Optimizing the percutaneous interventional outcomes for patients with diabetes mellitus: results of the EPISTENT (Evaluation of platelet IIb/IIIa inhibitor for stenting trial) diabetic substudy

Treatment and Care of Patients with ST-Segment Elevation Myocardial Infarction-What Challenges Remain after Three Decades of Primary Percutaneous Coronary Intervention?

Primary percutaneous coronary intervention (pPCI) has revolutionized the prognosis of ST-segment elevation myocardial infarction (STEMI) and is the gold standard treatment. As a result of its success, the number of pPCI centres has expanded worldwide. Despite decades of advancements, clinical outcomes in STEMI patients have plateaued. Out-of-hospital cardiac arrest and cardiogenic shock remain a major cause of high in-hospital mortality, whilst the growing burden of heart failure in long-term STEMI survivors presents a growing problem. Many elements aiming to optimize STEMI treatment are still subject to debate or lack sufficient evidence. This review provides an overview of the most contentious current issues in pPCI in STEMI patients, with an emphasis on unresolved questions and persistent challenges.

Acute coronary syndromes in diabetic patients, outcome, revascularization, and antithrombotic therapy

Diabetes exacerbates the progression of atherosclerosis and is associated with increased risk of developing acute coronary syndrome (ACS). Approximatively 25-30% of patients admitted for ACS have diabetes. ACS occurs earlier in diabetics and is associated with increased mortality and a higher risk of recurrent ischemic events. An increased proinflammatory and prothrombotic state is involved in the poorer outcomes of diabetic patients. In the past decade advancement in both percutaneous coronary intervention (PCI) and coronary artery by-pass graft (CABG) techniques and more potent antiplatelet drugs like prasugrel and ticagrelor improved outcomes of diabetic patients with ACS, but this population still experiences worse outcomes compared to non-diabetic patients. While in ST elevation myocardial infarction urgent PCI is the method of choice for revascularization, in patients with non-ST elevation ACS an early invasive approach is suggested by the guidelines, but in the setting of multivessel (MV) or complex coronary artery disease (CAD) the revascularization strategy is less clear. This review describes the accumulating evidence regarding factors involved in promoting increased incidence and poor prognosis of ACS in patients with diabetes, the evolution over time of prognosis and outcomes, revascularization strategies and antithrombotic therapy studied until now.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Influence of integrins on thrombus formation: a road leading to the unravelling of DVT

Integrins are a group of transmembrane glycoprotein receptors that are responsible for platelet activation through bidirectional signalling. These receptors have left their footprints in various cellular events and have intrigued many groups of scientists that have led to some significant discoveries. A lot of the recent understanding of haemostasis has been possible due to the integrins filling the gaps in between several cellular mechanism. Apart from this, other important functions carried out by integrins are growth and maturation of cardiomyocytes, mechano-transduction, and interaction with actin cytoskeleton. The signalling cascade for integrin activation involves certain intracellular interacting proteins, which initiates the step-by-step activation procedure through 'inside-out' signalling. The signalling cascade gets activated through 'outside-in' signalling with the involvement of agonists such as ADP, Fibronectin, Vitronectin, and so on. This is a crucial step for the downstream processes of platelet spreading, followed by aggregation, clot progression and finally thrombus formation. Researchers throughout the world have shown direct relation of integrins with CVD and cardiac remodelling. The present review aims to summarize the information available so far on the involvement of integrins in thrombosis and its relationship to DVT. This information could be a bedrock of hidden answers to several questions on pathogenesis of deep vein thrombosis.

An anti-αVβ3 antibody inhibits coronary artery atherosclerosis in diabetic pigs

BACKGROUND AND AIMS

Diabetes is a major risk factor for the development of atherosclerosis. Hyperglycemia stimulates vascular smooth muscle cells (VSMC) to secrete ligands that bind to the αVβ3 integrin, a receptor that regulates VSMC proliferation and migration. This study determined whether an antibody that had previously been shown to block αVβ3 activation and to inhibit VSMC proliferation and migration in vitro, inhibited the development of atherosclerosis in diabetic pigs.

METHODS

Twenty diabetic pigs were maintained on a high fat diet for 22 weeks. Ten received injections of anti-β3 F(ab)₂ and ten received control F(ab)₂ for 18 weeks.

RESULTS

The active antibody group showed reduction of atherosclerosis of 91 ± 9% in the left main, 71 ± 11%, in left anterior descending, 80 ± 10.2% in circumflex, and 76 ± 25% in right coronary artery, (p < 0.01 compared to lesions areas from corresponding control treated arteries). There were significant reductions in both cell number and extracellular matrix. Histologic analysis showed neointimal hyperplasia with macrophage infiltration, calcifications and cholesterol clefts. Antibody treatment significantly reduced number of macrophages contained within lesions, suggesting that this change contributed to the decrease in lesion cellularity. Analysis of the biochemical changes within the femoral arteries that received the active antibody showed a 46 ± 12% (p < 0.05) reduction in the tyrosine phosphorylation of the β3 subunit of αVβ3 and a 40 ± 14% (p < 0.05) reduction in MAP kinase activation.

CONCLUSIONS

Blocking ligand binding to the αVβ3 integrin inhibits its activation and attenuates increased VSMC proliferation that is induced by chronic hyperglycemia. These changes result in significant decreases in atherosclerotic lesion size in the coronary arteries. The results suggest that this approach may have efficacy in treating the proliferative phase of atherosclerosis in patients with diabetes.

Review: The pathogenesis of type 2 diabetes and cardiovascular disease

Type 2 diabetes mellitus is increasing in prevalence, and is a potent risk factor for the development of atherosclerotic vascular disease and increased risk of adverse cardiovascular events. Approximately 15—25% of patients presenting with ischaemic heart disease have a history of diabetes mellitus. This cohort of patients continues to be at heightened short and long-term risk. This review highlights the many proposed biological drivers that likely play a deterministic role in the cardiovascular outcome of patients with type 2 diabetes mellitus.

