Aspirin-free strategies in cardiovascular disease and cardioembolic stroke prevention

Demystifying the Contemporary Role of 12-Month Dual Antiplatelet Therapy After Acute Coronary Syndrome

For almost two decades, 12-month dual antiplatelet therapy (DAPT) in acute coronary syndrome (ACS) has been the only class I recommendation on DAPT in American and European guidelines, which has resulted in 12-month durations of DAPT therapy being the most frequently implemented in ACS patients undergoing percutaneous coronary intervention (PCI) across the globe. Twelve-month DAPT was initially grounded in the results of the CURE (Clopidogrel in Unstable Angina to Prevent Recurrent Events) trial, which, by design, studied DAPT versus no DAPT rather than the optimal DAPT duration. The average DAPT duration in this study was 9 months, not 12 months. Subsequent ACS studies, which were not designed to assess DAPT duration, rather its composition (aspirin with prasugrel or ticagrelor compared with clopidogrel) were further interpreted as supportive evidence for 12-month DAPT duration. In these studies, the median DAPT duration was 9 or 15 months for ticagrelor and prasugrel, respectively. Several subsequent studies questioned the 12-month regimen and suggested that DAPT duration should either be fewer than 12 months in patients at high bleeding risk or more than 12 months in patients at high ischemic risk who can safely tolerate the treatment. Bleeding, rather than ischemic risk assessment, has emerged as a treatment modifier for maximizing the net clinical benefit of DAPT, due to excessive bleeding and no clear benefit of prolonged treatment regimens in high bleeding risk patients. Multiple DAPT de-escalation treatment strategies, including switching from prasugrel or ticagrelor to clopidogrel, reducing the dose of prasugrel or ticagrelor, and shortening DAPT duration while maintaining monotherapy with ticagrelor, have been consistently shown to reduce bleeding without increasing fatal or nonfatal cardiovascular or cerebral ischemic risks compared with 12-month DAPT. However, 12-month DAPT remains the only class-I DAPT recommendation for patients with ACS despite the lack of prospectively established evidence, leading to unnecessary and potentially harmful overtreatment in many patients. It is time for clinical practice and guideline recommendations to be updated to reflect the totality of the evidence regarding the optimal DAPT duration in ACS.

P2Y12 Receptor Inhibitor for Antiaggregant Therapies: From Molecular Pathway to Clinical Application

Platelets play a significant role in hemostasis, forming plugs at sites of vascular injury to limit blood loss. However, if platelet activation is not controlled, it can lead to thrombotic events, such as myocardial infarction and stroke. To prevent this, antiplatelet agents are used in clinical settings to limit platelet activation in patients at risk of arterial thrombotic events. However, their use can be associated with a significant risk of bleeding. An enhanced comprehension of platelet signaling mechanisms should facilitate the identification of safer targets for antiplatelet therapy. Over the past decade, our comprehension of the breadth and intricacy of signaling pathways that orchestrate platelet activation has expanded exponentially. Several recent studies have provided further insight into the regulation of platelet signaling events and identified novel targets against which to develop novel antiplatelet agents. Antiplatelet drugs are essential in managing atherothrombotic vascular disease. The current antiplatelet therapy in clinical practice is limited in terms of safety and efficacy. Novel compounds have been developed in response to patient variability and resistance to aspirin and/or clopidogrel. Recent studies based on randomized controlled trials and systematic reviews have definitively demonstrated the role of antiplatelet therapy in reducing the risk of cardiovascular events. Antiplatelet therapy is the recommended course of action for patients with established atherosclerosis. These studies compared monotherapy with a P2Y12 inhibitor versus aspirin for secondary prevention. However, in patients undergoing percutaneous coronary intervention, it is still unclear whether the efficacy of P2Y12 inhibitor monotherapy after a short course of dual antiplatelet therapy depends on the type of P2Y12 inhibitor. This paper focuses on the advanced-stage evaluation of several promising antiplatelet drugs.

Pharmacological effects of bioactive agents in earthworm extract: A comprehensive review

This review compiles information from the literature on the chemical composition, pharmacological effects, and molecular mechanisms of earthworm extract (EE) and suggests possibilities for clinical translation of EE. We also consider future trends and concerns in this domain. We summarize the bioactive components of EE, including G-90, lysenin, lumbrokinase, antimicrobial peptides, earthworm serine protease (ESP), and polyphenols, and detail the antitumor, antithrombotic, antiviral, antibacterial, anti-inflammatory, analgesic, antioxidant, wound-healing, antifibrotic, and hypoglycemic activities and mechanisms of action of EE based on existing in vitro and in vivo studies. We further propose the potential of EE for clinical translation in anticancer and lipid-modifying therapies, and its promise as source of a novel agent for wound healing and resistance to antibiotic tolerance. The earthworm enzyme lumbrokinase embodies highly effective anticoagulant and thrombolytic properties and has the advantage of not causing bleeding phenomena due to hyperfibrinolysis. Its antifibrotic properties can reduce the excessive accumulation of extracellular matrix. The glycolipoprotein extract G-90 can effectively scavenge reactive oxygen groups and protect cellular tissues from oxidative damage. Earthworms have evolved a well-developed defense mechanism to fight against microbial infections, and the bioactive agents in EE have shown good antibacterial, fungal, and viral properties in in vitro and in vivo experiments and can alleviate inflammatory responses caused by infections, effectively reducing pain. Recent studies have also highlighted the role of EE in lowering blood glucose. EE shows high medicinal value and is expected to be a source of many bioactive compounds.

Antiplatelet Therapy for Patients Who Have Undergone Revascularization Within the Past Year: Which Agents and for How Long?

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is recommended for at least 6 and 12 months following percutaneous coronary intervention with drug-eluting stents among patients with stable ischemic heart disease and acute coronary syndrome, respectively. Additional exposure to antiplatelet therapy reduces ischemic events but also increases bleeding risk. Conversely, shorter durations of DAPT are preferred among those at high bleeding risk. Hence, decisions surrounding duration of DAPT after revascularization should include clinical judgment, assessment of the risk of bleeding and ischemic events, and time after revascularization.

Ticagrelor or Clopidogrel Monotherapy vs Dual Antiplatelet Therapy After Percutaneous Coronary Intervention: A Systematic Review and Patient-Level Meta-Analysis

Importance

Among patients undergoing percutaneous coronary intervention (PCI), it remains unclear whether the treatment efficacy of P2Y12 inhibitor monotherapy after a short course of dual antiplatelet therapy (DAPT) depends on the type of P2Y12 inhibitor.

Objective

To assess the risks and benefits of ticagrelor monotherapy or clopidogrel monotherapy compared with standard DAPT after PCI.

Data Sources

MEDLINE, Embase, TCTMD, and the European Society of Cardiology website were searched from inception to September 10, 2023, without language restriction.

Study Selection

Included studies were randomized clinical trials comparing P2Y12 inhibitor monotherapy with DAPT on adjudicated end points in patients without indication to oral anticoagulation undergoing PCI.

Data Extraction and Synthesis

Patient-level data provided by each trial were synthesized into a pooled dataset and analyzed using a 1-step mixed-effects model. The study is reported following the Preferred Reporting Items for Systematic Review and Meta-Analyses of Individual Participant Data.

Main Outcomes and Measures

The primary objective was to determine noninferiority of ticagrelor or clopidogrel monotherapy vs DAPT on the composite of death, myocardial infarction (MI), or stroke in the per-protocol analysis with a 1.15 margin for the hazard ratio (HR). Key secondary end points were major bleeding and net adverse clinical events (NACE), including the primary end point and major bleeding.

Results

Analyses included 6 randomized trials including 25 960 patients undergoing PCI, of whom 24 394 patients (12 403 patients receiving DAPT; 8292 patients receiving ticagrelor monotherapy; 3654 patients receiving clopidogrel monotherapy; 45 patients receiving prasugrel monotherapy) were retained in the per-protocol analysis. Trials of ticagrelor monotherapy were conducted in Asia, Europe, and North America; trials of clopidogrel monotherapy were all conducted in Asia. Ticagrelor was noninferior to DAPT for the primary end point (HR, 0.89; 95% CI, 0.74-1.06; P for noninferiority = .004), but clopidogrel was not noninferior (HR, 1.37; 95% CI, 1.01-1.87; P for noninferiority > .99), with this finding driven by noncardiovascular death. The risk of major bleeding was lower with both ticagrelor (HR, 0.47; 95% CI, 0.36-0.62; P < .001) and clopidogrel monotherapy (HR, 0.49; 95% CI, 0.30-0.81; P = .006; P for interaction = 0.88). NACE were lower with ticagrelor (HR, 0.74; 95% CI, 0.64-0.86, P < .001) but not with clopidogrel monotherapy (HR, 1.00; 95% CI, 0.78-1.28; P = .99; P for interaction = .04).

