Six months versus 12 months dual antiplatelet therapy after drug-eluting stent implantation in ST-elevation myocardial infarction (DAPT-STEMI): randomised, multicentre, non-inferiority trial

OBJECTIVE

To show that limiting dual antiplatelet therapy (DAPT) to six months in patients with event-free ST-elevation myocardial infarction (STEMI) results in a non-inferior clinical outcome versus DAPT for 12 months.

DESIGN

Prospective, randomised, multicentre, non-inferiority trial.

SETTING

Patients with STEMI treated with primary percutaneous coronary intervention (PCI) and second generation zotarolimus-eluting stent.

PARTICIPANTS

Patients with STEMI aged 18 to 85 that underwent a primary PCI with the implantation of second generation drug-eluting stents were enrolled in the trial. Patients that were event-free at six months after primary PCI were randomised at this time point.

INTERVENTIONS

Patients that were taking DAPT and were event-free at six months were randomised 1:1 to single antiplatelet therapy (SAPT) (ie, aspirin only) or to DAPT for an additional six months. All patients that were randomised were then followed for another 18 months (ie, 24 months after the primary PCI).

MAIN OUTCOME MEASURES

The primary endpoint was a composite of all cause mortality, any myocardial infarction, any revascularisation, stroke, and thrombolysis in myocardial infarction major bleeding at 18 months after randomisation.

RESULTS

A total of 1100 patients were enrolled in the trial between 19 December 2011 and 30 June 2015. 870 were randomised: 432 to SAPT versus 438 to DAPT. The primary endpoint occurred in 4.8% of patients receiving SAPT versus 6.6% of patients receiving DAPT (hazard ratio 0.73, 95% confidence interval 0.41 to 1.27, P=0.26). Non-inferiority was met (P=0.004 for non-inferiority), as the upper 95% confidence interval of 1.27 was smaller than the prespecified non-inferiority margin of 1.66.

CONCLUSIONS

DAPT to six months was non-inferior to DAPT for 12 months in patients with event-free STEMI at six months after primary PCI with second generation drug-eluting stents.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01459627.

The optimal duration of dual antiplatelet therapy after coronary stent implantation: to go too far is as bad as to fall short

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is key for secondary prevention of recurrent coronary ischemic events and stent thrombosis. For this purpose, DAPT showed superior efficacy compared to aspirin alone, but it is also associated with an increased risk of major, and potentially fatal, bleeding. Hence, while secondary prevention with aspirin monotherapy is generally maintained for an indefinite period, the duration of DAPT after the index event is still debated. Multiple trials have challenged the guideline recommended standard of care of 12 months of DAPT duration. These studies tested on one side a treatment reduction to 6 or 3 months, and on the other side an extension of treatment beyond 12 months in order to define the optimal DAPT duration maximizing the anti-ischemic protection and minimizing bleeding. In this document we sought to summarize the existing evidence from more than 18 randomized controlled trials in the field, and discuss the benefit and risks of prolonging/shortening DAPT duration. In addition, a specific focus on treatment individualization will outline the current, evidence-based, decision-making process for optimal DAPT duration selection after coronary stenting.

Oral antiplatelets in primary and secondary prevention of myocardial infarction: a review

There are a number of guidelines and articles available for the use of oral antiplatelets for primary and secondary prevention of myocardial infarction (MI). Antiplatelet medications inhibit platelet activation, aggregation, and other pathways eventually inhibiting clot formation. Aspirin and clopidogrel have been the mainstay in the management of acute coronary syndrome for about a decade. We have discussed the role of aspirin, clopidogrel, ticagrelor, and prasugrel which are the most commonly used oral antiplatelet medications in the current era. We have also considered the role of newer thrombin inhibitor vorapaxar, and dual antiplatelet therapy. In this review paper, we have summarized the continuing controversy about the use of oral antiplatelet therapy and their role in primary as well as secondary prevention of MI by describing results from major clinical trials. The safety and the efficacy of the above medications have been reviewed and described in this paper.

Short-versus long-term dual antiplatelet therapy after second-generation drug-eluting stent implantation: a systematic review and meta-analysis of randomized controlled trials

Background

The optimal dual antiplatelet therapy (DAPT) duration after second-generation drug-eluting stent (DES) implantation remains unclear. We aim to evaluate the efficacy and safety of short-term (≤6 months) and long-term (≥12 months) DAPT after second-generation DES implantation.

Methods

Randomized controlled trials (RCTs) were searched in PubMed, the Cochrane Library, the Embase and ClinicalTrials.gov in the English language. The endpoints included all-cause mortality, cardiac death, non-cardiac death, myocardial infarction (MI), stent thrombosis (ST), stroke, all bleeding, and major bleeding. The effect estimate was expressed by using the hazard ratio (HR) with 95% CI and random effect models.

Results

Seven RCTs with 13,571 patients were included in this study. In terms of survival endpoints, there was no significant difference in all-cause mortality (HR: 0.91; 95% CI: 0.71–1.17), cardiac death (HR: 0.93; 95% CI: 0.67–1.29), and non-cardiac death (HR: 0.89; 95% CI: 0.62–1.28) in the 2 groups. Moreover, there was no significant difference in ischemic outcomes, including MI (HR: 1.15; 95% CI: 0.91–1.45), ST (HR: 1.11; 95% CI: 0.75–1.66), and stroke (HR: 0.85; 95% CI: 0.53–1.35) in the 2 groups. In terms of bleeding endpoints, there was no significant difference in all bleeding (HR: 0.81; 95% CI: 0.64–1.04) and major bleeding (HR: 0.82; 95% CI: 0.49–1.36) in the 2 groups. The subgroup analysis showed that the proportion of patients with acute coronary syndrome was not associated with the benefit of long-term versus short-term DAPT.

