Dual antiplatelet therapy de-escalation in acute coronary syndrome: an individual patient meta-analysis

De-escalation of antithrombotic treatment after acute coronary syndrome, a new paradigm

After an acute coronary syndrome (ACS) it is imperative to balance the bleeding vs. the ischemic risk given the similar prognostic impact of the two events. Since the post-discharge bleeding risk is substantially stable over time whereas the ischemic risk accumulates in the first weeks to months, a strategy of de-escalation of antithrombotic treatment, consisting in the reduction of either the duration (i.e., early interruption of one antiplatelet agent) or the intensity (i.e., switching from the more potent P2Y12-inhibitors prasugrel or ticagrelor to clopidogrel) of dual antiplatelet therapy (DAPT), has been proposed. Reducing the intensity of DAPT can be carried out as a default strategy (unguided approach) or based on the results of either platelet function tests or genetic tests (guided approach). Overall, all de-escalation strategies have shown to consistently decrease bleeding events with no apparent increase in ischemic events as compared to 12-month standard-of-care DAPT. Owing however to several limitations and weaknesses of the available evidence, de-escalation strategies are currently not recommended as a routine, but should rather be considered for selected ACS patients, such as those at increased risk of bleeding.

Ticagrelor monotherapy in ST-elevation myocardial infarction: An individual patient-level meta-analysis from TICO and T-PASS trials

BACKGROUND

Patients with ST-elevation myocardial infarction (STEMI) tend to be excluded or under-represented in randomized clinical trials evaluating the effects of potent P2Y12 inhibitor monotherapy after short-term dual antiplatelet therapy (DAPT).

METHODS

Individual patient data were pooled from randomized clinical trials that included STEMI patients undergoing drug-eluting stent (DES) implantation and compared ticagrelor monotherapy after short-term (≤3 months) DAPT versus ticagrelor-based 12-month DAPT in terms of centrally adjudicated clinical outcomes. The co-primary outcomes were efficacy outcome (composite of all-cause death, myocardial infarction, or stroke) and safety outcome (Bleeding Academic Research Consortium type 3 or 5 bleeding) at 1 year.

FINDINGS

The pooled cohort contained 2,253 patients with STEMI. The incidence of the primary efficacy outcome did not differ between the ticagrelor monotherapy group and the ticagrelor-based DAPT group (1.8% versus 2.0%; hazard ratio [HR] = 0.88; 95% confidence interval [CI] = 0.49-1.61; p = 0.684). There was no difference in cardiac death between the groups (0.6% versus 0.7%; HR = 0.89; 95% CI = 0.32-2.46; p = 0.822). The incidence of the primary safety outcome was significantly lower in the ticagrelor monotherapy group (2.3% versus 4.0%; HR = 0.56; 95% CI = 0.35-0.92; p = 0.020). No heterogeneity of treatment effects was observed for the primary outcomes across subgroups.

CONCLUSIONS

In patients with STEMI treated with DES implantation, ticagrelor monotherapy after short-term DAPT was associated with lower major bleeding without an increase in the risk of ischemic events compared with ticagrelor-based 12-month DAPT. Further research is necessary to extend these findings to non-Asian patients.

FUNDING

This study was funded by Biotronik (Bülach, Switzerland).

Long-term outcomes of high bleeding risk patients undergoing percutaneous coronary intervention: a Korean nationwide registry

BACKGROUND AND AIMS

Patients with high bleeding risk (HBR) undergoing percutaneous coronary intervention (PCI) are at increased risk of not only bleeding, but also ischaemic events. This study aimed to determine the long-term relative risk of ischaemic and bleeding events in HBR patients.

METHODS

This study was a nationwide cohort study, based on the Korean National Health Insurance Review and Assessment Service database. Patients diagnosed with stable angina or acute coronary syndrome and those who underwent PCI in Korea between 2009 and 2018 were included in the analysis. According to the Academic Research Consortium HBR criteria, the total population was divided into HBR and non-HBR groups. The co-primary outcomes were major bleeding events and ischaemic (composite of cardiac death, myocardial infarction, and ischaemic stroke) events.

RESULTS

Among a total of 325 417 patients who underwent PCI, 66 426 patients (20.4%) had HBR. During the follow-up period, HBR patients had a higher risk for major bleeding events (23.9% vs. 8.9%, P < .001) and ischaemic events (33.8% vs. 14.4%, P < .001). However, the impact of HBR was significant for major bleeding events [hazard ratio (HR) 3.12, 95% confidence interval (CI) 3.04-3.21, P < .001] and for ischaemic events (HR 2.50, 95% CI 2.45-2.56, P < .001). The HBR group was also associated with a greater risk of all-cause mortality (HR 3.73, 95% CI 3.66-3.79, P < .001). The average annual rate of major bleeding events within the first year after PCI was 5.5% for a single major criterion, and 2.9% for a single minor criterion.

CONCLUSIONS

Among patients undergoing PCI, those with HBR were at increased long-term risk for both bleeding and ischaemic events, with a greater risk of mortality compared to non-HBR patients.

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.

