P2Y12 Inhibitor or Aspirin Monotherapy for Secondary Prevention of Coronary Events

Should We Use Aspirin or P2Y12 Inhibitor Monotherapy in Stable Ischemic Heart Disease?

PURPOSE OF REVIEW

To summarize the recent evidence and guideline recommendations on aspirin or P2Y12 inhibitor monotherapy in patients with stable ischemic heart disease and provide insights into future directions on this topic, which involves transition to a personalized assessment of bleeding and thrombotic risks.

RECENT FINDINGS

It has been questioned whether the evidence for aspirin as the foundational component of secondary prevention in patients with coronary artery disease aligns with contemporary pharmaco-invasive strategies. The recent HOST-EXAM study randomized patients who had received dual antiplatelet therapy for 6 to 18 months without ischemic or major bleeding events to either clopidogrel or aspirin for a further 24 months, and demonstrated that the patients in the clopidogrel arm had significantly lower rates of both thrombotic and bleeding complications compared to those in the aspirin arm. The patient-level PANTHER meta-analysis showed that in patients with established coronary artery disease, P2Y12 inhibitor monotherapy was associated with lower rates of myocardial infarction, stent thrombosis as well as gastrointestinal bleeding and hemorrhagic stroke compared to aspirin monotherapy, albeit with similar rates of all-cause mortality, cardiovascular mortality and major bleeding. Long-term low-dose aspirin is recommended for secondary prevention in patients with stable ischemic heart disease, with clopidogrel monotherapy being acknowledged as a feasible alternative. Dual antiplatelet therapy for six months after percutaneous coronary intervention remains the standard recommendation for patients with stable ischemic heart disease. However, the duration of dual antiplatelet therapy may be shortened and followed by P2Y12 inhibitor monotherapy or prolonged based on individualized evaluation of the patient's risk profile.

Antithrombotic Strategies for Patients With Peripheral Artery Disease: JACC Scientific Statement

Patients with peripheral artery disease (PAD) experience major cardiovascular and limb events. Antithrombotic strategies including antiplatelets and anticoagulants remain a cornerstone of treatment and prevention. Recent trials have shown heterogeneity in the response to antithrombotic therapies in patients presenting primarily with PAD when compared to those presenting primarily with coronary artery disease. In addition, there is observed heterogeneity with regards to the effects of antiplatelets and anticoagulants with respect to different outcomes including cardiovascular and major adverse limb events. This, coupled with risks of bleeding, requires a patient-centered and holistic assessment of benefit-risk when selecting antithrombotic strategies for patients with PAD. A global multidisciplinary work group was convened to evaluate antithrombotic strategies in PAD and to summarize the current state of the art. Common clinical scenarios around antithrombotic decision making were provided. Finally, insights with regard to implementation future investigation were described.

Clopidogrel Versus Aspirin as Monotherapy Following Dual Antiplatelet Therapy in Patients With Acute Coronary Syndrome Receiving a Drug-Eluting Stent: A Systematic Literature Review and Meta-Analysis

OBJECTIVE

This study aimed to evaluate the comparative effectiveness and safety of clopidogrel versus aspirin as monotherapy following adequate dual antiplatelet therapy (DAPT) in patients with acute coronary syndrome (ACS).

METHODS

MEDLINE, Embase, and CENTRAL were searched from database inception to September 1, 2023. Randomized controlled trials (RCTs) and observational studies evaluating the effectiveness or safety of clopidogrel versus aspirin as monotherapy following DAPT in patients with ACS who received a drug-eluting stent were included. Random-effects meta-analyses were conducted to compare risks of major adverse cardiovascular events (MACE) and clinically relevant bleeding.

RESULTS

Of 6242 abstracts identified, three unique studies were included: one RCT and two retrospective cohort studies. Studies included a total of 7081 post-percutaneous coronary intervention ACS patients, 4260 of whom received aspirin monotherapy and 2821 received clopidogrel monotherapy. Studies included variable proportions of patients with ST-elevation myocardial infarction (STEMI), non-STEMI, and unstable angina. From the meta-analysis, clopidogrel was associated with a 28% reduction in the risk of MACE compared with aspirin (hazard ratio [HR]: 0.72; 95% confidence interval [CI]: 0.54, 0.98), with no significant difference in clinically relevant bleeding (HR: 0.92; 95% CI: 0.68, 1.24).

CONCLUSION

Despite the paucity of published evidence on the effectiveness and safety of clopidogrel versus aspirin in patients with ACS post-drug-eluting stent implantation, this meta-analysis suggests that clopidogrel versus aspirin may result in a lower risk of MACE, with a similar risk of major bleeding. The present results are hypothesis-generating and further large RCTs comparing antiplatelet monotherapy options in ACS patients are warranted.

Aspirin: latest evidence and developments

Aspirin is a foundation drug of the pharmaceutical industry originally derived as an analgesic/anti-inflammatory agent but serendipitously discovered to have use as a prophylactic drug for major adverse cardiovascular events (MACE). Its modern-day utility in this latter role relies on its efficacy/safety balance in a contemporary population where, at least in high-income countries, age-standardised incident rates for MACE are falling, and where there are now competing therapeutic agents. Its future may be determined by its potential role as a chemoprophylactic or adjunct agent for cancer or other disease states. It therefore will continue to be the subject of further clinical research.

