Pharmacogenetics of Antiplatelet Therapy.

Antiplatelet therapy is used in the treatment of patients with acute coronary syndromes, stroke, and those undergoing percutaneous coronary intervention. Clopidogrel is the most widely used antiplatelet P2Y12 inhibitor in clinical practice. Genetic variation in CYP2C19 may influence its enzymatic activity, resulting in individuals who are carriers of loss-of-function CYP2C19 alleles and thus have reduced active clopidogrel metabolites, high on-treatment platelet reactivity, and increased ischemic risk. Prospective studies have examined the utility of CYP2C19 genetic testing to guide antiplatelet therapy, and more recently published meta-analyses suggest that pharmacogenetics represents a key treatment strategy to individualize antiplatelet therapy. Rapid genetic tests, including bedside genotyping platforms that are validated and have high reproducibility, are available to guide selection of P2Y12 inhibitors in clinical practice. The aim of this review is to provide an overview of the background and rationale for the role of a guided antiplatelet approach to enhance patient care.

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.

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

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

Ticagrelor monotherapy for acute coronary syndrome: an individual patient data meta-analysis of TICO and T-PASS trials.

BACKGROUND AND AIMS: In patients with acute coronary syndrome (ACS), dual antiplatelet therapy (DAPT) with aspirin and a potent P2Y12 inhibitor is recommended for 12 months after drug-eluting stent (DES) implantation. Monotherapy with a potent P2Y12 inhibitor after short-term DAPT is an attractive option to better balance the risks of ischaemia and bleeding. Therefore, this study evaluated the efficacy and safety of ticagrelor monotherapy after short-term DAPT, especially in patients with ACS. METHODS: Electronic databases were searched from inception to 11 November 2023, and for the primary analysis, individual patient data were pooled from the relevant randomized clinical trials comparing ticagrelor monotherapy after short-term (≤3 months) DAPT with ticagrelor-based 12-month DAPT, exclusively in ACS patients undergoing DES implantation. The co-primary endpoints were ischaemic endpoint (composite of all-cause death, myocardial infarction, or stroke) and bleeding endpoint [Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding] at 1 year. RESULTS: Individual patient data from two randomized clinical trials including 5906 ACS patients were analysed. At 1 year, the primary ischaemic endpoint did not differ between the ticagrelor monotherapy and ticagrelor-based DAPT groups [1.9% vs. 2.5%; adjusted hazard ratio (HR) 0.79; 95% confidence interval (CI) 0.56-1.13; P = .194]. The incidence of the primary bleeding endpoint was lower in the ticagrelor monotherapy group (2.4% vs. 4.5%; adjusted HR 0.54; 95% CI 0.40-0.72; P < .001). The results were consistent in a secondary aggregate data meta-analysis including the ACS subgroup of additional randomized clinical trials which enrolled patients with ACS as well as chronic coronary syndrome. CONCLUSIONS: In ACS patients undergoing DES implantation, ticagrelor monotherapy after short-term DAPT was associated with less major bleeding without a concomitant increase in ischaemic events compared with ticagrelor-based 12-month DAPT. STUDY REGISTRATION: PROSPERO (ID: CRD42023476470).

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.

Coronary bypass surgery for multivessel disease after percutaneous coronary intervention in acute coronary syndromes: why, for whom, how early?

Multivessel coronary artery disease is present in ∼50% of patients with acute coronary syndrome and, compared with single-vessel disease, entails a higher risk of new ischaemic events and a worse prognosis. Randomized controlled trials have shown the superiority of 'complete revascularization' over culprit lesion-only treatment. Trials, however, only included patients treated with percutaneous coronary intervention (PCI), and evidence regarding complete revascularization with coronary artery bypass graft (CABG) surgery after culprit lesion-only PCI ('hybrid revascularization') is lacking. The CABG after PCI is an open, non-negligible therapeutic option, for patients with non-culprit left main and/or left anterior descending coronary artery disease where evidence in chronic coronary syndrome patients points in several cases to a preference of CABG over PCI. This valuable but poorly studied 'PCI first-CABG later' option presents, however, relevant challenges, mostly in the need of interrupting post-stenting dual antiplatelet therapy (DAPT) for surgery to prevent excess bleeding. Depending on patients' clinical characteristics and coronary anatomical features, either deferring surgery after a safe interruption of DAPT or bridging DAPT interruption with intravenous short-acting antithrombotic agents appears to be a suitable option. Off-pump minimally invasive surgical revascularization, associated with less operative bleeding than open-chest surgery, may be an adjunctive strategy when revascularization cannot be safely deferred and DAPT is not interrupted. Here, the rationale, patient selection, optimal timing, and adjunctive strategies are reviewed for an ideal approach to hybrid revascularization in post-acute coronary syndrome patients to support physicians' choices in a case-by-case patient-tailored approach.

