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

Reassessing the role of aspirin in patients with coronary artery disease

INTRODUCTION

Recent data question the use of aspirin as a bedrock of antiplatelet therapy in patients with arterial diseases. There are controversies regarding the efficacy of aspirin therapy with respect to specific demographic characteristics, dose and formulations, benefit in primary prevention, and duration in secondary prevention. Importantly, to balance the ischemic benefits and the risk of excessive bleeding following a coronary event, recent studies have investigated strategies to discontinue aspirin therapy and continue with P2Y12 receptor inhibitor monotherapy. However, the precise time when to discontinue aspirin is still unresolved.

AREAS COVERED

Evidence from recent studies evaluating the role of aspirin in primary and secondary prevention studies was collected from a selective literature search. In this review, the authors discuss current recommendations, large-scale studies of aspirin therapy, controversies, and potential future opportunities for aspirin therapy.

EXPERT OPINION

With the new evidence showing lower bleeding risk with aspirin-free strategies in both primary and secondary prevention studies, the role of aspirin is being revaluated with P2Y12 receptor inhibitor monotherapy. The potential benefits of novel aspirin formulations and alternative delivery methods, such as inhaled aspirin, are undergoing much-needed investigation with the goal of optimizing care for a wide range of patients.

Nomogram based on virtual hyperemic pullback pressure gradients for predicting the suboptimal post-PCI QFR outcome after stent implantation

BACKGROUND

Growing evidence shows an association between higher post-PCI quantitative flow ratios (QFR) and improved clinical prognosis, however, no models are available to predict suboptimal QFRs (< 0.91) after angiographically successful PCI. This study aims to establish a prediction nomogram for this domain.

METHODS

This study included 450 vessels derived from 421 consecutive patients enrolled in the PIONEER IV trial, which were randomly assigned in a 1:1 ratio to a training (N = 225) and internal validation (N = 225) set, with external validation performed in 97 vessels from 95 consecutive patients enrolled in the ASET Japan trial. LASSO regression was used for optimal feature selection, and multivariate logistic regression was subsequently utilized to construct the nomogram. The performance of the nomograms was assessed and validated by area under the receiver operating characteristics curve (AUC), calibration curves, decision curve analysis, and clinical impact curves.

RESULTS

The nomogram was constructed incorporating a novel metric, quantitative flow ratio derived pullback pressure gradient (QFR-PPG), alongside four conventional parameters: left anterior descending artery disease, pre-procedural QFR, reference vessel diameter, and percent diameter stenosis. AUCs of the nomogram were 0.866 (95%CI:0.818-0.914), 0.784 (95% CI:0.722-0.847), and 0.781 (95% CI:0.682-0.879) in the training, internal validation and external validation sets, respectively. Bias-corrected curves revealed a strong consistency between actual observations and prediction.

CONCLUSION

The risk of a suboptimal post-PCI QFR in patients after angiographically successful PCI can be effectively predicted using a nomogram incorporating five variables available pre-PCI, with its performance and clinical predictive value confirming its utility in helping clinicians with decision-making and planning revascularization.

TRIAL REGISTRATION

Registered on clinicaltrial.gov (NCT04923191 and NCT05117866).

CVIT expert consensus document on primary percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS) in 2024

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 Intervention and Therapeutics (CVIT) proposed an expert consensus document for the management of acute myocardial infarction (AMI) focusing on procedural aspects of primary PCI in 2018 and updated in 2022. Recently, the European Society of Cardiology (ESC) published the guidelines for the management of acute coronary syndrome in 2023. Major new updates in the 2023 ESC guideline include: (1) intravascular imaging should be considered to guide PCI (Class IIa); (2) timing of complete revascularization; (3) antiplatelet therapy in patient with high-bleeding risk. Reflecting rapid advances in the field, the Task Force on Primary PCI of the CVIT group has now proposed an updated expert consensus document for the management of ACS focusing on procedural aspects of primary PCI in 2024 version.

Frequency of periprocedural myocardial injury and infarction stratified by cardiac troponin I and cardiac troponin T

BACKGROUND

There are different definitions of periprocedural myocardial infarction (PPMI) both in terms of thresholds for cardiac biomarkers and the ancillary criteria for myocardial ischemia. Cardiac Troponin I (cTnI) and cardiac Troponin T (cTnT) are used interchangeably to diagnose PPMI.

OBJECTIVES

This study evaluated the frequency of periprocedural myocardial injury and infarction as defined by the Society of Cardiovascular Angiography & Interventions (SCAI), the Academic Research Consortium-2 (ARC-2), and the 4th Universal definition of MI (4UDMI) stratified using cTnT versus cTnI, among patients with chronic coronary syndrome (CCS) and unstable angina.

