Randomized Clinical Trial of Abciximab in Diabetic Patients Undergoing Elective Percutaneous Coronary Interventions After Treatment With a High Loading Dose of Clopidogrel

Antithrombotic Treatment in Diabetes Mellitus: A Review of the Literature about Antiplatelet and Anticoagulation Strategies Used for Diabetic Patients in Primary and Secondary Prevention

Background:

Diabetes mellitus (DM) is on the rise globally. Its prevalence has nearly doubled during the last two decades and it is estimated to affect 8.8% of the global population. Cardiovascular disease (CVD) is the leading cause of death in diabetic population and despite modern anti-inflammatory and cardioprotective therapeutic strategies diabetic patients have at least a twice fold risk of cardiovascular events. Prothrombotic state in DM is associated with multiple determinants such as platelet alterations, oxidative stress, endothelial changes, circulating mediators. Thus, proper antithrombotic strategies to reduce the risk of CVD in this population is critical.

Methods:

This article reviews the current antiplatelet and anticoagulant agents in the aspect of primary and secondary prevention of CVD in the diabetic population.

Results:

The use of aspirin may be considered only at high-risk patients in the absence of contraindications. Cangrelor was not inferior to clopidogrel in preventing the composite outcome of CV death, myocardial infraction and revascularization without increasing major bleeding. Triple therapy in the subpopulation with DM significantly reduced the composite primary outcome of CV death, myocardial infraction or repeat target lesion revascularization. That was not the case for stent thrombosis, which was similar in both groups. Importantly, triple therapy did not result in increased bleeding complications, which were similar in both groups. However, cilostazol is linked to various adverse effects (e.g., headache, palpitations, and gastrointestinal disturbances) that drive many patients to withdrawal.

Conclusion:

In conclusion, DM is a rapidly growing disease that increases the risk of CVD, AF, and CV mortality. Proper antithrombotic strategies to reduce CVD risk in DM is a necessity. Also, new antithrombotic treatments and combination therapies may play a critical role to overcome antiplatelet resistance in DM patients and reduce morbidity and mortality attributed to CVD.

Periprocedural Myocardial Injury: Pathophysiology, Prognosis, and Prevention

The definition and clinical implications of myocardial infarction occurring in the setting of percutaneous coronary intervention have been the subject of unresolved controversy. The definitions of periprocedural myocardial infarction (PMI) are many and have evolved over recent years. Additionally, the recent advancement of different imaging modalities has provided useful information on a patients' pre-procedural risk of myocardial infarction. Nonetheless, questions on the benefit of different approaches to prevent PMI and their practical implementation remain open. This review aims to address these questions and to provide a current and contemporary perspective.

Using PAR4 Inhibition as an Anti-Thrombotic Approach: Why, How, and When?

Protease-activated receptors (PARs) are a family of four GPCRs with a variety of cellular functions, yet the only advanced clinical endeavours to target these receptors for therapeutic gain to date relates to the impairment of platelet function for anti-thrombotic therapy. The only approved PAR antagonist is the PAR1 inhibitor, vorapaxar—the sole anti-platelet drug against a new target approved in the past 20 years. However, there are two PARs on human platelets, PAR1 and PAR4, and more recent efforts have focused on the development of the first PAR4 antagonists, with first-in-class agents recently beginning clinical trial. Here, we review the rationale for this approach, outline the various modes of PAR4 inhibition, and speculate on the specific therapeutic potential of targeting PAR4 for the prevention of thrombotic conditions.

Integrin ß1 polymorphisms and bleeding risk after coronary artery stenting

Bleeding complications following percutaneous coronary intervention associate with increased mortality. However, the underlying molecular mechanisms are insufficiently understood. Platelet recruitment and activation at sites of vascular injury depends on the function of integrin adhesion receptors. Besides GPIIbIIIa as the most abundant integrin receptor, platelets relevantly express ß1 integrins. Experimental evidence from in vivo studies suggests a significant role of ß1 integrins in primary haemostasis. However, little is known about the clinical impact of genetic alterations of the β1 subunit, which might contribute to bleeding complications in patients. In this study, we performed DNA sequencing of patients suffering from bleeding complications after coronary artery stenting according to TIMI or BARC classification. We isolated DNA samples from 741 patients out of a cohort from 14,160 patients recruited in seven randomized clinical trials between June 2000 and May 2011. Subsequently, Sanger sequencing was performed covering the β1 integrin cytoplasmic activation domain (exon16) and its non-coding upstream region. Out of 764 patients suffering from bleeding complications, 741 DNA samples were successfully sequenced. Genotype variation was detected for SNP rs2153875 located within the non-coding upstream region with following allele frequency in study population: CC (7.3%), CA (35%) and AA (57.8%), which is similar to a general population cohort. Further, genotype variation in SNP rs2153875 do not associate with the frequency of TIMI or BARC classified access or non-access site bleedings. Genotype variations of the β1 integrin activation domain do not associate with bleeding risk after PCI.

Perioperative Bridging With Glycoprotein IIb/IIIa Inhibitors Versus Cangrelor: Balancing Efficacy and Safety

OBJECTIVE

To review the efficacy and safety of perioperative administration of intravenous (IV) antiplatelet agents as a substitute for oral P2Y₁₂ inhibitors and to provide clinicians guidance on optimal and cost-effective use of these medications.

DATA SOURCES

A MEDLINE literature search (1950 to November 2018) was performed using the key search terms abciximab, bridging, cangrelor, cardiac surgery, coronary artery bypass surgery, eptifibatide, intravenous antiplatelet agent, and tirofiban. Additional references were identified from a review of literature citations.

STUDY SELECTION AND DATA EXTRACTION

In all, 18 original research reports and case reports/series were included in the review.

DATA SYNTHESIS

Prevention of postoperative bleeding is critical to decrease morbidity and mortality after cardiac surgery. IV antiplatelet medications have short half-lives and are frequently used to substitute for oral P2Y₁₂ inhibitors to allow platelet function recovery before procedures. Functional recovery of platelets is delayed after abciximab discontinuation and increases postoperative bleeding risk. Eptifibatide and tirofiban have similar pharmacokinetic/pharmacodynamic properties and comparable efficacy and safety in the setting of perioperative bridging. Cangrelor may be considered in patients with renal insufficiency as decreased clearance of eptifibatide or tirofiban may increase the risk of postoperative bleeding. Relevance to Patient Care and Clinical Practice: Comparative studies of IV antiplatelet medications have not been published. Appropriate use of IV antiplatelet medications can prevent perioperative ischemic events and bleeding.

CONCLUSIONS

Eptifibatide, tirofiban, and cangrelor are preferred over abciximab as a perioperative bridge. The choice of agent should be tailored to clinical characteristics of the patient and institutional acquisition costs.

