Mina Madan

Glycoprotein IIb/IIIa Integrin Blockade

Glycoprotein IIb/IIIa Integrin Blockade Print ISSN: 0009-7322. Online ISSN: 1524-4539 Copyright

Rationale and design of the randomized, double-blind trial testing INtraveNous and Oral administration of elinogrel, a selective and reversible P2Y12-receptor inhibitor, versus clopidogrel to eVAluate Tolerability and Efficacy in nonurgent Percutaneous Coronary Interventions patients (INNOVATE-PCI)

Despite current dual-antiplatelet therapy with aspirin and clopidogrel, adverse clinical events continue to occur during and after percutaneous coronary intervention (PCI). The failure of clopidogrel to provide optimal protection may be related to delayed onset of action, interpatient variability in its effect, and an insufficient level of platelet inhibition. Furthermore, the irreversible binding of clopidogrel to the P2Y(12) receptor for the life span of the platelet is associated with increased bleeding risk especially during urgent or emergency surgery. Novel antiplatelet agents are required to improve management of patients undergoing PCI. Elinogrel is a potent, direct-acting (ie, non-prodrug), selective, competitive, and reversible P2Y(12) inhibitor available in both intravenous and oral formulations. The INNOVATE-PCI study is a phase 2 randomized, double-blind, clopidogrel-controlled trial to evaluate the safety, tolerability, and preliminary efficacy of this novel antiplatelet agent in patients undergoing nonurgent PCI.

A randomized, double-blind, active-controlled phase 2 trial to evaluate a novel selective and reversible intravenous and oral P2Y 12 inhibitor elinogrel versus clopidogrel in patients undergoing nonurgent percutaneous coronary intervention: The INNOVATE-PCI trial

Background— We evaluated the safety, efficacy, and tolerability of elinogrel, a competitive, reversible intravenous and oral P2Y12 inhibitor that does not require metabolic activation, in patients undergoing nonurgent percutaneous coronary intervention. Methods and Results— In a randomized, double-blind, dose-ranging phase 2b trial, 652 patients received either 300 or 600 mg of clopidogrel pre-percutaneous coronary intervention followed by 75 mg daily or 80 or 120 mg of IV elinogrel followed by 50, 100, or 150 mg oral elinogrel twice daily. Numerous exploratory safety and efficacy end points were assessed and, as such, had no prespecified primary end point, and the study was not powered to conclusively evaluate its objectives. Thrombolysis in myocardial infarction combined bleeding was increased with elinogrel (hazard ratio, 1.98; 95% confidence interval, 1.10 to 3.57), related largely to increased bleeding requiring medical attention (elinogrel 47/408 [11.5%] versus clopidogrel 13/208 [6.3%]) and occurring primarily at the percutaneous coronary intervention access site. Efficacy end points and postprocedure cardiac enzyme were similar, but there was a nonsignificant higher frequency of periprocedural myocardial infarctions in the elinogrel arms (OR, 1.59; 95% confidence interval, 0.79 to 3.48). There was an increased incidence of dyspnea (elinogrel 50/408 [12.3%] versus clopidogrel 8/208 [3.8%]) and transaminase elevation (alanine transferase/aspartate transferase >3× the upper limit of normal; elinogrel 18/408 [4.4%] versus clopidogrel 2/208 [1.0%]) in the elinogrel arms, but there were no cases of heart block, bradycardia, hypotension, or liver failure. Conclusions— In patients undergoing nonurgent percutaneous coronary intervention and in comparison with clopidogrel, intravenous and oral elinogrel therapy did not significantly increase thrombolysis in myocardial infarction major or minor bleeding, although bleeding requiring medical attention was more common. The significance of these findings will need to be more definitively determined in future Phase 3 studies. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00751231.

Is glycoprotein IIb/IIIa antagonism as effective in women as in men following percutaneous coronary intervention?. Lessons from the ESPRIT study.

OBJECTIVE The study was done to determine whether eptifibatide, a platelet glycoprotein (GP) IIb/IIIa antagonist, prevents ischemic complications following percutaneous coronary interventions (PCIs) in women as well as in men. BACKGROUND Eptifibatide reduces ischemic complications after nonurgent coronary stent interventions. METHODS We compared outcomes in women (n = 562) and men (n = 1,502) enrolled in the Enhanced Suppression of the Platelet GP IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial of double-bolus eptifibatide during PCI. RESULTS Women in the ESPRIT trial were older, and more frequently had hypertension, diabetes mellitus, or acute coronary syndromes, but were less likely to have prior PCI or coronary artery bypass graft surgery. The primary end point, a composite at 48 h of death, myocardial infarction (MI), urgent target vessel revascularization (TVR), and unplanned GP IIb/IIIa use, occurred in 10.5% of women and 7.9% of men (p = 0.082). The composite of death, MI, or TVR after one year occurred in 24.5% of women compared with 18% of men (p = 0.0008). At 48 h, eptifibatide reduced the composite of death, MI, and TVR from 14.5% to 6.0% in women versus 9.0% to 6.8% in men. At one year, these differences persisted: 28.9% versus 20.0% for women and 19.5% versus 16.6% for men. No statistical interaction existed between treatment and gender at either 48 h (p = 0.063) or one year (p = 0.2). Bleeding occurred more commonly in women (5.5% vs. 2.6%, p = 0.002), and was more common in eptifibatide-treated women. After adjustment for age, weight, and hypertension, no interaction between treatment and gender was present. CONCLUSION Eptifibatide is effective to prevent ischemic complications of PCI in women and may eliminate gender-related differences in PCI outcomes.

