***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: OBJECTIVE To assess the efficacy of endovascular aneurysm repair ( EVAR ) against st and ard alternative management in patients with large abdominal aortic aneurysm ( AAA ) . DESIGN Two national , multicentre r and omised trials - EVAR trials 1 and 2 . SETTING Patients were recruited from 38 out of 41 eligible UK hospitals . PARTICIPANTS Men and women aged at least 60 years , with an AAA measuring at least 5.5 cm on a computerised tomography scan that was regarded as anatomically suitable for EVAR , were assessed for fitness for open repair . Patients considered fit were r and omised to EVAR or open repair in EVAR trial 1 and patients considered unfit were r and omised to EVAR or no intervention in EVAR trial 2 . INTERVENTIONS EVAR , open repair or no intervention . MAIN OUTCOME MEASURES The primary outcome was mortality ( operative , all-cause and AAA related ) . Patients were flagged at the UK Office for National Statistics with central ly coded death certificates assessed by an Endpoints Committee . Power calculations based upon mortality indicated that 900 and 280 patients were required for EVAR trials 1 and 2 , respectively . Secondary outcomes were graft-related complications and re interventions , adverse events , renal function , health-related quality of life and costs . Cost-effectiveness analyses were performed for both trials . RESULTS Recruitment occurred between 1 September 1999 and 31 August 2004 , with targets exceeded in both trials : 1252 r and omised into EVAR trial 1 ( 626 to EVAR ) and 404 r and omised into EVAR trial 2 ( 197 to EVAR ) . Follow-up closed in December 2009 with very little loss to follow-up ( 1 % ) . In EVAR trial 1 , 30-day operative mortalities were 1.8 % and 4.3 % in the EVAR and open-repair groups , respectively : adjusted odds ratio 0.39 [ 95 % confidence interval ( CI ) 0.18 to 0.87 ] , p = 0.02 . During a total of 6904 person-years of follow-up , 524 deaths occurred ( 76 AAA related ) . Overall , there was no significant difference between the groups in terms of all-cause mortality : adjusted hazard ratio ( HR ) 1.03 ( 95 % CI 0.86 to 1.23 ) , p = 0.72 . The EVAR group did demonstrate an early advantage in terms of AAA-related mortality , which was sustained for the first few years , but lost by the end of the study , primarily due to fatal endograft ruptures : adjusted HR 0.92 ( 95 % CI 0.57 to 1.49 ) , p = 0.73 . The EVAR procedure was more expensive than open repair ( mean difference £ 1177 ) and not found to be cost-effective , but the model was sensitive to alternative assumptions . In EVAR trial 2 , during a total of 1413 person-years of follow-up , a total of 305 deaths occurred ( 78 AAA related ) . The 30-day operative mortality was 7.3 % in the EVAR group . However , this group later demonstrated a significant advantage in terms of AAA-related mortality , but this became apparent only after 4 years : overall adjusted HR 0.53 ( 95 % CI 0.32 to 0.89 ) , p = 0.02 . Sadly , this advantage did not result in any benefit in terms of all-cause mortality : adjusted HR 0.99 ( 95 % CI 0.78 to 1.27 ) , p = 0.97 . Overall , EVAR was more expensive than no intervention ( mean difference £ 10,222 ) and not found to be cost-effective . CONCLUSIONS EVAR offers a clear operative mortality benefit over open repair in patients fit for both procedures , but this early benefit is not translated into a long-term survival advantage . Among patients unfit for open repair  , EVAR is associated with a significant long-term reduction in AAA-related mortality but this does not appear to influence all-cause mortality . TRIAL REGISTRATION Current Controlled Trials IS RCT N 55703451 . FUNDING This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment ; Vol . 16 , No. 9 . See the HTA programme website for further project information The modern era of aortic aneurysm repair started in AAA 4.0 - 5.5 cm in diameter . 