***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 AND OBJECTIVES Prognosis and in-hospital management of patients with acute coronary syndrome ( ACS ) and a history of coronary artery bypass graft ( CABG ) surgery  are still debated . The objective of this study was to characterize ACS patients with a CABG  and to compare their in-hospital and postdischarge outcomes with those of patients without a  CABG  . METHODS This ongoing prospect i ve observational study included 1,495 consecutive patients admitted for ACS to a coronary care unit and followed up for a mean of 19 months . There were two groups : group A ( n=73 ) , with CABGs ; and group B ( n=1,223 ) , without CABGs . RESULTS Group A patients were more often male ( 86.3 % versus 69.1 % ; P=.002 ) , and more frequently had a history of diabetes , myocardial infa rct ion and heart failure . Group B patients more frequently had ST-elevation myocardial infa rct ion , and had a higher median ejection fraction ( 53 % [ interquartile range , 47%-60 % ] vs. 50 % [ 42%-55 % ] ; P < .01 ) and peak troponin-I concentration . There was no difference in the use of invasive techniques . Regarding medication , Group B patients were more likely to receive  dual antiplatelet therapy at discharge . No significant difference was observed in in-hospital mortality ( 9.5 % versus 5.9 % ; P=.2 ) or mortality at 1 month , 6 months or 1 year ( 9.8 % versus 9.1 % ; log-rank test , P=.87 ) and the cumulative major adverse cardiac event rate was equally low in both groups . The presence of a CABG was associated with more readmissions for unstable angina ( 11.3 % vs. 3.1 % ; P < .01 ) . CONCLUSIONS In our ACS patients , the presence of a CABG had no significant influence on short- or medium-term outcomes , such as all-cause mortality and adverse cardiac events ST-segment elevation acute myocardial infa rct ion ( AMI ) in patients who have undergone previous coronary artery bypass grafting ( CABG ) is associated with low reperfusion rates and poor outcome after fibrinolytic therapy . The efficacy of a combination strategy ( reduced fibrinolytic plus platelet glycoprotein IIb/IIIa agent ) in this setting is unknown . In the Global Use of Streptokinase and TPA for Occluded coronary arteries V ( GUSTO V ) trial , 553 patients with a history of CABG were treated with st and ard-dose reteplase ( n = 273 ) , or half-dose reteplase and full-dose abciximab ( n = 280 ) in the first 6 hours of evolving ST-segment elevation MI . Mortality at 30 days was significantly higher in patients who underwent prior CABG compared with patients with no prior CABG ( odds ratio [ OR ] 1.64 , 95 % confidence interval [ CI ] 1.21 to 2.24 , p = 0.001 ) . In patients who underwent prior CABG , mortality at 7 days was reduced 15 % with combination therapy compared with reteplase alone , which was not statistically significant ( OR 0.85 , 95 % CI 0.40 to 1.81 , p = 0.66 ) . Patients who underwent prior CABG treated with the combination therapy had fewer episodes of recurrent ischemia ( OR 0.60 , 95 % CI 0.37 to 0.96 , p = 0.02 ) , high degree atrioventricular block ( OR 0.17 , 95 % CI 0.02 to 0.82 , p = 0.01 ) , and ventricular tachycardia ( OR 0.29 , 95 % CI 0.07 to 0.96 , p = 0.04 ) . There was a trend toward reduced urgent revascularization ( OR 0.61 , 95 % CI 0.36 to 1.03 , p = 0.06 ) but no significant difference in reinfa rct ion ( OR 0.61 , 95 % CI 0.31 to 1.52 , p = 0.40 ) . In the GUSTO V trial , patients who underwent prior CABG had significantly higher event rates compared with patients without CABG . As in the overall trial , combination therapy in patients who underwent prior CABG led to a consistent reduction in key secondary complications of AMI , including recurrent ischemia and a trend toward reduced urgent revascularization The aim of this study was to characterize patients with and without prior coronary artery bypass grafting ( CABG ) among a prospect ively identified cohort of patients presenting with unstable angina or non-Q-wave myocardial infa rct ion . Patients in the Thrombolysis in Myocardial Infa rct ion phase III Registry Prospect i ve Study presented within 96 hours of an episode of unstable angina or non-Q-wave acute myocardial infa rct ion . Of 2,048 patients , 336 ( 16.4 % ) had prior CABG .  Compared with those without prior CABG , patients were the same age , but were more likely to be men , white , diabetic , have a history of angina or myocardial infa rct ion , to have received anti-ischemic medications in the prior week , and to receive intravenous heparin or nitroglycerin  , or both , during hospitalization . They were equally likely to undergo coronary angioplasty or CABG .  Death or nonfatal myocardial infa rct ion occurred by day 10 in 4.5 % of patients with prior CABG and 2.8 % of patients without prior CABG ( p = 0.11 ) ; and by day 42 in 7.7 % and 5.1 % , respectively ( p = 0.03 ) . The composite of death , myocardial infa rct ion , or recurrent ischemia at 1 year was more common among patients with prior CABG ( 39.3 % vs 30.2 % , p = 0.002 ) . By multiple logistic regression , prior CABG was not independently associated with the occurrence of death or myocardial infa rct ion , or the composite of death , myocardial infa rct ion , or recurrent ischemia either at 6 weeks or at 1 year . The likelihood of recurrent ischemic events is greater among patients with than without prior  CABG , but is not likely explained by differences in baseline or treatment characteristics which reflect the degree of underlying cardiac disease Background — Patients with prior CABG with a subsequent non – ST-segment elevation acute coronary syndrome ( ACS ) pose an increasingly important clinical problem . Although GP IIb/IIIa