Conclusions and Relevance

This systematic review and meta-analysis found that ticagrelor monotherapy was noninferior to DAPT for all-cause death, MI, or stroke and superior for major bleeding and NACE. Clopidogrel monotherapy was similarly associated with reduced bleeding but was not noninferior to DAPT for all-cause death, MI, or stroke, largely because of risk observed in 1 trial that exclusively included East Asian patients and a hazard that was driven by an excess of noncardiovascular death.

Aspirin-free antiplatelet strategies after percutaneous coronary interventions

Dual antiplatelet therapy (DAPT) with aspirin and a platelet P2Y12 receptor inhibitor is the standard antithrombotic treatment after percutaneous coronary interventions (PCI). Several trials have challenged guideline-recommended DAPT after PCI by testing the relative clinical effect of an aspirin-free antiplatelet approach-consisting of P2Y12 inhibitor monotherapy after a short course (mostly 1-3 months) of DAPT-among patients undergoing PCI without a concomitant indication for oral anticoagulation (OAC). Overall, these studies have shown P2Y12 inhibitor monotherapy after short DAPT to be associated with a significant reduction in the risk of bleeding without an increase in thrombotic or ischaemic events compared with continued DAPT. Moreover, the effects of the P2Y12 inhibitor monotherapy without prior DAPT or following a very short course of DAPT after PCI are being investigated in emerging studies, of which one has recently reported unfavourable efficacy results associated with the aspirin-free approach compared with conventional DAPT. Finally, P2Y12 inhibitor alone has been compared with aspirin alone as chronic therapy after DAPT discontinuation, thus challenging the historical role of aspirin as a standard of care for secondary prevention following PCI. A thorough understanding of study designs, populations, treatments, results, and limitations of trials testing P2Y12 inhibitor monotherapy vs. DAPT or vs. aspirin is required to consider adopting this treatment in clinical practice. This review addresses the use of aspirin-free antiplatelet strategies among patients undergoing PCI without a concomitant indication for OAC, providing an overview of clinical evidence, guideline indications, practical implications, ongoing issues, and future perspectives.

P2Y12 inhibitor monotherapy versus dual antiplatelet therapy in patients with acute coronary syndromes undergoing coronary stenting: rationale and design of the NEOMINDSET Trial

Dual antiplatelet therapy (DAPT) is currently the standard of care after percutaneous coronary intervention (PCI). Recent studies suggest that reducing DAPT to 1-3 months followed by an aspirin-free single antiplatelet therapy (SAPT) strategy with a potent P2Y12 inhibitor is safe and associated with less bleeding. However, to date, no randomised trial has tested the impact of initiating SAPT immediately after PCI, particularly in patients with acute coronary syndromes (ACS). NEOMINDSET is a multicentre, randomised, open-label trial with a blinded outcome assessment designed to compare SAPT versus DAPT in 3,400 ACS patients undergoing PCI with the latest-generation drug-eluting stents (DES). After successful PCI and up to 4 days following hospital admission, patients are randomised to receive SAPT with a potent P2Y12 inhibitor (ticagrelor or prasugrel) or DAPT (aspirin plus a potent P2Y12 inhibitor) for 12 months. Aspirin is discontinued immediately after randomisation in the SAPT group. The choice between ticagrelor and prasugrel is at the investigator's discretion. The primary hypothesis is that SAPT will be non-inferior to DAPT with respect to the composite endpoint of all-cause mortality, stroke, myocardial infarction or urgent target vessel revascularisation, but superior to DAPT on rates of bleeding defined by Bleeding Academic Research Consortium 2, 3 or 5 criteria. NEOMINDSET is the first study that is specifically designed to test SAPT versus DAPT immediately following PCI with DES in ACS patients. This trial will provide important insights on the efficacy and safety of withdrawing aspirin in the early phase of ACS. (ClinicalTrials.gov: NCT04360720).

P2Y12 Inhibitor or Aspirin Monotherapy for Secondary Prevention of Coronary Events

BACKGROUND

Aspirin is the only antiplatelet agent with a Class I recommendation for long-term prevention of cardiovascular events in patients with coronary artery disease (CAD). There is inconsistent evidence on how it compares with alternative antiplatelet agents.

OBJECTIVES

This study compared P2Y12 inhibitor monotherapy vs aspirin in patients with CAD.

METHODS

We conducted a patient-level meta-analysis of randomized trials comparing P2Y12 inhibitor monotherapy vs aspirin monotherapy for the prevention of cardiovascular events in patients with established CAD. The primary outcome was the composite of cardiovascular death, myocardial infarction, and stroke. Prespecified key secondary outcomes were major bleeding and net adverse clinical events (the composite of the primary outcome and major bleeding). Data were pooled in a 1-step meta-analysis.

RESULTS

Patient-level data were obtained from 7 trials. Overall, 24,325 participants were available for analysis, including 12,178 patients assigned to receive P2Y12 inhibitor monotherapy (clopidogrel in 7,545 [62.0%], ticagrelor in 4,633 [38.0%]) and 12,147 assigned to receive aspirin. Risk of the primary outcome was lower with P2Y12 inhibitor monotherapy compared with aspirin over 2 years (HR: 0.88; 95% CI: 0.79-0.97; P = 0.012), mainly owing to less myocardial infarction (HR: 0.77; 95% CI: 0.66-0.90; P < 0.001). Major bleeding was similar (HR: 0.87; 95% CI: 0.70-1.09; P = 0.23) and net adverse clinical events were lower (HR: 0.89; 95% CI: 0.81-0.98; P = 0.020) with P2Y12 inhibitors. The treatment effect was consistent across prespecified subgroups and types of P2Y12 inhibitors.

CONCLUSIONS

Given its superior efficacy and similar overall safety, P2Y12 inhibitor monotherapy might be preferred over aspirin monotherapy for long-term secondary prevention in patients with established CAD. (P2Y12 Inhibitor or Aspirin Monotherapy as Secondary Prevention in Patients With Coronary Artery Disease: An Individual Patient Data Meta-Analysis of Randomized Trials [PANTHER collaborative initiative]; CRD42021290774).

Single antiplatelet therapy directly after percutaneous coronary intervention in non-ST-segment elevation acute coronary syndrome patients: the OPTICA study

BACKGROUND

Early P2Y12 inhibitor monotherapy has emerged as a promising alternative to 12 months of dual antiplatelet therapy following percutaneous coronary intervention (PCI).

AIMS

In this single-arm pilot study, we evaluated the feasibility and safety of ticagrelor or prasugrel monotherapy directly following PCI in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

METHODS

Patients received a loading dose of ticagrelor or prasugrel before undergoing platelet function testing and subsequent PCI using new-generation drug-eluting stents. The stent result was adjudicated with optical coherence tomography in the first 35 patients. Ticagrelor or prasugrel monotherapy was continued for 12 months. The primary ischaemic endpoint was the composite of all-cause mortality, myocardial infarction, definite or probable stent thrombosis or stroke within 6 months. The primary bleeding endpoint was Bleeding Academic Research Consortium type 2, 3 or 5 bleeding within 6 months.

RESULTS

From March 2021 to March 2022, 125 patients were enrolled, of whom 75 ultimately met all in- and exclusion criteria (mean age 64.5 years, 29.3% women). Overall, 70 out of 75 (93.3%) patients were treated with ticagrelor or prasugrel monotherapy directly following PCI. The primary ischaemic endpoint occurred in 3 (4.0%) patients within 6 months. No cases of stent thrombosis or spontaneous myocardial infarction occurred. The primary bleeding endpoint occurred in 7 (9.3%) patients within 6 months.

CONCLUSIONS

This study provides first-in-human evidence that P2Y12 inhibitor monotherapy directly following PCI for NSTE-ACS is feasible, without any overt safety concerns, and highlights the need for randomised controlled trials comparing direct P2Y12 inhibitor monotherapy with the current standard of care.

Advances in the available pharmacotherapy for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation

INTRODUCTION

Non-ST-segment elevation acute coronary syndromes (NSTE-ACS), including non-ST-segment-elevation myocardial infarction (NSTEMI) and unstable angina, represent a leading cause of mortality worldwide, with important socio-economic consequences. NSTEMI accounts for the majority of acute coronary syndromes and usually develops on the background of a nonocclusive thrombus. We searched for relevant literature in the field in PubMed and clinicaltrials.gov as of July 2022.

AREAS COVERED

A number of pharmacotherapies are currently available for treatment and secondary prevention, mainly including antithrombotic, lipid-lowering and anti-inflammatory drugs. Pretreatment with aspirin, anticoagulant and statin therapy is of key importance in the preprocedural phase, while pretreating with an oral P2Y12 inhibitor is not routinely indicated in patients undergoing early invasive management. For patients undergoing percutaneous coronary revascularization, pharmacotherapy essentially consists of antithrombotic drugs, which should be carefully selected. Finally, antithrombotic, lipid-lowering and anti-inflammatory drugs are important components of long-term secondary prevention after a NSTE-ACS.