Optimizing antithrombotic therapy in patients with coexisting cardiovascular and gastrointestinal disease

Balancing the safety and efficacy of antithrombotic agents in patients with gastrointestinal disorders is challenging because of the potential for interference with the absorption of antithrombotic drugs and for an increased risk of bleeding. In this Review, we address considerations for enteral antithrombotic therapy in patients with cardiovascular disease and gastrointestinal comorbidities. For those with gastrointestinal bleeding (GIB), we summarize a general scheme for risk stratification and clinical evidence on risk reduction approaches, such as limiting the use of concomitant medications that increase the risk of GIB and the potential utility of gastrointestinal protection strategies (such as proton pump inhibitors or histamine type 2 receptor antagonists). Furthermore, we summarize the best available evidence and potential gaps in our knowledge on tailoring antithrombotic therapy in patients with active or recent GIB and in those at high risk of GIB but without active or recent GIB. Finally, we review the recommendations provided by major medical societies, highlighting the crucial role of teamwork and multidisciplinary discussions to customize the antithrombotic regimen in patients with coexisting cardiovascular and gastrointestinal diseases.

The impact of platelets on the metastatic potential of tumour cells

In cancer, activation of platelets by tumor cells is critical to disease progression. Development of precise antiplatelet targeting may improve outcomes from anticancer therapy. Alongside a distinct shift in functionality such as pro-metastatic and pro-coagulant properties, platelet production is often accelerated significantly early in carcinogenesis and the cancer-associated thrombocytosis increases the risk of metastasis formation and thromboembolic events. Tumor-activated platelets facilitate the proliferation of migrating tumor cells and shield them from immune surveillance and physical stress during circulation. Additionally, platelet-tumor cell interactions promote tumor cell intravasation, intravascular arrest, and extravasation through a repertoire of adhesion molecules, growth factors and angiogenic factors. Particularly, the presence of circulating tumor cell (CTC) clusters in association with platelets is a negative prognostic indicator. The contribution of platelets to the metastatic process is an area of intense investigation and this review provides an overview of the advances in understanding platelet-tumor cell interactions and their contribution to disease progression. Also, we review the potential of targeting platelets to interfere with the metastatic process.

Low-dose aspirin for the prevention of atherosclerotic cardiovascular disease

During the past 30 years, several developments have occurred in the antiplatelet field, including the role of aspirin in primary prevention of atherosclerotic cardiovascular disease. There have been several attempts to develop antiplatelet drugs more effective and safer than aspirin and a shift in emphasis from efficacy to safety, advocating aspirin-free antiplatelet regimens after percutaneous coronary intervention. Evidence supporting a chemopreventive effect of low-dose aspirin against colorectal (and other digestive tract) cancer has also strengthened. The aim of this article is to revisit the role of aspirin in the prevention of atherothrombosis across the cardiovascular risk continuum, in view of developments in the antiplatelet field. The review will offer a clinical perspective on aspirin's mechanism of action, pharmacokinetics, and pharmacodynamics. This will be followed by a detailed discussion of its clinical efficacy and safety.

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.

Clinical impact of coronary revascularization over medical treatment in chronic coronary syndromes: A systematic review and meta-analysis

OBJECTIVE

To provide a quantitative comparison between myocardial revascularization (REVASC) and optimal medical treatment (OMT) alone in patients with chronic coronary syndrome (CCS).

METHODS

Pertinent studies were searched for in PubMed/Medline until 12/03/2023. Randomized controlled trials that compare REVASC to OMT reporting clinical outcomes were selected according to PRISMA guidelines. The primary outcome was cardiovascular death. Two investigators independently assessed the study quality and extracted data.

RESULTS

Twenty-eight randomized controlled studies (RCTs) including 20692 patients were included in this meta-analysis. The rate of cardiovascular mortality was significantly lower among patients treated with myocardial revascularization [risk ratio (RR) 0.79, 95% CI 0.69-0.90]. Age (p = 0.03), multivessel disease (p < 0.001), and follow-up duration (p = 0.001) were significant moderators of CV mortality. Subgroup analyses showed a larger benefit in patients treated with drug-eluting stents and those without chronic total occlusion. Among secondary outcomes, myocardial infarction was less frequent in the REVASC group (RR = 0.74; p < 0.001), while no significant difference was found for all-cause mortality (p = 0.09) nor stroke (p = 0.26).

CONCLUSIONS

The present analysis showed lower rates of CV mortality and myocardial infarction in CCS patients treated with myocardial revascularization compared to OMT. This benefit was larger with increasing follow-up duration. Personalized treatment based on patient characteristics and lesion complexity may optimize clinical outcomes in patients with CCS.

