Clinical benefits of adjunctive tirofiban therapy in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Effects of Tirofiban in Patients with Acute Myocardial Infarction and Diabetes Mellitus undergoing Primary Percutaneous Coronary Intervention

OBJECTIVE

This study evaluated the efficacy and safety of early vs. late tirofiban administration in the treatment of patients with acute ST-elevation myocardial infarction (STEMI) and diabetes mellitus (DM) undergoing primary percutaneous coronary intervention (pPCI).

METHODS

120 patients with STEMI and DM treated with pPCI were randomly divided into an observation group (n=60) and a control group (n=60). The observation group and the control group were intravenously injected with a bolus of tirofiban preoperatively or intraoperatively, respectively; both groups were then given an intravenous infusion over 24 h at 0.15 μg/kg/min. Thrombolysis in myocardial infarction (TIMI) grade flow, myocardial perfusion index, and functional heart parameters, as well as major adverse cardiovascular events and bleeding, were compared between the two groups.

RESULTS

Functional heart parameters, including left ventricular ejection fraction and cardiac output, were significantly improved in the observation group 6 months after discharge. Thrombus aspiration, inflammatory factors, and cardiac troponin I (cTNI) were more significantly decreased in the observation group than in the control group. The sum-ST-segment elevation at 2 h after pPCI treatment in the observation group was better than that in the control group. There was no significant difference in the incidence of adverse reactions and bleeding between the two groups.

CONCLUSION

The administration of tirofiban before reperfusion therapy compared with after reperfusion therapy is more effective in reducing the hyperthrombotic load, thrombus aspiration, inflammatory factors, and cTNI and can effectively improve myocardial perfusion and heart function.

Routine Glycoprotein IIb/IIIa Inhibitor Therapy in ST-Segment Elevation Myocardial Infarction: A Meta-analysis

BACKGROUND

Guidelines recommend adjunct glycoprotein IIb/IIIa inhibitors (GPIs) only in selected patients with acute ST-segment elevation myocardial infarction (STEMI). This study aimed to evaluate routine GPI use in STEMI treated with primary percutaneous coronary intervention.

METHODS

Online databases were searched for randomized controlled trials of routine GPI vs control therapy in STEMI. Data from retrieved studies were abstracted and evaluated in a comprehensive meta-analysis. Twenty-one randomized controlled trials with 8585 patients were included: 10 trials randomized tirofiban, 9 abciximab, 1 trial eptifibatide, and 1 trial used abciximab+tirofiban; only 1 trial used dual antiplatelet therapy with prasugrel/ticagrelor.

RESULTS

Routine GPI use was associated with a significant reduction in all-cause mortality at 30 days (2.4% [GPI] vs 3.2%; risk ratio [RR], 0.72; P = 0.01) and 6 months (3.7% vs 4.8%; RR, 0.76; P = 0.02), and a reduction in recurrent myocardial infarction (1.1% vs 2.1%; RR, 0.55; P = 0.0006), repeat revascularization (2.5% vs 4.1%; RR, 0.63; P = 0.0001), thrombolysis in myocardial infarction flow <3 after percutaneous coronary intervention (5.4% vs 8.2%; RR, 0.61; P < 0.0001), and ischemic stroke (RR, 0.42; P = 0.04). Major (4.7% vs 3.4%; RR, 1.35; P = 0.005) and minor bleedings (7.2% vs 5.1%; RR, 1.39; P = 0.006) but not intracranial bleedings (0.1% vs 0%; RR, 2.7; P = 0.37) were significantly increased under routine GPI.

CONCLUSIONS

Routine GPI administration in STEMI resulted in a reduction in mortality, driven by reductions in recurrent ischemic events-however predominantly in pre-prasugrel/ticagrelor trials. Trials with contemporary STEMI management are needed to confirm these findings.

