Successful treatment of endotension and aneurysm sac enlargement with endovascular stent graft reinforcement

Abdominal aortic aneurysm (AAA) enlarges after successful endovascular repair because of endoleak, which is persistent blood flow within the aneurysm sac. In the absence of detectable endoleak, AAA may still expand, in part because of endotension, which is persistent pressurization within the excluded aneurysm. We report three patients who underwent successful endovascular AAA repair using the Excluder device (W. L. Gore & Associates, Flagstaff, Ariz). Although their postoperative surveillance showed an initial aneurysm regression, delayed aneurysm enlargement developed in all three, apparently due to endotension. Endovascular treatment was performed in which endograft reinforcement with a combination of aortic cuff and iliac endograft extenders were inserted in the previously implanted stent grafts. The endograft reinforcement procedure successfully resulted in aneurysm sac regression in all three patients. Our study underscores the significance of increased graft permeability as a mechanism of endotension and delayed aneurysm enlargement after successful endovascular AAA repair. In addition, our cases illustrate the feasibility and efficacy of an endovascular treatment strategy when endotension and aneurysm sac enlargement develops after endovascular AAA repair.     

Secondary conversion of the Gore Excluder to operative abdominal aortic aneurysm repair

OBJECTIVE: Reports continue to document the occurrence of major adverse events after endovascular aortic aneurysm repair. Although many of these problems can be successfully managed through endovascular salvage, operative conversion with explantation of the endoprosthesis remains necessary in some patients. We report herein a review of all patients initially enrolled in multicenter US clinical trials of the Excluder endograft who underwent secondary conversion to open surgical repair. METHODS: Clinical data and relevant medical records of patients enrolled in phase I and II multicenter US clinical trials of the Excluder endograft were retrospectively reviewed for adverse events and further narrowed to those patients who underwent secondary operative conversion. Hospital records, operative and anesthesia reports, and all imaging studies were analyzed at initial implantation and at the time of subsequent open surgical repair. RESULTS: Late open conversion was performed in 16 (2.7%) of the 594 patients enrolled in the Excluder clinical trials. Presumed endotension accounted for 8 of 16 of secondary conversions. In two of these patients, however, an endoleak was identified at the time of open surgical repair. Of the remaining eight patients, two underwent conversion for device infection, five for persistent endoleak, and one for aneurysm rupture. The overall 30-day mortality was 6.25% (1/16), with one death occurring in a patient with a ruptured aneurysm. Of patients who underwent conversion because of endotension, the maximal abdominal aortic aneurysm diameter (mean +/- SD) at the time of initial implantation and subsequent graft removal was 61 +/- 11 mm and 70 +/- 10 mm, respectively. The mean time to open conversion for treatment of endotension was 37 +/- 12 months (range, 20-50 months; median, 42 months). Freedom from conversion was 98.6% and 96.7% at 24 and 48 months, respectively. CONCLUSIONS: Endotension in the absence of a demonstrable endoleak has been a major indication for late surgical conversion in patients treated with the Excluder endograft. Given the potential presence of an undetected endoleak and the possible effects of progressive sac enlargement on long-term device stability, continued close surveillance of patients with assumed endotension is required. Should changes in device design eliminate endotension, a further reduction in the already low incidence of late open conversion of the Excluder endograft can be anticipated.     

The effect of endograft relining on sac expansion after endovascular aneurysm repair with the original-permeability Gore Excluder abdominal aortic aneurysm endoprosthesis

