Endovascular Aneurysm Repair Group Research Articles

Comparison of Costs of Endovascular Repair versus Open Surgical Repair for Abdominal Aortic Aneurysm in Korea

This study was designed to compare the hospital-related costs of elective abdominal aortic aneurysm (AAA) treatment and cost structure between endovascular aneurysm repair (EVAR) and open surgical repair (OSR) in Korean health care system. One hundred five primary elective AAA repairs (79 OSRs and 26 EVARs) performed in the Seoul National University Hospital from 2005 to 2009 were included. Patient characteristics were similar between two groups except for older age (P = 0.004) and more frequent history of malignancy (P = 0.031) in EVAR group. Thirty-day mortality rate was similar between two groups and there was no AAA-related mortality in both groups for 5 yr after repair. The total in-hospital costs for the index admission were significantly higher in EVAR patients (mean, KRW19,857,119) than OSR patients (mean KRW12,395,507) (P < 0.001). The reimbursement was also significantly higher in EVAR patients than OSR patients (mean, KRW14,071,081 vs KRW6,238,895, P < 0.001) while patients payments was comparable between two groups. EVAR patients showed higher follow-up cost up to 2 yr due to more frequent imaging studies and reinterventions for type II endoleaks (15.4%). In the perspective of cost-effectiveness, this study suggests that the determination of which method to be used in AAA treatment be more finely trimmed and be individualized.

Abdominal aortic aneurysm treatment: minimally invasive fast-track surgery and endovascular technique

In our department we started a program in order to offer a mini-invasive approach to all patients affected by abdominal aortic aneurysms (AAAs), trying to offer this option also to patients not eligible for endovascular aneurysm repair (EVAR) due to unfavorable anatomy, age under 65 years and aorto-iliac occlusive disease, considering nowadays EVAR is the gold-standard for the mini-invasive treatment of AAAs. The aim of this study was to compare endovascular versus fast-track surgical treatment in patients undergoing elective surgery for AAAs. We wanted to verify if it was possible to be totally mini-invasive in the treatment of AAAs. A total of 128 patients were chosen for the study. Ninety-four patients were enrolled in the OPEN group and 34 were enrolled in the EVAR group. This study demonstrates that minimally invasive treatment with the fast-track protocol may be a valid alternative to EVAR.

Invited commentary

Endovascular aneurysm repair (EVAR) has revolutionized the care of patients with abdominal aortic aneurysms. Several randomized studies (Dutch Randomised Endovascular Aneurysm Management Trial [DREAM], Open Versus Endovascular Repair Trial [OVER], EVAR-1) have demonstrated an initial perioperative survival benefit for EVAR patients compared with open repair. Long-term follow-up in these studies reveals that there continues to be a need for secondary interventions in the EVAR group at a steady annual rate. The most extreme secondary intervention occurs when an open conversion is required for a failure of endograft therapy. I would like to congratulate Dr Brinster and colleagues for sharing their experience with late open conversions for failed EVAR. As cited in their article, open conversion can be associated with a very high morbidity and mortality rate. They had no deaths in their series of 21 patients that required open conversion for a variety of reasons. Their mortality rate was zero despite 16 of the 21 patients requiring either a supraceliac or suprarenal aortic clamp site. And, they did not have any patients develop renal failure. The level of aortic cross-clamp that was required demonstrates the complexity of the explant operative procedure. An interesting finding of this series is the timing of the open conversion after initial EVAR therapy. The mean interval to conversion was 33.4 months. But, the range extended to 73 months after initial EVAR placement for the entire group. As endograft devices have improved over the years, the strict surveillance paradigms that were initially utilized in clinical trials and early clinical practice after device approval have been minimized in some centers. I have always been concerned about changing the surveillance schedule in light of the possibility of late failures. This article highlights the necessity for lifelong endograft surveillance. In fact, five patients required emergent open conversion. Two of these five patients were lost to follow-up after their respective 4- and 5-year CT scans that did not demonstrate any problems. This well-documented open conversion experience highlights the overall safety of the procedure in an experienced center despite an older patient population and a more complex operation due to the level of aortic cross-clamp. It also demonstrates that lifelong surveillance remains a critical part of EVAR. Late open conversion and explantation of abdominal aortic stent graftsJournal of Vascular SurgeryVol. 54Issue 1PreviewTo evaluate indications for, operative strategy during, and outcomes following late open surgical conversion following endovascular aneurysm repair (EVAR). Full-Text PDF Open Archive

Clinical Efficacy and Cost per Quality-Adjusted Life Years of Pararenal Endovascular Aortic Aneurysm Repair Compared With Open Surgical Repair

