Effects of P2Y12 receptor inhibition with or without aspirin on hemostatic system activation: a randomized trial in healthy subjects

Randomized evaluation of 5-month Ticagrelor monotherapy after 1-month dual-antiplatelet therapy in patients with acute coronary syndrome treated with drug-coated balloons: REC-CAGEFREE II trial rationale and design

BACKGROUND

Patients treated with drug-coated balloons (DCB) have the theoretical advantage of adopting a low-intensity antiplatelet regimen due to the absence of struts and polymers. Nevertheless, the optimal antiplatelet strategy for patients undergoing DCB-only treatment remains a topic of debate and has not been investigated in randomized trials.

METHODS

The REC-CAGEFREE II is an investigator-initiated, prospective, open-label, multi-center, randomized, non-inferiority trial aimed to enroll 1908 patients from ≥ 40 interventional cardiology centers in China to evaluate the non-inferiority of an antiplatelet regimen consisting of Aspirin plus Ticagrelor for one month, followed by five months Ticagrelor monotherapy, and then Aspirin monotherapy for six months (Experimental group) compared to the conventional treatment of Aspirin plus Ticagrelor for 12 months (Reference group) in patients with acute coronary syndrome (ACS) who have undergone percutaneous coronary intervention (PCI) using paclitaxel-coated balloons (DCB) exclusively. Participants will be randomly assigned to the Experimental or Reference group in a 1:1 ratio. The randomization will be stratified based on the center and the type of lesion being treated (De novo or in-stent restenosis). The primary endpoint is net adverse clinical events (NACE) within 12 months of PCI, which includes the composite of all-cause death, any stroke, any myocardial infarction, any revascularization and Bleeding Academic Research Consortium (BARC) defined type 3 or 5 bleeding. The secondary endpoint, any ischemic and bleeding event, which includes all-cause death, any stroke, MI, BARC-defined type 3 bleeding, any revascularization, and BARC-defined type 2 bleeding events, will be treated as having hierarchical clinical importance in the above order and analyzed using the win ratio method.

DISCUSSION

The ongoing REC-CAGEFREE II trial aims to assess the efficacy and safety of a low-intensity antiplatelet approach among ACS patients with DCB. If non-inferiority is shown, the novel antiplatelet approach could provide an alternative treatment for ACS patients with DCB.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT04971356.

Tailoring antiplatelet therapy in older patients with coronary artery disease

The older population represents a unique subset of patients due to a higher rate of comorbidities and risk factors, which can lead to a higher rate of ischemic and bleeding events. As a result, older adults are mainly underrepresented or excluded from randomized trials. Although the advancement in the percutaneous coronary intervention field with the development of new technologies, techniques, and potent antiplatelet therapy led to a reduction of ischemic risk, there is still a concern regarding bleeding hazards. Apart from the global utilization of less invasive trans-radial approach and proton pump inhibitors to reduce bleeding risk, proper tailoring of antiplatelet therapy in the older person is imperative. So far, several antiplatelet drugs have been introduced in different clinical scenarios, with dual antiplatelet therapy (combination of acetylsalicylic acid and P2Y12 inhibitor) recommended after percutaneous coronary intervention. The decision on the choice of antiplatelet drug and the DAPT duration is challenging and should be based on the relationship between ischemia and bleeding with the purpose of reducing ischemic events but not at the expense of increased bleeding complications. This is particularly important in the older population, where the evidence is obscure. The main objective of this review is to summarize the available evidence on contemporary antiplatelet therapy and different approaches of de-escalation strategies in older patients after percutaneous coronary intervention.

Efficacy and safety of dual antiplatelet therapy after percutaneous coronary drug-eluting stenting: A network meta-analysis

BACKGROUND

To evaluate the efficacy and safety of dual antiplatelet regimens after coronary drug-eluting stenting by network meta-analysis (NMA).

METHODS

PubMed, The Cochrane Library, Embase, and Web of Science databases were electronically searched to collect randomized controlled trials (RCTs) of the comparison of different dual antiplatelet regimens after coronary drug-eluting stenting from inception to September 1st, 2021. Two reviewers independently screened literature, extracted data, and assessed the risk bias of included studies. Stata 16.0 software was used for NMA.

RESULTS

A total of 27 RCTs involving 79,880 patients were included. The results of NMA: in terms of myocardial infarction (MI), other 3 interventions were higher than the long-term dual antiplatelet therapy (L-DAPT) (the standard dual antiplatelet therapy [Std-DAPT] [odds ratio [OR] = 1.82, 95%confidence interval [CI]: 1.49-2.21), the aspirin monotherapy after short-term dual antiplatelet therapy (S-DAPT + As) (OR = 2.06, 95%CI: 1.57-2.70), the P2Y12 inhibitor monotherapy after short-term dual antiplatelet therapy (S-DAPT + P2Y12) (OR = 1.71, 95%CI: 1.29-2.28)]. In terms of stent thrombosis, other 3 interventions were higher than L-DAPT [Std-DAPT (OR = 2.18, 95%CI: 1.45-3.28), S-DAPT + As (OR = 2.32, 95%CI: 1.52-3.54), S-DAPT + P2Y12 (OR = 2.31, 95%CI: 1.22-4.36)]. There was no statistically significant difference among the 4 interventions in prevention of stroke and all-cause mortality (P > .05). In terms of cardiovascular and cerebrovascular adverse events, other 3 interventions were higher than L-DAPT (Std-DAPT [OR = 1.28, 95%CI: 1.12-1.45], S-DAPT + As [OR = 1.27, 95%CI: 1.09-1.48], S-DAPT + P2Y12 [OR = 1.24, 95%CI: 1.01-1.52]). In terms of safety, bleeding rate of other 3 interventions were lower than L-DAPT (Std-DAPT [OR = 0.67, 95%CI: 0.52-0.85], S-DAPT + As [OR = 0.51, 95%CI: 0.39-0.66], S-DAPT + P2Y12 [OR = 0.36, 95%CI: 0.26-0.49]). Two interventions were lower than L-DAPT (S-DAPT + As [OR = 0.77, 95%CI: 0.65-0.90], S-DAPT + P2Y12 [OR = 0.54, 95%CI: 0.44-0.66]). S-DAPT + As was higher than L-DAPT (OR = 1.42, 95%CI: 1.10-1.83).

CONCLUSIONS

S-DAPT + P2Y12 has the lowest bleeding risk, while L-DAPT has the highest bleeding risk. In the outcome of MI, stent thrombosis, and cardiovascular and cerebrovascular adverse events, L-DAPT has the best efficacy. In the outcome of stroke and all-cause mortality, the 4 interventions were equally effective.