Conclusion

Short-term DAPT is not inferior to long-term DAPT in patients implanted with second-generation DES.

State of the art: duration of dual antiplatelet therapy after percutaneous coronary intervention and coronary stent implantation - past, present and future perspectives

Evidence from studies published more than 10 years ago suggested that patients receiving first-generation drug-eluting stents (DES) needed dual antiplatelet therapy (DAPT) for at least 12 months. Current evidence from randomised controlled trials (RCT) reported within the past five years suggests that patients with stable ischaemic heart disease who receive newer-generation DES need DAPT for a minimum of three to six months. Patients who undergo stenting for an acute coronary syndrome benefit from DAPT for at least 12 months, but a Bayesian network meta-analysis confirms that extending DAPT beyond 12 months confers a trade-off between reduced ischaemic events and increased bleeding. However, the network meta-analysis finds no credible increase in all-cause mortality if DAPT is lengthened from three to six months to 12 months (posterior median odds ratio [OR] 0.98; 95% Bayesian credible interval [BCI]: 0.73-1.43), from 12 months to 18-48 months (OR 0.87; 95% BCI: 0.64-1.17), or from three to six months to 18-48 months (OR 0.86; 95% BCI: 0.63-1.21). Future investigation should focus on identifying scoring systems that have excellent discrimination and calibration. Although predictive models should be incorporated into systems of care, most decisions about DAPT duration will be based on clinical judgement and patient preference.

Risk of Early Adverse Events After Clopidogrel Discontinuation in Patients Undergoing Short-Term Dual Antiplatelet Therapy: An Individual Participant Data Analysis

OBJECTIVES

The study sought to evaluate the presence of a clinically relevant rebound phenomenon after dual antiplatelet therapy (DAPT) discontinuation in randomized trials.

BACKGROUND

It is currently unknown whether clopidogrel discontinuation after short-term DAPT is associated with an early hazard of ischemic events.

METHODS

The authors performed an individual participant data analysis and aggregate meta-analysis. The primary outcome was major adverse cardiac and cerebrovascular events (MACCE), defined as the composite of cardiac death, myocardial infarction (MI), or stroke.

RESULTS

The study included 11,473 PCI patients with individual participant data from 6 randomized trials comparing short-term DAPT (3 or 6 months) versus long-term DAPT (12 months or more). During the first 90 days following clopidogrel discontinuation, there was no significant increase in the risk of MACCE between patients randomized to short-term DAPT compared with long-term DAPT (hazard ratio [HR]: 1.18; 95% confidence interval [CI]: 0.71 to 1.98; p = 0.52; absolute risk difference 0.10%; 95% CI: -0.16% to 0.36%). The risk of MI or stent thrombosis was similar among patients randomized to short-term DAPT versus long-term DAPT (HR: 0.93; 95% CI: 0.46 to 1.90; p = 0.85). In the aggregate data meta-analysis of 11 trials including 38,919 patients, a higher risk of early MACCE was observed after long-term (≥12 months) DAPT duration (HR: 2.28; 95% CI: 1.69 to 3.09; p < 0.001) but not short-term (<12 months) DAPT duration (HR: 1.08; 95% CI: 0.67 to 1.74; p for interaction = 0.036).

CONCLUSIONS

Among patients undergoing PCI with predominantly new-generation DES, discontinuation of clopidogrel after 3 or 6 months DAPT duration was not associated with an early increase in adverse clinical events. An early increase in MACCE was observed after long-term (≥12 months) DAPT exposure.

Are Shorter Durations of Dual Antiplatelet Therapy Acceptable Following Percutaneous Coronary Intervention?

Much debate has centered on whether or not the standard 12-month duration of dual antiplatelet therapy (DAPT) is still necessary postpercutaneous coronary intervention, given recent improvements in stent technology. The benefits of shorter (3-6 months) durations of DAPT include a potential lower risk for bleeding and less patient drug cost and pill burden. Although randomized clinical trials have shown noninferiority for shorter versus longer DAPT regimens in many regards, some endpoints (e.g., myocardial infarction) may still occur less frequently with longer DAPT regimens, particularly in higher risk populations (e.g., acute coronary syndromes). Bleeding risk is either comparable or less with shorter versus longer DAPT regimens. Given the lack of unequivocal data regarding the equality of shorter versus longer DAPT regimens in all patients, there is a growing consensus that an individualized approach is advisable for determining DAPT duration postpercutaneous coronary intervention. Clinical decision aids and updated clinical practice guidelines are available that consider risk:benefit ratios and clinical trial data to assist the clinician in developing a personalized DAPT regimen.

Bayesian Analysis: A Practical Approach to Interpret Clinical Trials and Create Clinical Practice Guidelines

Bayesian analysis is firmly grounded in the science of probability and has been increasingly supplementing or replacing traditional approaches based on P values. In this review, we present gradually more complex examples, along with programming code and data sets, to show how Bayesian analysis takes evidence from randomized clinical trials to update what is already known about specific treatments in cardiovascular medicine. In the example of revascularization choices for diabetic patients who have multivessel coronary artery disease, we combine the results of the FREEDOM trial (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease) with prior probability distributions to show how strongly we should believe in the new Class I recommendation ("should be done") for a preference of bypass surgery over percutaneous coronary intervention. In the debate about the duration of dual antiplatelet therapy after drug-eluting stent implantation, we avoid a common pitfall in traditional meta-analysis and create a network of randomized clinical trials to compare outcomes after specific treatment durations. Although we find no credible increase in mortality, we affirm the tradeoff between increased bleeding and reduced myocardial infarctions with prolonged dual antiplatelet therapy, findings that support the new Class IIb recommendation ("may be considered") to extend dual antiplatelet therapy after drug-eluting stent implantation. In the decision between culprit artery-only and multivessel percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction, we use hierarchical meta-analysis to analyze evidence from observational studies and randomized clinical trials and find that the probability of all-cause mortality at longest follow-up is similar after both strategies, a finding that challenges the older ban against noninfarct-artery intervention during primary percutaneous coronary intervention. These examples illustrate how Bayesian analysis integrates new trial information with existing knowledge to reduce uncertainty and change attitudes about treatments in cardiovascular medicine.

