Successful dissolution of occlusive coronary thrombus with local administration of abciximab during PTCA

Intracoronary Administration of Drugs in Clinical Practice

Intracoronary administration of drugs allows to achieve the fastest possible effect in interventional cardiology. This allows to avoid all the biological filters of the body and achieve the required concentration of the active substance at the injection site. Also, given the local action, systemic side effects are nearly absent. The aim. To study the literature data of the leading countries of the world in the field of intracoronary drug administration. To analyze the experience of different centers on the use of various medications in the treatment of the phenomenon of distal microembolization. Results. One of the first drugs administered intracoronary was streptokinase for the treatment of acute myocardial infarction. After that, it became clear that this method of delivering drugs is possible and can be used. With the beginning of the treatment of acute coronary syndromes by stenting, one of the possible complications arose in the form of no-reflow. At the same time, realizing that this is a local problem, they began to use the possibility of intracoronary administration of drugs to treat this phenomenon. The main advantage of this method is quick response to drug administration. Today, the drugs of choice in the treatment of no-reflow are verapamil, adenosine, nitroprusside, adrenaline. On the other hand, probably the most common drug that is administered intracoronary is nitroglycerin. It is used as a vasodilator in the event of spasm of the coronary arteries. Subsequently, it has been recommended to deliver drugs via a microcatheter or aspiration catheter to achieve even more selective effect in the area of the affected vessel, and this also minimizes drug loss due to coronary reflux into the aortic sinuses while usinga guiding catheter. Work is also underway on the use of intracoronary insulin in acute coronary syndrome in order to reduce the area of damage in myocardial infarction. It is also very promising to study the introduction of stem cells directlyinto the myocardium through a microcatheter in order to regenerate the myocardium after a heart attack. Conclusions. Intracoronary administration of drugs allows to achieve the maximum effect in the shortest possible time. Today, many drugs can be used in this way, starting from the treatment of the phenomenon of distal microembolization and ending with myocardial regeneration after myocardial infarction.

Intralesional versus intracoronary administration of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention in patients with acute coronary syndromes: A meta-analysis of randomized controlled trials

BACKGROUND

Glycoprotein IIb/IIIa inhibitors (GPIs) have been regarded as an adjuvant regimen to deal with no-reflow. However, whether intralesional (IL) administration of GPIs improves myocardial reperfusion without increasing bleeding in patients with acute coronary syndrome (ACS) compared with intracoronary (IC) administration has not been well addressed. Our meta-analysis aimed to evaluate the efficacy and safety of IL versus IC administration of GPIs for patients with ACS during percutaneous coronary intervention.

METHODS

We systematically searched Medline, Embase, the Cochrane Central Register of Controlled Trials, and Cambridge Scientific Abstracts from January 2007 to May 2017. Thrombolysis in Myocardial Infarction (TIMI) 3 flow, corrected TIMI frame count (CTFC), and complete ST-segment resolution (>70%) were selected as the primary outcomes. Major adverse cardiac events (MACEs) were the secondary outcome, and major bleeding complications were the safety outcome. Data analysis was conducted using the Review Manager 5.3 software.

RESULTS

Six randomized controlled trials were included in our meta-analysis. Compared with IC, IL obtained better results in terms of TIMI grade 3 flow [odds ratio (OR) 2.29; 95% confidence intervals (CIs) 1.31-4.01; P = .004], CTFC [weighted mean difference (WMD) -4.63; 95% CI -8.82 to -0.43; P = .03], and complete ST-segment resolution (OR 1.55; 95% CI 1.12-2.14; P = .008). There was a trend toward decreased MACE in the IL administration groups, which was not of statistical significance (OR 0.63; 95% CI 0.30-1.31; P = .22). No significant difference was found between the two groups in terms of in-hospital major bleeding events (OR 2.52; 95% CI .66 to 9.62; P = .18).

CONCLUSION

IL administration yielded favorable outcomes in terms of myocardial tissue reperfusion as evidenced by the improved TIMI flow grade, CTFC, complete ST-segment resolution, and decreased MACE without increasing in-hospital major bleeding events. The IL administration of GPIs can be recommended as the preferred regimen to guard against no-reflow.

Intracoronary Administration of Abciximab During Percutaneous Coronary Interventions: Should This Be the Routine and Preferred Approach?

