Surveillance of small aortic aneurysms does not alter anatomic suitability for endovascular repair

OBJECTIVE: Small abdominal aortic aneurysms (AAAs; 4-5.4 cm) are more likely to be suitable for endovascular aneurysm repair (EVAR) than large aortic aneurysms (>5.5 cm). The purpose of this study was to determine whether small AAA growth is associated with the development of morphologic characteristics that decrease eligibility for EVAR. METHODS: We studied 54 patients who underwent 2 or more computed tomography scans with 3-dimensional reconstruction during surveillance of small AAAs. Morphologic aortic aneurysm features and changes were measured according to Society for Vascular Surgery reporting standards. Suitability for EVAR was determined by neck anatomy (diameter, length, and angulations), iliac artery morphology, and total aortic aneurysm angulation and tortuosity. RESULTS: The median age of the study cohort was 73 years (interquartile range [IQR], 65-77 years). The median follow-up period was 24 months (IQR, 15-36 months). The median small AAA diameter increased from 44.5 mm (IQR, 41-48 mm) to 48.9 mm (IQR, 45.7-52.0 mm). The median aortic neck diameter increased from 23.0 to 24.0 mm (P = .002), whereas median neck length decreased from 26.5 to 20.0 mm (P = .001). Aortic aneurysm median tortuosity index increased from 1.09 to 1.11 (P = .05). No significant changes in iliac artery morphology occurred. Overall, the anatomic suitability for endovascular repair did not significantly change during the study period (74% vs 69%; McNemar test; P = .25). CONCLUSIONS: Changes in aortic morphology are frequently associated with small AAA growth at mid-term follow-up, but such changes are minor and do not affect overall anatomic suitability for EVAR. These data reveal that continued surveillance of small AAAs does not threaten the window of opportunity for EVAR.     

Anatomic suitability of ruptured abdominal aortic aneurysms for endovascular repair

Mortality from ruptured abdominal aortic aneurysms (rAAAs) remains high despite improvements in anesthesia, postoperative intensive care, and surgical techniques. Recent small series and single-center experiences suggest that endovascular aneurysm repair (EVAR) for rAAAs is feasible and may improve short-term survival. However, the applicability of EVAR to all cases of rAAA is unknown. The purpose of this study was to investigate the anatomical suitability of ruptured aneurysms for EVAR as determined by preoperative cross-sectional imaging. A contemporary consecutive series of rAAAs presenting to a tertiary academic center was retrospectively reviewed. Preoperative radiographic imaging was reviewed and assessed for endovascular compatibility based on currently available EVAR devices. Patients with aneurysm morphology demonstrating neck diameter >32 mm, neck length <10 mm, neck angulation >60 degrees, severe iliac tortuosity, or external iliac diameter <6 mm were deemed noncandidates for EVAR. Forty-seven rAAAs were treated over a 10-year period, with 47% of patients presenting with free rupture and 60% of patients transferred from outside hospitals. Five (11%) patients were treated with EVAR, all over the past 2 years, while the remaining 42 patients underwent open repair. Preoperative imaging was available for review in 43 (91%) patients, and morphological measurements indicated that 49% would have been candidates for EVAR with currently available devices. Criteria precluding EVAR in this cohort were inadequate neck length in 73%, unsuitable iliac access in 23%, large neck diameter in 18%, and severe neck angulation in 14%. Overall 30-day mortality was 34%, and 1-year mortality was 42%. Candidates for EVAR were more likely than non-EVAR candidates to be male (95% vs. 68%, p = 0.046) and to have smaller sac diameters (7.0 vs. 8.5 cm, p = 0.02) and longer neck lengths (24.1 vs. 8.6 mm, p < 0.0001); less likely to have a >60 degree angulated neck (10% vs. 45%, p = 0.0002), larger external iliac diameter (8.9 vs. 7.3 mm, p = 0.015), and less blood loss during surgical repair (2.4 vs. 6.0 L, p = 0.02); and more likely to be discharged home (71% vs. 25%, p = 0.05). There were no differences in 30-day, 1-year, or overall mortality between candidates for EVAR and noncandidates. Only 49% of patients with rAAAs in this consecutive series were found to be candidates for EVAR with conventional stent-graft devices. Differences in demographics, aneurysm morphology, and outcomes between candidates and noncandidates undergoing open repair suggest that differential risks apply to ruptured aneurysm patients. Protocols and future reports of EVAR for rAAAs should be tailored to these results. Device and technique modifications are necessary to increase the applicability of EVAR for rAAAs.     