Integrating platelet reactivity in the age, creatinine and ejection fraction score to predict clinical outcomes following percutaneous coronary intervention in patients with chronic coronary syndrome: the PR-ACEF score

To evaluate if integrating platelet reactivity (PR) evaluation in the original age, creatinine and ejection fraction (ACEF) score could improve the diagnostic accuracy of the model in patients with stable coronary artery disease (CAD). We enrolled patients treated with percutaneous coronary intervention between 2010 and 2011. High PR was included in the model (PR-ACEF). Co-primary end points were a composite of death/myocardial infarction (MI) and major adverse cardiovascular events (MACE). Overall, 471 patients were enrolled. Compared to the ACEF score, the PR-ACEF showed an improved diagnostic accuracy for death/MI (AUC 0.610 vs 0.670, p < 0.001) and MACE (AUC 0.572 vs 0.634, p < 0.001). These findings were confirmed using internal validation with bootstrap resampling. At 5 years, the PR-ACEF value > 1.75 was independently associated with death/MI [HR 3.51, 95% CI (1.97-6.23)] and MACE [HR 2.77, 95% CI (1.69-4.53)]. The PR-ACEF score was effective in improving the diagnostic performance of the ACEF score at the long-term follow-up.

Extended Clopidogrel Monotherapy vs DAPT in Patients With Acute Coronary Syndromes at High Ischemic and Bleeding Risk: The OPT-BIRISK Randomized Clinical Trial

Importance

Purinergic receptor P2Y12 (P2Y12) inhibitor monotherapy after a certain period of dual antiplatelet therapy (DAPT) may be an attractive option of maintenance antiplatelet treatment for patients undergoing percutaneous coronary intervention (PCI) who are at both high bleeding and ischemic risk (birisk).

Objective

To determine if extended P2Y12 inhibitor monotherapy with clopidogrel is superior to ongoing DAPT with aspirin and clopidogrel after 9 to 12 months of DAPT after PCI in birisk patients with acute coronary syndromes (ACS).

Design, Setting, and Participants

This was a multicenter, double-blind, placebo-controlled, randomized clinical trial including birisk patients with ACS who had completed 9 to 12 months of DAPT after drug-eluting stent implantation and were free from adverse events for at least 6 months at 101 China centers between February 2018 and December 2020. Study data were analyzed from April 2023 to May 2023.

Interventions

Patients were randomized either to clopidogrel plus placebo or clopidogrel plus aspirin for an additional 9 months.

Main Outcomes and Measures

The primary end point was Bleeding Academic Research Consortium (BARC) types 2, 3, or 5 bleeding 9 months after randomization. The key secondary end point was major adverse cardiac and cerebral events (MACCE; the composite of all-cause death, myocardial infarction, stroke or clinically driven revascularization). The primary end point was tested for superiority, and the MACCE end point was tested for sequential noninferiority and superiority.

Results

A total of 7758 patients (mean [SD] age, 64.8 [9.0] years; 4575 male [59.0%]) were included in this study. The primary end point of BARC types 2, 3, or 5 bleeding occurred in 95 of 3873 patients (2.5%) assigned to clopidogrel plus placebo and 127 of 3885 patients (3.3%) assigned to clopidogrel plus aspirin (hazard ratio [HR], 0.75; 95% CI, 0.57-0.97; difference, -0.8%; 95% CI, -1.6% to -0.1%; P = .03). The incidence of MACCE was 2.6% (101 of 3873 patients) in the clopidogrel plus placebo group and 3.5% (136 of 3885 patients) in the clopidogrel plus aspirin group (HR, 0.74; 95% CI, 0.57-0.96; difference, -0.9%; 95% CI, -1.7% to -0.1%; P < .001 for noninferiority; P = .02 for superiority).

Conclusions and Relevance

Among birisk patients with ACS who completed 9 to 12 months of DAPT after drug-eluting stent implantation and were free from adverse events for at least 6 months before randomization, an extended 9-month clopidogrel monotherapy regimen was superior to continuing DAPT with clopidogrel in reducing clinically relevant bleeding without increasing ischemic events.

Trial Registration

ClinicalTrials.gov Identifier: NCT03431142.

Antiplatelet therapy for treatment of coronary artery disease in older patients

Coronary artery disease in older patients is more frequently diffuse and complex, and is often treated by percutaneous coronary intervention on top of medical therapy. There are currently no specific recommendations for antiplatelet therapy in patients aged≥75 years. Aspirin remains pivotal, and is still indicated as a long-term treatment after percutaneous coronary intervention. In addition, a P2Y12 inhibitor is administered for 6-12 months according to clinical presentation. Age is a minor bleeding risk factor, but because older patients often have several co-morbidities, they are considered as having a high bleeding risk according to different scoring systems. This increased bleeding risk has resulted in different therapeutic strategies for antithrombotic treatment after percutaneous coronary intervention; these include short dual antiplatelet therapy, a switch from potent to less potent antiplatelet therapy or single antiplatelet therapy with a P2Y12 inhibitor instead of aspirin, among others. A patient-centred approach, taking into account health status, functional ability, frailty, cognitive skills, bleeding and ischaemic risks and patient preference, is essential when caring for older adults with coronary artery disease. The present review focuses on the knowledge base, specificities of antiplatelet therapies, a balance between haemorrhagic and ischaemic risk, strategies for antiplatelet therapy and directions for future investigation pertaining to coronary artery disease in older patients.

One-Month Dual Antiplatelet Therapy Followed by P2Y12 Inhibitor Monotherapy After Biodegradable Polymer Drug-Eluting Stent Implantation - The REIWA Region-Wide Registry

BACKGROUND

The safety and feasibility of using 1-month dual antiplatelet therapy (DAPT) followed by P2Y12inhibitor monotherapy for patients after percutaneous coronary intervention (PCI) with thin-strut biodegradable polymer drug-eluting stents (BP-DES) in daily clinical practice remain uncertain.