Efficacy of Abciximab readministration in coronary intervention

Abciximab, an Fab monoclonal antibody fragment that blocks the platelet glycoprotein IIb/IIIa receptor, is increasingly used as an adjunct to coronary intervention. Little is known, however, about the efficacy and safety of readministration of abciximab. This study examined and characterized outcomes of patients receiving abciximab for a second time. From April 1995 to June 1997, 164 consecutive patients were readministered abciximab at our 3 institutions. We retrospectively examined and analyzed in-hospital outcomes in this cohort. The median time to readministration was 95 days. The angiographic success rate of percutaneous intervention was 99.5%. Rates and 95% confidence intervals of in-hospital events were death 2% (0.7% to 6.1%), myocardial infarction 3% (1% to 7%), coronary bypass surgery 0% (0% to 2.2%), and intracranial hemorrhage 2% (0.4% to 5.3%). Severe thrombocytopenia was observed in 4% of patients (1.4% to 7.8%) after readministration. Allergic or anaphylactic reactions were not observed. Major bleeding was associated with excessive concomitant antithrombotic therapy. Patients undergoing readministration of abciximab within 2 weeks of first administration experienced a higher incidence of severe thrombocytopenia (12% vs. 2%, p = 0.046). Thus, abciximab remains clinically efficacious when readministered as an adjunct to percutaneous coronary intervention. However, concomitant heparin administration must be carefully monitored and warfarin therapy should be avoided. Vigilant surveillance for thrombocytopenia should be employed. Reduced dosing may be necessary when abciximab is readministered within days of the initial administration.

SCAI consensus document on occupational radiation exposure to the pregnant cardiologist and technical personnel

Concerns regarding radiation exposure and its effects during pregnancy are often quoted as an important barrier preventing many women from pursuing a career in Interventional Cardiology. Finding the true risk of radiation exposure from performing cardiac catheterization procedures can be challenging and guidelines for pregnancy exposure have been inadequate. The Women in Innovations group of Cardiologists with endorsement of the Society for Cardiovascular Angiography and Interventions aim to provide guidance in this publication by describing the risk of radiation exposure to pregnant physicians and cardiac catheterization personnel, to educate on appropriate radiation monitoring and to encourage mechanisms to reduce radiation exposure. Current data do not suggest a significant increased risk to the fetus of pregnant women in the cardiac catheterization laboratory and thus do not justify precluding pregnant physicians from performing procedures in the cardiac catheterization laboratory. However, radiation exposure among pregnant physicians should be properly monitored and adequate radiation safety measures are still warranted.

Varenicline for Smoking Cessation in Hospitalized Patients With Acute Coronary Syndrome

Background— Less than one-third of smokers hospitalized with an acute coronary syndrome (ACS) remain abstinent following discharge. We assessed whether varenicline, begun in-hospital, is efficacious for smoking cessation following ACS. Methods and Results— We conducted a multi-center, double-blind, randomized, placebo-controlled trial in which smokers hospitalized with an ACS were randomized to varenicline or placebo for 12 weeks. All patients received low-intensity counseling. The primary end point was point-prevalence smoking abstinence assessed at 24 weeks by 7-day recall and biochemical validation using expired carbon monoxide. A total of 302 patients were randomized (mean age 55±9 years; 75% male; 56% ST-segment elevation myocardial infarction; 38% non-ST-segment elevation myocardial infarction; 6% unstable angina). Patients smoked a mean of 21±11 cigarettes/d at the time of hospitalization and had been smoking for a mean of 36±12 years. At 24 weeks, patients randomized to varenicline had significantly higher rates of smoking abstinence and reduction than patients randomized to placebo. Point-prevalence abstinence rates were 47.3% in the varenicline group and 32.5% in the placebo group (P=0.012; number needed to treat=6.8). Continuous abstinence rates were 35.8% and 25.8%, respectively (P=0.081; number needed to treat=10.0), and rates of reduction ≥50% in daily cigarette consumption were 67.4% and 55.6%, respectively (P=0.05; number needed to treat=8.5). Adverse event rates within 30 days of study drug discontinuation were similar between groups (serious adverse events: varenicline 11.9%, placebo 11.3%; major adverse cardiovascular events: varenicline 4.0%, placebo 4.6%). Conclusions— Varenicline, initiated in-hospital following ACS, is efficacious for smoking cessation. Future studies are needed to establish safety in these patients. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00794573.