5 The U.K Small AnEurope . The first successful resection of an abdominal eurysm Trial Participants were 126 vascular surgeons aortic aneurysm , with homograft replacement , was from 93 hospitals who collaborated in a r and omised performed in Paris on 25th March , 1951 , by Dubost trial to collect the evidence to answer the question : and colleagues , t Homografts were rapidly replaced does early elective surgery or ultrasound surveillance by prosthetic grafts of man-made fibres . Since then provide the better management for patmnts with small prostheses have been developed and st and ardised , AAA ? the operative techniques refined and anaesthesia has In the 4-year period between Autumn 1991 and improved . The number of aneurysms repaired electAutumn 1995 , 1090 patients , aged 60 - 76 years , were lvely each year continues to rise , with procedures m r and omised to a treatment policy of either early electEngl and and Wales having almost doubled recently , i ve surgery ( n=563 ) or a period of ultrasound surfrom 1405 to 2378 in the five years from 1990 - 1995 . 2 velllance ( n = 527 ) .  Ultrasound surveillance  was Few have stopped to consider to what extent the continued at regular intervals untd the anaurysm diapatmnt benefits from elective surgical repair of an meter exceeded 5.5 cm , the aneurysm became tender , abdominal aortic aneurysm . Since the start of ultraor the aneurysm grew by > 1 cm in a year . The trial sound screening programmes m the 1980s , more and protocol , together with details of how the trial was more asymptomatic abdominal aortic aneurysms executed , have been published previously in this ( AAAs ) are being detected . 3 Most of these screenjournal . 5 detected AAAs are small , < 5.5 cm in diameter . Should The end points of the UK Small Aneurysm Trial such aneurysms be repaired electlvely ? The first evlwere : all cause mortahty ; aneurysm related mortality ; dence to answer this question comes from Europe . quality of life ; costs and cost-effectiveness . The U K. Small Aneurysm Trial reported at the Annual An independent Data Monitoring and Ethics CornMeeting of the Vascular Surgical Society of Great Britmlttee review ed the progress of the trial after each ain and Irel and in November 1998 . 4 The evidence , successive 70 deaths and was empowered to stop the outlined below , indicates that elective open surgical trial at any point , should either one treatment arm repair of an asymptomatic AAA of < 5.5 cm in diameter be clearly superior or the 30-day operative mortahty should not be recommended , exceed 5 % ( allowing for appropriate confidence inThe U.K. Small Aneurysm Trial was established m tervals ) . The trial participants and Trial Steering Com1991 because many vascular surgeons in Britain were mittee were blind to all results until after the trial uncertain whether elective surgical aneurysm repair closed on 30th June , ] 998 . At this time the mean patient should be offered to patients with small asymptomatic follow-up was 4.6 years and 309 deaths had been recorded . At r and omisatlon , the baseline characteristics of the 563 patients r and omised to early elective surgery and Please address all correspondence to l T Powell , Imperial College School of Medicine , Charmg Cross Hospital , Fulham Palace Road , the 527 patients r and omised to ultrasound surveillance London W6 8RF , U K were very similar . The mean age of the surgery INTRODUCTION EVAR has the potential to improve outcome after ruptured abdominal aortic aneurysm ( AAA ) . Published series have been based upon selected population s. METHODS An interim analysis of a single centre prospect i ve r and omised controlled trial comparing endovascular aneurysm repair ( EVAR ) with open aneurysm repair ( OAR ) in patients with ruptured AAA was performed . Patients who had a ruptured AAA and who were considered fit for open repair were r and omised to EVAR or OAR  after consent had been obtained . Those in the EVAR group had pre-operative spiral computed tomographic angiography ( CTA ) . The primary endpoint was operative ( 30-day ) mortality and secondary endpoints were moderate or severe operative complications , hospital stay and time between diagnosis and operation . A power study calculation required 100 patients to be recruited . RESULTS Between September 2002 and December 2004 , 103 patients were admitted with suspected ruptured AAA . Only 32 patients were recruited to the study . Of these , four patients died before receiving surgical treatment . On an