Aspirin-Free Prasugrel Monotherapy Following Coronary Artery Stenting in Patients With Stable CAD

Uninterrupted direct-acting oral anticoagulation in patients undergoing transradial percutaneous coronary procedures: The DOAC-NOSTOP study rationale and design

BACKGROUND

patients with atrial fibrillation (AF) under treatment with chronic oral anticoagulation (OAC) often require coronary angiography with or without percutaneous coronary intervention (PCI). Deciding the management of OAC during this periprocedural period requires balancing the risks of hemorrhage and thrombotic complications. Guidelines recommend an uninterrupted strategy in patients receiving Vitamin-K Antagonists (VKA). However, for patients undergoing coronary angiography or PCI while on direct oral anticoagulants (DOACs), withdrawal 12-24 h prior to the procedure is still recommended. This is based on expert opinions given the lack of evidence. Therefore, whether DOAC discontinuation prior to trans-radial coronary procedures should be the strategy of choice is a matter of debate and solid evidence is needed to guide clinical decision making.

METHODS

The DOAC-NOSTOP study is a prospective, single-arm, open-label study evaluating the safety of DOACs continuation in 200 patients undergoing transradial percutaneous coronary procedures. DOAC treatment will not be interrupted throughout the periprocedural period. Primary outcome will be Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 events, assessed at a 30-day follow-up.

CONCLUSIONS

The DOAC-NOSTOP is the first study prospectively assessing the risk of bleeding with uninterrupted DOAC in patients undergoing trans-radial percutaneous coronary procedures.

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.

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.

Geographic disparity of pathophysiological coronary artery disease characteristics: Insights from ASET trials

BACKGROUND

The geographical disparity in the pathophysiological pattern of coronary artery disease (CAD) among patients undergoing percutaneous coronary intervention (PCI) is unknown.

OBJECTIVES

To elucidate the geographical variance in the pathophysiological characteristics of CAD.

METHODS

Physiological indices derived from angiography-based fractional flow reserve pullbacks from patients with chronic coronary syndrome enrolled in the ASET Japan (n = 206) and ASET Brazil (n = 201) studies, which shared the same eligibility criteria, were analysed. The pathophysiological patterns of CAD were characterised using Murray law-based quantitative flow ratio (μQFR)-derived indices acquired from pre-PCI angiograms. The diffuseness of CAD was defined by the μQFR pullback pressure gradient index.

RESULTS

Significant functional stenoses pre-PCI (μQFR ≤0.80) were more frequent in ASET Japan compared to ASET Brazil (89.9% vs. 67.5%, p < 0.001), as were rates of a post-PCI μQFR <0.91 (22.1% vs. 12.9%, p = 0.013). In the multivariable analysis, pre-procedural μQFR and diffuse disease were independent factors for predicting a post-PCI μQFR <0.91, which contributed to the different rates of post-PCI μQFR ≥0.91 between the studies. Among vessels with a post-PCI μQFR <0.91, a consistent diffuse pattern of CAD pre- and post-PCI occurred in 78.3% and 76.7% of patients in ASET Japan and Brazil, respectively; only 6.3% (Japan) and 10.0% (Brazil) of vessels had a major residual gradient. Independent risk factors for diffuse disease were diabetes mellitus in ASET Japan, and age and male gender in Brazil.

CONCLUSIONS

There was geographic disparity in pre-procedural angiography-based pathophysiological characteristics. The combined pre-procedural physiological assessment of vessel μQFR and diffuseness of CAD may potentially identify patients who will benefit most from PCI.

Prasugrel Monotherapy After Percutaneous Coronary Intervention for Chronic Coronary Syndrome: Insights From ASET Pilot Studies

Background

The ASET (Acetyl-Salicylic Elimination Trial) pilot studies recently investigated P2Y12 inhibitor monotherapy without aspirin immediately after percutaneous coronary intervention (PCI) in Brazil and Japan.

Objectives

This comparative analysis of the 2 ASET pilot studies aimed to summarize clinical outcomes and assess geographic and ethnic differences in baseline demographics and procedures.

Methods

Patients undergoing successful platinum-chromium everolimus-eluting stent implantation for chronic coronary syndrome were included. Following the index PCI, patients received prasugrel monotherapy with a maintenance dose of 10 mg/day in Brazil and 3.75 mg/day in Japan. The primary ischemic endpoint was the composite of cardiac death, spontaneous target vessel myocardial infarction, or definite stent thrombosis. The primary bleeding endpoint was Bleeding Academic Research Consortium types 3 and 5 bleeding at up to 3 months.

Results

Of 409 enrollments, 3-month follow-up was completed in 406 patients. Mean age was 64.3 ± 8.4 years, and 73% were men. Overall, post-TIMI flow grade 3 was achieved in 99.8%. Intravascular imaging for poststent optimization was used in 16.8% and 99.6% of treated lesions in Brazil and Japan, respectively. The primary ischemic and bleeding endpoints occurred in the same patient (0.2%). No stent thrombosis events occurred.

Conclusions

Prasugrel monotherapy following PCI was safe and feasible in selected low-risk chronic coronary syndrome patients after optimal platinum-chromium everolimus-eluting stent implantation regardless of the ethnic and geographic differences in baseline demographics, procedures, and prasugrel dosage. Randomized controlled trials will be needed to compare P2Y12 inhibitor monotherapy without aspirin with the current standard of care.

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.