To gauge the efficacy of applying commercially-available endografts to pararenal endovascular abdominal aortic aneurysm (AAA) repair compared with open surgical repair (OSR). From 2001 to 2009, 1868 AAA patients were referred to our service for evaluation; of these, 118 patients had pararenal AAAs. Sixty-six patients (51 men; mean age 70.8±7.6 years) had OSR and 52 (44 men; mean age 74.3±7.2 years) underwent pararenal endovascular aneurysm repair (EVAR). The pararenal EVAR patients were older (74.3 versus 70.8 years, p = 0.014), with higher mean comorbidity severity scores (p = 0.0001). Mean aneurysm diameter was larger in the OSR patients (6.6 versus 5.9 cm, p = 0.01). Primary endpoints were aneurysm-related survival and cost per quality-adjusted life years (QALY). Secondary endpoints included 3-year freedom from major adverse clinical events, all-cause mortality, and secondary intervention. There was no perioperative mortality in the pararenal EVAR group versus 3 (4.5%) deaths among the OSR patients (p = 0.122). The 15% 30-day morbidity with pararenal EVAR was half that of OSR (p = 0.059). Mean follow-up was 28.8 ±21.6 months for pararenal EVAR and 35.7±23.2 months for OSR. There were no aneurysm ruptures in either group and no conversions to open repair in the pararenal EVAR group. Three-year aneurysm-related survival was significantly higher with pararenal EVAR (100%) versus OSR (92.4%, p = 0.045), but the freedom from any-cause death was lower with pararenal EVAR (57.1%) than OSR (84.8%, p = 0.195). Three-year freedom from secondary intervention (pararenal EVAR 83.4% versus OSR 95.5%, p = 0.301) and all-cause survival (pararenal EVAR 57.1% versus OSR 84.8%, p = 0.195) were similar. Over a 3-year period, pararenal EVAR costs (including follow-up and reintervention) averaged €20,375 per patient to give a QALY value of 0.90, while mean costs for OSR were €23,928 per patient (0.86 QALY). The incremental cost-effectiveness ratio for pararenal EVAR was €129,586 saved per QALY gained. Pararenal EVAR afforded patients longer quality-adjusted time without symptoms or toxicity and superior freedom from major adverse events up to 3 years. Although the relatively low 3-year survival rate reflected the greater comorbidity of the EVAR patients, pararenal EVAR was cost-effective.

Ruptured Thoracic Aneurysms

Recently published long-term outcomes of the UK Endovascular Abdominal Aortic Aneurysm Repair (EVAR) trial investigators and the Dutch Randomized Endovascular Aneurysm Repair group have continued to demonstrate the superiority of EVAR in the perioperative period, but they have failed to establish long-term sustainable durability compared to open repair because of increased graft-related complications and reinterventions.1,2 In 2005, thoracic endovascular aneurysm repair (TEVAR) was approved in the United States for the treatment of descending thoracic aortic aneurysms (DTAAs). This approval, based on the results of a phase II trial3 evaluating the GORE TAG endovascular prosthesis (W.L. Gore and Associates, Newark, Delaware), led to a nationwide explosion in the use of thoracic endovascular techniques for managing DTAAs.4 Physicians had already been performing EVAR for more than a decade. Whereas EVAR was initially used to repair abdominal aneurysms with a favorable anatomy, its use later expanded to include complex cases involving a short aneurysmal neck, a tortuous aorta, and (more recently) aneurysmal rupture. Although TEVAR has only a brief history, a similar trend is obvious: This approach is being used with reasonable success to treat dissections and even ruptured aneurysms5; in addition, various new debranching techniques are allowing TEVAR to be applied to portions of the aorta previously deemed unapproachable. Article see p 2718 Najibi and colleagues6 reported the results of the first study to compare TEVAR with open aortic repair. Their series comprised 18 patients, and the control group included a historic cohort of patients who had undergone open aortic repair during the previous 3 years. Short-term follow-up data showed that the endovascular group had significantly shorter operative times, shorter hospital and intensive-care–unit stays, and less operative blood loss. Subsequently, Bavaria and associates7 reported the results of a phase II multicenter trial that assessed GORE …

Hypothermia Is Associated With Increased Mortality in Patients Undergoing Repair of Ruptured Abdominal Aortic Aneurysm

To evaluate the impact of hypothermia on mortality in patients presenting with ruptured abdominal aortic aneurysms (rAAA). Between July 2007 and September 2009, 73 patients with ruptured AAAs presented to our Emergency Department (ED). Thirteen patients did not receive surgical treatment; of the 60 patients (46 men; mean age 76 years, range 63-90) who did, 35 had endovascular aneurysm repair (EVAR) and 25 open repair. Body temperatures, which were recorded upon arrival to the ED and operating room, during the procedure, and just prior to leaving the operating room, were analyzed for any association with mortality or hypotension. The primary outcome measure was the 30-day mortality rate. Six (17%) patients in the EVAR group and 10 (40%) patients in the open group died during the 30-day period. Temperature upon arrival to OR, lowest temperature recorded during the procedure, and temperature at the end of the procedure were higher among survivors (p<0.005), independent of the repair technique implemented. Patients in the EVAR group left the OR with a mean temperature of 35.5 degrees C versus 35.0 degrees C for patients in the open group (p = 0.12). Hypothermia is associated with increased mortality after repair of rAAA. Efforts to correct hypothermia are more frequently successful in patients undergoing EVAR. Increased communication with anesthesia providers, as well as aggressive measures to correct hypothermia, including active intravascular rewarming methods, should be considered to improve mortality in this gravely ill patient population.