METHODS AND RESULTS

The REIWA region-wide registry is a prospective study conducted in 1 PCI center and 9 local hospitals in northern Japan. A total of 1,202 patients who successfully underwent final PCI using BP-DES (Synergy: n=400; Ultimaster: n=401; Orsiro: n=401), were enrolled in the registry, and received 1-month DAPT followed by P2Y12inhibitor (prasugrel 3.75 mg/day or clopidogrel 75 mg/day) monotherapy. The primary endpoint was a composite of cardiovascular and bleeding events at 12 months, including cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST), ischemic or hemorrhagic stroke, and Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding. Based on the results of a previous study, we set the performance goal at 5.0%. Over the 1-year follow-up, the primary endpoint occurred in 3.08% of patients, which was lower than the predefined performance goal (Pnon-inferiority<0.0001). Notably, definite ST occurred in only 1 patient (0.08%) within 1 year (at 258 days). No differences were observed in the primary endpoint between stent types.

CONCLUSIONS

The REIWA region-wide registry suggests that 1-month DAPT followed by P2Y12inhibitor monotherapy is safe and feasible for Japanese patients with BP-DES.

One- versus three-month dual antiplatelet therapy in high bleeding risk patients undergoing percutaneous coronary intervention for non-ST-segment elevation acute coronary syndromes

BACKGROUND

A short dual antiplatelet therapy (DAPT) duration has been proposed for patients at high bleeding risk (HBR) undergoing drug-eluting coronary stent (DES) implantation. Whether this strategy is safe and effective after a non-ST-segment elevation acute coronary syndrome (NSTE-ACS) remains uncertain.

AIMS

We aimed to compare the impact of 1-month versus 3-month DAPT on clinical outcomes after DES implantation among HBR patients with or without NSTE-ACS.

METHODS

This is a prespecified analysis from the XIENCE Short DAPT programme involving three prospective, international, single-arm studies evaluating the safety and efficacy of 1-month (XIENCE 28 USA and Global) or 3-month (XIENCE 90) DAPT among HBR patients after implantation of a cobalt-chromium everolimus-eluting stent. Ischaemic and bleeding outcomes associated with 1- versus 3-month DAPT were assessed according to clinical presentation using propensity score stratification.

RESULTS

Of 3,364 HBR patients (1,392 on 1-month DAPT and 1,972 on 3-month DAPT), 1,164 (34.6%) underwent DES implantation for NSTE-ACS. At 12 months, the risk of the primary endpoint of death or myocardial infarction was similar between 1- and 3-month DAPT in patients with (hazard ratio [HR] 1.09, 95% confidence interval [CI]: 0.71-1.65) and without NSTE-ACS (HR 0.88, 95% CI: 0.63-1.23; p-interaction=0.34). The key secondary endpoint of Bleeding Academic Research Consortium (BARC) Type 2-5 bleeding was consistently reduced in both NSTE-ACS (HR 0.57, 95% CI: 0.37-0.88) and stable patients (HR 0.84, 95% CI: 0.61-1.15; p-interaction=0.15) with 1-month DAPT.

CONCLUSIONS

Among HBR patients undergoing implantation of an everolimus-eluting stent, 1-month, compared to 3-month DAPT, was associated with similar ischaemic risk and reduced bleeding at 1 year, irrespective of clinical presentation.

Injury minimization after myocardial infarction: focus on extracellular vesicles

Despite improvements in clinical outcomes following acute myocardial infarction, mortality remains high, especially in patients with severely reduced left ventricular ejection fraction (LVEF <30%), emphasizing the need for effective cardioprotective strategies adjunctive to recanalization. Traditional cell therapy has shown equivocal success, shifting the focus to innovative cardioactive biologicals and cell mimetic therapies, particularly extracellular vesicles (EVs). EVs, as carriers of non-coding RNAs and other essential biomolecules, influence neighbouring and remote cell function in a paracrine manner. Compared to cell therapy, EVs possess several clinically advantageous traits, including stability, ease of storage (enabling off-the-shelf clinical readiness), and decreased immunogenicity. Allogeneic EVs from mesenchymal and/or cardiac stromal progenitor cells demonstrate safety and potential efficacy in preclinical settings. This review delves into the translational potential of EV-based therapeutic approaches, specifically highlighting findings from large-animal studies, and offers a synopsis of ongoing early-stage clinical trials in this domain.

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.

Monotherapy with P2Y12-inhibitors after dual antiplatelet therapy: Filling gaps in evidence

BACKGROUND

Whether P2Y12 inhibitor monotherapy (P2Y12-I) is superior to aspirin following DAPT discontinuation post-PCI remains to be established.

METHODS

We updated our prior network meta-analysis where P2Y12-I and aspirin had been compared with DAPT or directly with each other. The focus is specifically on the available direct evidence, now consisting of the three head-to-head comparisons of P2Y12-I and aspirin in event-free PCI patients after DAPT. We include a Trial Sequential Analysis of the direct evidence based on meta-analytical literature.

RESULTS

The main finding reveals a 39% significantly lower risk of myocardial infarction with P2Y12-I (RR 0.61, 95% CI 0.47-0.78, p = 0.0001, I2 = 0%) with no difference in bleeding. Trial Sequential Analysis demonstrates clinically meaningful evidence for a reduction in the incidence of myocardial infarction with P2Y12-I that is also supported by statistical significance.