The authors have had experience with administering abciximab as an intracoronary bolus in 96 high-risk patients undergoing percutaneous coronary interventions, specifically in situations in which there was anticipation of a high embolic load from thrombus/plaque burden at the site of the culprit lesion, saphenous vein graft culprit lesion, threatened abrupt closure, developing slow-flow, or no-reflow phenomena with distal embolization. Our uncontrolled data basically substantiate the safety of intracoronary administration of abciximab. The data summarizing the potential superiority of this method of administration of the drug and the likely mechanisms of this effect are summarized. These incite a need for reevaluation of the method of administration of the drug, especially in high-risk percutaneous coronary interventions cases

Randomized evaluation of intralesion versus intracoronary abciximab and aspiration thrombectomy in patients with ST-elevation myocardial infarction: The COCTAIL II trial

BACKGROUND

Thrombus burden and distal embolization are predictive of no-reflow during primary percutaneous coronary intervention (PCI) in patients with acute ST-elevation myocardial infarction (STEMI). We sought to compare the efficacy of pharmacological and catheter-based strategies for thrombus in patients with STEMI and high atherothrombotic burden.

METHODS

Between January 2012 and December 2013, 128 STEMI patients undergoing primary PCI at 5 centers were randomly assigned in a 2 × 2 factorial design to intracoronary (IC) abciximab bolus (via the guide catheter) versus intralesion (IL) abciximab bolus, each with versus without aspiration thrombectomy (AT). Study end points were residual intrastent atherothrombotic burden, defined as the number of cross-sections with residual tissue area >10% as assessed by optical coherence tomography, and indices of angiographic and myocardial reperfusion.

RESULTS

Residual intrastent atherothrombotic burden did not significantly differ with IL versus IC abciximab (median [interquartile range] 6.0 [1-15] vs 6.0 [2-11], P = .806) and with AT versus no aspiration (6.0 [1-13] vs 6.0 [2-12], P = .775). Intralesion abciximab administration was associated with improved angiographic myocardial reperfusion in terms of thrombolysis in myocardial infarction (TIMI) flow (3 [3-3] vs 3 [2-3], P = .040), corrected TIMI frame count (12 ± 5 vs 17 ± 16, P = .021), and myocardial blush grade (3 [2-3] vs 3 [2-3], P = .035). In particular, IL abciximab was associated with higher occurrence of final TIMI 3 flow (90% vs 73.8%, P = .032) and myocardial blush grade 3 (71.6% vs 52.4%, P = .039). Conversely, AT had no significant effect on indices of angiographic or myocardial reperfusion.

CONCLUSIONS

In patients with STEMI and high thrombotic burden, neither IL versus IC abciximab nor AT versus no aspiration reduced postprocedure intrastent atherothrombotic burden in patients with STEMI undergoing primary PCI. However, IL abciximab improved indices of angiographic and myocardial reperfusion compared to IC abciximab, benefits not apparent with AT.

The REFLO-STEMI trial comparing intracoronary adenosine, sodium nitroprusside and standard therapy for the attenuation of infarct size and microvascular obstruction during primary percutaneous coronary intervention: study protocol for a randomised controlled trial

BACKGROUND

Microvascular obstruction (MVO) secondary to ischaemic-reperfusion injury is an important but underappreciated determinant of short- and longer-term outcome following percutaneous coronary intervention (PCI) treatment of ST-elevation myocardial infarction (STEMI). Several small studies have demonstrated a reduction in the degree of MVO utilising a variety of vasoactive agents, with adenosine and sodium nitroprusside (SNP) being most evaluated. However, the evidence base remains weak as the trials have had variable endpoints, differing drug doses and delivery. As such, the results regarding benefit are conflicting.

METHODS

The REperfusion Facilitated by LOcal adjunctive therapy in STEMI (REFLO-STEMI) trial is a multicentre, prospective, randomised, controlled, open label, study with blinded endpoint analysis: Patients presenting within 6 h of onset of STEMI and undergoing planned primary PCI (P-PCI) with TIMI 0/1 flow in the infarct-related artery (IRA) and no significant bystander coronary artery disease on angiography, are randomised into one of three groups: PCI with adjunctive pharmacotherapy (intracoronary adenosine or SNP) or control (standard PCI). All receive Bivalirudin anticoagulation and thrombus aspiration. The primary outcome is infarct size (IS) (determined as a percentage of total left ventricular mass) measured by cardiac magnetic resonance imaging (CMRI) undertaken at 48 to 72 h post P-PCI. Secondary outcome measures include MVO (hypoenhancement within infarct core) on CMRI, angiographic markers of microvascular perfusion and MACE during 1-month follow-up. The study aims to recruit 240 patients (powered at 80% to detect a 5% absolute reduction in IS).

DISCUSSION

The REFLO-STEMI study has been designed to address the weaknesses of previous trials, which have collectively failed to demonstrate whether adjunctive pharmacotherapy with adenosine and/or SNP can reduce measures of myocardial injury (infarct size and MVO) and improve clinical outcome, despite good basic evidence that they have the potential to attenuate this process. The REFLO-STEMI study will be the most scientifically robust trial to date evaluating whether adjunctive therapy (intracoronary adenosine or SNP following thrombus aspiration) reduces CMRI measured IS and MVO in patients undergoing P-PCI within 6 h of onset of STEMI.

TRIAL REGISTRATION

Trial registered 20th November 2012: ClinicalTrials.gov Identifier NCT01747174.