Aortic necks of ruptured abdominal aneurysms dilate more than asymptomatic aneurysms after endovascular repair

BACKGROUND: Endovascular repair of abdominal aortic aneurysm (AAA) is increasingly used. We evaluated if a difference exists in the rate of change of the aortic neck diameter between non-ruptured and ruptured AAAs after endovascular aneurysm repair (EVAR). METHODS: Details of patients undergoing elective (group I) and emergency (group II) EVAR using Talent stents between October 1999 and September 2005 were reviewed. Top neck diameters were prospectively recorded on the hospital database from computed tomography scans preoperatively and at 1, 3, 12, and 24 months postoperatively. The aortic neck diameter rate of change was calculated for each group. RESULTS: Endovascular repair was performed on 110 elective and 41 emergency patients, of which 100 (80 male) elective and 29 (26 male) emergency patients were included in this analysis. Mean age was similar in each group. Stents were oversized by 20.9% +/- 13.6% in group I and by 24.7% +/- 16.3% in group II (P = .37). The preoperative mean proximal aortic neck was larger in group II (25.0 +/- 3.3 mm vs 23.5 +/- 2.8 mm; P = .029). The growth rate of the top neck diameter was significantly greater at 12 months (1.48 +/- 2.4 mm/year vs 3.89 +/- 6.24 mm/year; P = .04) and 24 months (.99 +/- 1.1 mm/year vs 2.61 +/- 3.3 mm/year; P = .04) in group II than in group I. A decreasing sac size was found in 68.2% of patients whose neck dilated. The complication rate was similar in each group. CONCLUSION: Aneurysm necks in patients with ruptured aneurysms are larger and dilate at a greater rate than those with nonruptured aneurysms. The accelerated rate of expansion in some patients must be borne in mind during follow-up and in secondary endovascular interventions and conversion to open surgery.     

Influence of age, aneurysm size, and patient fitness on suitability for endovascular aortic aneurysm repair

Prior to approval by the U.S. Food and Drug Administration of larger endografts (main body diameters up to 36 mm), small abdominal aortic aneurysms (AAAs, <5.5 cm) were shown to be more suitable for endovascular repair (EVAR) than large AAAs (> or =5.5 cm). The purpose of this study was to assess changes in EVAR suitability with the potential use of larger endografts in unselected consecutive patients. The influence of age, aneurysm size, and patient fitness on EVAR suitability was also assessed. We studied 186 male patients referred for evaluation of nonruptured AAAs who underwent contrast-enhanced computed tomographic scans with three-dimensional reconstructions. Morphologicall AAA features and neck characteristics were measured according to Society for Vascular Surgery reporting standards to determine EVAR suitability. Patient fitness for repair was assessed using the customized probability index, a validated fitness score for vascular surgery procedures. Suitability for EVAR was determined by neck anatomy, iliac artery morphology, and total aortic aneurysm angulation and tortuosity according to the clinicians' experience and current practice. The median age of the study cohort was 72 years (interquartile range [IQR] 65-79 years). The median maximum AAA diameter was 5.4 cm (IQR 4.1-5.9). Median fitness score was +7 (IQR -7 to +14). EVAR suitability for large AAAs significantly increased with larger endografts (35-63%, p<0.001). Changes in EVAR suitability for small AAAs were not significant (69-75%, p=0.06). Maximum AAA diameter was not an independent predictor for EVAR suitability with larger endografts after adjusting for neck anatomy. Aortic neck length (odds ratio [OR]=1.2, 95% confidence interval [CI] 1.1-1.2) and diameter (OR=0.78, 95% CI 0.63-0.96) were the only independent predictors for EVAR suitability with larger endografts. Age, AAA size, and fitness did not differ between patients suitable and unsuitable for EVAR with larger endografts. In conclusion, introduction of larger endografts (up to 36 mm in main body diameter) in the United States has resulted in significantly increased anatomic suitability for EVAR for large AAAs. Conversely, suitability has not significantly changed for small AAAs. Overall, EVAR suitability is not influenced by age, aneurysm size, or patient fitness.     

