A propensity analysis of the impact of platelet glycoprotein IIb/IIIa inhibitor therapy on in-hospital outcomes after percutaneous coronary intervention

It is unknown whether the benefits of parenteral platelet glycoprotein (GP) IIb/IIIa inhibitors as an adjunct to percutaneous coronary intervention (PCI) demonstrated in randomized clinical trials extend to patients treated outside the setting of clinical trials. A contemporary registry of 10,847 consecutive PCI procedures was analyzed to determine the effect of GP IIb/IIIa inhibitor treatment on in-hospital major adverse coronary events ([MACEs] composite of death, urgent coronary artery bypass surgery, periprocedural myocardial infarction, abrupt closure, and stent thrombosis). In this registry, GP IIb/IIIa inhibitors were administered to 20.1% of patients. These patients were younger, more often men, and less often hypertensive than untreated patients. GP IIb/IIIa inhibitor-treated patients were more likely to present with acute myocardial infarction or unstable angina. Stents were placed in 79% of patients treated with GP IIb/IIIa inhibitors. MACEs occurred in 7.8% of GP IIb/IIIa inhibitor-treated patients compared with 3.8% of untreated patients (p <0.001). After multivariable adjustment for the propensity of GP IIb/IIIa inhibitor treatment as well as other possible confounders and interactions known to influence MACEs, GP IIb/IIIa inhibitor treatment was associated with a 57% increase in the risk of a MACE (odds ratio 1.57, 95% confidence interval 1.22 to 2.03; p = 0.0004). In a data set consisting of patients with a high degree of acuity predominantly treated with stent placement, GP IIb/IIIa inhibitor treatment is associated with an increase in thrombotic complications of PCI.     

A Practical Approach to the Diagnosis and Management of Thrombocytopenia Associated with Glycoprotein IIb/IIIa Receptor Inhibitors

The introduction of drugs that inhibit the GP IIb/IIIa receptor represents one of the most important new developments in the field of cardiovascular pharmacotherapeutics of the past decade. Thrombocytopenia associated with a GP IIb/IIIa inhibitor can occur in up to 5% of patients and is associated with poor clinical outcomes. Monitoring of the platelet count early after administration of these drugs is recommended and further assessment of the platelet count should be performed with long-term oral administration. Confirmation of true thrombocytopenia and an investigation of other potential etiologies are crucial initial diagnostic steps that should be taken when a platelet count of <100,000/cm³ is encountered. In patients receiving concomitant heparin, identification of heparin-induced thrombocytopenia using an enzyme-linked immunosorbent assay to detect anti-heparin-PF4 antibodies is preferred. Treatment recommendations depend upon the severity of thrombocytopenia and presence of bleeding. In general, GP IIb/IIIa inhibitor therapy should be stopped; conventional critical care instituted; and platelet transfusions considered if the platelet count is <10,000/cm³, if there is severe bleeding, or if an emergency invasive procedure is required. Readministration of GP IIb/IIIa inhibitors may be associated with an increased risk of thrombocytopenia in selected circumstances, and caution is advised if the patient had previously experienced a significant decline in the platelet count or developed drug-induced antibodies following prior use. Future areas of research should target the mechanism(s) of thrombocytopenia, more accurate diagnostic methods, and the risk of thrombocytopenia when these drugs are combined with other antiplatelet and anticoagulant agents.     

Profound thrombocytopenia associated with tirofiban: case report and review of literature

Platelet glycoprotein (GP)IIb/IIIa inhibitors prevent fibrinogen binding and platelet aggregation. Inhibition of platelet activity at the injured coronary plaque is a target for novel therapeutic strategies. They decrease ischemic complications associated with non-ST-segment elevation acute coronary syndromes and percutaneous coronary intervention. Thrombocytopenia is a serious complication well described with the use of the prototype GP IIb/IIIa inhibitor abciximab. Its association with other agents of this class has been underemphasized. It is important to monitor platelet counts closely after initiation of GP IIb/IIIa inhibitor therapy, not only for abciximab, but also for small molecule inhibitors such as eptifibatide and tirofiban. Monitoring of platelet counts at 2 to 6 hours and 24 hours will detect most cases of acute thrombocytopenia. Adverse events may be prevented by prompt discontinuation of GP IIb/IIIa inhibitor therapy. The authors present a case of profound thrombocytopenia after the administration of tirofiban in the treatment of a patient with an acute coronary syndrome.     

