Influence of timing of clopidogrel treatment on the efficacy and safety of bivalirudin in patients with non-ST-segment elevation acute coronary syndromes undergoing percutaneous coronary intervention: an analysis of the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial

OBJECTIVES

This study sought to determine if the efficacy of bivalirudin alone versus heparin plus a glycoprotein (GP) IIb/IIIa inhibitor is dependent upon the duration of clopidogrel pre-treatment in patients undergoing percutaneous coronary intervention (PCI) in the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial.

BACKGROUND

The administration of a clopidogrel loading dose several hours before PCI reduces the risk of periprocedural thrombotic events.

METHODS

Patients with an acute coronary syndrome were randomized to heparin plus a GP IIb/IIIa inhibitor (control), bivalirudin plus a GP IIb/IIIa inhibitor, or bivalirudin alone. Dose and timing of clopidogrel were left to the investigator's discretion.

RESULTS

Of 13,819 patients randomized, 7,789 underwent PCI. When clopidogrel was initiated at any time before angiography or within 30 min after PCI, randomization to bivalirudin alone (n = 2,284) or control (n = 2,189) was associated with similar ischemic outcomes (8.2% vs. 8.3%, risk ratio: 0.98, 95% confidence interval: 0.81 to 1.20). Those patients who received clopidogrel >30 min after PCI or not at all experienced an increase in ischemic events when randomized to bivalirudin alone (n = 290) versus control (n = 317) (14.1% vs. 8.5%, risk ratio: 1.66, 95% confidence interval: 1.05 to 2.63). Major bleeding was significantly less frequent in patients treated with bivalirudin alone.

CONCLUSIONS

This post-hoc analysis suggests that in acute coronary syndrome patients, as long as clopidogrel is administered before or within 30 min of PCI treatment with bivalirudin alone is similarly effective to heparin plus a GP IIb/IIIa inhibitor in suppressing 30-day ischemic events with significantly less bleeding. If it is anticipated that clopidogrel will be given late or not at all after PCI, bivalirudin alone may be associated with worse ischemic outcomes. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes; NCT00093158).

Impact of drug-eluting versus bare-metal stents on mortality in patients with anemia

OBJECTIVES

Our aim was to assess the incidence of all-cause mortality in patients with anemia undergoing percutaneous coronary intervention (PCI) receiving drug-eluting stents (DES) or bare-metal stents (BMS).

BACKGROUND

Anemia has been associated with poor clinical outcomes in patients undergoing PCI. However, it is unknown whether stent selection (DES or BMS) has a differential outcome in this high-risk group.

METHODS

Anemia was defined as a hematocrit below 36% for female subjects and below 40% for male subjects as defined by the World Health Organization. All patients undergoing PCI with DES or BMS alone from March 2003 to June 2007 were included. The primary end point was all-cause mortality. Anemia was further characterized using mean corpuscular volume as microcytic, normocytic, or macrocytic.

RESULTS

A total 11,181 patients underwent PCI over a 4.5-year interval; of these, 2,172 met our inclusion criteria. There were a total of 429 deaths. The majority of patients had normocytic anemia (n = 1,931). Of the 3 anemia subtypes, macrocytic anemia (DES 26%, BMS 44%) had the highest mortality followed by normocytic (DES 17%, BMS 25%) and microcytic (DES 13%, BMS 18%) anemia, respectively. All-cause mortality was significantly lower with DES in unadjusted and multivariable adjusted Cox proportional models (adjusted hazard ratio: 0.66, 95% confidence interval: 0.54 to 0.82; p < 0.001).

CONCLUSIONS

In an adjusted analysis, the use of DES as compared with the use of BMS was associated with decreased mortality in patients with anemia. Additionally, among anemia subtypes, macrocytic anemia had the highest mortality.

Early Stent Thrombosis in Patients With Acute Coronary Syndromes Treated With Drug-Eluting and Bare Metal Stents

Background— The clinical and angiographic predictors of early (<30 days) stent thrombosis (ST) have not been reported in high-risk patients with acute coronary syndromes.

