Mid-term results of patients undergoing endovascular aortic aneurysm repair.

BACKGROUND: The utilization of endovascular aneurysm repair (EAR) is increasing significantly; however, few papers have outlined mid-term outcomes. METHODS: Patients undergoing EAR with an AneuRx endograft between September 1997 and May 2001 were evaluated. Mean follow-up was 20.7 +/- 11.9 (SD) months. RESULTS: In all, 101 EAR devices were successfully deployed in 105 attempts. Four open conversions (2 acute, 2 delayed) were performed for complications of EAR. Technical, clinical, and 1 to 3 year continuing success rates were 75%, 73%, and 78% to 83%. When divided by the median date, significantly fewer patients in the later group required secondary procedures compared with the early group. Vascular insufficiency occurred in 12 patients; 11 were treated with a secondary procedure. For 9 type I and 9 type II persistent endoleaks, secondary procedures were attempted and successful in 10 patients. Of successful EAR deployments, including secondary interventions, 85% demonstrated no persistent leak, rupture, increase in aneurysm size, or migration at most recent follow-up. CONCLUSIONS: EAR is successful in selected individuals; however, continuing follow-up is of paramount importance.

Secondary procedures after endovascular aortic aneurysm repair.

PURPOSE: The purpose of this study was to evaluate the incidence, distribution, and indications of secondary procedures after endovascular aortic aneurysm repair (EAR). METHODS: At a single institution, 179 patients underwent EAR with four different endografts (AneuRx, n = 117; Zenith, n = 49; Ancure, n = 12; and Talent, n = 1). The vascular section database was queried for patients who needed secondary procedures after the original EAR. The mean time from EAR to the termination of the study was 27.0 +/- 16.7 months. Type I or III endoleaks were treated aggressively. Type II endoleaks were treated only in the presence of aneurysm expansion. RESULTS: Thirty-five (35/179; 19.6%) secondary procedures were performed in 32 patients. Indications for secondary procedures included 14 limb occlusions or stenoses (40.0%), 13 endoleaks (37.1%), six endograft migrations (17.1%), one delayed aneurysm rupture (2.8%), and one device malfunction (2.8%). Seven of the 10 early (<90 days) limb failures (70%) occurred within the first 60 patients. At that time, a protocol with aggressive external iliac artery evaluation was adopted. In the next 125 patients, the rate of early limb occlusion or stenosis was 2.4% (P =.025, with Fisher exact test). Distribution of secondary procedures included 23 endoluminal interventions (65.7%; angioplasty +/- stent placement, thrombolysis, endocuff placement, embolization), eight traditional peripheral procedures (22.9%; femoral-femoral bypass, thrombectomy), two laparoscopic interventions (5.7%; inferior mesenteric artery ligation), and two laparotomies (5.7%; delayed conversions). Interventions for limb occlusion or stenosis occurred earliest (3.5 +/- 5.4 months; P <.05, with analysis of variance), followed by treatment of endoleaks (14.3 +/- 12.9 months) and migration (27.5 +/- 10.4 months). The one delayed rupture occurred at 15.3 months. CONCLUSION: Secondary procedures after EAR are common. Reinterventions can be grouped temporally on the basis of indication. Treatment for limb ischemia is predominately early (>/=3 months), whereas treatment for endoleaks occurs at approximately 1 year and interventions for migration predominate after 2 years.

Endograft migration one to four years after endovascular abdominal aortic aneurysm repair with the AneuRx device: a cautionary note.

