Lack of clopidogrel pretreatment effect on the relative efficacy of bivalirudin with provisional glycoprotein IIb/IIIa blockade compared to heparin with routine glycoprotein IIb/IIIa blockade: a REPLACE-2 substudy

OBJECTIVES: The purpose of this study was to assess if clopidogrel pretreatment affects the relative efficacy of bivalirudin versus heparin with glycoprotein (GP) IIb/IIIa blockade for percutaneous coronary interventions (PCI). BACKGROUND: Although thienopyridine pretreatment may improve clinical outcomes with PCI, it is unknown if bivalirudin's efficacy compared with heparin is dependent upon such pretreatment. METHODS: The Randomized Evaluation in Percutaneous coronary intervention Linking Angiomax to reduced Clinical Events (REPLACE-2) trial was a double-blind, triple-dummy, randomized-controlled trial comparing heparin plus routine GP IIb/IIIa blockade (heparin group) with bivalirudin plus provisional GP IIb/IIIa blockade (bivalirudin group) during PCI. The primary end point was a composite of death, myocardial infarction (MI), urgent revascularization at 30 days, and major in-hospital bleeding. The secondary end point was a 30-day composite of death, MI, and urgent revascularization. Clopidogrel pretreatment was encouraged (300 mg loading, 75 mg/day). RESULTS: Of 6,010 patients enrolled, 5,893 received clopidogrel, with 85.8% in the bivalirudin and 84.6% in the heparin group receiving clopidogrel pretreatment. Bivalirudin (provisional GP IIb/IIIa blockade 7.2%) was noninferior to the heparin group for both primary and secondary end points. Clopidogrel pretreatment did not affect the relative efficacy of bivalirudin versus heparin with GP IIb/IIIa blockade, irrespective of pretreatment duration. Pretreatment was associated with significantly lower primary end point with bivalirudin (8.7% pretreatment vs. 12.9% no pretreatment, p = 0.007), and nonsignificantly with heparin (9.7% vs. 11.7%, respectively, p = 0.20). Multivariable models showed a trend toward lower primary and secondary end points with clopidogrel pretreatment. CONCLUSIONS: Clopidogrel pretreatment at the doses and time administered in this trial did not influence the relative efficacy of bivalirudin versus heparin plus GP IIb/IIIa blockade for PCI. However, pretreatment was associated with a trend towards lower clinical events after PCI.     

Direct thrombin inhibition appears to be a safe and effective anticoagulant for percutaneous bypass graft interventions.

BACKGROUND: Percutaneous coronary interventions (PCI) of coronary artery bypass grafts (CABG) are associated with worse outcomes compared with those of native coronary PCI. Little is known concerning the use of direct thrombin inhibition during CABG intervention. The objective of this report is to examine the safety and efficacy of bivalirudin with GPIIb/IIIa blockade inhibition in patients undergoing CABG PCI. GP IIb/IIIa use was provisional in REPLACE-2 and planned in REPLACE-1. METHODS AND RESULTS: A post hoc analysis of patients undergoing CABG PCI in the REPLACE-1 and -2 trials was performed. In REPLACE-1, patients were randomized to either heparin or bivalirudin, with GP IIb/IIIa inhibitor use at the operator's discretion. In REPLACE-2, patients were randomized to heparin plus GP IIb/IIIa inhibition versus bivalirudin with provisional GP IIb/IIIa blockade. In both studies, randomized treatment groups were well matched. In unadjusted and logistic regression analysis, there were no significant differences in the combined endpoint of death, myocardial infarction, urgent revascularization, or major bleeding when patients were treated with either heparin or bivalirudin. Individual safety and efficacy endpoints were also similar. Minor bleeding was significantly reduced in patients treated with bivalirudin (14.8% vs. 22.7%, P = 0.037). Follow-up data available from the REPLACE-2 trial at 12 months found similar efficacy between groups with a trend towards decreased 12 month mortality in the bivalirudin vs. heparin groups (4.2% vs. 7.8%, P = 0.16). CONCLUSION: CABG PCI using bivalirudin with provisional GPIIb/IIIa inhibition appears to provide similar safety and efficacy to heparin with GPIIb/IIIa inhibition.     