CONCLUSIONS

Accruing data highlight that P2Y12-I following DAPT discontinuation after PCI is associated with lower risk for MI and a similar risk for bleeding as compared with ASA. In light of potential limitations to the widespread adoption of life-long P2Y12-I treatment, clinicians should consider identifying selected patients who are expected to derive the highest benefit.

Antiplatelet De-Escalation Strategies in Patients Undergoing Percutaneous Coronary Intervention

Dual antiplatelet therapy-the combination of aspirin and a P2Y12 inhibitor-remains the standard antiplatelet regimen recommended to prevent ischemic complications immediately after percutaneous coronary intervention. Nonetheless, recent advances in stent technologies, percutaneous coronary intervention techniques, adjunctive pharmacotherapy for secondary prevention, and the rising awareness of the prognostic impact of bleeding, which are inevitably associated with dual antiplatelet therapy, led to the investigation of alternative antiplatelet regimens related to fewer bleeding and a preserved ischemic protection. Thrombotic complications occur mostly in the first months after percutaneous coronary intervention, while the risk of bleeding remains stable over time; this observation laid the foundation of the concept of antiplatelet de-escalation, consisting of a more intense antiplatelet regimen early after percutaneous coronary intervention, followed by a less potent antiplatelet therapy thereafter. According to new definitions proposed by the Academic Research Consortium, de-escalation can be achieved by discontinuation of 1 antiplatelet agent, switching from a potent P2Y12 inhibitor to clopidogrel, or by reducing the dose of antiplatelet agents. This review discusses the rationale and the evidence supporting antiplatelet de-escalation, provides practical guidance to use these new regimens, and gives insights into future developments in the field.

Systemic immune-inflammation index as a novel predictor of major adverse cardiovascular events in patients undergoing percutaneous coronary intervention: a meta-analysis of cohort studies

BACKGROUND

The Systemic Immune-Inflammation Index (SII), a novel marker of inflammation based on neutrophil, platelet, and lymphocyte counts, has demonstrated potential prognostic value in patients undergoing percutaneous coronary intervention (PCI). Our aim was to assess the correlation between the SII and major adverse cardiovascular events following percutaneous coronary intervention.

METHODS

We searched PubMed, Web of Science, Embase, and The Cochrane Library from inception to November 20, 2023, for cohort studies investigating the association between SII and the occurrence of MACEs after PCI. Statistical analysis was performed using Revman 5.3, with risk ratios (RRs) and 95% confidence intervals (CIs) as relevant parameters.

RESULTS

In our analysis, we incorporated a total of 8 studies involving 11,117 participants. Our findings revealed that a high SII is independently linked to a increased risk of MACEs in PCI patients (RR: 2.08,95%CI: 1.87-2.32, I2 = 42%, p < 0.00001). Additionally, we demonstrated the prognostic value of SII in all-cause mortality, heart failure, and non-fatal myocardial infarction.

CONCLUSIONS

Elevated SII may serve as a potential predictor for subsequent occurrence of MACEs in patients undergoing PCI.

TRIAL REGISTRATION

Our protocol was registered in PROSPERO (registration number: CRD42024499676).

Controversy in cardiology: clopidogrel or acetylsalicylic acid in the treatment of chronic coronary syndromes?

Secondary prevention of patients with chronic coronary syndrome is based on the long-term use of a single anti-aggregating drug which is traditionally represented by acetylsalicylic acid (ASA) in light of the results of studies and meta-analyses which have demonstrated a clear anti-ischaemic efficacy against of an acceptable increase in the risk of bleeding, especially intracranial and gastrointestinal bleeding. The availability of drugs such as clopidogrel, which inhibits platelet activity through the P2Y12 receptor pathway, has called into question this paradigm, also in consideration of the fact that the scientific evidence that supports the use of ASA in secondary prevention is based on dated studies with some limitations. Over the last few years, randomized trials have demonstrated how clopidogrel has an efficacy profile comparable to that of ASA and a safety profile that is sometimes even better. In light of the new evidence, it is therefore legitimate to ask whether in this clinical scenario, ASA should still be considered the drug of choice or whether clopidogrel could represent the preferable alternative.

Smoking and outcomes following personalized antiplatelet therapy in chronic coronary syndrome patients: A substudy from the randomized PATH-PCI trial

BACKGROUND

This is a sub-analysis of the Personalized Antithrombotic Therapy for Coronary Heart Disease after PCI (PATH-PCI) trial in China to explore the relationship between smoking and outcomes following personalized antiplatelet therapy (PAT) in chronic coronary syndrome (CCS) patients undergoing percutaneous coronary intervention (PCI).

METHODS

As a single-center, prospective, randomized controlled and open-label trial, the PATH-PCI trial randomized CCS patients undergoing PCI into standard group or personalized group guided by a novel platelet function test (PFT), from December 2016 to February 2018. All patients were divided into smokers and nonsmokers according to their smoking status. Subsequently, we underwent a 180-day follow-up evaluation. The primary endpoint was the net adverse clinical events (NACE).