Methods and Results— Qualitative and quantitative coronary angiographic analyses were performed in 3405 patients with moderate- and high-risk acute coronary syndromes in whom stents were implanted in the prospective randomized Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) trial, including 3043 patients (89.4%) in whom drug-eluting stents were implanted. Within 30 days, definite or probable ST occurred in 48 patients (1.4%). ST rates were not significantly different in patients treated with bare metal stents compared with drug-eluting stents (1.4% versus 1.4%; P =1.00) or with heparin plus glycoprotein IIb/IIIa inhibitors (1.1%) compared with bivalirudin with or without IIb/IIIa inhibitors (1.6% and 1.5%, respectively; P =0.26 and P =0.37, respectively). Compared with patients without ST, patients with ST more frequently had insulin-requiring diabetes mellitus and baseline renal insufficiency, a greater overall burden of coronary atherosclerosis, and suboptimal final angiographic results. ST also was more common in patients without preprocedural thienopyridine administration and with inconsistent antiplatelet drug use within 30 days. By multivariable analysis, the strongest independent predictors of definite ST were a smaller final stent minimal lumen diameter, a lack of preprocedural thienopyridine administration, the extent of coronary artery disease, and higher baseline hemoglobin level.

Conclusions— Occurring in nearly 1 in 70 patients, early ST is relatively common in acute coronary syndromes, occurs with similar frequency after anticoagulation with either heparin plus glycoprotein IIb/IIIa inhibitors or bivalirudin with or without IIb/IIIa inhibitors, and is predicted by diffuse atherosclerosis, suboptimal angiographic results, and inadequate pharmacotherapy.

Economic evaluation of bivalirudin with or without glycoprotein IIb/IIIa inhibition versus heparin with routine glycoprotein IIb/IIIa inhibition for early invasive management of acute coronary syndromes

OBJECTIVES

The aim of this study was to determine the economic impact of several anticoagulation strategies for moderate- and high-risk non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients managed invasively.

BACKGROUND

The ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial demonstrated that bivalirudin monotherapy yields similar rates of ischemic complications and less bleeding than regimens incorporating glycoprotein IIb/IIIa receptor inhibitors (GPI) for moderate- and high-risk NSTE-ACS.

METHODS

In ACUITY, 7,851 U.S. patients were randomized to: 1) heparin (unfractionated or enoxaparin) + GPI; 2) bivalirudin + GPI; or 3) bivalirudin monotherapy. Patients assigned to GPI were also randomized to upstream GPI before catheterization or selective GPI only with percutaneous coronary intervention. Resource use data were collected prospectively through 30-day follow-up. Costs were estimated with standard methods including resource-based accounting, hospital billing data, and the Medicare fee schedule.

RESULTS

At 30 days, ischemic events were similar for all groups. Major bleeding was reduced with bivalirudin monotherapy compared with heparin + GPI or bivalirudin + GPI (p < 0.001). Length of stay was lowest with bivalirudin monotherapy or bivalirudin + catheterization laboratory GPI (p = 0.02). Despite higher drug costs, aggregate hospital stay costs were lowest with bivalirudin monotherapy (mean difference range: $184 to $1,081, p < 0.001 for overall comparison) and at 30 days (mean difference range: $123 to $938, p = 0.005). Regression modeling demonstrated that hospital savings were primarily due to less major and minor bleeding with bivalirudin ($8,658/event and $2,282/event, respectively).

CONCLUSIONS

Among U.S. patients in the ACUITY trial, bivalirudin monotherapy compared with heparin + GPI resulted in similar protection from ischemic events, reduced bleeding, and shorter length of stay. Despite higher drug costs, aggregate hospital and 30-day costs were lowest with bivalirudin monotherapy. Thus bivalirudin monotherapy seems to be an economically attractive alternative to heparin + GPI for patients with moderate- and high-risk NSTE-ACS. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes [ACS]; NCT00093158).