Open vs endovascular repair of abdominal aortic aneurysm involving the iliac bifurcation

Aneurysmal involvement of the iliac bifurcation increases the level of difficulty during surgery for abdominal aortic aneurysm (AAA) repair, potentially increasing the risk of early postoperative complications. Three previous randomized trials comparing endovascular aneurysm repair (EVAR) and open repair (OR) for AAAs showed that EVAR is associated with a lower early mortality rate. However, whether these results are valid for AAA involving the iliac bifurcation (AAAIB) remains unclear. The aim of this study was to evaluate early and late results after OR and EVAR for patients with AAA involving the iliac bifurcation. Of 1116 patients treated for elective AAA repair between January 1998 and January 2008, 131 presented with AAAIB as detected by computed tomography (CT) scan. Sixty-eight patients were treated by EVAR and 63 by OR. Clinical and anatomic data, operative intervention, and outcomes were collected prospectively and analyzed retrospectively. The median duration of follow-up was 38 months for both groups. Patients in the EVAR group (72 +/- 10 years) were older than those in the OR group (64 +/- 8 years; P < .0001), but there were no differences in cardiac, renal, or pulmonary comorbidities between the two groups. Inhospital mortality rates were 2.9% vs 6.3% for EVAR and OR groups, respectively (P = .43). Systemic postoperative complications occurred in 7.4% vs 9.5% (P = .76) and postoperative colonic ischemia in 0% vs 6.3% (P = .051) of patients with EVAR and OR, respectively. Survival rates by Kaplan-Meier analysis were 91 +/- 7% for patients with EVAR and 90 +/- 8% for patients with OR at 2 years, and 61% +/- 15 for EVAR and 79% +/- 13 for OR at 5 years. All-cause reoperation rates were 25% with EVAR and 22% with OR (P = .83). Patients with EVAR were more likely to develop buttock claudication (33.3% vs 3.6%; P < .0001), whereas patients with OR were more prone to develop abdominal wall complications (19.6% vs 0%; P < .001). In this series, the postoperative mortality and systemic complication rates after either EVAR or OR for AAAIB were not statistically different. In the OR group, there were more abdominal wall complications and a trend toward a higher rate of colonic ischemia. In the EVAR group, buttock claudication was more frequent.

Five-year Experience with Endovascular Aneurysm Repair without Fenestration for Pararenal Aortic Aneurysms: Clinical Efficacy, Reintervention Rates, and Cost-effectiveness Compared with Open Repair in High Deliberate-practice Volume Centers

Although endovascular aneurysm repair (EVAR) affords more favorable perioperative and long-term survival than open surgical repair (OSR), approximately 50% of abdominal aortic aneurysms (AAAs) are anatomically unsuitable for EVAR using commercially available devices. Our goal was to gauge the extended use of devices for pararenal aneurysm compared with OSR. Primary end points were aneurysm-related survival, secondary intervention, and cost per quality-adjusted life-year (QALY). From 2002 to 2009, 1769 patients with AAA were seen at our unit, of which 92 had interventions for pararenal AAAs that were reported by radiology as unsuitable for EVAR: 54 had OSR, 38 had EVAR. Unsuitability for EVAR included no normal aortic neck, neck angle >90°, and neck thrombus >4 mm. The EVAR group was significantly older (74.5 vs 71.1 years, P = .034), with a significantly higher mean Society of Vascular Surgery comorbidity severity scores (P < .0001) and Kertai Customized Probability Indices (P = .05). Most endografts (83%) were 36-mm diameter, and the mean proximal diameter was 32 mm. All OSRs were done with a diagonally placed proximal clamp, preserving flow to the highest renal artery. The renal arteries were reimplanted in four cases and the internal mesenteric artery in one. The 5-year aneurysm-related survival rates were higher with EVAR (100%) compared with OSR (94.4%, P > .05), although this did not reach statistical significance. The 5-year freedom from secondary intervention was similar between EVAR (94.1%, [95% confidence interval [CI], 80.1%-98.8%]) and OSR (100%, P > .05). The 5-year all-cause survival was significantly reduced in the EVAR group (50.4%, 95% CI, 34%-66%.) vs OSR (80.4%, [95% CI, 66.9%-89.5%; P = .0279; h, 0.34 [95% CI, 0.12-0.94]). However, none of the deaths in the EVAR group were aneurysm-related. The 30-day morbidity (P < .0001), length of hospital stay (P < .0001), 5-year quality-adjusted time spent without symptoms of disease and toxicity of treatment (P < .01), and cost per QALY (P < .01) were all significantly reduced with EVAR compared with OSR. Endografts can be effectively used to treat difficult pararenal AAAs, with enhanced long-term aneurysm-related survival, cost-effectiveness, and quality of life, and with significantly reduced perioperative morbidity, mortality, and waiting time from diagnosis to treatment.