EXPERT OPINION

This article reviews the evidence supporting recommendation on pharmacotherapy in patients presenting with a NSTE-ACS. Several randomized clinical trials are still ongoing and are expected to further inform scientific knowledge and clinical practice, with the final aim to improve the treatment of NSTE-ACS patients.

Antithrombotic Management in AF Patients Following Percutaneous Coronary Intervention: A European Perspective

AF is a highly prevalent disease, often requiring long-term oral anticoagulation to prevent stroke or systemic embolism. Coronary artery disease, which is common among AF patients, is often referred for myocardial revascularisation by percutaneous coronary intervention (PCI), which requires dual antiplatelet therapy to minimise the risk of stent-related complications. The overlap of AF and PCI is a clinical conundrum, especially in the early post-procedural period, when both long-term oral anticoagulation and dual antiplatelet therapy are theoretically indicated as a triple antithrombotic therapy. However, stacking drugs is not a desirable option because of the increased bleeding risk. Several strategies have been investigated to mitigate this concern, including shortening triple antithrombotic therapy duration and switching to a dual antithrombotic regimen. This review analyses the mechanisms underlying thrombotic complications in AF-PCI, summarises evidence surrounding antithrombotic therapy regimens and reports and comments on the latest European guidelines.

P2Y12 Inhibitor Monotherapy versus Conventional Dual Antiplatelet Therapy in Patients with Acute Coronary Syndrome after Percutaneous Coronary Intervention: A Meta-Analysis

P2Y12 inhibitor monotherapy is a feasible alternative treatment for patients after percutaneous coronary intervention (PCI) in the modern era. Clinical trials have shown that it could lower the risk of bleeding complications without increased ischemic events as compared to standard dual antiplatelet therapy (DAPT). However, the efficacy and safety of this novel approach among patients with acute coronary syndrome (ACS) are controversial because they have a much higher risk for recurrent ischemic events. The purpose of this study is to evaluate the efficacy and safety of this novel approach among patients with ACS. We conducted a meta-analysis of randomized controlled trials that compared P2Y12 inhibitor monotherapy with 12-month DAPT in ACS patients who underwent PCI with stent implantation. PubMed, Embase, the Cochrane library database, ClinicalTrials.gov, and other three websites were searched for data from the earliest report to July 2022. The primary efficacy outcome was major adverse cardiovascular and cerebrovascular events (MACCE), a composite of all-cause mortality, myocardial infarction, stent thrombosis, or stroke. The primary safety outcome was major or minor bleeding events. The secondary endpoint was net adverse clinical events (NACE), defined as a composite of major bleeding and adverse cardiac and cerebrovascular events. Five randomized controlled trials with a total of 21,034 patients were included in our meta-analysis. The quantitative analysis showed a significant reduction in major or minor bleeding events in patients treated with P2Y12 inhibitor monotherapy as compared with standard DAPT(OR: 0.59, 95% CI: 0.46-0.75, p < 0.0001) without increasing the risk of MACCE (OR: 0.98, 95% CI: 0.86-1.13, p = 0.82). The NACE was favorable in the patients treated with P2Y12 inhibitor monotherapy (OR: 0.82, 95% CI: 0.73-0.93, p = 0.002). Of note, the overall clinical benefit of P2Y12 inhibitor monotherapy was quite different between ticagrelor and clopidogrel. The incidence of NACE was significantly lower in ticagrelor monotherapy as compared with DAPT (OR: 0.79, 95% CI: 0.68-0.91), but not in clopidogrel monotherapy (OR: 1.14, 95% CI: 0.79-1.63). Both clopidogrel and ticagrelor monotherapy showed a similar reduction in bleeding complications (OR: 0.46, 95% CI: 0.22-0.94; OR: 0.60, 95% CI: 0.44-0.83, respectively). Although statistically insignificant, the incidence of MACCE was numerically higher in clopidogrel monotherapy as compared with standard DAPT (OR: 1.50, 95% CI: 0.99-2.28, p = 0.06). Based on these findings, P2Y12 inhibitor monotherapy with ticagrelor would be a better choice of medical treatment for ACS patients after PCI with stent implantation in the current era.

The protective effect of rivaroxaban with or without aspirin on inflammation, oxidative stress, and platelet reactivity in isoproterenol-induced cardiac injury in rats

Coronary artery diseases are principal sources of mortality and disability in global human population. Progressively, rivaroxaban is being evaluated for the prevention of atherosclerotic thrombi, particularly with anti-platelet agents. Hence, the current report aimed to investigate the cardioprotective effect of rivaroxaban on isoproterenol (ISO)-induced cardiac injury model in rats and the possible synergistic effect when combined with aspirin. Male Wistar rats were randomly assigned into five different groups. Cardiac injury was induced by subcutaneous injection of ISO (85 mg/kg) for 2 consecutive days. Rat tail bleeding time was performed prior to sacrifice. Cardiac enzymes, platelet activity, inflammatory, and oxidative stress biomarkers levels were measured using enzyme-linked immunoassay (ELISA). Pre-administration of rivaroxaban alone and on combination with aspirin prevented ISO-induced increase in cardiac thiobarbituric acid reactive substances (TBARS), interleukin 6 (IL-6), and thromboxane B2 (TXB2) levels. Moreover, a significant prolongation of bleeding time was demonstrated among aspirin, rivaroxaban, and aspirin plus rivaroxaban treated groups. On the other hand, the combination treatment of aspirin plus rivaroxaban showed no marked difference in these biomarkers and bleeding time relative to either drug administered separately. However, a prominent decrease of cardiac 6-keto prostaglandin F1α (6-Keto-PGF1α) level was displayed in the combination treatment when compared with ISO and rivaroxaban-treated groups, whereas no significant improvement was seen in cardiac glycoprotein V (GPV) levels except in aspirin-treated group. The study results demonstrated that rivaroxaban decreases cardiac oxidative stress, inflammation, and platelets reactivity. However, the addition of rivaroxaban to aspirin did not seem to show synergistic antioxidant, anti-inflammatory, or antiplatelet effect.

Aspirin Versus Clopidogrel for Long-Term Maintenance Monotherapy After Percutaneous Coronary Intervention: The HOST-EXAM Extended Study

BACKGROUND

Long-term outcomes of antiplatelet monotherapy in patients who receive percutaneous coronary intervention are unknown. The HOST-EXAM (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Extended Antiplatelet Monotherapy) Extended study reports the posttrial follow-up results of the original HOST-EXAM trial.

METHODS

From March 2014 through May 2018, 5438 patients who maintained dual antiplatelet therapy without clinical events for 12±6 months after percutaneous coronary intervention with drug-eluting stents were randomly assigned in a 1:1 ratio to receive clopidogrel (75 mg once daily) or aspirin (100 mg once daily). The primary end point (a composite of all-cause death, nonfatal myocardial infarction, stroke, readmission attributable to acute coronary syndrome, and Bleeding Academic Research Consortium type 3 or greater bleeding), secondary thrombotic end point (cardiac death, nonfatal myocardial infarction, ischemic stroke, readmission attributable to acute coronary syndrome, and definite or probable stent thrombosis), and bleeding end point (Bleeding Academic Research Consortium type 2 or greater bleeding) were analyzed during the extended follow-up period. Analysis was performed on the per-protocol population (2431 patients in the clopidogrel group and 2286 patients in the aspirin group).

RESULTS

During a median follow-up of 5.8 years (interquartile range, 4.8-6.2 years), the primary end point occurred in 12.8% and 16.9% in the clopidogrel and aspirin groups, respectively (hazard ratio, 0.74 [95% CI, 0.63-0.86]; P<0.001). The clopidogrel group had a lower risk for the secondary thrombotic end point (7.9% versus 11.9%; hazard ratio, 0.66 [95% CI, 0.55-0.79]; P<0.001) and secondary bleeding end point (4.5% versus 6.1%; hazard ratio, 0.74 [95% CI, 0.57-0.94]; P=0.016). There was no significant difference in the incidence of all-cause death between the 2 groups (6.2% versus 6.0%; hazard ratio, 1.04 [95% CI, 0.82-1.31]; P=0.742). Landmark analysis at 2 years showed that the beneficial effect of clopidogrel was consistent throughout the follow-up period.

CONCLUSIONS

During an extended follow-up of >5 years after randomization, clopidogrel monotherapy compared with aspirin monotherapy was associated with lower rates of the composite net clinical outcome in patients without clinical events for 12±6 months after percutaneous coronary intervention with drug-eluting stents.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02044250.