The Optimal Strategy of Dual Antiplatelet Therapy after Percutaneous Coronary Intervention with Drug-Eluting Stent

Objective: To test the optimal strategy of dual antiplatelet therapy (DAPT) after implantation of drug-eluting stents (DESs) according to specific DAPT time and subsequent monotherapy. Methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase, and Web of Science to identify randomized controlled trials (RCTs). Six DAPT strategies were compared: 1-month DAPT followed by P2Y12 inhibitor monotherapy, 3-month DAPT followed by P2Y12 inhibitor monotherapy, 3-month DAPT followed by aspirin monotherapy, 6-month DAPT followed by aspirin monotherapy, 12-month DAPT, and >12-month DAPT. Pooled odd ratios (ORs) with 95% credible intervals (CrIs) were calculated to summarize the effect of each strategy tested. Results: We identified 24 RCTs containing 81,405 patients. In comparison with 12-month DAPT, 3-month DAPT followed by P2Y12 inhibitor monotherapy reduced net clinical events (OR: 0.72; CrI: 0.55−0.94). Major bleeding (OR: 0.57; CrI: 0.34−1.00) was marginally decreased without impact on ischemic events (OR: 0.93; CrI: 0.68−1.29). Moreover, the benefits of 3-month DAPT (P2Y12 inhibitor) were consistent for male patients with acute coronary disease, young age, complex lesion, single-vessel disease, low body mass index, and without diabetes. Although >12-month DAPT was associated with a lower risk of myocardial infarction (OR: 0.67; CrI: 0.51−0.93), the risk of major bleeding (OR: 1.70; CrI: 1.10−2.70) was increased. Conclusion: Among patients treated with DESs, 3-month DAPT followed by P2Y12 inhibitor monotherapy may be the optimal antiplatelet strategy, while DAPT beyond 1 year reduces myocardial infarction at the expense of increased major bleeding.

Ticagrelor Monotherapy After PCI in High-Risk Patients With Prior MI: A Prespecified TWILIGHT Substudy

OBJECTIVES

The aim of this study was to evaluate if patients with prior myocardial infarction (MI) could benefit from ticagrelor monotherapy in terms of bleeding reduction without any compromise in ischemic event prevention.

BACKGROUND

Patients with history of MI who undergo percutaneous coronary intervention (PCI) remain at risk for recurrent ischemic events. The optimal antithrombotic strategy for this cohort remains debated.

METHODS

In this prespecified analysis of the randomized TWILIGHT (Ticagrelor With Aspirin or Alone in High-Risk Patients after Coronary Intervention) trial, the authors evaluated the impact of history of MI on treatment effect of ticagrelor monotherapy versus ticagrelor plus aspirin in patients undergoing PCI with drug-eluting stent with at least 1 clinical and 1 angiographic high-risk feature and free from adverse events at 3 months after index PCI. The primary endpoint was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding, and the key secondary endpoint was the composite of all-cause death, MI, or stroke, both at 12 months after randomization.

RESULTS

A total of 1,937 patients (29.7%) with and 4,595 patients (70.3%) without prior MI were randomized to ticagrelor and placebo or ticagrelor and aspirin. At 1 year after randomization, patients with prior MI experienced higher rates of death, MI, or stroke (5.7% vs 3.2%; P < 0.001) but similar BARC types 2 to 5 bleeding (5.0% vs 5.5%; P = 0.677) compared with patients without prior MI. Ticagrelor monotherapy consistently reduced the risk for the primary bleeding outcome in patients with (3.4% vs 6.7%; HR: 0.50; 95% CI: 0.33-0.76) and without (4.2% vs 7.0%; HR: 0.58; 95% CI: 0.45-0.76; P_interaction = 0.54) prior MI. Rates of the key secondary ischemic outcome were not significantly different between treatment groups irrespective of history of MI (prior MI, 6.0% vs 5.5% [HR: 1.09; 95% CI: 0.75-1.58]; no prior MI, 3.1% vs 3.3% [HR: 0.92; 95% CI: 0.67-1.28]; P_interaction = 0.52).

CONCLUSIONS

Ticagrelor monotherapy is associated with significantly lower risk for bleeding events compared with ticagrelor plus aspirin, without any compromise in ischemic prevention, among high-risk patients with history of MI undergoing PCI. (Ticagrelor With Aspirin or Alone in High-Risk Patients After Coronary Intervention [TWILIGHT]; NCT02270242).

Single antiplatelet therapy with use of prasugrel in patients undergoing percutaneous coronary intervention

OBJECTIVES

We aimed to assess the ischemic and bleeding risks of single antiplatelet therapy (SAPT) with prasugrel compared with standard dual antiplatelet therapy (DAPT) (aspirin plus clopidogrel for 1 year) in patients with chronic coronary syndrome (CCS) treated with new generation drug-eluting stents (DES).

BACKGROUND

To date, data on SAPT with potent P2Y12 inhibitors in the absence of aspirin immediately after PCI are limited.

METHODS

Between January 2009 and November 2019, all CCS patients undergoing percutaneous coronary intervention (PCI) enrolled to the Bern PCI registry were considered for analysis. We performed propensity score matching in a 1:4 fashion to compare patients who received SAPT with prasugrel versus standard DAPT. The primary ischemic endpoint was a composite of cardiovascular death, myocardial infarction, and stroke and the primary bleeding endpoint was BARC 3 or 5 bleeding, both assessed at 1 year.

RESULTS

After propensity score matching, the final study population consisted of 225 patients with SAPT and 889 with DAPT. There was no significant difference in rates of the primary ischemic (5.2% vs. 4.2%, p = .50) or the primary bleeding (1.5% vs. 2.0%, p = .60) endpoints between groups. SAPT was not associated with an increased risk of definite stent thrombosis (0.9% vs. 0.8%, p = .83).

CONCLUSIONS

Among selected CCS patients undergoing PCI with DES, SAPT with prasugrel was not associated with an excess of ischemic events compared with standard DAPT. No difference in bleeding was observed either. The results may serve as the basis for larger trials assessing the potential benefits and risks of SAPT.

Safety and efficacy of very short dual antiplatelet therapy followed by P2Y12 inhibitor monotherapy in older patients undergoing percutaneous coronary intervention: meta-analysis of randomised controlled trials

BACKGROUND

older patients undergoing percutaneous coronary intervention (PCI) represent a growing population sharing both a high ischemic and bleeding risk. Dual antiplatelet therapy (DAPT) reduces the incidence of thrombotic events but exposes patients to an increased risk of bleeding and subsequent mortality. Its optimal duration after PCI remains unclear.