Does EVAR Alter the Rate of Cardiovascular Events in Patients with Abdominal Aortic Aneurysm Considered Unfit for Open Repair? Results from the Randomised EVAR Trial 2

Objectives: To investigate whether EndoVascular Aneurysm Repair (EVAR) influences the rate of cardiovascular events (fatal or non-fatal myocardial infarction or stroke) in patients with abdominal aortic aneurysm (AAA) considered unfit for open repair. Design: Randomised controlled trial. Materials: Between 1999 and 2004, 404 patients with large AAA considered unfit for open repair were randomised to EVAR or no surgical intervention across 33 UK hospitals and followed until July 2009. Methods: The Customised Probability Index was used to determine fitness for each patient and Cox regression was used to compare time to first cardiovascular event between randomised groups and levels of fitness. Results: During an average of 2.8 years of follow-up, 67 first cardiovascular events occurred with a non-significantly higher event rate in the EVAR group compared to the no intervention group (6.6 versus 5.1 events per 100 person years); adjusted hazard ratio 1.42 [95% CI 0.87–2.34], p = 0.156. There was no evidence to suggest that the hazard ratio between randomised groups changed with level of fitness (p = 0.378). Conclusions: Cardiovascular event rates were high in these unfit patients and medical therapy was sub-optimal. Events rates were slightly higher in the EVAR group but this was not statistically significant.

Five-year results for the Talent enhanced Low Profile System abdominal stent graft pivotal trial including early and long-term safety and efficacy

The pivotal trial of the Talent enhanced Low Profile System (eLPS; Medtronic Vascular, Santa Rosa, Calif) stent graft evaluated short and long-term safety and efficacy of endovascular aneurysm repair (EVAR). These data and a confirmatory group assessing the performance of the CoilTrac delivery system supported the United States premarket approval application for the device. The pivotal trial was a prospective, nonrandomized study conducted at 13 sites from February 2002 to April 2003. The study group (n = 166) underwent EVAR using the Talent eLPS stent graft. The control group (n = 243) underwent open surgical AAA repair. Data for this group were obtained from the Society for Vascular Surgery Endovascular AAA Surgical Controls project. Outcomes were compared at 30 days and 12 months. Additional 5-year follow-up was obtained for the eLPS group. A single-center cohort of 137 patients was the confirmatory group for the assessment of the clinical performance of the CoilTrac delivery system, with analysis of outcomes <or=30 days from the procedure. AAA anatomy with neck length as short as 3 mm and maximum neck diameter of 32 mm were included in the eLPS group. EVAR was superior to open repair for periprocedural outcomes, including mean procedure duration (167.3 vs 196.4 minutes, P < .001), blood transfusion (18.2% vs 56.8%, P < .001), median intensive care unit stay (19.3 vs 74.3 hours, P < .001), and mean hospital stay (3.6 vs 8.2 days, P < .001). Freedom from major adverse events was 89.2% for EVAR at 30 days vs 44.0% (P < .001) and 81.3% vs 42.4% at 1 year (P < .001). Freedom from all-cause mortality and aneurysm-related mortality (ARM) was 93.7% and 98.2% for EVAR vs 92.4% and 96.7% for the controls. Through 5 years for the EVAR group, rates of freedom from all-cause mortality, ARM, aneurysm rupture, and conversion to surgery were 69.8%, 96.5%, 98.2%, and 99.1%, respectively, with one conversion to surgery, 25 secondary reinterventions, and five site-reported instances of stent graft migration. The technical success rate for the CoilTrac confirmatory group was 100%, with no aneurysm rupture or conversion to open repair at 30 days. The 30-day all-cause mortality rate was 1.5% (2 of 137). In a population with challenging anatomic characteristics, EVAR with the Talent eLPS and use of the CoilTrac delivery system compared favorably with open repair through 1 year. Sustained protection from ARM, with minimal reinterventions, was attained through 5 years.

Does EVAR Alter the Rate of Cardiovascular Events in Patients with Abdominal Aortic Aneurysm Considered Unfit for Open Repair? Results from the Randomised EVAR Trial 2

Objectives To investigate whether EndoVascular Aneurysm Repair (EVAR) influences the rate of cardiovascular events (fatal or non-fatal myocardial infarction or stroke) in patients with abdominal aortic aneurysm (AAA) considered unfit for open repair. Design Randomised controlled trial. Materials Between 1999 and 2004, 404 patients with large AAA considered unfit for open repair were randomised to EVAR or no surgical intervention across 33 UK hospitals and followed until July 2009. Methods The Customised Probability Index was used to determine fitness for each patient and Cox regression was used to compare time to first cardiovascular event between randomised groups and levels of fitness. Results During an average of 2.8 years of follow-up, 67 first cardiovascular events occurred with a non-significantly higher event rate in the EVAR group compared to the no intervention group (6.6 versus 5.1 events per 100 person years); adjusted hazard ratio 1.42 [95% CI 0.87–2.34], p = 0.156. There was no evidence to suggest that the hazard ratio between randomised groups changed with level of fitness ( p = 0.378). Conclusions Cardiovascular event rates were high in these unfit patients and medical therapy was sub-optimal. Events rates were slightly higher in the EVAR group but this was not statistically significant.