The Evolving Field of Acute Coronary Syndrome Management: A Critical Appraisal of the 2023 European Society of Cardiology Guidelines for the Management of Acute Coronary Syndrome

Acute coronary syndromes (ACS), encompassing conditions like ST-elevation myocardial infarction (STEMI) and non-ST-elevation acute coronary syndromes (NSTE-ACS), represent a significant challenge in cardiovascular care due to their complex pathophysiology and substantial impact on morbidity and mortality. The 2023 European Society of Cardiology (ESC) guidelines for ACS management introduce several updates in key areas such as invasive treatment timing in NSTE-ACS, pre-treatment strategies, approaches to multivessel disease, and the use of imaging modalities including computed tomography (CT) coronary angiography, magnetic resonance imaging (MRI), and intracoronary imaging techniques, such as optical coherence tomography (OCT) and intravascular ultrasound (IVUS). They also address a modulation of antiplatelet therapy, taking into consideration different patient risk profiles, and introduce new recommendations for low-dose colchicine. These guidelines provide important evidence-based updates in practice, reflecting an evolution in the understanding and management of ACS, yet some potentially missed opportunities for more personalized care and technology adoption are discussed.

Impact of ethnicity on antiplatelet treatment regimens for bleeding reduction in acute coronary syndromes: a systematic review and pre-specified subgroup meta-analysis

AIMS

Randomized controlled trials (RCTs) testing bleeding reduction strategies using antiplatelet treatment regimens (BRATs) in acute coronary syndromes (ACS) have shown promising results, but the generalizability of these findings may be significantly influenced by the ethnicity of the patients enrolled, given that East Asian (EA) patients show different ischaemic-bleeding risk profile compared to non-EA patients.

METHODS AND RESULTS

RCTs comparing a BRAT vs. standard 12-month dual antiplatelet therapy (DAPT) in patients with ACS undergoing percutaneous coronary intervention (PCI) were selected. The primary efficacy endpoint was major adverse cardiovascular events (MACE) as defined in each trial and the primary safety endpoint was minor or major bleeding. Twenty-six RCTs testing seven different BRATs were included. The only strategy associated with a trade-off in MACE was 'upfront unguided de-escalation' in the subgroup of non-EAs (risk ratio 1.16, 95% confidence interval 1.09-1.24). All but aspirin monotherapy-based strategies (i.e. 'short and very short DAPT followed by aspirin') were associated with reduced bleeding compared with standard DAPT in both EA and non-EA patients. There were no significant differences between subgroups, but the lack of RCTs in some of the included strategies and the difference in the certainty of evidence between EA and non-EA patients revealed that the evidence in support of different BRATs in ACS undergoing PCI is influenced by ethnicity. Moreover, absolute risk reduction estimation revealed that some BRATs might be more effective than others in reducing bleeding according to ethnicity.

CONCLUSION

The majority of BRATs are associated with reduced bleeding without any trade-off in hard ischaemic endpoints regardless of ethnicity. However, the supporting evidence and relative safety profiles of different BRATs might be significantly affected by ethnicity, which should be taken into account in clinical practice.

STUDY REGISTRATION

This study is registered in PROSPERO (CRD42023416710).

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.

De-escalation from ticagrelor to clopidogrel in patients with acute myocardial infarction: the TALOS-AMI HBR substudy

BACKGROUND

The benefits of de-escalation of P2Y12 inhibition after percutaneous coronary intervention (PCI) may differ by high bleeding risk (HBR) status.

AIMS

We investigated the efficacy and safety of de-escalation from ticagrelor to clopidogrel after PCI by HBR status.

METHODS

This is a non-prespecified post hoc analysis of the TicAgrelor Versus CLOpidogrel in Stabilized Patients with Acute Myocardial Infarction (TALOS-AMI) trial. Net adverse clinical events (a composite of cardiovascular death, myocardial infarction, stroke, or Bleeding Academic Research Consortium [BARC] bleeding type 2, 3, or 5) at 1 year post-PCI were compared between the de-escalation (clopidogrel plus aspirin) and the active control (ticagrelor plus aspirin) groups by HBR status, as defined by the modification of the Academic Research Consortium (ARC) criteria.

RESULTS

A total of 2,625 patients in the TALOS-AMI trial were analysed. Of these, 589 (22.4%) met the modified ARC-HBR criteria. The de-escalation group had lower primary endpoint rates than the control group in both HBR (hazard ratio [HR] 0.47, 95% confidence interval [CI]: 0.26-0.84) and non-HBR (HR 0.59, 95% CI: 0.41-0.84) patients. There were no differences in treatment effect for the primary endpoint regardless of HBR status (p for interaction=0.904). BARC bleeding type 3 or 5 was less common in the de-escalation than the control group among HBR patients only (HR 0.24, 95% CI: 0.07-0.84).

CONCLUSIONS

In stabilised acute myocardial infarction patients, unguided de-escalation from ticagrelor to clopidogrel was associated with a lower rate of net adverse clinical outcomes irrespective of HBR status. The effect of de-escalation of P2Y12 inhibition on reducing haemorrhagic events was greater in patients with HBR.