Antithrombotic therapy before, during and after emergency angioplasty for ST elevation myocardial infarction

The first three hours after symptom onset hold the maximum potential for myocardial reperfusion and salvage in ST-elevation myocardial infarction (STEMI) patients. During this period timely primary percutaneous coronary intervention (PPCI) or, when PPCI is not promptly feasible, pre-hospital administration of fibrinolyis or a glycoprotein IIb/IIIa-inhibitor (GPI) have been shown to restore coronary patency and reperfusion and even result in myocardial infarction (MI) abortion. On the other hand, oral antiplatelet therapy may not yet guarantee sufficient platelet inhibition. Patients presenting after this golden time have less, if any, benefit from an aggressive antithrombotic treatment prior to PPCI. Antithrombotic treatment during primary angioplasty should be tailored on the basis of the coronary thrombotic burden, vascular approach and the patient's risk of bleeding complications. A GPI-based approach may be favourable in patients presenting early with large MI and high thrombus burden, whereas a bivalirudin-based approach without GPI may be preferred in patients with higher bleeding risk. There are no data to support the use of GPI in bailout conditions. The powerful oral P2Y₁₂ inhibitors, prasugrel and ticagrelor, have been clearly shown to prevent stent thrombosis and recurrent ischaemic events after emergency percutaneous coronary intervention in STEMI patients. Open issues remaining are the treatment of patients with high bleeding risk, such as the elderly and those requiring anticoagulation, as well as the duration of dual antiplatelet therapy after STEMI.

Intracoronary administration of anisodamine and nicorandil in individuals undergoing primary percutaneous coronary intervention for acute inferior myocardial infarction: A randomized factorial trial

In acute inferior myocardial infarction (AIMI), numerous conventional drugs that are used to improve the myocardial microcirculation can significantly reduce blood pressure (BP) and coronary perfusion pressure, aggravate bradyarrhythmia and cause a deterioration in the hemodynamic state of the whole body, which greatly limits the application of these drugs in clinical settings. The aim of the present study was to assess the effect of anisodamine and nicorandil regimens on the prevention of no-reflow (NR) and the amelioration of myocardial reperfusion in patients with AIMI undergoing primary percutaneous coronary intervention (PCI). A total of 104 consecutive patients with AIMI were included in this study and randomly assigned to one of four groups: A (control group), B (anisodamine group), C (nicorandil group) and D (anisodamine and nicorandil group). Patients underwent PCI via transradial artery access and the angiographic results were evaluated. Coronary diastolic BP (DBP) and systolic and mean BPs were measured by invasive catheterization. The primary end-point was a post-PCI Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade (TMPG) of 3. Composite end-points (mortality + new MI + target vessel revascularization) were evaluated during the hospital stay and 30 days after discharge. Following the procedure, the proportion of patients achieving TMPG 3 was significantly higher in group D than that in the other groups (P=0.014); furthermore, the incidence of a postprocedural TIMI score of 3 was the highest in group D. Three days after the procedure, the peak creatine kinase-MB and cardiac troponin I levels were the lowest and the left ventricular ejection fraction was the highest in group D. A thrombus score of 3/4 and low DBP were the independent risk factors for poor myocardial reperfusion (expressed as TMPG <3), while 2 mg anisodamine plus 2 mg nicorandil prior to PCI was protective for optimal myocardial reperfusion following the procedure. The combination of anisodamine and nicorandil can effectively ameliorate myocardial reperfusion and protect cardiac function in patients with AIMI undergoing primary PCI.

The effects of tirofiban infusion on clinical and angiographic outcomes of patients with STEMI undergoing primary PCI

Objective:

The present study was designed to determine the effects of tirofiban (Tiro) infusion on angiographic measures, ST-segment resolution, and clinical outcomes in patients with STEMI undergoing PCI. Glycoprotein (GP) IIb/IIIa inhibitors are beneficial in ST-segment elevation myocardial infarction (STEMI) patients undergoing percutaneous coronary intervention (PCI), while the most effective timing of administration is still under investigation.

Methods:

A total of 1242 patients (83.0% males, mean (standard deviation; SD) age: 54.7 (10.9) years) with STEMI who underwent primary PCI were included in this retrospective non-randomized study in four groups, composed of no tirofiban infusion [Tiro (-); n=248], tirofiban infusion before PCI (pre-Tiro; n=720), tirofiban infusion during PCI (peri-Tiro; n=50), and tirofiban infusion after PCI (post-Tiro; n=224). In all Tiro (+) patients, bolus administration of Tiro (10 pg/kg) was followed by infusion (0.15 pg/kg/min) for a mean (SD) duration of 22.4±6.8 hours.

Results:

The pre-PCI Tiro group was associated with the highest percentage of patients with TIMI 3 flow (99.4%; p<0.001), the lowest corrected TIMI frame count [21(18-23.4); p<0.001], the highest percentage of patients with >75% ST-segment resolution (78.1%; p<0.001), and the lowest rate of in-hospital sudden cardiac death and in-hospital all-cause mortality (3.2%, p<0.05, 3.3%, p=0.01). Major bleeding was reported in 18 (1.8%) patients who received tirofiban.