Management of ruptured abdominal aortic aneurysm in the endovascular era

Our institution treats about 30 patients per year with ruptured abdominal aortic aneurysms (rAAA). Between 2002 and 2007, our 30-day mortality averaged 58%. In July 2007, we implemented an algorithm to promote endovascular aneurysm repair (EVAR) when feasible. This report describes the outcome with this approach. Data on patients presenting with rAAA between July 1, 2002, and June 30, 2007, were reviewed and used for comparison to prospectively collected data. Data on patients presenting between July 1, 2007, and April 30, 2009, were collected on all patients after implementation of a structured protocol. The primary outcome measure was 30-day mortality. Data were analyzed using logistic regression. Kaplan-Meier survival curves and a log-rank test were performed to compare survival times for three groups (pre-protocol, post-protocol with open surgery, and post-protocol with EVAR). During the study period, 187 patients with rAAA presented to our institution. Before implementation of the algorithm, 131 patients with rAAA presented and 128 were treated. The 30-day mortality rate was 57.8%. After implementation of the protocol, 56 patients with rAAA were managed. Twenty-seven patients (48%) underwent successful EVAR, and 24 patients (43%) underwent open repair. Five patients (9%) underwent comfort care only. In the post-protocol period, 5 patients in the EVAR group (18.5%) and 13 patients in the open group (54.2%) died during the follow-up period for an overall 30-day mortality rate of 35.3% (P = .008 vs 57.8% pre-protocol). After implementation of a structured protocol for managing rAAA, there was a relative risk reduction in 30-day mortality of 35% compared to the time before implementation of the protocol (95% confidence interval [CI], 14%-51%) corresponding to an absolute risk reduction of 22.5% (95% CI, 6.8%-38.2%) and an odds ratio of 0.40 (95% CI, 0.20-0.78; P = .007). After adjusting for key factors predicting mortality, the odds ratio is 0.25 (95% CI, 0.10-0.57; P = .001). Use of an algorithm favoring endovascular repair resulted in a highly significant reduction in rAAA mortality in our urban hospital. Thirty-day mortality for open repair was no different between pre- and post-protocol eras. With modern techniques of resuscitation and surgical management, a majority of patients presenting with rAAA can survive.

A Systematic Review of Open Versus Endovascular Repair of Inflammatory Abdominal Aortic Aneurysms

Inflammatory abdominal aortic aneurysms (IAAAs) have traditionally been treated by open surgical repair (OSR). Over the last decade, endovascular aneurysm repair (EVAR) has been increasingly employed. The optimal treatment option for IAAA remains unclear. This article aims to evaluate and compare outcomes of OSR and EVAR in IAAA repair. All publications in the English language relating to IAAA were sought electronically using OVID and MEDLINE (1972-2008). Studies identifying 30-day mortality were considered. Periaortic inflammation (PAI), hydronephrosis and 1-year mortality were obtained from studies with at least 1-year computed tomography (CT) follow-up. Outcomes of OSR and EVAR were compared and analysed for statistical significance using Fisher's exact test. The results were obtained from 35 studies comprising 999 patients and 21 studies with 121 patients who underwent OSR and EVAR, respectively. One-year CT follow-up was available for 124 and 52 patients from the two groups, respectively. Thirty-day mortality after OSR was 6% (95% confidence interval (CI); 6-13) and 2% (95% CI; 0-7) after EVAR (p=0.1). At 1 year, PAI regressed in 73% (95% CI; 64-80) in the OSR group compared to 65% (95% CI; 49-77) of the EVAR group (p=0.7). Conversely, inflammation progressed in 1% and 4%, respectively (p=0.1). Forty-five patients undergoing OSR and 29 EVAR were found to have preoperative hydronephrosis. This regressed postoperatively in 69% (95% CI; 53.3-81.8) and 38% (95% CI; 20.6-57.7), respectively (p=0.01). Hydronephrosis progressed in 9% of patients after OSR and in 21% after EVAR (p=0.1). New-onset hydronephrosis developed in 6% undergoing OSR compared to 2% with EVAR (p=0.2). One-year all-cause mortality after OSR was 14% (95% CI; 6-18) compared to 2% (95% CI; 0-13) after EVAR (p=0.02). Either OSR or EVAR may be considered based on patient suitability. EVAR is associated with lower 1-year mortality compared to OSR. However, OSR may be preferred in those patients who have hydronephrosis and are deemed low risk.