Intravenous antiplatelet therapies (glycoprotein IIb/IIIa receptor inhibitors and cangrelor) in percutaneous coronary intervention: from pharmacology to indications for clinical use

Oral antiplatelet drugs are crucially important for patients with acute coronary syndrome or stable coronary artery disease undergoing percutaneous coronary intervention (PCI). In recent decades, several clinical trials have focused on reducing periprocedural ischemic events in patients undergoing PCI by means of more rapid platelet inhibition with the use of intravenous antiplatelet drugs. Glycoprotein IIb/IIIa receptor inhibitors (GPIs) block the final common pathway of platelet aggregation and enable potent inhibition in the peri-PCI period. In recent years, however, the use of GPIs has decreased due to bleeding concerns and the availability of more potent oral P2Y12 inhibitors. Cangrelor is an intravenous P2Y12 receptor antagonist. In a large-scale regulatory trial, cangrelor administration during PCI allowed for rapid, potent and rapidly reversible inhibition of platelet aggregation, with an anti-ischemic benefit and no increase in major bleeding. This article aims to provide an overview of general pharmacology, supporting evidence and current status of intravenous antiplatelet therapies (GPIs and cangrelor), with a focus on contemporary indications for their clinical use.

Effect of tailored use of tirofiban in patients with Non-ST-elevation acute coronary syndrome undergoing percutaneous coronary intervention: a randomized controlled trial

Background

We conducted a randomized controlled trial to investigate whether an additional platelet inhibition with tirofiban would reduce the extent of myocardial damage and prevent periprocedural myonecrosis in patients with Non-ST-elevation acute coronary syndrome (NSTE-ACS) with a high residual platelet activity (HPR).

Methods

Patients with an HPR, defined as P₂Y₁₂ reaction unit (PRU) > 230, were randomly assigned to group A (tirofiban treatment, n = 30) or C1 (n = 30) and patients without an HPR to C2 (n = 78). Periprocedural myocardial damage was assessed using the area under the curve (AUC) of serial cardiac enzyme levels from the time of the procedure to post-36 h. Periprocedural myonecrosis incidence was evaluated.

Results

The troponin I AUC was not different between the groups (197.2 [41.5395.7], 37.9 [8.9313.9], 121.3 [43.7481.8] h∙ng/mL; p = 0.088). The results did not change when the baseline levels were adjusted (365.3 [279.5, 451.1], 293.0 [207.1, 379.0], and 298.0 [244.7, 351.3] h∙ng/mL; p = 0.487). The rate of periprocedural myonecrosis was also not different between the groups (53.0% vs. 50.0% vs. 33.3%, p = 0.092). The CK-MB isoenzyme analysis showed similar results. No difference in complications was noted.

Conclusion

Additional tirofiban administration was not beneficial to patients with NSTE-ACS even with an HPR.

Trial registration

Clinical trial no. NCT03114995, registered 11 April, 2017, retrospectively.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0938-6) contains supplementary material, which is available to authorized users.

Routine angiographic follow-up versus clinical follow-up in patients with diabetes following percutaneous coronary intervention with drug-eluting stents in Korean population

AIMS

The usefulness of routine angiographic follow-up (RAF) and clinical follow-up (CF) after percutaneous coronary intervention (PCI) in patients with diabetes is not well understood. We compare 3-year clinical outcomes of RAF and CF in diabetic patients underwent PCI with drug-eluting stents (DES).

METHODS

A total of 843 patients with diabetes who underwent PCI with DES were enrolled. RAF was performed at 6-9 months after PCI (n = 426). Rest of patients were medically managed and clinically followed (n = 417); symptom-driven events were captured. After propensity score matched analysis, 2 propensity-matched groups (262 pairs, n = 524, C-statistic = 0.750) were generated. The primary endpoint was major adverse cardiac events (MACE), the composite of total death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), non-target vessel revascularization (Non-TVR).

RESULTS

During the 3-year follow-up period, the cumulative incidence of target lesion revascularization [TLR: hazard ratio (HR), 4.07; 95% confidence interval (CI), 1.18-9.34; p = 0.001], target vessel revascularization (TVR: HR, 4.02; 95% CI, 1.93-8.40; p < 0.001), non-TVR (HR, 4.92; 95% CI, 1.68-14.4; p = 0.004) and major adverse cardiac events (MACE: HR, 2.53; 95% CI, 1.60-4.01, p < 0.001) were significantly higher in the RAF group. However, the incidence of total death, non-fatal MI were similar between the two groups.

CONCLUSIONS

RAF following index PCI with DES in patients with diabetes was associated with increased incidence of revascularization and MACE without changes of death or re-infarction rates and increased TLR and TVR rates in both first- and second-generation DES.

Subgroup analyses with special reference to the effect of antiplatelet agents in acute coronary syndromes

Controlled trials estimate treatment effects averaged over the reference population of subjects. However, physicians are interested in whether the treatment effect varies across subgroups (effect heterogeneity) in order to target specific subgroups to maximise the benefit of treatment and minimise harm. Therefore, large clinical trials of antiplatelet agents include subgroup analyses that examine whether treatment effects differ between subgroups of subjects identified by baseline characteristics. Reporting subgroup is pervasive and often accompanied by claims of difference of treatment effects between subgroups with potential important implications for clinical practice. However, subgroup-specific analyses of clinical trial data have inherent limitations that reduce their reliability. These include reduced statistical power, failure to specify the subgroups of interest a priori, failure to account for examining large numbers of subgroups, lack of strong rationale for biological response modification, and performing analyses based on variables measured post randomisation or in trials showing no overall difference between treatments. Rules for interpretation of subgroup findings in subgroups have been suggested but are frequently not applied. In this article we draw attention to the pitfalls of subgroup analyses in the context of recent trials of antiplatelet agents.

GPIIb/IIIa inhibitors: From bench to bedside and back to bench again

From the discovery of the platelet glycoprotein (GP) IIb/IIIa and identification of its central role in haemostasis, the integrin GPIIb/IIIa (αIIbβ3, CD41/CD61) was destined to be an anti-thrombotic target. The subsequent successful development of intravenous ligand-mimetic inhibitors occurred during a time of limited understanding of integrin physiology. Although efficient inhibitors of ligand binding, they also mimic ligand function. In the case of GPIIb/IIIa inhibitors, despite strongly inhibiting platelet aggregation, paradoxical fibrinogen binding and platelet activation can occur. The quick progression to development of small-molecule orally available inhibitors meant that this approach inherited many potential flaws, which together with a short half-life resulted in an increase in mortality and a halt to the numerous pharmaceutical development programs. Limited clinical benefits, together with the success of other anti-thrombotic drugs, in particular P2Y12 ADP receptor blockers, have also led to a restrictive use of intravenous GPIIb/ IIIa inhibitors. However, with a greater understanding of this key platelet-specific integrin, GPIIb/IIIa remains a potentially attractive target and future drug developments will be better informed by the lessons learnt from taking the current inhibitors back to the bench. This overview will review the physiology behind the inherent problems of a ligand-based integrin inhibitor design and discuss novel promising approaches for GPIIb/IIIa inhibition.

A randomized trial assessing the impact of three different glycoprotein IIb/IIIa antagonists on glycoprotein IIb/IIIa platelet receptor inhibition and clinical endpoints in patients with acute coronary syndromes

AIMS

To compare three glycoprotein IIb/IIIa receptor antagonists (GPIs) in terms of platelet inhibition and major adverse cardiac events (MACEs), and assess the rate of bleeding and MACEs between GPIs and coadministered P2Y12 agents.