OBJECTIVE: Endovascular abdominal aortic aneurysm repair (EVAR) with the original-permeability Excluder (W.L. Gore & Associates, Flagstaff, Ariz) has been associated with postoperative sac expansion in the absence of endoleak. In these cases, we have performed an endovascular revision, relining the original endograft with another Excluder, in an effort to arrest sac expansion by reducing permeability. We have studied these cases to determine the effect of relining on aneurysm expansion. METHODS: Patients who demonstrated sac expansion (>or=5 mm diameter, >or=5% three-dimensional volume) after EVAR with the original Excluder were evaluated. Between 1999 and 2004, the original-permeability endoprosthesis was used in 97 patients who underwent EVAR for asymptomatic abdominal aortic aneurysm (AAA). Sac expansion occurred in 24 patients, of which multiple imaging modalities showed 12 had expansion without demonstrable endoleak. Nine of the 12 have had endovascular relining, and five of these nine have >6 months follow-up to form the primary basis for this report. RESULTS: AAA size was stable or smaller in the first 6 months after the original EVAR for all patients. Once expansion began (typically in the time frame of 6 to 12 months), multimodality imaging showed no aneurysm spontaneously decreased in size without intervention, despite the absence of endoleak (n = 12). Expansion exceeded clinically significant thresholds at 30 months (mean) by diameter criteria and 22 months (mean) by three-dimensional volume criteria for the five patients with >6 months follow-up after relining. Endovascular relining was performed at a mean of 36 months, with a mean hospital stay of 1 day, and no morbidity or mortality. Over the entire duration of expansion (mean, 26 months), aneurysms expanded by 6.0 +/- 1 mm/year diameter and by 12% +/- 2%/year by three-dimensional volume. At a mean of 16 months follow-up after relining with another Excluder, the mean diameter decrease was 2.0 mm/year (P < .03) and the mean volume decrease was 2.6%/year (P < .01). After relining, all AAAs were smaller by diameter or volume, or both, exceeding thresholds defining shrinkage in two of the five with >6 months follow-up after relining. There was no rupture, migration, endoleak, conversion to open repair, or aneurysm-related death in any patient. CONCLUSIONS: It appears from the initial follow-up that AAA expansion owing to permeability issues after EVAR with the original Excluder can be arrested by endovascular relining with a low-permeability Excluder endoprosthesis.     

Late abdominal aortic aneurysm enlargement after endovascular repair with the Excluder device

OBJECTIVES: Behavior of the abdominal aortic aneurysm (AAA) sac after endovascular abdominal aortic aneurysm repair (EVAR) is graft-dependent. The Excluder endograft has been associated with less sac regression than some other stent grafts. Long-term follow-up has not been reported. METHODS: Between May 1999 and July 2002, 50 patients underwent EVAR with the Excluder bifurcated endoprosthesis. These patients were followed up prospectively with computed tomography (CT) at 1, 6, and 12 months and yearly thereafter. One immediate conversion to open surgery and three deaths occurred within 6 months. One additional patient was lost to follow-up. The remaining 45 patients, 35 men and 10 women, were followed up for at least 1 year, and form the basis for this report. Their mean age was 73 +/- 5.5 years. The minor axis diameter at the largest area of the AAA on CT examination was compared with the baseline measurement at 1 month and to the smallest size previously recorded during follow-up. Change in sac size of 5 mm or greater was considered significant. Mean follow-up was 2.7 +/- 1.2 years (range, 1-4 years). Nominal variables were compared with the chi(2) test, and continuous variables with the Student t test. RESULTS: A significant decrease in average AAA sac diameter was observed at 6-month, 1-year, and 2-year follow-up. These differences were lost by the 3-year evaluation, because of delayed sac growth (n = 9) and re-expansion of once shrunken aneurysms (n = 3). The probability of freedom from sac growth or re-expansion at 4 years was only 43%. At last follow-up, sac expansion occurred in the absence of active endoleak in nine patients. Type II endoleak was associated with sac expansion in three patients (P =.003), resulting in one conversion to open surgery after the 4-year follow-up. No graft migrations, AAA ruptures, or aneurysm-related deaths were noted. CONCLUSIONS: Late aneurysm sac growth or re-expansion after EVAR with the Excluder device is common, even in the absence of endoleak. Although the incidence of important clinical sequelae is low at this point, the incidence of aneurysm expansion should be taken into consideration during the risk-benefit assessment before EVAR repair with the Excluder device.     

Variable sac behavior after endovascular repair of abdominal aortic aneurysm: analysis of core laboratory data