Comparison of 3- to 6-Month Versus 12-Month Dual Antiplatelet Therapy After Coronary Intervention Using the Contemporary Drug-Eluting Stents With Ultrathin Struts: The HOST-IDEA Randomized Clinical Trial.

BACKGROUND: Limited data are available on short-term dual antiplatelet therapy (DAPT) after percutaneous coronary intervention using third-generation drug-eluting stents with ultrathin struts and advanced polymer technology. We investigated whether 3- to 6-month DAPT was noninferior to 12-month DAPT after implantation of drug-eluting stents with ultrathin struts and advanced polymer technology. METHODS: We performed an open-label, randomized trial at 37 centers in South Korea. We enrolled patients undergoing percutaneous coronary intervention using the Orsiro biodegradable-polymer sirolimus-eluting stents or the Coroflex ISAR polymer-free sirolimus-eluting stents. Patients with ST-segment-elevation myocardial infarction were excluded. Patients were randomly assigned to receive either 3- to 6-month or 12-month DAPT after percutaneous coronary intervention. The choice of antiplatelet medications was at the physician's discretion. The primary outcome was a net adverse clinical event, a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, stent thrombosis, or major bleeding, defined as Bleeding Academic Research Consortium type 3 or 5 at 12 months. The major secondary outcomes were target lesion failure, a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, and major bleeding. RESULTS: A total of 2013 patients (mean age, 65.7±10.5 years; 1487 males [73.9%]; 1110 [55.1%] presented with acute coronary syndrome) were randomly assigned to 3- to 6-month DAPT (n=1002) or 12-month DAPT (n=1011). The primary outcome occurred in 37 (3.7%) patients in the 3- to 6-month DAPT group and 41 (4.1%) in the 12-month DAPT group. The noninferiority of the 3- to 6-month DAPT group to the 12-month DAPT group was met (absolute risk difference, -0.4% [1-sided 95% CI, -∞% to 1.1%]; P<0.001 for noninferiority). There were no significant differences in target lesion failure (hazard ratio, 0.98 [95% CI, 0.56-1.71], P=0.94) or major bleeding (hazard ratio, 0.82 [95% CI, 0.41-1.61], P=0.56) between the 2 groups. Across various subgroups, the treatment effect of 3- to 6-month DAPT was consistent for net adverse clinical event. CONCLUSIONS: Among patients undergoing percutaneous coronary intervention using third-generation drug-eluting stents, 3- to 6-month DAPT was noninferior to 12-month DAPT for net adverse clinical event. Further research is needed to generalize this finding to other populations and to determine the ideal regimen for 3- to 6-month DAPT. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT02601157.

Indobufen or Aspirin on Top of Clopidogrel After Coronary Drug-Eluting Stent Implantation (OPTION): A Randomized, Open-Label, End Point-Blinded, Noninferiority Trial.