RESULTS

Regardless of smoking status, in the incidence of NACE, there was a reduction with PAT but that the reductions are not statistically significant. In the incidence of bleeding events, we found no statistically significant difference between two groups (smokers: 2.0% vs. 1.4%, HR = 1.455, 95% confidence interval [CI]: 0.595-3.559, p = .412; nonsmokers: 2.2% vs. 1.8%, HR = 1.228, 95% CI: 0.530-2.842, p = .632). In smokers, PAT reduced major adverse cardiac and cerebrovascular events (MACCE) by 48.7% (3.0% vs. 5.9%, HR = 0.513, 95% CI: 0.290-0.908, p = .022), compared with standard antiplatelet therapy (SAT). PAT also reduced the major adverse cardiovascular events (MACE) but there was no statistically difference in the reductions (p > .05). In nonsmokers, PAT reduced MACCE and MACE by 51.5% (3.3% vs. 6.7%, HR = 0.485, 95% CI: 0.277-0.849, p = .011) and 63.5% (1.8% vs. 4.9%, HR = 0.365, 95% CI: 0.178-0.752, p = .006), respectively. When testing p-values for interaction, we found there was no significant interaction of smoking status with treatment effects of PAT (pint-NACE  = .184, pint-bleeding  = .660).

CONCLUSION

Regardless of smoking, PAT reduced the MACE and MACCE, with no significant difference in bleeding. This suggests that PAT was an recommendable regimen to CCS patients after PCI, taking into consideration both ischemic and bleeding risk.

The CNIC-polypill (acetylsalicylic acid, atorvastatin, and ramipril), an effective and cost-saving secondary prevention strategy compared with other therapeutic options in patients with ischaemic heart disease

Aims

The retrospective NEPTUNO study evaluated the effectiveness of the Centro Nacional de Investigaciones Cardiovasculares (CNIC)-polypill (including acetylsalicylic acid, ramipril, and atorvastatin) vs. other therapeutic approaches in secondary prevention for cardiovascular (CV) disease. In this substudy, the focus was on the subgroup of patients with ischaemic heart disease (IHD).

Methods and results

Patients on four strategies: CNIC-polypill, its monocomponents as loose medications, equipotent medications, and other therapies. The primary endpoint was the incidence of recurrent major adverse CV events (MACEs) after 2 years. After matching, 1080 patients were included in each cohort. The CNIC-polypill cohort had a significantly lower incidence of recurrent MACE compared with monocomponents, equipotent drugs, and other therapies cohorts (16.1 vs. 24, 24.4, and 24.3%, respectively; P < 0.001). The hazard ratios (HRs) for recurrent MACE were higher in monocomponents (HR = 1.12; P = 0.042), equipotent drugs (HR = 1.14; P = 0.031), and other therapies cohorts (HR = 1.17; P = 0.016) compared with the CNIC-polypill, with a number needed to treat of 12 patients to prevent a MACE. The CNIC-polypill demonstrated a greater reduction in LDL cholesterol (LDL-c; -56.1 vs. -43.6, -33.3, and -33.2% in the monocomponents, equipotent drugs, and other therapies, respectively; P < 0.001) and systolic blood pressure (-13.7 vs. -11.5, -10.6, and -9.1% in the CNIC-polypill, monocomponents, equipotent drugs, and other therapies, respectively; P < 0.001) compared with other cohorts. The CNIC-polypill intervention was less costly and more effective than any other therapeutic option, with €2317-€2407 cost savings per event prevented.

Conclusion

In IHD, the CNIC-polypill exemplifies a guideline-recommended secondary prevention treatment linked to better outcomes and cost saving compared with other therapeutic options.

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.

Antithrombotic therapy in patients with acute coronary syndrome: similarities and differences between a European expert consensus document and the 2023 European Society of Cardiology guidelines

Antithrombotic therapy represents the cornerstone of the pharmacological treatment in patients with acute coronary syndrome (ACS). The optimal combination and duration of antithrombotic therapy is still matter of debate requiring a critical assessment of patient comorbidities, clinical presentation, revascularization modality, and/or optimization of medical treatment. The 2023 European Society of Cardiology (ESC) guidelines for the management of patients with ACS encompassing both patients with and without ST segment elevation ACS have been recently published. Shortly before, a European expert consensus task force produced guidance for clinicians on the management of antithrombotic therapy in patients with ACS as well as chronic coronary syndrome. The scope of this manuscript is to provide a critical appraisal of differences and similarities between the European consensus paper and the latest ESC recommendations on oral antithrombotic regimens in ACS patients.

Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology 2023 Focused Update of the Guidelines for the Use of Antiplatelet Therapy

Antiplatelet therapy (APT) is the foundation of treatment and prevention of atherothrombotic events in patients with atherosclerotic cardiovascular disease. Selecting the optimal APT strategies to reduce major adverse cardiovascular events, while balancing bleeding risk, requires ongoing review of clinical trials. Appended, the focused update of the Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology guidelines for the use of APT provides recommendations on the following topics: (1) use of acetylsalicylic acid in primary prevention of atherosclerotic cardiovascular disease; (2) dual APT (DAPT) duration after percutaneous coronary intervention (PCI) in patients at high bleeding risk; (3) potent DAPT (P2Y12 inhibitor) choice in patients who present with an acute coronary syndrome (ACS) and possible DAPT de-escalation strategies after PCI; (4) choice and duration of DAPT in ACS patients who are medically treated without revascularization; (5) pretreatment with DAPT (P2Y12 inhibitor) before elective or nonelective coronary angiography; (6) perioperative and longer-term APT management in patients who require coronary artery bypass grafting surgery; and (7) use of APT in patients with atrial fibrillation who require oral anticoagulation after PCI or medically managed ACS. These recommendations are all on the basis of systematic reviews and meta-analyses conducted as part of the development of these guidelines, provided in the Supplementary Material.

