemorrhage were associated more often with tightiy stenotic, ulcerated, and symptomatic lesions. Consistency of atherosclerotic carotid plaques should be assessed and considered as an important element in the therapeutic decision.

Percutaneous closure devices for endovascular repair of infrarenal abdominal aortic aneurysms: a prospective, non-randomized comparative study.

PURPOSE This study was designed to describe and evaluate our preliminary results with a percutaneous arterial closure device as compared to those obtained with conventional femoral surgical cut down during endovascular repair of abdominal aortic aneurysms (AAA). MATERIAL AND METHODS Between January 2004 and December 2006, 40 of 86 AAA patients selected for endovascular repair met the criteria for inclusion in this study. Nineteen of these patients (Group A) received a bifurcated endograft placed by direct puncture of the femoral arteries (38 femoral triangles) with closure by a Prostar((R)) percutaneous arterial closure device (Abbott). The other 21 patients (control group B) were managed with a bifurcated endograft placed by conventional open surgery (42 femoral triangles). Data concerning all 40 patients were collected prospectively and analyzed. RESULTS The technical success rate was 92% (group A) vs 90% (group B), P=0.79. The incidence of perioperative complications was 16% (3/19) in group A and 14% (3/21) in group B (P=0.89). The mean hospital stay was 5.8 days in group A and 7.8 days in group B (P=0.05). The difference in the length of hospitalisation was associated with reduced cost for the percutaneous group (5579.60 euros vs. 7503.60 euros; P=0.04), that counterbalanced the cost induced by the Prostar XL((R)) suture mediated device. Mean follow-up in both groups was 12 months. The overall incidence of locoregional complications after one year of follow-up was 11% (2/19) in group A and 19% (4/21) in group B (P=0.45). CONCLUSION This study confirms the feasibility and safety of total percutaneous endovascular AAA repair. Our preliminary results suggest that the costs paid by healthcare providers for endovascular AAA repair might not be increased with the selective use of percutaneous closure devices.

In-situ Revascularisation for Patients with Aortic Graft Infection: A Single Centre Experience with Silver Coated Polyester Grafts

OBJECTIVE The aim of this study was to evaluate the early and mid term outcome of patients with aortic graft infection who underwent in-situ revascularisation with a silver coated prosthesis. MATERIAL From January 2000 to December 2006, 24 consecutive patients (22 male, 2 female) with mean age 67 years were prospectively entered in this study of aortic graft infection at our single centre. Infection was managed with either total (n=19) or partial (n=5) excision of the infected graft and in- situ reconstruction with a silver coated prosthesis, Inter Gard Silver (IGSG). METHODS The primary endpoint was recurrence of infection. Secondary endpoints were early and late mortality, peri-operative morbidity, primary graft patency, major amputation rates and patient survival. RESULTS Fourteen patients had a primary graft infection, however 10 of 24 patients had graft infection secondary to aorto digestive (n=9) or aorto urinary (n=1) tract fistulas. Bacteriological cultures were negative in 8 (33%) patients. Most organisms cultivated where virulent and the majority of graft infections were polymicrobial (71%). Silver grafts were placed emergently in 6 (25%) patients. Mean follow up 32.5+/-31.0 months (range 2-78 months). Peri-operative morbidity and mortality were 46% and 21% respectively. Early interventions occurred in 6 (25%) patients and late secondary intervention were required in 3 (15.7%), caused by silver graft reinfection. The late mortality was 26%. CONCLUSION In-situ reconstruction with the silver graft confirms similarity with other modalities. The greatest advantage for the silver graft is its ease of use but the risk of reinfection remains significant.

Early and Late Results of Contemporary Management of 37 Secondary Aortoenteric Fistulae

PURPOSE Evaluate the results of the two modalities used for the treatment of Secondary Aorto-Enteric Fistula (SAEF): In situ Reconstruction (ISR) and Extra-Anatomic Reconstruction (EAR). The primary endpoints of this study were early standard 30-day mortality and reinfection (RI). Secondary endpoints were perioperative morbidity, late mortality, primary graft patency, and major amputation rates. MATERIAL & METHOD Diagnosis of SAEF was based on clinical examination and the results of pre-operative duplex or CT scans. Surgical management was performed according to local protocols at the participating institutions: - Elective surgery: ISR or staged EAR. - Emergency surgery: aortic clamping followed by ISR or EAR. - Selected high-risk patients: endovascular repair. Statistical analyses were performed using the actuarial method. Univariate analysis was used for analysis of categorical variables, and multivariate analysis was performed with a Cox proportional hazard regression. RESULTS A total of 37 patients were included in this retrospective multicentre study. Mean follow-up was 41 months. The majority of the patients (20, 54%) presented acutely. EAR was performed in 9 patients (24%), ISR in 25 (68%), and 3 patients underwent endovascular repair. Bacteriological cultures were negative in 3 patients (9%). The most frequent organisms identified were Candida species and Escherichia coli. The 30-day mortality was 43% (16 patients). Patient age (>75 years) was the sole predictive factor associated with operative mortality (p = 0.02); pre-operative shock was not statistically significant (p = 0.08). There were 2 graft thromboses and 1 femoral amputation. Primary graft patency was respectively 89% at 1 year and 86% at 5 years; limb salvage rates were 100% at 1 and 5 years and 86% at 6 years, with no difference between ISR and EAR. RI occurred after 9.3 ± 13 months in 8 of 17 surviving patients and was fatal in all cases. For all surviving patients, the RI rate at 1 and 2 years was 24% and 41% respectively. There was no significant difference in the rate of RI after ISR or EAR. CONCLUSION EAR does not appear to be superior to ISR. The risk of RI increased with the length of follow-up, irrespective of the treatment modality. Life-long surveillance is mandatory. Our results with endovascular sealing of SAEF should be considered a bridge to open repair.

