Sustained benefit over four years from an initial combined antiplatelet regimen after coronary stent placement in the ISAR trial. Intracoronary Stenting and Antithrombotic Regimen

A randomized clinical trial comparing long-term clopidogrel vs aspirin monotherapy beyond dual antiplatelet therapy after drug-eluting coronary stent implantation: Design and rationale of the Harmonizing Optimal Strategy for Treatment of coronary artery stenosis-Extended Antiplatelet Monotherapy (HOST-EXAM) trial

Percutaneous coronary intervention (PCI) has been developed by drug-eluting stent (DES), but stent implantation has brought the issue of stent thrombosis and optimal antiplatelet therapy. Guidelines recommend at least 6- to 12 months of dual antiplatelet therapy (DAPT) with aspirin and a P2Y₁₂ receptor inhibitor such as clopidogrel. Beyond DAPT after PCI with DES, however, there has been still a debate for antiplatelet regimen. Therefore, we report on the upcoming HOST-EXAM trial (NCT02044250), which will evaluate the efficacy and safety of aspirin and clopidogrel monotherapies beyond DAPT after DES implantation.

TRIAL DESIGN

The HOST-EXAM is a prospective, randomized, open-label, multicenter, comparative effectiveness trial, to compare between clopidogrel (75 mg once daily) and aspirin (100 mg once daily) as long-term antiplatelet agents. A total of 5,530 patients with no clinical events during combined antiplatelet therapy for 12±6 months after index PCI will be screened, enrolled, and randomized to either group (1:1 ratio) receiving antiplatelet monotherapy for 2 years. The primary endpoint will be the rate of clinical events defined as a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission due to acute coronary syndrome, or major bleeding at 24 months after randomization.

CONCLUSIONS

The HOST-EXAM will be the first large-scale randomized controlled study to directly compare the efficacy and safety of long-term antiplatelet monotherapy beyond DAPT after DES implantation. This study will provide clinical evidence to establish optimal regimen for long-term antiplatelet therapy after DES implantation.

Coronary Stenting or Balloon Angioplasty for Chronic Total Coronary Occlusions: The Taiwan Experience (A Single-Center Report)

The authors conducted this study to compare the restenosis and reocclusion rates of primary balloon angioplasty alone versus angioplasty followed by stenting in Taiwanese patients with chronic total occlusions. They also evaluated whether stenting reduced the incidence of restenosis and improved left ventricular function in these patients. From October 1998 to April 2000, a total of 294 patients with chronic total occlusion (Thrombolysis in Myocardial Infarction grade 0 flow) underwent recanalization using balloon angioplasty alone or followed by stent implantation. Of these, only 129 patients were included after procedural failure and patients lost to follow-up; 62 patients were placed in the stent group, while 67 patients were assigned to the percutaneous transluminal coronary angioplasty (PTCA) group. Coronary angiography was performed at baseline and at 6 months follow-up or earlier if angina or objective evidence of ischemia involving the target vessel or other vessels was present. Procedural success was 60%. Minimal lumen diameter increased significantly after stenting: 2.97 ±0.41 vs 2.24 ±0.41 (p<0.001); 60% of patients in the stent group were free of restenosis, whereas only 33% in the PTCA group were free of restenosis at follow-up. Only 1 patient in the stent group had reocclusion, as opposed to 17 (25%) patients in the PTCA group (p<0.001). The follow-up minimal lumen diameter (MLD) at 6 months was significantly larger in the stent group: 1.80 ±0.85 mm vs 1.08 ±0.82 mm (p<0.001). Left ventricular function improved in the stent group, but not in the PTCA group (58.44 ±16.58% to 63.60 ±14.59% [p<0.001] vs 54.13 ±15.66% to 54.31 ±15.60% [p=0.885]). More patients had angina in the PTCA group than in the stented group 43 vs 29 (p=0.053). The postprocedural MLD and reference vessel diameter (RVD) were the strong predictors of restenosis and follow-up MLD (p<0.001). Stenting of chronically occluded arteries significantly reduced the incidence of reocclusion and restenosis, at the same time improving left ventricular function in these patients. This should be the procedure of choice after successful angioplasty of chronically occluded vessels.