Effect of ticagrelor versus clopidogrel after implantation of drug-eluting stents guided by either intravascular ultrasound or angiography in patients with acute coronary syndrome-propensity score matching analysis

BACKGROUND

The effect of different dual antiplatelet therapies on thrombotic events on the background of intravascular ultrasound (IVUS) guidance is unclear. We investigated whether ticagrelor can provide any additional benefit to clopidogrel in reducing thrombotic events in acute coronary syndrome (ACS) treated with drug- eluting stent (DES), when guided by IVUS or not.

METHODS

A total of 5,666 ACS patients who underwent DES implantation and who were discharged on dual antiplatelet therapy were enrolled and grouped according to the use of IVUS or not. Each group was subdivided into two subgroups according to the type of P2Y12 inhibitor used after discharge. Propensity score matching (PSM) was used between the IVUS and no-IVUS groups. Covariate adjustment of Cox proportional hazards model was used between the ticagrelor and clopidogrel groups. Thrombotic event at 12 months was compared in groups separately.

RESULTS

After PSM, 12-month follow-up data were available for 1,174 patients. Major adverse cardiac events (MACE) were less frequent in the IVUS-guided group (2.2% vs. 4.3%, P = 0.081) with a trend toward statistical significance. Comparison of antiplatelet regimens revealed significantly fewer major adverse cardiac and cerebrovascular events (MACCE) with ticagrelor in the entire PSM cohort and angiography-guided subgroup (2.9% vs. 5.7%, P = 0.035; 3.1% vs. 6.4%, P = 0.020, respectively). Among patients in the IVUS-guided group the outcome was comparable (2.5% vs. 4.4%, P = 0.312). Ticagrelor was associated with increasing bleeding incidence in the entire PSM cohort (1.3% vs. 3.3%, P = 0.030), mainly due to Bleeding Academic Research Consortium type 2 bleeding (0.7% vs. 2.6%, P = 0.010). The results were consistent after covariate adjustment of Cox proportional hazards model.

CONCLUSION

The comparison of ischemic benefit between ticagrelor and clopidogrel was similar in patients receiving IVUS guidance during stent implantation, probably due to the precise implantation of IVUS. Multicenter, randomized studies should be performed to validate this conclusion.

Clopidogrel vs Aspirin Monotherapy Beyond 1 Year After Percutaneous Coronary Intervention

BACKGROUND

It remains unclear whether clopidogrel is better suited than aspirin as the long-term antiplatelet monotherapy following dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI).

OBJECTIVES

This study compared clopidogrel monotherapy following 1 month of DAPT (clopidogrel group) with aspirin monotherapy following 12 months of DAPT (aspirin group) after PCI for 5 years.

METHODS

STOPDAPT-2 (Short and Optimal Duration of Dual Antiplatelet Therapy 2) is a multicenter, open-label, adjudicator-blinded, randomized clinical trial conducted in Japan. Patients who underwent PCI with cobalt-chromium everolimus-eluting stents were randomized in a 1-to-1 fashion either to clopidogrel or aspirin groups. The primary endpoint was a composite of cardiovascular outcomes (cardiovascular death, myocardial infarction, stroke, or definite stent thrombosis) or major bleeding (TIMI major or minor bleeding).

RESULTS

Among 3,005 study patients (age: 68.6 ± 10.7 years; women: 22.3%; acute coronary syndrome: 38.3%), 2,934 patients (97.6%) completed the 5-year follow-up (adherence to the study drugs at 395 days: 84.7% and 75.9%). The clopidogrel group compared with the aspirin group was noninferior but not superior for the primary endpoint (11.75% and 13.57%, respectively; HR: 0.85; 95% CI: 0.70-1.05; Pnoninferiority < 0.001; Psuperiority = 0.13), whereas it was superior for the cardiovascular outcomes (8.61% and 11.05%, respectively; HR: 0.77; 95% CI: 0.61-0.97; P = 0.03) and not superior for major bleeding (4.44% and 4.92%, respectively; HR: 0.89; 95% CI: 0.64-1.25; P = 0.51). By the 1-year landmark analysis, clopidogrel was numerically, but not significantly, superior to aspirin for cardiovascular events (6.79% and 8.68%, respectively; HR: 0.77; 95% CI: 0.59-1.01; P = 0.06) without difference in major bleeding (3.99% and 3.32%, respectively; HR: 1.23; 95% CI: 0.84-1.81; P = 0.31).

CONCLUSIONS

Clopidogrel might be an attractive alternative to aspirin with a borderline ischemic benefit beyond 1 year after PCI.