Bivalirudin in PCI: an overview of the REPLACE-2 trial

The Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE)-2 trial is one of the largest acute randomized controlled trials evaluating the efficacy of two anticoagulant strategies during contemporary urgent or elective percutaneous coronary intervention (PCI). The direct thrombin inhibitor, bivalirudin, with provisional use of glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitor was compared to low-dose unfractionated heparin (UFH) plus planned GP IIb/IIIa inhibitor. At 30-day follow-up, the primary quadruple composite endpoint (death, myocardial infarction (MI), urgent repeat revascularization, or in-hospital major bleeding) occurred in 9.2% of patients in the bivalirudin group versus 10.0% of patients in the UFH plus GP IIb/IIIa inhibitor group. The secondary triple composite endpoint (death, MI, urgent repeat revascularization) occurred in 7.6% of patients in the bivalirudin group compared with 7.1% of patients in the UFH plus GP IIb/IIIa inhibitor group. Both endpoints met formal statistical criteria for noninferiority to UFH plus GP IIb/IIIa inhibitor. By imputed comparison from historic GP IIb/IIIa trials between bivalirudin versus UFH alone, REPLACE-2 demonstrated that bivalirudin was superior to UFH alone with respect to the quadruple and triple composite endpoints. Furthermore, bivalirudin plus provisional GP IIb/IIIa blockade was associated with a significant reduction in in-hospital bleeding (2.4% vs. 4.1%; p < 0.001). At 6 months' follow-up, there was no significant difference in rates of death, MI, or revascularization between the two groups. Furthermore, there was no evidence that the early, nonsignificant 0.5% excess non-Q-wave MI in the bivalirudin group translated into later mortality. There was a trend toward decreased mortality at 6 months in the bivalirudin arm (0.95% vs. 1.35%; p = 0.148). The relative efficacy of bivalirudin versus UFH plus GP IIb/IIIa inhibitor was similar in several high-risk subgroups, including patients with diabetes mellitus or prior MI, women, the elderly (age > 65 years), and patients undergoing PCI of bypass grafts. Bivalirudin represents an exciting alternative to UFH plus GP IIb/IIIa inhibitor in patients undergoing urgent and elective PCI with similar suppression of ischemic events, fewer bleeding complications, and the potential for greater cost savings and ease of administration.     

Debate of adjunctive pharmacology for percutaneous coronary intervention: anticoagulation and clopidogrel are not (always) enough

Substantial controversy exists regarding the optimal pharmacologic cocktail for percutaneous coronary intervention (PCI). The most common approach typically includes aspirin, clopidogrel, unfractionated heparin (or enoxaparin), and (variably) a glycoprotein (GP) IIb/IIIa inhibitor. Some substitute bivalirudin with "bail-out" GP IIb/IIIa blockade for heparin and planned GP IIb/IIIa integrin blockade, an approach that necessarily includes aspirin and clopidogrel (for their antiplatelet effects). These shifts in adjunctive treatment paradigms should be examined in the context of available data from clinical studies. Several studies have demonstrated the phenomenon of clopidogrel resistance to be fairly prevalent; even in clopidogrel-responsive patients, steady state is achieved only 4-6 hours after a 600-mg loading dose. It would thus be anticipated that clopidogrel-resistant patients would benefit from GP IIb/IIIa blockade, particularly during the period immediately after intervention. Neither REPLACE-2 nor the recent ACUITY trial demonstrated an efficacy advantage for bivalirudin as a substitute for heparin plus GP IIb/IIIa blockade; instead, any advantage appears to be limited to reducing the propensity for bleeding. As bleeding is directly correlated with the degree of anticoagulation and is further augmented by GP IIb/IIIa blockade, an alternative to the bivalirudin strategy is to simply reduce the amount of heparin anticoagulation during PCI. Finally, the benefit-to-risk ratio of aggressive adjunctive antiplatelet/antithrombotic therapy might be further improved via risk stratification, with patients at higher risk for periprocedural events receiving intensive therapy and lower-risk patients being managed with less intensive regimens focused on minimizing the risk of bleeding.     

Comparison of bivalirudin versus heparin plus glycoprotein IIb/IIIa inhibitors in patients undergoing an invasive strategy: A meta-analysis of randomized clinical trials

Objective

This meta-analysis was performed to assess the efficacy and safety of bivalirudin compared with unfractionated heparin or enoxaparin plus glycoprotein (GP) IIb/IIIa inhibitors in patients undergoing percutaneous coronary intervention (PCI).

Background

Pharmacotherapy for patients undergoing PCI includes bivalirudin, heparin, and GP IIb/IIIa inhibitors. We sought to compare ischemic and bleeding outcomes with bivalirudin versus heparin plus GP IIb/IIIa inhibitors in patients undergoing PCI.

Methods

A literature search was conducted to identify fully published randomized trials that compared bivalirudin with heparin plus GP IIb/IIIa inhibitors in patients undergoing PCI.

Results

A total of 19,772 patients in 5 clinical trials were included in the analysis (9785 patients received bivalirudin and 9987 patients received heparin plus GP IIb/IIIa inhibitors during PCI). Anticoagulation with bivalirudin, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in no difference in major adverse cardiovascular events (odds ratio [OR] 1.07, 95% confidence interval [CI] 0.96 to 1.19), death (OR 0.93, 95% CI 0.72 to 1.21), or urgent revascularization (OR 1.06, 95% CI 0.86 to 1.30). There is a trend towards a higher risk of myocardial infarction (OR 1.12, 95% CI 0.99 to 1.28) but a significantly lower risk of TIMI major bleeding with bivalirudin (OR 0.55, 95% CI 0.44 to 0.69).