The AAA With a Challenging Neck: Outcome of Open Versus Endovascular Repair With Standard and Fenestrated Stent-Grafts

To compare the outcome of endovascular aneurysm repair (EVAR) versus conventional open repair (OR) in patients with a short, angulated or otherwise challenging proximal neck. The definition of a challenging proximal neck was based on diameter (>or=28 mm), length (<or=15 mm), angulation (>or=60 degrees ), shape (reverse tapered or bulging), and thrombus lining (>50%). Between January 2005 and December 2007, 187 consecutive patients (159 men; mean age 73 years, range 48-92) operated for asymptomatic abdominal aortic aneurysm (AAA) were identified as having challenging proximal neck morphology. Of these, 61 patients were treated with OR at center I (group A), 71 with standard EVAR (group B; 45 center I, 29 center II) and 52 with fenestrated EVAR (group C) at center II. Clinical examination and computed tomography were performed at 1 month and yearly thereafter. There was no statistically significant difference between groups A, B, and C regarding primary technical success rate, 30-day mortality, or late AAA-related mortality. The mean length of follow-up was 19.5 months (range 0-40). Freedom from reintervention at 3 years was 91.8%, 79.7%, and 82.7% for groups A, B, and C, respectively (p = 0.042). The only statistically significant difference between standard and fenestrated EVAR was a higher incidence of late sac expansion [9 (12.2%) versus 1 (1.9%), p = 0.036] in the standard stent-graft group. Reinterventions were more frequent after EVAR (p = NS), but open reinterventions were more common after OR. Reinterventions after EVAR were related to the presence of an angulated (p = 0.039) or short neck (p = 0.024). The results of EVAR and OR were similar for AAAs with a challenging proximal neck. Endovascular reinterventions were more frequent after EVAR, particularly in patients with an angulated or short neck. Open reinterventions were more common after OR. More patients and long-term data are needed to confirm these findings.

Improving Results of Elective Abdominal Aortic Aneurysm Repair at a Low-Volume Hospital by Risk-Adjusted Selection of Treatment in the Endovascular Era

Several studies have observed both higher mortality rates and lower utilization of endovascular aneurysm repair (EVAR) at low-volume centers. This article presents the results of elective abdominal aortic aneurysm (AAA) repair at a low-volume center in the endovascular era and investigates whether postprocedural mortality can be improved by extension of EVAR application also in this setting. This is an 11.6-year retrospective cohort study of 132 patients undergoing elective surgical or endovascular AAA repair at a tertiary care academic hospital between 1997 and July 2008, i.e., a median volume of 12 cases per year. The study was divided into two periods of time according to the respective indications and contraindications for EVAR, which substantially changed in 2005. During period 1, only aneurysms with necks > or =20 mm long and not involving the iliac arteries were treated endoluminally. Beginning in 2005, indication for EVAR was expanded to aortoiliac aneurysms with a minimum neck length of 15 mm. Preoperative risk was assessed by the SVS/AAVS comorbidity score. During the first period (1997-2004) 18.4% (16/87) of all patients received EVAR. By extending anatomical confines and indications for EVAR in 2005, the utilization rate of EVAR increased to 40.0% (18/45) during the second period (2005-July 2008; p = 0.007). Prevalence of preoperative risk factors did not change during the two observation periods. In contrast to period 1, high-risk patients were preferentially treated endoluminally during the second period, resulting in a significantly higher median SVS/AAVS score in the EVAR group (p < 0.001). A significant decrease in median length of stay at the intensive/intermediate care unit (5 vs. 2 days; p = 0.006) and length of in-hospital stay (20 vs. 12.5 days; p < 0.001) was observed during period 2. Overall perioperative mortality was reduced from 6.9% during the first period to 2.2% during the second period (p = 0.256). EVAR mortality was 0%, mortality after open repair was reduced from 8.5% to 3.7% (p = 0.414). In conclusion, by risk-adjusted selection of treatment and frequent application of EVAR, it is possible to improve perioperative outcome of elective AAA repair at a low-volume hospital. Mortality figures are similar to those of recent trials at high-volume centers, as reported in the literature.

Outcomes of endovascular abdominal aortic aneurysm repair compared with open surgical repair in high-risk patients: Results from the Swedish Vascular Registry