An Aspirin-Free Versus Dual Antiplatelet Strategy for Coronary Stenting: STOPDAPT-3 Randomized Trial

BACKGROUND

Bleeding rates on dual antiplatelet therapy (DAPT) within 1 month after percutaneous coronary intervention (PCI) remain high in clinical practice, particularly in patients with acute coronary syndrome or high bleeding risk. Aspirin-free strategy might result in lower bleeding early after PCI without increasing cardiovascular events, but its efficacy and safety have not yet been proven in randomized trials.

METHODS

We randomly assigned 6002 patients with acute coronary syndrome or high bleeding risk just before PCI either to prasugrel (3.75 mg/day) monotherapy or to DAPT with aspirin (81-100 mg/day) and prasugrel (3.75 mg/day) after loading of 20 mg of prasugrel in both groups. The coprimary end points were major bleeding (Bleeding Academic Research Consortium 3 or 5) for superiority and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke) for noninferiority with a relative 50% margin.

RESULTS

The full analysis set population consisted of 5966 patients (no-aspirin group, 2984 patients; DAPT group, 2982 patients; age, 71.6±11.7 years; men, 76.6%; acute coronary syndrome, 75.0%). Within 7 days before randomization, aspirin alone, aspirin with P2Y12 inhibitor, oral anticoagulants, and intravenous heparin infusion were given in 21.3%, 6.4%, 8.9%, and 24.5%, respectively. Adherence to the protocol-specified antiplatelet therapy was 88% in both groups at 1 month. At 1 month, the no-aspirin group was not superior to the DAPT group for the coprimary bleeding end point (4.47% and 4.71%; hazard ratio, 0.95 [95% CI, 0.75-1.20]; Psuperiority=0.66). The no-aspirin group was noninferior to the DAPT group for the coprimary cardiovascular end point (4.12% and 3.69%; hazard ratio, 1.12 [95% CI, 0.87-1.45]; Pnoninferiority=0.01). There was no difference in net adverse clinical outcomes and each component of coprimary cardiovascular end point. There was an excess of any unplanned coronary revascularization (1.05% and 0.57%; hazard ratio, 1.83 [95%CI, 1.01-3.30]) and subacute definite or probable stent thrombosis (0.58% and 0.17%; hazard ratio, 3.40 [95% CI, 1.26-9.23]) in the no-aspirin group compared with the DAPT group.

CONCLUSIONS

The aspirin-free strategy using low-dose prasugrel compared with the DAPT strategy failed to attest superiority for major bleeding within 1 month after PCI but was noninferior for cardiovascular events within 1 month after PCI. However, the aspirin-free strategy was associated with a signal suggesting an excess of coronary events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04609111.

Definitions and Standardized Endpoints for Treatment of Coronary Bifurcations

The Bifurcation Academic Research Consortium (Bif-ARC) project originated from the need to overcome the paucity of standardization and comparability between studies involving bifurcation coronary lesions. This document is the result of a collaborative effort between academic research organizations and the most renowned interventional cardiology societies focused on bifurcation lesions in Europe, the United States, and Asia. This consensus provides standardized definitions for bifurcation lesions; the criteria to judge the side branch relevance; the procedural, mechanistic, and clinical endpoints for every type of bifurcation study; and the follow-up methods. Considering the complexity of bifurcation lesions and their evaluation, detailed instructions and technical aspects for site and core laboratory analysis of bifurcation lesions are also reported. The recommendations included within this consensus will facilitate pooled analyses and the effective comparison of data in the future, improving the clinical relevance of trials in bifurcation lesions, and the quality of care in this subset of patients.

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.

Less bleeding by omitting aspirin in non-ST-segment elevation acute coronary syndrome patients: Rationale and design of the LEGACY study

BACKGROUND

Early aspirin withdrawal, also known as P2Y12-inhibitor monotherapy, following percutaneous coronary intervention (PCI) for non-ST-segment elevation acute coronary syndrome (NSTE-ACS) can reduce bleeding without a trade-off in efficacy. Still the average daily bleeding risk is highest during the first months and it remains unclear if aspirin can be omitted immediately following PCI.

METHODS

The LEGACY study is an open-label, multicenter randomized controlled trial evaluating the safety and efficacy of immediate P2Y12-inhibitor monotherapy versus dual antiplatelet therapy (DAPT) for 12 months in 3,090 patients. Patients are randomized immediately following successful PCI for NSTE-ACS to 75-100 mg aspirin once daily versus no aspirin. The primary hypothesis is that immediately omitting aspirin is superior to DAPT with respect to major or minor bleeding defined as Bleeding Academic Research Consortium type 2, 3, or 5 bleeding, while maintaining noninferiority for the composite of all-cause mortality, myocardial infarction and stroke compared to DAPT.

CONCLUSIONS

The LEGACY study is the first randomized study that is specifically designed to evaluate the impact of immediately omitting aspirin, and thus treating patients with P2Y12-inhibitor monotherapy, as compared to DAPT for 12 months on bleeding and ischemic events within 12 months following PCI for NSTE-ACS.

