Glycoprotein IIb/IIIa Inhibitors Therapy Research Articles

Use of Glycoprotein IIb-IIIa Inhibitors in Patients Undergoing Carotid Artery Stenting in the Vascular Quality Initiative

Antiplatelet therapies with thromboxane inhibitors and adenosine 5'-diphosphate antagonists have been widely used following carotid artery stenting (CAS). However, these therapies may not apply to patients who are intolerant or present acutely. Glycoprotein IIb/IIIa inhibitors (GPI) are a proposed alternative therapy in these patients; however, their use has been limited due to concerns of increased risk for intracranial bleeding. Thus, this study aims to assess the safety profile of GPI in patients undergoing CAS. All patients undergoing CAS in the Society of Vascular Surgery - Vascular Quality Initiative database from 2012 to 2021 was included and grouped into GPI versus non-GPI therapy (control). The primary outcome was in-hospital stroke or death, and secondary outcomes included in-hospital stroke/transient ischemic attack (TIA), death, myocardial infarction, and intracranial hemorrhage (ICH)/seizure. Patients were stratified by surgical approach (Transcarotid artery revascularization using flow reversal (TCAR) and transfemoral carotid artery stenting), and stepwise backward logistic regression analysis was conducted to evaluate major primary and secondary outcomes. A total of 50,628 patients underwent carotid revascularization. Of these, 4.4% of the patients received GPI. Mean age was similar between control versus GPI (71.35(9.67) vs. 71.36(10.20) years). Compared to the control group, patients who receive GPI are less likely to be on optimal medical therapy, including aspirin (83.0% vs. 88.1%), P2Y12 inhibitor (73.0% vs. 82.7%), and statin (82.3% vs. 86.0%) (All P<0.05). In addition, patients in the GPI group were more likely to undergo TCAR for carotid revascularization (52.2% vs. 48.4%) for emergent/urgent (29.4% vs. 16.8%) and symptomatic indications (55.5% vs. 49.7%) (All P<0.001). After stratifying by surgical approach, if patients underwent TFCAS and received a GPI, they were at increased odds of developing stroke/death (1.77(1.25-2.51)), death (odds ratio (OR) (95% CI): 1.67(1.07-2.61)), stroke/TIA (OR (95% confidence interval (CI)): 1.65(1.09-2.51)), and ICH/seizure (OR (95% CI): 2.13(1.23-3.68)) (All P<0.05). No difference was seen in outcomes between the 2 groups if undergoing TCAR. Patients who receive GPI were more likely to be symptomatic at presentation and less likely to be medically optimized before their carotid revascularization. Transfemoral access in patients receiving GPI was associated with increased odds of morbidity and mortality. However, this was not observed if undergoing TCAR. TCAR can be considered for its overall favorable results in high-risk patients who are not medically optimized.

Association Between Platelet Glycoprotein IIb/IIIa Inhibition and In-Hospital Outcomes in ST-Elevation Myocardial Infarction Patients Treated with Coronary Thrombus Aspiration: Findings from the CCC-ACS Project.

Thrombus aspiration in ST-elevation myocardial infarction (STEMI) with high thrombus burden did not improve clinical outcomes. The clinical efficacy of the bailout use of platelet glycoprotein IIb/IIIa inhibitors (GPIs) in this clinical scenario remains unknown. We assessed associations between GPI use and in-hospital major bleeds, ischemic events, and mortality among STEMI patients treated with percutaneous coronary intervention (PCI) and thrombus aspiration in a nationwide acute coronary syndrome registry (the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome project). A total of 5896 STEMI patients who received thrombus aspiration were identified, among which 56.3% received GPI therapy. In a 1-to-1 propensity-score-matched cohort, compared with STEMI patients not treated with GPI, GPI use was associated with a 69% increase in major in-hospital bleeds, with an odds ratio (OR) of 1.69, a 95% confidence interval (CI) of 1.08 to 2.65, and a nonsignificant reduction in ischemic events (OR: 0.61, 95% CI: 0.36 to 1.06), as well as a neutral effect on mortality (OR: 0.93, 95% CI: 0.55 to 1.58). However, among patients aged < 60years, GPI use was associated with a reduction in ischemic events (OR: 0.27, 95% CI: 0.08 to 0.98), and no significant increase in major bleeds was observed. In a nationwide registry, routine use of GPI following thrombus aspiration was not associated with reduced in-hospital ischemic events and mortality but at the cost of increased major bleeding. However, for patients aged < 60years, there may be a potential net benefit.