Conclusion

In patients who undergo PCI, anticoagulation with bivalirudin as compared with unfractionated heparin or enoxaparin plus GP IIb/IIIa inhibitors results in similar ischemic adverse events but a reduction in major bleeding.     

Planned versus provisional use of glycoprotein IIb/IIIa inhibitors in smokers undergoing percutaneous coronary intervention

Postmortem and angiographic studies have demonstrated that thrombosis is the primary cause of coronary artery occlusion in smokers. Further, smokers have high levels of fibrinogen, increased platelet aggregation, and more platelet-dependent thrombin generation than do nonsmokers, suggesting that glycoprotein (GP) IIb/IIIa inhibitor use during percutaneous coronary intervention (PCI) may be especially useful among smokers. We evaluated a subpopulation of active smokers in the REPLACE-2 trial to assess the effect of treating smokers with bivalirudin and provisional GP IIb/IIIa blockade compared with heparin and planned GP IIb/IIIa blockade. The REPLACE-2 trial enrolled 1,558 smokers and 4,305 nonsmokers. Smokers who were treated with bivalirudin had an absolute 3.2% increase in the composite end point of death and myocardial infarction at 48 hours compared with smokers who were treated with heparin and GP IIb/IIIa inhibitors (7.7% vs 4.5%, p=0.008, interaction p=0.016). This difference was ameliorated when GP IIb/IIIa inhibitors were used consistently in a previous trial that compared bivalirudin with heparin during PCI (4.6% vs 6.7%, p=0.322). In conclusion, these results suggest that smokers may derive particular benefit with GP IIb/IIIa inhibitors for decreasing myocardial infarction and death after PCI. These findings require further validation from other large, randomized trials.     

Head-to-head comparison of bivalirudin versus heparin without glycoprotein IIb/IIIa inhibitors in patients with acute myocardial infarction undergoing primary angioplasty

BackgroundIn patients receiving primary percutaneous coronary intervention for ST elevation myocardial infarction (STEMI), bivalirudin with provisional glycoprotein (GP) IIb/IIIa inhibitors has been demonstrated to be noninferior to heparin plus systematic GP IIb/IIIa inhibitors in preventing recurrent ischemic events with improved safety in terms of bleeding. However, no study has been performed comparing head-to-head bivalirudin with heparin without GP IIb/IIIa inhibitor infusion in STEMI patients.MethodsWe retrospectively studied 899 consecutive patients who presented with STEMI treated by primary angioplasty within 12 h after symptoms. Among them, 566 received bivalirudin and 333 received unfractionated heparin. Their in-hospital outcome in terms of efficacy and safety was assessed using rates of major adverse cardiac events (MACE) and major bleeding, respectively. Clinical, angiographic and procedural characteristics were well matched between the two groups.ResultsPatients in the heparin group more frequently required intra-aortic balloon pumping (6.6% vs. 3.6%, P=.037). Regarding the safety end point, the MACE rate, including death, ischemic stroke and urgent repeated revascularization, was low and similar in both groups (2.7% bivalirudin vs. 1.2% heparin, P=.15). The rate of major bleeding, including major hematoma, gastrointestinal bleeding and hematocrit drop >15% during hospitalization, was high and identical in the two groups (4.1% bivalirudin vs. 4.2% heparin, P=.92).ConclusionThis study suggests that bivalirudin and heparin present similar safety and efficacy profiles when used without GP IIb/IIIa inhibitor infusion during primary angioplasty.     

Effectiveness and safety of bivalirudin during percutaneous coronary intervention in a single medical center

A recent large-scale, randomized trial demonstrated the noninferiority of a strategy of bivalirudin with provisional glycoprotein (GP) IIb/IIIa inhibition compared with routine GP IIb/IIIa inhibition. There is a paucity of outcome data with bivalirudin use in the setting of real-world experience. We evaluated 6,996 patients who underwent percutaneous coronary intervention between January 2001 and December 2004 to compare early and late outcomes with a bivalirudin-based antithrombotic regimen with those with a heparin-based regimen. Propensity adjustment was performed to correct for baseline differences in patient characteristics. Bivalirudin-based therapy was used in 1,070 patients, heparin only in 801 patients, and heparin plus GP IIb/IIIa inhibitors in 5,125 patients. Compared with patients who received heparin or those who received heparin plus GP IIb/IIIa inhibitors, patients who received bivalirudin had lower incidences of bleeding (blood transfusion rate 1.7% vs 4.0%, p <0.001) and periprocedural myonecrosis (creatine kinase-MB >5 times the upper limit of normal 2.7% vs 4.3%, p = 0.016). Differences in bleeding end points remained significant after adjusting for the propensity to receive bivalirudin, but there was no difference in ischemic events. There was no difference in unadjusted long-term survival rate (log-rank test p = 0.46, total number of deaths 412, mean follow-up 17 months) or in propensity-adjusted long-term survival rate (hazard ratio 1.37, 95% confidence interval 0.90 to 2.08, p = 0.14). Compared with heparin with or without GP IIb/IIIa inhibition, the use of bivalirudin in a large consecutive patient registry at a tertiary care center was associated with fewer bleeding events and no evident increase in the incidence of ischemic complications.     