Intracoronary versus intravenous administration of abciximab in patients with acute coronary syndrome: a meta-analysis

BACKGROUND

Abciximab is a widely used adjunctive therapy for acute coronary syndrome (ACS). However, the effect of intracoronary (i.c.) administration of abciximab on cardiovascular events remains unclear when compared with intravenous (i.v.) therapy.

METHODOLOGY AND PRINCIPAL FINDINGS

We systematically searched the Medline, Embase, and Cochrane Central Register of Controlled Trials databases and reference lists of articles and proceedings of major meetings for obtaining relevant literature. All eligible trials included ACS patients who received either i.c. administration of abciximab or i.v. therapy. The primary outcome was major cardiovascular events, and secondary outcomes included total mortality, reinfarction, and any possible adverse events. Of 660 identified studies, we included 9 trials reporting data on 3916 ACS patients. Overall, i.c. administration of abciximab resulted in 45% reduction in relative risk for major cardiovascular events (RR; 95% confidence interval [CI], 24-60%), 41% reduction in RR for reinfarction (95% CI, 7-63%), and 44% reduction in RR for congestive heart failure relative to i.v. therapy (95% CI, 8-66%); however, compared to i.v. therapy, i.c. administration of abciximab had no effect on total mortality (RR, 0.69; 95% CI, 0.45-1.07). No other significant differences were identified between the effect of i.c. abciximab administration and i.v. therapy.

CONCLUSIONS/SIGNIFICANCE

I.c. administration of abciximab can reduce the risk of major cardiovascular events, reinfarction, and congestive heart failure when compared with i.v. therapy.

Intracoronary glycoprotein IIb/IIIa inhibitor infusion via a perfusion coronary catheter to decrease thrombus burden: results from the ClearWay™ Multicenter Registry

OBJECTIVES

This multicenter registry aimed to assess the ClearWay™ (CW) perfusion catheter in reduction of thrombus burden and improvement of the coronary flow during percutaneous coronary intervention (PCI).

BACKGROUND

The presence or development of thrombus during PCI is associated with poor prognosis.

METHODS

The utility of the CW perfusion catheter was assessed in patients who presented with intracoronary thrombus and were subjected to PCI. Data were collected by online survey from 15 US sites. Angiographic assessment of the coronary thrombus burden and the coronary flow after intracoronary infusion of glycoprotein (GP) IIb/IIIa inhibitors via the CW catheter was evaluated at baseline, immediately after infusion, and at the end of the procedure. The cohort included 102 patients; 71.6% presented with ST-elevation myocardial infarction (MI), 21.6% with non-ST-elevation MI, 5.9% with stable angina pectoris, and 2.9% with silent ischemia. The mean cohort age was 59.9±14.5years and comprised mostly of men (72.5%).

RESULTS

GP IIb/IIIa inhibitors were infused via the CW catheter on average 1.1±0.3 times, with a mean pressure of 4.2±2.7atm and a mean infusion time of 55±55s. Following the infusion, Thrombolysis In Myocardial Infarction (TIMI) flow improved by 1° in 71 patients (69.6%) and by 2° in 51 patients (50%), while visible thrombus was reduced by 52% (p<0.001). In the final angiogram, TIMI flow was restored in 90.2% and clearance of a visible thrombus was obtained in 91.8% of the lesions.

CONCLUSION

Intracoronary infusion of GP IIb/IIIa inhibitors via the perfusion CW catheter is associated with significant reduction in thrombus burden and with improvement of the coronary flow in patients presenting or developing thrombus burden during PCI.

Anticoagulant, anti-aggregation and antithrombotic effects of a novel hexapeptide

OBJECTIVES

Hexapeptide is a novel synthetic oligopeptide with a structure similar to that of eptifibatide. This study was designed to investigate the anticoagulant, anti-aggregation, disaggregation and anti-thrombogenesis effects of hexapeptide.

METHODS

The effects of antiplatelet aggregation induced by adenosine diphosphate (ADP), arachidonic acid (AA) and thrombin, and the effect of disaggregation of platelet aggregation induced by ADP were determined. The anticoagulation indexes were determined by different kits.

