***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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    ***EXAMPLES*** 
    Input: BACKGROUND Percutaneous treatment of patients with ST segment elevation myocardial infa rct ion ( STEMI ) has become the st and ard and default mode of management as recommended by the European Society of Cardiology guidelines for managing acute myocardial infa rct ion in patients presenting with STEMI . The choice of vascular access is made by the operator and has a potential impact on the safety and efficacy of the procedure and outcomes . AIM To underst and the influence of a radial approach on bleeding complications and angiographic success , we performed a prospect i ve , controlled r and omised trial . METHODS Patients were allocated to radial ( TR ) or femoral ( TF ) vascular access . The primary endpoints were major bleeding by the REPLACE-2 scale and minor bleeding by the EASY scale ( TR arm ) or the FEMORAL scale ( TF arm ) . Other outcomes included procedural data , in-hospital and long-term survival . RESULTS There were 103 patients analysed in total , 52 in the TR arm and 51 in the TF arm . The demographic and clinical baseline characteristics were well matched between the two study groups . The frequency of the primary endpoint was the same in both arms ( TR : 25.0 % vs. TF : 33.3 % , p = 0.238 ) . In per protocol analysis , there was a significant benefit of the TR approach among independent operators ( 17.4 % vs. 36.8 % , p = 0.038 ) . Major bleeding by the REPLACE-2 scale occurred in 4.2 % of patients ( TR : 5.8 % vs. TF : 3.9 % , p = 0.509 ) . There were no differences in terms of the rate of major cardiac adverse events , which happened in 10.7 % of the study population ( TR : 9.6 % vs. TF : 11.8 % , p = 0.48 ) . In the TF arm , there was a trend towards a higher risk of local bleedings ( TR : 22.4 % vs. TF : 37.7 % , p = 0.081 ) and a significantly higher frequency of local haematoma ( class III , EASY/FEMORAL ) ( TR : 0 % vs. TF : 9.8 % , p = 0.027 ) . CONCLUSIONS There were no significant differences between the TR and TF approaches in terms of clinical efficacy and patient safety . However , patients treated by independent operators might benefit from TR access . The overall complication risk of percutaneous coronary intervention treatment of STEMI patients remains low OBJECTIVES The purpose of this study was to assess whether transradial access for ST-segment elevation acute coronary syndrome undergoing early invasive treatment is associated with better outcome compared with conventional transfemoral access . BACKGROUND In patients with acute coronary syndrome , bleeding is a significant predictor of worse outcome . Access site complications represent a significant source of bleeding for those patients undergoing revascularization , especially when femoral access is used . METHODS The RIFLE-STEACS ( Radial Versus Femoral R and omized Investigation in ST-Elevation Acute Coronary Syndrome ) was a multicenter , r and omized , parallel-group study . Between January 2009 and July 2011 , 1,001 acute ST-segment elevation acute coronary syndrome patients undergoing primary /rescue percutaneous coronary intervention  were r and omized to the radial ( 500 ) or femoral ( 501 ) approach at 4 high-volume centers . The primary endpoint was the 30-day rate of net adverse clinical events ( NACEs ) , defined as a composite of cardiac death , stroke , myocardial infa rct ion , target lesion revascularization , and bleeding ) . Individual components of NACEs and length of hospital stay were secondary endpoints . RESULTS The primary endpoint of 30-day NACEs occurred in 68 patients ( 13.6 % ) in the radial arm and 105 patients ( 21.0 % ) in the femoral arm ( p = 0.003 ) . In particular , compared with femoral , radial access was associated with significantly lower rates of cardiac mortality ( 5.2 % vs. 9.2 % , p = 0.020 ) , bleeding ( 7.8 % vs. 12.2 % , p = 0.026 ) , and shorter hospital stay ( 5 days first to third quartile range , 4 to 7 days ] vs. 6 [ range , 5 to 8 days ] ; p = 0.03 ) . CONCLUSIONS Radial access in patients with ST-segment elevation acute coronary syndrome is associated with significant clinical benefits , in terms of both lower morbidity and cardiac mortality . Thus , it should become the recommended approach in these patients , provided adequate