The antiplatelet effect of prasugrel for acute ischemic stroke or transient ischemic attack (TIA) remains unclear. This study compared platelet reactivity between prasugrel and clopidogrel, considering cytochrome P450 family 2 subfamily C member 19 (CYP2C19) gene polymorphisms (extensive metabolizers [EM], intermediate metabolizers [IM], and poor metabolizers [PM]), in patients with acute large artery atherosclerosis (LAA) or high-risk TIA.

In this multicenter open-label randomized controlled study, patients with acute LAA or high-risk TIA received prasugrel or clopidogrel with aspirin. The primary endpoint was platelet reaction units (PRU) 5 days after the start of drug administration, stratified according to CYP2C19 polymorphism. In all, 176 patients participated (88 in each group). Compared with the clopidogrel group, PRU on Day 5 in the prasugrel group were significantly lower in the overall population (adjusted mean 136.0 vs. 169.9; estimated difference -33.9; 95% confidence interval [CI] -49.0, -18.8), EM group (118.5 vs. 144.8; estimated difference -26.2; 95% CI -48.0, -4.4), and IM group (140.3 vs. 173.1; estimated difference -32.8; 95% CI -56.6, -9.0), and tended to be lower in the PM group (164.7 vs. 196.2; estimated difference -31.6; 95% CI -68.3, 5.1). The prevalence of new infarct lesions was comparable between the prasugrel and clopidogrel groups, as was the incidence of adverse events (30.7% vs. 26.1%, respectively) and bleeding events up to Day 5 of administration.

In patients with acute LAA or high-risk TIA, prasugrel resulted in stable inhibition of platelet aggregation 5 days after starting drug administration compared with clopidogrel, regardless of CYP2C19 polymorphisms.

Clopidogrel, an anti-platelet drug, is used to prevent thrombosis after percutaneous coronary intervention. Clopidogrel resistance results in recurring ischemic events, with African Americans (AA) suffering disproportionately. The aim of this study was to discover novel biomarkers of clopidogrel resistance in African Americans using genome and transcriptome data. We conducted a genome-wide association study (GWAS), including local ancestry adjustment, in 141 AA on clopidogrel to identify genetic associations with high on-treatment platelet reactivity (HTPR), with validation of genome-wide significant and suggestive loci in an independent cohort of AA clopidogrel patients (N = 823) from the Million Veteran's Program (MVP) along with in vitro functional analysis. We performed differential gene expression (DGE) analysis in whole blood to identify transcriptomic predictors of response, followed by functional validation in MEG-01 cells. GWAS identified one signal on Chromosome 7 as significantly associated with increasing risk of HTPR. The lead single-nucleotide polymorphism (SNP), rs7807369, within thrombospondin 7A (THSD7A) was associated with an increased risk of HTPR (odds ratio (OR) = 4.02, P = 4.56 × 10-9). Higher THSD7A gene expression was associated with HTPR in an independent cohort of clopidogrel-treated patients (P = 0.004) and carrying a risk allele showed increased gene expression in primary human endothelial cells. Notably, the CYP2C19*2 variants showed no association with clopidogrel response in the discovery or MVP cohorts. DGE analysis identified an association with decreased LAIR1 and AP3B2 expression to HTPR. LAIR1 knockdown in MEG-01 cells resulted in increased expression of SYK and AKT1, suggesting an inhibitory role of LAIR1 in the Glycoprotein VI pathway. In summary, these findings suggest that other variants and genes outside of CYP2C19 star alleles play an important role in clopidogrel response in AA.