Optimal duration of dual antiplatelet therapy for coronary artery disease

The optimal duration of dual antiplatelet therapy (DAPT) for stable coronary artery disease and acute coronary syndrome is a complex decision. We review current literature on standard duration DAPT versus short duration DAPT (6 months or shorter) or extended duration DAPT (>12 months) after percutaneous coronary intervention with drug-eluting stent placement, and prolonged treatment after 12 months in acute coronary syndrome. Current guideline recommendations are summarised, including the use of risk scores for ischaemic and bleeding risk assessment. Because of the limitations of current risk scores, we propose multiple patient-related and procedure-related factors for the ischaemic and bleeding risk assessment aiding in personalised DAPT duration.

Dual Antiplatelet Therapy for 6 Versus 18 Months After Biodegradable Polymer Drug-Eluting Stent Implantation

OBJECTIVES

The NIPPON (Nobori Dual Antiplatelet Therapy as Appropriate Duration) study was a multicenter randomized investigation of the noninferiority of short-term versus long-term dual antiplatelet therapy (DAPT) in patients with implantation of the Nobori drug-eluting stent (DES) (Terumo, Tokyo, Japan), which has a biodegradable abluminal coating.

BACKGROUND

The optimum duration of DAPT for patients with a biodegradable polymer-coated DES is unclear.

METHODS

The subjects were 3,773 patients with stable or acute coronary syndromes undergoing Nobori stent implantation. They were randomized 1:1 to receive DAPT for 6 or 18 months. The primary endpoint was net adverse clinical and cerebrovascular events (NACCE) (all-cause mortality, myocardial infarction, stroke, and major bleeding) from 6 to 18 months after stenting. Intention-to-treat analysis was performed in 3,307 patients who were followed for at least 6 months.

RESULTS

NACCE occurred in 34 patients (2.1%) receiving short-term DAPT and 24 patients (1.5%) receiving long-term DAPT (difference 0.6%, 95% confidence interval [CI]: 1.5 to 0.3). Because the lower limit of the 95% CI was inside the specified margin of -2%, noninferiority of short-term DAPT was confirmed. Mortality was 1.0% with short-term DAPT versus 0.4% with long-term DAPT, whereas myocardial infarction was 0.2% versus 0.1%, and major bleeding was 0.7% versus 0.7%, respectively. The estimated probability of NACCE was lower in the long-term DAPT group (hazard ratio: 1.44, 95% CI: 0.86 to 2.43).

CONCLUSIONS

Six months of DAPT was not inferior to 18 months of DAPT following implantation of a DES with a biodegradable abluminal coating. However, this result needs to be interpreted with caution given the open-label design and wide noninferiority margin of the present study. (Nobori Dual Antiplatelet Therapy as Appropriate Duration [NIPPON]; NCT01514227).

6- Versus 24-Month Dual Antiplatelet Therapy After Implantation of Drug-Eluting Stents in Patients Nonresistant to Aspirin: Final Results of the ITALIC Trial (Is There a Life for DES After Discontinuation of Clopidogrel)

OBJECTIVES

The aim of this study was to test the hypothesis that 6-month dual antiplatelet therapy (DAPT) is noninferior to 24-month DAPT in aspirin-sensitive patients.

BACKGROUND

The ITALIC (Is There a Life for DES After Discontinuation of Clopidogrel) trial showed that rates of bleeding and thrombotic events at 1 year were much the same with 6 versus 12 months of DAPT after percutaneous coronary intervention with second-generation drug-eluting stents. In this report, 2-year follow-up is presented.

METHODS

In a multicenter randomized study, patients with confirmed nonresistance to aspirin undergoing drug-eluting stent implantation were allocated to 6 or 24 months of DAPT. The primary endpoint was a composite of death, myocardial infarction, urgent target vessel revascularization, stroke, and major bleeding at 12 months post-percutaneous coronary intervention. The secondary endpoints comprised the same composite endpoint at 24 months and each individual component.

RESULTS

Overall, 2,031 patients from 70 centers were screened; 926 were randomized to 6-month and 924 to 24-month DAPT. Noninferiority was demonstrated for 6- versus 12-month DAPT, with an absolute risk difference of 0.11% (95% confidence interval: -1.04% to 1.26%; p = 0.0002). At 2 years, the composite endpoint was unchanged, at 3.5% for 6 months and 3.7% for 24 months (p = 0.79), and rates of myocardial infarction (1.3% vs. 1.0%; p = 0.51), stroke (0.6% vs. 0.8%; p = 0.77), and target vessel revascularization (1.0% vs. 0.3%; p = 0.09) were likewise similar. There was a trend toward higher mortality with longer DAPT (2.2% vs. 1.2%; p = 0.11). Four patients (0.4%) in the 24-month group and none in the 6-month group had major bleeding.

CONCLUSIONS

Two-year outcomes in the ITALIC trial confirmed the 1-year results and showed that patients receiving 6-month DAPT after percutaneous coronary intervention with second-generation drug-eluting stent have similar outcomes to those receiving 24-month DAPT.