Conclusion:

Use of standard-dose bolus tirofiban in addition to aspirin, high-dose clopidogrel, and unfractionated heparin prior to primary PCI significantly improves myocardial reperfusion, ST-segment resolution, in-hospital mortality rate, and in-hospital sudden cardiac death in patients with STEMI with no increased risk of major bleeding.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Glycoprotein IIb/IIIa inhibitors with or without thienopyridine pretreatment improve outcomes after primary percutaneous coronary intervention in high-risk patients with ST elevation myocardial infarction--a meta-regression of randomized controlled trials

BACKGROUND

Recent studies have casted a doubt on usefulness of routine glycoprotein IIb/IIIA inhibitors (GPI) in patients, pretreated with aspirin and clopidogrel, undergoing primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI).

OBJECTIVE

We aimed to investigate the effect of relevant factors, particularly thienopyridine pretreatment, on clinical benefit from GPI in randomized controlled trials (RCT).

METHODS

We searched electronic databases for RCT comparing GPI to control in patients with STEMI undergoing primary PCI. Relevant study covariates and clinical outcomes were extracted. A random effect cumulative and subgroup analyses (thienopyridine non-pretreated studies vs. pretreated studies) were performed. A weighted random effect meta-regression to determine the effect of thienopyridine pretreatment, enrollment year, control group mortality, and ischemic time on mortality benefit from GPI use was conducted.

RESULTS

Twenty studies (9 non-pretreated, 11 pretreated) with a total of 7,414 patients (3,811 GPI, 3,603 control) were included. GPI use reduces mortality (risk ratio, RR = 0.75 95% confidence interval (CI) 0.57-0.97, P = 0.03), target vessel revascularization (TVR) (RR = 0.63, 95% CI 0.50-0.80, P = 0.0002), but not reinfarction (RR = 0.66, 95% CI 0.44-1.0, P = 0.05) at 30 days. There was no effect of thienopyridine pretreatment on reduction in mortality (P = 0.39), reinfarction (P = 0.46), or TVR (P = 0.95) in subgroup analysis. Meta-regression analyses showed significant effect of control group mortality risk (B = -12.15, P = 0.034) but not of thienopyridine pretreatment, enrollment year or control group ischemic time on mortality reduction from GPI use.

CONCLUSION

The benefit from GPI use in primary PCI for STEMI appears to depend on mortality risk, and not on thienopyridine pretreatment.

Detection of coronary microembolization by Doppler ultrasound in patients with stable angina pectoris during percutaneous coronary interventions under an adjunctive antithrombotic therapy with abciximab: design and rationale of the High Intensity Transient Signals ReoPro (HITS-RP) study

Background

Embolization of atherosclerotic debris from the rupture of a vulnerable atherosclerotic plaque occurs iatrogenically during percutaneous coronary interventions (PCI) and can induce myocardial necrosis. These microembolizations are detected as high intensity transient signals (HITS) using intracoronary Doppler technology.

Presentation of the hypothesis

In the presented study we will test if abciximab (ReoPro®) infusion reduces high intensity transient signals in patients with stable angina pectoris undergoing PCI in comparison to standard therapy alone.

Testing the hypothesis

The High Intensity Transient Signals ReoPro® (HITS-RP) study will enroll 60 patients. It is a prospective, single center, randomized, double-blinded, controlled trial. The study is designed to compare the efficacy of intravenous abciximab administration for reduction of microembolization during elective PCI. Patients will be randomized in a 1:1 fashion to abciximab or placebo infusion. The primary end point of the HITS-RP-Study is the number of HITS during PCI measured by intracoronary Doppler wire. Secondary endpoints are bleeding complications, elevation of cardiac biomarkers or ECG changes after percutaneous coronary interventions, changes in coronary flow velocity reserve, hs-CRP elevation, any major adverse cardio-vascular event during one month follow-up.

Implications of the hypothesis

The HITS-RP-Study addresses important questions regarding the efficacy of intravenous abciximab administration in reducing microembolization and periprocedural complications in stable angina pectoris patients undergoing PCI.

Trial registration

The trial is registered under http://www.drks-neu.uniklinik-freiburg.de/drks_web/:DRKS00000603.