Endovascular aneurysm repair with a bifurcated endovascular graft at a primary referral center: influence of experience, age, gender, and aneurysm size on suitability

OBJECTIVE: The purpose of this study was to assess the suitability for endovascular repair of abdominal aortic aneurysm (EVAR) in an unselected patient population. PATIENTS AND METHODS: Between February 1999 and May 2002 all consecutive patients with a nonemergent abdominal aortic aneurysm (AAA) were prospectively examined with contrast material-enhanced spiral computed tomography (CT). Those patients probably suitable for EVAR on the basis of CT findings underwent calibrated angiography. A panel of radiologists and vascular surgeons reviewed the clinical data and vascular anatomy, and decided on the appropriateness of EVAR with the bifurcated Zenith AAA endovascular graft. RESULTS: One hundred seven patients were included. Fifty-six patients (52%) had one or more contraindications for EVAR. Unsuitability was most frequently (88%) related to the proximal neck. Inadequate neck length was the most common specific reason. Inadequate iliac anatomy was the reason for unsuitability in 59% of patients. The rate of unsuitability decreased from 61% during the first half of the study to 40% during the second half (P =.03) Unsuitability was equal between men and women. Age and maximum diameter did not differ between candidates and noncandidates. CONCLUSION: Almost half (48%) of patients with an infrarenal AAA referred to a primary referral center are suitable for EVAR with the bifurcated Zenith AAA endovascular graft. Neck anatomy was the most frequent reason for rejection. Rate of suitability increased over time, probably as a result of increasing experience. Suitability was not influenced by gender, age, or aneurysm size.     

Does the presence of an iliac aneurysm affect outcome of endoluminal AAA repair? An analysis of 336 cases.

OBJECTIVE: To determine whether the presence of an iliac aneurysm compromises outcome of endovascular exclusion of AAA and to ascertain the fate of the iliac aneurysmal sac. PATIENTS AND METHODS: Between April 1997 and March 2001, data on 336 consecutive patients undergoing endovascular repair for AAA were entered in a prospective database. Suitability for endovascular repair was assessed by preoperative contrast-enhanced computed tomography. A maximum common iliac artery (CIA) diameter > or = 20 mm was defined as iliac aneurysm. Patients with and without iliac aneurysms were compared to early (immediate conversion or perioperative death) and late failure (increase in aneurysm diameter or persisting graft-related endoleak, or late AAA rupture or conversion). RESULTS: Fifty-nine patients (18%) had iliac aneurysms, 19 were bilateral, for a total of 78 aneurysmal iliac arteries (median diameter 23 mm; range 20-50 mm). A distal seal was achieved by landing in 33 external iliac arteries, in 20 ectatic CIAs, and in 25 normal CIAs. Operating time differed significantly between patients with and without CIA aneurysms (153 +/- 71 vs 123 +/- 55 min, p = 0.0001), whereas no statistically significant differences were found with respect to early and late failure (2% vs 3%, p = 0.5 and 14% vs 8%, p = 0.11, respectively). There were no cases of buttock or colon necrosis. At a median follow-up of 14 months (range 0-46; i.q.r. 7-27 months) common iliac diameter decreased > or = 2 mm in 49 cases, remained stable in 25, and increased > or = 2 mm in 3. CONCLUSION: The presence of iliac aneurysm rendered endoluminal AAA repair more complex but did not affect feasibility and long-term outcome of the procedure. In our experience internal iliac exclusion was never associated with significant morbidity. These data may be useful when considering endovascular repair in high-risk patients with challenging anatomy.     