Antiplatelet Therapy in Coronary Artery Disease: A Daunting Dilemma

Percutaneous coronary intervention (PCI) with stenting for the treatment of acute coronary syndrome (ACS) is the contemporary standard of care. Such treatment is followed by dual antiplatelet therapy (DAPT) comprising of aspirin and a P2Y12 inhibitor. The efficacy of this therapy has been well established but the optimal duration of DAPT remains elusive, and has thus far attracted a prodigious deal of scientific attention. The decision regarding DAPT duration can be clinically challenging in the modern era with the evolution of newer stents, more potent antiplatelet agents, and novel anticoagulant drugs in addition to an older patient population with multiple comorbidities. Major societal guidelines have emphasized comprehensive assessment of ischemic and bleeding risk, in turn recommending individualization of DAPT duration, thus encouraging "shared decision making". The following review is aimed at critically evaluating the available evidence to help make these crucial clinical decisions regarding duration of DAPT and triple therapy.

Short versus long duration of dual antiplatelet therapy following drug-eluting stents: a meta-analysis of randomised trials

Background

Dual antiplatelet therapy (DAPT) remains the cornerstone therapy in the prevention of ischaemic events following drug-eluting stent (DES) implantation. Mandatory duration of DAPT after DES however, is a matter of debate. We aimed to evaluate safety and efficacy of short-term (up to 6 months) versus long-term (12 months) DAPT after DES implantation.

Methods

We searched PubMed, EMBASE, Cochrane databases, and international meetings for randomised clinical trials (RCTs) comparing short with long DAPT. We performed a systematic review and meta-analysis of major trials with primary outcomes: all-cause death, myocardial infarction, definite or probable stent thrombosis, stroke, and major bleeding event.

Results

Nine RCTs with a total number of 19,099 patients were pooled in the present meta-analysis. When compared with long DAPT, short DAPT was associated with a significant reduction in major bleeding events (0.62% vs. 1.10%, risk ratio (RR) 0.58, 95% confidence interval (CI) 0.39 to 0.86, p < 0.007, I² = 21%), whereas all-cause death (1.65% vs. 1.84%, RR 0.90, 95% CI 0.73 to 1.11, p = 0.34, I2 = 0%), myocardial infarction (1.91% vs. 1.68%, RR 1.14, 95% CI 0.92 to 1.40, p = 0.23, I2 = 0%), definite or probable stent thrombosis (0.62% vs. 0.47%, RR 1.25, 95% CI 0.84 to 1.86, p = 0.27, I2 = 0%), and stroke (0.60% vs. 0.67%, RR 0.91, 95% CI 0.63 to 1.31, p = 0.61, I2 = 0%) were similar.

Conclusions

Short DAPT following DES implantation results in a significant reduction of major bleeding events with no apparent increase in all-cause death, myocardial infarction, stent thrombosis, or stroke. Future dedicated trials should investigate the optimal strategies for patient-tailored DAPT in various subgroups.

Electronic supplementary material

The online version of this article (10.1007/s12471-018-1104-6) contains supplementary material, which is available to authorized users.

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.

Vascular response to biolimus A-9 eluting stent in patients with shorter and prolonged dual antiplatelet therapy: optical coherence tomography sub-study of the NIPPON trial

Dual antiplatelet therapy (DAPT) with thienopyridine and aspirin is the standard care for the prevention of stent thrombosis. However, the optimal duration and effect of the duration of DAPT on intra-stent thrombus (IS-Th) formation are unknown. The NIPPON study (Nobori Dual Antiplatelet Therapy as Appropriate Duration) was an open label, randomized multicenter, assessor-blinded, trial designed to demonstrate the non-inferiority of shorter (6-month) DAPT to prolonged (18-month) DAPT, after biolimus A9 eluting stent implantation in 3773 patients at 130 sites in Japan. Among them, 101 patients were randomly allocated for an optical coherence tomography (OCT) sub-study to assess the difference of local IS-Th formation between the two groups. In addition to standard OCT parameters, the number of IS-Th formed was counted in each target stent at 8 months. Baseline patient characteristics were not different between the 6- and 18-month groups. IS-Th was detected in 9.8% of the cases and the presence of IS-Th was not significantly different between the two groups (10.9% in 6-month vs. 9.1% in 12-month, P = 0.76). Furthermore, the number of IS-Th formed was not significantly different between the two groups. This OCT sub-study was in line with the main NIPPON study which demonstrated the non-inferiority of 6-month DAPT to 18-month DAPT. Shorter DAPT duration did not promote progressive IS-Th formation at the mid-term time point.

Dual antiplatelet therapy after coronary drug-eluting stent implantation in China: A large single center study

OBJECTIVE

To investigate the actual dual antiplatelet therapy (DAPT) duration after drug-eluting stent (DES) treatment in China.

BACKGROUND

Currently, less is known about actual DAPT duration after drug-eluting stent (DES) treatment in China. Here, we performed a study in the largest cardiovascular center in China to investigate DAPT duration and identify associated factors after DES implantation.

METHODS

A total of 9,919 consecutive patients with DES implantation from January 2013 to December 2013 were enrolled. DAPT cessation was observed, and factors associated with different DAPT durations were analyzed.

RESULTS

The median follow-up time was 882 days. The proportion of patients with DAPT coverage at 1-year of follow-up was 97.3%, and it decreased to 30.1% for 2 years. The distribution of DAPT duration was not significantly different among patients with acute myocardial infarction (AMI) versus non-AMI (P = 0.41) and with new-generation DES versus first-generation DES (P = 0.54). The multivariable analysis indicated some independent predictors prolonging DAPT duration, including target vessel revascularization (OR 2.50, 95% CI 2.04-3.06, P < 0.001), stent numbers (OR 1.10, 95% CI 1.05-1.15, P < 0.001), and previous coronary artery bypass grafting (OR 0.76, 95% CI 0.61-0.96, P = 0.02). Other clinical factors, such as the increased risk of bleeding and high ischemic risk, were not associated with DAPT duration.