RESULTS

Among 830 patients, PPMI rates according to the SCAI, ARC2 and 4UDMI criteria were 4.34 %, 2.05 %, and 4.94 % respectively, with higher rates seen for all definitions when using cTnI versus cTnT (SCAI: 9.84 % vs. 1.91 %, p < 0.001; ARC 2: 3.15 % vs. 1.56 %, p = 0.136; and 4UDMI 5.91 % vs. 4.51 %, p = 0.391). Minor and major periprocedural myocardial injury was respectively observed in 58.31 % and 27.10 % of patients, with rates of both significantly higher when using cTnI versus cTnT (Minor: 69.29 % vs. 53.47 %, p < 0.001, Major: 49.21 % vs. 17.36 %, p < 0.001).

CONCLUSIONS

Among patients with CCS and unstable angina, PPMIs defined by SCAI occurred more frequently when using cTnI as opposed to cTnT, whereas the type of troponin had no impact on the incidence of PPMIs according to the ARC-2 and 4UDMI.

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.

Drug-eluting stents for coronary artery disease in the perspective of bibliometric analysis

Drug-eluting stents (DES) play a crucial role in treating coronary artery disease (CAD) by preventing restenosis. These stents are coated with drug carriers that release antiproliferative drugs within the vessel. Over the past two decades, DES have been employed in clinical practice using various materials, polymers, and drug types. Despite optimizations in their design and materials to enhance biocompatibility and antithrombotic properties, evaluating their long-term efficacy and safety necessitates improved clinical follow-up and monitoring. To delineate future research directions, this study employs a bibliometric analysis approach. We comprehensively surveyed two decades' worth of literature on DES for CAD using the Web of Science Core Collection (WOSCC). Out of 5,778 articles, we meticulously screened them based on predefined inclusion and exclusion criteria. Subsequently, we conducted an in-depth analysis encompassing annual publication trends, authorship affiliations, journal affiliations, keywords, and more. Employing tools such as Excel 2021, CiteSpace 6.2R3, VOSviewer 1.6.19, and Pajek 5.17, we harnessed bibliometric methods to derive insights from this corpus. Analysis of annual publication data indicates a recent stabilisation or even a downward trend in research output in this area. The United States emerged as the leading contributor, with Columbia University and CRF at the forefront in both publication output and citation impact. The most cited document pertained to standardized definitions for clinical endpoints in coronary stent trials. Our author analysis identifies Patrick W. Serruys as the most prolific contributor, underscoring a dynamic exchange of knowledge within the field.Moreover, the dual chart overlay illustrates a close interrelation between journals in the "Medicine," "Medical," and "Clinical" domains and those in "Health," "Nursing," and "Medicine." Frequently recurring keywords in this research landscape include DES coronary artery disease, percutaneous coronary intervention, implantation, and restenosis. This study presents a comprehensive panorama encompassing countries, research institutions, journals, keyword distributions, and contributions within the realm of DES therapy for CAD. By highlighting keywords exhibiting recent surges in frequency, we elucidate current research hotspots and frontiers, thereby furnishing novel insights to guide future researchers in this evolving field.

Preprocedural physiological assessment of coronary disease patterns to predict haemodynamic outcomes post-PCI

BACKGROUND

Even with intracoronary imaging-guided stent optimisation, suboptimal haemodynamic outcomes post-percutaneous coronary intervention (PCI) can be related to residual lesions in non-stented segments. Preprocedural assessment of pathophysiological coronary artery disease (CAD) patterns could help predict the physiological response to PCI.

AIMS

The aim of this study was to assess the relationship between preprocedural pathophysiological haemodynamic patterns and intracoronary imaging findings, as well as their association with physiological outcomes immediately post-PCI.

METHODS

Data from 206 patients with chronic coronary syndrome enrolled in the ASET-JAPAN study were analysed. Pathophysiological CAD patterns 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 pullback pressure gradient (PPG) index. Intracoronary imaging in stented segments after stent optimisation was also analysed.

RESULTS

In the multivariable analysis, diffuse disease - defined by the pre-PCI μQFR-PPG index - was an independent factor for predicting a post-PCI μQFR <0.91 (per 0.1 decrease of PPG index, odds ratio 1.57, 95% confidence interval: 1.07-2.34; p=0.022), whereas the stent expansion index (EI) was not associated with a suboptimal post-PCI μQFR. Among vessels with an EI ≥80% and post-PCI μQFR <0.91, 84.0% of those vessels had a diffuse pattern preprocedure. There was no significant difference in EI between vessels with diffuse disease and those with focal disease. The average plaque burden in the stented segment was significantly larger in vessels with a preprocedural diffuse CAD pattern.

CONCLUSIONS

A physiological diffuse pattern preprocedure was an independent factor in predicting unfavourable immediate haemodynamic outcomes post-PCI, even after stent optimisation using intracoronary imaging. Preprocedural assessment of CAD patterns could identify patients who are likely to exhibit superior immediate haemodynamic outcomes following PCI.