Evidence Based Coagulation Monitors: Heparin Monitoring, Thromboelastography, and Platelet Function

The hemostatic management of patients undergoing cardiac surgery is a unique challenge. Since its inception, cardiopulmonary bypass (CPB) has required meticulous attention to maintaining adequate anticoagulation. New anticoagulants and alternative monitoring techniques present an opportunity to investigate potential advances in the area of anticoagulation for CPB. Hemostasis after CPB is still a vexing problem, and the addition of antiplatelet medication to the platelet defect already incurred during CPB has led to hemorrhagic complications in cardiac surgery. The two opposing processes of anticoagulation and hemostasis must be managed carefully and modified with respect to the patient's hematologic status and desired hemostatic outcome. Cardiac surgical patients consume a much larger fraction of perioperative blood transfusions than the percentage of the surgical population they represent. Thus, during CPB, careful attention must be paid to optimal anticoagulation, platelet quiescence, biocompatible circuitry and interventions, and to monitoring hemostasis. The multifactorial etiology of the CPB-induced hemostatic defect requires a multimodal approach to blood conservation and hemostasis monitoring, including heparin maintenance and sophisticated point-of-care hemostasis monitoring. Each technology has its own attributes and each may be suitable for different populations based upon the expected defects being measured. This article reviews the evidence supporting the use of point-of-care monitors in coagulation and hemostasis management in cardiac surgical patients.

Drug Eluting Stent Technology

The authors discuss the mechanism of action, clinical trial data, and economic impact of both the paclitaxel and sirolimus drug eluting stents (DESs). Both DESs have been approved by the Food and Drug Administration for the treatment of native coronary arteries to prevent in-stent restenosis (ISR), which patients have experienced since the advent of balloon angioplasty and the bare metal stent. In-stent restenosis, which manifests itself as ischemic symptoms in patients, occurs as a result of the healing process after stent implantation. Until now, there has not been an effective method to prevent ISR. The sirolimus and paclitaxel DESs elute agents that act locally by different mechanisms to reduce neointimal hyperplasia, which is primarily responsible for ISR. Both DESs are capable of reducing the rate of ISR. There are certain physical and mechanistic differences between the 2 stents; the stents have not been compared head to head. Currently, they are indicated for uncomplicated native coronary lesions. Further investigation is needed to define their roles in the treatment of more complex lesions.

Revascularization strategies in patients with Type 2 diabetes mellitus

This review aims to describe new developments in coronary revascularization strategies for patients with pre-existing Type 2 diabetes mellitus (DM). Recommended strategies for revascularization have been an active area of study with recent important developments. In patients with Type 2 DM and multivessel coronary artery disease (CAD), coronary artery bypass graft (CABG) surgery is the preferred method for revascularization. Patients with DM are at increased risk for diffuse cardiovascular disease due to the proinflammatory, prothrombotic effects of chronic hyperglycemia. In patients undergoing percutaneous coronary intervention, drug-eluting stents and more potent antiplatelet agents especially in those presenting with acute coronary syndromes should be employed.

CARBOHYDRATE METABOLISM DISORDERS AND CORONARY HEART DISEASE: PROGNOSTIC VALUE AND REVASCULARISATION EFFECTIVENESS

This literature review presents the data on the prevalence and prognostic value of carbohydrate metabolism disorders, such as Type 2 diabetes mellitus (DM) and pre-diabetes — fasting hyperglycaemia and impaired glucose tolerance), among patients with coronary heart disease (CHD). The authors present the results of large studies on comparative effectiveness of modern pharmacological treatment and myocardial revascularisation (percutaneous coronary intervention and coronary artery bypass graft surgery) in patients with CHD and DM. 

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.

Diabetes mellitus and acute coronary syndrome: lessons from randomized clinical trials

Diabetes mellitus is a major independent risk factor for acute coronary syndrome (ACS). In addition, diabetic patients with ACS suffer from increased mortality compared to their nondiabetic peers. Driven by multiple pathophysiological disturbances, such patients are predisposed to a proinflammatory, prothrombotic state, which may lead to plaque rupture. To counteract this more complex biology, several therapies and strategies have emerged, with some having unique preferential benefits in this population. Antiplatelet agents such as aspirin and clopidogrel have long been standard of care. Dose adjustment of these therapies remains the subject of continued research. Along with medical therapy, ACS diabetic patients preferentially benefit from primary percutaneous intervention compared to fibrinolysis. However, with advances in reperfusion techniques, the optimal strategy has yet to be determined. With these differences in ACS treatment responses, diabetic individuals may not just be a high-risk group, but may actually constitute a fundamentally different population, requiring dedicated clinical trials and individualized treatment regimens.

Impact of diabetes mellitus on the safety and effectiveness of bivalirudin in patients with acute myocardial infarction undergoing primary angioplasty: analysis from the HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial

OBJECTIVES

We sought to evaluate the safety and efficacy of bivalirudin compared with glycoprotein IIb/IIIa inhibitors (GPI) in diabetic patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

BACKGROUND

Prior studies have demonstrated that GPI are especially beneficial in patients with diabetes with acute coronary syndromes and/or those undergoing PCI.

METHODS

In the multicenter, prospective HORIZONS-AMI (Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction) trial, 3,602 patients with STEMI were randomized to bivalirudin or unfractionated heparin plus a GPI. Clinical outcomes were analyzed at 30 days and 1 year in patients with diabetes.