OBJECTIVES: The behavior of the aneurysm sac after endovascular grafting has been the subject of significant speculation. The importance of sac behavior is manifested by the correlation between aneurysm size or size change and risk for rupture, and potentially further extrapolated to define the need for secondary intervention. This study was undertaken to define graft-specific differences and the effect of endoleak on sac remodeling. METHODS: Core laboratory data were obtained for three US Phase II clinical trials. Patients were included if they met anatomic inclusion criteria and underwent placement of the latest version of a bifurcated endovascular prosthesis. Unsupported Dacron (Ancure), supported Dacron (Zenith), and expanded polytetrafluoroethylene (Excluder) grafts were evaluated. Digitized images were electronically assessed for aneurysm size (area, maximum, minimum diameter) with National Institutes of Health Image software. Two blinded reviewers analyzed each radiographic study to ensure accurate image selection and establish the presence or absence of endoleak. A third reviewer adjudicated discrepancies. chi(2) analysis and mixed nonlinear modeling were used to analyze the results. RESULTS: Of 1506 patients evaluated, 723 (227 Ancure, 343 Excluder, 153 Zenith) met inclusion criteria for the study. Mean follow-up was 23.2 months (Ancure, 31.3 months; Excluder, 19.6 months; Zenith, 19.3 months). The incidence of any endoleak was 39.1% (Ancure, 58.1%; Excluder, 34.7%; Zenith, 20.9%; P <.001). Type of prosthesis, presence or absence of endoleak, and baseline size were determinants of rate of aneurysm shrinkage. Reduction in sac size was greatest with the Zenith graft, followed by the Ancure and Excluder grafts. Presence of endoleak had a moderating effect on rate of sac shrinkage with the Zenith and Ancure grafts; however, sac size increased in the presence of endoleak with the Excluder graft. Finally, baseline size was positively correlated with rate of aneurysm shrinkage. CONCLUSIONS: The behavior of the aneurysm sac depends on the type of prosthesis, presence or absence of endoleak, and baseline size of the sac. Differential sac behavior must be considered when determining the need for secondary interventions, timing follow-up studies, and assessing success or failure of endovascular repair.     

The Gore Excluder US multi-center trial: analysis of adverse events at 2 years

Although open surgical repair of abdominal aortic aneurysms remains the standard of care, endovascular repair is becoming an attractive alternative as more long-term outcome data become available to show its safety and efficacy. The authors review data on the 2-year outcome of the pivotal US multicenter, prospective Gore Excluder Trial. Patients treated with the Excluder endograft (W.L. Gore, Flaggstaff, AZ) had less blood loss (310 +/- 19 v 1,590 +/- 124 mL; P <.0001), required fewer homologous transfusions (6% v 32%; P <.0001), and had faster inpatient recovery (2.0 +/- 0.1 v 9.8 +/- 1.4 days; P <.0001) compared with those treated with open repair. Early major adverse events were reduced significantly in the patients treated with the endograft (14% v 57% in control; P <.0001), and this persisted at 2 years. There was no difference in overall survival rate (P =.13). There were no deployment failures, early conversions, or aneurysm ruptures. At the 2-year time-point, trunk migration occurred in 1%, limb migration in 1%, limb narrowing in 1%, endoleak in 20%, and aneurysm growth in 14%. There was a 7% annual reintervention rate in the endograft group in the first 2 years. The Excluder endograft is a safe and effective treatment compared with open surgical repair for infrarenal abdominal aortic aneurysms with appropriate anatomy.     

Aortoesophageal fistula after thoracic endovascular aortic repair and transthoracic embolization

Endografts are more commonly being used to treat thoracic aortic aneurysms and other vascular lesions. Endoleaks are a potential complication of this treatment modality and can be associated with aneurysmal sac expansion and rupture. This case report presents a patient who developed a type IA endoleak after endograft repair of a descending thoracic aneurysm. The endoleak was successfully treated through computed tomographic-guided transthoracic embolization, although the patient experienced lower extremity paraparesis postprocedurally. The patient's endovascular repair was complicated by the development of an aortoesophageal fistula and endograft infection necessitating operative débridement and endograft explantation.     

Device-specific aneurysm sac morphology after endovascular aneurysm repair: evaluation of contemporary graft materials