BACKGROUND: Dual antiplatelet therapy (DAPT) with aspirin as a background therapy has become the standard care after percutaneous coronary intervention. However, some adverse noncardiac effects limited the use of aspirin in clinical practice. Thus, evaluation of pharmacological alternatives to aspirin is attractive. Previous data indicated that indobufen could lessen the unwanted side effects of aspirin while retaining the antithrombotic efficacy, but its combination with a P2Y12 inhibitor still lacks randomized clinical trial evidence. METHODS: In this randomized, open-label, noninferiority trial, patients with negative cardiac troponin undergoing coronary drug-eluting stent implantation were randomly assigned in a 1:1 ratio to receive either indobufen-based DAPT (indobufen 100 mg twice a day plus clopidogrel 75 mg/d for 12 months) or conventional DAPT (aspirin 100 mg/d plus clopidogrel 75 mg/d for 12 months). The primary end point was a 1-year composite of cardiovascular death, nonfatal myocardial infarction, ischemic stroke, definite or probable stent thrombosis, or Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding. The end points were adjudicated by an independent Clinical Event Committee. RESULTS: Between January 11, 2018, and October 12, 2020, 4551 patients were randomized in 103 cardiovascular centers: 2258 patients to the indobufen-based DAPT group and 2293 to the conventional DAPT group. The primary end point occurred in 101 patients (4.47%) in the indobufen-based DAPT group and 140 patients (6.11%) in the conventional DAPT group (absolute difference, -1.63%; Pnoninferiority<0.001; hazard ratio, 0.73 [95% CI, 0.56-0.94]; P=0.015). Cardiovascular death, nonfatal myocardial infarction, ischemic stroke, and stent thrombosis were observed in 0.13%, 0.40%, 0.80%, and 0.22% of patients in the indobufen-based DAPT group and 0.17%, 0.44%, 0.83%, and 0.17% of patients in the conventional DAPT group (all P>0.05). The occurrence of Bleeding Academic Research Consortium criteria type 2, 3, or 5 bleeding events was lower in the indobufen-based DAPT group compared with the conventional DAPT group (2.97% versus 4.71%; hazard ratio, 0.63 [95% CI, 0.46-0.85]; P=0.002), with the main decrease in type 2 bleeding (1.68% versus 3.49%; hazard ratio, 0.48 [95% CI, 0.33-0.70]; P<0.001). CONCLUSIONS: In Chinese patients with negative cardiac troponin undergoing drug-eluting stent implantation, indobufen plus clopidogrel DAPT compared with aspirin plus clopidogrel DAPT significantly reduced the risk of 1-year net clinical outcomes, which was driven mainly by a reduction in bleeding events without an increase in ischemic events. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR-IIR-17013505.

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines.

AIM: The "2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease" provides an update to and consolidates new evidence since the "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease" and the corresponding "2014 ACC/AHA/AATS/PCNA/SCAI/STS Focused Update of the Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease." METHODS: A comprehensive literature search was conducted from September 2021 to May 2022. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. STRUCTURE: This guideline provides an evidenced-based and patient-centered approach to management of patients with chronic coronary disease, considering social determinants of health and incorporating the principles of shared decision-making and team-based care. Relevant topics include general approaches to treatment decisions, guideline-directed management and therapy to reduce symptoms and future cardiovascular events, decision-making pertaining to revascularization in patients with chronic coronary disease, recommendations for management in special populations, patient follow-up and monitoring, evidence gaps, and areas in need of future research. Where applicable, and based on availability of cost-effectiveness data, cost-value recommendations are also provided for clinicians. Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Real-world performance of indobufen versus aspirin after percutaneous coronary intervention: insights from the ASPIRATION registry.

BACKGROUND: Indobufen is widely used in patients with aspirin intolerance in East Asia. The OPTION trial launched by our cardiac center examined the performance of indobufen based dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI). However, the vast majority of patients with acute coronary syndrome (ACS) and aspirin intolerance were excluded. We aimed to explore this question in a real-world population. METHODS: Patients enrolled in the ASPIRATION registry were grouped according to the DAPT strategy that they received after PCI. The primary endpoints were major adverse cardiovascular and cerebrovascular events (MACCE) and Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding. Propensity score matching (PSM) was adopted for confounder adjustment. RESULTS: A total of 7135 patients were reviewed. After one-year follow-up, the indobufen group was associated with the same risk of MACCE versus the aspirin group after PSM (6.5% vs. 6.5%, hazard ratio [HR] = 0.99, 95% confidence interval [CI] = 0.65 to 1.52, P = 0.978). However, BARC type 2, 3, or 5 bleeding was significantly reduced (3.0% vs. 11.9%, HR = 0.24, 95% CI = 0.15 to 0.40, P < 0.001). These results were generally consistent across different subgroups including aspirin intolerance, except that indobufen appeared to increase the risk of MACCE in patients with ACS. CONCLUSIONS: Indobufen shared the same risk of MACCE but a lower risk of bleeding after PCI versus aspirin from a real-world perspective. Due to the observational nature of the current analysis, future studies are still warranted to further evaluate the efficacy of indobufen based DAPT, especially in patients with ACS. TRIAL REGISTRATION: Chinese Clinical Trial Register ( https://www.chictr.org.cn ); Number: ChiCTR2300067274.