RESULTS

Diabetes mellitus was present in 593 patients (16.5%). The rates of cardiac death were significantly lower in diabetic patients treated with bivalirudin compared with heparin plus GPI (30 days: 2.1% vs. 5.5%, p = 0.04; 1 year: 2.5% vs. 7.1%, p = 0.01), and bivalirudin resulted in lower 30-day rates of stroke (0% vs. 2%, p = 0.02). There were no significant differences among diabetic patients randomized to bivalirudin versus heparin plus GPI in the 1-year rates of major adverse cardiac events (14.2% vs. 16.2%, p = 0.44), major bleeding (8.7% vs. 10.7%, p = 0.42), or stent thrombosis (4.2% vs. 3.8%, p = 0.85). By interaction testing, the relative effects of bivalirudin compared with heparin plus GPI were not significantly different in patients with and without diabetes.

CONCLUSIONS

In patients with diabetes mellitus presenting with STEMI undergoing primary PCI, anticoagulant therapy with bivalirudin compared with heparin plus GPI is safe and effective and might reduce cardiac mortality at 30 days and 1 year. (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).

The Role of Glycoprotein IIb/IIIa Inhibitors- A Promise Not Kept?

For over one decade Glycoproteins IIb/IIIa inhibitors (GPI) have been administered to prevent coronary artery thrombosis. Initially these agents were used for acute coronary syndromes and subsequently as adjunctive pharmacotherapy for percutaneous coronary interventions (PCIs).

Most benefit of GPI emerged from reduction of ischemic events: mostly non-q-wave myocardial infarctions (NQWMIs) during PCI. However, individual randomized clinical trials could not demonstrate that any of these agents could significantly reduce mortality in any clinical subset of patients. Studies of employing prolonged oral GPI administration resulted in excessive death. The non-homogenous statistically-significant reduction of ischemic endpoints was accompanied by an excess of bleeding, vascular complications, and thrombocytopenia. The clinical and ecomomic burden of major bleeding and thrombocytopenia is substantial. The ACUITY trial has initiate a new debate regarding the efficacy and safety of GPI.

Selective “patient-tailored” use of GPI limited to moderate-high risk PCI patients with low bleeding propensity is suggested. Research of new algorithms emphasizing abbreviated GPI administration, careful access site and bleeding surveillance, in conjunction with lower doses of unfractionated heparin or new and safer anti-thrombins may further enhance patient safety.

Platelet response to clopidogrel and restenosis in patients treated predominantly with drug-eluting stents

BACKGROUND

Preclinical studies suggest a relationship between early thrombotic response after vascular injury and later development of restenosis. The aim of this study was to assess the impact of platelet response to clopidogrel on the risk of restenosis after drug-eluting stenting (DES).

METHODS

A total of 1,608 consecutive patients were previously enrolled in a study on the relation between platelet reactivity and outcomes after DES. All patients received a loading dose of 600 mg clopidogrel. Blood samples for the assessment of adenosine diphosphate-induced platelet aggregation with multiple electrode platelet aggregometry were drawn directly before percutaneous coronary intervention. Clopidogrel low response was defined as upper quintile of multiple electrode platelet aggregometry measurements. Accordingly, 323 patients (20%) were considered as low and 1,285 (80%) as normal responders. Primary end point of the present study was target lesion revascularization at 1 year. Secondary end points included binary angiographic restenosis and late lumen loss at 6- to 8-month angiography.

RESULTS

Target lesion revascularization rates were comparable in both groups (10.9% vs 9.5%, hazard rate [HR] 1.2, 95% CI 0.8-1.7, P = .441). Follow-up angiography revealed no difference in binary angiographic restenosis (13.9% vs 15.9%, P = .445) and late lumen loss (0.32 +/- 0.64 vs 0.35 +/- 0.63 mm, P = .477). Low responders had significantly more stent thromboses (2.5% vs 0.5%, HR 5.4, 95% CI 1.9-15.6, P = .002), Q wave myocardial infarctions (2.5% vs 0.6%, HR 4.0, 95% CI 1.5-10.7, P = .005), and ischemic strokes (1.3% vs 0.2%, HR 5.4, 95% CI 1.2-24.0, P = .028) at 1 year.

CONCLUSION

Low platelet responsiveness to clopidogrel, a known predictor of thrombotic complications, does not have a significant impact on restenosis after DES.

The effects of acarbose treatment on intimal hyperplasia in a rat carotid endarterectomy model of diet-induced insulin resistance

BACKGROUND

Increased carotid restenosis due to revascularization therapy is associated with insulin resistance. We hypothesize that glucose control using acarbose may attenuate intimal hyperplasia in rat carotid endarterectomy model of diet-induced insulin resistance.

METHODS

Rats were fed low-fat complex carbohydrate (control) or high-fat sucrose (insulin resistance) for 4 months. Three days preoperatively, some high-fat-sucrose rats were on acarbose, remainder of the rats received placebo. Rat carotids were assessed with duplex pre-and postoperatively. Acarbose and placebo continued for 2 weeks. Glucose, insulin, blood flow velocities and intimal hyperplasia were determined.

RESULTS

High-fat sucrose plus acarbose attenuated intimal hyperplasia. Post-drug high-fat sucrose glucose decreased. Blood flow velocities postoperatively elevated above baseline. High-fat sucrose increased blood flow velocities postoperatively, which was attenuated with acarbose.

CONCLUSION

Glucose control by acarbose in rat carotid endarterectomy model of diet-induced insulin resistance resulted in attenuation of intimal hyperplasia.