KEY FINDINGS

Hexapeptide 1 × 10(-5) -1 × 10(-4) m could significantly prolong rabbit blood clotting time, thrombin time, prothrombin time and activated partial thromboplastin enzyme time, and reduce the length, wet weight, dry weight and the index of thrombus in a concentration-dependent manner. Hexapeptide 1 × 10(-4) m decreased platelet adhesion rate by 40.2%. The platelet aggregation inhibition of hexapeptide in dogs and humans was more obvious than in rabbits and rats. The aggregation inhibition rate of 1 × 10(-5) m hexapeptide in dogs, rabbits, rats and humans induced by ADP was 93.9 ± 1.3%, 66.2 ± 1.4%, 76.1 ± 3.2% and 99.8 ± 0.2%, respectively; the 50% inhibitory concentration (IC50) of hexapeptide was 7.24 × 10(-8), 3.24 × 10(-6), 6.61 × 10(-6) and 8.91 × 10(-8) m, respectively. For the aggregation inhibition rate of hexapeptide in dogs, rabbits and humans induced by AA, the IC50 was 1.29 × 10(-9), 1.32 × 10(-6) and 9.33 × 10(-8) m, respectively; the IC50 of aggregation inhibition rates induced by thrombin was 2.88 × 10(-6), >1 × 10(-5) and 4.17 × 10(-6) m, respectively. The disaggregation rate of 1 × 10(-4) m hexapeptide in dog induced by ADP was 68.8 ± 7.4%.

CONCLUSIONS

Hexapeptide has anticoagulant, antiplatelet aggregation, disaggregation and antithrombotic effects in vitro.

The Optimal Route of Administration of the Glycoprotein IIb/IIIa Receptor Antagonist Abciximab During Percutaneous Coronary Intervention; Intravenous Versus Intracoronary

The use of the glycoprotein (GP) IIb/IIIa receptor antagonist Abciximab has over the years become an important part of the anticoagulant regimen in patients with acute coronary syndrome undergoing percutaneous coronary intervention. Abciximab is a potent inhibitor of platelet aggregation and thrombus formation, but other mechanisms, such as suppression of the inflammatory pathways, have also been proposed to contribute to the benefits of Abciximab.

The optimal route of administration, i.e. intravenous versus intracoronary, of the first dose has been questioned, but only tested in small, non-randomised and retrospective studies or studies with short follow-up. No definite conclusion can be made based on these studies.

In this review we present the current knowledge published about the intracoronary administration of Abciximab including the mechanisms behind the potential beneficial effects, and the safety. The emphasis will be on clinical trials rather than on studies on the pharmacological mechanisms, as the latter have been reviewed thoroughly elsewhere.

Our conclusion from this present review is that randomized trials of intracoronary versus intravenous bolus of Abciximab are needed.

Rationale and design of the INFUSE-AMI study: A 2 × 2 factorial, randomized, multicenter, single-blind evaluation of intracoronary abciximab infusion and aspiration thrombectomy in patients undergoing percutaneous coronary intervention for anterior ST-segment elevation myocardial infarction

BACKGROUND

Whether thrombus aspiration and local glycoprotein IIb/IIIa administration reduce infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) has not been established in multicenter studies.

DESIGN

INFUSE-AMI is a multicenter, open-label, controlled, single-blind randomized study enrolling 452 subjects with anterior STEMI and an occluded proximal or mid-left anterior descending artery with thrombosis in myocardial infarction 0, 1, or 2 grade flow undergoing primary PCI with bivalirudin anticoagulation. Subjects are randomized in a 2 × 2 factorial to one of the following 4 arms: (1) local infusion of abciximab using the ClearWay RX Local Therapeutic Infusion Catheter (ClearWay, Atrium Medical Corp, Hudson, NH) after aspiration with a 6F Export Aspiration Catheter (Medtronic, Inc, Minneapolis, MN), (2) local infusion of abciximab using the ClearWay RX Infusion Catheter and no aspiration, (3) no local infusion of abciximab and aspiration with a 6F Export Aspiration Catheter, or (4) no local infusion of abciximab and no aspiration. The primary end point is infarct size (percentage of total left ventricular mass) at 30 days measured by cardiac magnetic resonance imaging. Other secondary end points include microvascular obstruction by cardiac magnetic resonance imaging at 5 days, ST-segment resolution, angiographic myocardial perfusion, thrombus burden, angiographic complications, and clinical events through 1-year follow-up. Safety end points include major and minor bleeding.

SUMMARY

INFUSE-AMI is testing the hypothesis that the intracoronary administration of an abciximab bolus with or without thrombus aspiration before stent implantation compared to no infusion with or without thrombus aspiration reduces infarct size among patients undergoing primary PCI for anterior STEMI who are treated with bivalirudin.

A multicenter randomized study to evaluate intracoronary abciximab with the ClearWay catheter to improve outcomes with Lysis (IC ClearLy): trial study design and rationale

BACKGROUND

Percutaneous coronary intervention (PCI) is a highly effective therapy for acute ST-elevation myocardial infarction. Adjunctive therapy with platelet glycoprotein (GP) IIb/IIIa inhibitor can result in increased vessel patency and improved outcomes in ST-elevation myocardial infarction patients undergoing PCI. The investigation of novel dosing and delivery strategies of this therapy may help to further improve outcomes.