A Comparison of the Mid-term Results Following the use of Bifurcated and Aorto-uni-iliac Devices in the Treatment of Abdominal Aortic Aneurysms

PURPOSE To compare the mid-term results following the use of bifurcated (ABIS) and aorto-uniiliac (AUIS) endovascular devices in the treatment of abdominal aortic aneurysms (AAA) in a population of patients deemed to be at high risk for open surgery. MATERIAL AND METHODS Over a 4 year period (January 2003 to December 2007), 447 underwent elective endovascular aneurysm repair (EVAR) using ZENITH) stent-grafts. Group I comprised patients treated using the AUIS (n=124), and group II those receiving ABIS (n=323). Outcome measures included the assisted technical success rate, perioperative mortality, major complications, freedom from reintervention, and primary and secondary patencies. Factors associated with mid-term clinical failures were determined using univariate and multivariate analyses. RESULTS The assisted primary technical success rate was 94% and 99% in groups I and II respectively (p=.002). Major perioperative complications occurred in 13 group I patients (10%) vs. 12 group II patients (4%) (p=.005). The 30-day mortality rate was 3.2% vs.1.5% (p=0.2). TASC C and D iliac lesions significantly increased the risk of major perioperative complications (35% vs. 3%; OR=14.94; 95% CI: 5.75 to 38.78; p<.0001). During the follow-up period (median 24 months), secondary procedures were required in 11% and 5% of group I and group II patients respectively (p=.01). Freedom from reintervention at 12, 24 and 36 months was 98%, 90%, and 85% in group I vs. 96%, 92%, and 92% in group II (P<0.005). The primary and secondary patency rates at 3 years were 92% vs. 98% (p=.003) and 97% vs. 99% (p=.04) for groups I and II respectively. In group I, the Crossover Femoro-Femoral Bypass (CFFB) was responsible for 3 major complications (2.4%) which occurred at 7, 12 and 57 months of follow-up. However, the use of AUIS with CFFB did not independently increase the risk of major complications during follow-up (HR=0.108; 95% CI: 0.007 to 1.637; p=.11, Cox proportion model). In both univariate and multivariate analysis, concomitant iliac arterial occlusive disease (IAOD) was the only significant predictor of clinical failure in study population as a whole (OR=3.996; 95% CI: 1.996 to 7.921; p<.0001). CONCLUSION This study demonstrates that ABIS is associated with better results than AUIS in the management of patients with AAA. Iliac artery occlusive disease was more frequently diagnosed in the AUIS group and this was significantly associated with a higher risk of complications, while the crossover graft itself was not. Nevertheless, the outcomes for both groups are encouraging in this high risk population.

Expanded PTFE Prostheses as Arterial Substitutes in Humans: Late Pathological Findings in 73 Excised Grafts

Through collaboration of surgeons, pathologists and bioengineers at five centers in Canada and France, this study analyzed the late pathology and structural changes in 73 expanded PTFE arterial prostheses harvested from patients at autopsies and reoperations. The degree of tissue encapsulation increased with the duration of implantation but was reduced by the presence of infection. In several cases, the fibrous tissue penetrated the wall of the prosthesis and partitioned off the thin outer layer, thus disrupting the delicate microporous structure of the wall. The presence of aneurysms was observed in models that had no external reinforcing layer and among grafts that apparently suffered from surgical trauma. Wrinkling of grafts was noted at areas of flexion and was often associated with thickening of the external capsule and reduced luminal diameters. Endothelialization was found within only a few millimeters of the anastomoses. The luminal surfaces were generally not well healed. The PTFE structure was usually readily visible under a thin covering of loosely adhering thrombotic deposits. Bacteria were observed in 46% of the cases, even though only 29% were considered clinically infected. The incidence of lipid or cholesterol deposits was high. Avoiding iatrogenic trauma to the external wall of the prosthesis during implantation is important. Those features where design improvements are required to provide longer term structural integrity and dimensional stability in future models of expanded PTFE prostheses should be identified.

Revascularization of Internal Iliac Arteries during Aortoiliac Surgery: A Multicenter Study

p < 0.001). Associated revascularization of the inferior mesenteric artery was performed in 9% of patients (11.5% with aneurysms vs. 5.5% with occlusive lesions, p < 0.001). Postoperative colonic ischemia was observed in 21 patients (1.2%) (1.2% with aneurysms vs. 1.2% with occlusive lesions) and claudication in the gluteal region was observed in 31 patients (1.7%) (1.5% with aneurysms vs. 2.1% with occlusive lesions). Revascularization of the internal iliac artery, regardless of the technique, had no significant effect on the incidence of postoperative colonic ischemia and claudication in the gluteal region—neither after surgery for aneurysm (0.6% vs. 2.1% and 1.2% vs. 1.9%, respectively) nor after surgery for occlusive lesions (0.9% vs. 0.4% and 1.5% vs. 2.6%, respectively). Whether performed routinely or not, revascularization of the mesenteric artery has no significant effect on the incidence of postoperative colonic ischemia (1.1% vs. 1.3%).