OBJECTIVE: This study analyzed device-specific aneurysm sac morphology after endovascular aneurysm repair (EVAR) with low-permeability devices. METHODS: Between September 2004 and May 2006, 122 patients were treated with EVAR. Three different devices were implanted: 47 Zenith (Cook, Indianapolis, Ind), 46 AneuRx (Medtronic, Santa Rosa, Calif) with Resilient Dacron Graft Material, and 29 Excluder (W. L. Gore & Associates, Flagstaff, Ariz) with low-porosity polytetrafluoroethylene (PTFE). Patients were followed up at 1, 6, and 12 months and then biannually with computed tomography (CT) angiography. Standard axial two-dimensional CT measurements were obtained and compared with preoperative imaging. The preoperative scan served as a baseline, and the minor axis diameter, measured at the largest axial cut of the abdominal aortic aneurysm, was compared with the same measurement at follow-up. RESULTS: Patient age, sex, and preoperative aneurysm morphology were similar among groups. Patients receiving the Zenith endograft had a significantly larger neck diameter; however, there was no difference in the neck length between groups. The rate of type II endoleaks was similar for the Zenith (17%), AneuRx (17%), and Excluder (14%). At 1, 6, 12, and 18 months, all three grafts were associated with sac shrinkage. The resulting decreases in mean aneurysm size at 18 months and corresponding shrinkage were Zenith, 11%, 6.4 +/- 1.8 mm; AneuRx, 18.9%, 12.7 +/- 2.7 mm; and the Excluder, 5.5%, 3.3 +/- 0.9 (P < .05). The sac size in the 19 patients with a type II endoleak decreased 8.06% compared with a 15.43% decrease in sac size in patients without endoleak at 6 months. No significant sac expansion > or =5 mm has been observed among any of the groups to date. CONCLUSIONS: Sac regression with all devices appears to have been favorably influenced by the new generation of graft materials and is improved compared with published reports of older generation graft materials for the AneuRx and Excluder. However, there is a trend toward greater sac regression with devices using Dacron vs PTFE. The relationship of aneurysm morphology and long-term effects on aortic stent grafts is yet to be determined.     

Total robotic ligation of inferior mesenteric artery for type II endoleak after endovascular aneurysm repair

We present a case of totally robotic ligation of the inferior mesenteric artery (IMA) for treatment of a persistent endoleak from the IMA into the aneurysm sac after endovascular aneurysm repair (EVAR). An 84-year-old male underwent EVAR with a Gore Excluder stent graft for an asymptomatic infrarenal abdominal aortic aneurysm. Follow-up computed tomographic (CT) scan showed persistent type II endoleak from the IMA, with progressive enlargement of the aneurysm sac from 5 to 6.1 cm over an 18-month period. In this case, the patient underwent ligation of the IMA using the da Vinci Surgical System for the treatment of retrograde flow into the aneurysm sac. The total operating time was 249 min; of this, the robotic assistance time was approximately 180 min. No intraoperative complications occurred. The estimated blood loss was 50 mL and the urine output 650 mL. The patient was extubated immediately after the procedure and tolerated a regular diet the following day. He was discharged home with a urinary catheter on postoperative day 2. CT scan postoperatively and at 3-month follow-up demonstrated an occluded IMA and stabilization of the aneurysm sac size.     

Sac behavior after aneurysm treatment with the Gore Excluder low-permeability aortic endoprosthesis: 12-month comparison to the original Excluder device

BACKGROUND: The original Gore Excluder endoprosthesis (OGE) used both during and briefly after clinical trials was associated with less sac regression and more sac growth than some other devices, even without apparent endoleaks, presumably because of transmural movement of serous fluid across the expanded polytetrafluoroethylene material. In July 2004, the device was modified to decrease graft permeability. This study evaluated the efficacy of the new Excluder Low-Permeability Device (ELPD) at 1 year and compared it with the OGE and the Cook Zenith device (ZEN). METHODS: From Food and Drug Administration approval of the Excluder in November 2002 until June 2005, 283 patients underwent endovascular repair of abdominal aortic aneurysms with the Gore Excluder or the ZEN. Postoperative surveillance included computed tomographic scans at 1 and 12 months; 181 (64%) patients completed both scans. The 1-month computed tomographic scan served as a baseline, and the minor axis diameter, measured at the largest axial cut of the abdominal aortic aneurysm, was compared with the same measurement at 1 year. A sac size change of 5 mm or more was considered significant. Sixty patients treated with the OGE were compared with 72 patients treated with the ELPD. Forty-nine patients treated during the same time period with the ZEN, known for early sac shrinkage, were used as a reference. All measurements were performed by one observer from a digital workstation. Wilcoxon signed rank tests (pairwise) or Kruskal-Wallis tests (three groups) were used for intergroup comparison of continuous variables, whereas chi2 statistics or Fisher exact tests were used to compare categorical variables. RESULTS: Patient age and sex and mean maximum aneurysm diameter at baseline were similar among groups (P = .59, .27, and .46, respectively). Graft migration, stent fractures, acute surgical conversion, late abdominal aortic aneurysm rupture, or aneurysm-related deaths were not observed. Type II endoleak rates were similar between ELPD and ZEN (23.6% and 20.4%; P = .68). Although a higher rate of endoleaks was seen with OGE (36.7%), this was not significant when compared with the other two devices (P = .11). At 1 year, patients treated with ELPD had a sac regression rate that was significantly higher than that for patients treated with OGE (63.9% vs 25%; P < 0.001) and was similar to that for patients treated with ZEN (65.3%). Significant sac expansion was not observed with ELPD. CONCLUSIONS: At 1 year, similar to ZEN, significant aneurysm sac regression and minimal sac expansion were noted after endovascular repair of abdominal aortic aneurysms with ELPD. Low-porosity fabric used in the construction of endoprostheses seems to be an important factor in early aneurysm sac shrinkage. Long-term efficacy regarding the prevention of sac enlargement remains unclear, and further follow-up is suggested.     