METHODS

IC-Clearly is a randomized, open-label, multicenter trial, with the purpose of evaluating the effectiveness of an intracoronary bolus dose of abciximab delivered using the ClearWay RX catheter vs. an intravenous bolus of abciximab for ST-elevation myocardial infarction with angiographically visible thrombus (thrombus grade >or=2). A total of 150 patients will be randomized 1: 1 to treatment of the culprit artery with intracoronary abciximab (75 patients) or intravenous abciximab (75 patients) in addition to a maintenance infusion regimen of abciximab administered intravenously for 12 h after PCI. The number of patients included in this study is based on the estimation of sample size needed to identify a statistically significant difference in the primary endpoints between the two groups. The primary endpoint chosen to evaluate this hypothesis is infarct size assessed by cardiac magnetic resonance. Clinical outcomes will be assessed for each patient through hospital discharge and at 30-day follow-up.

CONCLUSION

The purpose of this study is to evaluate whether an intracoronary bolus of abciximab delivered with the ClearWay RX catheter prior to the 12 h post-PCI intravenous infusion regimen of abciximab will result in significant additional clot resolution in vivo and improved myocardial perfusion when compared with an intravenous bolus of abciximab on top of the 12 h post-PCI intravenous infusion regimen of abciximab as per standard practice. The primary endpoint chosen to evaluate this hypothesis is infarct size as assessed by cardiac magnetic resonance.

Intracoronary Eptifibatide Bolus Administration During Percutaneous Coronary Revascularization for Acute Coronary Syndromes With Evaluation of Platelet Glycoprotein IIb/IIIa Receptor Occupancy and Platelet Function

Background— Eptifibatide reduces major adverse cardiac events in patients with acute coronary syndromes undergoing percutaneous coronary intervention (PCI). Intracoronary bolus administration of eptifibatide may result in higher levels of platelet glycoprotein IIb/IIIa receptor occupancy in the local coronary bed, disaggregate thrombus in the epicardial artery and microvasculature, and thereby improve coronary flow.

Methods and Results— Patients undergoing PCI for an acute coronary syndrome were randomized to either intracoronary or intravenous bolus administration of eptifibatide. The primary end point was the local glycoprotein IIb/IIIa receptor occupancy measured in the coronary sinus. There were no angiographic, electrophysiological, or other adverse findings attributable to intracoronary eptifibatide. Platelet glycoprotein IIb/IIIa receptor occupancy was significantly greater with intracoronary versus intravenous administration: first bolus, 94±9% versus 51±15% ( P <0.001); and second bolus, 99±2% versus 91±4% ( P =0.001), respectively. Microvascular perfusion was significantly improved as measured by the corrected thrombolysis in myocardial infarction frame count (cTFC) with intracoronary versus intravenous administration: pre-PCI, 36 (median) (25th and 75th percentiles, 16 and 64) versus 31 (25th and 75th percentiles, 23 and 45; P =0.8); and post-PCI, 18 (25th and 75th percentiles, 10 and 22) versus 25 (25th and 75th percentiles, 22 and 35; P =0.007), respectively. The only multivariate predictor associated with a post-PCI cTFC rank score was the first bolus glycoprotein IIb/IIIa receptor occupancy ( P <0.001).

Conclusions— Intracoronary bolus administration of eptifibatide during PCI in patients with acute coronary syndromes results in higher local platelet glycoprotein IIb/IIIa receptor occupancy, which is associated with improved microvascular perfusion demonstrated by an improved cTFC.

Intracoronary versus intravenous abciximab in ST-segment elevation myocardial infarction: rationale and design of the CICERO trial in patients undergoing primary percutaneous coronary intervention with thrombus aspiration

Background

Administration of abciximab during primary percutaneous coronary intervention is an effective adjunctive therapy in the treatment of patients with ST-segment elevation myocardial infarction. Recent small-scaled studies have suggested that intracoronary administration of abciximab during primary percutaneous coronary intervention is superior to conventional intravenous administration. This study has been designed to investigate whether intracoronary bolus administration of abciximab is more effective than intravenous bolus administration in improving myocardial perfusion in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with thrombus aspiration.

Methods/Design

The Comparison of IntraCoronary versus intravenous abciximab administration during Emergency Reperfusion Of ST-segment elevation myocardial infarction (CICERO) trial is a single-center, prospective, randomized open-label trial with blinded evaluation of endpoints. A total of 530 patients with STEMI undergoing primary percutaneous coronary intervention are randomly assigned to either an intracoronary or intravenous bolus of weight-adjusted abciximab. The primary end point is the incidence of >70% ST-segment elevation resolution. Secondary end points consist of post-procedural residual ST-segment deviation, myocardial blush grade, distal embolization, enzymatic infarct size, in-hospital bleeding, and clinical outcome at 30 days and 1 year.

Discussion

The CICERO trial is the first clinical trial to date to verify the effect of intracoronary versus intravenous administration of abciximab on myocardial perfusion in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with thrombus aspiration.