Patients with high on-treatment platelet reactivity (HTPR) undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) face increased risks of major adverse cardiovascular events (MACEs). Although platelet function tests like thrombelastography (TEG), vasodilator-stimulated phosphoprotein (VASP), PL-11, and VerifyNow have been described, the correlation between them and their prognostic implications remains uncertain. This prospective study aims to evaluate the consistency and effectiveness of four platelet function detection methods in predicting long-term MACEs in patients with ACS. All 98 ACS patients undergoing PCI with clopidogrel were assessed for HTPR using four platelet function detection methods. The endpoint was the occurrence of MACEs, including cardiac death, nonfatal myocardial infarction (MI), and target vessel revascularization (TVR). Among 98 patients enrolled from April 1, 2014 to June 30, 2014, 27 (27.6%) patients with VerifyNow-detected HTPR (P2Y12 reaction units [PRUs] >240). The incidence of HTPR was 58.2% for TEG, 52% for VASP, and 13.3% for PL-11. VerifyNow and TEG showed the highest consistency in detecting HTPR (kappa = 0.201, p = 0.015). During a median follow-up of 6.1 years, 29 MACEs occurred, including 24 TVRs, 3 cardiovascular deaths, and 2 nonfatal MIs. VerifyNow-detected HTPR independently predicted long-term MACEs (hazard ratio: 5.73, 95% confidence interval: 2.04-16.09, p = 0.001), even after adjusting for traditional risk factors (TRFs). Receiver operating characteristic (ROC) analysis indicated that the model incorporating TRFs and VerifyNow-detected HTPR had superior predictive discrimination for MACEs (area under ROC curve = 0.889). VerifyNow-detected HTPR independently emerges as a robust predictor for long-term MACEs, demonstrating superior predictive discrimination compared with other platelet function tests.

The P2Y12 receptor inhibitor prasugrel was approved for thrombotic stroke in Japan following the phase 3 clinical trials PRASTRO-I, -II, and -III. However, correlations between elevated platelet reaction unit (PRU) and ischemic event risk remain unclear. This post hoc integrated analysis of PRASTRO-I, -II, and -III assessed the relationships of PRU with efficacy and safety outcomes, and risk factors for high PRU (HPR). Patients from PRASTRO-I, -II, and -III receiving prasugrel or clopidogrel and with PRU values at 4 and 24 weeks after treatment initiation were included. The primary endpoint was PRU at 4 weeks; secondary endpoints included cumulative incidence of ischemic and bleeding events from study drug initiation to 48 weeks. Exploratory univariate and multivariate analyses were conducted to identify HPR risk factors. Of 2688 patients analyzed, 2595 and 2434 had PRU values available at 4 and 24 weeks, respectively. Mean PRU was numerically lower with prasugrel than clopidogrel at 4 weeks (151.3 vs. 195.4) and 24 weeks (143.8 vs. 188.0). CYP2C19 polymorphisms affected PRU at 4 and 24 weeks with clopidogrel but not with prasugrel. PRU at 4 weeks did not predict ischemic and bleeding event incidence up to 48 weeks. The CYP2C19 poor metabolizer phenotype was the strongest HPR risk factor. PRU values at 4 and 24 weeks were numerically lower with prasugrel and unaffected by CYP2C19 genetic polymorphisms. Further research is needed to clarify the relationship of PRU with ischemic and bleeding events.

While platelet hyperreactivity constitutes an independent risk factor for major adverse cardiovascular events (MACEs) in coronary artery disease, its molecular underpinnings remain poorly characterized. Recent advances in transcriptomic profiling have revealed potential associations with specific RNA signatures. Through systematic bioinformatics analysis of differential gene expression patterns and pathway activation in CHD patients, this study aims to elucidate key molecular regulators of platelet hyperactivity, establishing a theoretical framework for developing precision therapeutic strategies to mitigate post-CHD complications.

This randomized controlled study included 16 CHD patients and 16 healthy controls. Inflammation markers, platelet aggregation function, and CD62p levels were assessed using flow cytometry. Mitochondrial morphology and organelles were observed using scanning electron microscopy and transmission electron microscopy. Genes related to symptom alteration between CHD patients and healthy controls were identified using the criteria of p < 0.05. The molecular correlations of these genes were analyzed using a comprehensive perspective that included Gene Ontology (GO) biological process and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Western blot and correlation analyses were also conducted to validate the expression and diagnostic value of the DEGs.