Relation between previous lipid-lowering therapy and infarct size (creatine kinase-MB level) in patients presenting with acute myocardial infarction

Animal experimental data have shown that lipid-lowering agents reduce myocardial infarct size. This association has not been well studied in humans. We compared infarct size in 10,548 patients in the GUSTO IIb and PURSUIT trials who were (n = 1,028) or were not (n = 9,520) on lipid-lowering therapy before an enrolling myocardial infarction (MI). Patients using lipid-lowering agents before their index MI had smaller infarcts than those who were not using these agents (median peak creatine kinase [CK]-MB 4.2 vs 5.2 times the upper limit of normal [ULN]; p <0.0001). Similarly, in an unadjusted model, patients on previous lipid-lowering therapy were less likely to have a peak CK-MB >3 times the ULN (620 of 1,028 [60.3%] vs 6,486 of 9,520 patients [68.1%]; p <0.001; relative risk 0.88, 95% confidence interval 0.84 to 0.93, p <0.0001). In a covariate- and propensity-adjusted multivariable model, the association between pretreatment with lipid-lowering agents and smaller infarct size persisted (relative risk for CK-MB >3 times the ULN 0.94, 95% confidence interval 0.88 to 0.99, p = 0.04). In conclusion, patients on lipid-lowering agents before an MI had significantly smaller infarcts. These findings suggest that lipid-lowering therapy may exert additional salutary effects in the setting of acute coronary syndromes.

Treatment and prevention of heparin-induced thrombocytopenia: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition)

This chapter about the recognition, treatment, and prevention of heparin-induced thrombocytopenia (HIT) is part of the Antithrombotic and Thrombolytic Therapy: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patient values may lead to different choices. Among the key recommendations in this chapter are the following: For patients receiving heparin in whom the clinician considers the risk of HIT to be > 1.0%, we recommend platelet count monitoring over no platelet count monitoring (Grade 1C). For patients who are receiving heparin or have received heparin within the previous 2 weeks, we recommend investigating for a diagnosis of HIT if the platelet count falls by >/= 50%, and/or a thrombotic event occurs, between days 5 and 14 (inclusive) following initiation of heparin, even if the patient is no longer receiving heparin therapy when thrombosis or thrombocytopenia has occurred (Grade 1C). For patients with strongly suspected (or confirmed) HIT, whether or not complicated by thrombosis, we recommend use of an alternative, nonheparin anticoagulant (danaparoid [Grade 1B], lepirudin [Grade 1C], argatroban [Grade 1C], fondaparinux [Grade 2C], or bivalirudin [Grade 2C]) over the further use of unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) therapy or initiation/continuation of vitamin K antagonists (VKAs) [Grade 1B]. The guidelines include specific recommendations for nonheparin anticoagulant dosing that differ from the package inserts. For patients with strongly suspected or confirmed HIT, we recommend against the use of vitamin K antagonist (VKA) [coumarin] therapy until after the platelet count has substantially recovered (usually, to at least 150 x 10(9)/L) over starting VKA therapy at a lower platelet count (Grade 1B); that VKA therapy be started only with low maintenance doses (maximum, 5 mg of warfarin or 6 mg of phenprocoumon) over higher initial doses (Grade 1B); and that the nonheparin anticoagulant (eg, lepirudin, argatroban, danaparoid) be continued until the platelet count has reached a stable plateau, the international normalized ratio (INR) has reached the intended target range, and after a minimum overlap of at least 5 days between nonheparin anticoagulation and VKA therapy rather than a shorter overlap (Grade 1B). For patients receiving VKAs at the time of diagnosis of HIT, we recommend use of vitamin K (10 mg po or 5 to 10 mg IV) [Grade 1C].

Safety and efficacy of switching from either unfractionated heparin or enoxaparin to bivalirudin in patients with non-ST-segment elevation acute coronary syndromes managed with an invasive strategy: results from the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial

OBJECTIVES

The aim of this study was to compare outcomes in patients receiving consistent unfractionated heparin (UFH)/enoxaparin (ENOX) therapy and in those switched at randomization to bivalirudin monotherapy.

BACKGROUND

Crossover between UFH and ENOX has been associated with increased adverse outcomes in patients with acute coronary syndromes. The ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial demonstrated superior net clinical outcomes with similar rates of ischemia and significantly less major bleeding with bivalirudin monotherapy compared with UFH/ENOX plus a glycoprotein (GP) IIb/IIIa inhibitor. It is unknown if these results would be preserved in patients switched from UFH/ENOX to bivalirudin monotherapy.