Treatment with tirofiban for acute coronary syndrome (ACS): a systematic review and network analysis

OBJECTIVE

To assess the efficacy of tirofiban in comparison to usual care or other GPIIb/IIIa antagonists (eptifibatide and abciximab). Results were analysed by drug administration with planned percutaneous coronary intervention (PCI) or as medical management without planned PCI, and separately for STEMI or NSTE ACS patients.

RESEARCH DESIGN AND METHODS

A systematic review was performed of randomized controlled trials of tirofiban, abciximab, eptifibatide or usual care given to patients with acute coronary syndrome. Nine databases were searched up to March 2010. Pair-wise meta-analysis was used to combine all available direct comparisons; indirect comparisons and network analysis were performed when this was not possible. The primary outcome was MACE (major adverse cardiac event).

RESULTS

The search yielded 8, 119 records and 50 trials were included (total number of patients = 52,958). Compared to usual care, high and medium-dose tirofiban (25 and 10 µg/kg/min) administered with planned PCI reduced MACE at 30 days for patients with STEMI (RR 0.67, 95% CI 0.45, 0.99; RR 0.28, 95% CI 0.10, 0.80), but was not effective as a medical management. Medium-dose tirofiban (10 µg/kg/min) administered with planned PCI or low dose (0.4 µg/kg/min) as medical management reduced the risk of MACE for patients with NSTE ACS (RR 0.39, 95% CI 0.21, 0.75; RR 0.58, 95% CI 0.41, 0.83) in comparison to usual care, but at the expense of increased thrombocytopenia (RR 3.26, 95% CI 1.31, 8.13). Evidence from RCTs and network analysis indicated tirofiban and abciximab were equally effective and safe. Comparing tirofiban and eptifibatide treatment by indirect and network analysis produced inconclusive results.

CONCLUSIONS

Tirofiban was more effective than usual care for STEMI and NSTE ACS patients receiving planned PCI, and NSTE ACS patients receiving medical management. Tirofiban and abciximab were equally effective. Comparisons of tirofiban and eptifibatide were inconclusive.

Effect of delayed vs immediate stent implantation on myocardial perfusion and cardiac function in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous intervention with thrombus aspiration

BACKGROUND

Optimizing microcirculation in STEMI patients with thrombus-containing lesion undergoing percutaneous coronary intervention (PCI) remains challenging. Our objective was to compare the effects on myocardial perfusion and cardiac function of delayed vs immediate stent implantation after thrombus aspiration in STEMI patients undergoing PCI.

METHODS

Eighty-seven STEMI patients with thrombus-containing lesion undergoing PCI were enrolled. After thrombus aspiration was performed, subjects were divided into 2 groups according to residual thrombus score (TS): immediate stent implantation (ISI) group (n = 47, residual TS < 2; stenting was performed immediately), and delayed stent implantation (DSI) group (n = 40, residual TS ≥ 2; stenting was performed 7 days later). Corrected thrombolysis in myocardial infarction frame count and myocardial blush grade were analyzed immediately after PCI. The wall motion score index was assessed on admission and at 6-month follow-up.

RESULTS

At the end of the PCI procedure, the corrected thrombolysis in myocardial infarction frame count was significantly shorter and the myocardial blush grade 3 was more frequent in the DSI group than in the ISI group. Compared with the ISI group, the DSI group had a lower incidence of thrombus-related angiographic events, including distal embolization and no reflow. A significantly greater improvement in wall motion score index from baseline to 6-month follow-up was observed in the DSI group compared with the ISI group.

CONCLUSIONS

In STEMI patients presenting with thrombus containing lesion undergoing PCI, delayed stent implantation after thrombus aspiration leads to better myocardial perfusion and cardiac functional recovery in comparison with immediate stent implantation.

Beneficial effects of intracoronary tirofiban bolus administration following upstream intravenous treatment in patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention: the ICT-AMI study

BACKGROUND

We investigated whether an additional intracoronary tirofiban bolus administration following upstream intravenous treatment could further improve myocardial reperfusion and clinical outcome in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

METHODS

A total of 453 eligible STEMI patients were randomly allocated to intracoronary bolus administration of tirofiban (10 μg/kg; n=229) or saline (10 mL; n=224) during primary PCI, followed by intravenous tirofiban infusion (0.15 μg/kg/min) for 24-36 h. Serum levels of P-selectin, vWF, CD40L and serum amyloid A (SAA) in the coronary sinus were measured before and after intracoronary bolus administration. The primary endpoint was ST-segment resolution (STR) at 90 min after the procedure. Second endpoints included corrected TIMI frame count (cTFC), left ventricular volumes and ejection fraction (EF), and major adverse cardiac events (MACE) at 30-day and 6-month follow-up.