Practice patterns of antiplatelet and anticoagulant therapy after fenestrated/branched endovascular aortic repair.

OBJECTIVE: Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR. METHODS: Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from 10 independent physician-sponsored investigational device exemption studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: (1) Aspirin alone OR P2Y12 alone (single-antiplatelet therapy [SAPT]); (2) Anticoagulant alone; (3) Aspirin + P2Y12 (dual-antiplatelet therapy [DAPT]); (4) Aspirin + anticoagulant OR P2Y12 + anticoagulant (SAPT + anticoagulant); (5) Aspirin + P2Y12 + anticoagulant (triple therapy [TT]); and (6) No therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention. RESULTS: Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT + anticoagulant, 3.2% on TT, 2.6% on anticoagulant alone, and 2.2% on no therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing with SAPT, DAPT conferred a lower hazard of loss of target artery patency (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.27-0.84; P = .01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (renal: HR, 0.66; 95% CI, 0.35-1.27; P = .22; visceral: HR, 0.31; 95% CI, 0.05-1.9; P = .21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency. CONCLUSIONS: Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an "optimal" regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.

Effects of Body Mass Index and Body Weight on Plasma Concentration of Ticagrelor and Platelet Aggregation Rate in Patients with Unstable Angina in a Chinese Han Population.

Background: The aim of this study was to investigate the impact of body mass index (BMI) and body weight on the concentrations of ticagrelor and the ticagrelor metabolite, AR-C124910XX, as well as the platelet aggregation rate (PAR) in a Chinese Han population with unstable angina (UA). Specifically, it focused on these parameters following the administration of dual antiplatelet therapy (DAPT) comprising aspirin and ticagrelor. Methods: A total of 105 patients with UA were included in the study. Measurement of the platelet aggregation rate induced by adenosine diphosphate (PAR-ADP) was performed before, as well as 3 and 30 days after DAPT treatment. The plasma concentrations of ticagrelor and AR-C124910XX were detected at 3 and 30 days after DAPT treatment. We conducted correlation analyses to assess the effects of BMI and body weight on the concentrations of ticagrelor and AR-C124910XX, on PAR-ADP, and on the inhibition of platelet aggregation induced by adenosine diphosphate (IPA-ADP) at both 3 and 30 days after DAPT treatment. Results: The BMI and body weight were positively correlated with baseline PAR-ADP (r = 0.205, p = 0.007; r = 0.122, p = 0.022). The PAR-ADP at 3 and 30 days after DAPT treatment were significantly lower than at baseline (61.56% ± 10.62%, 8.02% ± 7.52%, 12.90% ± 7.42%, p < 0.001). There was a negative correlation between body weight and the concentrations of ticagrelor and AR-C124910XX at 3 days following DAPT treatment (r = -0.276, p < 0.001; r = -0.337, p < 0.001). Additionally, BMI showed a similar negative correlation with the concentrations of ticagrelor and AR-C124910XX (r = -0.173, p = 0.009; r = -0.207, p = 0.002). At 30 days after treatment, both body weight and BMI were negatively correlated with ticagrelor (r = -0.256, p < 0.001; r = -0.162, p = 0.015) and its metabolite (r = -0.352, p < 0.001; r = -0.202, p = 0.002). Body weight was positively correlated with PAR-ADP (r = 0.171, p = 0.010) and negatively correlated with IPA-ADP (r = -0.163, p = 0.015) at 30 days after treatment. Similarly, BMI was positively correlated with PAR-ADP (r = 0.217, p = 0.001) and negatively correlated with IPA-ADP (r = -0.211, p = 0.001) at the same time point. Conclusions: BMI and body weight are key factors influencing the pharmacokinetics and pharmacodynamics of ticagrelor in Chinese Han patients with UA following DAPT treatment that includes ticagrelor. Both BMI and body weight were positively correlated with PAR-ADP at baseline and 30 days after DAPT treatment. Clinical Trial Registration: ChiCTR2100044938, https://www.chictr.org.cn/.