The management of infrarenal aortic aneurysms in high-risk patients remains a challenge. Endovascular aneurysm repair (EVAR) is associated with superior short-term mortality rates but unclear long-term results and has not been shown to improve survival in patients unfit for open repair (OR). The aim of this population-based study was to evaluate the outcome after elective EVAR compared with OR in a high-risk patient cohort. Prospectively collected data from January 2000 to December 2006 were retrieved from the Swedish Vascular Registry. The high-risk cohort was defined as age >or=60 years, American Anesthesiologists Association (ASA) class 3 or 4, and at least one cardiac, pulmonary, or renal comorbidity. These criteria were met by 217 of 1000 EVAR patients and 483 of 2831 OR patients. Primary end points were 30-day and 1-year all-cause mortality. Kaplan-Meier curves for survival and multivariate Cox regression analyses were performed. The crude 30-day and 1-year all-cause mortality rates for EVAR vs OR for the whole treatment group (n = 3831) were 1.8% vs 2.8% and 8.0% vs 7.2%, respectively. In the high-risk cohort (n = 700), EVAR patients were approximately 2 years older and renal insufficiency and diabetes mellitus were more common, and smoking was more prevalent in the OR group. About two-thirds of EVAR procedures were performed at university hospitals and one-half of OR procedures were performed at county hospitals. In the high-risk cohort, there was no difference in mortality at 30-days (EVAR, 4.6% vs OR, 3.3%), but OR had lower 1-year mortality (8.5% vs 15.9%; P = .003). More bleeding complications occurred in the EVAR group, but more pulmonary complications occurred in the OR group; however, there was no difference in cardiac, cerebrovascular, or renal complications. The mean follow-up was 3.4 years. EVAR was associated with increased mortality risk after adjusting for age, ASA class, and comorbidities (hazard ratio, 1.50; 95% confidence interval, 1.07-2.12; P = .02). Kaplan-Meier survival analysis showed a lower mortality rate for patients undergoing OR, which remained during follow-up (P = .001). Elective OR of aortic aneurysms seems to have a better outcome compared with EVAR in this specific, population-based, high-risk patient cohort after adjusting for covariates. We cannot confirm the benefit of EVAR from previous registry studies with a similar high-risk definition. In clinical practice, OR may be at least as good as EVAR in high-risk patients fit for surgery.

Comparison of the effects of open and endovascular aortic aneurysm repair on long-term renal function using chronic kidney disease staging based on glomerular filtration rate

It has been suggested that endovascular aneurysm repair (EVAR) in concert with serial contrast-enhanced computed tomography (CT) surveillance adversely impacts renal function. Our primary objectives were to assess serial renal function in patients undergoing EVAR and open repair (OR) and to evaluate the relative effects of method of repair on renal function. A thorough retrospective chart review was performed on 223 consecutive patients (103 EVAR, 120 OR) who underwent abdominal aortic aneurysm (AAA) repair. Demographics, pertinent risk factors, CT scan number, morbidity, and mortality were recorded in a database. Baseline, 30- and 90-day, and most recent glomerular filtration rate (GFR) were calculated. Mean GFR changes and renal function decline (using Chronic Kidney Disease [CKD] staging and Kaplan-Meier plot) were determined. EVAR and OR patients were compared. CKD prevalence (>or=stage 3, National Kidney Foundation) was determined before repair and in longitudinal follow-up. Observed-expected (OE) ratios for CKD were calculated for EVAR and OR patients by comparing observed CKD prevalence with the expected, age-adjusted prevalence. The only baseline difference between EVAR and OR cohorts was female gender (4% vs 12%, P = .029). Thirty-day GFR was significantly reduced in OR patients (P = .047), but it recovered and there were no differences in mean GFR at a mean follow-up of 23.2 months. However, 18% to 39% of patients in the EVAR and OR groups developed significant renal function decline over time depending on its definition. OE ratios for CKD prevalence were greater in AAA patients at baseline (OE 1.28-3.23, depending upon age group). During follow-up, the prevalence and severity of CKD increased regardless of method of repair (OE 1.8-9.0). Deterioration of renal function was independently associated with age >70 years in all patients (RR 2.92) and performance of EVAR compared with OR (RR 3.5) during long-term follow-up. Compared with EVAR, OR was associated with a significant but transient fall in GFR at 30 days. Renal function decline after AAA repair was common, regardless of method, especially in patients >70 years of age. However, the renal function decline was significantly greater by Kaplan-Meier analysis in EVAR than OR patients during long-term follow-up. More aggressive strategies to monitor and preserve renal function after AAA repair are warranted.

Matched-pair Analysis of Endovascular versus Open Surgical Repair of Abdominal Aortic Aneurysms in Young Patients at Low Risk