Efficacy and safety of bivalirudin in patients receiving clopidogrel therapy after diagnostic angiography for percutaneous coronary intervention in acute coronary syndromes

Objectives : This study sought to investigate if the efficacy of bivalirudin monotherapy is similar to heparin plus GP IIb/IIIa inhibition in patients with acute coronary syndromes (ACS) treated with clopidogrel following diagnostic angiography. Background : Prior trials have demonstrated that peri‐procedural bivalirudin therapy confers similar efficacy as heparin plus GP IIb/IIIa inhibitors, while lowering the risk of bleeding complications in ACS patients undergoing percutaneous coronary intervnetions (PCI). However, the incidence of adverse ischemic events post‐PCI appeared to be higher in patients receiving bivalirudin without adequate pretreatment with clopidogrel. Methods : Using the 2004/2005 Cornell Angioplasty Registry, we evaluated 980 consecutive patients undergoing urgent PCI for UA/NSTEMI who were treated with either bivalirudin or UFH plus GP IIb/IIIa inhibitor. We excluded patients who were on chronic clopidogrel therapy or received clopidogrel pretreatment prior to angiography. All patients received a clopidogrel load (≥300‐mg dose) immediately before or after the PCI. Long‐term all‐cause mortality was obtained for 100% of patients, with a mean follow‐up of 24.6 ± 7.7 months. Results : Of the 980 study patients, 461 (47.0%) were treated with bivalirudin and 519 (53.0%) patients received UFH plus GP IIb/IIIa inhibitor. DES were used in 88% of PCI; 45% of patients presented with NSTEMI. The incidence of in‐hospital death (0.4% vs. 0.2%, P = 0.604), post‐procedural MI (6.9% vs. 5.4%, P = 0.351), and MACE including death, stroke, emergent CABG/PCI, and MI (7.6% vs. 5.8%, P = 0.304) were similar in patients treated with bivalirudin versus UFH plus GP IIb/IIIa inhibitors, respectively. The incidence of in‐hospital stent thrombosis was similar (0.7% vs. 0%, P = 0.104), while major (0.9% vs. 2.9%, P = 0.034) and minor bleeding (10.4% vs. 18.9%, P < 0.001) was reduced in the bivalirudin‐treated group. By two‐years of follow‐up, after propensity‐score adjusted multivariate Cox regression analysis, there was no significant difference in long‐term mortality between the two groups (HR 1.18; 95%CI 0.64–2.19, P = 0.598). Conclusions : In patients presenting with ACS and receiving clopidogrel treatment after angiography (before or within 30 min of PCI), peri‐procedural bivalirudin monotherapy suppresses acute and long‐term adverse events to a similar extent as does UFH plus GP IIb/IIIa inhibitors, while significantly lowering the risk of bleeding complications. © 2010 Wiley‐Liss, Inc.     

Angiographic and clinical outcomes of bivalirudin versus heparin in patients with acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND: Heparin with adjunctive glycoprotein IIb/IIIa platelet receptor (GP IIb/IIIa) inhibitors has demonstrated its effectiveness in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). Bivalirudin, a direct thrombin inhibitor, has recently been shown to be an effective alternative for patients undergoing elective PCI. OBJECTIVES: To assess the angiographic and clinical outcomes of adjunctive pharmacological strategies in a high-risk population presenting with ACS. METHODS: Of 891 consecutive PCI patients with ACS, 304 received bivalirudin (60.5% male, 68+/-11 years) and were compared with 283 who received heparin (58.7% male, 66+/-12 years). A 30-day major adverse cardiac event was defined as the occurrence of cardiac death, nonfatal myocardial infarction, urgent revascularization or major hemorrhage. RESULTS: Adjunctive GP IIb/IIIa inhibitors were used in 14.1% of the bivalirudin group and in 72.4% of the heparin group (P<0.010). The occurrence of Thrombolysis In Myocardial Infarction (TIMI) flow less than grade 3 was lower and the achievement of angiographic success was higher in the bivalirudin group than in the heparin group (5.2% versus 8.2%, 94.7% versus 89.7%, P=0.039 and P<0.010, respectively). There was no difference between groups in the incidence of bleeding events (bivalirudin 2.0% versus heparin 3.5%, P not significant) and in 30-day major adverse cardiac events (bivalirudin 8.3% versus heparin 5.7%, P=0.223). CONCLUSIONS: In the high-risk cohort undergoing PCI, bivalirudin with provisional GP IIb/IIIa inhibitors achieved better angiographic results. Although not powered to show a difference, and while acknowledging that a selection bias could have affected the data, the present study showed that bivalirudin may be as clinically effective and safe as heparin with adjunctive GP IIb/IIIa inhibitors.     