Synthetic inhibitors of platelet glycoprotein IIb/IIIa in clinical development

Activation of the platelet glycoprotein (GP IIb/IIIa) receptor on the platelet surface is the final pathway of platelet aggregation, regardless of the initiating stimulus. Inhibitors of GP IIb/IIIa receptors include monoclonal antibodies (abciximab) against this receptor and peptidic and nonpeptidic synthetic specific receptor blockers. Abciximab exchanges between and binds to platelets for as long as 2 weeks, whereas synthetic GP IIb/IIIa inhibitors inhibit ex vivo platelet aggregation for only a few hours after the end of infusion, but some have the advantage of also being orally active. In the secondary prevention of atherothrombosis, large-scale trials were successfully conducted with aspirin, dipyridamole, ticlopidine, and clopidogrel. In the first large-scale trials with GP IIb/IIIa inhibitors, abciximab was investigated. In aggregate, synthetic GP IIb/IIIa inhibitors, combined with aspirin and heparin, were shown to reduce ischemic events in patients with high- and low-risk coronary intervention, stents, unstable angina, and non-Q-wave infarction. With short-term use of synthetic GP IIb/IIIa inhibitors, there is no suppression of clinical evident restenosis 6 months after the end of treatment. With the doses currently used, bleeding occurs more often with the synthetic GP IIb/IIIa inhibitors (used for 3 days) than with abciximab (used for 12 hours), but there are no direct comparisons between these drugs.     

Hemostatic gene polymorphisms and the prevalence of thrombotic complications in polycythemia vera and essential thrombocythemia.

Patients with polycythemia vera and essential thrombocythemia are at risk for thrombotic and bleeding complications. Currently, no diagnostic test can predict thrombohemorrhagic complications. In a prospective study of 86 patients with polycythemia vera (43 patients) or essential thrombocythemia (43 patients), we examined the possible role of polymorphisms of platelet adhesion receptors [glycoprotein (GP) Ibalpha, GPIa, GPIIIa) and clotting factor II (prothrombin's G20210A mutation) and clotting factor V (Leiden mutation) in determining the risk of thrombotic or bleeding complications. Except for an association between vasomotor symptoms and prothrombin mutation (P < 0.001), no significant correlation between polymorphism of clotting factors and thrombohemorrhagic complications was identified. When the entire patient cohort was considered, the polymorphisms of platelet adhesion receptors were not associated with the risk for thrombotic or bleeding complications. However, among patients with polycythemia vera, the presence of the PlA2 allele of GPIIIa was associated with an increased risk of arterial thrombosis. In view of previous studies linking the presence of the PlA2 allele of GPIIIa to a higher risk for coronary artery thrombosis, our data have physiologic relevance. However, they need to be confirmed in a larger study.     

Bleeding risk of platelet glycoprotein IIb/IIIa receptor antagonists in broad-based practice (results from the Society for Cardiac Angiography and Interventions Registry)

Randomized trials of platelet glycoprotein (GP) IIb/IIIa receptor inhibitors in patients who have undergone percutaneous coronary intervention (PCI) have shown a modest increase in bleeding risk associated with GP IIb/IIIa inhibitor use. Because clinical trials often enroll highly selected patient populations and are performed in high-volume experienced centers, these results may not apply to a nonclinical trial population, thus altering the risk-benefit ratio of the drugs. Given the widespread use of these agents, we sought to determine bleeding risks in a broad-based population of patients who underwent PCI. We performed a retrospective cohort study of GP IIb/IIIa inhibitors and bleeding in 18,821 procedures from June 1, 1996 to December 31, 1998 using the Society for Cardiac Angiography and Interventions Registry. The primary outcome was bleeding events, defined as clinically significant hematoma formation or hemorrhage. Bleeding risk was 1.9% in the 2,525 patients who received GP IIb/IIIa inhibitors compared with 1.0% in the 16,296 who did not (unadjusted odds ratio [OR] 1.87, 95% confidence interval [CI] 1.35 to 2.59, p <0.001). After adjustment for multiple clinical and procedural variables, the effect was attenuated, with at most a twofold bleeding risk associated with GP IIb/IIIa inhibitor use (adjusted OR 1.39, 95% CI 0.96 to 2.03, p = 0.083). The small increase in absolute risk of bleeding from GP IIb/IIIa inhibitor use in this study is similar to the risk observed in clinical trials. Assuming these agents are as effective as shown in these trials, the risk-benefit ratio of GP IIb/IIIa inhibitors in broad-based PCI practice should be favorable.     