METHODS

Eighty-three acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) with planned GPI use were randomized to receive high-dose bolus tirofiban, double-bolus eptifibatide, or abciximab followed by a 12-hour infusion. Glycoprotein IIb/IIIa platelet receptor inhibition was measured at baseline and at 10 minutes, 1 hour, and 24 hours postbolus dose. Major adverse cardiac events and bleeding complications at 30 days were documented. The incidence of MACEs and bleeding in patients receiving ticagrelor or prasugrel were compared to those given clopidogrel.

RESULTS

There were no statistically significant differences in platelet inhibition between GPIs at 10 minutes (P=.085) and 1 hour (P=.337). At 24 hours, abciximab achieved statistically significantly higher median [interquartile range] platelet inhibition (75 [65-88]%) compared to tirofiban (28 [3-56]%; P<.0001) and eptifibatide (44 [31-63]%; P=.007). There were no differences in bleeding or MACEs depending on GPI or P2Y12 inhibitor administered.

CONCLUSIONS

Glycoprotein receptor inhibitors achieve similar levels of platelet inhibition at 10 minutes and 1 hour; however, abciximab maintains this benefit 24 hours after bolus dose. We did not witness an increased rate of bleeding in patients given new potent P2Y12 inhibitors and a GPI in the modern era.

Comparison of heparin, bivalirudin, and different glycoprotein IIb/IIIa inhibitor regimens for anticoagulation during percutaneous coronary intervention: A network meta-analysis

BACKGROUND/PURPOSE

Numerous GPIs are available for PCI. Although they were tested in randomized controlled trials, a comparison between the different GPI strategies is lacking. Thus, we performed a Bayesian network meta-analysis to compare different glycoprotein IIb/IIIa inhibitor (GPI) strategies with heparin and bivalirudin for percutaneous coronary intervention (PCI).

METHODS

MEDLINE, Cochrane CENTRAL, and ClinicalTrials.gov were searched by two independent reviewers for randomized controlled trials comparing high-dose bolus tirofiban, abciximab, eptifibatide, heparin with provisional glycoprotein IIb/IIIa inhibitors, and bivalirudin with provisional GPI that reported clinical outcomes. Mixed treatment comparison model generation was performed to directly and indirectly compare between different anticoagulation strategies for all-cause mortality, myocardial infarction, major adverse cardiovascular events, major bleeding, minor bleeding, need for transfusion, and thrombocytopenia.

RESULTS

A total of 41 randomized controlled trials with 38,645 patients were included in the analysis, among which 2654 were randomized to high-dose bolus tirofiban, 6752 to abciximab, 1669 to eptifibatide, 16,500 to heparin, and 11,070 to bivalirudin. Mean age was 64±11years, 75% were male, 91% were treated with stenting, 71% with clopidogrel, and 74% for acute coronary syndrome. High-dose bolus tirofiban was associated with a significant reduction in all-cause mortality compared with heparin (OR 0.57 [credible intervals 0.37, 0.9]) and eptifibatide (OR 0.44 [credible intervals 0.19, 1.0]). GPI regimens had less myocardial infarction and major adverse cardiovascular events but greater bleeding compared with heparin and bivalirudin. There was no difference among the GPI therapies for other outcomes, including myocardial infarction, major adverse cardiovascular events, and major bleeding.

CONCLUSIONS

Our network meta-analysis of 38,645 patients demonstrated that GPI regimens were associated with a reduction in recurrent myocardial infarction or major adverse cardiovascular events for PCI, while bivalirudin was associated with the lowest risk of bleeding.

Safety and Efficacy of Bivalirudin in Patients With Diabetes Mellitus Undergoing Percutaneous Coronary Intervention: From the REPLACE-2, ACUITY and HORIZONS-AMI Trials

Optimal antithrombotic pharmacotherapy in patients affected by diabetes mellitus (DM) undergoing percutaneous coronary intervention is unclear. We sought to evaluate the safety and efficacy of bivalirudin compared with heparin plus a glycoprotein IIb/IIIa inhibitor (GPI) in patients with DM undergoing percutaneous coronary intervention. We pooled patient-level data from the Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events-2, Acute Catheterization and Urgent Intervention Triage strategy, and Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trials. The primary efficacy end point was the incidence of major adverse cardiac events, defined as the composite of death, myocardial infarction, or unplanned revascularization at 30 days. The primary safety end point was the incidence of 30-day non-coronary artery bypass graft-related major bleeding. All-cause mortality was reported at 30 days and 1 year. Of the 14,737 patients included in the pooled database, 3,641 (24.7%) had DM. Patients with DM had higher rates of 30-day major bleeding and 30-day and 1-year all-cause mortality. There were no differences in 30-day major adverse cardiac events between bivalirudin versus heparin plus GPI in patients with DM (6.9% vs 7.8%; relative risk [RR] 0.89, 95% CI 0.71 to 1.12) or without DM (7.5% vs 6.7%; RR 1.11, 95% CI 0.97 to 1.27; pinteraction = 0.10). Bivalirudin treatment was associated with reduced risk of major bleeding in similar magnitude in patients with DM (4.3% vs 6.6% RR 0.68, 95% CI 0.51 to 0.89) or without DM (3.2% vs 6.1%; RR 0.51, 95% CI 0.43 to 0.61; pinteraction = 0.15). The hemorrhagic benefit of bivalirudin was noted for both access site- and non-access site-related bleeding. Overall, bivalirudin treatment was associated with a significant 1-year mortality benefit (2.7% vs 3.3%; RR 0.82, 95% CI 0.68 to 0.98; p = 0.03), which was consistent between patients with or without DM (pinteraction = 0.30). In conclusion, compared with heparin plus GPI, bivalirudin was associated with similar 30-day antithrombotic efficacy and better 30-day freedom from bleeding and 1-year mortality, irrespective of diabetic status.

Impact of bivalirudin on post-procedural epicardial blood flow, risk of stent thrombosis and mortality after percutaneous coronary intervention

AIMS

We aimed to assess the association of bivalirudin with post-procedural Thrombolysis In Myocardial Infarction (TIMI) flow, acute (≤24 hours) and 30-day stent thrombosis (ST), and one-year mortality.

METHODS AND RESULTS

The study included 11,623 patients undergoing percutaneous coronary intervention (PCI). The primary outcomes were post-procedural TIMI flow grade ≤2 and definite acute ST. In groups treated with bivalirudin (n=3,135), abciximab plus unfractionated heparin (UFH; n=3,539) and UFH alone (n=4,949), post-procedural TIMI was ≤2 in 5.2%, 3.2% and 3.2% of patients, respectively (adjusted odds ratio [OR]=1.96 [95% confidence interval] 1.47-2.56 for bivalirudin versus abciximab plus UFH and OR=1.56 [1.20-2.04] for bivalirudin versus UFH). Definite acute ST occurred in two patients (0.06%) treated with bivalirudin, two patients (0.06%) treated with abciximab plus UFH, and seven patients (0.14%) treated with UFH (p=0.47). Bivalirudin was not associated with increased risk of 30-day ST (hazard ratio [HR]=1.20 [0.59-2.43] versus abciximab plus UHF, and HR=0.93 [0.48-1.82] versus UFH) or one-year mortality (HR=0.95 [0.70-1.28] versus abciximab plus UHF, and HR=1.05 [0.78-1.41] versus UFH).