Very short-term tissue coverage of the CD34 antibody-covered sirolimus-eluting stent: an optical coherence tomography study

It is well known that patients with acute myocardial infarction (AMI) have delayed vessel healing despite accelerated endothelial progenitor cells (EPC) mobilization. The COMBO stent is a unique biodegradable-polymer sirolimus-eluting stent with an anti-CD34 antibody coating which captures EPC and potentially promotes vessel healing. However, there are limited data about strut tissue coverage at the very short-term period after COMBO stent implantation. This was a prospective study to investigate strut tissue coverage within 1 month after COMBO stent implantation using optical coherence tomography (OCT). Struts fully covered with tissue were defined as covered, and struts with distance from lumen surface longer than strut plus polymer thickness were defined as malapposed. Mean tissue thickness was measured only in apposed struts. A total of 8173 struts of 33 lesions in 32 patients were analyzed at an average of 19.8 ± 4.6 days after COMBO stent implantation. In lesion-level analysis, the rate of covered struts was 89.6 ± 7.2%, the rate of malapposed struts was 0.9 ± 2.0% and mean tissue thickness was 46.8 ± 14.3 µm. In comparison between AMI (n = 12) and non-AMI (n = 21) patients, there were no significant differences in the rate of covered struts (88.4 ± 8.4% vs. 90.2 ± 6.6%, p = 0.48) and mean tissue thickness (46.8 ± 13.7 µm vs. 46.9 ± 15.0 µm, p = 0.98). Multivariable analysis demonstrated that time from implantation to OCT imaging was significantly associated with mean tissue thickness. The COMBO stent had substantial tissue coverage at the very short-term period after implantation even in AMI patients, and follow-up time had an impact on vessel healing.

P2Y12 Inhibitor Monotherapy Combined With Colchicine Following PCI in ACS Patients: The MACT Pilot Study

BACKGROUND

After a brief period of dual antiplatelet therapy, P2Y12 inhibitor monotherapy in the absence of aspirin effectively reduces bleeding without increasing recurrent ischemia in patients undergoing percutaneous coronary intervention (PCI). In addition, early anti-inflammatory therapies may have clinical benefits in acute coronary syndrome (ACS) patients.

OBJECTIVES

The aim of this study was to investigate the feasibility of ticagrelor or prasugrel P2Y12 inhibitor monotherapy combined with colchicine immediately after PCI in patients with ACS.

METHODS

This was a proof-of-concept pilot trial. ACS patients treated with drug-eluting stents were included. On the day after PCI, low-dose colchicine (0.6 mg daily) was administered in addition to ticagrelor or prasugrel maintenance therapy, whereas aspirin therapy was discontinued. The primary outcome was any stent thrombosis at 3 months. The key secondary outcomes were platelet reactivity measured by the VerifyNow assay (Accriva) before discharge and a reduction in high-sensitivity C-reactive protein (hs-CRP) over 1 month.

RESULTS

We enrolled 200 patients, 190 (95.0%) of whom completed the 3-month follow-up. The primary outcome occurred in 2 patients (1.0%): 1 definite and 1 probable stent thrombosis. The level of platelet reactivity overall was 27 ± 42 P2Y12 reaction units, and only 1 patient had high platelet reactivity (>208 P2Y12 reaction units). The hs-CRP levels decreased from 6.1 mg/L (IQR: 2.6-15.9 mg/L) at 24 hours after PCI to 0.6 mg/L (IQR: 0.4-1.2 mg/L) at 1 month (P < 0.001), and the prevalence of high-inflammation criteria (hs-CRP ≥2 mg/L) decreased from 81.8% to 11.8% (P < 0.001).

CONCLUSIONS

In ACS patients undergoing PCI, it is feasible to discontinue aspirin therapy and administer low-dose colchicine on the day after PCI in addition to ticagrelor or prasugrel P2Y12 inhibitors. This approach is associated with favorable platelet function and inflammatory profiles. (Mono Antiplatelet and Colchicine Therapy [MACT]; NCT04949516).

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).

Defining Strategies of Modulation of Antiplatelet Therapy in Patients With Coronary Artery Disease: A Consensus Document from the Academic Research Consortium

Antiplatelet therapy is the mainstay of pharmacologic treatment to prevent thrombotic or ischemic events in patients with coronary artery disease treated with percutaneous coronary intervention and those treated medically for an acute coronary syndrome. The use of antiplatelet therapy comes at the expense of an increased risk of bleeding complications. Defining the optimal intensity of platelet inhibition according to the clinical presentation of atherosclerotic cardiovascular disease and individual patient factors is a clinical challenge. Modulation of antiplatelet therapy is a medical action that is frequently performed to balance the risk of thrombotic or ischemic events and the risk of bleeding. This aim may be achieved by reducing (ie, de-escalation) or increasing (ie, escalation) the intensity of platelet inhibition by changing the type, dose, or number of antiplatelet drugs. Because de-escalation or escalation can be achieved in different ways, with a number of emerging approaches, confusion arises with terminologies that are often used interchangeably. To address this issue, this Academic Research Consortium collaboration provides an overview and definitions of different strategies of antiplatelet therapy modulation for patients with coronary artery disease, including but not limited to those undergoing percutaneous coronary intervention, and consensus statements on standardized definitions.

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.

De-escalation of antiplatelet therapy in patients with coronary artery disease: Time to change our strategy?