OBJECTIVE

to assess the impact of short-duration DAPT on both bleeding and ischemic events in the specific population of older patients undergoing PCI.

METHODS

we performed a meta-analysis of randomised controlled trials comparing the safety and efficacy of standard versus very short duration (≤ 3 months, followed by P2Y12 inhibitor monotherapy) DAPT after PCI with a drug-eluting stent in older patients.

RESULTS

four studies, representing 8,961 older patients, were finally included. Compared with standard duration, short-duration DAPT was associated with similar rates of major bleeding (relative risks, RR 0.70 [0.47; 1.05]) and the composite efficacy endpoint (RR 0.85 [0.63; 1.14]). There was a high level of heterogeneity between the studies (I2 = 68%) regarding major bleeding.

CONCLUSION

our meta-analysis suggests that short DAPT may be a valid option in older patients after PCI but it also highlights the need for specific studies in such patients on optimal duration of antiplatelet therapy.

P2Y12 Inhibitor Monotherapy Versus Conventional Dual Antiplatelet Therapy or Aspirin Monotherapy in Acute Coronary Syndrome: A Pooled Analysis of the SMART-DATE and SMART-CHOICE Trials

Controversy remains regarding the optimal antiplatelet regimen in patients with acute coronary syndrome (ACS). This study sought to investigate the efficacy and safety of P2Y12 inhibitor monotherapy compared with conventional dual antiplatelet therapy (DAPT) and aspirin monotherapy in patients with ACS undergoing percutaneous coronary intervention. Data on 4,453 patients were pooled from SMART-DATE and SMART-CHOICE randomized trials. Antiplatelet therapy regimens were categorized as P2Y12 inhibitor monotherapy (P2Y12 inhibitor monotherapy after 3-month DAPT), conventional DAPT (12-month or longer DAPT), and aspirin monotherapy (aspirin monotherapy after 6-month DAPT). The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE, a composite of all-cause death, myocardial infarction, and stroke). Inverse-probability of treatment-weighted (IPTW) analysis was performed. At 1 year, patients in the P2Y12 inhibitor monotherapy had a comparable risk of MACCE compared with those in the conventional DAPT (IPTW-adjusted hazard ratio [HR], 0.655; 95% confidence interval [CI] 0.393 to 1.094; p = 0.106), and tended to have a lower risk of MACCE than those in the aspirin monotherapy (IPTW-adjusted HR, 0.606; 95% CI, 0.347 to 1.058; p = 0.078). The adjusted hazard for the Bleeding Academic Research Consortium (BARC) type 2 to 5 bleeding was significantly lower in P2Y12 inhibitor monotherapy than in conventional DAPT (IPTW-adjusted HR, 0.341; 95% CI, 0.190 to 0.614; p < 0.001) and in aspirin monotherapy (IPTW-adjusted HR, 0.359; 95% CI, 0.182 to 0.708; p = 0.003). In conclusion, among patients with ACS undergoing PCI, P2Y12 inhibitor monotherapy after 3-month DAPT reduced risk of bleeding compared with conventional DAPT and aspirin monotherapy after 6-month DAPT without increasing MACCE.

Effect of aspirin treatment duration on clinical outcomes in acute coronary syndrome patients with early aspirin discontinuation and received P2Y12 inhibitor monotherapy

Recent clinical trials showed that short aspirin duration (1 or 3 months) in dual antiplatelet therapy (DAPT) followed by P2Y12 inhibitor monotherapy reduced the risk of bleeding and did not increase the ischemic risk compared to 12-month DAPT in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). However, it is unclear about the optimal duration of aspirin in P2Y12 inhibitor monotherapy. The purpose of this study was to evaluate the influence of aspirin treatment duration on clinical outcomes in a cohort of ACS patients with early aspirin interruption and received P2Y12 inhibitor monotherapy. From January 1, 2014 to December 31, 2018, we included 498 ACS patients (age 70.18 ± 12.84 years, 71.3% men) with aspirin stopped for various reasons before 6 months after PCI and received P2Y12 inhibitor monotherapy. The clinical outcomes between those with aspirin treatment ≤ 1 month and > 1 month were compared in 12-month follow up after PCI. Inverse probability of treatment weighting was used to balance the covariates between groups. The mean duration of aspirin treatment was 7.52 ± 8.10 days vs. 98.05 ± 56.70 days in the 2 groups (p<0.001). The primary composite endpoint of all-cause mortality, recurrent ACS or unplanned revascularization and stroke occurred in 12.6% and 14.4% in the 2 groups (adjusted HR 1.19, 95% CI 0.85-1.68). The safety outcome of BARC 3 or 5 bleeding was also similar (adjusted HR 0.69, 95% CI 0.34-1.40) between the 2 groups. In conclusion, patients with ≤ 1 month aspirin treatment had similar clinical outcomes to those with treatment > 1 month. Our results indicated that ≤ 1-month aspirin may be enough in P2Y12 inhibitor monotherapy strategy for ACS patients undergoing PCI.

Dual Antiplatelet Therapy De-escalation Strategies

Dual antiplatelet therapy (DAPT), the combination of aspirin (ASA), and a P2Y₁₂ inhibitor, protects against stent thrombosis and new atherothrombotic events after a stent implantation or an acute coronary syndrome, but exposes patients to an increased risk of bleeding. In most current practices, the P2Y₁₂ inhibitor is stopped at 6 to 12 months and ASA is continued indefinitely. The advent of safer stents, with less risk of stent thrombosis, has challenged this standard of care, however. A number of alternative strategies involving earlier de-escalation of the antiplatelet therapy have therefore been proposed. In these approaches, standard DAPT is switched to a less potent antithrombotic combination at an earlier time-point than recommended by guidelines. Three different de-escalation variations have been tested to date. The first one maintains DAPT but switches from the potent P2Y₁₂ inhibitors ticagrelor or prasugrel to either a lower dose or to clopidogrel, while maintaining ASA. The 2 other approaches involve changing DAPT to a single antiplatelet at some earlier time-point after the percutaneous coronary intervention procedure, by stopping either the P2Y₁₂ inhibitor or ASA. These strategies have all demonstrated some benefit in clinical trials so far, but especially the contribution of ASA in secondary prevention is clearly evolving as its role in increasing bleeding complications while not providing increased ischemic benefit is becoming more and more clear. In contemporary practice, the type and duration of DAPT should now be based on an individualized decision, and the de-escalation strategies, if used wisely, can be added to the existing options.