Antiplatelet Strategies: Evaluating Their Current Role in the Setting of Acute Coronary Syndromes

Numerous clinical trials have established the value of antiplatelet therapies for acute coronary syndromes (ACS). Aspirin (ASA), thienopyridines (i.e., clopidogrel and ticlopidine) and GP IIb/IIIa antagonists comprise the major classes of antiplatelet therapies demonstrated to be of benefit in the treatment of ACS and for the prevention of thrombotic complications of percutaneous coronary intervention (PCI). Clopidogrel is beneficial when administered before and after PCI, and is more effective when combined with either ASA or GP IIb/IIIa inhibitors in preventing post‐PCI complications, coronary subacute stent thrombosis, and thrombotic events in general. It is currently unclear whether a higher loading dose of clopidogrel (600 mg) is better than the standard loading dose (300 mg), how long therapy should continue, and which maintenance dose is optimal. The role of the GP IIb/IIIa antagonists in ACS is less clear due to conflicting data from several studies with different patient populations. Currently, it appears that the use of GP IIb/IIIa antagonists might be most beneficial in high‐risk ACS patients scheduled to undergo PCI, who demonstrate non‐ST‐segment elevation myocardial infarction and elevated troponin levels. Copyright © 2008 Wiley Periodicals, Inc.     

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.     

Emergency coronary artery bypass grafting in patients with acute myocardial infarction treated with glycoprotein IIb/IIIa receptor inhibitors

Glycoprotein (GP) IIb/IIIa receptor inhibitors before primary angioplasty in patients with ST-elevation acute myocardial infarction (STEMI) are recommended by current guidelines. Thus, an increasing number of patients receive these drugs before coronary angiography, particularly if a between-hospital transfer is needed. However, when coronary anatomy is unsuitable for angioplasty, emergency coronary artery bypass grafting (CABG) under GP IIb/IIIa inhibitor treatment may be needed, with a potential increase in bleeding risk. Abciximab has a long duration of action, because of its high-affinity binding to GP IIb/IIIa receptors. Initial retrospective studies reported a higher incidence of major bleeding during emergency CABG after abciximab administration, leading to the recommendation of delaying surgery >12 h. However, data from the prospective trials on abciximab do not confirm the increase in bleeding risk, and current evidence shows that emergency surgery can be performed safely soon after abciximab cessation. Monitoring of activated clotting time during surgery and platelet transfusion in case of postoperative relevant bleeding are the only measures needed. No data are available on emergency surgery in patients with STEMI treated with eptifibatide or tirofiban. However, their short-lasting effects and the results of trials on non-ST-elevation acute coronary syndromes suggest that they could even reduce postoperative bleeding by preventing platelet consumption during cardiopulmonary bypass. In conclusion, the early administration of GP IIb/IIIa inhibitors, in particular of abciximab, in patients with STEMI in whom primary angioplasty is planned should not be discouraged because of the potential bleeding risk in case of emergency CABG.     

Acute profound thrombocytopenia after abciximab therapy during coronary angioplasty

Since the extensive use of abciximab, a potent antiplatelet agent directed against GP IIb/IIIa platelet receptors, to prevent ischemic complications of percutaneous transluminal coronary angioplasty, few cases of thrombocytopenia have been observed. This paper reports a case of acute profound thrombocytopenia (platelet count: 800/mm3) occurring 16 h after abciximab therapy during coronary angioplasty. As thrombocytopenia occurrence is not predictable, platelet count should be evaluated periodically after drug administration. Mechanisms of this adverse effect remain unknown. Platelet transfusion results in a rapid and sustained improvement of platelet count, avoiding the occurrence of major hemorrhagic complications.     

Safety of glycoprotein IIb/IIIa inhibitors in urgent or emergency coronary artery bypass graft surgery

Approximately 2% to 4% of patients undergo urgent or emergency coronary artery bypass grafting (CABG) for complications of percutaneous coronary intervention (PCI) after treatment with glycoprotein (GP) IIb/IIIa inhibitors. The pharmacokinetic and pharmacodynamic properties of GP IIb/IIIa inhibitors play a large role in determining the safety of their use in the setting of urgent or emergency CABG procedures. Emergency or urgent CABG after treatment with the GP IIb/IIIa inhibitor, abciximab, may be associated with increased risk of hemorrhage and the requirement of platelet transfusions if surgery is performed within 12 h of abciximab discontinuation. Eptifibatide is associated with a similar risk compared with placebo, even when surgery is performed within 2 h of eptifibatide cessation. Limited data for tirofiban show that bleeding is not increased when compared with acetylsalicylic acid or heparin. Eptifibatide and tirofiban appear to have favourable safety profiles compared with abciximab in the setting of emergency or urgent CABG after failed PCI.     