Timing, Selection, Modulation, and Duration of P2Y12 Inhibitors for Patients With Acute Coronary Syndromes Undergoing PCI

Dual antiplatelet therapy with aspirin and the oral P2Y₁₂ inhibitor clopidogrel as the cornerstone of treatment for patients with an acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) was firstly established in 2001. Soon thereafter, the newer-generation P2Y₁₂ inhibitors prasugrel and ticagrelor became commercially available. The clinical management of ACS patients undergoing PCI has evolved significantly in the last 2 decades, with a shift toward more rapid invasive management, broader use of drug-eluting stents, and the increasing recognition that major bleeding due to antiplatelet therapy is detrimental. In this ever-changing scenario, numerous studies have addressed 4 main questions regarding P2Y₁₂ inhibition in ACS patients undergoing PCI: timing, selection, modulation, and duration. This paper reviews the latest evidence surrounding these topical questions, with a focus on efficacy and safety data, practice guidelines, and residual areas of uncertainty.

Short-term dual antiplatelet therapy for 1-3 months after percutaneous coronary intervention using drug eluting stents: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The optimal dual antiplatelet therapy (DAPT) duration and regimen in patients undergoing percutaneous coronary intervention (PCI) using current generation drug eluting stents (DES) is still unclear.

AIMS

To compare the safety and efficacy of short-term DAPT (S-DAPT) with longer duration DAPT (l-DAPT) after contemporary PCI.

METHODS

We searched for studies comparing S-DAPT (≤3 months) followed by single antiplatelet therapy (SAPT) with aspirin or a P2Y12 inhibitor against L-DAPT (6-12 months) after PCI with current generation DES. Primary end-points of interest were major bleeding and stent thrombosis (ST) at 1 year. Random-effects meta-analyses were performed to calculate odds ratios with 95% CIs.

RESULTS

Eleven RCTs (n = 48,946) were included in the primary analysis. Major bleeding was significantly lower with S-DAPT (n = 24,424) (odd ratio [OR 0.65; 95% confidence interval, CI 0.52-0.80]) compared with L-DAPT (n = 24,486). There were no differences in ST between the two groups [OR 1.26; 95% CI 0.97-1.63]. There were no significant differences in risks of all-cause death, cardiovascular death or myocardial infarction between S-DAPT and L-DAPT groups. In a subgroup analysis, there was borderline significantly higher ST with 1 month S-DAPT [1.39; 1.0-1.92], but not with 3 months S-DAPT [1.07; 0.70-1.64], when compared to L-DAPT. Finally, there were no significant treatment interactions observed when trials using SAPT with aspirin were compared with those using P2Y12 inhibitor monotherapy.

CONCLUSION

Among patients undergoing current generation DES implantation, S-DAPT for 1-3 months reduces major bleeding without an increase in ischemic events compared with L-DAPT. Three months S-DAPT might provide a better risk-benefit profile based on current analysis. Further study is needed to define the SAPT of choice after 1-3 months DAPT.

Ticagrelor with and without aspirin in patients with a prior coronary artery bypass graft undergoing percutaneous coronary intervention: the TWILIGHT-CABG study

BACKGROUND

Prior coronary artery bypass graft surgery (CABG) patients undergoing percutaneous coronary intervention (PCI) are often older and present with multiple comorbidities. Ticagrelor monotherapy after a short course of dual antiplatelet therapy (DAPT) has emerged as an effective bleeding-avoidance strategy among high-risk patients.

AIMS

We aimed to examine the effects of ticagrelor with or without aspirin in prior CABG patients undergoing PCI within the TWILIGHT trial.

METHODS

After 3 months of ticagrelor plus aspirin, patients were randomised to either aspirin or placebo, in addition to ticagrelor, for 12 months and compared by prior CABG status. The primary endpoint was Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding. The key secondary endpoint was all-cause death, myocardial infarction (MI), or stroke.

RESULTS

Out of 7,119 patients, a total of 703 (10.8%) patients had prior CABG within the randomised cohort. Prior CABG patients had more comorbidities and a higher incidence of BARC type 2, 3, or 5 bleeding and death, MI or stroke at 1 year after randomisation, compared with patients without prior CABG. Ticagrelor monotherapy was associated with significantly less BARC 2, 3, or 5 bleeding among prior CABG patients compared with DAPT (4.9% vs 9.6%, hazard ratio [HR] 0.50, 95% confidence interval [CI]: 0.28 to 0.90; pinteraction=0.676) and similar rates of death, MI or stroke (10.0% vs 8.7%, HR 1.14, 95% CI: 0.70 to 1.87; pinteraction=0.484). When comparing target vessel type, treatment effects were consistent among graft- and native-vessel interventions.

CONCLUSIONS

In high-risk patients with prior CABG, ticagrelor monotherapy reduced bleeding without compromising ischaemic outcomes compared with ticagrelor plus aspirin.

P2Y12 inhibitor monotherapy in patients undergoing percutaneous coronary intervention

For 20 years, dual antiplatelet therapy (DAPT), consisting of the combination of aspirin and a platelet P2Y₁₂ receptor inhibitor, has been the gold standard of antithrombotic pharmacology after percutaneous coronary intervention (PCI). In the past 5 years, several investigations have challenged this paradigm by testing the efficacy and safety of P2Y₁₂ inhibitor monotherapy (that is, without aspirin) following a short course of DAPT. Collectively, these studies suggested a reduction in the risk of major bleeding and no significant increase in thrombotic or ischaemic events compared with guideline-recommended DAPT. Current recommendations are evolving to inform clinical practice on the ideal candidates for P2Y₁₂ inhibitor monotherapy after PCI. Generalizing the results of studies of P2Y₁₂ inhibitor monotherapy requires a thorough understanding of their design, populations, interventions, comparators and results. In this Review, we provide an up-to-date overview on the use of P2Y₁₂ inhibitor monotherapy after PCI, including supporting pharmacodynamic and clinical evidence, practical recommendations and future directions.

Clinical pharmacology of antiplatelet drugs

INTRODUCTION

Platelets play a key role in arterial thrombosis and antiplatelet therapy is pivotal in the treatment of cardiovascular disease. Current antiplatelet drugs target different pathways of platelet activation and show specific pharmacodynamic and pharmacokinetic characteristics, implicating clinically relevant drug-drug interactions.

AREAS COVERED

This article reviews the role of platelets in hemostasis and cardiovascular thrombosis, and discusses the key pharmacodynamics, drug-drug interactions and reversal strategies of clinically used antiplatelet drugs.

EXPERT OPINION

Antiplatelet therapies target distinct pathways of platelet activation: thromboxane A₂ synthesis, adenosine diphosphate-mediated signaling, integrin α_IIbβ₃ (GPIIb/IIIa), thrombin-mediated platelet activation via the PAR1 receptor and phosphodiesterases. Key clinical drug-drug interactions of antiplatelet agents involve acetylsalicylic acid - ibuprofen, clopidogrel - omeprazole, and morphine - oral P2Y₁₂ inhibitors, all of which lead to an attenuated antiplatelet effect. Platelet function and genetic testing and the use of scores (ARC-HBR, PRECISE-DAPT, ESC ischemic risk definition) may contribute to a more tailored antiplatelet therapy. High on-treatment platelet reactivity presents a key problem in the acute management of ST-elevation myocardial infarction (STEMI). A treatment strategy involving early initiation of an intravenous antiplatelet agent may be able to bridge the gap of insufficient platelet inhibition in high ischemic risk patients with STEMI.

P2Y12-inhibitor monotherapy after coronary stenting: are all P2Y12-inhibitors equal?

INTRODUCTION

P2Y₁₂-inhibitor monotherapy following 1-3 months of dual antiplatelet therapy (DAPT) reduces (major) bleeding without an apparent increase in ischemic events and has therefore emerged as an alternative to 6-12 months of DAPT following percutaneous coronary intervention (PCI). However, there are important differences between the available P2Y₁₂-inhibitors (clopidogrel, prasugrel, and ticagrelor) as agents of choice for P2Y₁₂-inhibitor monotherapy.

AREAS COVERED

This review critically appraises the evidence for P2Y₁₂-inhibitor monotherapy after PCI using either clopidogrel, prasugrel, or ticagrelor. Furthermore, we discuss ongoing trials and future directions for research.

EXPERT OPINION

P2Y₁₂-inhibitor monotherapy following 1-3 months of DAPT is an alternative to 6-12 months of DAPT following PCI. Ticagrelor may be considered the current preferred option due to its reliable effect on platelet reactivity and its predominant use in clinical trials. Prasugrel could serve as a useful substitute for those not tolerating ticagrelor, but more research into prasugrel monotherapy is warranted. Alternatively, clopidogrel can be used, although there are concerns of high platelet reactivity, especially when genotyping and/or platelet function testing are not used. Future research will need to address the minimal duration of DAPT before switching to P2Y₁₂-inhibitor monotherapy and what the optimal antithrombotic therapy beyond 12 months is.