Radial Versus Femoral Access for Coronary Angiography/Intervention in Women With Acute Coronary Syndromes: Insights From the RIVAL Trial (Radial Vs femorAL access for coronary intervention).

OBJECTIVES The purpose of this study was to determine the efficacy and safety of radial versus femoral access in women undergoing coronary angiography/intervention. BACKGROUND The risk of bleeding and vascular access site complications are higher in women than in men. METHODS In a pre-specified RIVAL (RadIal Vs femorAL access for coronary intervention) subgroup analysis, we compared outcomes in women (n=1,861) and men (n=5,160) randomized to radial versus femoral access. RESULTS Overall, women were at higher risk of major vascular complications compared with men (4.7% vs. 1.7%; p<0.0001). Major vascular complications were significantly reduced with radial access in women (3.1% vs. 6.1%; hazard ratio [HR]: 0.5; 95% confidence interval [CI]: 0.32 to 0.78; p=0.002) and in men (0.7% vs. 2.8%; HR: 0.27; 95% CI: 0.17 to 0.45; p<0.0001; interaction p=0.092). Crossover rates were higher with radial compared with femoral access in women (11.1% vs. 1.9%; HR: 5.88; p<0.0001) and men (6.3% vs. 1.9%; HR: 3.32; p<0.0001; interaction p=0.054). Percutaneous coronary intervention (PCI) success rates were similar irrespective of access site (women: HR: 1.05; p=0.471; men: HR: 1.00; p=0.888; interaction p=0.674), with no differences in PCI complications. In multivariable analyses, female sex was an independent predictor of major vascular complications (HR: 2.39; 95% CI: 1.76 to 3.25; p<0.0001). There were consistent findings for women and men, with no difference for the primary composite endpoint of death, myocardial infarction, stroke, and non-coronary artery bypass grafting bleeding (women: 3.9% vs. 5.0%; HR: 0.77; 95% CI: 0.50 to 1.19; men: 3.54% vs. 3.5%; HR: 1.00; 95% CI: 0.75 to -1.34; interaction p=0.325). CONCLUSIONS Women undergoing coronary angiography and PCI have a higher risk of vascular access site complications compared with men, and radial access is an effective method to reduce these complications.

Bleeding complications with platelet glycoprotein IIb/IIIa receptor antagonists.

Platelet glycoprotein (GP) IIb/IIIa receptor antagonists are being used with increasing frequency in the settings of percutaneous coronary interventions and acute ischemic syndromes. The development of bleeding complications following GPIIb/IIIa blockade represents a significant limitation to its effectiveness. Baseline characteristics predictive of future bleeding events in patients receiving platelet GPIIb/IIIa receptor antagonist include older age, low body weight, evolving myocardial infarction, and female sex. In patients undergoing percutaneous coronary interventions with adjunctive GPIIb/IIIa inhibition, the risk of bleeding, particularly from the femoral vascular access site, may be reduced through the use of low-dose, weight-adjusted heparin (70 U/kg), avoidance of postprocedural heparin, and early vascular sheath removal. Strategies to reduce the incidence of bleeding complications in patients receiving GPIIb/IIIa inhibitors are proposed in this article.

Comparison of one-year outcomes following coronary artery stenting in diabetic versus nondiabetic patients (from the Enhanced Suppression of the Platelet IIb/IIIa Receptor With Integrilin Therapy [ESPRIT] Trial).

For patients undergoing nonurgent coronary stent implantation, blockade of the glycoprotein IIb/IIIa receptor with eptifibatide reduces the incidence of ischemic complications. We evaluated the interaction of eptifibatide with diabetes in patients who underwent this procedure by analyzing the 1-year outcomes of those enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial (466 diabetic and 1,595 nondiabetic patients). At 1 year, the composite end point of death, myocardial infarction (MI), or target vessel revascuarlization (TVR) was higher in diabetic patients (24.5% vs 18.4%; p = 0.008). At 1 year, eptifibatide had a similar effect on the composite end point of death, MI, or TVR in diabetic (hazards ratio [HR] 0.71, 95% confidence interval [CI] 0.49 to 1.04) and nondiabetic patients (HR 0.80, 95% CI 0.63 to 0.99). A similar treatment effect was also seen on death or MI in both groups. The 1-year mortality rate for diabetic patients assigned to placebo was 3.5% versus 1.3% for patients receiving eptifibatide (HR 0.37, 95% CI 0.10 to 1.41); the latter rate was similar to the mortality rate of 1.4% for nondiabetic patients in the eptifibatide group. However, eptifibatide did not have a significant effect on TVR in diabetic patients (HR 0.90, 95% CI 0.57 to 1.41). Our data suggest that treatment with eptifibatide is associated with a similar relative reduction in adverse ischemic complications in diabetic and nondiabetic patients undergoing coronary stent implantation. There is no evidence of a statistical interaction in the treatment effect of eptifibatide between patients with and without diabetes.