Dual antiplatelet therapy (DAPT) is the gold standard after acute coronary syndromes (ACS) or chronic coronary syndromes (CCS) undergoing percutaneous coronary intervention (PCI). Because local and systemic ischemic complications can occur particularly in the early phase (i.e. 1-3 months) after ACS or PCI, the synergistic platelet inhibition of aspirin and a P2Y₁₂ inhibitor is of the utmost importance in this early phase. Moreover, the use of the more potent P2Y₁₂ inhibitors prasugrel and ticagrelor have shown to further reduce the incidence of ischemic events compared to clopidogrel after an ACS. On the other hand, prolonged and potent antiplatelet therapy are inevitably associated with increased bleeding, which unlike thrombotic risk, tends to be stable over time and may outweigh the benefit of reducing ischemic events in these patients. The duration and composition of antiplatelet therapy remains a topic of debate in cardiology due to competing ischemic and bleeding risks, with guidelines and recommendations considerably evolving in the past years. An emerging strategy, called "de-escalation", consisting in the administration of a less intense antithrombotic therapy after a short course of standard DAPT, has shown to reduce bleeding without any trade-off in ischemic events. De-escalation may be achieved with different antithrombotic strategies and can be either unguided or guided by platelet function or genetic testing. The aim of this review is to summarize the evidence and provide practical recommendations on the use of different de-escalation strategies in patients with ACS and CCS.

Dual antiplatelet therapy duration after percutaneous coronary intervention in high bleeding risk: a meta-analysis of randomized trials

AIMS

The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in patients at high bleeding risk (HBR) is still debated. The current study, using the totality of existing evidence, evaluated the impact of an abbreviated DAPT regimen in HBR patients.

METHODS AND RESULTS

A systematic review and meta-analysis was performed to search randomized clinical trials comparing abbreviated [i.e. very-short (1 month) or short (3 months)] with standard (≥6 months) DAPT in HBR patients without indication for oral anticoagulation. A total of 11 trials, including 9006 HBR patients, were included. Abbreviated DAPT reduced major or clinically relevant non-major bleeding [risk ratio (RR): 0.76, 95% confidence interval (CI): 0.61-0.94; I2 = 28%], major bleeding (RR: 0.80, 95% CI: 0.64-0.99, I2 = 0%), and cardiovascular mortality (RR: 0.79, 95% CI: 0.65-0.95, I2 = 0%) compared with standard DAPT. No difference in all-cause mortality, major adverse cardiovascular events, myocardial infarction, or stent thrombosis was observed. Results were consistent, irrespective of HBR definition and clinical presentation.

CONCLUSION

In HBR patients undergoing PCI, a 1- or 3-month abbreviated DAPT regimen was associated with lower bleeding and cardiovascular mortality, without increasing ischaemic events, compared with a ≥6-month DAPT regimen.

STUDY REGISTRATION

PROSPERO registration number CRD42021284004.

Prasugrel Monotherapy After Percutaneous Coronary Intervention With Biodegradable-Polymer Platinum-Chromium Everolimus Eluting Stent for Japanese Patients With Chronic Coronary Syndrome (ASET-JAPAN)

BACKGROUND

P2Y12 inhibitor monotherapy without aspirin immediately after percutaneous coronary intervention (PCI) has not been tested in East Asian patients, so in this study we aimed to assess the safety and feasibility of reduced dose (3.75 mg/day) prasugrel monotherapy in Japanese patients presenting with chronic coronary syndrome (CCS).Methods and Results: ASET-JAPAN is a prospective, multicenter, single-arm pilot study that completed enrolment of 206 patients from 12 Japanese centers in September 2022. Patients with native de-novo coronary lesions and a SYNTAX score <23 were treated exclusively with biodegradable-polymer platinum-chromium everolimus-eluting stent(s). Patients were loaded with standard dual antiplatelet therapy (DAPT) and following successful PCI and optimal stent deployment, they received low-dose prasugrel (3.75 mg/day) monotherapy for 3 months. The primary ischemic endpoint was a composite of cardiac death, spontaneous target-vessel myocardial infarction, or definite stent thrombosis. The primary bleeding endpoint was Bleeding Academic Research Consortium (BARC) type 3 or 5. At 3-month follow-up, there were no primary bleeding or ischemic events, or any stent thrombosis.

CONCLUSIONS

This pilot study showed the safety and feasibility of prasugrel monotherapy in selected low-risk Japanese patients with CCS. This "aspirin-free" strategy may be a safe alternative to traditional DAPT following PCI.

Reduced-dose prasugrel monotherapy without aspirin after PCI with the SYNERGY stent in East Asian patients presenting with chronic coronary syndromes or non-ST-elevation acute coronary syndromes: rationale and design of the ASET Japan pilot study

The Acetyl Salicylic Elimination Trial (ASET) Japan pilot study is a multicentre, single-arm, open-label, proof-of-concept study with a stopping rule based on the occurrence of definite stent thrombosis. This study aims to demonstrate the feasibility and safety of low-dose prasugrel monotherapy following percutaneous coronary intervention (PCI) in Japanese patients presenting with chronic coronary syndromes (CCS) or non-ST-elevation acute coronary syndromes (NSTE-ACS). Four hundred patients with a SYNTAX score <23 requiring PCI due to CCS or NSTE-ACS will be screened and considered eligible for the study. The enrolment is planned in two phases: 1) 200 patients presenting with CCS, followed by 2) 200 patients presenting with NSTE-ACS. After optimal PCI with implantation of a SYNERGY (Boston Scientific) stent, patients will be enrolled and loaded with prasugrel 20 mg, followed by a maintenance dose of prasugrel 3.75 mg once daily without aspirin continued for 3 months in Phase 1 (CCS patients), and for 12 months in Phase 2 (NSTE-ACS patients). After these follow-up periods, prasugrel will be replaced by standard antiplatelet therapy according to local practice. The primary endpoint is a composite of cardiac death, target vessel myocardial infarction, or definite stent thrombosis after the index procedure. The primary bleeding endpoint is any Bleeding Academic Research Consortium type 3 or 5 bleeding occurring within 3 months of the index PCI for CCS patients, or 12 months for NSTE-ACS patients. The ASET Japan study is designed to demonstrate the feasibility and safety of reduced-dose prasugrel monotherapy after PCI in East Asian patients with acute and chronic coronary syndromes.