Thrombocytopenia complicating treatment with intravenous glycoprotein IIb/IIIa receptor inhibitors: a pooled analysis

BACKGROUND: Despite the increasingly prevalent role of platelet glycoprotein (GP) IIb/IIIa receptor inhibitors in acute coronary syndromes and percutaneous coronary interventions, the incidence and clinical relevance of thrombocytopenia occurring with their use remain unclear. METHODS: We identified 8 placebo-controlled, randomized, large trials of GP IIb/IIIa receptor inhibitors reporting the incidence of thrombocytopenia, grouped by severity. The clinical courses of 42 patients with GP IIb/IIIa-related thrombocytopenia in these studies and other case reports were reviewed for bleeding complications. RESULTS: Abciximab increased mild thrombocytopenia compared with placebo (4.2% vs 2.0%; P <.001; odds ratio 2.14) and increased severe thrombocytopenia compared with placebo (1.0% vs 0.4%; P =.01; odds ratio 2.48). Small-molecule IIb/IIIa inhibitors did not significantly increase mild or severe thrombocytopenia compared with placebo. Mild thrombocytopenia occurred more frequently in acute coronary syndrome trials than in coronary intervention trials, even in patients not receiving any IIb/IIIa inhibitors. No major bleeding sequelae were reported in 23 patients with severe thrombocytopenia or in 19 patients with profound thrombocytopenia. CONCLUSIONS: Abciximab, but not eptifibatide or tirofiban, increases the incidence of thrombocytopenia compared with placebo in patients also treated with heparin. Thrombocytopenia associated with GP IIb/IIIa inhibition does not routinely lead to severe bleeding complications.     

Use of Glycoprotein IIb/IIIa Inhibition Plus Fibrinolysis in Acute Myocardial Infarction

Pharmacological reperfusion therapy for acute myocardial infarction with intravenous fibrinolytic agents improves survival yet fails to achieve early and complete coronary blood flow in nearly half of treated patients. In principle, glycoprotein (GP) IIb/IIIa inhibitors, potent antiplatelet agents, might improve the efficacy and clinical outcomes associated with fibrinolysis. Preclinical research suggests more rapid and effective reperfusion with combined platelet GP IIb/IIIa inhibition and fibrinolysis. Early clinical studies confirm improved early patency and more rapid electrocardiographic resolution, but increased bleeding complications, with the addition of GP IIb/IIIa antagonists to conventional fibrinolysis. Future studies may combine reduced-dose fibrinolytic therapy with GP IIb/IIIa inhibition to optimize efficacy and safety.     

Platelet Glycoprotein IIb/IIIa Integrin Blockade in Coronary Artery Disease: Current State of the Art

Platelets have been shown to play an important role in the pathogenesis of atherosclerosis, acute coronary syndromes, and ischemic complications after percutaneous coronary intervention. Fibrinogen binding via platelet surface glycoprotein (GP) IIb/IIIa receptors constitutes the "final pathway" in platelet aggregation leading to thrombus formation. The GP IIb/IIIa receptor inhibitors, a new class of antiplatelet agents that have emerged in recent years, show great promise in reducing complications of coronary angioplasty and acute coronary syndromes. This review will examine the biology of platelet GP IIb/IIIa receptors, the various classes of GP IIb/IIIa receptor antagonists, the results of the latest clinical trials, and their implications in current clinical practice.     