Comparison of thrombogenicity in different types of drug-eluting stents during transition from DAPT to SAPT.

BACKGROUND: During the transition from dual antiplatelet therapy (DAPT) to single antiplatelet therapy (SAPT), previous studies have raised concerns about a rebound effect. We compared platelet and inflammatory cell adhesion on different types of stents in the setting of clopidogrel presence and withdrawal. METHODS: In Experiment 1, three pigs were administered with DAPT, that is, clopidogrel and acetylsalicylic acid (ASA), for 7 days. Each animal underwent an extracorporeal carotid arteriovenous shunt model implanted with fluoropolymer-coated everolimus-eluting stent (FP-EES), biodegradable-polymer sirolimus-eluting stent (BP-SES), and biodegradable-polymer everolimus-eluting stents (BP-EES). In Experiment 2, two pigs were administered DAPT, clopidogrel was then withdrawn at day 7, and SAPT with ASA was continued for next 21 days. Then flow-loop experiments with the drawn blood from each time point were performed for FP-EES, BioLinx-polymer zotarolimus-eluting stents (BL-ZES), and BP-EES. The rebound effect was defined as the statistical increase of inflammation and platelet adhesion assessed with immunohistochemistry on the stent-strut level basis from baseline to day-14 or 28. RESULTS: Both experiments showed platelet adhesion value was highest in BP-EES, while the least in FP-EES during DAPT therapy. There was no increase in platelet or inflammatory cell adhesion above baseline values (i.e., no therapy) due to the cessation of clopidogrel on the stent-strut level. Monocyte adhesion was the least for FP-EES with the same trend observed for neutrophil adhesion. CONCLUSIONS: No evidence of rebound effect was seen after the transition from DAPT to SAPT. FP-EES demonstrated the most favorable antithrombotic and anti-inflammatory profile regardless of the different experimental designs.

Novel insights on dual antiplatelet therapy duration following stenting for angiography-detected moderate-to-severe calcified coronary lesions.

Dual antiplatelet therapy (DAPT), comprising both aspirin and the P2Y12 receptor inhibitor, is crucial in managing patients with coronary artery disease following percutaneous coronary intervention (PCI). The optimal duration for DAPT in patients with angiography-detected moderate-to-severe calcified coronary (MSCC) lesions who underwent PCI with drug-eluting stents (DES) implantation remains uncertain. We recruited patients with angiography-detected MSCC lesions who received DES implantation from the prospective Fuwai Percutaneous Coronary Intervention Registry. Patients were classified into two groups according to the duration of DAPT: those with a DAPT duration of one year or less, and those with a DAPT duration of more than one year. The primary endpoint was the major adverse cardiovascular and cerebrovascular event, which was defined as composed of all-cause death, nonfatal myocardial infarction, or nonfatal stroke. The key-safety endpoint was bleeding type 2, 3, or 5 according to the Bleeding Academic Research Consortium criteria. There were 1730 patients included in the study, and 470 (27.17 %) continued DAPT for more than one year after undergoing MSCC-PCI with DES implantation. The median follow-up time was 2.5 years. DAPT>1-year versus ≤1-year DAPT was significantly associated with a reduced risk of the primary outcome (1.59 % versus 3.19 %; adjusted hazard ratio=0.44; 95 % CI: 0.22-0.88). Similar trends were observed for all-cause death (0.16 % versus 1.91 %; P<0.001) and cardiovascular death (0.08 % versus 1.06 %; P=0.001). There was no significant difference in the key-safety endpoint between 2 regimens (1.75 % versus 0.85 %; adjusted hazard ratio=1.95; 95 % CI: 0.65-5.84). In conclusion, long-term DAPT after DES implantation in patients with MSCC lesions resulted in improved clinical outcomes at 2.5 years. This was achieved by reducing the risk of ischemia without increasing clinically significant bleeding.

Clopidogrel with indobufen or aspirin in minor ischemic stroke or high-risk transient ischemic attack: a randomized controlled clinical study.