CONCLUSIONS

Bivalirudin was associated with higher risk of suboptimal post-PCI TIMI flow but not with increased risk of acute or 30-day definite ST or one-year mortality compared with abciximab plus UFH or UFH alone.

Short- and long-term outcomes in diabetes patients undergoing percutaneous coronary intervention with bivalirudin compared with heparin and glycoprotein IIb/IIIA inhibitors: A meta-analysis of randomized trials

BACKGROUND

Diabetes patients undergoing percutaneous coronary intervention (PCI) have more complications than nondiabetes patients, including increased long-term mortality. Use of bivalirudin versus heparin and glycoprotein IIb/IIIa inhibitors (GPI) in diabetes patients undergoing PCI and its effect on long-term mortality were evaluated in few randomized trials, but with conflicting results.

METHODS

We searched the literature for randomized controlled trials that compared heparin and GPI therapy with bivalirudin in diabetes patients undergoing PCI. The incidence of major adverse cardiovascular events (MACE), death from any cause, myocardial infarction (MI), urgent revascularization, major and minor bleeding (at 30 days), as well as all-cause mortality at 1 year were included, and meta-analysis was performed.

RESULTS

A total of 5,137 patients with diabetes were included in four randomized trials. At 30 days, bivalirudin, compared with heparin and GPI, caused less major bleeding (odds ratio (OR), 0.68; 95% confidence interval (CI), 0.52-0.89; P = 0.005) and less minor bleeding (OR, 0.48; 95% CI, 0.41-0.57; P < 0.00001) and similar rates of MACE (OR, 0.87; 95% CI, 0.70-1.08; P = 0.21), MI (OR, 0.87; 95% CI, 0.68-1.10; P = 0.25), and urgent revascularization (OR, 1.12; 95% CI, 0.76-1.65; P = 0.57). Death from any cause at 30 day was numerically lower with bivalirudin use but not statistically significant (OR, 0.72; 95% CI, 0.46-1.13; P = 0.15). Mortality at 1 year was significantly lower in diabetes patients treated with bivalirudin compared with heparin and GPI (OR, 0.72; 95% CI, 0.52-0.99; P = 0.04). A secondary analysis suggests that the major bleeding benefit with bivalirudin may be driven by mandated use of GPI in heparin arm.

CONCLUSION

Among patients with diabetes undergoing PCI, bivalirudin caused less major and minor bleeding compared with heparin and GPI, with similar rates of MACE, death, MI, and urgent revascularization at 30 days, but significantly lower mortality rates at 1 year.

Current antiplatelet treatment strategy in patients with diabetes mellitus

Patients with diabetes mellitus (DM) have accelerated atherosclerosis with an increased risk for atherothrombotic cardiovascular complications. A state of high platelet reactivity and activation, hypercoagulability (prothrombotic state) and a subdued response to standard antiplatelet agents may explain high rate of adverse cardiovascular events in patients with DM. Several antithrombotic treatment strategies have been developed to control the prothrombotic state in patients with DM: dose modification of commonly used agents; use of potent agents; and addition of a third antithrombotic drug (triple therapy) to commonly prescribed dual antiplatelet therapy of aspirin and a P2Y12 inhibitor. The present review aims to provide an overview of the current knowledge on platelet abnormalities in patients with DM, focusing on the challenges and perspectives of antiplatelet treatment strategies in this population.

Platelet glycoprotein IIb/IIIa blockers during percutaneous coronary intervention and as the initial medical treatment of non-ST segment elevation acute coronary syndromes

BACKGROUND

During percutaneous coronary intervention (PCI), and in non-ST segment elevation acute coronary syndromes (NSTEACS), the risk of acute vessel occlusion by thrombosis is high. Glycoprotein IIb/IIIa blockers strongly inhibit platelet aggregation and may prevent mortality and myocardial infarction. This is an update of a Cochrane review first published in 2001, and previously updated in 2007 and 2010.

OBJECTIVES

To assess the efficacy and safety effects of glycoprotein IIb/IIIa blockers when administered during PCI, and as initial medical treatment in patients with NSTEACS.

SEARCH METHODS

We updated the searches of the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 12, 2012), MEDLINE (OVID, 1946 to January Week 1 2013) and EMBASE (OVID, 1947 to Week 1 2013) on 11 January 2013.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous IIb/IIIa blockers with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed trial quality and extracted data. We collected major bleeding as adverse effect information from the trials. We used odds ratios (OR) and 95% confidence intervals (CI) for effect measures.

MAIN RESULTS

Sixty trials involving 66,689 patients were included. During PCI (48 trials with 33,513 participants) glycoprotein IIb/IIIa blockers decreased all-cause mortality at 30 days (OR 0.79, 95% CI 0.64 to 0.97) but not at six months (OR 0.90, 95% CI 0.77 to 1.05). All-cause death or myocardial infarction was decreased both at 30 days (OR 0.66, 95% CI 0.60 to 0.72) and at six months (OR 0.75, 95% CI 0.64 to 0.86), although severe bleeding was increased (OR 1.39, 95% CI 1.21 to 1.61; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without acute coronary syndromes.As initial medical treatment of NSTEACS (12 trials with 33,176 participants), IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.90, 95% CI 0.79 to 1.02) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or myocardial infarction at 30 days (OR 0.91, 95% CI 0.85 to 0.98) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.29, 95% CI 1.14 to 1.45; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

When administered during PCI, intravenous glycoprotein IIb/IIIa blockers reduce the risk of all-cause death at 30 days but not at six months, and reduce the risk of death or myocardial infarction at 30 days and at six months, at a price of an increase in the risk of severe bleeding. The efficacy effects are homogeneous but are less marked in patients pre-treated with clopidogrel where they seem to be effective only in patients with acute coronary syndromes. When administered as initial medical treatment in patients with NSTEACS, these agents do not reduce mortality although they slightly reduce the risk of death or myocardial infarction.

Antiplatelet therapy in patients undergoing percutaneous coronary intervention: economic considerations

Percutaneous coronary intervention (PCI) is one of the most common medical procedures performed for treatment of coronary artery disease. Antiplatelet medications as adjunctive therapy for PCI are used routinely, with indications for specific agents or their combinations varying depending on the clinical scenario. While the cost-effectiveness of well-established agents has been extensively studied, newer drugs have not been evaluated as thoroughly. In addition, the clinical application of some antiplatelet drugs has recently changed, thus making older studies of cost effectiveness less applicable to the current landscape of clinical practice. This article reviews cost-effectiveness considerations of antiplatelet therapies in the treatment of coronary artery disease in patients undergoing PCI. Aspirin, P2Y12 inhibitors including clopidogrel and the newer agents prasugrel and ticagrelor, as well as glycoprotein (GP) IIb/IIIa inhibitors, are discussed. Overall, the use of dual antiplatelet therapy with aspirin and a P2Y12 inhibitor in patients undergoing PCI improves ischaemic outcomes and appears to be cost effective. The few available studies suggest that the recently approved medications prasugrel and ticagrelor are cost-effective alternatives to clopidogrel. However, no direct comparison between these two newer agents is available. The indications for GP IIb/IIIa inhibitors have changed in the current PCI era, and there is a paucity of cost-effectiveness data for their use in contemporary care.