腹主动脉瘤腔内修复术中髂动脉瘤的处理策略

目的:探讨腹主动脉瘤合并髂动脉瘤的腔内修复术(EVAR)方法。方法:回顾性分析2007年8月—2014年3月35例腹主动脉瘤合并髂动脉瘤行EVAR术患者资料,其中9例合并单侧髂内动脉瘤,1例合并双侧髂内动脉瘤,14例合并单侧髂总动脉瘤(直径18 mm),11例合并双侧髂总动脉瘤,所用腔内技术包括栓塞髂内动脉瘤后覆盖,髂内动脉瘤单纯覆盖,"喇叭口"支架,以及"三明治"技术重建一侧髂内动脉等。结果:所有腔内技术均获得成功,手术时间(125±40)min,出血量(173±65)m L。术中发现内漏8例(22.9%),其中I型内漏4例(近端2例,远端2例)均经球囊扩张后内漏消失,III型内漏1例,经扩张及部分加弹簧圈栓塞后内漏消失,II型内漏2例及IV型内漏1例,均未予处理。35例术后随访6~60个月,无动脉瘤破裂,2例术后6个月发现腹主动脉瘤体增大,造影确诊远端I型内漏,经弹簧圈栓塞后内漏消失,其余33例瘤体直径无增大。结论:对于合并髂动脉瘤的腹主动脉瘤患者,有效处理髂内动脉,然后根据髂总动脉直径选择合适的治疗方法可以达到理想的近期效果。     

Most patients with abdominal aortic aneurysm are not suitable for endovascular repair using currently approved bifurcated stent-grafts

Strict morphologic criteria must be used for patient selection to achieve durable success with endovascular aortic aneurysm repair (EVAR). The goal of this study was to assess morphologic suitability (MS) of abdominal aortic aneurysms (AAAs) for 2 currently approved bifurcated stent grafts and identify reasons for exclusion from EVAR. The authors reviewed the electronic charts of 1,795 consecutive patients who were diagnosed as having AAA between January 1999 and July 2001 at their institution. Three hundred and twenty patients had an AAA with a diameter of > or = 5.0 cm, measured on computed tomography (CT). The records of 301 patients, 254 men, 47 women, with a mean age of 74 years were available for review, and these patients constituted the study cohort. Criteria used for MS included a proximal neck length > or = 15 mm; neck diameter between 18 and 26 mm; neck angulation < or = 60 degrees ; common or external iliac artery (CIA or EIA) diameters of 7-16 mm and 8-13 mm, respectively, for AneuRx (Medtronic Ave, Santa Rosa, CA) and Ancure (Guidant Cardiac and Vascular Division, Menlo Park, CA) bifurcated grafts. AAAs were suitable for AneuRx device in 14% of patients (43 of 301; 95% CI = 11-19%) and for Ancure in 5% (16 of 301; 95% CI = 3.1-9%). The main reason for exclusion was an inadequate proximal aortic neck (73%). The neck was too short in 49.5%, too wide in 64% and badly angulated in 12% of the patients. Iliac artery morphology precluded EVAR with AneuRx and Ancure devices in 52% and 80%. Both CIAs were too wide for EVAR in 43% and 77%, respectively. When iliac artery diameter < or = 20 mm was accepted, iliac suitability for AneuRx increased from 49% to 70% and overall suitability increased from 14% to 20%. When more permissive criteria were used for MS (neck length > or = 10 mm, neck diameter < or = 30 mm, CIA < or = 20), 39% of patients became candidates for EVAR. More than three fourths of the patients with an AAA > or = 5.0 cm in size, seen in a tertiary referral center, are morphologically not suitable for EVAR using 2 currently approved bifurcated endografts. The main reasons for exclusion are a short or wide proximal aortic neck. Considerable changes in size of the devices and in proximal attachment techniques have to occur before most AAAs will be suitable for EVAR.     

Endovascular repair of small abdominal aortic aneurysms: a paradigm shift?

Recent reports have documented poor long-term results following endovascular aneurysm repair (EVAR) of large abdominal aortic aneurysms (AAA). EVAR of small AAAs may result in improved long-term results compared to large AAAs. It is not known whether the frequency of anatomic suitability for EVAR is increased for small compared to large AAAs. This study compared the anatomic suitability of large and small AAAs for EVAR in an unselected patient population. Radiology reports for all computed tomography (CT) scans in a single hospital over a recent 3-year period were reviewed. AAAs diagnosed by contrasted CT scans with cuts >7 mm were excluded. Suitability for EVAR was determined by neck diameter, length, and angulation. In addition, iliac diameters and common iliac distal landing zone lengths were determined. Computerized 3-dimensional (3D) reconstruction was used to measure neck angulation and total aortic tortuosity. One hundred ninety-one patients were found to have AAAs with adequate CT scans for evaluation. Suitability for EVAR was highest in patients with AAA diameters of 3-4 cm and declined with increasing size of the AAA. Dividing AAAs into sizes greater than or less than 5.5 cm revealed that small AAAs had significantly longer necks, less neck angulation, longer common iliac landing zones, and less total aortic tortuosity. Multivariable analysis revealed that maximal aortic diameter was the only independent predictor of suitability for EVAR (p = 0.005, odds ratio 1.67, CI 95% = 1.17 to 2.38). The odds ratio predicts that with each 1 cm increase in size, the likelihood of suitability decreased by 5.3-fold. Small AAAs have less complex anatomy with longer aortic necks, less neck angulation, and less tortuosity. The poor outcomes following the treatment of large AAAs is thought to be due to complex anatomy. EVAR of less anatomically challenging small AAAs may improve long-term outcomes.     