Trial registration

ClinicalTrials.gov NCT00927615

Immediate and intermediate results of intracoronary stand-alone bolus administration of eptifibatide during coronary intervention (ICE) study

BACKGROUND

This study evaluated the immediate and intermediate results of intracoronary (i.c.) eptifibatide administration during percutaneous coronary intervention (PCI). Several studies tested intravenous (i.v.) bolus and continuous administration of eptifibatide during PCI. However, limited data are available regarding giving eptifibatide as i.c. bolus alone during PCI.

METHODS

We studied clinical outcomes of 376 patients who received coronary stent(s) and eptifibatide by 3 applications during PCI and were followed up over 24 months. Group A (119 patients) had i.c. eptifibatide bolus only, group B (119 patients) had i.c. bolus and i.v. infusion, and group C (138 patients) had i.v. bolus and infusion. The standard 2 boluses of eptifibatide 180 microg/kg were given either via i.c. or i.v. route, and only groups B and C received i.v. infusion at 2 microcg x kg(-1) x min(-1) for 18 to 24 hours.

RESULTS

There were 256 males and 120 females, with a mean age of 57 +/- 11 years. Among them, 52% were diabetic. The 6-, 12-, and 24-month cumulative composite end point of death and myocardial infraction was lower in group A (2.5%) compared with group C (10.8%, odds ratio [OR] 4.3, P = .029) and group B (5.8%, OR 2.6, P = .17). Compared with group A, target vessel revascularization was 3-fold in group C (OR 3.3, P = .001) and 2-fold in group B (OR 2.0, P = .061). Bleeding was significantly higher in group C (OR 5.4, P < .0001) and group B (OR 3.4, P = .007) compared with group A. Rehospitalization was significantly lower in group A (10.9%) compared with group B (16.8%) and group C (28%) (P = .0009).

CONCLUSION

The i.c.-bolus-alone application of eptifibatide may be safer and superior to the i.v. route, and continuous infusion may not be necessary. Large-scale prospective randomized trials are needed to further validate these findings.

A sequential approach to the management of a massive intracoronary thrombus in ST elevation myocardial infarction: a case report

Thrombus-laden coronary lesions present a particular challenge to the interventional cardiologist. Despite the development of multiple strategies to attack this problem, lesions with angio-graphically visible thrombus still carry a high risk of complications when coronary intervention is attempted. The authors present a case of acute inferior ST elevation myocardial infarction with a massive thrombus in an ectatic right coronary artery. Sequential treatment with intra-coronary glycoprotein IIb/IIIa inhibitor, rheolytic thrombectomy with 2 different-sized catheters, and transcatheter thrombus aspiration with a Pronto aspiration catheter was required to achieve a satisfactory result. This case illustrates the potential benefit of combining various mechanical strategies to treat intracoronary thrombus.

Rationale for intracoronary administration of abciximab

The present review aims to describe the pharmacological aspects as well as the available clinical data supporting the choice of intracoronary route of administration for abciximab, an antiplatelet drug used in patients with acute coronary syndromes undergoing percutaneous coronary interventions (PCI). Abciximab is a glycoprotein (GP) IIb/IIIa receptor antagonist which determines a potent inhibition of platelet aggregation and thrombus formation. These properties seem to prevent not only thrombus formation but also to promote (at higher drug concentration) lysis of fresh thrombus. Moreover, differently from the other GP IIb/IIIa inhibitors, abciximab also binds to the vitronectin receptor on endothelial, smooth muscle, and inflammatory cells and to an activated conformation of the aMb2 receptor on leukocytes. Such cross-reactivity raises the possibility that clinical benefits derived from its use may not be exclusively due to its anti-thrombotic effect, but may also be related to the suppression of inflammatory pathways involving platelets, white blood cells, and the vascular endothelium. On such basis, the local administration of abciximab at the site of coronary thrombosis may enhance, by increasing its local concentration, the binding to both platelet and endothelium receptors. The results of several angiographic studies assessing the effect of intracoronary abciximab administration support on clinical grounds its adoption in patients with fresh coronary thrombosis. Indeed, better post-angioplasty coronary flow, greater degree of myocardial salvage and a better left ventricular function recovery have been achieved as compared to the intravenous, systemic, administration of drug's bolus. Condensed Abstract Several studies have highlighted the benefits of abciximab, a potent antiplatelet agent, in patients with acute coronary syndromes undergoing percutaneous coronary interventions. Moreover, differently from the other glycoprotein IIb/IIIa receptor antagonists, abciximab also has non-IIb/IIIa-related properties raising the possibility that clinical benefits derived from its use may not be exclusively due to its anti-thrombotic effect, but may also be related to the suppression of inflammatory pathways. Several angiographic studies in patients with fresh coronary thrombosis and recent clinical studies in patients with acute coronary syndromes undergoing mechanical revascularization support the hypothesis that local administration of abciximab at the site of the culprit coronary artery may facilitate both the de-thrombotic and the non-GP IIb/IIIa-dependent properties of the drug. On such basis, the present review aims to describe the pharmacological aspects as well as the available clinical data supporting the choice of intracoronary route of administration for abciximab.