Incidence and prognostic value of bleeding after percutaneous coronary intervention in patients older than 75 years of age

OBJECTIVES

We aimed to assess the impact of bleeding after percutaneous coronary intervention (PCI) on the outcome of patients >75 years of age.

BACKGROUND

Limited information exists on the impact of post-PCI bleeding on the outcome in elderly patients.

METHODS

This study included 3,255 patients >75 years of age. Bleeding events were assessed using the Bleeding Academic Research Consortium (BARC) criteria. The primary outcome was 1-year mortality.

RESULTS

Within 30 days after PCI, bleeding occurred in 501 patients (15.4%). Bleeding according to BARC was: class 1 (170 patients; 33.9%), class 2 (81 patients; 16.2%), class 3a (177 patients; 35.3%), class 3b (65 patients; 13.0%), class 3c (four patients; 0.8%), and class 4 (four patients; 0.8%). There were 201 deaths within the first year after PCI: 61 deaths (12.3%) among bleeders and 140 deaths (5.1%) among nonbleeders (adjusted hazard ratio = 2.03, 95% confidence interval [CI] 1.42-2.91, P < 0.001). Bleeding improved the discriminatory power of multivariable model for mortality prediction (P = 0.001). Female sex (adjusted odds ratio [OR] = 1.49 [1.17-1.88], P = 0.001) and reduced renal function (adjusted OR = 1.30 [1.04-1.63], P = 0.019 for each 30 ml/min decrease in the creatinine clearance) were independent associates of increased bleeding risk. Bivalirudin reduced the bleeding risk by 24% compared with unfractionated heparin and 33% compared with abciximab plus unfractionated heparin.

CONCLUSIONS

Post-PCI bleeding is an important prognostic factor in patients >75 years of age. The risk for bleeding in this age category is increased in women and patients with impaired renal function. Bleeding risk is reduced by bivalirudin.

Platelet glycoprotein IIb/IIIa blockers during percutaneous coronary intervention and as the initial medical treatment of non-ST segment elevation acute coronary syndromes

BACKGROUND

During percutaneous coronary intervention (PCI), and in non-ST segment elevation acute coronary syndromes (NSTEACS), the risk of acute vessel occlusion by thrombosis is high. Glycoprotein IIb/IIIa blockers strongly inhibit platelet aggregation and may prevent mortality and myocardial infarction. This is an update of a Cochrane review first published in 2001, and previously updated in 2007 and 2010.

OBJECTIVES

To assess the efficacy and safety effects of glycoprotein IIb/IIIa blockers when administered during PCI, and as initial medical treatment in patients with NSTEACS.

SEARCH METHODS

We updated the searches of the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 12, 2012), MEDLINE (OVID, 1946 to January Week 1 2013) and EMBASE (OVID, 1947 to Week 1 2013) on 11 January 2013.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous IIb/IIIa blockers with placebo or usual care.

DATA COLLECTION AND ANALYSIS

Two authors independently selected studies for inclusion, assessed trial quality and extracted data. We collected major bleeding as adverse effect information from the trials. We used odds ratios (OR) and 95% confidence intervals (CI) for effect measures.

MAIN RESULTS

Sixty trials involving 66,689 patients were included. During PCI (48 trials with 33,513 participants) glycoprotein IIb/IIIa blockers decreased all-cause mortality at 30 days (OR 0.79, 95% CI 0.64 to 0.97) but not at six months (OR 0.90, 95% CI 0.77 to 1.05). All-cause death or myocardial infarction was decreased both at 30 days (OR 0.66, 95% CI 0.60 to 0.72) and at six months (OR 0.75, 95% CI 0.64 to 0.86), although severe bleeding was increased (OR 1.39, 95% CI 1.21 to 1.61; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without acute coronary syndromes.As initial medical treatment of NSTEACS (12 trials with 33,176 participants), IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.90, 95% CI 0.79 to 1.02) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or myocardial infarction at 30 days (OR 0.91, 95% CI 0.85 to 0.98) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.29, 95% CI 1.14 to 1.45; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

When administered during PCI, intravenous glycoprotein IIb/IIIa blockers reduce the risk of all-cause death at 30 days but not at six months, and reduce the risk of death or myocardial infarction at 30 days and at six months, at a price of an increase in the risk of severe bleeding. The efficacy effects are homogeneous but are less marked in patients pre-treated with clopidogrel where they seem to be effective only in patients with acute coronary syndromes. When administered as initial medical treatment in patients with NSTEACS, these agents do not reduce mortality although they slightly reduce the risk of death or myocardial infarction.

Incidence and impact on prognosis of bleeding during percutaneous coronary interventions in patients with chronic kidney disease

BACKGROUND

Limited information exists on the prognostic impact of bleeding after percutaneous coronary intervention (PCI) in patients with chronic kidney disease (CKD). We investigated the impact of bleeding after PCI on the outcome of these patients.

METHODS

The study included 2,934 patients with estimated creatinine clearance <60 ml/min. Bleeding events within 30 days after PCI were assessed using the Bleeding Academic Research Consortium (BARC) criteria. The primary outcome was 1-year mortality.

RESULTS

Bleeding events occurred in 485 patients (16.5 %). BARC classes were: class 1 (n = 155), class 2 (n = 73), class 3a (n = 182), class 3b (n = 68), class 3c (n = 6) and class 4 (n = 1). There were 212 deaths over the first year after PCI: 60 deaths in patients who bled and 152 deaths in patients who did not bleed (Kaplan-Meier [KM] estimates, 12.5 and 6.3 %; odds ratio [OR] = 2.11, 95 % confidence interval [CI] 1.57-2.83, P < 0.001). Nonfatal myocardial infarction occurred in 71 patients who bled and in 141 patients who did not bleed (KM estimates, 14.8 and 5.8 %; OR = 2.70 [2.05-3.55], P < 0.001). After adjustment, bleeding was independently associated with increased risk of 1-year mortality (adjusted hazard ratio [HR] = 1.90 [1.33-2.72], P < 0.001) and myocardial infarction (adjusted HR = 2.74 [1.99-3.78], P < 0.001). Bleeding improved the discriminatory power of the multivariable model for prediction of mortality (absolute and relative integrated discrimination improvement [IDI], 0.011 and 15.4 %; P = 0.004) or myocardial infarction (absolute and relative IDI, 0.017 and 70.8 %; P < 0.001).

CONCLUSIONS

Peri-PCI bleeding in patients with CKD is independently associated with the increased risk of 1-year mortality and nonfatal myocardial infarction.