First report of a late type III endoleak from fabric tears of a Zenith stent graft

We report a case of a late type III endoleak from a hole in the fabric of the main body of a Zenith bifurcated endograft 7 years after implantation. Abdominal pain and a rapidly expanding aneurysm were eventually followed by rupture. The defect was detected at open surgery, whereas no evidence of endoleak was found at preoperative computed tomography (CT) or angiogram. The defect was repaired by a relining procedure with an Excluder stent graft. The patient, however, died 3 weeks after admission.     

Symptomatic sac enlargement and rupture due to seroma after open abdominal aortic aneurysm repair with polytetrafluoroethylene graft: Implications for endovascular repair and endotension

OBJECTIVE: We report 5 patients in whom a symptomatic perigraft seroma developed within the aortic sac, without vascular endoleak, after open repair of an abdominal aortic aneurysm (AAA) with a polytetrafluoroethylene (PTFE) graft. We also discuss possible relationships of this phenomenon to endovascular repair of AAAs. PATIENTS AND METHODS: Over 18 years, 1156 patients underwent repair of an AAA by one of the authors (B.M.B.). Of these, 1084 underwent open repair, 256 with PTFE grafts. Five patients in the PTFE group (2.3%) returned at a mean of 4.5 years with acute abdominal or back pain and enlargement of the aortic sac. Mean diameter of the aneurysms was 5.9 cm preoperatively and 8.1 cm at readmission. There was no evidence of vascular endoleak on computed tomography scans, but 1 patient had a retroperitoneal hematoma. RESULTS: Laparotomy in 4 patients disclosed a seroma containing firm rubbery gelatinous material under tension, histologically identified as amorphous eosinophilic material containing thrombus and degenerate blood cells in all cases. Rupture of the sac was confirmed in the patient with a retroperitoneal hematoma. The sac contents were evacuated and the integrity of the underlying grafts and anastomoses was confirmed before sac reduction, with imbricating sutures, and closure was performed. One patient died at 8 months of an unrelated cause; the other 3 patients remain well at mean follow-up of 12 months. The fifth patient received conservative treatment and remains asymptomatic 3 years after acute presentation. CONCLUSIONS: These findings of sac enlargement without vascular endoleak after open AAA repair are reminiscent of sac enlargement in the absence of endoleak after endovascular AAA repair. This has been referred to as endotension. The comparatively benign outcome in 5 patients with symptomatic sac enlargement, including 2 patients with rupture, after open AAA repair provides data to support a circumspect approach to endotension, especially in patients with asymptomatic disease, which has been reported as occurring in almost half of patients who received a PTFE Excluder endograft.     

Rupture of abdominal aortic aneurysm previously treated by endovascular stentgraft

We describe a case of abdominal aortic aneurysm (AAA) with rupture 16 months after treatment by an endograft. A 76-year-old patient on Coumadin after aortic valve replacement had initially successful exclusion by stentgraft. There was no evidence of an endoleak seven months after stentgraft repair, although a computed tomography scan detected an enlargement of the aneurysm sac. Sixteen months after initial endograft surgery, rupture of the aneurysm occurred and we performed open emergency surgery. We treated the aneurysm by conventional technique, and the patient survived the rupture. This case emphasized the fact that patients after endograft AAA repair require a close follow-up. An expansion of the aneurysm sac after the procedure should signal failed exclusion, even if a computed tomography scan does not demonstrate an endoleak. Anticoagulation can be an important factor in failure after endoluminal graft treatment. Supravisceral aortic cross clamping is helpful in dealing with a stented aorta. (J Vasc Surg 1998;28:184-7.)     