Impact of Age on Antiplatelet Monotherapy in the Chronic Maintenance Period After Percutaneous Coronary Intervention: A Post Hoc Analysis From the HOST-EXAM Extended Study

BACKGROUNDS

The HOST-EXAM Extended study reported the benefit of clopidogrel monotherapy over aspirin monotherapy in secondary prevention after percutaneous coronary intervention (PCI). This age-specific subgroup analysis of the study aimed to assess the impact of age on antiplatelet monotherapy after PCI.

METHODS

We analysed data from the per-protocol population (4717 patients) with a median follow-up of 5.8 years. The old age group comprised 2033 patients (43.1%), defined as those 65 years of age or older. The primary end point was the composite of all-cause death, nonfatal myocardial infarction, stroke, readmission due to acute coronary syndrome (ACS), and Bleeding Academic Research Consortium (BARC) bleeding type 3 or greater. The secondary end points were thrombotic composite outcomes and any bleeding.

RESULTS

Age correlated with an elevated risk of adverse events, particularly from age 65. Clopidogrel monotherapy was associated with a reduction of the primary end point in both the old age group (19.4% vs 23.1%, hazard ratio [HR] 0.802, 95% confidence interval [CI] 0.664-0.968; P = 0.022) and the young age group (7.8% vs 11.7%, HR 0.646, 95% CI 0.506-0.825; P < 0.001), without significant interaction (interaction P = 0.167). These findings were consistent for the secondary composite thrombotic end point and any bleeding events (interaction P value of secondary thrombotic end point: 0.786; interaction P value of any bleeding end point: 0.565). Consistent results were observed in analyses with a 75-year age cutoff and in subgroup analyses by 10-year age intervals.

CONCLUSIONS

In patients requiring antiplatelet monotherapy after PCI, occurrence of both ischemic and bleeding events dramatically increased from age 65. The beneficial impact of clopidogrel over aspirin monotherapy was consistent regardless of age.

CLINICAL TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT02044250.

Antiplatelet therapy guided by CYP2C19 point-of-care pharmacogenetics plus multidimensional treatment decisions

Aim: Implementation of CYP2C19 point-of-care (POC) pharmacogenetic (PGx) testing with personalized treatment recommendations. Methods: POC CYP2C19 genotyping plus expert evaluation of risk factors for ischemic and bleeding events. Results: 167 patients underwent PGx testing, 54 (32.3%) were CYP2C19 loss of function carriers, and POC versus standard PGx analysis results for *2 and *3 variants matched in 100%. Antiplatelet therapy was adjusted in 44 patients (26.3%), but always required consideration of patient-specific factors. Conclusion: CYP2C19 POC-PGx is reliable and offers clinically relevant advantages for immediate evidence-based adaptations of antiplatelet therapy, whereas in less acute cases conventional PGx testing can also have advantages. Antiplatelet therapy has become more complex, and implementation of PGx-based personalized antiplatelet therapy requires complementary expert knowledge.

Balancing Benefits and Risks of Oral Antiplatelet Strategies in patients With Coronary Artery Diseases: An Evolving Issue

Identifying the most appropriate antiplatelet therapy for each patient to prevent ischemic events while minimizing the risk of bleeding is an integral part of the short- and long-term management of patients with coronary artery disease (CAD). This review aims to summarize the available evidence on the contemporary use of P2Y12 inhibitors in CAD patients, focusing on strategies aimed at providing adequate ischemic protection while preventing bleeding risk through dual antiplatelet therapy (DAPT) modulation. Randomized trials and observational studies have been reviewed to determine the most appropriate antiplatelet treatment for CAD patients with different risk profiles. Both ischemic and bleeding events have a significant prognostic impact and should be carefully considered in clinical decision-making. Current guidelines recommend the use of third-generation PY2Y12 inhibitors (prasugrel or ticagrelor) over clopidogrel, as a part of DAPT, in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention. Newer P2Y12 inhibitors have a more rapid onset of action and less interindividual variability in platelet inhibition than clopidogrel but are associated with an increased risk of bleeding that may limit their benefit. Importantly, the anti-ischemic benefit of ticagrelor and prasugrel is mainly observed in the first weeks after ACS, whereas clopidogrel seems to provide the best balance between ischemic protection and bleeding as long-term maintenance therapy. These concepts support DAPT modulation after the acute phase, by de-escalating from full-dose to low-dose newer P2Y12 inhibitors, by switching to clopidogrel, or by early withdrawing aspirin to maximize both the efficacy and safety of antiplatelet therapy in patients with CAD.

Individualization of Duration of Dual Antiplatelet Therapy after Coronary Stenting: A Comprehensive, Evidence-Based Review

Dual antiplatelet therapy (DAPT), comprising aspirin and a P2Y12 receptor inhibitor, is the cornerstone of post-percutaneous coronary intervention treatment to prevent stent thrombosis and reduce the risk of adverse cardiovascular events. The selection of an optimal DAPT regimen, considering the interplay of various antiplatelet agents, patient profiles, and procedural characteristics, remains an evolving challenge. Traditionally, a standard duration of 12 months has been recommended for DAPT in most patients. While contemporary guidelines provide general frameworks, DAPT modulation with longer or shorter treatment courses followed by aspirin or P2Y12 inhibitor monotherapy are evolving towards an individualized strategy to optimize the balance between efficacy and safety. This review comprehensively examines the current landscape of DAPT strategies after coronary stenting, with a focus on emerging evidence for treatment individualization.