Synergistic effect of thrombus aspiration and abciximab in primary percutaneous coronary intervention

BACKGROUND

Previous studies failed to assess the individual prognostic role of thrombus aspiration (TA) or abciximab in primary percutaneous coronary intervention (pPCI), due their prevalent combined use.

METHODS AND RESULTS

A total of 644 consecutive ST-segment elevation myocardial infarction patients treated with pPCI were included in this retrospective registry from January 2006 to December 2008. Patients were divided in: (a) Group 1, with conventional pPCI; (b) Group 2, with pPCI and abciximab; (c) Group 3, with pPCI and TA; (d) Group 4, with pPCI and abciximab plus TA. Primary end point was the composite of major adverse cardiovascular events (MACEs, defined as overall mortality, myocardial infarction, target vessel revascularization, and major bleedings) at 1 year. Baseline clinical and angiographic characteristics were not different among the groups, with the exception of a younger age in group 4. The two groups of patients treated with TA (group 3 and 4) received more frequently direct stenting (P < 0.001 vs. group 1 for both), presented higher rate of end-procedural TIMI flow grade 3 (P < 0.001 vs. group 1 for both), and lower rate of no-reflow (P = 0.016 and P < 0.001 vs. group 1, respectively). Patients of group 2 presented a borderline nonsignificant trend toward higher rate of end-procedural TIMI flow grade 3 (P = 0.083 vs. group 1). MACEs at 1 year were 43 (29%) in group 1 versus 25 (22%) in group 2 versus 24 (19%) in group 3 versus 32 (13%) in group 4 (log-rank P = 0.001). At the multivariate Cox regression analysis, combined TA plus abciximab in group 4 [hazard ratio (HR): 0.48, confidence interval (CI) 95% 0.28-0.84, P = 0.01] and a higher left ventricular ejection fraction (HR: 0.97, CI 95% 0.95-0.98, P < 0.001) were significantly associated with lower MACE rate.

CONCLUSIONS

The combination of pharmacologic and mechanic antithrombotic treatment during pPCI was associated with better 1-year clinical outcome.

The association of diabetes mellitus with clinical outcomes after coronary stenting: a meta-analysis

Background

Previous studies have shown inconsistent results on the association between diabetes mellitus (DM) and some clinical outcomes. We conducted a meta-analysis of observational studies to assess effect of DM on clinical outcomes after coronary stenting.

Methods

We searched for studies without language restriction in PubMed, Embase and Cochrane library prior to 2012. The clinical outcomes including in-stent restenosis (ISR), major adverse cardiac events (MACE), stent thrombosis (ST), target lesion revascularization (TLR) and target vessel revascularization (TVR). Adjusted odds ratio (OR), and the corresponding 95% confidence interval (95% CI) was summarized.

Results

55 studies involving 128,084 total patients (38,416 DM patients and 89,668 controls) were eligible for our analysis. Overall, there were significant associations between DM and ISR (OR = 1.70, 95% CI: 1.53–1.89, I² = 0.0%), MACE (OR = 1.54, 95% CI: 1.36–1.73, I² = 29.0%), ST (OR = 2.01, 95% CI: 1.36–2.97, I² = 47.7%), TLR (OR = 1.46, 95% CI: 1.26–1.68, I² = 43.3%) as well as TVR (OR = 1.33, 95% CI: 1.17–1.51, I² = 48.3). Subgroup analysis showed that the associations were similar between BMS and DES implantation. Moreover, there was no significant association in the ST subgroup after 1–3 years follow-up.

Conclusions

Our meta-analysis suggests that after coronary stent implantation, DM is associated with ISR, MACE, ST, TLR and TVR. DM appears to be a vital risk factor of these clinical outcomes.

Bleeding after percutaneous coronary intervention in women and men matched for age, body mass index, and type of antithrombotic therapy

BACKGROUND

Factors underlying the increased risk of bleeding after percutaneous coronary intervention (PCI) in women compared with men remain incompletely understood.

METHODS

The study included 3,351 women and 3,351 men matched for age, body mass index, and type of antithrombotic therapy. Bleeding within the 30 days after PCI was defined using the Bleeding Academic Research Consortium criteria. The main outcome was 1-year mortality.

RESULTS

Bleeding occurred in 518 women and 354 men (15.5% vs 10.6%, odds ratio [OR] 1.55, 95% CI 1.34-1.79, P < .001). Severe (Bleeding Academic Research Consortium class ≥2) bleeds (9.4% vs 6.5%, P < .001) and access site bleeds (10.1% vs 5.4%, P < .001) were more common in women. After adjustment, female sex remained an independent correlate of any bleeding (adjusted OR 1.61 [1.35-1.92], P < .001) and access site (adjusted OR 2.00 [1.59-2.50], P < .001) but not of nonaccess site (adjusted OR 1.18 [0.91-1.54], P = .205) bleeding. There were 248 deaths: 32 deaths among men with bleeding versus 107 deaths among men with no bleeding (9.1% vs 3.6%, OR 2.68 [1.78-4.05], P < .001) and 40 deaths among women with bleeding vs 69 deaths among women with no bleeding (7.8% vs 2.5%, OR 3.35 [2.24-5.01], P < .001). No difference in mortality was observed among women and men who bled (P = .487). Bleeding was independently associated 1-year mortality (adjusted hazard ratio 2.18 [1.68-2.84], P < .001) with no bleeding-by-sex interaction (P = .439).

CONCLUSIONS

Despite matching for age, body mass index, and type of antithrombotic therapy, bleeding risk after PCI remained significantly higher in women than in men. Bleeding was associated with increased risk of 1-year mortality with no bleeding-by-sex interaction.

Update on platelet glycoprotein IIb/IIIa inhibitors: recommendations for clinical practice

Antiplatelet therapy is the cornerstone of treatment for patients with acute coronary syndrome (ACS) and undergoing percutaneous coronary intervention (PCI). Glycoprotein IIb/IIIa receptors mediate platelet aggregation, representing the final common pathway of platelet-mediated thrombosis. Therefore, agents blocking this pathway may be desirable for the treatment of patients with ACS and PCI. Glycoprotein IIb/IIIa receptor inhibitors have been widely investigated and have been key to the pharmacological advancements in the field. However, although GPIs have been important to reduce ischemic complications, their elevated risk of bleeding complications remains a major limitation. The poor prognostic implications, including increased mortality, associated with bleeding complication underscores the need for alternative treatment options. Over the past years there have been several advancements in antithrombotic pharmacology which have led to changes in recommendations for GPI usage in clinical practice. This is an overview of the most recent clinical trial data on GPIs, and provides practical insight on their modern day use in ACS therapy.