CONCLUSIONS

The 1-year DAPT after DES was applied to 97.3% of Chinese patients in the studied clinical center. However, the DAPT duration after 1 year was not adjusted according to the patients' bleeding situation and ischemic risks.

Management of antiplatelet therapy in patients undergoing elective invasive procedures. Proposals from the French Working Group on perioperative haemostasis (GIHP) and the French Study Group on thrombosis and haemostasis (GFHT). In collaboration with the French Society for Anaesthesia and Intensive Care Medicine (SFAR)

The French Working Group on Perioperative Haemostasis (GIHP) and the French Study Group on Haemostasis and Thrombosis (GFHT) in collaboration with the French Society for Anaesthesia and Intensive Care Medicine (SFAR) drafted up-to-date proposals for the management of antiplatelet therapy in patients undergoing elective invasive procedures. The proposals were discussed and validated by a vote; all proposals but one could be assigned with a high strength. The management of antiplatelet therapy is based on their indication and the procedure. The risk of bleeding related to the procedure can be divided into high, moderate and low categories depending on the possibility of performing the procedure in patients receiving antiplatelet agents (none, monotherapy and dual antiplatelet therapy respectively). If discontinuation of antiplatelet therapy is indicated before the procedure, a last intake of aspirin, clopidogrel, ticagrelor and prasugrel 3, 5, 5 and 7 days before surgery respectively is proposed. The thrombotic risk associated with discontinuation should be assessed according to each specific indication of antiplatelet therapy and is higher for patients receiving dual therapy for coronary artery disease (with further refinements based on a few well-accepted items) than for those receiving monotherapy for cardiovascular prevention, for secondary stroke prevention or for lower extremity arterial disease. These proposals also address the issue of the potential role of platelet functional tests and consider management of antiplatelet therapy for regional anaesthesia, including central neuraxial anaesthesia and peripheral nerve blocks, and for coronary artery surgery.

Duration of Dual Antiplatelet Therapy After Percutaneous Coronary Intervention: Is Less More?

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) using the latest-generation drug-eluting stents remains a matter of debate. Evidence suggests short regimens of DAPT are favorable for patients with a low ischemic risk, while those at a high risk of ischemia may benefit from taking DAPT for a long duration. An individually assessed risk profile is pivotal in guiding DAPT duration. Risk scores may aid individual patient DAPT decisions, but the value they add to clinical outcomes still needs to be established in a prospective randomized trial. This review aims to provide an overview on DAPT, evaluate the available evidence on DAPT duration with a description of common pitfalls of trial interpretation, and assess available tools for individual risk assessment in patients scheduled for PCI with the latest-generation DES.

The Evolving Concept of Dual Antiplatelet Therapy after Percutaneous Coronary Intervention: Focus on Unique Feature of East Asian and "Asian Paradox"

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is essential after percutaneous coronary intervention (PCI), while many studies have focused on determining the optimal degree of platelet inhibition and optimal DAPT duration to minimize complications after PCI. Current guidelines developed by the American College of Cardiology/American Heart Association and the European Society of Cardiology summarize previous studies and provide recommendations. However, these guidelines are mainly based on Western patients, and their characteristics might differ from those of East Asian patients. Previous data suggested that East Asian patients have unique features with regard to the response to antiplatelet agents. On comparing Western and East Asian patients, it was found that East Asian patients have a lower rate of ischemic events and higher rate of bleeding events after PCI, despite a higher on-treatment platelet reactivity, which is referred to as the “East Asian paradox.” As the main purpose of DAPT is to minimize ischemic and bleeding complications after PCI, these differences should be clarified before adopting the guidelines for East Asian patients. Therefore, in this article, we will review various issues regarding DAPT in East Asian patients, with a focus on the unique characteristics of East Asian patients, previous studies regarding antiplatelet agents in East Asian patients, and a guideline from an East Asian perspective.

Duration of Dual Antiplatelet Therapy Following Drug-Eluting Stent Implantation in Diabetic and Non-Diabetic Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Diabetic patients account for an increasing number of patients undergoing percutaneous coronary intervention (PCI). However, diabetes mellitus (DM) is associated with increased residual platelet activity during dual antiplatelet treatment (DAPT) and DM patients have worse clinical outcomes after PCI as compared to non-DM.

OBJECTIVE

To evaluate efficacy and safety of short duration DAPT (S-DAPT) and long duration DAPT (L-DAPT) after drug eluting stent (DES) implantation in DM and non-DM patients.

METHODS

We searched Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify randomized controlled trials (RCTs) assessing the effect of S-DAPT versus L-DAPT after DES implantation in DM and non-DM patients. Efficacy endpoints were all-cause mortality, cardiac mortality, myocardial infarction (MI), stent thrombosis (ST), target vessel revascularization (TVR), and composite end point of net adverse clinical events (NACE) (all-cause mortality, cardiac mortality, MI, ST, TVR, stroke, major bleeding). Safety endpoints were major bleeding and stroke. Event rates were compared using a forest plot of relative risk using a random effects model.