Impact of Transcatheter Aortic Valve Implantation on Thrombin Generation and Platelet Function

BACKGROUND

 Transcatheter aortic valve implantation (TAVI) is an evolving treatment of severe aortic valve stenosis. However, thromboembolic events such as stroke are common, predominantly early after TAVI. Optimal periprocedural antithrombotic regime is unknown. Especially, as antithrombotic medication enhances bleeding risk, thrombin generation and platelet function are crucial in the pathogenesis of ischemic events. However, the impact of the TAVI procedure on thrombin formation and platelet reactivity is not known by now.

METHODS

 We evaluated thrombin levels using thrombin-antithrombin (TAT) complexes and prothrombin fragments (PTFs) using enzyme-linked immunosorbent assay. Furthermore, platelet reactivity was measured via light transmission aggregometry before and 2 hours after TAVI in 198 patients.

RESULTS

 TAT complexes and PTF F1 + 2 substantially increased during TAVI. Postprocedurally, TAT complexes and PTF were significantly higher after TAVI compared with percutaneous coronary intervention due to acute myocardial infarction, while preprocedural TAT complexes and PTF F1 + 2 did not differ. In contrast, platelet reactivity was not altered early after TAVI. Only adenosine diphosphate-induced aggregation was reduced, reflecting preprocedural loading with clopidogrel.

CONCLUSION

 In this pilot study, we were able to demonstrate that thrombin generation is significantly increased early after TAVI, while platelet function is not affected. Increased thrombin concentrations may contribute to the high risk of postprocedural thromboembolic events. This leads to the hypothesis that extended peri-interventional anticoagulation early after TAVI may be an approach to reduce thromboembolic events.

A case-control study indicates that coagulation imbalance is associated with arteriosclerosis and markers of endothelial dysfunction in kidney failure

Endothelial dysfunction, one of many causes of arterial changes in end-stage kidney disease (kidney failure), is a likely link between early vascular aging and the risk of thrombosis or bleeding in this condition. To evaluate this, we compared links between arterial stiffness and endothelial/coagulation factors in 55 patients receiving hemodialysis therapy and 57 age-/sex-matched control individuals. Arterial stiffness was assessed from carotid-femoral pulse wave velocity, and coagulation status from the endogenous thrombin generating potential. Markers of endothelial dysfunction (von Willebrand factor, tissue factor pathway inhibitor), neutrophil extracellular traps and tissue factor-positive extracellular vesicles were higher in patients with kidney failure. Prothrombin fragments 1 and 2, and D-dimer markers of in vivo coagulation activation were also higher. However, in vitro in the presence of platelets, endogenous thrombin generating potential was lower and its downregulation by activated protein C impaired. Antiplatelet drugs did not affect these parameters. In multiple regression analysis, prothrombin fragments 1 and 2, D-dimer, factor VIII and monocyte-derived tissue factor-positive extracellular vesicles correlated with higher carotid-femoral pulse wave velocity. In patients with kidney failure, in vivo hypercoagulability occurred with reduced thrombin generation in platelet-rich plasma, likely explaining the opposing thrombotic and bleeding tendencies in patients with kidney failure. Importantly, arteriosclerosis is more closely related to a prothrombotic state. Thus, coagulation changes plus arterial stiffness highlight a major therapeutic challenge for anticoagulant and antiplatelet drug use.

P2Y12 inhibitor monotherapy and dual antiplatelet therapy after percutaneous coronary intervention: An updated meta-analysis of randomized trials

INTRODUCTION

Long-term dual antiplatelet therapy (DAPT) has substantially reduced the risk of post-percutaneous coronary intervention (PCI) myocardial infarction and stent thrombosis at the expense of major bleeding. We hypothesized that a short-term DAPT followed by extended P2Y₁₂ inhibitor monotherapy might be appropriate for patients with both high ischemic and bleeding risks.

MATERIALS AND METHODS

We searched the databases: Pubmed, EMBASE, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov to identify randomized trials assessing the antiplatelet strategies after PCI. The primary safety endpoint was Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding. The efficacy outcome was a composite of all-cause mortality/cardiovascular disease (CVD) death, myocardial infarction, or stroke. A random-effect model was used to calculate the pooled hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

We identified 5 randomized trials comparing P2Y₁₂ inhibitor monotherapy with standard DAPT (12 months) (16,057 versus 16,088). P2Y₁₂ inhibitor monotherapy following short-term DAPT (1 to 3 months) significantly reduced the risk of BARC type 3 or 5 bleeding compared to standard DAPT (pooled HR: 0.63, 95%CI: 0.46-0.86). The difference between P2Y₁₂ inhibitor monotherapy and standard DAPT in reducing the composite CVD outcomes was not statistically significant (HR: 0.88, 95%CI: 0.77-1.01).

CONCLUSIONS

P2Y₁₂ inhibitor monotherapy might be an effective strategy for lowering severe bleeding complications and simultaneously preserving the ischemic benefit in patients receiving PCI.

Differential Effects of Clopidogrel With or Without Aspirin on Platelet Reactivity and Coagulation Activation: A Randomized Trial in Healthy Volunteers

Dual antiplatelet therapy (DAPT) is standard in acute coronary syndrome but confers a bleeding risk. To compare effects of clopidogrel single antiplatelet therapy (SAPT) with clopidogrel-based DAPT on hemostatic system activation we conducted a randomized clinical trial in 44 volunteers (clopidogrel (d1: 600 mg, d2-6: 150 mg) ± aspirin (100 mg)). Multiple electrode aggregometry-adenosine diphosphate (MEA-ADP) and MEA-arachidonic acid (MEA-AA) triggered aggregometry, vasodilator-stimulated phosphoprotein (VASP), beta thromboglobulin, p-selectin, thromboxane B₂ , d-Dimer, prothrombin fragment 1.2 (f1.2), and a phospholipid-dependent clotting time were measured in venous blood. Changes are described by mean differences (Δmean (95% confidence interval (CI)) or geometric mean ratios (95% CI)). DAPT and SAPT comparably and significantly decreased MEA-ADP at 2 hours (-60% vs. -63%; P = 0.35, Δmean -4.9, 95% CI -15.4 to 5.5). At 24 hours (-59% vs. -47%, P = 0.04, Δmean -11.1, 95% CI -21.7 to -0.4]) and 8 days (-61% vs. -53%, P = 0.04, Δmean -11.3, 95% CI -22.0 to -0.6). Both treatments significantly reduced VASP and MEA-AA after 2 hours and 8 days. DAPT inhibited MEA-AA significantly stronger at 2 hours (-77% vs. -30%; P < 0.0001, Δmean -39.6, 95% CI -54.2 to -25.0), at 24 hours (-80% vs. -27%, P < 0.0001, Δmean -47.8, 95% CI -62.3 to -33.3), and 8 days (-79% vs. -27%, P < 0.0001, Δmean -48.9, 95% CI -62.5 to -35.4). Neither treatment significantly influenced beta thromboglobulin or p-selectin. DAPT abolished and SAPT reduced thromboxane B₂ after 24 hours and 8 days. The d-Dimer was reduced by DAPT (0.94, 95% CI 0.89-1.00, P = 0.04) at 2 hours but not after 24 hours and 8 days. SAPT did not decrease d-Dimer. Neither treatment affected f1.2. DAPT and SAPT comparably affect platelet and coagulation activation in venous blood.