METHODS

We compared composite ischemia, major bleeding, and net clinical outcomes at 30 days in patients receiving consistent UFH/ENOX therapy and in those switched at randomization from pre-treatment with UFH/ENOX to bivalirudin monotherapy. We also compared outcomes in patients naive to antithrombin therapy who were randomized to UFH/ENOX or bivalirudin monotherapy.

RESULTS

Two thousand one hundred thirty-seven patients received consistent UFH/ENOX (UFH n = 1,294, ENOX n = 843), and 2,078 patients pre-treated with UFH/ENOX were switched to bivalirudin. Patients switching to bivalirudin had similar rates of ischemia (6.9% vs. 7.4%, p = 0.52), less major bleeding (2.8% vs. 5.8%, p < 0.01), and improved net clinical outcomes (9.2% vs. 11.9%, p < 0.01) than those on consistent UFH/ENOX plus a GP IIb/IIIa inhibitor. Patients naive to antithrombin therapy who were administered bivalirudin (n = 1,427) had similar rates of ischemia (6.2% vs. 5.5%, p = 0.47), less major bleeding (2.5% vs. 4.9%, p < 0.001), and similar net clinical outcomes (8.0% vs. 9.4%, p = 0.17) compared with naive patients administered UFH/ENOX plus a GP IIb/IIIa inhibitor (n = 1,462).

CONCLUSIONS

Switching from UFH/ENOX to bivalirudin monotherapy results in comparable ischemic outcomes and an approximately 50% reduction in major bleeding compared with consistent UFH/ENOX plus a GP IIb/IIIa inhibitor. Patients naive to antithrombin therapy administered bivalirudin monotherapy had a significant reduction in bleeding and similar rates of ischemia compared with naive patients initiated with UFH or ENOX plus a GP IIb/IIIa inhibitor.

Comparison of pioglitazone vs glimepiride on progression of coronary atherosclerosis in patients with type 2 diabetes: the PERISCOPE randomized controlled trial

CONTEXT

No antidiabetic regimen has demonstrated the ability to reduce progression of coronary atherosclerosis. Commonly used oral glucose-lowering agents include sulfonylureas, which are insulin secretagogues, and thiazolidinediones, which are insulin sensitizers.

OBJECTIVE

To compare the effects of an insulin sensitizer, pioglitazone, with an insulin secretagogue, glimepiride, on the progression of coronary atherosclerosis in patients with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

Double-blind, randomized, multicenter trial at 97 academic and community hospitals in North and South America (enrollment August 2003-March 2006) in 543 patients with coronary disease and type 2 diabetes.

INTERVENTIONS

A total of 543 patients underwent coronary intravascular ultrasonography and were randomized to receive glimepiride, 1 to 4 mg, or pioglitazone, 15 to 45 mg, for 18 months with titration to maximum dosage, if tolerated. Atherosclerosis progression was measured by repeat intravascular ultrasonography examination in 360 patients at study completion.

MAIN OUTCOME MEASURE

Change in percent atheroma volume (PAV) from baseline to study completion.

RESULTS

Least squares mean PAV increased 0.73% (95% CI, 0.33% to 1.12%) with glimepiride and decreased 0.16% (95% CI, -0.57% to 0.25%) with pioglitazone(P = .002). An alternative analysis imputing values for noncompleters based on baseline characteristics showed an increase in PAV of 0.64% (95% CI, 0.23% to 1.05%) for glimepiride and a decrease of 0.06% (-0.47% to 0.35%) for pioglitazone (between-group P = .02). Mean (SD) baseline HbA(1c) levels were 7.4% (1.0%) in both groups and declined during treatment an average 0.55% (95% CI, -0.68% to -0.42%) with pioglitazone and 0.36% (95% CI, -0.48% to -0.24%) with glimepiride (between-group P = .03). In the pioglitazone group, compared with glimepiride, high-density lipoprotein levels increased 5.7 mg/dL (95% CI, 4.4 to 7.0 mg/dL; 16.0%) vs 0.9 mg/dL (95% CI, -0.3 to 2.1 mg/dL; 4.1%), and median triglyceride levels decreased 16.3 mg/dL (95% CI, -27.7 to -11.0 mg/dL; 15.3%) vs an increase of 3.3 mg/dL (95% CI, -10.7 to 11.7 mg/dL; 0.6%) (P < .001 for both comparisons). Median fasting insulin levels decreased with pioglitazone and increased with glimepiride (P < .001). Hypoglycemia was more common in the glimepiride group and edema, fractures, and decreased hemoglobin levels occurred more frequently in the pioglitazone group.