Antithrombotic therapy in patients with coronary artery disease and with type 2 diabetes mellitus

Diabetes mellitus (DM) is a life-threatening disease. Patients with DM have a 2- to 4-fold higher risk of developing cardiovascular disease compared to their non-diabetic counterparts. Several drugs are available for the treatment of stable coronary artery disease (CAD) and acute coronary syndrome (ACS). Among oral antiplatelet agents (acetylsalicylic acid, ticlopidine, clopidogrel, and prasugrel), prasugrel has shown the highest efficacy in patients with DM and ACS. The use of glycoprotein IIb-IIIa receptor inhibitors in diabetic subjects with ACS undergoing percutaneous coronary intervention (PCI) reduces adverse clinical events in a greater extent than in non-diabetics. Several direct and indirect antithrombins are recommended for the treatment of ACS such as unfractionated heparin (UFH), enoxaparin, fondaparinux, and bivalirudin. Enoxaparin and bivalirudin have been shown to be superior to UFH among patients with ST-elevation MI (STEMI) and non-ST elevation MI (NSTEMI) also in diabetic subgroup analyses.

Enhanced proliferation and migration of vascular smooth muscle cells in response to vascular injury under hyperglycemic conditions is controlled by beta3 integrin signaling

Atheroma formation and restenosis following percutaneous vascular intervention involve the growth and migration of vascular smooth muscle cells (SMCs) into neointimal lesions, in part due to changes in the extracellular matrix. While some clinical studies have suggested that, in comparison to non-diabetics, beta3 integrin inhibition in diabetic patients confers protection from restenosis, little is known regarding the role of beta3 integrin inhibition on SMC responses in this context. To understand the molecular mechanisms underlying integrin-mediated regulation of SMC function in diabetes, we examined SMC responses in diabetic mice deficient in integrin beta3 and observed that the integrin was required for enhanced proliferation, migration and extracellular regulated kinase (ERK) activation. Hyperglycemia-enhanced membrane recruitment and catalytic activity of PKCbeta in an integrin beta3-dependent manner. Hyperglycemia also promoted SMC filopodia formation and cell migration, both of which required alphaVbeta3, PKCbeta, and ERK activity. Furthermore, the integrin-kinase association was regulated by the alphaVbeta3 integrin ligand thrombospondin and the integrin modulator Rap1 under conditions of hyperglycemia. These results suggest that there are differences in SMC responses to vascular injury depending on the presence or absence of hyperglycemia and that SMC response under hyperglycemic conditions is largely mediated through beta3 integrin signaling.

Comparison of medium-term outcomes obtained with drug-eluting stents and coronary artery bypass grafts in an unselected population of diabetic patients with multivessel coronary disease. Propensity score analysis

INTRODUCTION AND OBJECTIVES

Since the introduction of drug-eluting stents, the optimum revascularization strategy in diabetic patients with multivessel coronary disease has remained controversial.

METHODS

This study used multivariate logistic regression analysis and propensity score matching to compare results in 270 consecutive diabetic patients (2000-2004) with multivessel disease (> or =2 vessels with a >70% de novo stenosis involving the proximal left anterior descending coronary artery) who underwent either coronary artery bypass grafting (CABG; n=142) or implantation of a drug-eluting stent (DES; i.e. rapamycin or paclitaxel; n=128). The following clinical outcomes (i.e. major adverse cardiac or cerebrovascular events [MACCEs]) were assessed: death, nonfatal myocardial infarction (MI), stroke and repeat revascularization at 2 years.

RESULTS

Patients who received DESs were older (67.5+/-7 years vs. 65.3+/-8 years; P=.05) and more often had a previous MI (49.2% vs. 28.2%; P< .01), but no more often had a depressed left ventricular ejection fraction < or =45% (32.4% vs. 28.1%). Coronary anatomy was more complex in surgical patients (SYNTAX score, 25.9+/-7 vs. 18.5+/-6; P< .001) and the quality of revascularization was better (i.e. anatomically complete revascularization: 52.8% vs. 28.1%; P< .01). The incidence of MACCEs was 18.7% in the CABG group and 21.8% in the DES group (adjusted odds ratio [OR] = 0.93; 95% confidence interval [CI], 0.47-1.86). The composite endpoint of death, MI or stroke occurred in 15.8% undergoing CABG and 12.9% receiving a DES (adjusted OR = 1.19; 95% CI, 0.72-1.88). There was less need for revascularization in CABG patients (4.3% vs. 12.1%; adjusted OR = 0.42; 95% CI, 0.16-1.14; P=.09).

CONCLUSIONS

In an unselected population of diabetic patients with multivessel coronary disease, the principle advantage of CABG was the reduced need for revascularization. There was no difference in the rate of death, MI or stroke.

[Adjuvant drug treatment in diabetic patients undergoing percutaneous coronary intervention]

The authors describe the adjuvant drug treatment during and after percutaneous coronary intervention in order to obtain the reduction of major cardiovascular events, focusing in diabetic patients. In the clinical follow-up of diabetic patients after PCI, special attention to the control measures of cardiovascular risk factors should be observed. Among those measures, a normal glycemic level is fundamental, which can be achieved with usual clinical care. Antiplatelet therapy is a controversy issue until know. Although combined antiplatelet therapy with aspirin and a thienopyridynic is well supported by a number of clinical trials, adding GPIIb/IIIa agents as adjuvants in diabetic patients should not be irrestrictive as suggested by some authors; they should be restricted to patients with a significative thrombotic burden.

Clinical impact of drug-eluting stents in an unselected population of diabetic patients

BACKGROUND

Drug-eluting stents (DES) have been shown in randomized trials to reduce clinical events in diabetic patients. Our aim was to determine whether these clinical results are applicable in an unselected population of patients with non-insulin-dependent diabetes mellitus (NIDDM) and insulin-dependent diabetes mellitus (IDDM).