Optimal choice of coronary revascularization and stent type in diabetic patients with coronary artery disease

Patients with diabetes mellitus (DM) are prone to a diffuse and accelerated form of coronary artery disease (CAD), which in turn is a major cause of cardiac-related morbidity and mortality. Compared with patients without diabetes, patients with diabetes undergoing coronary revascularization are at higher risk of procedural, short-, and long-term cardiovascular events and mortality. Although coronary artery bypass grafting (CABG) has been regarded as the primary revascularization strategy in diabetic patients with complex CAD, percutaneous coronary intervention (PCI) is an effective revascularization alternative, due to remarkable advances in stent devices and adjunctive drug therapies. Outcomes data, from subgroup analyses and small-sized clinical trials and large registries, have suggested that PCI with current stent technology showed comparable long-term risks of mortality and hard endpoints, but higher risk of repeat revascularization for the diabetic population compared to CABG. However, the recent landmark International Future REvascularization Evaluation in patients with diabetes mellitus: optimal management of Multivessel disease (FREEDOM) trial provides compelling evidence of the superiority of CABG over PCI in reducing the rates of death, myocardial infarction, at the expense of stroke, in patients with diabetes with advanced CAD. When opting for PCI in patients with diabetes, currently used drug-eluting stents (DES) are more efficient in reducing the risk of repeat revascularization without compromising safety outcomes, compared to bare-metal stents. The selection of a specific type of DES in patients with diabetes is controversial and therefore more data comparing second- and newer-generation DES for patients with diabetes are currently needed. Also, efforts to make more advanced DES platforms suitable for patients with diabetes with complicated angiographic features are still ongoing.

Implementation of standardized assessment and reporting of myocardial infarction in contemporary randomized controlled trials: a systematic review

Myocardial infarction (MI) is a key endpoint in randomized controlled trials (RCTs), but heterogeneous definitions limit comparisons across RCTs or meta-analyses. The 2000 European Society of Cardiology/American College of Cardiology MI redefinition and the 2007 universal MI definition consensus documents made recommendations to address this issue. In cardiovascular randomized trials, we evaluated the impact of implementation of three key recommendations from these reports-troponin use to define MI; separate reporting of spontaneous and procedure-related MI; and infarct size reporting. We searched ClinicalTrials.gov and MEDLINE databases for cardiovascular RCTs with more than 500 patients in which enrolment began between September 2000 and July 2012 and that listed MI in the primary endpoint. We searched English-language publications with primary results or design papers. Of 3222 studies screened, 96 (3.0%) met our criteria. We extracted enrolment start date, number of patients and MI events, follow-up duration, and coronary revascularization rate. Data extraction quality was assessed by duplicated extractions. Of 96 RCTs, 80 had a primary results publication, comprising 608 091 patients and 43 621 endpoint MIs. Myocardial infarction represented 45.3% (95% confidence interval, 40.2-50.4) of events in the primary composite endpoint. Troponin defined MI in 57% (53/93) of trials with an MI definition available. Of these RCTs, three used troponin only if creatine kinase-MB was unavailable, six used troponin to define peri-procedural MI, seven specified the 99th percentile as the MI decision limit, and three reported spontaneous and procedure-related MI separately. None reported biomarker-based infarct size, but five reported MI as multiples of the assay upper limit of normal. Although MI is a major component of cardiovascular RCT primary endpoints, standardized MI reporting and implementation of consensus document recommendations for MI definition are limited. Developing appropriate strategies for uniform implementation is required.

Effect of tailored antiplatelet therapy on periprocedural myonecrosis in patients with diabetes mellitus (from the DM-Verify Now Trial)

We investigated whether additional platelet inhibition with a glycoprotein IIb/IIIa inhibitor would be beneficial in reducing the risk of periprocedural myocardial infarction (PMI) in diabetic patients with high residual platelet reactivity (HPR). Patients with diabetes mellitus were administered aspirin and clopidogrel at a 300-mg loading dose 1 day before the procedure, and the VerifyNow P2Y(12) assay was performed just before percutaneous coronary intervention. Patients with HPR, defined as a P2Y(12) reaction unit of ≥270 were randomly assigned to group A or control group C1. Patients without HPR were assigned to control group C2. Conventional anticoagulation with heparin was given to groups C1 and C2, and group A received additional abciximab treatment. Clinically relevant PMI was defined as any elevation in the biomarkers creatine kinase-MB isoenzyme and cardiac troponin I >3 times the upper normal limit measured 8, 16, or 24 hours after percutaneous coronary intervention. Of the patients, 47 and 51 were assigned to group A and C1; the clinical and procedural characteristics in the 2 groups were balanced. Of the 47 patients in group A and 51 patients in group C1, 9 (19%) and 9 (18%), respectively, experienced a PMI event according to the creatine kinase-MB cutoff (p = 1.00), and 27 in group A (57%) and 29 in group C1 (57%) experienced a PMI event according to the troponin I cutoff (p = 1.00). Five minor bleeding events, including small and localized hematomas, were observed immediately after the procedure (4 in group A and 1 in group C1). Only 1 major bleeding event, retroperitoneal hemorrhage, was observed in group A. The patients in group C2 had a PMI event rate (50% of 32 patients, p = 1.00) similar to that of group C1. In conclusion, additional platelet inhibition using a tailored approach and a point-of-care assay did not improve the periprocedural outcome in diabetic patients with HPR.

Acute coronary syndrome in patients with diabetes mellitus: perspectives of an interventional cardiologist

Diabetes mellitus (DM) is well known to be a coronary artery disease risk equivalent but the cellular mechanism is not completely understood. Recently, virtual histology intravascular ultrasound has demonstrated that patients with DM tend to have a higher occurrence of vulnerable plaques as compared with patients without DM. Insulin-sensitizing agents, such as metformin, have been shown to have limited cardioprotective effects, whereas thiazolidinediones, such as rosiglitazone, have been reported to have possible deleterious effects on cardiovascular mortality in a meta-analysis; however, limited data exist. In contrast, pioglitazone has been reported to have a significant benefit in patients with type 2 DM with acute coronary syndrome (ACS). Animal and human studies have demonstrated the myocardial protective effects of incretins and hold promise in reducing the incidence of major adverse cardiac events in patients with DM. Moreover, in addition to aspirin, the early use of potent antiplatelet agents, such as prasugrel and intravenous glycoprotein IIb-IIIa inhibitors, in patients with DM presenting with ACS is crucial for reducing cardiovascular events in most patients. Thus, patients with DM deserve special attention in global risk factor reduction and development of newer therapeutic agents to improve glycemic control while minimizing or reducing cardiovascular events. This article focuses on ACS in patients with DM, the pathophysiology of "vulnerable blood" in patients with DM, and newer treatment strategies to improve outcomes in this high-risk patient population.

Stenting in Acute STEMI Intervention

Stenting in acute myocardial infarction (AMI) has the benefits of achieving acute optimal angiographic results and correcting residual dissection to decrease the incidence of restenosis and reocclusion. Studies have shown that percutaneous transluminal coronary angioplasty for primary treatment after AMI is superior to thrombolytic therapy regarding the restoration of normal coronary blood flow. Coronary stenting improves initial success rates, decreases the incidence of abrupt closure, and is associated with a reduced rate of restenosis. In the presence of thrombus-containing lesions, coronary stenting constitutes an effective therapeutic strategy, either after failure of initial angioplasty or electively as the primary procedure.