CONCLUSION

In patients with type 2 diabetes and coronary artery disease, treatment with pioglitazone resulted in a significantly lower rate of progression of coronary atherosclerosis compared with glimepiride.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00225277.

Effect of rimonabant on progression of atherosclerosis in patients with abdominal obesity and coronary artery disease: the STRADIVARIUS randomized controlled trial

CONTEXT

Abdominal obesity is associated with metabolic abnormalities and increased risk of atherosclerotic cardiovascular disease. However, no obesity management strategy has demonstrated the ability to slow progression of coronary disease.

OBJECTIVE

To determine whether weight loss and metabolic effects of the selective cannabinoid type 1 receptor antagonist rimonabant reduces progression of coronary disease in patients with abdominal obesity and the metabolic syndrome.

DESIGN, SETTING, AND PATIENTS

Randomized, double-blinded, placebo-controlled, 2-group, parallel-group trial (enrollment December 2004-December 2005) comparing rimonabant with placebo in 839 patients at 112 centers in North America, Europe, and Australia.

INTERVENTIONS

Patients received dietary counseling, were randomized to receive rimonabant (20 mg daily) or matching placebo, and underwent coronary intravascular ultrasonography at baseline (n = 839) and study completion (n = 676).

MAIN OUTCOME MEASURES

The primary efficacy parameter was change in percent atheroma volume (PAV); the secondary efficacy parameter was change in normalized total atheroma volume (TAV).

RESULTS

In the rimonabant vs placebo groups, PAV (95% confidence interval [CI]) increased 0.25% (-0.04% to 0.54%) vs 0.51% (0.22% to 0.80%) (P = .22), respectively, and TAV decreased 2.2 mm3 (-4.09 to -0.24) vs an increase of 0.88 mm3 (-1.03 to 2.79) (P = .03). In the rimonabant vs placebo groups, imputing results based on baseline characteristics for patients not completing the trial, PAV increased 0.25% (-0.04% to 0.55%) vs 0.57% (0.29% to 0.84%) (P = .13), and TAV decreased 1.95 mm3 (-3.8 to -0.10) vs an increase of 1.19 mm3 (-0.73 to 3.12) (P = .02). Rimonabant-treated patients had a larger reduction in body weight (4.3 kg [-5.1 to -3.5] vs 0.5 kg [-1.3 to 0.3]) and greater decrease in waist circumference (4.5 cm [-5.4 to -3.7] vs 1.0 cm [-1.9 to -0.2]) (P < .001 for both comparisons). In the rimonabant vs placebo groups, high-density lipoprotein cholesterol levels increased 5.8 mg/dL (4.9 to 6.8) (22.4%) vs 1.8 mg/dL (0.9 to 2.7) (6.9%) (P < .001), and median triglyceride levels decreased 24.8 mg/dL (-35.4 to -17.3) (20.5%) vs 8.9 mg/dL (-14.2 to -1.8) (6.2%) (P < .001). Rimonabant-treated patients had greater decreases in high-sensitivity C-reactive protein (1.3 mg/dL [-1.7 to -1.2] [50.3%] vs 0.9 mg/dL [-1.4 to -0.5] [30.9%]) and less increase in glycated hemoglobin levels (0.11% [0.02% to 0.20%] vs 0.40% [0.31% to 0.49%]) (P < .001 for both comparisons). Psychiatric adverse effects were more common in the rimonabant group (43.4% vs 28.4%, P < .001).

CONCLUSIONS

After 18 months of treatment, the study failed to show an effect for rimonabant on disease progression for the primary end point (PAV) but showed a favorable effect on the secondary end point (TAV). Determining whether rimonabant is useful in management of coronary disease will require additional imaging and outcomes trials, which are currently under way.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00124332.