RESULTS

We included eight RCTs that randomized 28,318 patients to S-DAPT versus L-DAPT (8234 DM and 20,084 non-DM). S-DAPT was associated with an increased rate of ST in non-DM patients [3.67 (2.04, 6.59)]. There was no significant difference in the rate of all-cause mortality, cardiac mortality, ST, MI, TVR, major bleeding, stroke and NACE with S-DAPT and L-DAPT in DM patients [1.19 (0.72-1.95); 1.25 (0.69, 2.25); 1.52 (0.70, 3.29); 1.33 (0.88, 2.01); 1.39 (0.89, 2.17); 0.92 (0.19, 4.42); 0.98 (0.29, 3.28); and 0.94 (0.57, 1.54) respectively]. Further, there was no significant difference in the rate of all-cause mortality, cardiac mortality, MI, TVR, major bleeding, stroke and NACE with S-DAPT and L-DAPT in non-DM patients [0.93 (0.58, 1.48); 0.75 (0.42, 1.35); 1.52 (0.81, 2.83); 0.99 (0.71, 1.39); 0.72 (0.28, 1.84); 1.01 (0.40, 2.56); and 1.01 (0.77, 1.32) respectively].

CONCLUSION

Compared to L-DAPT, S-DAPT was associated with significant increase in rate of ST in non-DM patients. Duration of DAPT had no significant impact on rates of all-cause mortality, cardiac mortality, MI, ST and TVR among DM patients.

2018 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Focused Update of the Guidelines for the Use of Antiplatelet Therapy

Antiplatelet therapy (APT) has become an important tool in the treatment and prevention of atherosclerotic events, particularly those associated with coronary artery disease. A large evidence base has evolved regarding the relationship between APT prescription in various clinical contexts and risk/benefit relationships. The Guidelines Committee of the Canadian Cardiovascular Society and Canadian Association of Interventional Cardiology publishes regular updates of its recommendations, taking into consideration the most recent clinical evidence. The present update to the 2011 and 2013 Canadian Cardiovascular Society APT guidelines incorporates new evidence on how to optimize APT use, particularly in situations in which few to no data were previously available. The recommendations update focuses on the following primary topics: (1) the duration of dual APT (DAPT) in patients who undergo percutaneous coronary intervention (PCI) for acute coronary syndrome and non-acute coronary syndrome indications; (2) management of DAPT in patients who undergo noncardiac surgery; (3) management of DAPT in patients who undergo elective and semiurgent coronary artery bypass graft surgery; (4) when and how to switch between different oral antiplatelet therapies; and (5) management of antiplatelet and anticoagulant therapy in patients who undergo PCI. For PCI patients, we specifically analyze the particular considerations in patients with atrial fibrillation, mechanical or bioprosthetic valves (including transcatheter aortic valve replacement), venous thromboembolic disease, and established left ventricular thrombus or possible left ventricular thrombus with reduced ejection fraction after ST-segment elevation myocardial infarction. In addition to specific recommendations, we provide values and preferences and practical tips to aid the practicing clinician in the day to day use of these important agents.

Dual antiplatelet therapy after percutaneous coronary intervention for stable CAD or ACS : Redefining the optimal duration of treatment

The duration and combination of dual antiplatelet therapy after coronary stent implantation, consisting of aspirin and a P2Y12 inhibitor, is among the most intensely investigated therapeutic strategies in cardiovascular medicine. While initial studies have mainly focused on the efficacy and safety of individual antithrombotic agents, the increased need for a personalized, risk-based approach to define the optimal duration of antithrombotic treatment according to the estimated ischemic and bleeding risk was then recognized. Recent recommendations for the optimal duration of antithrombotic combination therapies following coronary stent implantation in various clinical scenarios have substantially changed. The aim of the present article is to discuss the recent evidence from randomized clinical trials and observational studies with respect to antithrombotic treatment regimens in patients undergoing coronary artery stenting for stable coronary artery disease (CAD) or an acute coronary syndrome (ACS). We will focus on optimal treatment duration and a personalized approach based on ischemic and bleeding risk assessment.

Optimal duration of dual antiplatelet therapy after percutaneous coronary intervention or after acute coronary syndrome : Practical lessons from a review

To prevent recurrent ischaemic events, dual antiplatelet therapy (DAPT) is the standard of care after percutaneous coronary intervention and in the treatment of acute coronary syndrome. Recent evidence supports an adjusted DAPT duration in selected patients.The current paper aims to encourage cardiologists to actively search for patients benefiting from either shorter or prolonged duration DAPT and proposes an algorithm to identify patients who are likely to benefit from such an alternative strategy.Individualised DAPT duration should be considered in high-risk anatomic and/or clinical subgroups or in patients at increased haemorrhagic risk with low ischaemic risk. Both thrombotic and haemorrhagic risk should be assessed in all patients. In patients undergoing percutaneous coronary intervention, the interventional cardiologist could advise on the minimal duration of DAPT. However, in contrast to the minimum duration of DAPT for stent thrombosis prevention, longer duration DAPT is aimed at prevention of spontaneous myocardial infarction, and not at stent thrombosis, and thus the key to success is to treat the patient's overall thrombotic risk.The advice on the duration of DAPT must be documented in the patient's records and communicated with the treating physician and general practitioner. DAPT duration should be reassessed at least on a yearly basis.

Impact of early (3 months) dual antiplatelet treatment interruption prior to renal transplantation in patients with second-generation DES on perioperative stent thrombosis and MACEs

OBJECTIVE

Early cessation of dual antiplatelet therapy (DAPT) is related to stent thrombosis (ST). The use of second-generation everolimus- and zotarolimus-eluting stents is associated with low restenosis rates and short duration of clopidogrel usage. Non-cardiac surgery in recently stent-implanted patients is associated with major adverse cardiac events (MACEs). Chronic renal failure patients awaiting renal transplantation may also undergo coronary stent implantation prior to surgery. Here we aimed to investigate the safety of early (3 months) DAPT interruption in second-generation drug-eluting stent (DES)-implanted renal transplant recipients.