CHD patients exhibited alterations in platelet organelles ultrastructure, heightened platelet activation and aggregation, and disturbance of the inflammatory equilibrium. RNA sequencing demonstrated distinct changes in the gene expression profiles of circulating platelets from CHD patients. The increase in platelet activation and aggregation could be partially associated with the upregulation of the Talin-1 and αIIbβ3 proteins expression.

Abnormal transcription and platelet activation occur after CHD onset, and upregulation of the Talin-1/αIIbβ3-mediated bidirectional signaling pathway are the primary pathological features.

https://www.chictr.org.cn/, identifier ChiCTR2100041998.

Bleeding avoidance strategies are critical in the modern era of percutaneous coronary intervention; however, most efforts are geared toward reducing access-related complications. Improvements in procedural techniques (radial access, improved procedural anticoagulation regimens, etc) and modifications in postdischarge pharmacotherapy (shortened dual antiplatelet therapy, genotype-guided P2Y12 inhibition, etc) that led to a decline in bleeding related to percutaneous procedures were largely offset by increases in complexity and performance of percutaneous coronary intervention in high-risk patients. Among patients presenting with acute coronary syndrome, aggressive antiplatelet regimens with potent P2Y12 inhibitors are typically prescribed for a longer duration, prioritizing reduction in ischemic events over bleeding risk. Because postdischarge bleeding connotes an adverse prognosis similar to an ischemic event, postprocedure freedom from adverse outcomes can be best tailored by individualizing and recognizing the patient's bleeding and ischemic risks. This review of the contemporary and historical literature (PubMed, EMBASE, Cochrane Library) summarizes the available data, provides strategies to navigate these complex decisions, and helps individualize antithrombotic therapy.

Recent studies have highlighted the complexity of platelet biology, revealing their diverse roles beyond hemostasis. Pathological platelet activation is now recognized as a key contributor to thrombosis and inflammation that are both central to cardiovascular disease (CVD). Emerging research emphasizes the significant impact of demographic factors - such as age, sex, race, and ethnicity - on CVD risk and responses to antiplatelet therapies. These population-based differences, shaped by genetic and non-genetic factors, highlight the need for reevaluation of antiplatelet strategies. We address current knowledge and emphasize the pressing need for further research into platelet biology and cardiovascular outcomes across diverse populations. In this review we advocate for tailored therapeutic approaches in CVD based on the recent demographic-focused findings.

Antiplatelet therapy is crucial for reducing thrombotic events in patients with atherosclerotic disease, but the response vary widely among individuals. The identification of patients at high (HPR), optimal (OPR) or low platelet reactivity (LPR) is dependent on high interlaboratory variability. We report results of a large dataset of patients to assess the gold standard light transmission aggregometry (LTA). A total of 11,913 patients who sequentially underwent LTA assessment using several stimuli (ADP-2µM, collagen-2 µg/ml, arachidonic acid 0.5 mM, epinephrine 10µM) with a standardized methodology between 2004 and 2022 were screened. After application of inclusion-exclusion criteria, 5,901 patients were included and divided into five groups: healthy-volunteers (HV; N = 534); controls (CTR; N = 1073); aspirin-treated patients (ASA; 75-150 mg/die; N = 3280); clopidogrel-treated patients (CLOP; 75 mg/die; N = 495) and patients treated with dual antiplatelet therapy, ASA plus CLOP (DAPT; N = 519). The mean PA% in response to ADP 2 μm was 72.4 ± 33.3 in the CTR population, 40.6 ± 29.9 in the ASA group, 25.1 ± 35.1 in the CLOP group and 10.2 ± 18.5 in the DAPT group. The mean PA% in response to collagen 2 ug/ml was 90.7 ± 10.5 in the CTR population, 40.8 ± 26.3 in the ASA group, 79.4 ± 21.8 in the CLOP group and 17.9 ± 19.9 in the DAPT group. The percentage of patients at OPR following ADP stimuli was 66%, 25%, and 26%, in the ASA, CLOP, and DAPT group, respectively. The percentage of patients at OPR following collagen stimuli was 56%, 22%, and 41%, in the ASA, CLOP, and DAPT group, respectively. LTA was significantly increased in response to ADP (72.4 ± 33.3vs62.7 ± 37.1; p < 0.001) and AA (90.7 ± 15.6vs87.6 ± 20.5; p < 0.001) in CTR compared to HV. Our findings support the concept that a significant proportion of individuals present a hyper- or hypo-reactive platelet phenotype potentially affecting the safety and efficacy of antiplatelet therapy. The variability in response to antiplatelet therapy was particularly evident in patients undergoing single as opposed to dual antiplatelet therapy regimens. These data support ongoing strategies of guided selection of antiplatelet therapy in patients with cardiovascular disease.