Dual antiplatelet therapy duration after percutaneous coronary intervention using drug eluting stents in high bleeding risk patients: A systematic review and meta-analysis

BACKGROUND

Optimal dual antiplatelet therapy (DAPT) duration in patients at high bleeding risk (HBR) is not fully defined. We aimed to compare the safety and effectiveness of short-term DAPT (S-DAPT) with longer duration DAPT (L-DAPT) after percutaneous coronary intervention (PCI) with drug eluting stents (DES) in patients at HBR.

METHODS

We searched for studies comparing S-DAPT (≤3 months) followed by aspirin or P2Y 12 inhibitor monotherapy against L-DAPT (6-12 months) after PCI in HBR patients. Primary end points of interest were major bleeding and myocardial infarction (MI). Random-effects meta-analyses were performed to calculate odds ratios with 95% CIs.

RESULTS

Six randomized trials and 3 propensity-matched studies (n = 16,848) were included in the primary analysis. Compared with L-DAPT (n = 8,422), major bleeding was lower with S-DAPT (n = 8,426) [OR 0.68; 95% CI 0.51-0.89] whereas MI did not differ significantly between the 2 groups [1.16; 0.94-1.44]. There were no significant differences in risks of death, stroke or stent thrombosis (ST) between S-DAPT and L-DAPT groups. These findings were consistent when propensity-matched studies were analysed separately. Finally, there was a numerically higher, albeit statistically non-significant, ST in the S-DAPT arm of patients without an indication for OAC [1.98; 0.86-4.58].

CONCLUSIONS

Among HBR patients undergoing current generation DES implantation, S-DAPT reduces bleeding without an increased risk of death or MI compared with L-DAPT. More research is needed to (1) evaluate risks of late ST after 1 to 3 months DAPT among patients with high ischemic and bleeding risks, (2) defining the SAPT of choice after 1 to 3 months DAPT.

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.

Polysaccharide-protein complex from coelomic fluid of Dendrobaena veneta earthworm exerts a multi-pathway antiplatelet effect without coagulopathy and cytotoxicity

There is a pressing need to identify novel antiplatelet agents, an alternative to acetylsalicylic acid and thienopyridines, to broaden the prevention of cardiovascular events, the leading cause of global morbidity and mortality. Invertebrate coelomocytes structurally and functionally resemble the thrombocyte-like cells of vertebrates; therefore, the coelomic fluid in which they are suspended may contain agents controlling their clumping abilities. However, whether coelomocytes-free coelomic fluid may also affect human platelet activities was not a subject of any study. This study aimed to screen the in vitro antiplatelet and anticoagulant activities of the polysaccharide-protein complex from Dendrobaena veneta coelomic fluid (25-100 µg/mL) (PPC-DV). All tested fluid concentrations induced significant (42.4-52.5%) inhibition of adenosine-5'-diphosphate (ADP)-induced aggregation of human platelets at a level comparable to that of 140 µmol/L acetylsalicylic acid. Its relevant antiplatelet effect (27.2-45.9%) was also evidenced in the thrombin receptor-activating peptide-6 (TRAP-6) assay. Moreover, 50 and 100 µg/mL of PPC-DV inhibited arachidonic acid-inducible aggregation. No coagulopathic or cytotoxic effects of PPC-DV were observed. The study indicates that PPC-DV, at a concentration of at least 50 µg/mL, exerts a favorable antiplatelet effect by targeting at least three pathways (P2Y₁₂ receptor, cyclooxygenase-1, and protease-activated receptor-1), justifying further experimental and clinical investigations on its use in cardiovascular disease prevention.

Ticagrelor With or Without Aspirin in Chinese Patients Undergoing Percutaneous Coronary Intervention: A TWILIGHT China Substudy

BACKGROUND

The risk/benefit tradeoff of dual antiplatelet therapy after percutaneous coronary intervention may vary in East Asian patients as compared with their non-East Asian counterparts.

METHODS

The double-blind, placebo-controlled, randomized TWILIGHT trial (Ticagrelor With Aspirin or Alone in High-Risk Patients After Coronary Intervention) enrolled patients undergoing high-risk percutaneous coronary intervention. After 3 months of treatment with ticagrelor plus aspirin, event-free and adherent patients remained on ticagrelor and were randomly assigned to receive aspirin or placebo for 1 year. The primary end point was Bleeding Academic Research Consortium type 2, 3, or 5 bleeding; the key secondary end point was the first occurrence of death from any cause, nonfatal myocardial infarction, or nonfatal stroke.

RESULTS

Of 9006 enrolled and 7119 randomized patients in TWILIGHT, 1169 patients (13.0%) were enrolled at 27 Chinese sites in this prespecified substudy, of whom 1028 (14.4%) patients were randomized after 3 months. The incidence of the primary end point was 6.2% in the ticagrelor+aspirin group versus 3.5% in the ticagrelor+placebo group between randomization and 1 year (hazard ratio, 0.56 [95% CI, 0.31-0.99]; P=0.048). The key secondary end point occurred in 3.4% of patients in the ticagrelor+aspirin group versus 2.4% in the ticagrelor+placebo group (hazard ratio, 0.70 [95% CI, 0.33-1.46]; P=0.34). There was no interaction between the region of randomization (China versus the rest of the world) and randomized treatment assignment in terms of the primary or key secondary end points.

CONCLUSIONS

Ticagrelor monotherapy significantly reduced clinically relevant bleeding without increasing ischemic events as compared with ticagrelor plus aspirin in Chinese patients undergoing high-risk percutaneous coronary intervention.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02270242.

Antiplatelet therapy after percutaneous coronary intervention

Antiplatelet therapy is key to reducing local thrombotic complications and systemic ischaemic events among patients undergoing percutaneous coronary interventions (PCI), but it is inevitably associated with increased bleeding. The continuous refinement in stent technologies, together with the high incidence of ischaemic recurrences after PCI and the understanding of prognostic implications associated with bleeding, have led to a substantial evolution in antiplatelet treatment regimens over the past decades. Numerous investigations have been conducted to better stratify patients undergoing PCI according to their ischaemic and bleeding risks and to implement antithrombotic regimens accordingly. Evidence from these investigations have resulted in a number of antithrombotic treatment options as recommended by recent guidelines. In this State-of-the-Art review we provide the rationale, summarise the evidence, and discuss current and future directions of antiplatelet treatment regimens after PCI.

Platelet P2Y12 inhibiting therapy in adjunct to vascular dose of rivaroxaban or aspirin: A pharmacodynamic study of dual pathway inhibition versus dual antiplatelet therapy

AIM

Dual-pathway inhibition (DPI) by adding a vascular dose of rivaroxaban to a single antiplatelet agent has emerged as a promising antithrombotic strategy. However, in most studies the antiplatelet agent of choice used in adjunct to a vascular dose of rivaroxaban was aspirin, and data with a P2Y12 inhibitor and how this DPI regimen compares with standard dual antiplatelet therapy (DAPT) is limited.

METHODS AND RESULTS

This investigation was a sub-study analysis conducted in selected cohorts of patients with stable atherosclerotic disease enrolled from a larger prospective, open-label, parallel-group pharmacodynamics (PD) study. We analyzed data from 40 patients treated with either clopidogrel or ticagrelor-based DAPT first, and clopidogrel or ticagrelor-based DPI thereafter. PD measures explored key pathways involved in thrombus formation and included markers of: 1) P2Y12 reactivity, 2) platelet-mediated global thrombogenicity, 3) cyclooxygenase-1 activity, 3) TRAP-induced platelet aggregation; 4) tissue factor (TF)-induced platelet aggregation, and 5) thrombin generation. As compared to DAPT, on a background of the same P2Y12 inhibitor (clopidogrel or ticagrelor), DPI was associated with reduced thrombin generation, increased markers of cyclooxygenase-1 activity and TRAP-induced platelet aggregation and no differences in markers of P2Y12 signaling, platelet-mediated global thrombogenicity and TF-induced platelet aggregation. In an analysis according to P2Y12 inhibitor type, ticagrelor reduced markers of platelet-mediated global thrombogenicity, P2Y12 signaling and rates of high platelet reactivity compared to clopidogrel.

CONCLUSIONS

Compared to DAPT with aspirin and a P2Y12 inhibitor, the use of a P2Y12 inhibitor in adjunct to a vascular dose of rivaroxaban as part of a DPI strategy is associated with similar effects on platelet-mediated global thrombogenicity but reduced thrombin generation. A DPI strategy with ticagrelor is associated with enhanced antithrombotic efficacy, the clinical implications of which warrant larger scale investigations.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03718429.

Antiplatelet Therapy in Patients Undergoing Elective Percutaneous Coronary Intervention

PURPOSE OF REVIEW

The evidence for use of dual antiplatelet therapy (DAPT) for patients undergoing percutaneous coronary intervention (PCI) in the elective setting is relatively sparse and is based on data from more than two decades ago. We will review the evidence supporting the use of DAPT with focus on stable patients undergoing elective PCI, including the role of potent P₂Y₁₂ inhibitors, modified DAPT durations, and more recently, aspirin discontinuation.