RESULTS

Intracoronary tirofiban administration resulted in a higher rate of completed STR (59.0% vs. 44.6%, P=0.002), lower cTFC (21.6±5.4 vs. 23.7±7.8, P=0.048), and significantly reduced coronary sinus levels of P-selectin, vWF, CD40L and SAA. Patients treated with intracoronary tirofiban had a trend toward less MACE at 30 days (3.1% vs. 6.7%, P=0.072). At 6 months, left ventricular end-systolic volume was smaller, EF was higher and MACE-free survival was improved (96.1% vs. 90.6%, P=0.020) in the intracoronary tirofiban group.

CONCLUSIONS

An additional intracoronary tirofiban bolus administration following upstream intravenous treatment reduces coronary circulatory platelet activation and inflammatory process, and significantly improves myocardial reperfusion and left ventricular function as well as 6-month MACE-free survival for STEMI patients undergoing primary PCI.

Tirofiban use with clopidogrel and aspirin decreases adverse cardiovascular events after percutaneous coronary intervention for ST-elevation myocardial infarction: a meta-analysis of randomized trials

Current guidelines deemed usefulness of routine early glycoprotein IIb/IIIa inhibitor (GPI) administration in ST-elevation myocardial infarction (STEMI) before primary percutaneous coronary intervention (PCI) with dual antiplatelet therapy as uncertain. We aimed to examine the current evidence for the use of tirofiban, a nonpeptide glycoprotein IIb/IIIa inhibitor, in STEMI patients treated with dual antiplatelet therapy. We performed systematic searches of MEDLINE, EMBASE, and CENTRAL databases for randomized controlled trials (RCTs) of tirofiban use in STEMI patients treated with aspirin and clopidogrel which reported clinical and/or angiographic outcomes after primary PCI. Data were combined using random effect and fixed effect models for heterogeneous and homogeneous outcomes respectively using Review Manager 5 (The Nordic Cochrane Centre, The Cochrane Collaboration, 2008). Six randomized controlled trials were eligible for the inclusion; involving 708 patients in tirofiban group and 721 control subjects. Routine tirofiban use decreased the major adverse cardiovascular events (odds ratio [OR] 0.50; 95% confidence interval [CI], 0.26-0.94). Corrected thrombolysis in myocardial infarction (TIMI) frame count was also reduced with tirofiban (mean difference -8.48 [95% CI, -12.62 to -4.34]). There were no significant differences in the rates of postprocedure TIMI flow grade 3 and TIMI myocardial perfusion/blush grade 3, major bleeding by TIMI criteria, or mortality in the 2 groups. Current analysis of available studies suggests that routine and early tirofiban use before primary PCI may decrease the major cardiovascular events in STEMI patients treated with aspirin and clopidogrel without any significant increase in major bleeding. An adequately powered randomized trial is urgently needed to confirm the above findings and estimate the effect size.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (Issue 3, 2009), MEDLINE (1966 to October 2009), and EMBASE (1980 to October 2009).

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

Forty-eight trials involving 62,417 patients were included. During PCI, IIb/IIIa blockers decreased mortality at 30 days (OR 0.76, 95% CI 0.62 to 0.95) and at six months (OR 0.84, 95% CI 0.71 to 1.00). Death or MI was decreased both at 30 days (OR 0.65, 95% CI 0.60 to 0.72), and at 6 months (OR 0.70, 95% CI 0.61 to 0.81), although severe bleeding was increased (OR 1.38, 95% CI 1.20 to 1.59; absolute risk increase (ARI) 8.0 per 1000). The efficacy results were homogeneous for every endpoint according to the clinical condition of the patients, but were less marked for patients pre-treated with clopidogrel, especially in patients without ACS.As initial medical treatment of NSTEACS, IIb/IIIa blockers did not decrease mortality at 30 days (OR 0.91, 95% CI 0.80 to 1.03) or at six months (OR 1.00, 95% CI 0.87 to 1.15), but slightly decreased death or MI at 30 days (OR 0.92, 95% CI 0.86 to 0.99) and at six months (OR 0.88, 95% CI 0.81 to 0.96), although severe bleeding was increased (OR 1.27, 95% CI 1.12 to 1.43; ARI 1.4 per 1000).