解剖条件复杂的肾下型腹主动脉瘤的腔内治疗

目的 探讨腔内修复术治疗复杂解剖条件肾下型腹主动脉瘤的安全性和有效性.方法 对2003年1月至2011年3月接受经股动脉植入分体式覆膜支架治疗解剖条件复杂的48例腹主动脉瘤患者的临床资料进行回顾性分析.男性37例,女性11例;年龄50～81岁,平均71.4岁.其中近端短瘤颈(＜15 mm) 14例,近端瘤颈成角大(＞60°)13例,复杂髂动脉解剖者21例,其中髂动脉严重扭曲者15例,髂动脉狭窄(直径＜7 mm)者6例.结果 所有病例治疗均获成功,术中无中转开腹手术者,围手术期生存率100％.40例患者获得随访,随访时间4-122个月,平均63个月,死亡2例,均为心脑血管意外,其余生存良好,累积生存率95.8％.Ⅰ型内漏2例,其中1例2周后消失,1例长期存在,随访过程中未发现新发内漏、支架移位或堵塞、瘤体扩大或瘤体破裂等并发症;2例封堵一侧大部分肾动脉的患者恢复良好,术后未出现肾功能不全.结论 腔内修复术治疗复杂解剖条件肾下型腹主动脉瘤安全、有效.随着经验的不断积累,腔内修复术在治疗解剖条件复杂的肾下型腹主动脉瘤中将发挥更重要的作用.     

Aneurysm Diameter and Proximal Aortic Neck Diameter Influence Clinical Outcome of Endovascular Abdominal Aortic Repair: A 4-Year EUROSTAR Experience

Our objective was to evaluate the effect of preoperative aneurysm and aortic neck diameter on clinical outcome after infrarenal abdominal endovascular aneurysm repair (EVAR). Data of patients in the European Collaborators Registry on Stent-Graft Techniques for Abdominal Aortic Aneurysm Repair (EUROSTAR) registry base who underwent EVAR with Talent stent grafts were analyzed. Patient characteristics and clinical outcomes were compared among four groups defined by preoperative abdominal aortic aneurysm (AAA) and proximal aortic neck diameter: A, AAA ≤60 mm and neck ≤26 mm; B, AAA >60 mm and neck ≤26 mm; C, AAA ≤60 mm and neck >26 mm; and D, AAA >60 mm and neck >26 mm. Over a 7-year period, 1,317 patients underwent EVAR. Patients in groups B and D were significantly older and had a higher American Society of Anesthesiologists score compared with groups A and C (p=0.002 and 0.003, respectively). Mortality rate was highest in group D (p=0.002), as were rupture and conversion rates (p=0.015 and 0.037, respectively). This study demonstrates that patients with an AAA >60 mm and a proximal aortic neck >26 mm have worse clinical outcome after EVAR. Presented at the Fifteenth Annual Winter Meeting of the Peripheral Vascular Surgery Society, Steamboat Springs, CO, January 28-30, 2005.     

Ruptured abdominal aortic aneurysm: endovascular repair is feasible in 40% of patients.