intention to treat basis the 30-day mortality rate was 53 % in the EVAR group and 53 % in the OAR group . Moderate or severe operative complications occurred in 77 % in the EVAR group and in 80 % in the OAR group . Median total hospital stay in the EVAR group was 10 days ( inter-quartile range 6 - 28 ) and 12 days ( 4 - 52 ) in the OAR group . Median time between diagnosis and operation was 75 minutes ( 64 - 126 ) in the EVAR group and 100 minutes ( 48 - 138 ) in the OAR group . CONCLUSIONS Despite the relative high operative mortality in the EVAR group , these preliminary results show that it is possible to recruit patients to a r and omised trial of OAR and EVAR in patients with ruptured AAA . CT scanning does not delay treatment The objective of the Amsterdam Acute Aneurysm Trial is to study the combined outcome of conventional emergency surgery versus endovascular treatment for ruptured abdominal aortic aneurysms . The design used was a multicenter r and omized clinical trial conducted in two university hospitals and one teaching hospital in the Amsterdam region . The study included all patients with a ruptured abdominal aneurysm who were eligible for endovascular and conventional surgery .  The primary end points were combined mortality and severe morbidity . The secondary end points were quality of life and cost-effectiveness . The background , design , and methods of this trial are presented , and the ethical and legal issues of this type of research are discussed INTRODUCTION acute haemodynamic changes and /or loss of abdominal muscle tone can occur during induction of general anaesthesia and may be the Achilles ' tendon in endovascular aneurysm repair ( EVAR ) of ruptured aortoiliac aneurysms ( rAIA ) . The purpose of this study was to evaluate the use of local anaesthesia ( LA ) for EVAR to overcome these limitations . METHODS twenty-one consecutive patients with rAIA are included in this study . Twenty patients underwent EVAR under LA  , and 1 patient was treated under general anaesthesia .  Haemodynamics were stabilised during assessment of EVAR feasibility by CT-scan and during the procedure itself by controlled hypotension ( MAP 50 - 60 mmHg ) and moderate fluid resuscitation . RESULTS median procedure time was 120 min . Haemodynamics remained stable in all but 3 patients who required transfemoral balloon occlusion of the supra-renal aorta . Perioperative intubation was necessary in 5 patients because of respiratory distress ( n=3 ) , or retroperitoneal access ( n=2 ) . Temporary deterioration of renal function occurred in 6 patients , with 2 requiring hemofiltration . CT-scan confirmed sealing of the rAIA in all patients at discharge . 30-day mortality was 9.5 % ( 2 deaths ) . In the median follow-up of 19 months , there were no deaths , but 3 endovascularre- interventions , 1 crossover femoro-femoral bypass , and 1 open surgical graft repair . DISCUSSION our series is the first to show that EVAR for rAIA can be safely performed under LA . This approach allows implantation of commercially available bifurcated SG and improves patient outcome BACKGROUND Although endovascular aneurysm repair ( EVAR ) has a lower 30-day operative mortality than open repair , the long-term results of EVAR are uncertain . We instigated EVAR trial 1 to compare these two treatments in terms of mortality , durability , health-related quality of life ( HRQL ) , and costs for patients with large abdominal aortic aneurysm ( AAA ) . METHODS We did a r and omised controlled trial of 1082 patients aged 60 years or older who had aneurysms of at least 5.5 cm in diameter and who had been referred to one of 34 hospitals proficient in the EVAR technique .  We assigned patients who were anatomically suitable for EVAR and fit for an open repair to EVAR ( n=543 ) or open repair ( n=539 ) . Our primary endpoint was all-cause mortality , with secondary endpoints of aneurysm related mortality , HRQL , postoperative complications , 
    Output:
    
For complication outcomes that did include at least 2 studies in the meta- analysis , there was no clear evidence to support a difference between eEVAR and open repair .
Outcomes between eEVAR and open repair , specifically 30-day mortality , are similar .