BACKGROUND: Positional stability of the endograft is essential for long-term durability after endovascular abdominal aortic aneurysm repair (EAR). However, the cumulative risk of delayed endograft migration has been sparsely reported. METHOD: A total of 91 patients studied underwent EAR with the AneuRx endograft with a minimum 1 year from implantation. Data from a prospective database were assessed for proximal endograft migration, defined as > or = 5 mm change from the initial endograft position. Multiple anatomic characteristics were also examined. Sixty-nine patients were alive, with complete follow-up at 1 year, with a mean time from implantation of 33.2 +/- 1.1 months. Data are mean +/- SEM. RESULTS: Endograft migration occurred in 15 patients, giving a cumulative event rate of 7.2% (5/69) at 1 year, 20.4% (10/49) at 2 years, 42.1% (8/19) at 3 years, and 66.7% (2/3) at 4 years post-EAR (P =.01). Although the initial aortic neck diameter did not differ between the groups (21.5 +/- 0.6 mm vs 21.8 +/- 0.3 mm, P =.61), significant (P <.05), late aortic neck enlargement was seen in patients with migration (25.0 +/- 1.6 mm, 26.2 +/- 1.2 mm, and 27.0 +/- 1.0 mm at 1,2, and 3 years, respectively) but not in nonmigrators. Regression analysis demonstrated a statistically significant (P <.05) correlation between endograft oversizing and late aortic neck dilation. Overall migration risk was 29.2% in patients oversized >20% and 18.6% in patients oversized < or = 20%. Aortic neck angulation (23.4 +/- 6.6 degrees vs 23.5 +/- 3.3 degrees, P =.99), aortic neck length (25.9 +/- 2.5 mm vs 27.0 +/- 1.6 mm, P =.74), initial endograft/aortic neck overlap (18.6 +/- 2.6 mm vs 19.4 +/- 1.4 mm, P =.80) and size of abdominal aortic aneurysm (55.5 +/- 1.5 mm vs 54.9 +/- 1.4 mm, P =.84) were similar between migrators and nonmigrators, respectively. Secondary endovascular treatment with aortic cuffs was required in five patients with device migration. CONCLUSIONS: Device migration after EAR with the AneuRx endograft occurred with significant frequency, the incidence of which increased with the length of follow-up. Late aortic neck dilation was significantly associated with migration. Oversizing of the endograft of >20% may accelerate this late aortic neck dilation. However, the etiologies of endograft migration were likely multifactorial, as the majority (8/15) of patients experiencing migration were oversized <20%. Although endovascular repair of these migrations is usually possible, the long-term durability of these secondary procedures is unknown. Careful surveillance for this endograft failure mode must be an essential component of post-EAR follow-up.

Does ASA classification impact success rates of endovascular aneurysm repairs?

The purpose of this study was to evaluate the technical success, clinical success, postoperative complication rate, need for a secondary procedure, and mortality rate with endovascular aneurysm repair (EAR), based on the physical status classification scheme advocated by the American Society of Anesthesiologists (ASA). At a single institution 167 patients underwent attempted EAR. Query of a prospectively maintained database supplemented with a retrospective review of medical records was used to gather statistics pertaining to patient demographics and outcome. In patients selected for EAR on the basis of acceptable anatomy, technical and clinical success rates were not significantly different among the different ASA classifications. Importantly, postoperative complication and 30-day mortality rates do not appear to significantly differ among the different ASA classifications in this patient population.

Endovascular exclusion of saccular AAAs using "stacked" AneuRx aortic cuffs.

PURPOSE: To show that AneuRx aortic cuffs might be used in a "stacked" configuration to effectively treat saccular abdominal aortic aneurysm (AAA). METHODS: In a recent 1-year period, 147 patients underwent endovascular AAA repair. Of these, 5 (4 men; mean age 61.6 years, range 55-69) had saccular AAAs with a mean diameter of 3.7 +/- 0.2 cm (range 3.0-4.7). AneuRx aortic cuff prostheses (3.75-cm length) were deployed sequentially in these 5 patients via a right femoral approach; the devices were overlapped approximately 1.5 to 2.0 cm until complete exclusion of the aneurysm was achieved. Endograft surveillance was performed using computed tomography at 4 weeks postoperatively and then every 6 months. RESULTS: Successful exclusion of the saccular infrarenal aortic aneurysms was achieved in all 5 patients using 2 or 3 "stacked" stent-graft extensions. Four of the 5 procedures were performed under spinal anesthesia; the average procedural time was 96 +/- 41 minutes. The average hospital length of stay was 1.6 days; no major morbidity or mortality was encountered. There were no early or late endoleaks, aneurysm expansion, or device migration over a follow-up that ranged to 12 months. CONCLUSIONS: Saccular AAA provides ideal anatomy for endovascular repair with a "tube" endograft. "Stacked" aortic cuffs create a customized stent-graft that is not otherwise commercially available.