METHODS

We studied 440 consecutive patients (271 NIDDM and 169 IDDM) who underwent percutaneous coronary intervention, divided into 2 cohorts: Group A (1998-2000): 220 patients with bare metal stents, and Group B (2002-2004): 220 patients with drug-eluting stents. We analyzed major coronary adverse events (death, nonfatal acute myocardial infarction, and target lesion revascularization) over a mean follow-up of 18+/-15 months.

RESULTS

Group B had more patients who were insulin-dependent (44.5 versus 32.3% p<0.001) or had hypertension (64.5 versus 54.1%; p=0.02), a lower left ventricular ejection fraction (53.89 versus 56.8%; p=0.04), more complex lesions (B2/C) (82.7 versus 62.3%; p<0.001), more treated lesions (1.40 versus 1.26; p<0.001), more stents implanted (1.69 versus 1.15; p<0.0001), and more patients treated with abciximab (76.8 versus 42.7%; p<0.0001). During the follow-up, Group B had fewer major adverse coronary events (11.7 versus 27.9%; p<0.001) and a reduction in target lesion revascularization (3.9 versus 17.2%; p<0.001), with no differences in death or myocardial infarction. Both groups experienced a significant reduction in events (NIDDM: 8.1 versus 26.7%; p<0.001 and IDDM: 16 versus 31.9%; p=0.016). Multivariate regression analysis showed the use of drug-eluting stents to be in direct relation with event-free survival (odds ratio [OR]: 3.37; 95% confidence interval [CI], 1.44-7.90; p=0.005).

CONCLUSION

Despite the worse angiographic characteristics, the use of DES reduced clinical events, particularly target lesion revascularization.

Platelet hyperactivity in type 2 diabetes: role of antiplatelet agents

Type 2 diabetes mellitus increases atherothrombotic risk. Platelets in individuals with diabetes show increased activity at baseline and in response to agonists, ultimately leading to increased aggregation. Increased expression of platelet surface adhesion molecules and receptors, enhanced production of thromboxane and thrombin and disturbances in platelet calcium homeostasis are well documented. As intra-arterial thrombi are initiated by platelets, strategies to limit acute thrombotic events have largely focused on antiplatelet agents. Aspirin remains the cornerstone of antiplatelet therapy but appears to have limited benefit in diabetes. Use of thienopyridines and platelet glycoprotein IIb/IIIa receptor inhibitors has been shown to benefit high-risk patient populations. This review summarises the different platelet abnormalities characterised in diabetes and the role of currently used antiplatelet agents.

Comparison of effectiveness and safety of sirolimus-eluting stents versus bare-metal stents in patients with diabetes mellitus (from the Italian Multicenter Randomized DESSERT Study)

Few studies directly compared drug-eluting stents and bare-metal stents (BMSs) in diabetic patients. DESSERT was an Italian multicenter randomized trial to show the efficacy of sirolimus-eluting stents (SESs) compared with BMSs in de novo lesions of diabetic patients treated with insulin and/or oral antidiabetics for > or =3 months on top of glycoprotein IIb/IIIa inhibitors. The primary end point was in-stent late lumen loss, assessed using centralized quantitative coronary angiography at 8-month follow-up. Centrally adjudicated composite major adverse cardiac events (MACEs) and target-vessel failure (TVF; death, treated vessel-related acute myocardial infarction, and target-vessel revascularization) at 30 days and 9 and 12 months were secondary end points. Seventy-five patients were randomly assigned to an SES (109 lesions), and 75 (109 lesions), to a BMS. The 2 groups were well balanced for clinical, anatomic, and procedural characteristics. In-stent late lumen loss decreased from 0.96 +/- 0.61 mm for BMSs to 0.14 +/- 0.33 for SESs (p <0.001), and in-segment binary restenosis was 38.8% versus 3.6%, respectively (p <0.001). Twelve-month clinical events were significantly lower in the sirolimus group: MACEs 22.1% versus 40% (p = 0.023), target-lesion revascularization 5.9% versus 30% (p <0.001), and TVF 14.7% versus 34.3% (p = 0.008). At multivariate analysis, stent type was confirmed as an independent predictor of in-segment late loss (p <0.001), binary restenosis (p <0.001), 12-month TVF (p = 0.010), and 12-month MACEs (p = 0.037). In conclusion, the randomized DESSERT showed SESs to be safe and effective in decreasing both angiographic parameters of restenosis and incidence of MACEs compared with BMSs in diabetic patients with de novo 1- or 2-vessel coronary stenoses.

Effect of abciximab on clinical and angiographic restenosis in patients with non-ST-segment elevation acute coronary syndromes

The ISAR-REACT 2 trial was designed to assess the effect of abciximab in patients with acute coronary syndromes undergoing percutaneous coronary intervention after a 600-mg loading dose of clopidogrel. The aim of the present study was to investigate the impact of abciximab on clinical and angiographic restenosis after coronary stenting in patients with acute coronary syndromes. The angiographic substudy included 1,544 patients from the ISAR-REACT 2 trial randomly assigned to abciximab (771 patients) or placebo (773 patients). All patients were scheduled for routine angiographic follow-up at 6 to 8 months after intervention. The primary end point was incidence of angiographic in-segment binary restenosis. The secondary end point was 1-year incidence of target-lesion revascularization. Binary restenosis was observed in 21.9% of patients in the abciximab group and 24.5% of patients in the placebo group (p=0.29). Percentages of in-stent (29+/-22% vs 33+/-24%; p=0.02) and in-segment (35+/-20% vs 38+/-21%; p=0.04) diameter stenoses were significantly lower in the abciximab group than the placebo group. There was a strong trend toward lower 1-year incidence of target-lesion revascularization in patients treated with abciximab than in patients treated with placebo (13.6% vs 16.8%; p=0.08). In conclusion, in patients with non-ST-segment elevation acute coronary syndromes undergoing early percutaneous coronary intervention with stenting after a 600-mg loading dose of clopidogrel, abciximab therapy may have a slight positive impact on the prevention of restenosis.