Different impact of diabetes mellitus on in-hospital and 1-year mortality in patients with acute myocardial infarction who underwent successful percutaneous coronary intervention: results from the Korean Acute Myocardial Infarction Registry

BACKGROUND/AIMS

The aim of this study was to evaluate the impact of diabetes mellitus (DM) on in-hospital and 1-year mortality in patients who suffered acute myocardial infarction (AMI) and underwent successful percutaneous coronary intervention (PCI).

METHODS

Among 5,074 consecutive patients from the Korea AMI Registry with successful revascularization between November 2005 and June 2007, 1,412 patients had a history of DM.

RESULTS

The DM group had a higher mean age prevalence of history of hypertension, dyslipidemia, ischemic heart disease, high Killip class, and diagnoses as non-ST elevation MI than the non-DM group. Left ventricular ejection fraction (LVEF) and creatinine clearance were lower in the DM group, which also had a significantly higher incidence of in-hospital and 1-year mortality of hospital survivors (4.6% vs. 2.8%, p = 0.002; 5.0% vs. 2.5%, p < 0.001). A multivariate analysis revealed that independent predictors of in-hospital mortality were Killip class IV or III at admission, use of angiotensin converting enzyme inhibitors or angiotensin-II receptor blockers, LVEF, creatinine clearance, and a diagnosis of ST-elevated MI but not DM. However, a multivariate Cox regression analysis showed that DM was an independent predictor of 1-year mortality (hazard ratio, 1.504; 95% confidence interval, 1.032 to 2.191).

CONCLUSIONS

DM has a higher association with 1-year mortality than in-hospital mortality in patients with AMI who underwent successful PCI. Therefore, even when patients with AMI and DM undergo successful PCI, they may require further intensive treatment and continuous attention.

Antiplatelet drugs: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

The article describes the mechanisms of action, pharmacokinetics, and pharmacodynamics of aspirin, dipyridamole, cilostazol, the thienopyridines, and the glycoprotein IIb/IIIa antagonists. The relationships among dose, efficacy, and safety are discussed along with a mechanistic overview of results of randomized clinical trials. The article does not provide specific management recommendations but highlights important practical aspects of antiplatelet therapy, including optimal dosing, the variable balance between benefits and risks when antiplatelet therapies are used alone or in combination with other antiplatelet drugs in different clinical settings, and the implications of persistently high platelet reactivity despite such treatment.

Validation of the Bleeding Academic Research Consortium Definition of Bleeding in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Background—

The Bleeding Academic Research Consortium (BARC) has recently proposed a unified definition of bleeding in patients receiving antithrombotic therapy. We investigated the relationship between bleeding events as defined by BARC and 1-year mortality in patients undergoing percutaneous coronary intervention (PCI) and assessed whether the BARC bleeding definition is superior to existing bleeding definitions in regard to mortality prediction in patients after PCI procedures.

Methods and Results—

This study represents a patient-level pooled analysis of 12 459 patients recruited in 6 randomized trials of patients undergoing PCI. Bleeding events were assessed with the use of BARC, Thrombolysis in Myocardial Infarction (TIMI), and Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) trial criteria. The primary outcome was 1-year mortality. Bleeding occurred in 1233 patients (9.9%) according to BARC (679 patients or 5.4% with BARC class ≥2 bleeding), in 374 patients (3.0%) according to TIMI, and in 491 patients (3.9%) according to REPLACE-2 criteria. There were 340 deaths (2.7%) over the first year after PCI. BARC class ≥2 bleeding was associated with a significant increase in 1-year mortality (adjusted hazard ratio 2.72; 95% confidence interval, 2.03–3.63). The predictivity of a multivariable model for 1-year mortality was significantly improved after inclusion of bleeding defined according to BARC to an extent comparable to that provided by TIMI and REPLACE-2 criteria.

Conclusions—

The present study demonstrated a close association between bleeding events defined according to BARC and 1-year mortality after PCI.

Contemporary use of glycoprotein IIb/IIIa inhibitors

Platelet glycoprotein IIb/IIIa inhibitors (GPI) are antithrombotic agents preventing the binding of fibrinogen to GP IIb/IIIa receptors. Thus, GPI interfere with interplatelet bridging mediated by fibrinogen. Currently, three generic GPI with different antithrombotic properties are available for intravenous administration: abciximab, eptifibatide, and tirofiban. The development of oral GPI was abandoned, whereas intravenous GPI were introduced in various clinical settings during the 1990s, yielding substantial benefit in the treatment of acute coronary syndromes, particularly during percutaneous coronary interventions. Results of the many randomised trials evidenced the efficacy of this drug class, though these trials were conducted prior to the emergence of modern oral antiplatelet therapy with efficient P2Y(12) inhibitors. Subsequent trials failed to consolidate the strongly favourable impression of GPI, and indications for their use have been more restricted in recent years. Nonetheless, GPI may still be beneficial during coronary interventions among high-risk patients including acute ST-elevation and non-ST-elevation myocardial infarctions, particularly in the absence of adequate pretreatment with oral antiplatelet drugs or when direct thrombin inhibitors are not utilised. Intracoronary GPI administration has been suggested as adjunctive therapy during primary percutaneous coronary intervention, and the results of larger ongoing trials are expected to elucidate its clinical potential. The present review outlines the key milestones of GPI development and provides an up-to-date overview of the clinical applicability of these drugs in the era of refined coronary stenting, potent antithrombotic drugs, and novel thrombin inhibiting agents.

Optimal use of platelet glycoprotein IIb/IIIa receptor antagonists in patients undergoing percutaneous coronary interventions

Discovery of the central role of platelets in the pathogenesis of acute coronary syndromes (ACS) and ischaemic complications of percutaneous coronary interventions (PCI) has led to the widespread use of oral and parenteral platelet inhibitors to treat these conditions. Glycoprotein (GP) IIb/IIIa (also known as α(IIb)β(3)) receptors on the surface of platelets play an essential role in platelet aggregation and serve as a key mediator in the formation of arterial thrombus. When activated, GP IIb/IIIa receptors bind to fibrinogen, which serves as the 'final common pathway' in platelet aggregation. Of the numerous agents developed for modulating platelet activity, intravenous platelet GP IIb/IIIa receptor antagonists are the most potent. There are four agents in clinical use, including abciximab, eptifibatide, tirofiban and lamifiban, although lamifiban is not approved for use in the US. While all agents block fibrinogen binding to GP IIb/IIIa, they do so by different mechanisms. Abciximab is a humanized form of a murine monoclonal antibody directed against GP IIb/IIIa, eptifibatide is a synthetic, cyclic heptapeptide that contains a lysine-glycine-aspartic acid (KGD) sequence that mimics the arginine-glycine-aspartic acid (RGD) sequence found on GP IIb/IIIa, tirofiban is a non-peptide antagonist derived by optimization of the tyrosine analogue that structurally mimicks the RGD-containing loop of the disintegrin echistatin, and lamifiban is a synthetic, non-cyclic, non-peptide, low-molecular-weight compound. In clinical trials, use of these agents reduces ischaemic adverse cardiovascular events in patients with ACS undergoing PCI, but at a cost of increased bleeding.