Abbreviated Dual Antiplatelet Therapy Followed by P2Y12 Inhibitor Monotherapy versus 12 Months' Dual Antiplatelet Therapy Post Percutaneous Coronary Intervention: A Systematic Review and Meta-analysis of Randomized Controlled Trials

INTRODUCTION

An increased incidence of stent thrombosis after implantation of first-generation drug-eluting stents led to a recommendation of dual antiplatelet therapy (DAPT) for 12 months after the procedure. However, given the use of second-generation and newer drug-eluting stents, this recommendation needs to be revisited. Several randomized controlled trials (RCTs) have studied an abbreviated DAPT regimen of ≤ 3 months followed by P2Y₁₂ inhibitor monotherapy, and results have been conflicting.

OBJECTIVE

We performed a systematic review with meta-analysis of RCTs of abbreviated DAPT for ≤ 3 months followed by P2Y₁₂ monotherapy compared with 12 months of DAPT.

METHODS

We performed a systematic search of the MEDLINE/PubMed, Cochrane, and DARE (Database of Abstracts of Reviews of Effects) databases for eligible RCTs. Quantitative analysis was performed based on the intention-to-treat principle. We used the Mantel-Haenszel method with a random-effects model to calculate relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

The final analysis included four RCTs. We found no difference in the risk of all-cause mortality (RR 0.90; 95% CI 0.77-1.05; p = 0.18; I² = 0%; χ²p = 0.58), myocardial infarction (RR 0.99; 95% CI 0.86-1.15; p = 0.85; I² = 0%; χ²p = 0.70), stroke (RR 1.14; 95% CI 0.65-1.98; p = 0.65; I² = 59%; χ²p = 0.06), or stent thrombosis (RR 0.98; 95% CI 0.73-1.33; p = 0.90; I² = 0%; χ²p = 0.48). Additionally, there was no difference in the risk for major bleeding, defined as BARC (Bleeding Academic Research Consortium) type 3 or 5, between the two groups (RR 0.62; 95% CI 0.37-1.05; p = 0.07; I² = 79%; χ²p < 0.05).

CONCLUSION

Abbreviated DAPT followed by P2Y₁₂ monotherapy resulted in a similar risk of re-ischemic clinical outcomes post percutaneous coronary intervention as compared with the standard 12-month DAPT regimen. The risk of major bleeding (BARC type 3 or 5) also remained similar between the two groups. However, as trials have reported benefits with abbreviated DAPT followed by P2Y₁₂ monotherapy in terms of combined endpoints and all bleeding (BARC type 2-5), additional research is needed.

P2Y12 inhibitors monotherapy after short course of dual antiplatelet therapy in patients undergoing percutaneous coronary intervention: a meta-analysis of randomized clinical trials including 29 089 patients

AIMS

Dual antiplatelet therapy (DAPT) reduces the incidence of thrombotic complications at the cost of an increase in bleedings. New antiplatelet therapies focused on minimizing bleeding and maximizing antithrombotic effects are emerging. The aim of this study is to collect the current evidence coming from randomized controlled trials (RCTs) on early aspirin interruption after percutaneous coronary intervention (PCI) and current drug-eluting stent (DES) implantation and to perform a meta-analysis in order to evaluate the safety and efficacy of this strategy.

METHODS AND RESULTS

MEDLINE/PubMed was systematically screened for RCTs comparing P2Y12 inhibitors (P2Y12i) monotherapy after a maximum of 3 months of DAPT (S-DAPT) vs. DAPT for 12 months (DAPT) in patients undergoing PCI with DES. Baseline features were appraised. Major adverse cardiac and cerebrovascular events (MACCE: all causes of death, myocardial infarction, and stroke) and its single composites, stent thrombosis (ST) and Bleeding Academic Research Consortium (BARC) type 3 or 5 were considered and pooled with fixed and random-effects with inverse-variance weighting. A total of four RCTs including a total of 29 089 patients were identified. Overall, the majority of included patients suffered a stable coronary artery disease, while ST-elevation myocardial infarction was the least represented clinical presentation. Complex anatomical settings like left main intervention, bifurcations, and multi-lesions treatment were included although representing a minor part of the cases. At 1-year follow-up, MACCE rate was similar [odds ratio (OR) 0.90; 95% confidence intervals (CIs) 0.79-1.03] and any of its composites (all causes of death rate: OR 0.87; 95% CIs 0.71-1.06; myocardial infarction: OR 1.06; 95% CIs 0.90-1.26; stroke: OR 1.12; 95% CIs 0.82-1.53). Similarly, also ST rate was comparable in the two groups (OR 1.17; 95% CIs 0.83-1.64), while BARC 3 or 5 bleeding resulted significantly lower, adopting an S-DAPT strategy (OR 0.70; 95% CIs 0.58-0.86).

CONCLUSION

After a PCI with current DES, an S-DAPT strategy followed by a P2Y12i monotherapy was associated with a lower incidence of clinically relevant bleeding compared to 12 months DAPT, with no significant differences in terms of 1-year cardiovascular events.

Meta-Analysis of the Efficacy and Safety of P2Y12 Inhibitor Monotherapy After Short Course of Dual-Antiplatelet Therapy in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

Guidelines recommend dual antiplatelet therapy (DAPT) following drug-eluting stent (DES) placement for ≥12 months in acute coronary syndrome or 6 months in stable coronary artery disease. However, with the advent of newer-generation stents, the optimal duration of DAPT to balance bleeding and thrombotic risks has been debated.

OBJECTIVES

We aimed to perform a meta-analysis of randomized controlled trials (RCT) comparing P2Y₁₂ monotherapy in short-duration group (SDG) vs. standard treatment group (STG) course of DAPT in patients undergoing PCI.

METHODS

Electronic databases were searched for RCTs of patients undergoing percutaneous coronary intervention (PCI) with DES placement who received short (≤ 3 months) vs. standard DAPT course (≥12 months) and were followed for ≥12-months. Rates of major adverse cardiovascular events (a composite of cardiovascular mortality, non-fatal myocardial infarction, and non-fatal stroke) were the primary outcome. Study-specific odds ratios (OR) and corresponding 95% confidence intervals were calculated using random-effects model.