Pharmacologic inhibition of platelet function: correlation between in vitro tests of platelet function and clinical outcomes

Atherothrombosis continues to be a leading cause of death and disability despite advances in pharmacologic and procedural therapies. Antiplatelet agents have been extensively studied and validated to improve outcomes in multiple settings of cardiovascular disease. The emergence of the phenomenon of resistance to antiplatelet therapy resulted in the availability of platelet function tests to assess the effectiveness of these agents. Subsequent evaluations have shown considerable inter-individual variability in platelet inhibition in patients receiving antiplatelet agents. Several small studies showed that patients who were deemed 'resistant' to antiplatelet therapy by platelet function testing had adverse clinical outcomes. It is essential that ongoing investigations help delineate a standard definition of 'resistance' to antiplatelet therapy, which test of platelet function should be the gold standard, and what therapy, once identified, can help overcome resistance to the currently available antiplatelet agents. Data are needed to determine if outcomes can be improved by changes to existing antiplatelet therapy based on the results of platelet function tests. Alternatively, newer antiplatelet agents may prove effective in overcoming resistance; however, these agents also await validation in large-scale clinical trials.

Antithrombotic strategies in patients with acute coronary syndromes undergoing early invasive management: one-year results from the ACUITY trial

CONTEXT

At 30-day follow-up, patients with moderate- and high-risk acute coronary syndromes (ACS) undergoing early invasive treatment in the ACUITY trial with bivalirudin monotherapy vs heparin plus glycoprotein (GP) IIb/IIIa inhibitors had noninferior rates of adverse ischemic events with reduced rates of major bleeding. Deferred upstream use of GP IIb/IIIa inhibitors for selective administration to patients undergoing percutaneous coronary intervention (PCI) resulted in a significant reduction in major bleeding, although a small increase in composite ischemia could not be excluded.

OBJECTIVE

To determine 1-year ischemic outcomes for patients in the ACUITY trial.

DESIGN, SETTING, AND PATIENTS

A prospective, randomized, open-label trial with 1-year clinical follow-up at 450 academic and community-based institutions in 17 countries. A total of 13,819 patients with moderate- and high-risk ACS undergoing invasive treatment were enrolled between August 23, 2003, and December 5, 2005.

INTERVENTIONS

Patients were assigned to heparin plus GP IIb/IIIa inhibitors (n = 4603), bivalirudin plus GP IIb/IIIa inhibitors (n = 4604), or bivalirudin monotherapy (n = 4612). Of these patients, 4605 were assigned to routine upstream GP IIb/IIIa administration and 4602 were deferred to selective GP IIb/IIIa inhibitor administration.

MAIN OUTCOME MEASURE

Composite ischemia (death, myocardial infarction, or unplanned revascularization for ischemia) at 1 year.

RESULTS

Composite ischemia at 1 year occurred in 15.4% of patients assigned to heparin plus GP IIb/IIIa inhibitors and 16.0% assigned to bivalirudin plus GP IIb/IIIa inhibitors (compared with heparin plus GP IIb/IIIa inhibitors, HR, 1.05; 95% CI, 0.95-1.16; P = .35), and 16.2% assigned to bivalirudin monotherapy (HR, 1.06; 95% CI, 0.95-1.17; P = .29). Mortality at 1 year occurred in an estimated 3.9% of patients assigned to heparin plus GP IIb/IIIa inhibitors, 3.9% assigned to bivalirudin plus GP IIb/IIIa inhibitors (HR, 0.99; 95% CI, 0.80-1.22; P = .92), and 3.8% assigned to bivalirudin monotherapy (HR, 0.96; 95% CI, 0.77-1.18; P = .67). Composite ischemia occurred in 16.3% of patients assigned to deferred use compared with 15.2% of patients assigned to upstream administration (HR, 1.08; 95% CI, 0.97-1.20; P = .15).

CONCLUSIONS

At 1 year, no statistically significant difference in rates of composite ischemia or mortality among patients with moderate- and high-risk ACS undergoing invasive treatment with the 3 therapies was found. There was no statistically significant difference in the rates of composite ischemia between patients receiving routine upstream administration of GP IIb/IIIa inhibitors vs deferring their use for patients undergoing PCI.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00093158.