Platelet P2Y12 Inhibitor Monotherapy after Percutaneous Coronary Intervention: An Emerging Option for Antiplatelet Therapy De-escalation

Antiplatelet therapy is considered essential for secondary prevention of ischemic heart disease. After percutaneous coronary intervention (PCI), temporary dual antiplatelet therapy (DAPT), a combination consisting of aspirin and an oral P2Y12 receptor blocker, is recommended. In the long term, this strategy results in more bleeding than antiplatelet therapy with aspirin alone. Therefore, to reduce bleeding, an increasing trend has been to keep DAPT as short as clinically acceptable, after which aspirin monotherapy is continued. Another option to diminish bleeding is to discontinue aspirin at the moment of DAPT cessation after PCI, and to continue on P2Y12 blocker monotherapy. This survey reviews the evidence on P2Y12 blocker monotherapy. Some clinical guidance will be provided on when and in whom P2Y12 inhibitor monotherapy may be applied after DAPT cessation following PCI.

Antithrombotic Treatment in Coronary Artery Disease

Coronary artery disease exhibits growing mortality and morbidity worldwide despite the advances in pharmacotherapy and coronary intervention. Coronary artery disease is classified in the acute coronary syndromes and chronic coronary syndromes according to the most recent guidelines of the European Society of Cardiology. Antithrombotic treatment is the cornerstone of therapy in coronary artery disease due to the involvement of atherothrombosis in the pathophysiology of the disease. Administration of antiplatelet agents, anticoagulants and fibrinolytics reduce ischemic risk, which is amplified early post-acute coronary syndromes or post percutaneous coronary intervention; though, antithrombotic treatment increases the risk for bleeding. The balance between ischemic and bleeding risk is difficult to achieve and is affected by patient characteristics, procedural parameters, concomitant medications and pharmacologic characteristics of the antithrombotic agents. Several pharmacological strategies have been evaluated in patients with coronary artery disease, such as the effectiveness and safety of antithrombotic agents, optimal dual antiplatelet treatment schemes and duration, aspirin de-escalation strategies of dual antiplatelet regimens, dual inhibition pathway strategies as well as triple antithrombotic therapy. Future studies are needed in order to investigate the gaps in our knowledge, including special populations.

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.

Short dual antiplatelet therapy and dual antiplatelet therapy de-escalation after primary percutaneous intervention: For whom and how

Dual antiplatelet therapy (DAPT) for 6-12 months, followed by lifelong aspirin monotherapy is considered an effective standard therapy for the prevention of thrombo-ischemic events in patients with acute and chronic coronary syndrome (ACS, CCS) undergoing percutaneous coronary intervention (PCI) or after a primarily conservative treatment decision. In ACS patients, the stronger P2Y12-inhibitors ticagrelor or prasugrel are recommended in combination with aspirin unless the individual bleeding risk is high and shortening of DAPT is warranted or clopidogrel is preferred. However, also in patients at low individual bleeding risk, DAPT is associated with a higher risk of bleeding. In recent years, new antithrombotic treatment strategies, such as shortening DAPT followed by early P2Y12-inhibitor monotherapy and de-escalating DAPT from potent P2Y12-inhibitors to clopidogrel by maintaining DAPT duration time, have been investigated in clinical trials and shown to reduce bleeding complications in cardiovascular high-risk patients without negative effects on ischemic events. In this review, we summarize the current knowledge and discuss its implication on future antithrombotic strategies in terms of a personalized medicine.

The stent in the high-bleeding risk patient: antiplatelet monotherapy?

Dual antiplatelet therapy (DAPT) is the recommended treatment after percutaneous coronary intervention (PCI). The introduction into clinical practice of new drug-eluting stents (DESs) with significantly improved safety profiles has made it possible to shorten the DAPT. Randomized studies have established the superiority of DES over bare metal stents in high-bleeding risk (HBR) patients treated with antiplatelet monotherapy after 1 month of DAPT from PCI. This regimen has been adopted in randomized trials comparing different DES in patients with HBR. Furthermore, antiplatelet monotherapy after 1 month of DAPT from PCI has been shown to reduce bleeding risk without increasing ischaemic events compared with a conventional DAPT regimen (3-12 months) in a recent randomized study that included HBR patients treated with DES. Parallel to the trend of shortening DAPT, there is growing debate about which antiplatelet monotherapy is optimal after discontinuation of DAPT, with some recent studies exploring the paradigm shift from aspirin monotherapy to P2Y12 inhibitor monotherapy. Finally, future studies are underway to evaluate the clinical effect of monotherapy with ticagrelor or prasugrel directly after implantation of DES thus eliminating DAPT.