RESULTS

A total of 20,706 patients (10,344 in the SDG and 10,362 in the STG) were analysed from four studies. There was no significant difference observed for MACE (OR = 0.95, 95% CI: 0.81-1.08, P = .92, I² = 0%) myocardial infarction or stent thrombosis. However, lower rates of major bleeding were noted in the SDG (1.20 vs. 1.80%; OR: 0.61; 95% CI: 0.37-0.99; P = .04; I² = 71%) albeit with increased heterogeneity.

CONCLUSION

A short duration of DAPT followed by P2Y₁₂ inhibitor monotherapy was comparable to 12 months of DAPT with respect to MACE and thrombotic events, with lower rates of major bleeding events in select group of patients undergoing PCI. More data is needed to assess efficacy in patients with complex lesions and high risk ACS population including those with STEMI presentation.

Effect of P2Y12 inhibitor monotherapy versus dual antiplatelet therapy on cardiovascular events in patients undergoing percutaneous coronary intervention: systematic review and meta-analysis

INTRODUCTION

Clinical data on short mandatory dual antiplatelet therapy (DAPT) followed by P2Y12 inhibitor monotherapy, compared with prolonged DAPT in patients undergoing percutaneous coronary intervention (PCI) are insufficient. We aim to evaluate the effectiveness and safety of P2Y12 inhibitor monotherapy and prolonged DAPT after short mandatory DAPT on cardiovascular events in patients undergoing PCI.

EVIDENCE ACQUISITION

A systematic literature search was performed in seven medical databases from building the database until July 2019. Three studies with randomized controlled trial (RCTs), totaling 21,970 patients, were included in this meta-analysis. The included studies were assessed by the Cochrane risk of bias and analyzed by Review Manager v. 5.3 software.

EVIDENCE SYNTHESIS

Our result of pooled analysis showed that there was noninferior rates of in major adverse cardiac and cerebrovascular events (MACCE), stroke, myocardial infarction and cardiac death between short mandatory DAPT followed by P2Y12 inhibitor monotherapy and prolonged DAPT in patients undergoing PCI. Pooled analysis showed that short mandatory DAPT followed by P2Y12 inhibitor monotherapy could significantly reduce the risk of bleeding BARC type 2-5 (OR=0.47, 95% CI: 0.31-0.70, P=0.002), compared with prolonged DAPT in patients undergoing PCI. However, Pooled analysis showed that short mandatory DAPT followed by P2Y12 inhibitor monotherapy was not associated with BARC type 3-5, compared with prolonged DAPT.

CONCLUSIONS

This meta-analysis demonstrated that short mandatory DAPT followed by P2Y12 inhibitor monotherapy compared with prolonged DAPT resulted in noninferior rates of MACCE, all-cause mortality, cardiac death, stroke, myocardial infarction and stent thrombosis. Furthermore, short mandatory DAPT followed by P2Y12 inhibitor monotherapy could significantly reduce the risk of bleeding BARC type 2-5.

Monotherapy with a P2Y12 inhibitor or aspirin for secondary prevention in patients with established atherosclerosis: a systematic review and meta-analysis

BACKGROUND

Antiplatelet therapy is recommended among patients with established atherosclerosis. We compared monotherapy with a P2Y₁₂ inhibitor versus aspirin for secondary prevention.

METHODS

In this systematic review and meta-analysis, all randomised trials comparing P2Y₁₂ inhibitor with aspirin monotherapy for secondary prevention in patients with cerebrovascular, coronary, or peripheral artery disease were evaluated for inclusion. On Dec 18, 2019, we searched PubMed, Embase, BioMedCentral, Google Scholar, and the Cochrane Central Register of Controlled Trials. Additionally, we reviewed references from identified articles and searched abstracts from 2017 to 2019 presented at relevant scientific meetings. Data about year of publication, inclusion and exclusion criteria, sample size, baseline patients' features including the baseline condition determining study inclusion (ie, cerebrovascular, coronary, or peripheral artery disease), P2Y₁₂ inhibitor type and dosage, aspirin dosage, endpoint definitions, effect estimates, follow-up duration, and percentage of patients lost to follow-up were collected. Odds ratios (ORs) and 95% CIs were used as metric of choice for treatment effects with random-effects models. Co-primary endpoints were myocardial infarction and stroke. Key secondary endpoints were all-cause death and vascular death. Heterogeneity was assessed with the I² index. This study is registered with PROSPERO (CRD42018115037).

FINDINGS

A total of nine randomised trials were identified and included in this study, and 42 108 patients randomly allocated to a P2Y₁₂ inhibitor (n=21 043) or aspirin (n=21 065) were included in our analyses. Patients who received a P2Y₁₂ inhibitor had a borderline reduction for the risk of myocardial infarction compared with those who received aspirin (OR 0·81 [95% CI 0·66-0·99]; I²=10·9%). Risks of stroke (OR 0·93 [0·82-1·06]; I²=34·5%), all-cause death (OR 0·98 [0·89-1·08]; I²=0%), and vascular death (OR 0·97 [0·86-1·09]; I²=0%) did not differ between patients who received a P2Y₁₂ inhibitor and those who received aspirin. Similarly, the risk of major bleeding (OR 0·90 [0·74-1·10]; I²=3·9%) did not differ between patients who received a P2Y₁₂ inhibitor and those who received aspirin. The number needed to treat to prevent one myocardial infarction with P2Y₁₂ inhibitor monotherapy was 244 patients. Findings were consistent regardless of the type of P2Y₁₂ inhibitor used.

INTERPRETATION

Compared with aspirin monotherapy, P2Y₁₂ inhibitor monotherapy is associated with a risk reduction for myocardial infarction and a comparable risk of stroke in the setting of secondary prevention. The benefit of P2Y₁₂ inhibitor monotherapy is of debatable clinical relevance, in view of the high number needed to treat to prevent a myocardial infarction and the absence of any effect on all-cause and vascular mortality.

FUNDING

Italian Ministry of Education.