Abciximab-induced alveolar hemorrhage after percutaneous coronary intervention

Abciximab, a platelet glycoprotein (GP) IIb/IIIa inhibitor, has been shown to improve clinical outcomes in patients undergoing percutaneous coronary intervention. However, there is a well-documented increase in bleeding risk associated with the use of this agent. Spontaneous pulmonary hemorrhage is a particularly rare and easily misdiagnosed complication that requires early diagnosis to ensure patient survival. A 61-year-old man presented to the emergency department with chest pain and inferolateral ST elevation on electrocardiogram. A paclitaxel drug-eluting stent was then placed in the left circumflex artery, without complications. Abciximab (a bolus of 0.25 mg/kg followed by an infusion of 10 mg/min for 12 h) was given. Approximately 20 min later, the patient developed dyspnea and hemoptysis. A chest radiograph revealed new bilateral diffuse interstitial infiltrates, and the patient was started on empirical antibiotics for pneumonia. Because of increasing dyspnea and somnolence, the patient was intubated and bronchoscopy was performed, revealing serial hemorrhagic returns from the left lower lobe, diagnostic of diffuse alveolar hemorrhage and judged to be secondary to abciximab, given the time course. All antiplatelet and antithrombotic agents were stopped. The patient stabilized over the next several days, with some recurrent hemoptysis, and was successfully extubated seven days later. Prognosis remains poor in GP IIb/IIIa inhibitor-induced pulmonary hemorrhage, and early diagnosis is critical so that antithrombotic and antiplatelet agents may be discontinued in a timely manner. A high degree of suspicion is required when treating a patient who presents with dyspnea and new radiological infiltrates after receiving a GP IIb/IIIa inhibitor.     

Acquired Glanzmann's thrombasthenia without thrombocytopenia: a severe acquired autoimmune bleeding disorder

Acquired Glanzmann's thrombasthenia (GT) is an uncommon accompaniment to immune thrombocytopenic purpura. Rarely, GT may present as an acquired autoimmune disorder of platelet function, with rapid onset of a moderate-to-severe bleeding tendency, a prolonged bleeding time, but with a normal platelet count and normal platelet glycoprotein (GP) expression. This is caused by an autoantibody with specificity for platelet GP IIb/IIIa or an epitope close to that of the GP, resulting in partial or complete refractoriness of the patient's platelets to ADP, collagen and arachidonic acid. We describe two patients with acquired GT and a normal platelet count, who presented with severe bleeding. The first patient responded gradually to immunosuppressive treatment but eventually developed non-Hodgkin's lymphoma. The second patient had no other underlying conditions and remitted spontaneously within 2 years.     

Successful use of glycoprotein IIb/IIIa inhibitor, heparin, and IABP during PCI in a post-neurosurgical patient with STEMI and cardiogenic shock due to very late bare-metal stent thrombosis

Stent thrombosis is not unusual in a post-operative setting. Use of heparin, aspirin, clopidogrel, and glycoprotein (GP) IIb/IIIa inhibitors in this setting needs to be balanced because of the increased risk of perioperative bleeding. This is of special concern in neurosurgery, where postoperative mass effect from bleeding in a closed space is a serious risk. We describe a unique case of inferior and anterior ST-elevation myocardial infarction in cardiogenic shock during spinal surgery with acute, very late bare-metal stent (BMS) thrombosis in the left anterior descending coronary artery and simultaneous acute thrombotic occlusion of the right coronary artery, treated by primary percutaneous intervention, intra-aortic balloon pump (IABP) support and use of GP IIb/IIIa inhibitor in addition to clopidogrel, aspirin, and heparin with good surgical and cardiac outcome. This case report describes first time use of GP IIb/IIIa inhibitor and IABP with heparin, in a patient just after spinal surgery.     

Complementary effects of thienopyridine pretreatment and platelet glycoprotein IIb/IIIa integrin blockade with eptifibatide in coronary stent intervention; results from the ESPRIT trial.

OBJECTIVES: This analysis sought to investigate the complementary effect of thienopyridine pretreatment and platelet glycoprotein (GP) IIb/IIIa integrin blockade in coronary stent intervention. BACKGROUND: Definitive evidence supporting combined antiplatelet therapy consisting of thienopyridine pretreatment and GP IIb/IIIa receptor blockade in patients undergoing percutaneous coronary intervention (PCI) with stent implantation is limited. METHODS: We retrospectively analyzed clinical outcomes by thienopyridine use in the 2,040 patients randomized to eptifibatide or placebo who underwent PCI in the ESPRIT trial. RESULTS: A total of 901 patients received a loading dose of thienopyridine before PCI (group 1), 123 received thienopyridine pretreatment without a loading dose (group 2), and 1,016 were not treated with thienopyridine before PCI (group 3). The composite incidence of death or myocardial infarction at 30 days was significantly lower in group 1 than in groups 2 and 3 combined (OR, 0.71 [95%CI, 0.52-0.99]; P = 0.0417). A similar trend was seen for the composite of death, myocardial infarction, or urgent target vessel revascularization (unadjusted OR, 0.77 [0.57-1.05]; P = 0.1025). After adjusting for baseline characteristics, these differences were no longer significant. No interactions were identified with eptifibatide assignment for any of the group comparisons. CONCLUSIONS: Pretreatment with a loading dose of thienopyridine lowers the rate of ischemic complications regardless of treatment with a GP IIb/IIIa inhibitor. Conversely, the efficacy of eptifibatide is maintained whether or not a loading dose of a thienopyridine is administered. Optimal outcomes are achieved in patients receiving thienopyridine pretreatment along with platelet GP IIb/IIIa inhibitor therapy.     