AUTHORS' CONCLUSIONS

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

Upstream vs deferred administration of small-molecule glycoprotein IIb/IIIa inhibitors in primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: insights from randomized clinical trials

BACKGROUND

Recent data have demonstrated similar outcomes for patients with ST-segment elevation myocardial infarction (STEMI) who undergo primary percutaneous coronary intervention (PCI) and are treated with small-molecule glycoprotein IIb/IIIa inhibitors (smGPIs) compared with those treated with abciximab. In the present study, a meta-analysis was performed to evaluate the relative safety and efficacy of upstream vs deferred administration of smGPIs in STEMI patients.

METHODS AND RESULTS

A total of 10 randomized clinical trials comparing upstream vs deferred administration of smGPIs in 2,724 patients were located in the electronic databases of the published literature. Preprocedural Thrombolysis In Myocardial Infarction Study (TIMI) grade 2 or 3 flow was present in 45.0% of the upstream group compared with 36.9% in the deferred group (odds ratio (OR) 1.40, P<0.001). However, no difference in post-procedural TIMI 3 flow (OR 0.87, P=0.25) was found between the groups. The 30-day mortality rate in the upstream group did not differ from that of the deferred group (OR 1.04, P=0.85). No significant difference was noted with respect to major bleeding complications (OR 1.25, P=0.38).

CONCLUSIONS

In STEMI patients scheduled for primary PCI, although early smGPIs treatment improved initial epicardial patency, no beneficial effect on post-procedural angiographic or 30-day clinical outcome was found. Thus, the current available data do not support the routine utilization of upstream smGPIs in STEMI patients treated with primary PCI.

Early administration of small-molecule glycoprotein IIb/IIIa inhibitors before primary percutaneous coronary intervention for ST-elevation myocardial infarction: insights from randomized clinical trials

BACKGROUND

Current guidelines recommend abciximab (ReoPro) as an adjunctive pharmacologic agent to primary percutaneous coronary intervention (PPCI) for patients with ST-segment elevation myocardial infarction (STEMI). However, small-molecule glycoprotein IIb/IIIa receptor inhibitors (smGPIs), such as tirofiban (aggrastat) and eptifibatide (integrilin), are more commonly used in clinical practice.

METHOD AND RESULT

We performed a meta-analysis to compare the safety and efficacy of early administration of smGPIs versus abciximab before PPCI. The literature was scanned by formal searches of electronic databases from January 1990 to April 2009. A total of 4 randomized trials meeting the prespecified criteria were analyzed, involving 2040 patients. Rates of initial Thrombolysis in Myocardial Infarction Study (TIMI) 3 flow before procedure as well as complete ST resolution after PPCI were not inferior in smGPIs group compared with abciximab group (odds ratio [OR] 1.12, P = .31; and OR 1.05, P = .66, respectively). There was no significant difference in the risk of 30-day (OR 0.83, P = .54) or 8-month mortality (OR 0.78, P = .43) between smGPI and abciximab group. With regard to the safety end points, neither the major nor the minor bleeding complications in smGPIs group differed significantly from those in abciximab group (OR 1.32, P = .43; and OR 0.82, P = .37, respectively).

CONCLUSION

This meta-analysis shows that early administration of smGPIs is as effective as abciximab in the setting of PPCI for STEMI, without an increase in bleeding complications.

Coronary microembolization: from bedside to bench and back to bedside

Coronary microembolization from the erosion or rupture of a vulnerable atherosclerotic plaque occurs spontaneously in acute coronary syndromes and iatrogenically during percutaneous coronary interventions. Typical consequences of coronary microembolization are microinfarcts with an inflammatory response, contractile dysfunction, and reduced coronary reserve. Apart from transient elevations of creatine kinase and troponin, microemboli can be visualized by intracoronary Doppler and the resulting microinfarcts by late-enhancement nuclear magnetic resonance. Statins, antiplatelet agents, and coronary vasodilators protect against microembolization and microinfarction when started before percutaneous coronary interventions. Distal protection devices can retrieve atherothrombotic debris and prevent its embolization into the microcirculation, but their effect on clinical outcome has been disappointing so far, except for saphenous vein bypass grafts. Devices for aspiration of thrombi and thrombus-derived vasoconstrictor, thrombogenic, and inflammatory substances, however, reduce thrombus burden, improve perfusion, and provide protection in patients with acute myocardial infarction.