INTRODUCTION: Open repair of ruptured abdominal aortic aneurysm (rAAA) still has a high mortality. Endovascular aortic repair (EVAR) may be the way to improve survival rates. However, it is not clear how many patients with rAAA will be suitable for acute EVAR. METHODS: Between October 2000 and April 2002 all patients with acute symptomatic or ruptured AAA were assessed for EVAR on an intention-to-treat basis with emergency computed tomographic angiography (CTA). Patient and logistic characteristics were analysed. We used two commercially available aorto uni-iliac devices with a maximum proximal diameter of 28 and 34 mm. RESULTS: Five out of 26 patients were excluded for CTA and EVAR because of severe and persistent hypotension (3 pts) or logistic reasons (2 pts, both eligible). Twelve patients were found not eligible for EVAR due to unsuitable infrarenal aortic neck length (3 pts), neck diameter (1 pt) or a combination of both (8 pts). The remaining six patients were treated with EVAR. After 6 months no graft failure or aneurysm related deaths were recorded in the EVAR group. CONCLUSION: A total of 28% of patients with symptomatic or ruptured AAA was treated with EVAR. A potential 42% of patients could have been suitable for EVAR, if the correct devices had been in stock and all patients had been properly assessed.     

The midterm experience of tapered stent grafts in the endovascular management of iliac artery aneurysms with unfavorable anatomy

We report our experience and the midterm results of a modern technique for endovascular management of isolated iliac artery aneurysms (IAAs) with unfavorable neck anatomy, which involves the inversion of an iliac leg of a Zenith stent graft. Patients who underwent endovascular IAA repair from 2002 to 2010 were reviewed. A total of 12 patients, with a mean age of 77.6 years, underwent endovascular repair of 13 IAAs. Mean size of the aneurysms was 54.6 mm (range 34-133 mm). Mean proximal neck diameter was 18 mm (range 15-22 mm). In 7 patients, the length of the proximal neck was <15 mm (10-14 mm). Only 1 patient developed thrombosis of the stent graft immediately after the operation. Patients were followed up for a mean of 31.5 months (range 18-72 months). Our midterm results demonstrate the durability of this technique in the management of iliac aneurysms with unfavorable anatomy.     

Is three-dimensional computed tomography reconstruction justified before endovascular aortic aneurysm repair?

OBJECTIVES: The endovascular management of abdominal aortic aneurysm (AAA) relies on accurate preoperative imaging for proper patient selection and operative planning. Three-dimensional (3-D) computed tomography (CT) with reformatted images perpendicular to blood flow has gained popularity as a method of AAA assessment and image-based planning before endovascular aneurysm repair (EVAR). The current study was undertaken to determine the interobserver agreement of AAA measurements obtained with axial CT and reformatted 3-D CT and to compare the consistency of the 2 methods in selecting patients for EVAR. METHODS: Eight observers assessed the axial CT and reformatted 3-D CT scans for 5 patients with AAAs to determine whether the patients were candidates for EVAR. 3-D CT with multiplanar reformatted images was performed by Medical Media Systems (MMS). Each observer measured the length and diameter of the proximal neck, maximal AAA, aortic bifurcation, common iliac diameter, and aortic angulation. The proximal neck and common iliac arteries were also assessed for thrombus, calcification, and tortuosity. Agreement of the measurements on axial CT scans was compared with those on MMS CT scans by calculating the kappa statistic. Complete agreement was defined as kappa = 1.0. The limits of agreement between observers were also calculated. RESULTS: The cumulative interobserver agreement of MMS CT scans (kappa =.81) was greater than for axial CT scans (kappa =.59). The kappa value for each of the diameter measurements was greater with the MMS CT scans. In 79% of cases the observers' measurements were less than 2 mm from the mean with MMS CT, compared with 59% for axial CT. The kappa value for deciding whether a patient was an endograft candidate on the basis of aortic neck was greater with the MMS CT (0.92 vs 0.63). The limits of agreement between observers were also better with the MMS CT. CONCLUSIONS: The interobserver agreement in planning EVAR is significantly better with MMS CT compared with traditional axial CT. The routine use of MMS CT appears justified before EVAR to improve the accuracy and consistency of patient selection.     