Bridging with glycoprotein IIb/IIIa inhibitors for periprocedural management of antiplatelet therapy in patients with drug eluting stents

Objective : To describe outcomes when glycoprotein IIb/IIIa (GP IIb/IIIa) inhibitors are used as bridging antiplatelet therapy for surgical procedures in patients with drug eluting stents (DES). Background : The optimal management of patients with DES who require surgical procedures prior to completion of antiplatelet therapy is unclear. In high risk patients, the use of GP IIb/IIIa inhibitors as bridging therapy while antiplatelet therapy is held has been described, but safety and efficacy data remain sparse. Methods : A pharmacy database was used to identify GP IIb/IIIa inhibitor orders at our hospital between January 1, 2007 and July 31, 2009. Indication for GP IIb/IIIa inhibitor administration and other clinical data were gathered through retrospective review of medical records. End points assessed were stent thrombosis, major bleeding, minor bleeding, postoperative acute coronary syndrome, and death within 30 days. Results : Four thousand One hundred seventy‐six separate orders for GP IIb/IIIa inhibitors were identified (January 1, 2007 to July 31, 2009). Six patients underwent non‐cardiac and thirteen underwent cardiac surgery. Clopidogrel was discontinued a median of 6 days before surgery and 2 days prior to initiating GP IIb/IIIa inhibitor. All bridging patients were treated with eptifibatide infusion prior to procedure. There were no stent thromboses, deaths, or acute coronary syndrome events. Major bleeding occurred in 7 (53.9%) cardiac surgery patients and none of the non‐cardiac surgery patients, while minor bleeding occurred in 1 (7.7%) and 1 (16.6%) patients, respectively. Conclusions : In patients with DES, who require cessation of clopidogrel before surgery, bridging with GP IIb/IIIa inhibitors appears effective in preventing adverse cardiac outcomes but may be associated with bleeding in patients undergoing cardiac surgery. © 2011 Wiley Periodicals, Inc.     

An audit of the use and complications of glycoprotein IIb/IIIa inhibitors in percutaneous coronary intervention against national UK standards

Coronary thrombosis is a pivotal event in the pathogenesis of acute coronary syndromes and ischemic complications resulting from coronary intervention. Activation of the platelet glycoprotein (GP) IIb/IIIa receptor is the final common pathway leading to platelet aggregation, coronary thrombus formation, and myocardial ischemia. Inhibitors of platelet GP IIb/IIIa are potent agents to prevent progression to myocardial infarction and death.

We prospectively surveyed the indications, frequency, and complications associated with the use of GP IIb/IIIa inhibitors in percutaneous coronary intervention in a tertiary center setting.

A total of 170 patients underwent screening over a period of 6 weeks. One hundred four (61%) had coronary intervention, out of which eight (8%) had failed intervention. Glycoprotein IIb/IIIa inhibitors were used in 57 (55%) patients; 47 (45%) did not have any agent periprocedure. Eptifibatide was the most commonly used agent in 35 (33%), followed by abciximab in 19 (18%) and tirofiban in 3 (3%).

Out of 57 patients in whom GP IIb/IIIa agents were used, 22 (38%) had visible intracoronary thrombus, 22 (38%) had diffuse disease, 8 (14%) had complex intervention, and 5 (9%) had diabetes.

The overall incidence of complications was not increased by the use of GP IIb/IIIa inhibitors; serious complications were rare with the use of GP IIb/IIIa agents; no stroke, thrombocytopenia, gastrointestinal bleed, or death was recorded. The overall use in emergency settings was not associated with increased complications. Bradycardia and vomiting were more common with abciximab group, whereas puncture site pain was commoner in eptifibatide group.