Impact of female sex on death and bleeding after fibrinolytic treatment of myocardial infarction in GUSTO V

BACKGROUND

Women with acute myocardial infarction are more likely than men to experience reinfarction, bleeding, or death. This difference has been hypothesized to be due to older age, treatment delay, and comorbidities in women. Use of diagnostic and therapeutic modalities may also differ. There is controversy regarding whether female sex is an independent risk factor for death and/or bleeding.

METHODS

The GUSTO (Global Use of Strategies to Open Occluded Arteries in Acute Coronary Syndromes) V Investigators studied standard-dose reteplase vs standard-dose abciximab plus half-dose reteplase in patients with myocardial infarction.

RESULTS

Women were older and more often had diabetes mellitus and hypertension. Angiography and percutaneous coronary intervention were less frequent in women. Death (9.8% vs 4.4% at 30 days; odds ratio [OR], 2.00; 95% confidence interval, 1.59-2.53; P < .001) and bleeding (6.4% vs 2.5%; OR, 1.31; 95% confidence interval, 1.18-1.45; P < .01) were more common in women. There was no association between treatment assignment and death in either sex; bleeding was more common in both sexes receiving combination therapy. Female sex was independently associated with mortality. After Killip class greater than 1 (OR, 4.7), female sex (OR, 2.0) was the strongest correlate of death. Female sex was independently associated with bleeding for both treatments.

CONCLUSIONS

Female sex is independently associated with death and bleeding complications among fibrinolytic-treated patients with myocardial infarction. There remains a sex differential in the use of angiography and, therefore, percutaneous coronary intervention after fibrinolysis. Further research will determine what mediates excess risk in women.

Pioglitazone and risk of cardiovascular events in patients with type 2 diabetes mellitus: a meta-analysis of randomized trials

CONTEXT

Pioglitazone is widely used for glycemic control in patients with type 2 diabetes mellitus, but evidence is mixed regarding the influence of medications of this class on cardiovascular outcomes.

OBJECTIVE

To systematically evaluate the effect of pioglitazone on ischemic cardiovascular events.

DATA SOURCES AND STUDY SELECTION

A database containing individual patient-level time-to-event data collected during pioglitazone clinical trials was transferred from the drug's manufacturer for independent analysis. Trials were included if they were randomized, double-blinded, and controlled with placebo or active comparator.

DATA EXTRACTION

The primary outcome was a composite of death, myocardial infarction, or stroke. Secondary outcome measures included the incidence of serious heart failure. A fixed-effects approach was used to combine the estimates across the duration strata and statistical heterogeneity across all the trials was tested with the I2 statistic.

DATA SYNTHESIS

A total of 19 trials enrolling 16 390 patients were analyzed. Study drug treatment duration ranged from 4 months to 3.5 years. Death, myocardial infarction, or stroke occurred in 375 of 8554 patients (4.4%) receiving pioglitazone and 450 of 7836 patients (5.7%) receiving control therapy (hazard ratio [HR], 0.82; 95% confidence interval [CI], 0.72-0.94; P = .005). Progressive separation of time-to-event curves became apparent after approximately 1 year of therapy. Individual components of the primary end point were all reduced by a similar magnitude with pioglitazone treatment, with HRs ranging from 0.80 to 0.92. Serious heart failure was reported in 200 (2.3%) of the pioglitazone-treated patients and 139 (1.8%) of the control patients (HR, 1.41; 95% CI, 1.14-1.76; P = .002). The magnitude and direction of the favorable effect of pioglitazone on ischemic events and unfavorable effect on heart failure was homogeneous across trials of different durations, for different comparators, and for patients with or without established vascular disease. There was no evidence of heterogeneity across the trials for either end point (I2 = 0%; P = .87 for the composite end point and I2 = 0%; P = .97 for heart failure).

CONCLUSIONS

Pioglitazone is associated with a significantly lower risk of death, myocardial infarction, or stroke among a diverse population of patients with diabetes. Serious heart failure is increased by pioglitazone, although without an associated increase in mortality.