BACKGROUND: Ischemic stroke and transient ischemic attack (TIA) are the most prevalent cerebrovascular diseases. The conventional antiplatelet drugs are associated with an inherent bleeding risk, while indobufen is a new antiplatelet drug and has the similar mechanism of antiplatelet aggregation as aspirin with more safety profile. However, there have been no studies evaluating the combination therapy of indobufen and clopidogrel for antiplatelet therapy in cerebrovascular diseases. OBJECTIVE: The CARMIA study aims to investigate the effectiveness and safety of a new dual antiplatelet therapy consisting of indobufen and clopidogrel comparing with the conventional dual antiplatelet therapy consisting of aspirin and clopidogrel in patients with minor ischemic stroke or high-risk TIA. METHODS: An open-label randomized controlled clinical trial was conducted at a clinical center. We randomly assigned patients who had experienced a minor stroke or transient ischemic attack (TIA) within 72 h of onset, or within 1 month if they had intracranial stenosis (IS), to receive either indobufen 100 mg twice daily or aspirin 100 mg once daily for 21 days. For patients with IS, the treatment duration was extended to 3 months. All patients received a loading dose of 300 mg clopidogrel orally on the first day, followed by 75 mg once daily from the second day to 1 year. We collected prospective data using paper-based case report forms, and followed up on enrolled patients was conducted to assess the incidence of recurrent ischemic stroke or TIA, mRS score, NIHSS (National Institutes of Health Stroke Scale) score, and any bleeding events occurring within 3 month after onset. RESULTS: We enrolled 202 patients diagnosed with ischemic stroke or transient ischemic attack. After applying the criteria, 182 patients were eligible for data analysis. Endpoint events (recurrence of ischemic stroke/TIA, myocardial infarction, or death) were observed in 6 patients (6.5%) receiving aspirin and clopidogrel, including 4 (4.3%) with stroke recurrence, 1 (1.1%) with TIA recurrence, and 1 (1%) with death. In contrast, no endpoint events were reported in the indobufen and clopidogrel group (P = 0.029). The group of patients receiving indobufen and clopidogrel exhibited significantly lower modified Rankin Scale (mRS) score. (scores range from 0 to 6, with higher scores indicating more severe disability) compared to the aspirin and clopidogrel group (common odds ratio 3.629, 95% CI 1.874-7.036, P < 0.0001). Although the improvement rate of NIHSS score in the indobufen and clopidogrel group was higher than that in the aspirin and clopidogrel group, the difference was not statistically significant (P > 0.05). Bleeding events were observed in 8 patients (8.6%) receiving aspirin and clopidogrel, including 4 (4.3%) with skin bleeding, 2 (2.2%) with gingival bleeding, 1 (1.1%) with gastrointestinal bleeding, and 1 (1.1%) with urinary system bleeding. On the other hand, only 1 patient (1.1%) in the indobufen and clopidogrel group experienced skin bleeding (P = 0.035). CONCLUSION: The combination of indobufen and clopidogrel has shown non-inferior and potentially superior effectiveness and safety compared to aspirin combined with clopidogrel in patients with minor ischemic stroke and high-risk TIA in the CARMIA study (registered under chictr.org.cn with registration number ChiCTR2100043087 in 01/02/2021).

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

BACKGROUND: The safety and feasibility of using 1-month dual antiplatelet therapy (DAPT) followed by P2Y12inhibitor monotherapy for patients after percutaneous coronary intervention (PCI) with thin-strut biodegradable polymer drug-eluting stents (BP-DES) in daily clinical practice remain uncertain. METHODS AND RESULTS: The REIWA region-wide registry is a prospective study conducted in 1 PCI center and 9 local hospitals in northern Japan. A total of 1,202 patients who successfully underwent final PCI using BP-DES (Synergy: n=400; Ultimaster: n=401; Orsiro: n=401), were enrolled in the registry, and received 1-month DAPT followed by P2Y12inhibitor (prasugrel 3.75 mg/day or clopidogrel 75 mg/day) monotherapy. The primary endpoint was a composite of cardiovascular and bleeding events at 12 months, including cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST), ischemic or hemorrhagic stroke, and Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding. Based on the results of a previous study, we set the performance goal at 5.0%. Over the 1-year follow-up, the primary endpoint occurred in 3.08% of patients, which was lower than the predefined performance goal (Pnon-inferiority<0.0001). Notably, definite ST occurred in only 1 patient (0.08%) within 1 year (at 258 days). No differences were observed in the primary endpoint between stent types. CONCLUSIONS: The REIWA region-wide registry suggests that 1-month DAPT followed by P2Y12inhibitor monotherapy is safe and feasible for Japanese patients with BP-DES.