Investigations of very long-term outcomes after percutaneous coronary intervention (PCI) with drug-eluting stents (DES) according to clinical presentation are scarce. Here, we investigated the 10-year clinical outcomes of patients undergoing DES-PCI according to clinical presentation.

Patient-level data from five randomized trials with 10-year follow-up after DES-PCI were pooled. Patients were dichotomized into acute coronary syndrome (ACS) or chronic coronary syndrome (CCS) groups as per clinical presentation. The primary outcome was all-cause death. Secondary outcomes were cardiovascular death, myocardial infarction (MI), definite stent thrombosis (ST) and repeat revascularization involving the target lesion (TLR), target vessel (TVR) or non-target vessel (nTVR).

Of the 9700 patients included in this analysis, 4557 presented with ACS and 5143 with CCS. Compared with CCS patients, ACS patients had a higher risk of all-cause death and nTVR in the first year, but comparable risk thereafter. In addition, ACS patients had a higher risk of MI [adjusted hazard ratio 1.21, 95% confidence interval (1.04-1.41)] and definite ST [adjusted hazard ratio 1.48, 95% confidence interval (1.14-1.92)], while the risk of TLR and TVR was not significantly different up to 10-year follow-up.

Compared to CCS patients, ACS patients treated with PCI and DES implantation have an increased risk of all-cause death and repeat revascularization of remote vessels up to 1 year, with no significant differences thereafter and up to 10-year follow-up. ACS patients have a consistently higher risk of MI and definite ST. Whether these differences persist with current antithrombotic and secondary prevention therapies requires further investigation.

The optimal low-dose antiplatelet agents in patients with coronary heart disease (CHD) had not been determined. The objective of this study was to compare the impact of different low-dose antiplatelet agents on cardiovascular outcomes and bleeding risks in patients with CHD.

We searched PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure, VIP, WanFang Data, and China Biology Medicine. Randomized controlled trials (RCTs) enrolling patients with CHD treated with different low-dose platelet aggregation inhibitors were included. The revised Cochrane Risk of Bias Tool for Randomized Trials Risk was used to assess risk of bias in RCTs. A Bayesian random network meta-analysis (NMA) was conducted, with odds ratios (OR) and 95% confidence intervals (CI) as effect estimates in R 4.2.2 software and Stata 15.0. The quality of evidence was assessed using the Confidence in NMA framework.

Sixteen RCTs involving 6350 patients were included. All participants were treated with a recommended dose of aspirin plus a low or standard dose of P2Y12 receptor antagonist. Low-level evidence indicated the risk of major adverse cardiovascular events (MACE) was similar among low doses of prasugrel, ticagrelor, standard doses of prasugrel, ticagrelor, and clopidogrel. Low- to moderate-level evidence suggested there was no difference in bleeding risk among low dose of prasugrel, ticagrelor, clopidogrel compared to standard dose of prasugrel, ticagrelor, and clopidogrel. NMA showed that low dose of prasugrel had the highest probability of being the best intervention in terms of MACE, myocardial infarction, and bleeding events leading to discontinuation.