Comparison of coronary flow reserve and fractional flow reserve in patients with versus without diabetes mellitus and having elective percutaneous coronary intervention and abciximab therapy (from the PREDICT Trial)

Patients with diabetes mellitus (DM) have poor long-term outcome after percutaneous coronary intervention (PCI) partly because of microvascular disease and distal embolization. Microvascular obstruction can be assessed by measuring coronary flow reserve (CFR). The Prediction of CK-MB RElease During Successful Stenting Correlating with Indicators of Microvascular ObstruCTion (PREDICT) trial compared the CFR in patients with versus without DM during PCI. Patients undergoing elective PCI were prospectively enrolled according to diabetic (n = 36) and nondiabetic (n = 36) status. All patients received drug-eluting stent with abciximab and were followed for 30-day major adverse cardiac events. CFR and FFR (fractional flow reserve) before and after stenting were measured before and after intracoronary adenosine bolus. Procedural success, MB enzyme of creatine-kinase (CK-MB), troponin I, and high-sensitive C-reactive protein elevation, vascular complications, and major adverse cardiac events were not different. FFR before stenting was 0.77 +/- 0.03 in patients with DM versus 0.76 +/- 0.02 in patients without DM (p = 0.69). FFR after stenting was 0.97 +/- 0.03 and 0.99 +/- 0.01 (p = 0.26), respectively. CFR before stenting was 1.36 +/- 0.31 in patients with DM versus 1.49 +/- 0.25 in patients without DM (p = 0.064). However, CFR after stenting was significantly lower in patients with versus without DM (1.89 +/- 0.30 versus 2.44 +/- 0.67, p <0.001, respectively). CFR after stenting only moderately correlated with CK-MB and high-sensitive C-reactive protein after PCI but did not correlate with 30-day major adverse cardiac events. In conclusion, patients with DM have significantly lower CFR after stenting despite equivalent FFR and myonecrosis compared with patients without DM, indicating greater microvascular obstruction after PCI despite abciximab.

Glycoprotein IIb/IIIa inhibitors: questioning indications and treatment algorithms

Glycoprotein inhibitors (GPI) are viewed as beneficial adjunctive pharmacotherapy agents for percutaneous coronary interventions (PCIs). The major benefit of GPI is derived from the reduction of ischemic events (mostly non-Q-wave myocardial infarctions) during PCI. There is no single randomized clinical trial demonstrating that any of these agents significantly reduces mortality in any clinical subset of patients. Studies of sustained oral GPI resulted in excessive death and myocardial infarctions. Reduction of ischemic end points was counteracted by excessive bleeding, vascular complications, and thrombocytopenia. These complications bear considerable medical and economic impact. The Acute Catheterization and Early Intervention Triage Strategy trial demonstrated that GPI, when added to heparin, enoxaparine, or bivalirudin, do not reduce mortality or ischemic events but significantly increase bleeding complications. Major bleeding resulted in threefold mortality at 1 year. In view of available data, the use of GPI should be limited to moderate-risk to high-risk PCI patients with low bleeding propensity. Protocols of abbreviated GPI administration and careful bleeding surveillance, in conjunction with lower doses of unfractionated heparin or new and possibly safer antithrombins, can potentially improve patient safety.

Abciximab offers greater benefits to insulin-dependent diabetic patients undergoing coronary stent implantation

INTRODUCTION AND OBJECTIVES

Abciximab use does not exceed 25% in most of the studies on diabetic patients undergoing stent implantation. The aim of this study was to evaluate whether abciximab could be more beneficial in different subgroups such as insulin-dependent (ID) patients and whether its use could provide additional benefits to those afforded by drug-eluting stents in these patients.

PATIENTS AND METHODS

A total of 373 consecutive diabetics [223 non-insulin-dependent (NID) and 150 ID patients] who had undergone stent implantation were examined with a follow-up of 25.6+/-16.2 months. Abciximab was used in 21.7%.

RESULTS

The abciximab-treated group had a lower rate of revascularization (26.8% vs. 15.8%. P=.02). The results by subgroups were as follows: NID nonabciximab, 23.5%; NID abciximab, 19% (P=NS); ID nonabciximab, 32.7%; ID abciximab, 12.2% (P=.05). In multivariate analysis, the restenosis predictors were insulin dependency (OR, 2.7), abciximab use (OR, 0.18), stent diameter (OR, 0.18).

CONCLUSIONS

Abciximab use in diabetics with stent implantation has a favorable effect by reducing the need for new revascularization. This benefit is more evident in ID patients; the negative prognosis effect of being insulin-dependent is eliminated, and the percentage of events in this population over a long follow-up period is equal to those in NID patients.

Elevated Plasma Fibrinogen Level Predicts Suboptimal Response to Therapy With Both Single- and Double-Bolus Eptifibatide During Percutaneous Coronary Intervention

OBJECTIVES

This study sought to determine the factors associated with suboptimal platelet inhibition (PI) with single- and double-bolus eptifibatide during percutaneous coronary intervention (PCI).

BACKGROUND

Although PI > or = 95% measured 10 min after glycoprotein IIb/IIIa inhibitor therapy is associated with improved outcomes following PCI, this level of PI often is not achieved.

METHODS

We prospectively studied 150 patients undergoing PCI with single-bolus eptifibatide (180 microg/kg) (n = 100) and double-bolus eptifibatide (180 microg/kg administered 10 min apart) (n = 50) followed by standard infusion (2 microg/kg/min). Measuring platelet aggregation at baseline and at 10 min and 30 to 45 min after eptifibatide bolus, patients were classified as optimal responders (OPT) (> or =95% PI) or suboptimal responders (sub-OPT) (<95% PI) based on 10-min PI after final bolus.