Economic evaluation of bivalirudin with provisional glycoprotein IIB/IIIA inhibition versus heparin with routine glycoprotein IIB/IIIA inhibition for percutaneous coronary intervention: results from the REPLACE-2 trial

OBJECTIVES: The purpose of this study was to compare the cost of percutaneous coronary intervention (PCI) using bivalirudin with provisional platelet glycoprotein (GP) IIb/IIIa inhibition with that of heparin + routine GP IIb/IIIa inhibition. BACKGROUND: Although GP IIb/IIIa inhibition has been shown to reduce ischemic complications in a broad range of patients undergoing PCI, many patients currently do not receive such therapy because of concerns about bleeding complications or cost. Recently, bivalirudin with provisional GP IIb/IIIa inhibition has been validated as an alternative to heparin + routine GP IIb/IIIa inhibition for patients undergoing PCI. However, the cost-effectiveness of this novel strategy is unknown. METHODS: In the Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE)-2 trial, 4,651 U.S. patients undergoing non-emergent PCI were randomized to receive bivalirudin with provisional GP IIb/IIIa (n = 2,319) versus heparin + routine GP IIb/IIIa (n = 2,332). Resource utilization data were collected prospectively through 30-day follow-up on all U.S. patients. Medical care costs were estimated using standard methods including bottom-up accounting (for procedural costs), the Medicare fee schedule (for physician services), hospital billing data (for 2,821 of 4,862 admissions), and regression-based approaches for the remaining hospitalizations. RESULTS: Among the bivalirudin group, 7.7% required provisional GP IIb/IIIa. Thirty-day ischemic outcomes including death or myocardial infarction were similar for the bivalirudin and GP IIb/IIIa groups, but bivalirudin resulted in lower rates of major bleeding (2.8% vs. 4.5%, p = 0.002) and minor bleeding (15.1% vs. 28.1%, p < 0.001). Compared with routine GP IIb/IIIa, in-hospital and 30-day costs were reduced by $405 (95% confidence interval [CI] $37 to $773) and $374 (95% CI $61 to $688) per patient with bivalirudin (p < 0.001 for both). Regression modeling demonstrated that, in addition to the costs of the anticoagulants themselves, hospital savings were due primarily to reductions in major bleeding (cost savings = $107/patient), minor bleeding ($52/patient), and thrombocytopenia ($47/patient). CONCLUSIONS: Compared with heparin + routine GP IIb/IIIa inhibition, bivalirudin + provisional GP IIb/IIIa inhibition resulted in similar acute ischemic events and cost savings of $375 to $400/patient depending on the analytic perspective.     

A randomized two‐by‐two comparison of high‐dose bolus tirofiban versus abciximab and unfractionated heparin versus bivalirudin during percutaneous coronary revascularization and stent placement: The tirofiban evaluation of novel dosing versus abciximab with clopidogrel and inhibition of thrombin (TENACITY) study trial

Background : In the absence of high‐dose thienopyridines, placebo‐controlled trials have demonstrated a reduction in ischemic events with intravenous glycoprotein IIb/IIIa antagonists during percutaneous coronary intervention (PCI). One head‐to‐head trial comparing abciximab and tirofiban among PCI patients found tirofiban to be inferior, and laboratory evidence confirmed that the bolus dose of tirofiban tested in that trial to be less effective than abciximab. Whether a higher bolus dose of tirofiban would be as efficacious as abciximab during PCI is uncertain. Methods and Results : Patients undergoing PCI were randomized equally to abciximab or to tirofiban, given as high‐dose bolus (25 μg/kg) plus 12‐hr infusion (0.15 μg/kg/min). All patients received aspirin and clopidogrel and were additionally randomized to unfractionated heparin or bivalirudin. Approximately 8,000 patients were to be studied, but after 383 were enrolled, the study sponsor discontinued the trial for financial reasons. The primary endpoint of 30‐day death, myocardial infarction, or urgent target vessel revascularization occurred in 8.8% of patients randomized to abciximab and 6.9% of those randomized to tirofiban. The respective rates of major bleeding were 1.5 and 1.6%. Additionally, the primary endpoint occurred in 8.1% of patients randomized to unfractionated heparin and 7.6% of those randomized to bivalirudin. The respective rates of major bleeding were 2.5% and 0.5%. Conclusion : With limited assessment, this direct comparison of high‐dose bolus tirofiban versus abciximab produced encouraging results and suggests that further study of this tirofiban dose regimen is warranted. The limited assessments comparing heparin and bivalirudin are consistent with prior observations. © 2010 Wiley‐Liss, Inc.     