Based on low-level evidence, low dose of prasugrel combined with standard dose of aspirin can be recommended for patients with CHD, low dose of ticagrelor was similar in terms of MACE and bleeding compared with standard dose of P2Y12 receptor antagonist. The systematic review was registered in PROSPERO with the registration number CRD42023438376.

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

Background: Patients with a HeartMate 3 (HM3) left ventricular assist device (LVAD) typically receive anticoagulation and antiplatelet therapy. The HM3 has shown a marked reduction in hemocompatibility-related adverse events (HRAEs) like stroke, bleeding, and pump thrombosis. This study evaluated whether aspirin (ASA) response influences HRAE incidence and if ASA sensitivity changes over time in HM3 recipients. Methods: This single-center, cross-sectional study included 32 HM3 patients (age: 59.0 ± 10.0 years, 15.6% female). ASA sensitivity was assessed twice using the VerifyNow assay, with ASA resistance defined by ASA reactivity units (ARU) > 550. The primary endpoint was HRAE incidence in ASA responders vs. non-responders over two consecutive follow-ups; the secondary endpoint was temporal changes in ASA resistance. Results: At the first follow-up, 13 (40.6%) patients were ASA-resistant, and 8 (28.6%) were resistant at the second follow-up, without significant change (p = 0.22). ASA non-responders and responders had similar ASA doses and baseline characteristics. No significant difference in HRAE incidence was found between ASA non-responders and responders (0.0% vs. 15.8%, p = 0.14), and no additional HRAEs occurred during follow-up. Conclusions: ASA resistance varied considerably among HM3 patients without significant temporal changes, and the demonstrated excellent hemocompatibility supports recent evidence that ASA may have a limited role in the antithrombotic regimen for HM3 recipients.

Current evidence indicates that dual antiplatelet therapy with aspirin plus a P2Y12 inhibitor is essential for the prevention of thrombotic events after percutaneous coronary interventions. However, dual antiplatelet therapy is associated with increased bleeding which may outweigh the benefits. This has set the foundations for customizing antiplatelet treatments to the individual patient. However, bleeding and ischemic risks are often present in the same patient, making it difficult to achieve this balance. The fact that oral P2Y12 inhibitors (clopidogrel, prasugrel, and ticagrelor) have diverse pharmacodynamic profiles that affect clinical outcomes supports the rationale for using platelet function and genetic testing to individualize antiplatelet treatment regimens. Indeed, up to one-third of patients treated with clopidogrel, but a minority of those treated with prasugrel or ticagrelor, exhibit high residual platelet reactivity resulting in an increased thrombotic risk. On the other hand, prasugrel and ticagrelor are frequently associated with low platelet reactivity and increased bleeding risk compared with clopidogrel without providing any additional reduction in ischemic events compared with patients who adequately respond to clopidogrel. The use of platelet function and genetic testing may allow for a guided selection of oral P2Y12 inhibitors. However, the nonuniform results of randomized controlled trials have led guidelines to provide limited recommendations on the implementation of these tests in patients undergoing percutaneous coronary intervention. In light of recent advancements in the field, this consensus document by a panel of international experts fills in the guideline gap by providing updates on the latest evidence in the field as well as recommendations for clinical practice.

Resistance to dual antiplatelet therapy (DAPT), including aspirin and clopidogrel, in patients who have undergone percutaneous coronary intervention (PCI) leads to the inability to prevent thrombotic complications. The present study aimed to evaluate early resistance to aspirin and clopidogrel in patients following PCI using the VerifyNow test and associated factors. A total of 50 patients diagnosed with acute coronary syndromes (ACS) who underwent emergency PCI and received DAPT were recruited in the present study. The detection of resistance to aspirin and clopidogrel was performed using the VerifyNow system. Resistance to aspirin was determined with VerifyNow Aspirin >550 aspirin reaction units (ARU). Resistance to clopidogrel was determined with VerifyNow P2Y12 >208 P2Y12 reaction units (PRU). The resistance rate to aspirin was 14%, while the resistance rate to clopidogrel was higher, at 34%. There were 2 patients with resistance to aspirin and clopidogrel (4%). Univariable logistic regression analysis revealed that diabetes, the use of β-blockers, and low levels of hemoglobin and hematocrit were associated with resistance to clopidogrel. Following multivariable logistic regression analysis, only the use of β-blockers was truly associated with resistance to clopidogrel. On the whole, the results of the present study may also prove to be helpful in the selection of therapeutic drugs for patients undergoing PCI and who are diagnosed with ACS.