Endoluminal stent grafting of the thoracic aorta: initial experience with the Gore Excluder

PURPOSE: The purpose of this study was to describe our experience with endoluminal graft repair of a variety of thoracic aorta pathologies with a commercially developed device currently under investigation. Our patient population included patients eligible for open surgical repair and those with prohibitive surgical risk. METHODS: From February 2000 to February 2001, endovascular stent-graft repair of the thoracic aorta was performed in 46 patients (mean age, 70 years; 29 male and 17 female patients) with the Gore Excluder. Twenty-three patients (50%) had atherosclerotic aneurysms, 14 patients (30%) had dissections, three patients (7%) had aortobronchial fistulas, three patients (7%) had pseudoaneurysms, two patients (4%) had traumatic ruptures, and one patient (2%) had a ruptured aortic ulcer. Patient characteristics, procedural variables, outcome, and complications were recorded. All patients were followed with chest computed tomographic scans at 1, 3, 6, and 12 months. Follow-up period ranged from 1 month to 15 months, with a mean of 8.5 months. RESULTS: All the procedures were technically successful. There were no conversions. Average duration of the procedure was 120 minutes. Average length of stay was 6 days, but most patients (64%) left the hospital within 4 days after endoluminal grafting. The overall morbidity rate was 23%. Two patients (4%) had endoleaks that necessitated a second procedure for successful repair. Two patients (4%) died in the immediate postoperative period. There were no cases of paraplegia. At follow-up examination, one patient had an endoleak found the day after the procedure and another patient had an endoleak 6 months after the procedure. Both cases were treated successfully with additional stent-grafts. There were no cases of migration. One patient died of a myocardial infarction 6 months after graft placement. In patients treated for aneurysm (n = 23), the aneurysm diameter ranged from 5.0 to 9.5 cm (mean, 6.8 cm). Residual sac measurements were obtained at 1, 6, and 12 months, with mean sac reductions of 0.59 cm, 0.77 cm, and 0.85 cm, respectively. In three cases, the sac remained unchanged, without evidence of endoleak. CONCLUSION: Thoracic endoluminal grafting with the Gore Excluder is a safe and feasible alternative to open graft repair and can be performed successfully with good results. Early data suggest an endoluminal approach to these disease entities may be favorable over classical resection and graft replacement.     

Abdominal aortic aneurysm size regression after endovascular repair is endograft dependent

OBJECTIVE: This study was performed to determine whether abdominal aortic aneurysm (AAA) regression is different with various endografts after endovascular repair. METHODS: A four-center retrospective review of size change after endovascular AAA repair was performed. Consecutive patients with at least 1-year follow-up and available imaging studies were included. Three hundred ninety patients received either the Ancure, AneuRx, Excluder, or Talent endograft. AAA size and endoleak status were recorded from computed tomography (CT) scans at the initial postoperative follow-up visit and at 1 and 2 years thereafter. AAA size was defined as the minor axis of the infrarenal aorta on the largest axial section on the two-dimensional CT scan. A change in AAA size of 0.5 cm or greater from baseline was considered clinically significant. The effect of initial size, endoleak, and type of endograft on AAA regression was analyzed. RESULTS: Mean baseline size was significantly greater with Talent endografts and smaller with Excluder endografts. Clinically significant regression in AAA size occurred in nearly three fourths of patients with Ancure and Talent endografts at 2 years. Regression in AAA size was less frequent with the AneuRx (46%) and Excluder (44%) devices. Initial size, endoleak, and endograft type were significant predictors of regression at multivariate analysis at 1 year. However, by 2 years only endograft type was still an independent predictor of AAA shrinkage. CONCLUSIONS: Long-term morphologic changes after endovascular aneurysm repair depend on endograft type.     

Sac enlargement due to seroma after endovascular abdominal aortic aneurysm repair with the Endologix PowerLink device

A patient who had undergone endovascular repair of an abdominal aortic aneurysm with the Endologix PowerLink bifurcated system presented with delayed aortic aneurysm enlargement due to assumed endotension. He was treated with aortic sac evacuation and wrapping of the endograft. This is the first report of endotension and aneurysm sac enlargement after implantation of the PowerLink endograft.     