operator and center expertise is present . ( Radial Versus Femoral Investigation in ST Elevation Acute Coronary Syndrome [ RIFLE-STEACS ] ; NCT01420614 ) Although transradial angioplasty has been shown to have no major entry site – related complications , its clinical applicability for balloon angioplasty and stenting in acute myocardial infa rct ion ( AMI ) is unclear . In order to assess the feasibility , safety , and clinical outcome of transradial access for coronary angioplasty ( PTCA ) and stenting during AMI , transradial angioplasty for AMI was registered on a prospect i ve data base at two European sites ( A and B ) with experience in the radial approach ( RA ) ; 6 Fr catheters with an inner lumen of at least 0.064″ and low‐profile rapid‐exchange balloons were used . Primary success rates and procedural complications of 6 Fr RA were determined and compared to 6 Fr femoral approach ( FA ) procedures . A total of 1,224 AMI patients entered the registry . Study site A enrolled 185 RA patients ( 13.6 % AMI ) and study site B 92 RA patients ( 63.4 % ) . Patient baseline demographics were similar in both study centers and showed no differences between RA and FA patients , except a more frequent use of abciximab in study site B compared to A. PTCA was successful in > 95 % of both RA and FA patients . Total procedural time did not differ between RA and FA patients . Severe access site – related bleeding complications , however , were observed in FA patients only : study site A used closure devices routinely and found 2 % severe bleedings ; study site B used no closure device for FA patients and observed 7 % severe bleedings . In selected patients and in experienced h and s , transradial PTCA in AMI has a high success rate , is clinical ly safe , and could become an attractive alternative access site for patients being at high or even low risk for bleeding complications . Cathet Cardiovasc Intervent 2002;55:206–211 . © 2002 Wiley‐Liss , Transradial coronary intervention ( TRI ) can be performed in elective patients with low incidence of access site complications . However , the feasibility of primary stent implantation by TRI is still not clear in patients with acute myocardial infa rct ion ( AMI ) . We prospect ively r and omized 149 patients out of 213 patients with AMI within 12 hr from onset into two groups : 77 patients treated by TRI ( TRI group ) and 72 patients by transfemoral coronary intervention ( TFI ; TFI group ) . We compared the incidences of major adverse cardiac events ( MACE ; repeat MI , target lesion revascularization , and cardiac death ) during the initial hospitalization and 9‐month follow‐up periods in both groups . There were one patient who crossed over to the opposite arm , and two patients with severe bleeding complications in the TFI group . Background characteristics of patients were similar between the two groups . The success rate of reperfusion and the incidence of in‐hospital MACE were similar in both groups ( 96.1 % and 5.2 % vs. 97.1 % and 8.3 % in TRI and TFI groups , respectively ) . In selected patients with AMI  , primary stent implantation  by TRI is feasible as compared to TFI . Cathet Cardiovasc Intervent 2003;59:26–33 . © 2003 Wiley‐Liss , CONTEXT It is unclear if blood transfusion in anemic patients with acute coronary syndromes is associated with improved survival . OBJECTIVE To determine the association between blood transfusion and mortality among patients with acute coronary syndromes who develop bleeding , anemia , or both during their hospital course . DESIGN , SETTING , AND PATIENTS We analyzed 24,112 enrollees in 3 large international trials of patients with acute coronary syndromes ( the GUSTO IIb , PURSUIT , and PARAGON B trials ) . Patients were grouped according to whether they received a blood transfusion during the hospitalization . The association between transfusion and outcome was assessed using Cox proportional hazards modeling that incorporated transfusion as a time-dependent covariate and the propensity to receive blood , and a l and mark analysis . MAIN OUTCOME MEASURE Thirty-day mortality . RESULTS Of the patients included , 2401 ( 10.0 % ) underwent at least 1 blood transfusion during their hospitalization . Patients who underwent transfusion were older and had more comorbid illness at presentation and also had a significantly higher