An intention-to-treat by endovascular repair policy may reduce overall mortality in ruptured abdominal aortic aneurysm

OBJECTIVE: The use of endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (AAA) has been restricted to a small number of specialized units on a selected group of patients. The aim of this study is to assess if the overall mortality in these patients with ruptured AAA may be reduced in a unit where all patients with ruptured AAA are considered first for EVAR. METHODS: During a 24-month period beginning in July 2002, 51 patients admitted with ruptured AAA were considered for EVAR as the treatment of choice and comprised the study group. EVAR was performed in 17 patients. Open repair was performed in 34 patients: 13 patients had hemodynamic instability and 16 patients had an unsuitable aortic neck anatomy. The study group was compared with a historical control group of 41 patients with ruptured AAA who were treated by open repair from July 2000 to June 2002. RESULTS: Mortality rate was 39% in the study group compared with 59% in the control group (P = .065). The duration of stay in the intensive care unit was significantly lower in the study group than in the control group (P = .01), although the total in-hospital stay was similar (17 days vs 14 days, P = .83). Within the study group, EVAR patients had a mortality rate of 24% compared with 47% in the open group (P = .14). CONCLUSION: Although the number of patients was small, offering EVAR to as many patients as possible with ruptured AAA has resulted in a 20% reduction in mortality, albeit statistically insignificant. However, it is in the unstable patients that EVAR will need to improve survival before it may be hailed to supersede the conventional approach.     

Morphologic changes and outcome following endovascular abdominal aortic aneurysm repair as a function of aneurysm size

HYPOTHESIS: Small infrarenal abdominal aortic aneurysms have a more favorable clinical and morphologic outcome compared with medium and large abdominal aortic aneurysms following endovascular aneurysm repair(EVAR). DESIGN: A prospective clinical series of 206 patients undergoing elective EVAR between 1996 and 2001. SETTING: A tertiary care academic health center. PATIENTS: Patients were grouped according to aneurysm size: small (<50 mm), medium (50-60 mm), and large (>60 mm). INTERVENTIONS: Primary EVAR and secondary procedures to secure fixation of the stent graft and surgical conversions. MAIN OUTCOME MEASURES: Aneurysm diameter, endoleaks, and long-term morphologic changes were analyzed postoperatively with 3-dimensional reconstructions of computed tomographic angiograms. RESULTS: Groups were similar in age, comorbidities, and follow-up (mean +/- SD, 32.1 +/- 11.8 months). There were 30 small aneurysms, 92 medium aneurysms, and 84 large aneurysms, with a mean size of 45.1 +/- 3.7 mm, 53.8 +/- 3.1 mm, and 66.1 +/- 6.8 mm, respectively (P<.01). There was no significant difference in proximal neck or iliac artery diameter among the 3 groups. The proximal aortic neck length (28.1 +/- 11.6 mm [small]; 23.9 +/- 11.3 mm [medium]; and 22.1 +/- 11.6 mm [large]; P<.05) was significantly shorter in large aneurysms. Furthermore, there was a significant increase (6% [small]; 15% [medium]; and 21% [large]; P<.05) in angulated necks in large aneurysms. Following treatment, aneurysm diameter remained stable in most patients (83% [small]; 82% [medium]; and 83% [large]), with a mean decrease of 2.0 +/- 6.5 mm, 2.1 +/- 6.1 mm, and 3.7 +/- 7.7 mm in each group, respectively (P =.45). There was no difference in the incidence of endoleaks, aneurysm contraction, or aneurysm expansion based on preoperative aneurysm diameter. Secondary procedures were performed in 5 (20%) of 25, 9 (5.2%) of 170, and 5 (36%) of 11 aneurysms that contracted, remained stable, or expanded, respectively, following EVAR (P<.05). CONCLUSIONS: There is a 15% increase in neck angulation and a 27% decrease in neck length in large compared with small infrarenal abdominal aortic aneurysms, with no difference in outcome. Aneurysms that are stable following EVAR have a significantly lower incidence of requiring secondary procedures.     

Branched grafting for aortoiliac aneurysms.

PURPOSE: To evaluate a novel approach to preserve pelvic perfusion during endovascular AAA repair in patients with common iliac aneurysms extending to the iliac bifurcation. MATERIALS AND METHODS: A multicenter prospective analysis of patients undergoing implantation of a branched endograft designed to perfuse the internal iliac artery was conducted. All patients enrolled were considered high risk for open surgical repair and presented with common iliac artery aneurysms greater than 20mm and anatomy amenable to implant the branched device. Preoperative high resolution spiral CT, and follow-up CT studies in addition to abdominal radiographs were obtained at discharge, 1, 6, 12, and 24 months. RESULTS: Between 2003 and 2006, 52 patients (53 internal iliacs) were implanted with an investigational device. Mean common iliac aneurysm maximal diameter was 38 mm. The branch graft was combined with a proximal standard bifurcated component (61%), a fenestrated or a visceral branch component (33%), an aortouni-iliac component (2%), and alone in 2 patients (4%, following prior aortobi-iliac repair). Technical success was achieved in 94% of patients. Within the first month, 6 (11%) internal iliac branches occluded. No occlusions were noted after 1 month. The mean follow-up was 14.2 months. Common iliac aneurysm shrinkage was noted in 42% and 81% of patients at 6 and 12 months. There were no rupture, aneurysm related deaths or conversions, but there were 7 deaths during follow-up. CONCLUSIONS: The placement of endovascular prostheses that maintain antegrade perfusion of one or both internal iliac arteries is feasible, and early results provide evidence for optimism with regard to safety and efficacy.     