Intracoronary bolus administration of eptifibatide during percutaneous coronary stenting for non ST elevation myocardial infarction and unstable angina

BACKGROUND

Distal embolization of thrombotic debris may occur during and after percutaneous coronary intervention (PCI) for acute coronary syndromes. This may lead to impaired microvascular perfusion, myocardial infarction and increased morbidity and mortality. In vitro studies suggest that high local concentrations of a glycoprotein IIb/IIIa inhibitor may be effective in disaggregating thrombus and thereby prevent microvascular compromise. We hypothesized that intracoronary (IC) administration of eptifibatide during stent implantation for unstable angina/non ST elevation myocardial infarction (UA/NSTEMI) would be safe and would lead to an acceptable rate of normal myocardial perfusion.

METHODS

In 54 patients with UA/NSTEMI, 2 boluses of 180 mcg/kg of eptifibatide each were administered via the IC route during PCI. Data were retrospectively collected and reviewed by an independent core laboratory.

RESULTS

No adverse events including arrhythmias occurred during IC administration of eptifibatide. There were no deaths or urgent revascularizations among patients treated with IC eptifibatide. One patient (2.0%) sustained a post-procedure myocardial infarction. One patient sustained a TIMI major bleeding event due to a gastrointestinal bleed. There were no TIMI minor bleeding events. Normal post PCI TIMI Myocardial Perfusion Grade was observed in 54% of patients.

CONCLUSION

IC bolus administration of eptifibatide was feasible and safe among patients with UA/NSTEMI. Larger prospective and randomized studies are warranted to further explore the efficacy of this strategy. Intracoronary eptifibatide administration during PCI for UA/NSTEMI is feasible and safe.

Angiographic evaluation of the effect of intracoronary abciximab administration in patients undergoing urgent PCI

BACKGROUND

Recent data suggest that the intracoronary (i.c.) administration of a systemic bolus dose of abciximab during PCI may increase the efficacy of this antiplatelet drug. However, the effect of i.c. abciximab on coronary angiographic flow has been not clarified.

METHODS

We studied 37 consecutive patients with acute coronary syndromes (ACS) who underwent successful urgent PCI on the target vessel and were treated by an i.c. abciximab bolus (0.25 mg/kg) prior to the first balloon inflation (Group IC), and 37 matched controls who were treated by intravenous (i.v.) abciximab bolus at the same dose (Group IV). Corrected TIMI frame count (CTFC) in the culprit and in a non-culprit coronary artery branch was assessed before treatment, immediately after intracoronary administration of abciximab bolus and at the end of the procedure.

RESULTS

After administration of abciximab, CTFC significantly decreased from 48+37 to 33+30 (P=0.001) in the culprit vessel while in the non-culprit vessel it remained unchanged (16+7 pre-treatment and 16+7 post-treatment, P=0.68). Final CTFC was 12+4 in Group IC and 14+5 in Group IV (P=0.069). Post-treatment mean peak of the cardiac enzymes showed a trend toward reduction in Group IC compared with Group IV.

CONCLUSIONS

The i.c. administration of abciximab bolus acutely decreases CTFC through culprit vessels of patients with ACS undergoing urgent PCI. Further studies evaluating the potential clinical benefits associated with i.c. abciximab administration are warranted.

Administration of intracoronary eptifibatide during ST-elevation myocardial infarction

Distal embolization of atherothrombotic material during primary percutaneous coronary intervention (PCI) is associated with impaired myocardial perfusion, abnormal left ventricular function, and higher mortality. At high local concentrations, glycoprotein IIb/IIIa receptor antagonists have been demonstrated to promote clot disaggregation in vitro. Intracoronary administration of eptifibatide in vivo may increase local drug concentration by several orders of magnitude and promote clot disaggregation with a minimal increase in systemic drug concentrations. We hypothesized that intracoronary administration of eptifibatide before primary PCI for ST-elevation myocardial infarction would be safe and would be associated with high rates of normal myocardial perfusion. Clinical and angiographic data were pooled from patients who underwent primary PCI and received intracoronary eptifibatide as part of clinical practice. In-hospital adverse events were collected retrospectively. No deaths, urgent revascularizations, or reinfarctions were observed among the 59 patients who were treated with intracoronary eptifibatide. There were no Thrombolysis In Myocardial Infarction (TIMI) major bleeding events. Two TIMI minor bleeding events were noted. Normal TIMI myocardial perfusion grade 3 flow after PCI was noted in 54.4% of patients. No adverse events. including arrhythmias, were noted during intracoronary eptifibatide administration. In conclusion, intracoronary eptifibatide can be administered safely during primary PCI and is associated with few adverse events. Relatively high rates of normal myocardial perfusion were observed after primary PCI with adjunctive intracoronary eptifibatide. Further prospective randomized trials are warranted to evaluate the efficacy and safety of intracoronary eptifibatide.