Glycoprotein IIb/IIIa inhibitor use in cardiogenic shock complicating myocardial infarction: The Portuguese Registry of Acute Coronary Syndromes

Introduction and objectivesCardiogenic shock (CS) complicates 5–10% of cases of myocardial infarction (MI). Whether glycoprotein IIb/IIIa inhibitors (GPIs) are beneficial in these patients is controversial. Our aim is to assess the prognostic impact of GPI use on in-hospital mortality and outcomes in patients with MI and CS undergoing percutaneous coronary intervention (PCI). MethodsBetween October 2010 and December 2019, 27578 acute coronary syndrome (ACS) patients were included in the multicenter Portuguese Registry of Acute Coronary Syndromes. Of these, 357 with an MI complicated by CS were included in the analysis and grouped based on whether they received GPI therapy (with GPI, n=107 and without GPI, n=250). The primary endpoint was in-hospital mortality. Secondary endpoints included successful PCI and in-hospital reinfarction and major bleeding. ResultsDemographics and cardiovascular risk factors did not differ between groups. ST-elevation MI patients were more likely to receive GPIs (95% vs. 83%, p=0.002). In-hospital mortality was similar between groups (OR 1.80, 95% CI 0.96–3.37). Only age and the use of inotropes or intra-aortic balloon pump were predictors of mortality. Also, no differences between groups were noted for successful PCI (OR 0.33, 95% CI 0.62–4.06), reinfarction (OR 0.77, 95% CI 0.15–3.90), or major bleeding (OR 1.68, 95% CI 0.75–3.74). ConclusionThe use of GPIs in the context of MI with CS did not significantly impact in-hospital outcomes.

Potent platelet inhibition with peri-procedural tirofiban may attenuate progression of atherosclerosis in patients with acute coronary syndromes.

Organization of platelet-rich thrombus at the site of plaque disruption may contribute to rapid progression of atherosclerosis. This study was conducted to investigate if potent platelet inhibition therapy in patients with acute coronary syndromes (ACS) mitigates plaque progression. Patients enrolled in the EROSION study who presented with ACS caused by plaque erosion and underwent serial imaging of the culprit lesion by optical coherence tomography at baseline, 1month, and 1year were included. Among 49 patients, 32 (65.3%) patients were treated with glycoprotein IIb/IIIa inhibitor (GPI) in addition to aspirin and ticagrelor. The increase in area stenosis from baseline to 1-year follow-up was significantly smaller in patients treated with GPI, compared to those without GPI therapy (4.8% [- 1.6 to 10.9] vs. 9.6% [4.0 to 21.3], p = 0.031). The cohort was divided into 2 groups based on culprit lesion phenotype at 1year: Group A, new layer formation at 1-year that was not present at baseline (n = 18); Group B, no new layer formation (n = 31). A new layer was less frequently found at 1year in patients treated with GPI than in those without GPI (25.0% vs. 58.8%, p = 0.019). Group A, compared to Group B, was associated with a greater increase in area stenosis (19.0 ± 16.4% vs. 3.7 ± 7.1%; p < 0.001). Potent platelet inhibition with GPI in patients with ACS caused by plaque erosion was associated with lower incidence of new layer formation and less plaque progression.

P957Survival benefits of routine glycoprotein IIb/IIIa inhibitors during primary PCI in ST-segment elevation myocardial infarction: A meta-analysis of randomised controlled trials