The efficacy and safety of P2Y12 inhibitor monotherapy in patients after percutaneous coronary intervention

The optimal antiplatelet therapy after percutaneous coronary intervention (PCI) remains to be elucidated. Monotherapy with a P2Y12 inhibitor may be inferior to dual antiplatelet therapy in patients after PCI. PubMed, EMBASE (by Ovidsp), Web of Science, and The Cochrane Library were searched from database inception to 2 October 2019. The composite of cardiovascular outcomes, all-cause mortality, myocardial infarction (MI), stroke, stent thrombosis, and major bleeding were evaluated. Pooled outcomes were presented as relative risk (RR) and 95% confidence intervals (CIs). A total of four trials randomizing 29 089 participants were included. Compared with the dual antiplatelet therapy group (n = 14 559), the P2Y12 inhibitor monotherapy group (n = 14 530) significantly decreased the incidence of bleeding events (2.0% vs 3.1%; RR: 0.60; 95% CI: 0.43-0.84; P = .005). There were no significant differences in all-cause mortality (1.3% vs 1.5%; RR: 0.87; 95% CI, 0.71-1.06; P = .16), myocardial infarction (2.1% vs 1.9%; RR, 1.06; 95% CI, 0.90-1.25; P = .46), stroke (0.6% vs 0.5%; RR, 1.18; 95% CI, 0.67-2.07; P = .57), or stent thrombosis (0.5% vs 0.4%; RR, 1.14; 95% CI, 0.81-1.61; P = .44) between the two groups. P2Y12 inhibitor monotherapy did not show any significant difference in the adverse cardiac and cerebrovascular events, but markedly decreased the risk of bleeding among patients after PCI vs dual antiplatelet therapy. However, it still needs to be further confirmed due to limited data.

Differential Effects of Ticagrelor With or Without Aspirin on Platelet Reactivity and Coagulation Activation: A Randomized Trial in Healthy Volunteers

Dual antiplatelet therapy (DAPT) is standard in acute coronary heart disease but confers a bleeding risk. To compare the effects of ticagrelor‐monotherapy with ticagrelor‐based DAPT on hemostatic system activation, we conducted a randomized controlled trial in 44 volunteers using a loading‐dose regimen and measured platelet‐aggregometry triggered by adenosine diphosphate (multiple electrode aggregometry (MEA)‐ADP) and arachidonic acid (MEA‐AA), the vasodilator‐stimulated phosphoprotein (VASP), prothrombin fragment 1.2 (f1.2), and d‐Dimer. Ticagrelor‐based DAPT and ticagrelor‐monotherapy significantly decreased MEA‐ADP (Δmean: −51.4 (−56.9; −45.8) and −46.2 (−51.7; −40.7)) and VASP (Δmean: −70.3 (−76.2; −64.4) and −69.6 (−75.5; −63.7)) at 2 hours and over 24 hours. MEA‐AA was reduced significantly by both treatments (Δmean: −72.9 (−80.6; −65.3) and −25.7 (−33.3; −18.0)) at 2 hours, and stronger by ticagrelor‐based DAPT over 24 hours. Both treatments decreased f1.2 (geometric mean ratio (GMR): 0.92 (0.84; 1.01) and 0.88 (0.80; 0.96)) and d‐Dimer (GMR: 0.89 (0.86; 0.92) and 0.91 (0.88; 0.94)) at 2 hours and d‐Dimer over 24 hours. Ticagrelor‐monotherapy and ticagrelor‐based DAPT comparably affect hemostatic system activation.

Pharmacodynamic Effects of Vorapaxar in Patients With and Without Diabetes Mellitus: Results of the OPTIMUS-5 Study

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Vorapaxar reduces thrombotic cardiovascular events in patients with atherosclerotic disease, with enhanced effects in those with DM.

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Adjunctive vorapaxar therapy reduces platelet-mediated thrombogenicity without affecting clot kinetics in both patients with and those without DM having prior MI/PAD on dual antiplatelet therapy with aspirin and clopidogrel.

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The pharmacodynamic effects of vorapaxar occur via selective blockade of the PAR-1 on the platelet membrane without apparent interplay with other platelet signaling pathways.

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Aspirin withdrawal, which leaves patients on a background of clopidogrel and vorapaxar, increases markers specific to COX-1–mediated blockade, leading to an increase in platelet-mediated global thrombogenicity, particularly among patients with DM.

Vorapaxar reduces thrombotic cardiovascular events at the expense of increased bleeding. However, the differential pharmacodynamic (PD) effects of vorapaxar according to diabetes mellitus (DM) status are unknown. Moreover, although withdrawal of aspirin has emerged as a bleeding reduction strategy, the PD effects of stopping aspirin in patients treated with vorapaxar also are unknown. In this prospective PD investigation, vorapaxar was associated with reduced platelet-mediated thrombogenicity without affecting clot kinetics irrespective of DM status. However, platelet-mediated thrombogenicity increased after aspirin withdrawal, particularly among patients with DM. (Optimizing anti-Platelet Therapy In diabetes MellitUS-5 Study [OPTIMUS-5]; NCT02548650)

Effect of P2Y12 Inhibitor Monotherapy vs Dual Antiplatelet Therapy on Cardiovascular Events in Patients Undergoing Percutaneous Coronary Intervention: The SMART-CHOICE Randomized Clinical Trial

IMPORTANCE

Data on P2Y12 inhibitor monotherapy after short-duration dual antiplatelet therapy (DAPT) in patients undergoing percutaneous coronary intervention are limited.

OBJECTIVE

To determine whether P2Y12 inhibitor monotherapy after 3 months of DAPT is noninferior to 12 months of DAPT in patients undergoing PCI.

DESIGN, SETTING, AND PARTICIPANTS

The SMART-CHOICE trial was an open-label, noninferiority, randomized study that was conducted in 33 hospitals in Korea and included 2993 patients undergoing PCI with drug-eluting stents. Enrollment began March 18, 2014, and follow-up was completed July 19, 2018.

INTERVENTIONS

Patients were randomly assigned to receive aspirin plus a P2Y12 inhibitor for 3 months and thereafter P2Y12 inhibitor alone (n = 1495) or DAPT for 12 months (n = 1498).

MAIN OUTCOMES AND MEASURES

The primary end point was major adverse cardiac and cerebrovascular events (a composite of all-cause death, myocardial infarction, or stroke) at 12 months after the index procedure. Secondary end points included the components of the primary end point and bleeding defined as Bleeding Academic Research Consortium type 2 to 5. The noninferiority margin was 1.8%.

RESULTS

Among 2993 patients who were randomized (mean age, 64 years; 795 women [26.6%]), 2912 (97.3%) completed the trial. Adherence to the study protocol was 79.3% of the P2Y12 inhibitor monotherapy group and 95.2% of the DAPT group. At 12 months, major adverse cardiac and cerebrovascular events occurred in 42 patients in the P2Y12 inhibitor monotherapy group and in 36 patients in the DAPT group (2.9% vs 2.5%; difference, 0.4% [1-sided 95% CI, -∞% to 1.3%]; P = .007 for noninferiority). There were no significant differences in all-cause death (21 [1.4%] vs 18 [1.2%]; hazard ratio [HR], 1.18; 95% CI, 0.63-2.21; P = .61), myocardial infarction (11 [0.8%] vs 17 [1.2%]; HR, 0.66; 95% CI, 0.31-1.40; P = .28), or stroke (11 [0.8%] vs 5 [0.3%]; HR, 2.23; 95% CI, 0.78-6.43; P = .14) between the 2 groups. The rate of bleeding was significantly lower in the P2Y12 inhibitor monotherapy group than in the DAPT group (2.0% vs 3.4%; HR, 0.58; 95% CI, 0.36-0.92; P = .02).