RECENT FINDINGS

Clopidogrel is the recommended P₂Y₁₂ inhibitor in the elective PCI setting. The benefit of more potent P₂Y₁₂ inhibitors such as ticagrelor or prasugrel in stable patients is unproven, but their use might be reasonable in those with high clinical or angiographic features of increased ischemic risk without increased risk of bleeding. Moreover, extending DAPT beyond 12 months is associated with a reduction in ischemic events but also increased bleeding. In contrast, shortening DAPT (3-6 months) reduces bleeding compared with 1 year of treatment, but it is also probably associated with increased ischemic events, mainly in higher-risk patients undergoing complex PCI. Recently, early aspirin discontinuation at 3 months (and perhaps as early as 1 month) following PCI reduces bleeding, with no evidence to suggest an increase in ischemic events. Clopidogrel is the P₂Y₁₂ inhibitor of choice, while more data are required to support the use of more potent P₂Y₁₂ inhibitors in stable patients. The duration of DAPT should be tailored to individual patient ischemic and bleeding risks. New strategies, such as early aspirin discontinuation, are promising to reduce bleeding risk without increase in ischemic risk.

Thrombotic Risk and Cardiovascular Events in Patients With Revascularization Deferral After Fractional Flow Reserve Assessment

OBJECTIVES

The aim of this study was to evaluate the impact of thrombotic risk on the occurrence of cardiovascular events in patients with coronary artery disease with deferred revascularization after fractional flow reserve (FFR) measurements.

BACKGROUND

Deferral of revascularization on the basis of FFR is generally considered to be safe, but after deferral, some patients have cardiovascular events over time.

METHODS

From J-CONFIRM registry (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry), 1,263 patients with deferral of revascularization on the basis of FFR were evaluated. The association between thrombotic risk as assessed by CREDO-Kyoto (Coronary Revascularization Demonstrating Outcome Study in Kyoto) thrombotic score and 5-year target vessel failure (TVF) and major adverse cardiac and cerebrovascular events (MACCE) was investigated.

RESULTS

FFR and high thrombotic risk (HTR) were associated with increased risk for 5-year TVF (FFR per 0.01-unit decrease: HR: 1.08; 95% CI: 1.05-1.11; P < 0.001; HTR: HR: 2.16; 95% CI: 1.37-3.39; P < 0.001) and MACCE (FFR per 0.01-unit decrease: HR: 1.05; 95% CI: 1.02-1.06; P < 0.001; HTR: HR: 2.11; 95% CI: 1.56-2.84; P = 0.001). Patients with HTR had higher risk for 5-year TVF (HR: 2.30; 95% CI: 1.45-3.66; P < 0.001) and MACCE (HR: 2.34; 95% CI: 1.75-3.13; P < 0.001) than those without HTR, even when they had negative FFR.

CONCLUSIONS

Assessment of thrombotic risk provides additional prognostic value to FFR in predicting 5-year TVF and MACCE in patients with deferral of revascularization after FFR measurements. (Long-Term Outcomes of Japanese Patients With Deferral of Coronary Intervention Based on Fractional Flow Reserve in Multicenter Registry; UMIN000014473).

Maintained P2Y12 inhibitor monotherapy after shorter-duration of dual antiplatelet therapy in patients undergoing coronary drug-eluting stents implantation: An updated meta-analysis of randomized trials

WHAT IS KNOWN AND OBJECTIVE

It is well known that high in-stent thrombotic risk due to the superimposition of a platelet-rich thrombus was considered as the main origin of major adverse cardiac events after stent implantation. The clinical management of antiplatelet therapy strategy after percutaneous coronary intervention (PCI) remains controversial. This study is sought to explore the efficacy and safety of a maintained P2Y₁₂ inhibitor monotherapy after shorter-duration of dual antiplatelet therapy (DAPT) in these patients.

METHODS

Medline, Google Scholar, Web of Science, and the Cochrane Controlled Trials Registry were searched online for retrieving eligible citations. A composite of all-cause death, myocardial infarction (MI) and stroke was defined as major adverse cardio- and cerebro-vascular events (MACCE), which is analysed as the primary efficacy endpoint. The risk of bleeding events was chosen as safety endpoint.

RESULTS

Five randomized clinical trials (RCT) with 32,143 patients were finally analysed. A maintained P2Y₁₂ inhibitor monotherapy after shorter-duration of DAPT cloud not only reduce the incidence of MACCE [odds ratios (OR): 0.89, 95% confidence intervals (CI): 0.79-0.99, p = 0.037], but also the bleeding risk (OR 0.61, 95% CI: 0.44-0.85, p = 0.003). No higher incidence of any ischaemic events, including MI, stroke or definite stent thrombosis (ST) was observed with respect to this new antiplatelet therapy option.

CONCLUSIONS

A maintained P2Y₁₂ inhibitor monotherapy after shorter-duration of DAPT was suggested as a more preferable antiplatelet therapy option in patients undergoing coronary drug-eluting stents (DES) placement. Larger and more powerful randomized trials with precise sub-analyses are still necessary for further confirming these relevant benefits.

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).

Bleeding avoidance strategies in percutaneous coronary intervention

For many years, bleeding has been perceived as an unavoidable consequence of strategies aimed at reducing thrombotic complications in patients undergoing percutaneous coronary intervention (PCI). However, the paradigm has now shifted towards bleeding being recognized as a prognostically unfavourable event to the same extent as having a new or recurrent ischaemic or thrombotic complication. As such, in parallel with progress in device and drug development for PCI, there is clinical interest in developing strategies that maximize not only the efficacy but also the safety (for example, by minimizing bleeding) of any antithrombotic treatment or procedural aspect before, during or after PCI. In this Review, we discuss contemporary data and aspects of bleeding avoidance strategies in PCI, including risk stratification, timing of revascularization, pretreatment with antiplatelet agents, selection of vascular access, choice of coronary stents and antithrombotic treatment regimens.

Pharmacodynamic profiles of dual-pathway inhibition with or without clopidogrel vs dual antiplatelet therapy in patients with atherosclerotic disease

AIM

Inhibition of thrombin-mediated signaling processes using a vascular dose of rivaroxaban in adjunct to antiplatelet therapy, known as dual-pathway inhibition (DPI), reduces atherothrombotic events in patients with stable atherosclerotic disease. However, there are limited data on the pharmacodynamic (PD) effects of this strategy.

METHODS AND RESULTS

This investigation was conducted in selected cohorts of patients (n=40) with stable atherosclerotic disease enrolled within a larger prospective PD study who were treated with either aspirin plus clopidogrel (DAPT), aspirin plus rivaroxaban 2.5 mg/bid (DPI) or DAPT plus rivaroxaban 2.5 mg/bid. Multiple PD assays assessing of markers of thrombosis were used. PD endpoints included platelet-mediated global thrombogenicity measured by light transmittance aggregometry (LTA) following stimuli with CATF [collagen-related peptide +adenosine diphosphate (ADP) +tissue factor (TF)], markers of P2Y12 reactivity, markers of platelet aggregation using LTA following several stimuli (arachidonic acid, ADP, collagen, TF, and TRAP), thrombin generation and thrombus formation. There was no difference in platelet-mediated global thrombogenicity between groups. Rivaroxaban significantly reduced thrombin generation and was associated with a trend towards reduced TF-induced platelet aggregation. Clopidogrel-based treatments reduced markers of P2Y12 signaling and TRAP-induced platelet aggregation. There were no differences between groups on markers of cyclooxygenase-1 mediated activity.

CONCLUSIONS

Compared with DAPT, DPI does not result in any differences in platelet-mediated global thrombogenicity, but reduces thrombin generation. These PD observations support that modulating thrombin generation by means of factor Xa inhibition in adjunct to antiplatelet therapy provides effective antithrombotic effects, supporting the efficacy and safety findings of DPI observed in clinical.

Appraising the contemporary role of aspirin for primary and secondary prevention of atherosclerotic cardiovascular events

INTRODUCTION

Although the role of aspirin for primary prevention of atherosclerotic cardiovascular disease (ASCVD) has been disputed, its use in secondary ASCVD prevention is well established. Recent trials of primary prevention do not suggest a significant net benefit with aspirin, whereas accruing evidence supports adopting aspirin-free strategies in the context of potent P2Y₁₂ inhibition for the secondary prevention of selected patients undergoing percutaneous coronary intervention.

AREAS COVERED

This updated review aims at summarizing and appraising the pharmacological characteristics and the contemporary role of aspirin for the primary and secondary prevention of ASCVD.