METHODS

In total, 106 previously stent-implanted chronic renal failure patients who underwent renal transplantation were retrospectively enrolled. Three groups were formed according to stent type and the duration of DAPT: early-interruption (3 months from DES implantation), lateinterruption (3-12 months from DES implantation), and bare-metal stent (BMS; at least 1 month from BMS implantation) groups.

RESULTS

Comparison among BMS, DES-early and DES-late groups indicated no difference in ST, myocardial infarction, death, and MACEs. In addition, no difference was observed in ST (p=0.998), myocardial infarction (p=0.998), death (p=0.999), and MACEs (p=0.998) between DES-early and DES-late groups.

CONCLUSION

Early (3 months) interruption of antiplatelet treatment with second-generation stents before renal transplantation seems to be safe and does not lead to increase in the occurrence of ST and MACEs.

Byrne R, Kastrati A, Schulz-Schüpke S. Validation of the DAPT score in patients randomized to 6 or 12 months clopidogrel after predominantly second-generation drug-eluting stents

The DAPT score is a recently-proposed decision tool for guiding optimal duration of dual antiplatelet therapy (DAPT). It showed modest accuracy in prior derivation and validation cohorts of patients with ≥12 months DAPT. This study was aimed to evaluate the validity of the DAPT score in a cohort of patients with 6 or 12 months DAPT after implantation of predominantly second-generation drug-eluting stents. We analyzed data of patients enrolled in the ISAR-SAFE trial. Patients were classified into low (<2) or high (≥2) DAPT score groups. Primary ischaemic (all-cause death, myocardial infarction, definite stent thrombosis or stroke) and bleeding (TIMI major or minor) outcomes were analyzed in the low and high DAPT score groups. Data of 3976 patients were available for DAPT score calculation. 2407 patients (60.5%) were classified in the low DAPT score group and 1569 patients (39.5%) in the high DAPT score group. In the low DAPT score group there were no significant differences between 6 and 12 months DAPT regarding ischaemic (1.0% vs. 1.4%, HR=0.74, 95% CI, 0.35–1.57; p=0.43) or bleeding outcomes (0.3% vs. 0.8%, HR=0.44, 95% CI, 0.13–1.42; p=0.17). In the high DAPT score group there were also no significant differences between 6 and 12 months DAPT regarding ischaemic (1.9% vs. 1.8%, HR=1.02, 95% CI, 0.49–2.14; p=0.96) or bleeding (0.3% vs. 0.5%, HR=0.51, 95% CI, 0.09–2.78; p=0.44) outcomes. In conclusion, the DAPT score failed to show a differential treatment effect in patients receiving 6 or 12 months DAPT after contemporary drug-eluting stent implantation.

Association Between Duration of Dual Antiplatelet Therapy and Angiographic Multivessel Disease on Outcomes in Patients Treated With Newer-Generation Drug-Eluting Stents

BACKGROUND

There is general agreement that the optimal duration of dual antiplatelet therapy (DAPT) in patients treated with drug-eluting stents should be individualized. We hypothesized that the extent of coronary artery disease may affect the clinical outcomes of DAPT.

METHODS AND RESULTS

We pooled patient-level data from 5 large, randomized trials comparing short-term DAPT with prolonged therapy. From the data, we identified 5476 patients who received newer-generation drug-eluting stents. Net adverse clinical event (NACE) was defined as a composite of all-cause mortality, myocardial infarction, stroke, or major bleeding. At 1 year, NACE had occurred in 171 patients (3.1%). Independent predictors of NACE were older age (>65 years), sex, presence of diabetes mellitus, left ventricular dysfunction (ejection fraction <40%), and angiographic multivessel disease. Multivessel disease and DAPT duration were significantly associated with NACE (P for interaction=0.002); the association was driven by the greater occurrence of myocardial infarction in patients with multivessel disease. In patients with multivessel disease, 6-month DAPT (versus 12-month DAPT) was associated with a higher incidence of myocardial infarction (adjusted hazard ratio=2.748; 95% confidence interval=1.375-5.491; P=0.004), compared with patients with single-vessel disease (P for interaction=0.001).

CONCLUSIONS

In patients treated with newer-generation drug-eluting stents, a significant interaction between DAPT strategy and multivessel disease was found regarding the occurrence of NACE at 1 year. Among adverse events, myocardial infarction was more frequent in 6-month DAPT than in 12-month DAPT in patients with multivessel disease.

Early Cessation of Adenosine Diphosphate Receptor Inhibitors Among Acute Myocardial Infarction Patients Treated With Percutaneous Coronary Intervention: Insights From the TRANSLATE-ACS Study (Treatment With Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome)

BACKGROUND

Guidelines recommend the use of adenosine diphosphate receptor inhibitor (ADPri) therapy for 1 year postacute myocardial infarction; yet, early cessation of therapy occurs frequently in clinical practice.

METHODS AND RESULTS

We examined 11 858 acute myocardial infarction patients treated with percutaneous coronary intervention discharged alive on ADPri therapy from 233 United States TRANSLATE-ACS study (Treatment With Adenosine Diphosphate Receptor Inhibitors: Longitudinal Assessment of Treatment Patterns and Events After Acute Coronary Syndrome) participating hospitals to determine the prevalence of early ADPri cessation (within 1 year), patient-reported reasons for cessation, and associated risk of major adverse cardiovascular events at 1 year. Overall, 2514 (21.2%) of percutaneous coronary intervention-treated patients stopped ADPri by 1 year postmyocardial infarction; the median time from discharge to cessation was 200.5 days (25th, 75th percentiles: 71, 340). Among those with early ADPri cessation, 53.9% received drug-eluting stents and had a median duration of 301 treatment days (25th, 75th percentiles: 137, 353); 33.3% of drug-eluting stent patients stopped treatment within 6 months compared with 64.2% of bare metal stent patients. Those discharged on prasugrel (versus clopidogrel) had a slightly higher likelihood of early ADPri cessation (23.2% versus 21.0%; P=0.03; adjusted hazard ratio, 1.28; 95% confidence interval, 1.17-1.40). Patient-reported reasons for early ADPri cessation included physician-recommended discontinuation (54%), as well as patient self-discontinuation, because of cost (19%), medication side effects (9%), and procedural interruption (10%). Using a time-dependent covariate model, early cessation of ADPri therapy was associated with increased major adverse cardiovascular event (adjusted hazard ratio, 1.40; 95% confidence interval, 1.19-1.65; P<0.0001).

