***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: 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 BACKGROUND Although the initial results of endovascular repair of abdominal aortic aneurysms were promising , current evidence from controlled studies does not convincingly show a reduction in 30-day mortality relative to that achieved with open repair . METHODS We conducted a multicenter , r and omized trial comparing open repair with endovascular repair in 345 patients who had received a diagnosis of abdominal aortic aneurysm of at least 5 cm in diameter and who were considered suitable c and i date s for both techniques . The outcome events analyzed were operative ( 30-day ) mortality and two composite end points of operative mortality and severe complications and operative mortality and moderate or severe complications . RESULTS The operative mortality rate was 4.6 percent in the open-repair group ( 8 of 174 patients ; 95 percent confidence interval , 2.0 to 8.9 percent ) and 1.2 percent in the endovascular-repair group ( 2 of 171 patients ; 95 percent confidence interval , 0.1 to 4.2 percent ) , result ing in a risk ratio of 3.9 ( 95 percent confidence interval , 0.9 to 32.9 ) . The combined rate of operative mortality and severe complications was 9.8 percent in the open-repair group ( 17 of 174 patients ; 95 percent confidence interval , 5.8 to 15.2 percent ) and 4.7 percent in the endovascular-repair group ( 8 of 171 patients ; 95 percent confidence interval , 2.0 to 9.0 percent ) , result ing in a risk ratio of 2.1 ( 95 percent confidence interval , 0.9 to 5.4 ) . CONCLUSIONS On the basis of the overall results of this trial , endovascular repair is preferable to open repair in patients who have an abdominal aortic aneurysm that is at least 5 cm in diameter . Long-term follow-up is needed to determine whether this advantage is sustained OBJECTIVES to assess the early morbidity and mortality of a new treatment , the endovascular repair of abdominal aortic aneurysms  , during its introduction into clinical practice . DESIGN a prospect i ve voluntary registry collecting demographic and risk factor data , details of aneurysm morphology , procedure performed , immediate and 30-day outcomes . SETTING thirty-one U.K. centres performing endovascular repair su bmi tted data . RESULTS six hundred and eleven cases were registered in three years of data collection ( January 1996 to December 1998 ) . Four per cent of patients received an aortic tube device , 60 % an aorto-bi-iliac device and 36 % an aorto-uni-iliac device and a crossover graft ( AUIC ) .  Conversion to open repair was required in 5 % of cases , with more conversions in the AUIC group ( OR 2.9 ( 95 % CI : 1.3 - 6.4)p=0.01 ) . Post procedure complications occurred in 25 % of cases . Unfit patients had significantly more complications than fit patients ( 35 % vs 20 % for fit patients ( OR 1.8 ( 95 % CI : 1.2 - 2.7)p=0.007 ) ) . At 30 days aneurysms were excluded in 90 % of cases . Endoleaks were more common in larger aneurysms ( 2 % if aneurysms were < 6 cm in diameter vs 10 % if > 6 cm , OR 5.6 ( 95 % CI : 2.1 - 14.9)p=0.0006 ) . The overall mortality was 7 % but was significantly higher for AUIC devices , ( 4 % for combined aortic tube and bi-iliac devices ( AT/BI ) vs 12 % , OR 2.6 ( 95 % CI : 1.2 - 5.9 p=0.018 ) ) , and unfit patients ( 4 % for fit patients vs 18 % , OR 4.3 ( 95 % CI : 2.0 - 9.5)p<0.001 ) . CONCLUSIONS endovascular repair is feasible with short-term outcomes comparable to those of conventional surgical repair . In unfit patients the possible benefit in life expectancy gain must be balanced against the morbidity and mortality of the procedure OBJECTIVES To assess the mid-term outcomes up to 5 years following  endovascular repair of abdominal aortic aneurysms ( EVAR ) , following its initial introduction into practice in the UK . DESIGN A prospect i ve voluntary Registry of Endovascular Treatment of Aneurysms ( RETA ) collected demographic and risk factor data , short term ( 30 day ) outcomes and follow up outcomes up to 5 years from the 41 centres that initially undertook EVAR in the UK . RESULTS Short term outcomes ( 30 days ) : 90.4 % of aneurysms were successfully excluded , 6.1 % had persistent endoleaks and 5.8 % of patients had died . Follow up was obtained from 30 days up to 5 years ( mean 3.1 years ) . Returns rates for requested follow up data were 87 % at 1 year and 77 , 65 , 52 and 51 % at 2 , 3 , 4 and 5 years , respectively . Ninety percent of deaths at follow up were unrelated to the stent-graft or aneurysm . Persistent proximal type I endoleak was associated with significant mortality both from attempted open repair or from rupture if untreated . Other endoleaks were more benign . Complications related to the aneurysm or device occurred at an average rate of 15 % per annum . The most common complications were secondary endoleaks or graft migration . Endovascular treatment was preferred if treatment was necessary for graft complications . The cumulative freedom from secondary procedure ( Kaplan-Meier ) were 87 , 77 , 70 , 65 and 62 % at 1 , 2 , 3 , 4 and 5 years of follow up , respectively . CONCLUSIONS Registry data provides useful information to guide the design of more formal trials . Collecting follow up from voluntarily su bmi tted data is difficult . The registry data remains well ahead of the trial data , but indicate that long term follow up is required in these trials , because of the high rate of complications seen at follow up PURPOSE To compare functional autonomy , quality of life ( QOL ) , and pain control after  endovascular and open repair ( OR ) of abdominal aortic aneurysms . MATERIAL S AND METHODS Forty patients with a low surgical risk profile and anatomic compatibility for stent-graft therapy were r and omized to receive OR or endovascular aneurysm repair ( EVAR ) .  Technical and clinical success as well as mortality were assessed in both groups and compared by Kaplan-Meier analysis . Functional autonomy and QOL were assessed by Karnofsky score and Short Form 36 ( SF-36 ) question naire . Pain control was assessed by a numeric rating scale and Brief Pain Inventory question naire . QOL outcomes by means of the SF-36 and pain question naires were compared with use of mixed-effects models for repeated- measures analysis . RESULTS All procedures were technically successful in both groups . Three late clinical failures requiring surgical conversion or repeated intervention were observed in the EVAR group and one was observed in the OR group . There was no significant difference between groups in terms of functional autonomy or QOL . No difference in pain level was evident during the early postoperative period , whereas the pain level was lower in the OR group after 1 month . Opioid analgesic drug consumption was significantly greater in the OR group during the postoperative period . Mean hospitalization duration was shorter in the EVAR group than in the OR group ( 4.5 days + /- 2.4 vs 11.5 days + /- 8.1 ; P= .001 ) . CONCLUSION EVAR has no advantage over OR in patients at low risk in terms of functional autonomy , QOL , and pain control . However , EVAR was associated with shorter hospitalization duration s compared with OR 
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A comparison of outcomes across all studies did not support the hypothesis that the findings of the RCTs are no longer representative of clinical practice .
Both r and omised and non-r and omised sources of evidence have strengths and weaknesses for assessing the effectiveness of EVAR .