Lack of Evidence for Dual Antiplatelet Therapy after Endovascular Arterial Procedures: A Meta-analysis

INTRODUCTION

Dual antiplatelet therapy (DAPT) has mainly replaced mono antiplatelet therapy (MAPT) and is recommended after arterial endovascular revascularization. The aim of this meta-analysis was to summarize the available evidence for DAPT after endovascular revascularization throughout the arterial system.

METHODS

A systematic search was performed in Medline, Embase, and the Cochrane Register. Two reviewers independently performed data extraction and quality assessment using the Cochrane Collaboration risk of bias assessment tool. Included in the search were randomized controlled trials (RCTs) comparing DAPT with MAPT after endovascular procedures for the treatment of coronary, carotid, or peripheral artery disease, reporting at least one clinical outcome. Articles were excluded if patients received anticoagulation in addition to antiplatelet therapy in the post-procedural phase. The primary outcome was restenosis or stent thrombosis, and secondary outcomes were major adverse cardiac events (MACE), target lesion revascularization, cerebrovascular accident or transient ischemic attack, bleeding, and death. Meta-analyses of binary outcomes were performed using the random effects model and described as risk ratios (RRs) and 95% confidence intervals (95% CIs). Chi-square tests were used to test for heterogeneity.

RESULTS

Nine articles were included in this study, involving lower limb peripheral arteries (1), carotid arteries (2), and coronary arteries (6). The pooled results of coronary trials showed a RR for restenosis with DAPT of 0.60 (95% CI 0.28-1.31) and for myocardial infarction 0.49 (95% CI 0.12-2.03). In the carotid artery trials the RR for restenosis was 0.22 (95% CI 0.04-1.20) and for peripheral arteries 1.02 (95% CI 0.56-1.82). A meta-analysis of bleeding risk of all the included trials showed a RR of 1.06 (95% CI 0.32-3.52) with DAPT.

CONCLUSION

The available evidence comparing DAPT with MAPT after endovascular arterial revascularization is limited and the majority of trials were conducted in the cardiology field. No significant evidence for superiority of DAPT compared with MAPT was found, but there was also no evidence of an increased bleeding risk with DAPT over MAPT.

In-hospital outcomes associated with fibrinolytic and thienopyridine use in patients with ST-segment elevation acute myocardial infarction. The global registry of acute coronary events

INTRODUCTION AND OBJECTIVES

To investigate how thienopyridine treatment, with or without associated fibrinolysis, affects the rates of major bleeding and inhospital death in patients with ST-elevation myocardial infarction (STEMI).

METHODS

The rates of major bleeding and in-hospital death were studied in 14,259 consecutive patients with STEMI. During hospitalization, 5340 (38%) received thienopyridines, 3007 (21%) received fibrinolytic drugs, and 2044 (14%) received both.

RESULTS

Major bleeding occurred more frequently in patients who received thienopyridines with or without fibrinolytics, in 4.6% and 4.1%, respectively, compared with 2.3% in those who received fibrinolytics alone and 2.8% in those who received neither (P< .001). Multivariate analysis, which included adjustments for risk factors for bleeding, percutaneous coronary intervention and cardiac catheterization, showed that thienopyridine treatment was an independent risk factor for bleeding (odds ratio=1.68; 95% confidence interval, 1.23-2.31). In-hospital mortality was lower in patients who received a thienopyridine, and such treatment was an independent predictor of lower mortality (odds ratio=0.50; 95% confidence interval, 0.39-0.60).

CONCLUSIONS

Thienopyridine treatment was associated with an increased risk of major bleeding but also with a better in-hospital prognosis. These findings in unselected patients with STEMI, who are representative of those seen in daily clinical practice, complement, but do not replace, the data obtained in randomized clinical trails of selected patients.

Improved long-term survival associated with stent deployment during percutaneous coronary interventions: results from a registry of 3399 patients

INTRODUCTION

The use of stents in percutaneous coronary intervention (PCI) improves procedural success and reduces restenosis. However, few studies have had a sufficient sample size or adequate follow-up to determine whether this advantage results in a positive effect on mortality.