RESULTS

Suboptimal PI was achieved in 61% of patients with single-bolus eptifibatide and in 36% with double-bolus eptifibatide. In the single-bolus group, sub-OPT had higher fibrinogen levels (324 +/- 85 mg/dl vs. 259 +/- 49 mg/dl, p = 0.0002), platelet counts (221 +/- 70 vs. 186 +/- 47, p = 0.008), and white blood cell counts (7.7 +/- 2.3 vs. 6.6 +/- 1.9, p = 0.02). In the double-bolus group, sub-OPT also had higher fibrinogen levels (324 +/- 68 mg/dl vs. 278 +/- 53 mg/dl, p = 0.01) and were more likely to be smokers (38.9% vs. 9.4%, p = 0.01). Multivariable analysis showed that fibrinogen level was the only independent predictor of suboptimal PI, with fibrinogen cutoffs at 375 and 325 mg/dl predicting suboptimal PI (single-bolus: 100% and 90.0%, respectively; double-bolus: 100% and 60%, respectively) with both doses.

CONCLUSIONS

During PCI, both single- and double-bolus eptifibatide provide suboptimal PI in a substantial proportion of patients. A fibrinogen level >375 mg/dl is a strong predictor of suboptimal PI.

GP IIb/IIIa Blockade During Peripheral Artery Interventions

The activation of the platelet GP IIb/IIIa receptor is the final and common pathway in platelet aggregation. By blocking this receptor, platelet aggregation can be inhibited independently of the stimulus prompted the targeting of this receptor. Several years ago, three drugs have been approved for coronary artery indications. Since that time, there is increasing evidence that GP IIb/IIIa receptor blockade might have also an important role in peripheral arterial intervention. This article summarizes the action and differences of GP Ilb/IIIa receptor inhibitors and its possible indication in peripheral arteries.

Marked improvements in outcomes of contemporary percutaneous coronary intervention in patients with diabetes mellitus

We sought to determine if advances in percutaneous coronary intervention (PCI) are associated with better outcomes among patients with diabetes mellitus (DM). Patients with DM enrolled in the National Heart, Lung, and Blood Institute (NHLBI) early PTCA Registry (1985-1986) were compared to those in the subsequent contemporary Dynamic Registry (1999-2002) for in-hospital and one-year cardiovascular outcomes. The study population included 945 adults with DM, 325 from the PTCA Registry and 620 from the Dynamic Registry. Multivariable Cox regression models were built to estimate the risk of clinical events. Dynamic Registry patients were older, had more noncardiac comorbidities, and a lower mean ejection fraction (50.5% vs 57.8%, P < or = 0.001) compared to the PTCA Registry patients. The incidence of in-hospital mortality (1.9% vs 4.3%, P < or = 0.05), myocardial infarction (MI) (1.0% vs 7.4%, P <or = 0.001), and coronary artery bypass grafting (CABG) (0.8% vs 6.2%, P < or = 0.001) were all significantly lower and independent of the use of stents. One-year adverse events including MI (4.9% vs 11.0%, P < or = 0.001), CABG (6.4% vs 15.0%, P < or = 0.001), and need for repeat revascularization (18.7% vs 33.3%, P < or = 0.001) were all lower in the Dynamic Registry. The relative risk of death at 1 year was significantly less for patients in the Dynamic Registry (RR 0.56, 0.34; 0.92, P = 0.02). Although Dynamic Registry patients with diabetes had more advanced coronary disease, in-hospital and late adverse events were lower. A combination of the use of stents and an increase in adjunctive medical therapy are likely responsible for the observed improvements in outcomes in contemporary PCI.

Diabetes mellitus and coronary revascularization procedures

Revascularization strategy for coronary artery disease in diabetic patients remains a field of controversy. Percutaneous coronary intervention has a less favourable outcome in these patients, though drug eluting stents have significantly improved the outcome. Although in most series, the outcome with coronary artery bypass grafting is worse in diabetic populations, surgery seems to be superior to angioplasty, particularly in diabetics with multivessel disease. Results from randomized trials such as the ongoing FREEDOM, CARDia and SYNTAX may define the role of each procedure in the treatment of diabetic patients with coronary artery disease.

Coronary intervention in the diabetic patient: improved outcome following stent implantation compared with balloon angioplasty

BACKGROUND

Diabetic patients undergoing coronary interventional procedures are at increased risk of restenosis and adverse clinical events. The relative impact of stents compared with balloon angioplasty on the outcome of percutaneous intervention in diabetics remains controversial.

HYPOTHESIS

The goal of this study was to determine whether stent placement was superior to balloon angioplasty in reducing restenosis of diabetic patients undergoing coronary intervention.

METHODS

The STRESS Trial was a prospective randomized comparison of stent placement and balloon angioplasty in the treatment of new native coronary lesions. Of 594 randomized patients. 92 (16%) were diabetic. In this substudy analysis of the STRESS Trial, the outcomes after stenting and balloon angioplasty in diabetic patients were compared. The primary endpoint was restenosis as determined by angiography at 6 months. Clinical outcomes at 1 year were assessed.

RESULTS

Procedural success was achieved in 82% of diabetic patients assigned to angioplasty and in 100% assigned to stenting (p < 0.01). Compared with angioplasty, stenting resulted in a larger postprocedural lumen diameter (2.34 +/- 0.44 vs. 1.87 +/- 0.52 mm, p < 0.001) and greater acute luminal gain (1.61 +/- 0.47 vs. 1.06 +/- 0.46 mm, p < 0.001). At 6 months, stenting conferred a larger lumen (1.69 +/- 0.57 vs. 1.38 +/- 0.60 mm, p = 0.03) and greater net luminal gain (0.97 +/- 0.55 vs. 0.52 +/- 0.52 mm, p < 0.001). Restenosis occurred in 60% of the angioplasty group and in 24% of the stent group (p < 0.01). This was accompanied by a lower need for repeat target vessel revascularization after stenting (31 vs. 13%, p < 0.03).