Bivalirudin with planned or provisional abciximab versus low-dose heparin and abciximab during percutaneous coronary revascularization: results of the Comparison of Abciximab Complications with Hirulog for Ischemic Events Trial (CACHET)

Background The direct thrombin inhibitor bivalirudin has previously been associated with better efficacy and lower hemorrhage risk than heparin during balloon angioplasty. This agent has not yet been tested with stenting or in combination with platelet glycoprotein IIb/IIIa antagonists. Methods and Results In a pilot trial, 268 patients who underwent coronary intervention were randomized in 3 sequential phases to treatment with bivalirudin (with or without abciximab) or the control regimen of low-dose weight-adjusted heparin with abciximab. Patients in the bivalirudin arms received bivalirudin (1.0 mg/kg bolus, infusion of 2.5 mg/kg/h for 4 hours) plus abciximab in phase A, bivalirudin (0.5 mg/kg bolus, infusion of 1.75 mg/kg/h for the procedure duration) plus provisional (“rescue”) abciximab in phase B, or bivalirudin (0.75 mg/kg bolus, infusion of 1.75 mg/kg/h for the procedure duration) plus provisional abciximab in phase C. Abciximab was necessitated on a provisional basis in 24% of the patients in the bivalirudin arms of phases B and C. A composite clinical endpoint of death, myocardial infarction, repeat revascularization, or major bleeding by 7 days occurred in 3.3%, 5.9%, 0, and 10.6% of the patients in the bivalirudin phase A, bivalirudin phase B, bivalirudin phase C, and heparin plus planned abciximab arms, respectively (P = .018 for the pooled bivalirudin groups versus the heparin group). Conclusion Bivalirudin with planned or provisional abciximab may be at least as safe and effective as low-dose heparin plus abciximab during percutaneous coronary intervention. (Am Heart J 2002;143:847-53.)     

Effect of anemia on hemorrhagic complications and mortality following percutaneous coronary intervention

The relation across anemia, hemorrhagic complications, and mortality associated with percutaneous coronary intervention (PCI) is unclear. We reviewed the Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE)-2 Trial, which compared bivalirudin plus provisional glycoprotein IIb/IIIa blockade with heparin plus planned glycoprotein IIb/IIIa blockade in patients undergoing urgent or elective PCI. Of the 6,010 patients randomized in REPLACE-2, 1,371 (23%) were anemic. Major bleeding was more common in anemic than in nonanemic patients (4.9% vs 2.8%, p = 0.0001). In anemic patients, treatment with bivalirudin (n = 678) resulted in a lower risk of major bleeding versus heparin plus glycoprotein IIb/IIIa blockade (n = 693, 3.5% vs 6.2%, p = 0.0221). Mortality was higher in anemic patients than in nonanemic patients at 30 days (0.9% vs 0.2%, p <0.0001), 6 months (2.6% vs 0.7%, p <0.0001), and 1 year (4.3% vs 1.5%, p <0.0001). There were no differences between anemic and nonanemic patients with regard to ischemic complications at 30 days. Although anemic patients had higher mortality rates, proportions of cardiovascular and noncardiovascular mortalities were equal in anemic and nonanemic patients. In conclusion, anemic patients undergoing PCI have an increased risk of mortality and major bleeding, but not of ischemic events, and the use of bivalirudin with provisional glycoprotein IIb/IIIa blockade decreases the risk of hemorrhagic complications compared with heparin plus planned glycoprotein IIb/IIIa blockade.     

Association of prerandomization anticoagulant switching with bleeding in the setting of percutaneous coronary intervention (A REPLACE-2 analysis)

The REPLACE-2 trial of patients who underwent urgent or elective percutaneous coronary intervention (PCI) demonstrated a significantly lower bleeding risk with bivalirudin plus provisional glycoprotein IIb/IIIa inhibitor compared with unfractionated heparin with planned glycoprotein IIb/IIIa inhibitor. The goal of this analysis was to evaluate whether a hazard existed when unfractionated heparin or low-molecular-weight heparin was administered before study medication in the REPLACE-2 trial. The REPLACE-2 trial randomized 6,010 patients undergoing PCI to receive bivalirudin plus provisional glycoprotein IIb/IIIa inhibitor or unfractionated heparin plus planned glycoprotein IIb/IIIa inhibitor. The present study compared bleeding among patients treated with or without antithrombin therapy in the 48 hours before study treatment. Among patients treated with bivalirudin, there was no difference in protocol-defined major or minor bleeding, bleeding according to Thrombolysis In Myocardial Infarction criteria, or noncoronary artery bypass graft blood transfusions between the patients treated with versus without antithrombin therapy (p=NS). However, in patients treated with unfractionated heparin plus planned glycoprotein IIb/IIIa inhibitor, there was a significant increase in the composite of protocol-defined major or minor bleeding and in noncoronary artery bypass graft blood transfusions (p<0.05 for 3-way comparison vs no unfractionated heparin and for 2-way comparisons of no unfractionated heparin vs unfractionated heparin or low-molecular-weight heparin). In conclusion, in patients treated with bivalirudin, pretreatment with antithrombin therapy was not associated with increased bleeding. In contrast, among patients randomized to receive unfractionated heparin and planned glycoprotein IIb/IIIa, pretreatment with antithrombin therapy was associated with increased protocol-defined composite major or minor bleeding and increased need for transfusion.     