Abstract Background Cardiovascular guidelines recommend adjunct glycoprotein IIb/IIIa inhibitors (GPI) only in selected patients with acute ST-segment elevation myocardial infarction (STEMI). Purpose This study aimed to evaluate routine GPI use in STEMI treated with primary PCI. Methods Online databases were systematically searched for randomised controlled trials (RCTs) of routine GPI vs. control therapy in STEMI. Data from retrieved studies were abstracted and evaluated in a comprehensive meta-analysis using Mantel-Haenszel estimates of risk ratios (RR) as summary statistics. Results After systematic review, twenty-one RCTs with 8,585 patients were included: ten trials randomized tirofiban (T), nine abciximab (A), one eptifibatide (E), one trial used A+T; only one trial used DAPT with prasugrel/ ticagrelor. Routine GPI were associated with a significant reduction in all-cause mortality at 30 days (2.4% (GPI) vs. 3.2%; risk ratio (RR) 0.72; p=0.01) and 6 months (3.7% vs. 4.8%; RR 0.76; p=0.02), and a reduction in recurrent MI (1.1% vs. 2.1%; RR 0.55; p=0.0006), repeat revascularization (2.5% vs. 4.1%; RR 0.63; p=0.0001), TIMI flow &lt;3 after PCI (5.4% vs. 8.2%; RR 0.61; p&lt;0.0001) and ischemic stroke (RR 0.42; p=0.04). Major (4.7% vs. 3.4%; RR 1.35; p=0.005) and minor bleedings (7.2% vs. 5.1%; RR 1.39; p=0.006) but not intracranial bleedings (0.1% vs. 0%; RR 2.7; p=0.37) were significantly increased under routine GPI. Conclusions Routine GPI administration during primary PCI in STEMI resulted in mortality reduction, driven by reductions in recurrent ischemic events – however predominantly in trials pre-prasugrel/ticagrelor. Trials in contemporary STEMI management are needed to confirm these findings.

Comparison of In-Hospital Bleeding and Cardiovascular Events with High-Dose Bolus Tirofiban and Shortened Infusion to Short-Duration Eptifibatide as Adjunctive Therapy for Percutaneous Coronary Intervention

Potent platelet inhibition is one of the most important medical interventions to prevent ischemic complications during and after percutaneous coronary intervention (PCI). Practice has evolved with the introduction of potent oral P2Y12 inhibitors that provide quick, effective platelet inhibition, and the need for routine glycoprotein IIb/IIIa inhibitors (GPIs) has decreased. Additionally, a shorter duration of GPI infusion has been shown to be safe with adequate oral antiplatelet loading, but clinical outcome data are limited to eptifibatide. This single-center, retrospective cohort study analyzed in-hospital outcomes for patients who received adjunctive GPI therapy for PCI before and after an institution-wide switch to high-dose bolus tirofiban with shortened infusion from short-duration eptifibatide. The primary end point was a composite in-hospital outcome of major and minor bleeding and cardiovascular events (death, myocardial infarction, coronary artery bypass grafting, ischemic stroke, and target vessel revascularization). Secondary end points included bleeding and cardiovascular event types. A total of 357 and 446 patients received eptifibatide and tirofiban, respectively, from February 1, 2014 through September 30, 2017. Thirty five eptifibatide and 46 tirofiban patients experienced an in-hospital composite event (9.8% vs 10.3%, p = 0.81). There was no difference found between in-hospital bleeding (6.4% vs 5.4%, p = 0.52) or cardiovascular events (5.6% vs 6.5%, p = 0.60) with the use of eptifibatide or tirofiban, respectively. Multivariable analysis showed that patients with transradial access or an indication of unstable angina were less likely to experience an in-hospital composite event (OR 0.30 and 0.19, respectively, p <0.001 for both). In conclusion, the use of high-dose bolus tirofiban with shortened infusion versus short-duration eptifibatide was not associated with an increase of in-hospital bleeding or cardiovascular events.

At least seven days delayed stenting using minimalist immediate mechanical intervention (MIMI) in ST-segment elevation myocardial infarction: the SUPER-MIMI study.

The aim of this study was to ascertain whether a minimalist immediate mechanical intervention (MIMI) aiming to restore an optimal Thrombolysis In Myocardial Infarction (TIMI) flow in the culprit artery, followed ≥7 days later by a second percutaneous coronary intervention with intentional stenting, is safe in patients with ST-segment elevation myocardial infarction and large thrombotic burden. SUPER-MIMI was a prospective, observational trial conducted between January 2014 and April 2015 in 14 French centres. A total of 155 patients were enrolled. The pharmacological therapy was left to the operator's discretion. Eighty-one patients (52.3%) had glycoprotein IIb/IIIa inhibitors (GPI) initiated before the end of the first procedure. The median (interquartile range [IQR]) delay between the two procedures was eight (seven to 12) days. Infarct-related artery reocclusion between the two procedures (primary endpoint) occurred in two patients (1.3%), neither of whom received GPI treatment. TIMI flow was maintained or improved between the end of the first procedure and the beginning of the second procedure in all patients. Thrombotic burden and stenosis severity diminished significantly between the two procedures. Stents were ultimately implanted in 97 patients (62.6%). Deferred stenting (≥7 days) in patients with a high thrombus burden was safe on a background of GPI therapy.