CONCLUSIONS

Compared with balloon angioplasty, stent placement in diabetic patients with focal de novo lesions resulted in superior procedural results, reduced restenosis, and improved clinical outcome with fewer repeat revascularization procedures.

Medical treatment of patients with heart failure or left ventricular dysfunction undergoing percutaneous coronary intervention

Management of ischemic patients with pre-existing or new-onset left ventricular (LV) dysfunction poses a special challenge in terms of the timing of percutaneous coronary intervention (PCI) and appropriate adjunctive medications to optimize outcome while minimizing risk. In a systematic fashion, this review attempts to provide a management scheme for patients with heart failure or LV dysfunction that present with stable angina, ST-segment elevation myocardial infarction, or unstable angina/non-ST-segment elevation myocardial infarction. By addressing therapeutic approaches to acute or decompensated heart failure and timing of coronary angiography based on severity of ischemia, we provide evidence-based recommendations for medications to initiate before, during, and following PCI.

Percutaneous coronary revascularization in diabetics: from balloon angioplasty to drug-eluting stents

Diabetic patients may have aggressive coronary disease with an excessive rate of restenosis and accelerated atherosclerotic progression. This article reviews the different modalities of percutaneous treatment and their results in the diabetic population, from the early days of balloon angioplasty to the current implementation of drug-eluting stents. As restenosis may be virtually eradicated in the near future, plaque progression remains the cornerstone for interventional cardiologists and the medical community. In this regard, attempts to modify life habits, and a more accurate control of the components of the metabolic syndrome should be the main therapeutic objective.

Late outcomes after intervention of vein grafts in diabetics with abciximab use

OBJECTIVES

We sought to evaluate late clinical outcomes following elective percutaneous coronary interventions for saphenous vein graft with planned abciximab use in diabetics.

BACKGROUND

Diabetes adversely affects long-term outcomes after percutaneous coronary intervention including percutaneous coronary intervention of saphenous vein grafts. Glycoprotein IIb/IIIa inhibitors reduce adverse outcomes of native vessel percutaneous coronary intervention in diabetics; however, their effects in diabetic patients undergoing percutaneous coronary interventions of saphenous vein grafts is not known.

METHODS

We evaluated 509 elective percutaneous coronary interventions of saphenous vein grafts. Glycoprotein IIb/IIIa inhibitors were used in 99% of the percutaneous coronary interventions. Distal protection devices were not used. Clinical follow-up (mean 30+/-20 months) was available in 369/397 (93%).

RESULTS

Overall, procedural success rate was 97% and was similar for diabetics and non-diabetics. Procedural major adverse cardiac events occurred in 4.8% diabetics, and 4.1% non-diabetics (p = NS). Late outcomes were similar for diabetics and non-diabetics with major adverse cardiac event rates of 57.6%, and 54.9%, respectively, p=NS. Multivariate logistic regression identified graft age and the presence of thrombus as predictors of increased late major adverse cardiac events.

CONCLUSIONS

Following routine use of abciximab, late outcomes after percutaneous coronary interventions of saphenous vein grafts were similar for diabetics and non-diabetics suggesting that the historically observed adverse effect of diabetes on late outcomes after percutaneous coronary interventions of saphenous vein grafts may be attenuated by glycoprotein IIb/IIIa use. Selective use of glycoprotein IIb/IIIa inhibitor should be considered for diabetics undergoing percutaneous coronary interventions of saphenous vein grafts.

Abciximab and angiographic restenosis after coronary stent placement. Analysis of the angiographic substudy of ISAR-REACT--a double-blind, placebo-controlled, randomized trial evaluating abciximab in patients undergoing elective percutaneous coronary interventions after pretreatment with a high loading dose of clopidogrel

BACKGROUND

ISAR-REACT was a trial designed to evaluate whether the glycoprotein IIb/IIIa inhibitor abciximab is beneficial in patients undergoing elective percutaneous coronary intervention (PCI) with stent placement after pretreatment with a 600 mg loading dose of clopidogrel. Objective for the angiographic substudy was to determine the impact of abciximab on angiographic restenosis after coronary stent placement. Previous analyses have suggested a reduction in the incidence of restenosis after the administration of abciximab.

METHODS

The angiographic substudy comprises 1885 of 2159 patients enrolled in ISAR-REACT: 994 patients were randomly assigned to abciximab and 941 patients to placebo. All patients were scheduled for a routine angiographic follow-up after 6 months (performed in 80% of eligible patients). End points for the angiographic substudy were the rates of angiographic restenosis (> or = 50% diameter stenosis) and target lesion revascularization.

RESULTS

The incidence of angiographic restenosis was 27% in the abciximab group and 29% in the placebo group (relative risk 0.92, 95% CI 0.79-1.06, P = .27). Late angiographic lumen loss was 0.95 +/- 0.68 and 0.99 +/- 0.70 mm, respectively (P = .25). Similar results were obtained in a subgroup analysis focusing on high-risk subsets. The rate of target lesion revascularization procedures was 22% in the abciximab group and 23% in the placebo group (relative risk 0.94, 95% CI 0.79-1.12, P = .52).

CONCLUSIONS

In low- to intermediate-risk patients who undergo elective PCI after pretreatment with a high loading dose of clopidogrel >2 hours before PCI, the additional administration of the glycoprotein IIb/IIIa inhibitor abciximab is not associated with a significant reduction in angiographic restenosis.