CONCLUSIONS

One in 5 percutaneous coronary intervention-treated myocardial infarction patients stopped ADPri treatment within 1 year. Early cessation was associated with increased major adverse cardiovascular event risk.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01088503.

Dual antiplatelet therapy for secondary prevention of coronary artery disease

Dual antiplatelet therapy (DAPT) combining aspirin and a P2Y₁₂ receptor inhibitor has been consistently shown to reduce recurrent major adverse cardiovascular events (MACE) in patients with acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI) for stable coronary artery disease (CAD) compared with aspirin monotherapy, but at the expense of an increased risk of major bleeding. Nevertheless, the optimal duration of DAPT for secondary prevention of CAD remains uncertain, owing to the conflicting results of several large randomised trials. Among patients with stable CAD undergoing PCI with drug-eluting stents (DES), shorter durations of DAPT (3–6 months) were shown non-inferior to 12 or 24 months duration with respect to MACE, but reduced the rates of major bleeding. Contrariwise, prolonged DAPT durations (18–48 months) reduced the incidence of myocardial infarction and stent thrombosis, but at a cost of an increased risk of major bleeding and all-cause mortality. Until more evidence becomes available, the choice of optimal DAPT regimen and duration for patients with CAD requires a tailored approach based on the patient clinical presentation, baseline risk profile and management strategy. Future studies are however needed to identify patients who may derive benefit from shortened or extended DAPT courses for secondary prevention of CAD based on their individual ischaemic and bleeding risk. Based on limited evidence, 12 months duration of DAPT is currently recommended in patients with ACS irrespective of their management strategy, but large ongoing randomised trials are currently assessing the efficacy and safety of a short-term DAPT strategy (3–6 months) for patients with ACS undergoing PCI with newer generation DES. Finally, several ongoing, large-scale, randomised trials are challenging the current concept of DAPT by investigating P2Y₁₂ receptor inhibitors as single antiplatelet therapy and may potentially shift the paradigm of antiplatelet therapy after PCI in the near future. This article provides a contemporary state-of-the-art review of the current evidence on DAPT for secondary prevention of patients with CAD and its future perspectives.

Long-Term Use of Ticagrelor in Patients with Coronary Artery Disease

PURPOSE OF REVIEW

This review aims to summarize and discuss safety and effectiveness of the long-term use of ticagrelor in patients with coronary artery disease (CAD).

RECENT FINDINGS

Ticagrelor is an orally administered, direct, and reversible inhibitor of the P2Y₁₂-platelet receptor. Long-term use of ticagrelor in patients with previous myocardial infarction (MI) has been investigated in the PEGASUS-TIMI-54 trial. Overall, 21,162 patients with a spontaneous MI 1 to 3 years before randomization were randomly assigned to ticagrelor 90 mg bid, ticagrelor 60 mg bid, or placebo. Compared with placebo, both doses of ticagrelor showed that they were capable of significantly reducing the primary efficacy endpoint, although with a significant increase in TIMI major bleeding. Intracranial hemorrhage or fatal bleeding did not differ across groups. These findings establish clear benefit of DAPT extension with ticagrelor beyond 1 year of treatment, which comes with a tradeoff of clinically meaningful bleeding. Altogether, current evidence suggests that the duration of DAPT remains a patient-by-patient decision based on thrombotic and bleeding risk profiles.

Cost-Effectiveness of Different Durations of Dual-Antiplatelet Use After Percutaneous Coronary Intervention

BACKGROUND

There is uncertainty regarding the optimal duration of dual-antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). Our goal was to evaluate the cost-effectiveness of different durations of DAPT.

METHODS

We created a probabilistic patient-level Markov microsimulation model to assess the discounted lifetime costs and quality-adjusted life years (QALYs) of short duration (3-6 months: short-duration group) vs standard therapy (12 months: standard-duration group) vs prolonged therapy (30-36 months: long-duration group) in patients undergoing PCI.

RESULTS

The majority of patients in the model underwent PCI for stable angina (47.1%) with second-generation drug-eluting stents (62%) and were receiving clopidogrel (83.6%). Short-duration DAPT was the most effective strategy (7.163 ± 1.098 QALYs) compared with standard-duration DAPT (7.161 ± 1.097 QALYs) and long-duration DAPT (7.156 ± 1.097 QALYs). However, the magnitude of these differences was very small. Similarly, the average discounted lifetime cost was CAN$24,859 ± $6533 for short duration, $25,045 ± $6533 for standard duration, and $25,046 ± $6548 for long duration. Thus, in the base-case analysis, short duration was dominant, being more effective and less expensive. However, there was a moderate degree of uncertainty, because short duration was the preferred option in only ∼ 55% of simulations at a willingness to pay threshold of $50,000.

CONCLUSIONS

Based on a stable angina cohort receiving clopidogrel with second-generation stents, a short duration of DAPT was marginally better. However, the differences are minimal, and decisions about duration of therapy should be driven by clinical data, patient risk of adverse events, including bleeding, and cardiovascular events.