P2Y12 Inhibitor Monotherapy after Percutaneous Coronary Intervention

In patients with acute and chronic coronary artery disease undergoing percutaneous coronary intervention (PCI), dual antiplatelet therapy (DAPT) has been the cornerstone of pharmacotherapy for the past two decades. Although its antithrombotic benefit is well established, DAPT is associated with an increased risk of bleeding, which is independently associated with poor prognosis. The improvement of the safety profiles of drug-eluting stents has been critical in investigating and implementing shorter DAPT regimens. The introduction into clinical practice of newer generation oral P2Y₁₂ inhibitors such as prasugrel and ticagrelor, which provide more potent and predictable platelet inhibition, has questioned the paradigm of standard DAPT durations after coronary stenting. Over the last five years, several trials have assessed the safety and efficacy of P2Y₁₂ inhibitor monotherapy after a short course of DAPT in patients treated with PCI. Moreover, ongoing studies are testing the role of P2Y₁₂ inhibitor monotherapy immediately after PCI in selected patients. In this review, we provide up-to-date evidence on the efficacy and safety of P2Y₁₂ inhibitor monotherapy after a short period of DAPT compared to DAPT in patients undergoing PCI as well as outcomes associated with P2Y₁₂ inhibitor monotherapy compared to aspirin for long-term prevention.

De-escalation of antiplatelet therapy in acute coronary syndromes: Why, how and when?

The synergistic blockade of the key platelet signaling pathways of cyclooxygenase-1 blockade and P2Y12 signaling by combining aspirin plus a potent P2Y12 inhibitor (prasugrel or ticagrelor), the so called dual antiplatelet treatment (DAPT), has represented the antithrombotic regimen of choice in patients with acute coronary syndrome (ACS) for nearly a decade. Nevertheless, the use of such antiplatelet treatment regimen, while reduced the risk of thrombotic complications, it is inevitably associated with increased bleeding and this risk may outweigh the benefit of a reduction of ischemic events in specific subgroup of patients. In light of the adverse prognostic implications of a bleeding complication, there has been a great interest in the development of antiplatelet regimens aimed at reducing bleeding without any trade-off in ischemic events. The fact that the ischemic risk is highest in the early phase after an ACS while the risk of bleeding remains relatively stable over time has represented the rationale for the implementation of a more intense antithrombotic regimen early after an ACS, followed by a less intense antithrombotic regimen thereafter. This practice, known as a "de-escalation" strategy, represents one of the more promising approaches for personalization of antithrombotic therapy in ACS. In this review we discuss the rationale, appraise the evidence and provide practical recommendations on the use of a de-escalation strategy of antiplatelet therapy in patients with an ACS.

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.

Definitions and Standardized Endpoints for Treatment of Coronary Bifurcations

The Bifurcation Academic Research Consortium (Bif-ARC) project originated from the need to overcome the paucity of standardization and comparability between studies involving bifurcation coronary lesions. This document is the result of a collaborative effort between academic research organizations and the most renowned interventional cardiology societies focused on bifurcation lesions in Europe, the United States, and Asia. This consensus provides standardized definitions for bifurcation lesions; the criteria to judge the side branch relevance; the procedural, mechanistic, and clinical endpoints for every type of bifurcation study; and the follow-up methods. Considering the complexity of bifurcation lesions and their evaluation, detailed instructions and technical aspects for site and core laboratory analysis of bifurcation lesions are also reported. The recommendations included within this consensus will facilitate pooled analyses and the effective comparison of data in the future, improving the clinical relevance of trials in bifurcation lesions, and the quality of care in this subset of patients.

Association Between Platelet Reactivity and Long-Term Bleeding Complications After Percutaneous Coronary Intervention According to Diabetes Status

The relation between diabetes mellitus (DM) and bleeding complications after percutaneous coronary intervention (PCI) is controversial. This study investigates the role of low platelet reactivity (LPR) in the bleeding risk stratification of patients who underwent PCI according to DM status. A total of 472 patients who underwent PCI on aspirin and clopidogrel were included retrospectively. Platelet reactivity was assessed using the VerifyNow P2Y(12) assay. LPR was defined as platelet reactivity unit ≤178. The primary end point was the occurrence of any bleeding at 5 years stratified by DM status and LPR. DM was present in 30.5% of patients. LPR was less frequent in patients with DM (p = 0.077). Overall, 11.9% of patients experienced a bleeding complication at 5 years. The incidence of bleeding did not differ in subjects with and without DM (p = 0.24). LPR had a similar value for stratifying the increased bleeding risk in patients with and without DM (interaction p between DM and LPR 0.69). A stepwise increase in the crude rates of bleeding complications was observed across patients with and without LPR and DM (log-rank p = 0.004), with those affected by both conditions having the highest crude incidence rate. In conclusion, on top of aspirin, approximately 1/3 of patients who underwent PCI on clopidogrel have LPR. Assessment of LPR provides a significant incremental value for predicting bleeding irrespective of DM status. Although the presence of DM per se does not increase the incidence of hemorrhagic complications, the coexistence of DM and LPR identifies the subgroup with the highest bleeding risk.

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.

Angiography-derived physiology guidance vs usual care in an All-comers PCI population treated with the healing-targeted supreme stent and Ticagrelor monotherapy: PIONEER IV trial design

BACKGROUND

Current ESC guidelines recommend the use of intra-coronary pressure guidewires for functional assessment of intermediate-grade coronary stenoses. Angiography-derived quantitative flow ratio (QFR) is a novel method of assessing these stenoses, and guiding percutaneous coronary intervention (PCI).