inhibitors have improved the outcome of patients with ACS , their efficacy in patients with prior CABG has not been previously evaluated . Methods and Results —We analyzed the 30- and 180-day outcomes of patients with prior CABG enrolled in the Platelet Glycoprotein IIb/IIIa in Unstable Angina : Receptor Suppression Using Integrilin Therapy ( PURSUIT ) trial . In this trial , which evaluated the efficacy of eptifibatide in patients with ACS , 1134 patients ( 12 % ) with prior CABG and 8321 without prior CABG were enrolled . After adjusting for differences in baseline characteristics and treatment , patients with prior CABG had a significantly higher mortality rates at 30 days ( hazard ratio [ HR ] , 1.45 [ 95 % CI , 1.06 to 1.98];P = 0.019 ) and at 180 days ( HR , 1.32 [ 95 % CI , 1.04 to 1.67];P = 0.021 ) . At 30 days , there was a similar effect on the primary end point of death or myocardial infa rct ion in the eptifibatide group versus the placebo group in prior CABG patients ( unadjusted HR , 0.90 [ 95 % CI , 0.67 to 1.20 ] ) and in patients without a history of CABG ( unadjusted HR , 0.89 [ 95 % CI , 0.80 to 0.99 ] ) . Conclusions — Patients with prior CABG with non – ST-segment elevation ACS have a significantly worse prognosis than do patients without a history of CABG . The treatment effect of eptifibatide in the prior CABG group was similar to the effect seen in patients without prior CABG OBJECTIVES We sought to compare outcomes in  ST-segment elevation myocardial infa rct ion ( STEMI ) patients undergoing primary percutaneous coronary intervention ( PCI ) with or without previous coronary artery bypass grafts ( CABG ) .  BACKGROUND Limited information exists regarding procedural success and clinical outcomes of STEMI patients with CABG undergoing primary PCI . METHODS The APEX-AMI ( Assessment of Pexelizumab in Acute Myocardial Infa rct ion ) trial was a r and omized , placebo-controlled trial of pexelizumab in STEMI patients with planned primary PCI : 128 of 5,745 ( 2.2 % ) patients had prior CABG .  Clinical /procedural characteristics , culprit vessel ( infa rct -related artery [ IRA ] ) , and 90-day clinical outcomes were compared . RESULTS Patients with previous CABG were more frequently men , older , had a higher incidence of comorbidities and multivessel disease . In patients with versus without prior CABG , PCI was performed less frequently , that is , 78.9 % versus 93.9 % ; of those with prior CABG receiving PCI , Thrombolysis In Myocardial Infa rct ion ( TIMI ) flow grade 3 was also restored less often , that is , 82.5 % versus 91.6 % ( both p < 0.001 ) . In prior CABG , there was a nearly even design ation of the IRA as a bypass graft ( n = 63 ) versus a native vessel ( n = 55 ) : IRA post-PCI TIMI flow grade 3 was achieved in 66.7 % versus 88.0 % , respectively ( p = 0.043 ) . Prior CABG patients had increased 90-day death and composite 90-day death/congestive heart failure/shock . Excess death remained significant after multivariable adjustment ( hazard ratio : 1.9 , 95 % confidence interval : 1.08 to 3.33 , p = 0.025 ) . When prior CABG patients were stratified by the type of IRA , there was further discrimination of the increased 90-day death , that is , 19 % bypass graft ( n = 63 ) versus 5.7 % native vessel ( n = 55 , p = 0.05 ) , respectively . CONCLUSIONS Prior CABG patients with STEMI are less likely to undergo acute reperfusion , have worse angiographic outcomes following primary PCI , and higher 90-day mortality . These findings are especially applicable when the IRA was a bypass graft BACKGROUND Patients with previous coronary artery bypass graft surgery ( CABG )  have been classified as a high-risk subset of patients who experience non-ST elevation acute coronary syndrome ( ACS ) . Recent studies suggest that an early invasive strategy is beneficial in moderate- and high-risk patients with non-ST elevation ACS . We hypothesized that an early invasive strategy is associated with improved outcomes in patients with non-ST elevation ACS with prior CABG .  METHODS AND RESULTS In the Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy -Thrombolysis in Myocardial Infa rct ion 18 trial ( TACTICS-TIMI 18 ) , 2220 patients with non-ST segment elevation ACS were r and omized to an early invasive or conservative ( selectively invasive ) strategy . All patients were treated with aspirin , heparin , and tirofiban .  Four hundred eighty-four ( 22 % ) of these patients had undergone CABG before enrollment . We analyzed whether patients with previous CABG had different 6-month outcomes and whether an early invasive strategy was associated with an improvement in long-term outcomes . Prior CABG was associated with a higher risk of adverse outcomes by 6 months , including a higher rate of readmission for ACS ( 17.4 % vs 11.0 % , P < 0.001 ) and a higher incidence of the composite end point of death , myocardial infa rct ion , or rehospitalization for ACS ( 22.3 % vs 16.4 % , P = 0.002 ) . There was a trend toward a higher incidence of myocardial infa rct ion ( 7.1 % vs 5.3 % , P = 0.051 ) . An early invasive strategy was associated with a reduction in the composite of death or myocardial infa rct ion ( odds ratio [ OR ] , 0.58 ; 95 % confidence interval [ CI ] , 0.31 - 1.0 ; P = 0.089 ) and a significant reduction in the incidence of myocardial infa rct ion at 6 months ( OR , 0.44 ; 95 % CI , 0.21 - 0.93 ; P=0.032 ) . CONCLUSIONS Patients with non-ST 
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Both the in-hospital and the long-term re-infa rct ion rates were higher for the previous CABG ACS patients .
Conclusions : According to our data , ACS patients with previous CABG history had a higher risk for short- and long-term adverse events