De-escalation or abbreviation of dual antiplatelet therapy in acute coronary syndromes and percutaneous coronary intervention: a Consensus Statement from an international expert panel on coronary thrombosis

Conventional dual antiplatelet therapy (DAPT) for patients with acute coronary syndromes undergoing percutaneous coronary intervention comprises aspirin with a potent P2Y purinoceptor 12 (P2Y12) inhibitor (prasugrel or ticagrelor) for 12 months. Although this approach reduces ischaemic risk, patients are exposed to a substantial risk of bleeding. Strategies to reduce bleeding include de-escalation of DAPT intensity (downgrading from potent P2Y12 inhibitor at conventional doses to either clopidogrel or reduced-dose prasugrel) or abbreviation of DAPT duration. Either strategy requires assessment of the ischaemic and bleeding risks of each individual. De-escalation of DAPT intensity can reduce bleeding without increasing ischaemic events and can be guided by platelet function testing or genotyping. Abbreviation of DAPT duration after 1-6 months, followed by monotherapy with aspirin or a P2Y12 inhibitor, reduces bleeding without an increase in ischaemic events in patients at high bleeding risk, particularly those without high ischaemic risk. However, these two strategies have not yet been compared in a head-to-head clinical trial. In this Consensus Statement, we summarize the evidence base for these treatment approaches, provide guidance on the assessment of ischaemic and bleeding risks, and provide consensus statements from an international panel of experts to help clinicians to optimize these DAPT approaches for individual patients to improve outcomes.

Association of ADP-Induced Whole-Blood Platelet Aggregation with Serum Low-Density Lipoprotein Cholesterol in Patients with Coronary Artery Disease When Receiving Maintenance Ticagrelor-Based Dual Antiplatelet Therapy

The degree of platelet inhibition in patients undergoing dual antiplatelet therapy (DAPT) affects cardiovascular outcomes after acute coronary syndromes (ACS) and/or percutaneous coronary intervention. Our aim was to search for correlates of residual ex vivo platelet reactivity and circulating soluble P-selectin (sP-selectin), an index of in vivo platelet activation, in patients being treated by DAPT with ticagrelor. Adenosine diphosphate (ADP)-induced platelet aggregability (by multiple electrode aggregometry) and plasma sP-selectin were estimated in 62 stable post-ACS subjects (46 men and 16 women; mean age: 64 ± 10 years; 30 with type 2 diabetes (T2DM)) undergoing maintenance DAPT with ticagrelor and aspirin. These patients did not exhibit heart failure or other relevant coexistent diseases except for properly controlled T2DM, mild renal insufficiency, and hypertension. We also assessed this in 64 subjects on clopidogrel-based DAPT matched for age, sex, and T2DM status. ADP-induced platelet aggregation was below the optimal levels (190-460 arbitrary units (AU) * min) in most patients receiving ticagrelor-based DAPT, especially in those with below-median (<1.9 mmol/L) serum concentrations of low-density lipoprotein cholesterol (LDL-c) (128 ± 61 vs. 167 ± 73 AU * min for below-median and above-median LDL-c, respectively, p = 0.025). In contrast, platelet reactivity did not differ by LDL-c on clopidogrel-based DAPT (246 ± 101 vs. 268 ± 108 AU * min for below-median and above-median LDL-c, respectively, p > 0.4). Plasma sP-selectin was found to be unrelated to serum LDL-c when receiving DAPT with ticagrelor (p > 0.4) or clopidogrel (p > 0.8). In conclusion, our preliminary observational study suggests the association of lower residual ex vivo platelet aggregability with better LDL-c control in patients undergoing ticagrelor-based maintenance DAPT, which does not appear to be reflected by plasma sP-selectin. Whether the serum LDL-c level should be considered among the factors affecting the degree of platelet inhibition for those treated with ticagrelor-based DAPT needs to be investigated in larger studies.

De-escalation strategies in patients with acute coronary syndrome: a step towards precision medicine

INTRODUCTION

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y₁₂ inhibitor is a cornerstone in the treatment of patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). Current international guidelines recommend the use of 12 months of DAPT with newer P2Y₁₂ inhibitors (i.e. ticagrelor or prasugrel) as first-line therapy in this setting. However, intense and prolonged DAPT regimens are associated with an increased risk of bleeding, with relevant prognostic implications. Recently, a strategy of de-escalation of P2Y₁₂ inhibitors has been proposed as an alternative to conventional DAPT to mitigate the risk of bleeding while preserving ischemic protection after ACS.

AREAS COVERED

In this review, we summarize the available evidence on guided and unguided strategies for P2Y₁₂ inhibitor de-escalation in patients with ACS undergoing PCI.

EXPERT OPINION

Among patients with ACS, guided and unguided de-escalation strategies are safe and effective for secondary cardiovascular prevention. Although the implementation of genetic and platelet function tests is of interest for treatment personalization, the routine use of guided de-escalation strategies seems impractical. In this context, unguided de-escalation approaches appear more attractive, convenient, and suitable for contemporary practice.