METHODS/DESIGN

The PIONEER IV trial is a prospective, all-comers, multi-center trial, which will randomize 2,540 patients in a 1:1 ratio to PCI guided by angiography-derived physiology or usual care, with unrestricted use in both arms of the Healing-Targeted Supreme sirolimus-eluting stent (HT Supreme). The stent's fast, biologically healthy, and robust endothelial coverage allows for short dual-antiplatelet therapy (DAPT); hence the antiplatelet regimen of choice is 1-month DAPT, followed by ticagrelor monotherapy. In the angiography-derived physiology guided arm, lesions will be functionally assessed using on-line QFR, with stenting indicated in lesions with a QFR ≤0.80. Post-stenting, QFR will be repeated in the stented vessel(s), with post-dilatation or additional stenting recommended if the QFR<0.91 distal to the stent, or if the delta QFR (across the stent) is >0.05. Usual care PCI is performed according to standard clinical practice. The primary endpoint is a non-inferiority comparison of the patient-oriented composite endpoint (POCE) of all-cause death, any stroke, any myocardial infarction, or any clinically, and physiologically driven revascularization with a non-inferiority risk-difference margin of 3.2%, at 1-year post-procedure. Clinical follow-up will be up to 3 years.

SUMMARY

The PIONEER IV trial aims to demonstrate non-inferiority of QFR-guided PCI to usual care PCI with respect to POCE at 1-year in patients treated with HT Supreme stents and ticagrelor monotherapy.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov UNIQUE IDENTIFIER: NCT04923191 CLASSIFICATIONS: Interventional Cardiology.

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.

Antiplatelet therapy after percutaneous coronary intervention: current status and future perspectives

Antiplatelet therapy after percutaneous coronary intervention (PCI) has been changing in parallel with the development of drug-eluting stents (DES) and antiplatelet agents. The recommendation of dual antiplatelet therapy duration is getting shorter due to the decreased risk of stent thrombosis in new-generation DES, the use of a P2Y₁₂ inhibitor as a monotherapy, and the increasing prevalence of high bleeding risk patients. Antithrombotic therapy after PCI has also changed due to the introduction of direct oral anticoagulants. Aspirin-free P2Y₁₂ inhibitor monotherapy is now being evaluated in several prospective studies as a novel strategy of antiplatelet therapy after PCI. This review shows a current status and provides future perspectives for the antiplatelet therapy after PCI.

Role of Monotherapy with a P2Y12 Inhibitor for Secondary Prevention in Patients with Established Atherosclerosis

PURPOSE OF REVIEW

The role of monotherapy with a P2Y12 inhibitor for secondary prevention of cardiovascular diseases has been assessed in several randomized trials. In this article, we summarize the evidence regarding P2Y12 monotherapy for secondary prevention in each one of the major vascular territories.

RECENT FINDINGS

Available data including a large recent meta-analysis show no differences in terms of all-cause death, vascular death, stroke, and a minor difference of the risk of myocardial infarction with P2Y12 monotherapy as compared to dual antiplatelet therapy. Overall, mono antiplatelet therapy with aspirin and the P2Y12 inhibitors appear similar in efficacy. However, there are clinical conditions that may suggest one drug regimen over another in secondary prevention. The risk of bleeding must always be weighed in each patient individually for the optimal choice of the antiplatelet regimen.

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI) update 2022

Primary Percutaneous Coronary Intervention (PCI) has significantly contributed to reducing the mortality of patients with ST-segment elevation myocardial infarction (STEMI) even in cardiogenic shock and is now the standard of care in most of Japanese institutions. The Task Force on Primary PCI of the Japanese Association of Cardiovascular Interventional and Therapeutics (CVIT) society proposed an expert consensus document for the management of acute myocardial infarction (AMI) focusing on procedural aspects of primary PCI in 2018. Updated guidelines for the management of AMI were published by the European Society of Cardiology (ESC) in 2017 and 2020. Major changes in the guidelines for STEMI patients included: (1) radial access and drug-eluting stents (DES) over bare-metal stents (BMS) were recommended as a Class I indication, (2) complete revascularization before hospital discharge (either immediate or staged) is now considered as Class IIa recommendation. In 2020, updated guidelines for Non-ST-Elevation Myocardial Infarction (NSTEMI) patients, the followings were changed: (1) an early invasive strategy within 24 h is recommended in patients with NSTEMI as a Class I indication, (2) complete revascularization in NSTEMI patients without cardiogenic shock is considered as Class IIa recommendation, and (3) in patients with atrial fibrillation following a short period of triple antithrombotic therapy, dual antithrombotic therapy (e.g., DOAC and single oral antiplatelet agent preferably clopidogrel) is recommended, with discontinuation of the antiplatelet agent after 6 to 12 months. Furthermore, an aspirin-free strategy after PCI has been investigated in several trials those have started to show the safety and efficacy. The Task Force on Primary PCI of the CVIT group has now proposed the updated expert consensus document for the management of AMI focusing on procedural aspects of primary PCI in 2022 version.

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.

Aspirin in the Modern Era of Cardiovascular Disease Prevention

Aspirin’s antithrombotic effects have a long-established place in the prevention of cardiovascular disease (CVD), and its traditional use as a core therapy for secondary prevention of CVD is well recognized. However, with the advent of newer antiplatelet agents and an increasing understanding of aspirin’s bleeding risks, its role across the full spectrum of modern CVD prevention has become less certain. As a consequence, recent trials have begun investigating aspirin-free strategies in secondary prevention. For example, a contemporary metanalysis of trials that assessed P2Y₁₂ inhibitor monotherapy versus prolonged (≥ 12 months) dual antiplatelet therapy (which includes aspirin) after percutaneous coronary intervention reported a lower risk of major bleeding and no increase in stent thrombosis, all-cause mortality, myocardial infarction (MI), or stroke in the P2Y₁₂ monotherapy group.