EXPERT OPINION

Recent trials and metanalyses in the context of primary prevention highlighted a modest reduction in ischemic events with aspirin use, counterbalanced by a significant increase in bleeding events. However, ongoing studies on cancer prevention could modify the current paradigm of the unfavorable benefit-risk ratio of aspirin in patients with no overt ASCVD. Conversely, aspirin use is crucial for secondary ASCVD prevention, both in chronic and acute coronary syndromes. Nevertheless, after a brief period of dual antiplatelet therapy, patients at high bleeding risk may benefit from discontinuation of aspirin if a P2Y₁₂ inhibitor is used, hence reducing the bleeding risk with no rebound in thrombotic events.

Clopidogrel monotherapy in patients with and without on-treatment high platelet reactivity: a SMART-CHOICE substudy

BACKGROUND

Although P2Y12 inhibitor monotherapy has emerged as a promising alternative for dual antiplatelet therapy (DAPT), there remains concern regarding the safety of clopidogrel monotherapy.

AIMS

We sought to investigate clinical outcomes of clopidogrel monotherapy in patients with and without on-treatment high platelet reactivity (HPR).

METHODS

In the SMART-CHOICE study, three-month DAPT followed by P2Y12 inhibitor monotherapy was compared with 12-month DAPT in patients undergoing percutaneous coronary intervention. A platelet function test was performed for 833 patients with clopidogrel-based therapy. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE: a composite of all-cause death, myocardial infarction, or stroke) at 12 months.

RESULTS

Overall, 108 (13.0%) patients had HPR on clopidogrel. Patients with HPR had a significantly higher rate of MACCE than patients without HPR (8.7% vs 1.5%, adjusted HR 3.036, 95% CI: 1.060-8.693, p=0.038). The treatment effect of clopidogrel monotherapy for the 12-month MACCE was not significantly different compared with DAPT among patients with HPR (8.0% vs 9.4%, adjusted HR 0.718, 95% CI: 0.189-2.737, p=0.628) and without HPR (2.2% vs 0.9%, adjusted HR 2.587, 95% CI: 0.684-9.779, p=0.161; adjusted p for interaction=0.170).

CONCLUSIONS

Clopidogrel monotherapy showed treatment effects comparable to DAPT for MACCE in patients with or without HPR. However, HPR was significantly associated with an increased risk of MACCE in clopidogrel-treated patients regardless of maintenance of aspirin.

CLINICAL TRIAL REGISTRATION

Comparison Between P2Y12 Antagonist Monotherapy and Dual Antiplatelet Therapy After DES (SMART-CHOICE) (ClinicalTrials.gov: NCT02079194).

Ticagrelor monotherapy in patients at high bleeding risk undergoing percutaneous coronary intervention: TWILIGHT-HBR

AIMS

Patients at high bleeding risk (HBR) represent a prevalent subgroup among those undergoing percutaneous coronary intervention (PCI). Early aspirin discontinuation after a short course of dual antiplatelet therapy (DAPT) has emerged as a bleeding avoidance strategy. The aim of this study was to assess the effects of ticagrelor monotherapy after 3-month DAPT in a contemporary HBR population.

METHODS AND RESULTS

This prespecified analysis of the TWILIGHT trial evaluated the treatment effects of early aspirin withdrawal followed by ticagrelor monotherapy in HBR patients undergoing PCI with drug-eluting stents. After 3 months of ticagrelor plus aspirin, event-free patients were randomized to 12 months of aspirin or placebo in addition to ticagrelor. A total of 1064 (17.2%) met the Academic Research Consortium definition for HBR. Ticagrelor monotherapy reduced the incidence of the primary endpoint of Bleeding Academic Research Consortium (BARC) 2, 3, or 5 bleeding compared with ticagrelor plus aspirin in HBR (6.3% vs. 11.4%; hazard ratio (HR) 0.53, 95% confidence interval (CI) 0.35-0.82) and non-HBR patients (3.5% vs. 5.9%; HR 0.59, 95% CI 0.46-0.77) with similar relative (Pinteraction = 0.67) but a trend towards greater absolute risk reduction in the former [-5.1% vs. -2.3%; difference in absolute risk differences (ARDs) -2.8%, 95% CI -6.4% to 0.8%, P = 0.130]. A similar pattern was observed for more severe BARC 3 or 5 bleeding with a larger absolute risk reduction in HBR patients (-3.5% vs. -0.5%; difference in ARDs -3.0%, 95% CI -5.2% to -0.8%, P = 0.008). There was no significant difference in the key secondary endpoint of death, myocardial infarction, or stroke between treatment arms, irrespective of HBR status.

CONCLUSIONS

Among HBR patients undergoing PCI who completed 3-month DAPT without experiencing major adverse events, aspirin discontinuation followed by ticagrelor monotherapy significantly reduced bleeding without increasing ischaemic events, compared with ticagrelor plus aspirin. The absolute risk reduction in major bleeding was larger in HBR than non-HBR patients.

Cardiovascular medicine: a year in review

Cardiovascular medicine is facing several challenges in the current era, dominated by the rapid spread of a previously unknown virus around the world. Indeed, the 2020 COVID-19 pandemic set the course of cardiovascular science and education in an extraordinary way, hogging the attention of the medical community. Notably, while COVID-19 impacted research progress, there has been considerable effort in exploring topics of great interest, from the management of acute coronary syndromes to new horizons in the treatment of heart failure, from novelties in the surgical treatment of cardiovascular disease to new data on implantable cardiac devices, and from new diagnostic applications of multimodal imaging techniques to relevant basic science findings. Minerva Cardiology and Angiology, formerly Minerva Cardioangiologica, has strived to inform its readers on these topics and novelties, aiming for a succinct yet poignant melding of timeliness and accuracy. Accordingly, the purpose of this narrative review is to highlight and summarize the major research and review articles published during 2020. In particular, we provide a broad overview of the novelties identifying six major areas of interest in the field of cardiovascular sciences in which new evidences have contributed to improving prevention, diagnosis and treatment of heart and vessels diseases.

Simplified Academic Research Consortium for High Bleeding Risk (ARC-HBR) Definition Predicts Bleeding Events in Patients With Heart Failure

BACKGROUND

It has recently been reported that the simplified Academic Research Consortium for High Bleeding Risk (ARC-HBR) definition, which excludes 6 rare criteria, is comparable to the original ARC-HBR definition in predicting major bleeding in patients with coronary artery disease (CAD) who undergo percutaneous coronary intervention. In this study, we investigated whether the simplified ARC-HBR definition could be applied to patients with heart failure (HF) to identify those at high bleeding risk (HBR).Methods and Results:In all, 2,437 patients hospitalized for HF were enrolled in this study. Patients were divided into 2 groups based on the simplified ARC-HBR definition: those at HBR (n=2,026; 83.1%) and those not (non-HBR group; n=411; 16.9%). The HBR group was older (72.0 vs. 61.0 years; P<0.001) and had a lower prevalence of CAD (31.1% vs. 36.5%; P=0.034) than the non-HBR group. Kaplan-Meier analysis showed that post-discharge bleeding events defined as hemorrhagic stroke or gastrointestinal bleeding were more frequent in the HBR than non-HBR group (log-rank P<0.001). The simplified ARC-HBR definition accurately predicted bleeding events (Fine-Gray model; hazard ratio 2.777, 95% confidence interval 1.464-5.270, P=0.001).

CONCLUSIONS

The simplified ARC-HBR definition predicts a high risk of bleeding events in patients with HF.

Reflections after TWILIGHT study: a new era in secondary prevention without aspirin?

Dual antiplatelet therapy (DAPT) is mandatory in patients undergoing percutaneous coronary interventions (PCIs), but carries an increased bleeding risk which must be weighed over the expected antithrombotic benefit. In recent years, DAPT optimization strategy has been enriched by the concept of early withdrawal of aspirin ('aspirin-free' strategy). This strategy is supported by the modern advancements in pharmacological and procedural fields (i.e. the availability of P2Y12 receptor inhibitors with a concomitant 'aspirin-like' effect), the advocated use of pharmacological non-antiplatelet secondary prevention strategies (i.e. angiotensin-converting enzyme inhibitor, statins, beta-blockers), the use of modern stents and the increasingly widespread use of intra-coronary imaging techniques. In the last few years, five clinical trials (GLOBAL LEADERS, TWILIGHT, STOP-DAPT2, SMART CHOICE, TICO) and their own meta-analysis have been followed, aiming to evaluate the efficacy and safety of different 'aspirin-free' strategies. They showed that aspirin withdrawal (1-3 months after PCI), determines a consistent reduction of bleeding risk, without compromising efficacy endpoints. It resulted in a class IIa indication in the 2020 European Society of Cardiology Guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation, which suggested the early withdrawal of aspirin in patients undergoing PCI and considered to be at low ischaemic and low bleeding risk, or at high bleeding risk.