To compare clinical outcomes of endovascular and open aortic repair of abdominal aortic aneurysms (AAAs) in young patients at low risk. It was hypothesized that endovascular aneurysm repair (EVAR) compares favorably with open aneurysm repair (OAR) in these patients. Twenty-five patients aged 65 years or younger with a low perioperative surgical risk profile underwent EVAR at a single institution between April 1994 and May 2007 (23 men; mean age, 62 years+/-2.8). A sex- and risk-matched control group of 25 consecutive patients aged 65 years or younger who underwent OAR was used as a control group (23 men; mean age, 59 years+/-3.9). Patient outcomes and complications were classified according to Society of Vascular Surgery/International Society for Cardiovascular Surgery reporting standards. Mean follow-up times were 7.1 years+/-3.2 after EVAR and 5.9 years+/-1.8 after OAR (P=.1020). Total complication rates were 20% after EVAR and 52% after OAR (P=.0378), and all complications were mild or moderate. Mean intensive care unit times were 0.2 days+/-0.4 after EVAR and 1.1 days+/-0.4 after OAR (P<.0001) and mean lengths of hospital stay were 2.3 days+/-1.0 after EVAR and 5.0 days+/-2.1 after OAR (P<.0001). Cumulative rates of long-term patient survival did not differ between EVAR and OAR (P=.144). No AAA-related deaths or aortoiliac ruptures occurred during follow-up for EVAR and OAR. In addition, no surgical conversions were necessary in EVAR recipients. Cumulative rates of freedom from secondary procedures were not significantly different between the EVAR and OAR groups (P=.418). Within a multivariable Cox proportional-hazards analysis adjusted for patient age, maximum AAA diameter, and cardiac risk score, all-cause mortality rates (odds ratio [OR], 0.125; 95% CI, 0.010-1.493; P=.100) and need for secondary procedures (OR, 5.014; 95% CI, 0.325-77.410; P=.537) were not different between EVAR and OAR. Results from this observational study indicate that EVAR offers a favorable alternative to OAR in young patients at low risk.

Response of plasma matrix metalloproteinases and tissue inhibitor of metalloproteinases to stent-graft surgery for descending thoracic aortic aneurysms

The role of matrix metalloproteinases and their tissue endogenous inhibitors has been documented in abdominal aortic aneurysms, but few articles have investigated their role after thoracic aortic aneurysm treatment. Our report investigates matrix metalloproteinases and tissue endogenous inhibitor-1 plasmatic changes in patients who have undergone endovascular aneurysm repair for descending thoracic aortic aneurysms and assesses their clinical significance. Thirty-two patients with thoracic aortic aneurysms who underwent endovascular aneurysm repair were compared with 25 healthy volunteers. Plasma matrix metalloproteinase-3/matrix metalloproteinase-9 and tissue endogenous inhibitor-1 values were determined by an enzyme-linked immunosorbent assay method at a predetermined time interval. The preoperative levels of matrix metalloproteinases in the endovascular aneurysm repair group were 3-fold and 2-fold higher than those in the control group (P < .001 and .02, respectively). Matrix metalloproteinase values normalized after endovascular aneurysm repair, whereas patients experiencing endoleaks had higher matrix metalloproteinase values and matrix metalloproteinase-9/tissue endogenous inhibitor-1 ratio compared with the control group (P = .003, < .001, and = .02, respectively, at 1-month follow-up). These values normalized with the resolution of the endoleak. Plasma matrix metalloproteinase values are increased in patients with thoracic aortic aneurysms, along with reduced tissue endogenous inhibitor-1 expression. Successful endovascular aneurysm repair results in values normalization, whereas high levels persist in patients with endoleaks. The enzyme-linked immunosorbent assay test is a simple and reliable technique that is useful to assess the efficacy of endovascular aneurysm repair and to detect endoleaks.

Hypotensive Hemostatis (Permissive Hypotension) for Ruptured Abdominal Aortic Aneurysm: Are We Really in Control?

The purpose of this study was to investigate whether a protocol for permissive hypotension was feasible for patients admitted with a ruptured abdominal aortic aneurysm (RAAA). It was aimed to limit prehospital intravenous fluid administration to 500 mL and to maintain systolic blood pressure at a range of 50 to 100 mm Hg following admission, using nitrates when indicated. The diagnosis of RAAA was confirmed with sonography, and all patients with uncontrolled hypovolemic shock immediately underwent open aneurysm repair (OAR). In all other cases, computed tomographic (CT) angiography was performed to determine the eligibility for endovascular aneurysm repair (EVAR). From January 1, 2004, to December 31, 2006, 95 patients with a suspected RAAA were admitted. In 77 patients, the diagnosis of RAAA was confirmed. Twenty-eight cases (36%) underwent OAR for uncontrolled hemodynamic instability. Following CT-angiographic evaluation, 25 of the remaining 49 cases were considered unsuitable for EVAR and subsequently underwent OAR. In 24 of 77 cases (31%), the RAAA was treated with EVAR. Preoperative systolic blood pressure recordings in EVAR patients showed median values (+/- SD) of 98 (+/- 34.7) mm Hg in the emergency department and 114 (+/- 26.2) mm Hg in the operating theater. The desired systolic blood pressure range of 50 to 100 mm Hg was reached in 11 of 24 cases (46%). In 13 of 24 cases (54%), a systolic blood pressure higher than 100 mm Hg was recorded for a period longer than 60 minutes. The 30-day mortality was 32 of 77 (42%), with 6 of 24 (25%) in the EVAR group and 26 of 53 (49%) in the OAR group. This is the first published series of RAAA in which a protocol of permissive hypotension has been adopted. The concept appeared to be feasible in the majority of cases. Protocol violations were sparse (n = 5). Uncontrolled hypotension occurred in 36% (28 of 77) of all patients, and the desired systolic blood pressure range was achieved in 46% (11 of 24) of the EVAR patients.