Colonic necrosis subsequent to catheter-directed thrombin embolization of the inferior mesenteric artery via the superior mesenteric artery: A complication in the management of a type II endoleak

The optimal management of endoleaks after endovascular repair of abdominal aortic aneurysms remains to be established. In this report, we describe a persistent side-branch, or type II, endoleak 1 year after endograft implantation treated with catheter-directed embolization of the aneurysm sac and the inferior mesenteric artery via the superior mesenteric artery, with embolization agents including thrombin, lipiodol, and gelfoam powder. Shortly after the embolization procedure, colonic necrosis developed in the patient, manifested by peritonitis, which necessitated a partial colectomy. This case underscores the devastating complication of colonic ischemia as a result of catheter-directed embolization of the inferior mesenteric artery in the management of an endoleak.     

The significance and management of the leaking endograft.

Endoleak is the persistence of blood flow outside the lumen of an endograft, but within an aneurysm sac or adjacent vessel being treated by the graft. Diagnosis may be difficult, and treatment remains somewhat controversial. The purpose of this article is to discuss the clinical significance and appropriate management of endoleaks within the context of our current understanding of this phenomenon. The diagnosis of an endoleak can be made by conventional angiography, duplex ultrasound, intravascular ultrasound (IVUS), and computed tomography (CT) angiography. All of these modalities are effective, although CT angiography may be the most sensitive. Endoleaks can be categorized into 5 classes: (1) perigraft flow around the proximal end of the endograft; (2) perigraft flow around the distal end of the endograft; (3) flow through a defect in the body of the endograft; (4) flow between segments of a multicomponent endovascular graft; and (5) flow between arterial branches within an aneurysm sac. The first 4 classes have been shown to represent a clinical situation in which systemic arterial pressure is transmitted to an inadequately excluded aneurysm sac, placing the sac at risk of rupture. In contrast, branch-flow leaks do not appear to carry an increased risk of rupture, provided there is no increase in aneurysm sac diameter. However, an increase in the diameter of an aneurysm sac after endograft implantation may be a sign of occult endoleak, even if not visualized by current imaging techniques. Thus, we believe that collateral branch leaks with no associated aneurysm sac expansion may be observed with regular follow-up by CT angiography. All other endoleaks should be treated with adjunctive endovascular maneuvers or explanation of the endograft with standard open repair-in short, routine follow-up imaging on endografts to detect the presence of late endoleaks or aneurysm sac expansion.     

Infrarenal Abdominal Aortic Aneurysm Complicated by Persistent Endotension After Endovascular Repair: Report of a Case

Endoleak and endotension may prevent the successful exclusion of an aneurysm after endovascular aortic aneurysm repair (EVAR). The pressurization in the excluded aneurysm sac caused by endotension may lead to rupture of the aneurysm; however, the cause of endotension and its underlying mechanisms remain unclear. We report a case of infrarenal abdominal aortic aneurysm (AAA) complicated by persistent endotension after EVAR. Although no endoleaks were found on conventional double-phase computed tomographic scans, a thrombosed endoleak existed in the side branch and attachment site of the endograft. After treating the undetectable thrombosed endoleaks, physical examination revealed that the pressure of the excluded aneurysm had diminished, with shrinkage of the aneurysm. This case report suggests that a high-pressure undetectable type I or type II endoleak could be a major cause of endotension. Thus, postoperative evaluation of the attachment site of an endograft is important after EVAR.     

"Unpredictable" late rupture of an abdominal aortic aneurysm after bifurcated Ancure endograft repair

The goal of endovascular repair of an abdominal aortic aneurysm is to exclude the aneurysm from systemic arterial pressure, thereby preventing rupture. However, the long-term durability of endovascular repair continues to be in question, as aneurysm rupture after endovascular repair continues to be reported. We report the case of an 89-year-old patient who underwent endovascular repair of a 7.1-cm abdominal aortic aneurysm with an Ancure endograft 5 years earlier. Despite close follow-up and a shrinking aneurysm sac on annual contrast-enhanced computed tomography, he presented with aneurysm rupture and a new proximal type I endoleak. The endoleak and rupture were successfully repaired with endovascular placement of a main body extension.