Aortic neck angulation predicts adverse outcome with endovascular abdominal aortic aneurysm repair.

BACKGROUND: Significant aortic neck angulation may predispose to suboptimal outcome after endovascular abdominal aortic aneurysm (EAAA) repair. However, the definition of "significant" neck angulation and its correlation with adverse outcome are poorly characterized. METHODS: Prospectively collected data on 148 consecutive EAAA repairs performed between December 1995 and January 2001 were supplemented with retrospective review of charts and radiographs. Aortic neck angulation was measured from arteriograms or three-dimensional computed tomography scanning reconstructions. Patients were excluded (n = 24) if radiographs were unavailable for review. Because of a paucity of severe aortic neck angulation in other endograft groups, only patients treated with a modular bifurcated device (Medtronic) (n = 81) were included in the final analysis. Mean time from implantation was 26.6 +/- 9.2 months. RESULTS: The risk of a patient experiencing one or more adverse events was 70%, 54.5%, and 16.6% in those with severe (>or=60 degrees, n = 10), moderate (40 to 59 degrees, n = 11), and mild (<40 degrees, n = 60) aortic neck angulation, respectively (P =.0003). Adverse events included death within 30 days (20% vs 0%, P =.0007), acute conversion to open repair (20% vs 0%, P =.0007), aneurysm expansion (9.1% to 20% vs 1.7%, P =.034), device migration (20% to 30% vs 3.3%, P =.013), and type I endoleak (23.8% vs 8.3%, P =.033), all occurring with significantly greater incidence in patients with moderate or severe aortic neck angulation when compared with those with mild angulation, respectively. Aortic neck length and diameter, age, and medical comorbidities were not significantly different between groups. CONCLUSION: Aortic neck angulation appears to be an important determinant of outcome after EAAA repair. Although patients with mild angulation (<40 degrees) had favorable outcomes in this series, those with moderate (40 to 59 degrees) or severe angulation (>or=60 degrees) had a 54% to 70% risk of one or more adverse events. Importantly, these outcomes occurred in spite of an adequate length (>2 cm) of proximal aortic neck. On the basis of these data, great caution should be exercised in recommending EAAA repair for patients with aortic neck angulation >or=40 degrees.

Management of suspected hemodialysis graft dysfunction: usefulness of diagnostic US.

PURPOSE: To evaluate the role and usefulness of diagnostic ultrasonography (US) in the assessment of hemodialysis access grafts with an intermediate probability of graft malfunction. MATERIALS AND METHODS: One hundred forty-seven complete US examinations were performed in 91 patients. Average volume of flow, peak systolic velocity, and diameter of residual lumen were recorded. Patients were referred by the nephrology department when clinical findings were suggestive, but not obviously, of graft malfunction. Study results were deemed normal if flow volume exceeded 1,300 mL/min without significant visualized stenosis of 50% of the diameter or greater or if flow approached 1,300 mL/min without peak systolic velocity greater than 400 cm/sec. RESULTS: Of the 147 examinations, 49 (33%) had normal results, seven (5%) showed thrombosis at examination, and 91 (62%) had evidence of at least one significant visualized stenosis or diffuse notable degree of thrombus. Three patients with normal results required fistulography within 90 days, one for thrombosis. In the 91 studies with abnormal results, 69 patients underwent fistulography; results in 63 showed agreement, and three showed false-positive results. More central venous stenoses were found at fistulography than at US. CONCLUSION: US is a useful and reliable first step in managing clinically suspected hemodialysis graft stenosis. One-third of the studies showed no significant stenosis and did not require angiographic evaluation. US should be the initial study in patients suspected of having hemodialysis access dysfunction without exceptional evidence of stenosis.