METHODS

A total of 3399 patients undergoing PCI (stented [with dual antiplatelet therapy]: n = 2456, nonstented [balloon PCI or rotational atherectomy]: n = 942) at a single institution from 1994 to 2001 were followed up prospectively (43 +/- 22 and 54 +/- 25 months, respectively) for acute and long-term clinical outcomes.

RESULTS

Angiographic success (< 50% residual stenosis) (99.7% vs 97.7%, P < .001) and acute gain (3.02 +/- 0.55 vs 2.08 +/- 0.62 mm, P < .001) were both greater for stented lesions. Likewise, procedural complications of death (0.04% vs 0.4%, P = .02) and dissection (4.9% vs 8.0%, P = .001) were lower in the stent group, as were rates of 6-month clinical restenosis (10.3% vs 16.3%, P < .001). Eight-year mortality (12.0% vs 18.2%, hazard ratio = 0.78, P = .009) was lower among the stent group, as was long-term major adverse cardiac events (36.2% vs 50.6%, P < .001), but no difference in long-term myocardial infarction was found (6.5% vs 7.6%, P = .28). In multivariable Cox regression, stent use (hazard ratio = 0.76, 95% CI [0.58-0.99], P = .04) remained associated with significantly reduced mortality.

CONCLUSION

This large prospective study demonstrates that, in addition to a general improvement in procedural success and a reduced need for repeat revascularization, the use of stents with dual antiplatelet therapy was associated with a significant reduction in long-term mortality. Consideration should be given for the use of stents whenever feasible during PCI.

Triple antiplatelet therapy during percutaneous coronary intervention is associated with improved outcomes including one-year survival: results from the Do Tirofiban and ReoProGive Similar Efficacy Outcome Trial (TARGET)

OBJECTIVE

We sought to examine if clopidogrel treatment initiated before coronary stenting improved clinical outcomes among patients receiving aspirin and a glycoprotein (GP) IIb/IIIa inhibitor.

BACKGROUND

Antiplatelet therapy plays a pivotal role in contemporary percutaneous coronary interventions (PCI).

METHODS

Outcomes among 4,809 patients randomized to tirofiban or abciximab during PCI with stent placement were compared according to whether they received 300 mg of clopidogrel before PCI (93.1%) versus immediately after the procedure.

RESULTS

The 30-day primary composite end point (death, myocardial infarction [MI], or urgent target vessel revascularization [TVR]) was lower among clopidogrel-pretreated patients (6.6% vs. 10.4%, p = 0.009), mainly because of reduction of MI (6.0% vs. 9.5%, p = 0.012). The benefit of clopidogrel pretreatment was sustained at six months (death, MI, any TVR: 14.6% vs. 19.8%, HR = 0.71, p = 0.010), and this was due mainly to lowering of death and MI (7.8% vs. 13.0%, p = 0.001). At one year, clopidogrel pretreatment was associated with a lower mortality rate (1.7% vs. 3.6%, p = 0.011). Because clopidogrel pretreatment was not randomized, multivariable and propensity analyses were performed. After adjusting for baseline heterogeneity, clopidogrel pretreatment was an independent predictor for death or MI at 30 days (HR = 0.63, p = 0.012) and at six months (HR = 0.61, p = 0.003), and survival at one year (HR = 0.53, p = 0.044). No excess in 30-day bleeding events was noted with clopidogrel pretreatment.

CONCLUSIONS

Among patients undergoing coronary stent placement with aspirin and a GP IIb/IIIa inhibitor, clopidogrel pretreatment is associated with a reduction of death and MI irrespective of the type of GP IIb/IIIa inhibitor used.

Reperfusion in acute myocardial infarction: current concepts

Myocardial reperfusion is the treatment of choice in acute myocardial infarction. Pharmacological thrombolysis restores coronary artery patency in about two thirds of patients with acute myocardial infarction. However, mechanical reperfusion with primary angioplasty and stenting achieves higher patency rates with less complications, especially in high-risk patients. Adjunctive pharmacotherapy and new device technology may improve the outcome of primary angioplasty. Facilitated angioplasty using a combination of half-dose thrombolysis, platelet glycoprotein IIb/IIIa antagonists, and early intervention, appears to be a promising strategy for the treatment of acute myocardial infarction in the modern era. The efficacy and safety of this approach are currently evaluated in several ongoing trials.