Triple antiplatelet therapy during percutaneous coronary intervention is associated with improved outcomes including one-year survival: results from the Do Tirofiban and ReoProGive Similar Efficacy Outcome Trial (TARGET)

OBJECTIVE: We sought to examine if clopidogrel treatment initiated before coronary stenting improved clinical outcomes among patients receiving aspirin and a glycoprotein (GP) IIb/IIIa inhibitor. BACKGROUND: Antiplatelet therapy plays a pivotal role in contemporary percutaneous coronary interventions (PCI). METHODS: Outcomes among 4,809 patients randomized to tirofiban or abciximab during PCI with stent placement were compared according to whether they received 300 mg of clopidogrel before PCI (93.1%) versus immediately after the procedure. RESULTS: The 30-day primary composite end point (death, myocardial infarction [MI], or urgent target vessel revascularization [TVR]) was lower among clopidogrel-pretreated patients (6.6% vs. 10.4%, p = 0.009), mainly because of reduction of MI (6.0% vs. 9.5%, p = 0.012). The benefit of clopidogrel pretreatment was sustained at six months (death, MI, any TVR: 14.6% vs. 19.8%, HR = 0.71, p = 0.010), and this was due mainly to lowering of death and MI (7.8% vs. 13.0%, p = 0.001). At one year, clopidogrel pretreatment was associated with a lower mortality rate (1.7% vs. 3.6%, p = 0.011). Because clopidogrel pretreatment was not randomized, multivariable and propensity analyses were performed. After adjusting for baseline heterogeneity, clopidogrel pretreatment was an independent predictor for death or MI at 30 days (HR = 0.63, p = 0.012) and at six months (HR = 0.61, p = 0.003), and survival at one year (HR = 0.53, p = 0.044). No excess in 30-day bleeding events was noted with clopidogrel pretreatment. CONCLUSIONS: Among patients undergoing coronary stent placement with aspirin and a GP IIb/IIIa inhibitor, clopidogrel pretreatment is associated with a reduction of death and MI irrespective of the type of GP IIb/IIIa inhibitor used.     

Comparison of safety and efficacy of bivalirudin versus unfractionated heparin in high-risk patients undergoing percutaneous coronary intervention (from the Anti-Thrombotic Strategy for Reduction of Myocardial Damage During Angioplasty-Bivalirudin vs Heparin study)

Bivalirudin, a direct thrombin inhibitor, is as effective as unfractionated heparin (UFH), with decreased bleeding in patients with acute coronary syndromes who undergo percutaneous coronary intervention (PCI). The aim of this study was to evaluate the effectiveness of bivalirudin versus UFH in selected PCI patients at high bleeding risk. Four hundred one consecutive patients who underwent PCI fulfilling ≥ 1 enrollment criterion (age >75 years, chronic renal failure, and diabetes mellitus) were randomized to bivalirudin (bolus 0.75 mg/kg followed by infusion during the procedure; n = 198) or UFH (75 IU/kg; n = 203). In the overall population, 39% were aged >75 years, 22% had renal failure, 63% had diabetes, and 29% had acute coronary syndromes. The primary efficacy end point was the 30-day incidence of major adverse cardiac events (cardiac death, myocardial infarction, stent thrombosis, or target vessel revascularization). The primary safety end point was the occurrence of any bleeding or entry-site complications after PCI. All patients were preloaded with clopidogrel 600 mg. Glycoprotein IIb/IIIa inhibitors were used at the operators' discretion. Thirty-day major adverse cardiac event rates were 11.1% in the bivalirudin group and 8.9% in the UFH group (p = 0.56); the primary efficacy end point was reached mainly because of periprocedural myocardial infarction; 1 patient in the bivalirudin group had stent thrombosis. Occurrence of the primary safety end point was 1.5% in the bivalirudin group and 9.9% in the UFH group (p = 0.0001); this benefit was essentially driven by the prevention of entry-site hematomas >10 cm (0.5% vs 6.9%, p = 0.002). In conclusion, Anti-Thrombotic Strategy for Reduction of Myocardial Damage During Angioplasty-Bivalirudin vs Heparin (ARMYDA-7 BIVALVE) indicates that bivalirudin, compared with UFH, causes significantly lower bleeding and has a similar incidence of major adverse cardiac events in patients with older age, diabetes mellitus, or chronic renal failure who undergo PCI.     