Acute left main occlusion during percutaneous coronary intervention associated with heparin induced thrombocytopenia with thrombosis syndrome

A 76-year-old male was admitted with Braunwald IIIB unstable angina and treated with intravenous heparin. Coronary angiography 20 days later revealed a severe stenosis in the left circumflex artery. During coronary angioplasty thrombus developed in the circumflex artery, extended in the left main and lead to its occlusion. Normal left coronary artery patency and flow were achieved after intracoronary and intravenous administration of abciximab, and multiple stenting. Platelet-count decrease and an ELISA assay documented the presence of heparin-induced thrombocytopenia with thrombosis syndrome (HITTS). HITTS should be suspected after acute thrombus formation during coronary angioplasty.

Restoration of Normal Coronary Flow With Tirofiban by Intracoronary Administration for No-reflow Phenomenon After Stent Deployment

No-reflow phenomenon is frequently observed during percutaneous coronary intervention in patients with acute coronary syndrome. It may jeopardize hemodynamic status or result in ischemic chest pain in these patients. Currently, there is no adequate solution for this problem. We report our experience with an acute coronary syndrome patient who developed no-reflow phenomenon associated with ST segment elevation and shock after percuteneous coronary balloon dilatation and stent deployment. Intracoronary administration of tirofiban immediately restored the coronary flow of the target vessel, and the disastrous condition reversed. Our experience suggests that intracoronary administration of tirofiban can be considered as an option in case of no-reflow phenomenon during percutaneous coronary intervention.

Comparison of intracoronary vs. intravenous administration of abciximab in coronary stenting

There have been animal and human studies looking at intracoronary (IC) use of abciximab with good short-term clinical outcomes. There exists no data comparing intracoronary with intravenous (IV) administration of abciximab beyond 30 days. We compared the clinical outcomes between the IC (n = 101) and IV (n = 72) group of patients. Patients who had coronary stenting and received abciximab were included in the study. All the patients received the standard systemic bolus dose of abciximab 0.25 mg/kg either via the IC or IV route, followed by a 12-hr IV infusion at 0.125 microg/kg/min. The 6-month composite endpoint of death or myocardial infarction was slightly higher in the IV (13.9%) than in the IC group (5.9%; P = 0.04). The frequency of bleeding complications was similar in both groups. The IC bolus route of abciximab may be superior to the intravenous route. Prospective randomized trials are warranted to validate these findings.

Abciximab, eptifibatide, and tirofiban exhibit dose-dependent potencies to dissolve platelet aggregates

Platelet GPIIb/IIIa antagonists are not only used to prevent platelet aggregation, but also in combination with thrombolytic agents for the treatment of coronary thrombi. Recent data indicate a potential of abciximab alone to dissolve thrombi in vivo. We investigated the potential of abciximab, eptifibatide, and tirofiban to dissolve platelet aggregates in vitro. Adenosine diphosphate (ADP)-induced platelet aggregation could be reversed in a concentration-dependent manner by all three GPIIb/IIIa antagonists when added after the aggregation curve reached half-maximal aggregation. The concentrations chosen are comparable with in vivo plasma concentrations in clinical applications. Disaggregation reached a maximum degree of 72.4% using 0.5 microg/ml tirofiban, 91.5% using 3.75 microg/ml eptifibatide, and 48.4% using 50 microg/ml abciximab (P < 0.05, respectively). A potential fibrinolytic activity of the GPIIb/IIIa antagonists was ruled out by preincubation with aprotinin or by a plasma clot assay. A stable model Chinese hamster ovary (CHO) cell line expressing the activated form of GPIIb/IIIa was used to confirm the disaggregation capacity of GPIIb/IIIa antagonists found in platelets. Not only abciximab, but also eptifibatide and tirofiban have the potential to disaggregate newly formed platelet clusters in vitro. Because enzyme-dependent fibrinolysis does not appear to be involved, competitive removal of fibrinogen by the receptor antagonists is the most likely mechanism.

Abciximab for the treatment of acute distal embolization associated with internal carotid artery angioplasty

Carotid artery angioplasty and stent placement (CAS) can be complicated by procedure-related distal embolization and thrombus formation, potentially resulting in neurological sequelae. Patient A had CAS of left internal carotid artery and had loss of vision in the left eye with no flow in the left ophthalmic artery. Patient B had CAS of right internal carotid artery and developed left sided hemiparesis with total occlusion of the right middle cerebral artery. A selective intra-arterial injection of 5 mg of abciximab locally followed by a bolus of 5 mg of abciximab intravenously resulted in complete resolution of the filling defect on repeat angiography after 10 min in both patients.