unadjusted rate of 30-day death ( 8.00 % vs 3.08 % ; P<.001 ) , myocardial infa rct ion ( MI ) ( 25.16 % vs 8.16 % ; P<.001 ) , and death/MI ( 29.24 % vs 10.02 % ; P<.001 ) compared with patients who did not undergo transfusion . Using Cox proportional hazards modeling that incorporated transfusion as a time-dependent covariate , transfusion was associated with an increased hazard for 30-day death ( adjusted hazard ratio [ HR ] , 3.94 ; 95 % confidence interval [ CI ] , 3.26 - 4.75 ) and 30-day death/MI ( HR , 2.92 ; 95 % CI , 2.55 - 3.35 ) . In the l and mark analysis that included procedures and bleeding events , transfusion was associated with a trend toward increased mortality . The predicted probability of 30-day death was higher with transfusion at nadir hematocrit values above 25 % . CONCLUSIONS Blood transfusion in the setting of acute coronary syndromes is associated with higher mortality , and this relationship persists after adjustment for other predictive factors and timing of events . Given the limitations of post hoc analysis of clinical trials data , a r and omized trial of transfusion strategies is warranted to resolve the disparity in results between our study and other observational studies . We suggest caution regarding the routine use of blood transfusion to maintain arbitrary hematocrit levels in stable patients with ischemic heart disease BACKGROUND The transradial approach for percutaneous coronary intervention ( PCI ) seems to be superior to transfemoral . The safety and efficacy of transradial approach for PCI in acute myocardial infa rct ion is not well-established . METHODS Hundred patients with acute myocardial infa rct ion qualified to PCI  were r and omly assigned to transradial ( group I ; n = 50 ) and transfemoral ( group II ; n = 50 ) approaches . RESULTS PCI was successful for almost all patients , except one from group II . There were no significant differences between groups in X-ray exposition , volume of contrast and total procedure duration . Small but significant elongation of door to stent time in group I was caused mostly by a longer time between beginning of procedure and arterial sheath introduction . Major bleeding complications occurred in three patients from group I and seven from group II . There were no significant differences observed between the two groups . Time to ambulation in group I was significantly shorter then in group II ( 22.6 + /- 10.3 h vs. 34.7 + /- 34.6 h ; p = 0.003 ) . CONCLUSIONS The transradial approach for PCI in acute myocardial infa rct ion has the same efficacy as transfemoral . There are no differences in total procedure duration , X-ray exposition or volume of contrast between the two approaches . A longer time from the patient 's admission to the individual stages of the PCI procedure in group I was mostly due to the longer times of the initial stages of the procedure . The use of transradial approach reduces the time to ambulation and allows rehabilitation to begin sooner . In both groups , bleeding complications occurred rarely BACKGROUND Transradial percutaneous coronary intervention ( PCI ) results in fewer vascular complications , earlier ambulation , and improved patient comfort . Limited data exist for radial access in acute myocardial infa rct ion , where reperfusion must occur quickly . METHODS In a multicenter pilot trial , 50 patients with myocardial infa rct ion requiring either primary or rescue PCI  were r and omized to radial or femoral access . All operators had previously performed at least 100 transradial cases . Procedure times were prospect ively recorded . RESULTS Thrombolysis was used in 66 % of the cases and glycoprotein IIb/IIIa inhibitors in 94 % . Crossover from radial to femoral access was required in one case . Percutaneous coronary intervention was performed in 47 patients , with stenting in 45 . One procedural failure occurred with radial access because of inability to cross the occlusion . The time from local anesthesia to first balloon inflation was 32 ( 25th percentile 26 , 75th percentile 38 ) minutes for radial access and 26 ( 22 , 33 ) minutes for femoral access ( P = .04 ) . There were 
    Output:
    
Based on this large meta- analysis , RA for primary PCI in the setting of ACS is associated with reduction in cardiac and safety endpoints when compared with FA in both urgent and elective procedures .