Outcomes of Patients with Coronary Artery Perforation Complicating Percutaneous Coronary Intervention and Correlations with the Type of Adjunctive Antithrombotic Therapy: Pooled Analysis from REPLACE-2, ACUITY, and HORIZONS-AMI Trials

Background: The lack of a specific counteragent to bivalirudin may complicate the management of patients with coronary artery (CA) perforation during percutaneous coronary intervention (PCI).
Aim: Assess outcomes of patients with CA perforation from three PCI trials comparing intravenous bivalirudin with provisional glycoprotein (GP) IIb/IIIa inhibition versus unfractionated heparin (UFH) plus GP IIb/IIIa.
Methods: A pooled analysis of patients treated with PCI in three randomized trials including REPLACE-2, ACUITY, and HORIZONS-AMI.
Results: Among a total of 12,921 patients, CA perforation occurred in 35 patients (0.27%). By multivariable analysis, baseline creatinine clearance was the only independent predictor of CA perforation (per 10 mL/min decrease, odds ratio [95% confidence interval]= 1.28 [1.11, 1.47], P = 0.0007). At 30 days, patients with versus without CA perforation had significantly (all P values ≤0.001) higher rates of 30-day mortality (11.4% vs. 1.0%), myocardial infarction (MI) [Q wave: 22.9% vs. 5.7%; non-Q wave: 17.1% vs. 4.9%], target vessel revascularization (TVR) [20.1% vs. 1.8%], and composite end-point of death/MI/TVR (31.4% vs. 7.8%). Patients assigned to bivalirudin versus UFH plus a GP IIb/IIIa inhibitor had nonsignificantly lower rates of death (0% vs. 18.8%, P = 0.08), similar rates of MI (26.7% vs. 25.0%, P = 0.92), significantly lower rates of TVR (6.7% vs. 37.5%, P = 0.04), and similar rates of the composite end-point of death/MI/TVR (35.5% vs. 26.7%, P = 0.54).
Conclusion: In three PCI trials, treatment of patients experiencing CA perforation with adjunctive antithrombotic therapy of bivalirudin monotherapy was not associated with worse outcomes compared to treatment with UFH plus GP IIb/IIIa inhibitors.     

Platelet glycoprotein IIb/IIIa inhibitors

Glycoprotein (GP) IIb/IIIa inhibitors including abciximab, eptifibatide and tirofiban have been studied extensively as short-term adjuncts to short-term heparin and indefinite aspirin in patients with acute coronary syndrome or undergoing percutaneous coronary interventions on native vessels. The drugs provide a small advantage in the composite endpoint of death, myocardial infarction, and need for revascularization at 30 days (1-2% of treated patients) at the expense of an increase in major and potentially fatal bleeding complications (1% of treated patients over heparin plus aspirin alone). Highest-risk patients appear to benefit the most; clopidogrel should also be considered in these patients. Patients undergoing percutaneous interventions on bypass grafts do not benefit. Whether one GP IIb/IIIa inhibitor is superior to another is incompletely clarified. Abciximab causes severe immune-mediated thrombocytopenia (<20,000/microl) in 0.7% of cases; this is more often than eptifibatide or tirofiban (0.2%). Pseudothrombocytopenia should be differentiated. Effective use of GP IIb/IIIa inhibitors for acute coronary syndrome and percutaneous coronary interventions requires discerning clinical judgment. The value of GP IIb/IIIa inhibitors is not established in other forms of vascular disease.     

What anti‐thrombotic therapy is best with primary PCI for acute ST elevation myocardial infarction: How should the HORIZONS trial change current practice?

The current standard of care for anti‐thrombotic therapy with primary PCI for acute ST elevation myocardial infarction (STEMI) is aspirin, clopidogrel, unfractionated heparin and platelet glycoprotein IIb/IIIa inhibitors. However, heparin and glycoprotein IIb/IIIa inhibitors are associated with a high incidence of bleeding, and many of the trials documenting benefit with this therapy were performed before the widespread use of stents and clopidogrel. Bivalirudin is a direct thrombin inhibitor which has been found to have similar efficacy with less bleeding compared with heparin plus glycoprotein IIb/IIIa inhibitors when used with elective PCI and with PCI for unstable angina and non‐ST elevation myocardial infarction. The HORIZONS trial evaluated bivalirudin compared with unfractionated heparin and IIb/IIIa inhibitors in patients with STEMI treated with primary PCI and found similar MACE (major adverse cardiac events) with less bleeding and a lower incidence of net adverse clinical events (MACE or major bleeding) at 30 days. Mortality at 30 days was also significantly less with bivalirudin. These results make a strong case for the use of bivalirudin with primary PCI in the great majority of patients with STEMI, with the possible exception of patients with cardiogenic shock or stent thrombosis, and patients with a large thrombus burden or no re‐flow following PCI. In the latter case, platelet glycoprotein IIb/IIIa inhibitors would be used as a bail‐out strategy. © 2008 Wiley‐Liss, Inc.