Bivalirudin versus Heparin plus Glycoprotein IIb/IIIa Inhibitors in Women Undergoing Percutaneous Coronary Intervention: A Meta-Analysis of Randomized Controlled Trials.

Bivalirudin has been shown to be safe and efficacious compared with heparin plus glycoprotein IIb/IIIa inhibitor (GPI) in patients undergoing percutaneous coronary intervention (PCI). Whether bivalirudin would have the beneficial effects in female patients undergoing PCI remains unknown. We searched the literature for randomized controlled trials that assessed bivalirudin versus heparin plus GPI therapy in female patients undergoing PCI. The primary efficacy end point was major adverse cardiovascular events (MACE) within 30 days. The secondary efficacy end points were 30-day incidence of all-cause mortality, myocardial infarction (MI), urgent/ischemia-driven revascularization of target vessel. The safety end point was major bleeding up to 30 days. A total of 4,501 female patients were included in five randomized trials. No significant difference in MACE emerged between bivalirudin and heparin plus GPI at 30 days (8.15% vs 8.76%, RR 0.94, 95% CI 0.77–1.16, P = .57). There were no significant differences in rates of mortality (1.28% vs 1.91%, RR 0.74, 95% CI 0.45–1.20, P = .22), MI (5.46% vs 5.25%, RR 1.02, 95% CI 0.79–1.32, p = .88), or target vessel revascularization (2.13% vs 1.65%, RR 1.43, 95% CI 0.88–2.30, P = .15). Compared with heparin plus GPI, bivalirudin was associated with a significant reduction in 30-day major bleeding (5.32% vs 9.20%, RR 0.58, 95% CI 0.47–0.72, P < .0001). In conclusion, bivalirudin is associated with a significant reduction in 30-day major bleeding without increased ischemic events compared with heparin plus GPI in female patients undergoing PCI.

Evaluation of Ischemic and Bleeding Risks Associated With 2 Parenteral Antiplatelet Strategies Comparing Cangrelor With Glycoprotein IIb/IIIa Inhibitors

In the context of contemporary pharmacotherapy, optimal antiplatelet management with percutaneous coronary intervention (PCI) has not been well established. To compare the ischemic and bleeding risks associated with glycoprotein IIb/IIIa inhibitors (GPIs) and a potent P2Y12 antagonist, cangrelor, in patients undergoing PCI. An exploratory analysis of pooled patient-level data from the 3 phase 3 Cangrelor vs Standard Therapy to Achieve Optimal Management of Platelet Inhibition (CHAMPION PCI, CHAMPION PLATFORM, and CHAMPION PHOENIX) trials of patients undergoing elective or nonelective PCI. The participants included 10 929 patients assigned to cangrelor but not receiving GPIs (cangrelor alone) and 1211 patients assigned to clopidogrel (or placebo) and receiving routine GPIs (clopidogrel-GPI). Patients requiring bailout or rescue GPI therapy were excluded. To account for risk imbalances, 1:1 propensity score matching based on 16 baseline clinical variables yielded 1021 unique matched pairs. The present study's data analysis was conducted from October 28, 2015, to August 6, 2016. The primary efficacy end point was the composite of all-cause mortality, myocardial infarction, ischemia-driven revascularization, or stent thrombosis at 48 hours. Safety was assessed by 3 validated bleeding scales (Global Use of Strategies to Open Occluded Coronary Arteries [GUSTO], Thrombolysis in Myocardial Infarction [TIMI], and Acute Catheterization and Urgent Intervention Triage) and requirement for blood transfusions. Of the 12 140 patients included in the analysis, 8779 were men (72.3%), and the mean (SD) age was 63.2 (11.3) years. Patients in the clopidogrel-GPI group were more likely to be male (75.6% vs 71.9%), younger (median, 60 [range, 23-91] years vs 64 [range, 26-95] years), enrolled from the United States (77.9% vs 40.0%), and present with an acute coronary syndrome, but they had lower comorbid disease burden and were less likely to receive bivalirudin (8.8% vs 27.3%). In the matched cohorts, the rates of the primary efficacy end point were not significantly different between the cangrelor alone and clopidogrel-GPI groups (2.6% vs 3.3%; odds ratio [OR], 0.79; 95% CI, 0.48-1.32). There was a nonsignificant trend toward lower rates of GUSTO-defined severe/life-threatening bleeding with cangrelor alone compared with clopidogrel-GPI (0.3% vs 0.7%; OR, 0.43; 95% CI, 0.11-1.66). Rates of TIMI-defined major or minor bleeding were significantly lower in patients treated with cangrelor alone (0.7% vs 2.4%; OR, 0.29; 95% CI, 0.13-0.68). Based on a pooled analysis from the 3 phase 3 CHAMPION trials, cangrelor alone was associated with similar ischemic risk and lower risk-adjusted bleeding risk compared with clopidogrel-GPIs. clinicaltrials.gov Identifiers: NCT00305162, NCT00385138, and NCT01156571.