Risk factors for endoleak and the evidence for stent-graft oversizing in patients undergoing endovascular aneurysm repair.

OBJECTIVES: the aim of this study was to assess the relationship between patient factors, the anatomy of the proximal aneurysm neck; the type of endovascular graft; and the consequences of graft/neck size mismatch and the occurrence of proximal endoleak. Design multicentre clinical study. MATERIALS: of a total of 2194 patients, 2146 underwent successful endovascular repair of infra-renal abdominal aortic aneurysms (AAA). METHODS: endoleaks were identified by radiological imaging immediately after completion of the procedure as per study protocols. Clinical and anatomical features of AAA in patients with endoleak were compared to patients without endoleak and data were analysed using the Chi-square test. A multivariate logistic regression model was constructed by selecting variables found to be significantly associated with complications in a univariate analysis. RESULTS: intra-operative endoleak was observed in 16.7% overall, and 3.3% were noted to have proximal endoleak. Aneurysm size larger than 60 mm (p =0.004), ex-smokers ( p =0.005) and age over 75 years ( p =0.01) were independently associated with endoleak of all types. Univariate and multivariate analysis revealed correlation between proximal endoleak and (i) diameter of the aneurysm neck-proximal (D2a), middle (D2b), distal (D2c), at all levels (p <0.005); (ii) proximal aortic neck length ( p =0.0001); (iii) aortic device diameter ( p =0.0024). No correlation was identified for angulation and form of the aortic neck. A model of the frequency of proximal endoleak, in relation to the ratio of the aortic device diameter to the distal aortic neck diameter, revealed that endoleak decreased when the aortic device diameter became oversized by more than 10% and confidence intervals remained tight for up to and over 20% oversize.     

Continuing expansion of internal iliac artery aneurysms after surgical exclusion of the inflow. A report of two cases

Two patients with continuing expansion of an internal iliac artery aneurysm following earlier repair of an aortoiliac aneurysm are described. At the primary operation, inflow to small internal iliac aneurysms had been interrupted by simple proximal ligation only. During follow-up, however, increasing diameter of the by CT-angiography completely thrombosed internal iliac aneurysms required re-operation. The observation of continuing growth of thrombosed internal iliac artery aneurysms following proximal ligation emphasises the danger of persistent collateral circulation and supports the concept of endotension in the absence of endoleak following endovascular AAA repair.     

Emergency endovascular repair for ruptured abdominal aneurysms--a feasibility study and report of 10 cases

BACKGROUND: Endovascular aneurysm repair (EVAR) has been proved to be effective and safe in the elective management of abdominal aortic aneurysms (AAAs). Initial reports concerning endovascular management of ruptured aneurysms have been promising. OBJECTIVE: To determine the outcome of endovascular repair of ruptured aneurysms in the local setting. Materials and methods. Patients who presented with ruptured AAAs were considered for endovascular repair if they were haemodynamically stable and had suitable aneurysm morphology for EVAR. RESULTS: Ten patients (9 males, 1 female) with a mean age of 74.9 years were treated. All aneurysms were successfully excluded using aorta uni-iliac stent grafts in 7 patients and bifurcated stent grafts in 2 patients. In 1 patient who had had a previous EVAR, a proximal extension device was used. Two patients died in the peri-operative period (30-day mortality of 20%) and 1 patient died after 2 months. Seven patients are still alive. No endo-leaks occurred in any of the survivors. CONCLUSION: Endovascular repair of ruptured AAAs is feasible with acceptable peri-operative mortality and short- to medium-term results.