Renal Function-Stratified Comparison of Short- and Long-Term Dual Antiplatelet Therapy in Patients Undergoing Percutaneous Coronary Intervention With Third-Generation Drug-Eluting Stents　- Post Hoc Analysis From the HOST-IDEA Randomized Clinical Trial.

BACKGROUND: The optimal duration of dual antiplatelet therapy (DAPT) in patients with chronic kidney disease undergoing percutaneous coronary intervention (PCI), especially with third-generation drug-eluting stents (DES), remains unknown. METHODS AND RESULTS: We conducted a prespecified post hoc analysis of the HOST-IDEA trial, randomizing patients undergoing PCI with third-generation DES to 3- to 6-month or 12-month DAPT. In all, 1,997 patients were grouped by their estimated glomerular filtration rate (eGFR): high (>90 mL/min/1.73 m2), intermediate (60-90 mL/min/1.73 m2), and low (<60 mL/min/1.73 m2). The primary outcome was net adverse clinical events (NACE), a composite of cardiac death, target vessel myocardial infarction, clinically driven target lesion revascularization, stent thrombosis, or major bleeding (Bleeding Academic Research Consortium Type 3 or 5) at 12 months. Secondary outcomes were target lesion failure (TLF) and major bleeding. The low eGFR group had the highest rates of NACE, TLF, and major bleeding compared with the other 2 groups (P<0.001). Rates of NACE were similar in the 3- to 6-month and 12-month DAPT in the high (2.9% vs. 3.2%; P=0.84), intermediate (2.1% vs. 2.8%, P=0.51), and low (8.9% vs. 9.1%; hazard ratio 0.99; P=0.97; Pinteraction=0.88) eGFR groups. TLF and major bleeding events showed similar trends. CONCLUSIONS: In patients undergoing PCI with third-generation DES, 3- to 6-month DAPT was comparable to 12-month DAPT for clinical outcomes regardless of renal function.

Subacute in-stent thrombosis after carotid artery stenting in a patient with gene polymorphisms associated with aspirin and clopidogrel resistance: a case report.

BACKGROUND: Carotid artery stenting (CAS) is a key treatment option for moderate to severe carotid artery stenosis. Carotid stent thrombosis (CST), a rare complication of CAS, has gained significant attention because of its catastrophic nature. More evidences are needed to guide the diagnosis and treatment of CST. CASE PRESENTATION: This study reports a rare case of sub-acute CST following CAS in a 50-year-old male patient who had experienced repeated cerebrovascular events on the premise of taking antiplatelet drugs. He also suffered an occlusion of the left middle cerebral artery (MCA) in the M2 segment, likely caused by an embolus detached from the stent thrombus. The cause of CST in this patient was presumed to be dual antiplatelet resistance (AR), as indicated by genetic testing. After treated with guide catheter-directed thrombolysis, thrombus aspiration, and a second round of thrombolysis, his in-stent thrombus was basically cleared. His M2 occlusion was resolved by mechanical thrombectomy using the Solitaire FR/Stent with Intermediate Catheter Assisting technique. The patient recovered well after replacement of antiplatelet drugs, and no new thromboembolic event occurred during the 13-month follow-up period. CONCLUSIONS: The occurrence rate of AR-related CST may be underestimated as the cause of majority CST cases remains unclear. Implementation of genetic test for aspirin and clopidogrel resistance may be helpful to find the possible cause of CST and to avoid future repeated cerebrovascular events by replacement of antiplatelet drugs.

Discharge of Acute Coronary Syndrome Patients on Sub-Optimal Dual Anti-Platelet Therapy: A Single Center Experience.