Efficacy and Safety of Aspirin for Primary Cardiovascular Risk Prevention in Younger and Older Age: An Updated Systematic Review and Meta-analysis of 178,310 Subjects from 21 Randomized Studies

AIMS

 The efficacy and safety of aspirin for primary cardiovascular disease (CVD) prevention is controversial. The aim of this study was to investigate the efficacy and safety of aspirin in subjects with no overt CVD, with a focus on age as a treatment modifier.

METHODS AND RESULTS

 Randomized trials comparing aspirin use versus no aspirin use or placebo were included. The primary efficacy outcome was all-cause death. The primary safety outcome was major bleeding. Secondary ischemic and bleeding outcomes were explored. Subgroup analyses were conducted to investigate the consistency of the effect sizes in studies including younger and older individuals, using a cut-off of 65 years. A total of 21 randomized trials including 173,810 individuals at a mean follow-up of 5.3 years were included. Compared with control, aspirin did not reduce significantly the risk of all-cause death (risk ratio: 0.96; 95% confidence interval: 0.92-1.00, p = 0.057). Major adverse cardiovascular events were significantly reduced by 11%, paralleled by significant reductions in myocardial infarction and transient ischemic attack. Major bleeding, intracranial hemorrhage, and gastrointestinal bleeding were significantly increased by aspirin. There was a significant age interaction for death (p for interaction = 0.007), with aspirin showing a statistically significant 7% relative benefit on all-cause death in studies including younger patients.

CONCLUSION

 The use of aspirin in subjects with no overt CVD was associated with a neutral effect on all-cause death and a modest lower risk of major cardiovascular events at the price of an increased risk in major bleeding. The benefit of aspirin might be more pronounced in younger individuals.

Efficacy and Safety of Ticagrelor Monotherapy by Clinical Presentation: Pre-Specified Analysis of the GLOBAL LEADERS Trial

Background

The optimal duration of dual antiplatelet therapy after coronary drug‐eluting stent placement in adults with stable coronary artery disease (SCAD) versus acute coronary syndromes (ACS) remains uncertain.

Methods and Results

This was a prespecified subgroup analysis of the GLOBAL LEADERS trial. Participants were randomly assigned 1:1 to the experimental or reference strategy, stratified by ACS (experimental, n=3750; reference, n=3737) versus SCAD (experimental, n=4230; reference, n=4251). The experimental strategy was 75 to 100 mg aspirin daily plus 90 mg ticagrelor twice daily for 1 month, followed by 23 months of ticagrelor monotherapy. The reference strategy was 75 to 100 mg aspirin daily plus either 75 mg clopidogrel daily (for SCAD) or 90 mg ticagrelor twice daily (for ACS) for 12 months, followed by aspirin monotherapy for 12 months. The primary end point at 2 years was a composite of all‐cause mortality or non‐fatal centrally adjudicated new Q‐wave myocardial infarction. The key secondary safety end point was site‐reported Bleeding Academic Research Consortium grade 3 or 5 bleeding. The primary end point occurred in 147 (3.92%) versus 169 (4.52%) patients with ACS (rate ratio [RR], 0.86; 95% CI, 0.69–1.08; P=0.189), and in 157 (3.71%) versus 180 (4.23%) patients with SCAD (RR, 0.87; 95% CI, 0.71–1.08; P=0.221) with experimental and reference strategy, respectively (P‐interaction=0.926). Bleeding Academic Research Consortium grade 3 or 5 bleeding occurred in 73 (1.95%) versus 100 (2.68%) patients with ACS (RR, 0.73; 95% CI, 0.54–0.98; P=0.037), and in 90 (2.13%) versus 69 (1.62%) patients with SCAD (RR, 1.32; 95% CI, 0.97–1.81; P=0.081; P‐interaction=0.007).

Conclusions

While there was no evidence for differences in efficacy between treatment strategies by subgroup, the experimental strategy appeared to reduce bleeding risk in patients with ACS but not in patients with SCAD.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01813435.

3- or 1-Month DAPT in Patients at High Bleeding Risk Undergoing Everolimus-Eluting Stent Implantation

OBJECTIVES

The aim of this study was to evaluate 2 abbreviated dual-antiplatelet therapy (DAPT) regimens in patients at high bleeding risk (HBR) undergoing percutaneous coronary intervention (PCI).

BACKGROUND

Current-generation drug-eluting stents are preferred over bare-metal stents for HBR patients, but their optimal DAPT management remains unknown.

METHODS

The XIENCE Short DAPT program included 3 prospective, multicenter, single-arm studies enrolling HBR patients who underwent successful PCI with a cobalt-chromium everolimus-eluting stent. After 1 month (XIENCE 28 USA and XIENCE 28 Global) or 3 months (XIENCE 90) of DAPT, event-free patients discontinued the P2Y₁₂ inhibitor. The postmarketing approval XIENCE V USA study was used as historical control in a propensity score-stratified analysis.

RESULTS

A total of 3,652 patients were enrolled. The propensity-adjusted rate of the primary endpoint of all-cause mortality or myocardial infarction was 5.4% among 1,693 patients on 3-month DAPT versus 5.4% in the 12-month DAPT historical control (P_{noninferiority} = 0.0063) and 3.5% among 1,392 patients on 1-month DAPT versus 4.3% in the 6-month DAPT historical control (P_{noninferiority} = 0.0005). Bleeding Academic Research Consortium (BARC) types 2 to 5 bleeding was not significantly lower with 3- or 1-month DAPT, while BARC types 3 to 5 bleeding was reduced in both experimental groups. The rate of definite or probable stent thrombosis was 0.2% in XIENCE 90 (P < 0.0001 for the performance goal of 1.2%) and 0.3% in XIENCE 28.

CONCLUSIONS

Among HBR patients undergoing PCI with cobalt-chromium everolimus-eluting stents, DAPT for 1 or 3 months was noninferior to 6 or 12 months of DAPT for ischemic outcomes and may be associated with less major bleeding and a low incidence of stent thrombosis.

Genetic testing in patients undergoing percutaneous coronary intervention: rationale, evidence and practical recommendations

INTRODUCTION

Clopidogrel is the most frequently utilized P2Y12 inhibitor and is characterized by broad interindividual response variability resulting in impaired platelet inhibition and increased risk of thrombotic complications in a considerable number of patients. The potent P2Y12 inhibitors, prasugrel and ticagrelor, can overcome this limitation but at the expense of an increased risk of bleeding. Genetic variations of the cytochrome P450 (CYP) 2 C19 enzyme, a key determinant in clopidogrel metabolism, have been strongly associated with clopidogrel response profiles prompting investigations of genetic-guided selection of antiplatelet therapy.

AREAS COVERED

The present manuscript focuses on the rationale for the use of genetic testing to guide the selection of platelet P2Y12 inhibitors among patients undergoing percutaneous coronary intervention (PCI). Moreover, a comprehensive appraisal of the available evidence and practical recommendations is provided.

EXPERT COMMENTARY

Implementation of genetic testing as a strategy to guide the selection of therapy can result in escalation (i.e. switching to prasugrel or ticagrelor) or de-escalation (i.e. switching to clopidogrel) of P2Y12 inhibiting therapy. Most recent investigations support the clinical benefit of a genetic guided selection of antiplatelet therapy in patients undergo PCI. Integrating the results of genetic testing with clinical and procedural variables represents a promising strategy for a precision medicine approach for the selection of antiplatelet therapy among patients undergoing PCI.

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.

Antithrombotic Therapy After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) is a treatment option for symptomatic patients with severe aortic stenosis who are candidates for a bioprosthesis across the entire spectrum of risk. However, TAVR carries a risk for thrombotic and bleeding events, underscoring the importance of defining the optimal adjuvant antithrombotic regimen. Antithrombotic considerations are convoluted by the fact that many patients undergoing TAVR are generally elderly and present with multiple comorbidities, including conditions that may require long-term oral anticoagulation (OAC) (eg, atrial fibrillation) and antiplatelet therapy (eg, coronary artery disease). After TAVR among patients without baseline indications for OAC, recent data suggest dual-antiplatelet therapy to be associated with an increased risk for bleeding events, particularly early postprocedure, compared with single-antiplatelet therapy with aspirin. Concerns surrounding the potential for thrombotic complications have raised the hypothesis of adjunctive use of OAC for patients with no baseline indications for anticoagulation. Although effective in modulating thrombus formation at the valve level, the bleeding hazard has shown to be unacceptably high, and the net benefit of combining antiplatelet and OAC therapy is unproven. For patients with indications for the use of long-term OAC, such as those with atrial fibrillation, the adjunctive use of antiplatelet therapy increases bleeding. Whether direct oral anticoagulant agents achieve better outcomes than vitamin K antagonists remains under investigation. Overall, single-antiplatelet therapy and OAC appear to be reasonable strategies in patients without and with indications for concurrent anticoagulation. The aim of the present review is to appraise the current published research and recommendations surrounding the management of antithrombotic therapy after TAVR, with perspectives on evolving paradigms and ongoing trials.