Glycoprotein IIb/IIIa inhibitor associated severe thrombocytopenia in patients with coronary artery disease: Clinical course and outcomes

Thrombocytopenia, both at baseline and acquired throughout admission is associated with poor clinical outcomes in patients with coronary artery disease. It is not known whether severe thrombocytopenia in patients receiving glycoprotein IIb/IIIa inhibitors (GPI) carries the same risk as thrombocytopenia from other aetiologies. We identified 50 consecutive patients referred for percutaneous coronary intervention (PCI) who developed severe thrombocytopenia (<50 × 109 cells/l) and followed their clinical course to 30 days. Two groups were compared: (1) severe thrombocytopenia following GPI usage and (2) severe thrombocytopenia without exposure to GPI. Baseline platelet counts were higher in GPI group (201 ± 62 vs. 112 ± 83 × 109 cells/l, p < 0.05). Patients in GPI group had more profound thrombocytopenia yet quicker recovery of platelet counts. The GPI group received fewer blood product transfusions (red cells: 0.1 ± 0.4 vs. 1.3 ± 2.0, p < 0.05, platelets: 0.22 ± 0.6 vs. 1.1 ± 1.7, p < 0.05) and had lower event rates for the primary end point of 30-day mortality (3.7% vs. 42.1%, p < 0.05), and for major bleeding (0% vs. 15.8%, p < 0.05).In conclusion, GPI associated severe thrombocytopenia follows a distinct clinical course when compared to severe thrombocytopenia due to other aetiologies. Our results suggest that patients who develop severe thrombocytopenia following GPI therapy may be managed conservatively with careful monitoring.

Drug-eluting stents and glycoprotein IIb/IIIa inhibitors in vessels at low anatomic risk: A retrospective analysis of previously published data from the Basel Stent Kosten Effektivitäts Trial

Background: Drug-eluting stents (DESs) are associated with late stent thromboses, but the exact mechanism of action is unknown. Objective: The goal of this article was to assess the clinical interaction of glycoprotein IIb/IIIa inhibitors (GPIs) with different stent and vessel types in unselected patients undergoing percutaneous coronary intervention (PCI). Methods: This was a predefined retrospective analysis of the randomized controlled Basel Stent Kosten Effektivitats Trial (BASKET), which compared DES with bare-metal stents (BMSs) in patients undergoing PCI. Patients were compared for major adverse clinical events in relation to GPI use (abciximab and tirofiban) after 18 months. In a subgroup analysis prespecified in the study protocol, specific regard was given to angiographic groups at different risk levels for late events (high-risk vessels [ie, small vessels with a diameter <3.0 mm and saphenous vein grafts], and low-risk vessels [ie, large native vessels ≥3.0 mm]). Baseline differences between patients with or without GPI use were identified and incorporated into a multivariable Cox proportional hazards regression analysis if different at a <0.05 level. Results: A total of 826 patients (650 males, 176 females) were enrolled in BASKET; 301 (36%) received GPI therapy. Of these 301 patients, 255 (85%) received abciximab and 46 (15%) received tirofiban. After 18 months, the rate of cardiac death and nonfatal myocardial infarction was higher in patients with GPI use than in those without GPI use (35/301 [12%] vs 32/525 [6%]; P = 0.005). In patients undergoing PCI in anatomically low-risk vessels and receiving GPI therapy, there was a higher rate of cardiac death and nonfatal myocardial infarction at 18 months with a DES versus a BMS (22/151 [15%] vs 3/66 [5%]; P = 0.033). In patients undergoing PCI in anatomically low-risk vessels and without GPI therapy, there was no significant difference for cardiac death and nonfatal myocardial infarction (DES vs BMS, 11/207 [5%] vs 6/134 [4%]). In the multivariable analysis, GPI use (hazard ratio = 2.93; 95% CI, 1.53-5.63; P = 0.001) and age (hazard ratio = 1.034 per year increase; 95% CI, 1.008-1.062; P = 0.012) remained the only significant independent predictors of outcome. Interaction of stent type and GPI use was significant ( P = 0.006). Conclusions: This retrospective analysis of the BASKET data found that GPIs and DESs used in patients with large native vessels may have an adverse interaction in terms of late stent thromboses. However, large prospective studies are needed to confirm these findings.