PURPOSE: To identify and quantify the reasons why acute coronary syndrome (ACS) patients undergoing stenting at the University of New Mexico Hospital (UNMH) were prescribed sub-optimal dual antiplatelet therapy (DAPT) at discharge, and to identify practice patterns that could potentially lead to improved DAPT treatment for these patients. METHODS: We reviewed electronic medical records and cardiac catheterization records of 326 patients who underwent percutaneous coronary intervention (PCI) at UNMH between January 1, 2021, and June 30, 2022 and identified 229 ACS patients who survived until discharge. Demographic and clinical characteristics relevant to P2Y12 inhibitor selection were obtained from a review of medical records. Pharmacists' notes documenting their efforts to secure appropriate insurance coverage and reasons for discharging patients on clopidogrel rather than ticagrelor/prasugrel were reviewed. Patients discharged on aspirin and clopidogrel underwent review of medical records and cardiac catheterization lab records to determine if the discharge P2Y12 drug was appropriate. Reasons for inappropriate discharge on clopidogrel were categorized as cost/insurance, patient preference, concern for daily adherence to a twice-daily medication, and maintenance of pre-hospital clopidogrel therapy rather than switch to ticagrelor after PCI. RESULTS: The 229 ACS patients included 87 (38.0%) appropriately discharged on ticagrelor/prasugrel, 63 (27.5%) appropriately discharged on clopidogrel, 75 (32.8%) discharged on sub-optimal clopidogrel, and 4 (1.7%) not discharged on a P2Y12 inhibitor. For patients inappropriately discharged on clopidogrel (n = 75), the most common reasons were cost or lack of insurance (n = 56) and clinical inertia (taking clopidogrel before PCI and maintained on it afterward) (n = 17). Sub-optimal P2Y12 therapy at discharge was significantly associated with lack of insurance (odds ratio 21.5, 95% confidence interval 5.33-156,p < 0.001) but not with ethnicity, age, sex, or diabetes. CONCLUSION: At the University of New Mexico, a safety-net hospital, increasing financially restricted access to ticagrelor/prasugrel could help up to 24.5% of ACS patients reduce their risk of ischemic events. For patients admitted on clopidogrel DAPT, escalating to ticagrelor/prasugrel could reduce ischemic risk in 7.4%. Expanding and improving healthcare insurance coverage might reduce the frequency of discharge on sub-optimal P2Y12 therapy.

Randomized evaluation of 5-month Ticagrelor monotherapy after 1-month dual-antiplatelet therapy in patients with acute coronary syndrome treated with drug-coated balloons: REC-CAGEFREE II trial rationale and design.

BACKGROUND: Patients treated with drug-coated balloons (DCB) have the theoretical advantage of adopting a low-intensity antiplatelet regimen due to the absence of struts and polymers. Nevertheless, the optimal antiplatelet strategy for patients undergoing DCB-only treatment remains a topic of debate and has not been investigated in randomized trials. METHODS: The REC-CAGEFREE II is an investigator-initiated, prospective, open-label, multi-center, randomized, non-inferiority trial aimed to enroll 1908 patients from ≥ 40 interventional cardiology centers in China to evaluate the non-inferiority of an antiplatelet regimen consisting of Aspirin plus Ticagrelor for one month, followed by five months Ticagrelor monotherapy, and then Aspirin monotherapy for six months (Experimental group) compared to the conventional treatment of Aspirin plus Ticagrelor for 12 months (Reference group) in patients with acute coronary syndrome (ACS) who have undergone percutaneous coronary intervention (PCI) using paclitaxel-coated balloons (DCB) exclusively. Participants will be randomly assigned to the Experimental or Reference group in a 1:1 ratio. The randomization will be stratified based on the center and the type of lesion being treated (De novo or in-stent restenosis). The primary endpoint is net adverse clinical events (NACE) within 12 months of PCI, which includes the composite of all-cause death, any stroke, any myocardial infarction, any revascularization and Bleeding Academic Research Consortium (BARC) defined type 3 or 5 bleeding. The secondary endpoint, any ischemic and bleeding event, which includes all-cause death, any stroke, MI, BARC-defined type 3 bleeding, any revascularization, and BARC-defined type 2 bleeding events, will be treated as having hierarchical clinical importance in the above order and analyzed using the win ratio method. DISCUSSION: The ongoing REC-CAGEFREE II trial aims to assess the efficacy and safety of a low-intensity antiplatelet approach among ACS patients with DCB. If non-inferiority is shown, the novel antiplatelet approach could provide an alternative treatment for ACS patients with DCB. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04971356.