In contrast to secondary prevention, aspirin’s role in primary prevention has always been more controversial. While historical trials reported a reduction in MI and stroke, more contemporary trials have suggested diminishing benefit for aspirin in this setting, with no reduction in hard outcomes, and some primary prevention trials have even indicated a potential for harm. In this review, we discuss how changing population demographics, enhanced control of lipids and blood pressure, changes in the definition of outcomes like MI, evolution of aspirin formulations, and updated clinical practice guidelines have all impacted the use of aspirin for primary and secondary CVD prevention.

Complications related to veno-arterial extracorporeal membrane oxygenation in patients with acute myocardial infarction: VA-ECMO complications in AMI

BACKGROUND

Among various mechanical support devices, veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is the last resort for acute myocardial infarction (AMI) patients complicated with refractory cardiogenic shock or cardiac arrest. The purpose of this study was to investigate the V-A ECMO-related complications in AMI patients who underwent percutaneous coronary intervention (PCI), and to find the association between complications and in-hospital death in that population.

METHODS

We retrospectively included 101 AMI patients who received V-A ECMO and underwent PCI to the culprit lesion, and divided them into the survivor group (n=43) and the in-hospital death group (n=58). We compared the clinical characteristics and outcomes including complications between the 2 groups, and performed multivariate logistic regression analysis to find factors associated with in-hospital death and major bleeding.

RESULTS

The incidence of major bleeding including V-A ECMO site bleeding and intracranial hemorrhage was higher in the in-hospital death group (34.5%) than in the survivor group (7%) (p=0.001). Multivariate logistic regression analysis revealed that final thrombolysis in myocardial infarction (TIMI) flow grade ≤2 (OR 4.453, 95% CI1.427-13.894, p=0.010) and major bleeding (OR 4.986, 95% CI1.277-19.466, p=0.021) were significantly associated with in-hospital death. Out-of-hospital cardiac arrest (OHCA) was significantly associated with major bleeding (OR 3.881, 95% CI 1.358-11.089, p=0.011).

CONCLUSIONS

In AMI patients who received V-A ECMO and underwent PCI, final TIMI flow grade ≤2 and major bleeding were associated with in-hospital death. OHCA was closely associated with major bleeding.

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.

Antiplatelet Therapy After Percutaneous Coronary Intervention - Past, Current and Future Perspectives

Optimal antiplatelet therapy after percutaneous coronary intervention (PCI) has been changed in parallel with the improvements of coronary stent and antiplatelet therapy. Over the past 25 years, dual antiplatelet therapy (DAPT) with aspirin plus P2Y₁₂inhibitor has been the standard of care used after coronary stent implantation. First-generation drug-eluting stent (DES) appeared to increase the risk of late stent thrombosis, and duration of DAPT was prolonged to 12 months. DAPT duration up to 12 months was the dominant strategy after DES implantation in the subsequent >10 years, although there was no dedicated randomized controlled trial supporting this recommendation. The current recommendation of DAPT duration is getting shorter due to the development of new-generation DES, use of a P2Y₁₂inhibitor as a monotherapy, and the increasing prevalence of high-bleeding risk patients. Furthermore, an aspirin-free strategy is now emerging as one of the novel strategies of antiplatelet therapy after PCI. This review gives an overview of the history of antiplatelet therapy and provides current and future perspectives on antiplatelet therapy after PCI.

Practical Assessment of the Tradeoff between Fatal Bleeding and Coronary Thrombotic Risks using the Academic Research Consortium for High Bleeding Risk Criteria

Aims: We aimed to establish a practical method for the assessment of tradeoff between thrombotic and bleeding risks.

Methods: We aimed to investigate the balance between bleeding risk and coronary thrombotic risk according to the number of the Academic Research Consortium for high bleeding risk (ARC-HBR) criteria in the multicenter prospective ST/non-ST elevation myocardial infarction (STEMI/NSTEMI) registry (N=12,093). Patients were divided as follows by the number of ARC-HBR criteria fulfilled: group 0, 0 major with ≤ 1 minor (N=6,792); group 1, 1 major with 0 minor (N=1,705); group 2, 0 major with ≥ 2 minors (N=790); group 3, 1 major with ≥ 1 minor (N=1,709); group 4, 2 majors with ≥ 0 minors (N=861); and group 5, ≥ 3 majors with ≥ 0 minor (N=236). We assessed the acute-phase absolute risk differences between bleeding and coronary thrombotic events in each group.

Results: At 7-day follow-up, all patients (groups 0–5) had a higher risk of major bleeding than that of any myocardial infarction (MI). Patients at ARC-HBR (groups 1–5) had a balanced risk between fatal MI and fatal bleeding, whereas patients at non-ARC-HBR (group 0) had a higher risk of fatal MI than that of fatal bleeding.

Conclusions: All STEMI/NSTEMI patients have a relatively high risk of major bleeding as compared with the risk of any MI in the acute phase. The ARC-HBR criteria would be a practical tool for assessing the tradeoff between fatal bleeding and fatal MI risks. This practical assessment would be helpful for the optimal decision-making of appropriate treatment strategy considering the balance between bleeding and coronary thrombotic risks.