Bolus-only versus bolus + infusion of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention

The present study was done to analyze if glycoprotein IIb/IIIa inhibitors (GPI) bolus-only will reduce vascular/bleeding complications and cost with similar major adverse cardiac events (MACE) when compared with GPI bolus + infusion. Evidence-based therapy of GPI inhibitors during percutaneous coronary intervention (PCI) incorporates intravenous bolus followed by 12 to 18 hours of infusion. However, GPI bolus + infusion may increase vascular/bleeding complications and may not reduce MACE when compared with GPI bolus-only. From January 1, 2003, to December 31, 2004, 2,629 consecutive patients received GPI during PCI at a single center. Of these, 1,064 patients received GPI bolus + infusion in 2003 and were compared with 1,565 patients that received GPI bolus-only in 2004. Baseline characteristics were similar in both groups. Patients receiving GPI bolus-only had reduced vascular/bleeding complications when compared with bolus + infusion (4.9% vs 7%, P < .05, odds ratio 0.62, 95% confidence interval 0.45-0.89). Furthermore, ischemic complications were similar in both groups, including periprocedural creatine kinase-MB enzyme release (12.8% vs 15.3%, P = NS), MACE at 30 days (3.2% vs 3%, P = NS), and death and myocardial infarction at 1 year (7.1% vs 7.8%, P = NS). In addition, GPI bolus-only reduced cost in US dollars ($323 vs $706, P < .001) and increased ambulatory PCI (13.1% vs 3.2%, P < .01), with reduced length of stay (1.1 vs 1.6 days, P < .01), when compared with GPI bolus + infusion. Glycoprotein inhibitor bolus-only reduces vascular/bleeding complications with similar MACE and reduced cost when compared with GPI bolus + infusion. In addition, GPI bolus-only improved ambulatory PCI and reduced length of stay. These results are consistent with a safer and cost-effective strategy for bolus-only when GPI therapy is considered during PCI.

Glycoprotein IIb-IIIa Inhibitors for Acute Ischemic Stroke

Glycoprotein IIb-IIIa Inhibitors for Acute Ischemic Stroke

Cost-Effectiveness Analysis of Antithrombotic Therapy in Nonurgent Percutaneous Coronary Intervention

To perform a cost-effectiveness analysis comparing three treatment approaches during nonurgent percutaneous coronary intervention (PCI): bivalirudin with provisional glycoprotein (GP) IIb-IIIa inhibitor therapy, unfractionated heparin (UFH) with eptifibatide, and UFH with abciximab. Literature-based decision model from an institutional perspective. Patient data from the Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE)-2 study and three other randomized controlled trials that included UFH and routine GP IIb-IIIa inhibitor (eptifibatide or abciximab) therapy. All included studies were comparable based on patient population, procedural techniques, and general treatment approaches. We included patient populations undergoing contemporary nonurgent PCI to identify probabilities of success or complications (myocardial infarction, urgent revascularization, thrombocytopenia, and major or minor bleeding at 30 days). Costs were assigned to each outcome by incorporating diagnosis-related group-- and/or Current Procedural Terminology--associated costs, institutional drug acquisition costs, and unit replacement costs of platelets and red blood cells. In the base-case analysis, the use of bivalirudin with provisional GP IIb-IIIa inhibitor therapy dominated the UFH and planned GP IIb-IIIa inhibitor approach: UFH with eptifibatide was 74 US dollars more expensive and 1.2% less effective, and UFH with abciximab was 777 US dollars more expensive and 2.3% less effective. Sensitivity analyses indicated that the model results were robust, but also revealed that bivalirudin lost its cost-effectiveness, resulting in UFH with eptifibatide becoming more cost-effective, when two or more vials of bivalirudin were necessary in greater than 27% of cases or when the use of provisional GP IIb-IIIa inhibitor therapy exceeded 20%. This analysis indicates that bivalirudin with provisional GP IIb-IIIa inhibitor therapy is the most cost-effective antithrombotic treatment strategy in nonurgent PCI when its use and dosing are consistent with the REPLACE-2 trial.