CONCLUSIONS AND RELEVANCE

Among patients undergoing percutaneous coronary intervention, P2Y12 inhibitor monotherapy after 3 months of DAPT compared with prolonged DAPT resulted in noninferior rates of major adverse cardiac and cerebrovascular events. Because of limitations in the study population and adherence, further research is needed in other populations.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02079194.

Randomized evaluation of ticagrelor monotherapy after 3-month dual-antiplatelet therapy in patients with acute coronary syndrome treated with new-generation sirolimus-eluting stents: TICO trial rationale and design

BACKGROUND

Ticagrelor monotherapy after short-term dual-antiplatelet therapy (DAPT) may optimize ischemic and bleeding risks, particularly for acute coronary syndrome (ACS) patients, because its strategy is less potent than ticagrelor-based DAPT but more potent than aspirin or clopidogrel monotherapy.

METHODS

The TICO randomized open-label trial will evaluate whether ticagrelor monotherapy following 3-month DAPT is superior to 12-month ticagrelor-based DAPT in terms of net adverse clinical events (NACE) including efficacy and safety in ACS patients treated with ultrathin bioresorbable polymer sirolimus-eluting stents (BP-SES). Patients undergoing BP-SES implantation for ACS treatment will be randomized in a 1:1 fashion to the (1) ticagrelor monotherapy group after 3-month DAPT; or the (2) 12-month DAPT group. The primary endpoint is NACE within 12 months of percutaneous coronary intervention, which includes major adverse cardiac and cerebrovascular events (MACCE) plus major bleeding as defined by Thrombolysis in Myocardial Infarction. MACCE includes the composite of all-cause death, myocardial infarction, stent thrombosis, stroke, and target vessel revascularization. Secondary endpoints included each component of the primary endpoint.

CONCLUSIONS

The TICO trial is an ongoing trial evaluating the efficacy and safety of ticagrelor monotherapy following 3-month DAPT exclusively in ACS patients treated with uniform BP-SES. It may provide novel insights regarding the need for adjusted use of DAPT for rebalancing risk-benefit in current practice and changing from the conventional concept of aspirin maintenance to a ticagrelor-based regimen in the management of ACS.

Effects of clopidogrel with or without aspirin on the generation of extracellular vesicles in the microcirculation and in venous blood: A randomized placebo controlled trial

BACKGROUND

Dual-antiplatelet therapy (DAPT) is a standard strategy in acute coronary heart disease; however, it confers a considerable bleeding risk. Single-antiplatelet therapy (SAPT) inhibits haemostatic system activation ex vivo to a similar extent as DAPT. Extracellular vesicles (EV) are procoagulant and contribute to haemostatic system activation. We aimed to investigate the effect of DAPT compared with SAPT on EV.

METHODS

In a randomized, double-blind, placebo-controlled trial, 44 healthy volunteers received DAPT (clopidogrel + aspirin) or SAPT (clopidogrel + placebo) for 7 days. Blood was obtained from a standardized microvascular injury and through venipuncture at baseline (BL) and at 2 h, 24 h, and 8 days after treatment initiation. The number, origin, and surface expression of EV were assessed using flow cytometry. Data are given as median (quartiles). Non-parametric tests were used to evaluate the short-term (BL vs 2 h) and long-term differences (2 h to 8 days), as well as the differences between treatment groups.

RESULTS

There was no difference either in the short-term effects on the number (×10³ mL^-1) of EV in microvascular blood between DAPT [BL: 1433 (653; 3184) vs 2 h: 862 (545; 2026), p = 0.39] and SAPT [(BL: 614 (552; 1402) vs 2 h: 1079 (781; 1538), p = 0.75)] or in the long-term effects. DAPT and SAPT did not exhibit differential short-term effects on the number and proportion (36% and 27% vs 55% and 36%) of platelet-derived EV. DAPT and SAPT resulted in a significant short-term increase in phosphatidylserine expression in microvascular blood. The effects of DAPT and SAPT on EV in venous blood were similar to those in microvascular blood.

CONCLUSION

DAPT and SAPT have comparable effects on the amount, origin, and surface characteristics of EV.

Rationale and design of the comparison between a P2Y12 inhibitor monotherapy versus dual antiplatelet therapy in patients undergoing implantation of coronary drug-eluting stents (SMART-CHOICE): A prospective multicenter randomized trial

BACKGROUND AND RATIONALE

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor reduces thrombotic events in patients undergoing percutaneous coronary intervention (PCI), but these benefits come at the expense of increased risk of bleeding when compared with aspirin monotherapy. It is unclear whether P2Y12 inhibitor monotherapy might maintain anti-ischemic efficacy while reducing the bleeding risk compared with DAPT after implantation of the current generation of drug-eluting stents (DES).

STUDY DESIGN

The SMART-CHOICE trial is a prospective, open-label, multi-center, and randomized study designed to test the non-inferiority of P2Y12 inhibitor monotherapy compared with aspirin plus a P2Y12 inhibitor after mandatory 3-month DAPT in patients undergoing PCI with current-generation DES. A total of 3000 patients will be randomized to 1 of the 2 antiplatelet treatment strategy groups. Randomization will be stratified by stent type (cobalt-chromium everolimus-eluting stents, platinum-chromium everolimus-eluting stents, and sirolimus-eluting stents with bioresorbable polymer), P2Y12 inhibitors (clopidogrel, prasugrel, and ticagrelor), clinical presentation (acute coronary syndrome and stable ischemic heart disease), and investigational centers. The primary end point is a composite of all-cause death, myocardial infarction, and cerebrovascular events at 12 months after the index procedure. The key secondary end points are definite/probable stent thrombosis defined by the Academic Research Consortium, and bleeding defined by Bleeding Academic Research Consortium type 2-5.

CONCLUSIONS

The SMART-CHOICE trial aims to examine the non-inferiority of monotherapy with one of any available oral P2Y12 inhibitors versus conventional DAPT of an identical P2Y12 inhibitor plus aspirin in a broad spectrum of patients receiving representative current-generation DES.