Off-Pump Coronary Artery Bypass With Bivalirudin for Patients With Heparin-Induced Thrombocytopenia or Antiplatelet Factor Four/Heparin Antibodies

BACKGROUND

This study assessed the use of bivalirudin as an alternative anticoagulant in patients with heparin-induced thrombocytopenia-thrombotic syndrome (HIT/TS) or antiplatelet factor four-heparin (anti-PF4/H) antibodies undergoing off-pump coronary artery bypass (OPCAB).

METHODS

In a prospective, open-label, multicenter study, fifty-one patients with documented anti-PF4/H antibodies and (or) HIT/TS underwent OPCAB with bivalirudin anticoagulation (0.75 mg/kg i.v. bolus, 1.75 mg/kg/hour infusion). Procedural success (absence of death, Q-wave myocardial infarction, repeat revascularization, and stroke), bleeding, and transfusion at day seven/discharge, thirty days, and twelve weeks were assessed.

RESULTS

Thirty-five patients (67%) were included with positive anti-PF4/H antibodies and no thrombocytopenia or thrombosis, eleven patients (22%) had thrombocytopenia, and five patients had clinical HIT/TS (10%). Procedural success at seven days/discharge was achieved in forty-seven patients (92%), while procedural success at thirty days and twelve weeks was 88%. There were no deaths. Chest tube output over the first twenty-four hours was 936 +/- 525 mL and twenty-five patients received a red blood cell transfusion during their hospitalization. Two patients required reexploration for persistent postoperative hemorrhage.

CONCLUSIONS

Bivalirudin was an effective alternative anticoagulant for patients with HIT/TS or circulating anti-PF4/H antibodies undergoing OPCAB, with high rates of procedural success and an acceptable incidence of bleeding or transfusions.

The role of clopidogrel in the management of ischemic heart disease

PURPOSE OF REVIEW

Platelet inhibition remains a key component in the prevention and treatment of ischemic heart disease. This review documents recent advances in the use of clopidogrel for the management of myocardial ischemia.

RECENT FINDINGS

For the prevention of ischemic heart disease, the addition of clopidogrel is not superior to aspirin alone at reducing short or long-term major adverse cardiac events. In patients with ST-segment elevation myocardial infarction who receive thrombolytics, clopidogrel therapy confers broad benefits including survival when initiated at the time of presentation. Long-term administration of clopidogrel is necessary to prevent thrombotic complications following coronary stent placement. Overall, there are no major safety concerns across the spectrum of cardiac indications for clopidogrel.

SUMMARY

Clopidogrel has become a cornerstone of therapy in the treatment of acute ischemic coronary syndromes and as prevention of thrombosis after coronary stenting. It has demonstrated safety and efficacy in most aspects of ischemic heart disease. Questions remain about optimal duration of therapy following deployment of drug-eluting stents.

Development and validation of a prognostic risk score for major bleeding in patients undergoing percutaneous coronary intervention via the femoral approach

AIMS

Major bleeding after percutaneous coronary intervention (PCI) is an independent risk factor for early and late mortality. We developed and validated a risk score predictive of major bleeding after PCI using the femoral approach.

METHODS AND RESULTS

Baseline clinical and procedural variables from two contemporary, multicentre, randomized PCI trials were used for risk score development (the REPLACE-2 trial, n = 6002) and validation (the REPLACE-1 trial, n = 1056). On the basis of the odds ratio, independent risk factors were assigned a weighted integer, the sum of which comprised a total risk score. Seven variables were identified as independent correlates of major bleeding (age >55 years, female gender, estimated glomerular filtration rate <60 mL/min/1.73 m(2), pre-existing anaemia, administration of low-molecular-weight heparin within 48 h pre-PCI, use of glycoprotein IIb/IIIa inhibitors, and intraaortic balloon pump use). In the development set, the risk of major bleeding varied from 1.0% in patients without risk factors to 5.4% in high-risk patients. The discriminatory power of this risk model was confirmed in the validation data set (area under the receiver operating curve = 0.62).

CONCLUSION

A simple risk score of baseline clinical and procedural variables is useful to predict the incidence of major peri-procedural bleeding after contemporary PCI using the femoral approach.

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

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