Glycoprotein IIb/IIIa Inhibitors in Patients with End-Stage Renal Disease

To determine whether glycoprotein IIb/IIIa inhibitors (GPIs) are effective and safe as adjunctive therapy for percutaneous coronary intervention (PCI) in patients with end-stage renal disease (ESRD). MEDLINE (1966-June 2004), EMBASE (1980-June 2004), and International Pharmaceutical Abstracts (1970-June 2004) were searched, in addition to a manual bibliographic search. Even though GPIs have an established role as adjunctive therapy in PCI, little is known about their use in patients with ESRD. We found 3 reports describing experience with abciximab in this population. Based on the limited information from registries and a retrospective chart review, it is difficult to draw definitive conclusions about the utility of GPIs in ESRD. The decision to use abciximab in this population must be made on an individual case basis. Studies are needed to evaluate the benefit versus risk of GPI therapy in ESRD.

Administration of glycoprotein IIb-IIIa inhibitors in patients with ST-segment elevation myocardial infarction.

Patients with ST-segment elevation acute myocardial infarction require immediate reperfusion therapy. Reperfusion therapy can be provided by either pharmacologic or mechanical means. Pharmacologic reperfusion therapy consists of administering fibrinolytics, whereas mechanical reperfusion consists of performing percutaneous intervention, usually with stent placement. Each approach has been shown to decrease mortality, but each has disadvantages in establishing flow in the infarct-related artery. Regardless of the approach, during an acute myocardial infarction, activation and externalization of glycoprotein (GP) IIb-IIIa receptors occur on the surface of platelets. The GP IIb-IIIa inhibitors block the binding of fibrinogen to these platelet receptors. These inhibitors have been investigated in combination with both reperfusion strategies. The goal of adding GP IIb-IIIa inhibitor therapy to either reperfusion approach is to obtain better early, complete, and sustained reperfusion. Subsequently, this should lead to better clinical outcomes for patients with ST-segment elevation acute myocardial infarction. Although no mortality benefit has been seen with the addition of GP IIb-IIIa inhibitor therapy, ischemic complications have been reduced significantly.

Understanding thrombocytopenia and antigenicity with glycoprotein IIb-IIIa inhibitors

Platelet glycoprotein (GP) IIb-IIIa receptor antagonists are being used with increasing frequency in the settings of percutaneous coronary interventions and acute ischemic syndromes. The development of thrombocytopenia after GP IIb-IIIa blockade has been observed to some extent with all parenteral GP IIb-IIIa inhibitors studied to date and could potentially limit their effectiveness. The incidence and severity of thrombocytopenia has varied in large clinical trials with GP IIb-IIIa inhibitors, presumably as a consequence of the different structural and pharmacokinetic characteristics of the agents, the dose administered and duration of use, repetition of exposure, and the various drugs coadministered with these agents. Certain baseline characteristics may be predictive. In most cases, severe thrombocytopenia associated with the use of GP IIb-IIIa receptor antagonists was readily reversible with platelet transfusion and was not usually associated with major clinical sequelae. Although the exact mechanisms responsible for thrombocytopenia after GP IIb-IIIa blockade are poorly understood, an immune mechanism is suggested in which the binding of the antagonist to GP IIb-IIIa receptors leads to the exposure of ligand-induced binding sites recognized by preexisting or induced antibodies. Alternatively, the receptor–drug metabolite complex itself may induce an immune response. All patients receiving parenteral GP IIb-IIIa inhibitors should be monitored within 24 hours of initiation of therapy for the development of thrombocytopenia. An algorithm for the detection and management of thrombocytopenia after GP IIb-IIIa inhibitor therapy is proposed. (Am Heart J 1999;138:S317-S326.)

Safety of glycoprotein IIb-IIIa inhibitors: A heart surgeon’s perspective

Platelet-mediated coronary thrombosis is the primary pathophysiologic mechanism of acute coronary syndromes (ACS) and acute ischemic complications of percutaneous coronary intervention (PCI). The final common pathway of platelet aggregation that leads to thrombotic occlusion of coronary arteries involves cross-linking of receptor glycoprotein (GP) IIb-IIIa on adjacent platelets by adhesive plasma proteins, primarily fibrinogen. Clinical trials of several GP IIb-IIIa inhibitors have demonstrated an unequivocal clinical benefit of this potent antithrombotic therapy in patients with ACS as well as in those undergoing PCI. Nevertheless, a significant number of patients with ischemic heart disease may still be expected to require elective or emergency coronary artery bypass graft (CABG) after treatment with GP IIb-IIIa inhibitors. In the emergency CABG setting, complications and platelet blockade with GP IIb-IIIa inhibitors may further enhance the already heightened risk of bleeding as compared with elective procedures. This issue became apparent in the first large clinical trial of the GP IIb-IIIa inhibitor abciximab (c7E3 Fab, ReoPro ®; Centocor, Malvern, Pa, and Eli Lilly and Co, Indianapolis, Ind) in patients undergoing high-risk PCI. In this study, mortality rates and bleeding complications were increased among patients undergoing emergency CABG after treatment with a bolus plus infusion of abciximab. Subsequent clinical experience also suggests that the potential for bleeding complications related to emergency CABG may be increased in patients treated with abciximab, particularly if the drug is discontinued within 6 hours of the operation. Higher bleeding risk with abciximab is a result of its prolonged antiplatelet effect, which is in contrast to the readily reversible platelet blockade provided by more recently developed small-molecule GP IIb-IIIa inhibitors such as the peptide eptifibatide (Integrilin ®; COR Therapeutics, South San Francisco, Calif, and Key Pharmaceuticals, Kenilworth, NJ) and the nonpeptide tirofiban HCl (MK-383, Aggrastat ®; Merck & Co, Whitehouse Station, NJ). Therefore, among patients requiring CABG after treatment with GP IIb-IIIa inhibitors, eptifibatide and tirofiban may be associated with fewer bleeding episodes than is abciximab. With recent approval of eptifibatide for patients with ACS and those scheduled for PCI and of tirofiban for patients with ACS, the number of patients receiving GP IIb-IIIa inhibitor therapy who subsequently undergo CABG is expected to increase significantly. Strategies for improved management of bleeding complications in these patients, including the choice of a GP IIb-IIIa inhibitor, are clearly needed and are discussed in detail. (Am Heart J 1999;138:S307-S316.)

Bleeding complications of glycoprotein IIb-IIIa receptor inhibitors

Large clinical studies have demonstrated an unequivocal clinical benefit of antithrombotic therapy with inhibitors of the platelet surface-membrane glycoprotein (GP) IIb-IIIa receptor in a broad range of patients with ischemic heart disease. Potent antiplatelet effects of these agents, however, may increase the risk of bleeding complications, as occurred in the first large evaluation of this therapy, the Evaluation of c7E3 for Prevention of Ischemic Complications (EPIC) trial with abciximab (c7E3 Fab; ReoPro ®; Centocor, Malvern, Pa). Although the incidence of bleeding events in subsequent studies has been reduced through the use of a low-dose, weight-adjusted heparin regimen and early removal of vascular sheaths in patients who have undergone percutaneous coronary interventions, hemorrhage continues to be the most common complication of GP IIb-IIIa inhibitor therapy. This review summarizes current experience related to bleeding complications with various GP IIb-IIIa inhibitors and suggests strategies for improved management of bleeding in patients receiving these agents. (Am Heart J 1999;138:S287-S296)

Minimizing bleeding complications of percutaneous coronary intervention and glycoprotein IIb-IIIa antiplatelet therapy

Percutaneous coronary intervention in patients with coronary artery disease can lead to thrombotic occlusion of the artery and to subsequent ischemic complications. Patients undergoing these procedures have been treated with aspirin, heparin, or both as a means of preventing thrombosis. The arsenal of antithrombotic agents has recently been augmented by the addition of a new class of drugs the platelet receptor glycoprotein (GP) IIb-IIIa inhibitors, which include abciximab, eptifibatide, and tirofiban. Unlike aspirin or heparin, which inhibit some but not all pathways leading to thrombosis, GP IIb-IIIa inhibitors block the final common pathway of platelet aggregation. When used in conjunction with aspirin and heparin, GP IIb-IIIa inhibitors have yielded favorable clinical outcomes, reducing the incidence of death, myocardial infarction, and urgent intervention. However, GP IIb-IIIa inhibitors also have been associated with an increased risk of bleeding complications, especially at the femoral access site. This presents new challenges for nurses charged with the care of patients treated with these agents. The goal of nursing care for this population is to ensure the optimal benefits of GP IIb-IIIa inhibitor therapy while simultaneously preventing or minimizing groin bleeding in patients undergoing percutaneous coronary procedures. (Am Heart J 1999;138:S297-S306.)