Carriers of cytochrome 2C19 (CYP2C19) loss-of-function (LoF) alleles treated with clopidogrel have impaired drug metabolism, resulting in reduced active metabolite levels, high platelet reactivity (HPR), and an increased risk of thrombotic events. Several alternative antiplatelet therapies have been proposed to overcome HPR in these patients, but their comparative effects remain poorly explored.

Randomized controlled trials (RCTs) comparing different oral antiplatelet therapies in carriers of CYP2C19 LoF alleles undergoing percutaneous coronary interventions (PCI) were included. A frequentist network meta-analysis was conducted to estimate mean difference (MD) or odds ratios and 95% confidence intervals (CI). The primary outcome was platelet reactivity assessed by VerifyNow and reported as P2Y12 reaction unit (PRU). The secondary outcome was the rate of HPR. Standard dose of clopidogrel (75 mg daily) was used as a reference treatment.

A total of 12 RCTs testing 6 alternative strategies (i.e. clopidogrel 150 mg, prasugrel 3.75 mg, 5 mg, and 10 mg, ticagrelor 90 mg bid, and adjunctive cilostazol 100 mg bid) were included in the network. Compared with standard-dose clopidogrel, the greatest reduction in PRU was observed with prasugrel 10 mg (MD -127.91; 95% CI -141.04; -114.78) and ticagrelor 90 mg bid (MD -124.91; 95% CI -161.78; -88.04), followed by prasugrel 5 mg (MD -76.33; 95% CI -98.01; -54.65) and prasugrel 3.75 mg (MD -73.00; 95% CI -100.28; -45.72). Among other strategies, adjunctive cilostazol (MD -42.64; 95% CI -64.72; -20.57) and high-dose clopidogrel (MD -32.11; 95% CI -51.33; -12.90) were associated with a modest reduction in PRU compared with standard-dose clopidogrel.

Among carriers of CYP2C19 LoF alleles undergoing PCI, standard-dose prasugrel or ticagrelor are most effective in reducing platelet reactivity, while double-dose clopidogrel and additional cilostazol showed modest effects. Reduced-dose of prasugrel may represent a balanced strategy to overcome HPR without a significant increase in bleeding. The clinical implications of these pharmacodynamic findings warrant further investigation.

The CYP2C19 enzyme metabolizes clopidogrel, a prodrug, to its active form. Approximately 30% of individuals inherit a loss-of-function (LoF) polymorphism in the CYP2C19 gene, leading to reduced formation of the active clopidogrel metabolite. Reduced clopidogrel effectiveness has been well documented in patients with an LoF allele following an acute coronary syndrome or percutaneous coronary intervention. Prasugrel or ticagrelor is recommended in those with an LoF allele as neither is affected by CYP2C19 genotype. Although data demonstrate improved outcomes with a CYP2C19-guided approach to P2Y12 inhibitor selection, genotyping has not yet been widely adopted in clinical practice.

The development of percutaneous coronary intervention (PCI) has been one of the greatest advances in cardiology and has changed clinical practice for patients with coronary artery disease (CAD). Despite continuous improvements in operators' experience, techniques, and the development of new-generation devices, significant challenges remain in improving the efficacy of PCI, including calcification, bifurcation, multivascular disease, stent restenosis, and stent thrombosis, among others. The present review aims to provide an overview of the current status of knowledge of endovascular revascularization in CAD, including relevant trials, therapeutic strategies, and new technologies addressing particular scenarios that can impact the prognosis of this vulnerable population.

Cardiovascular diseases (CVDs) are the leading cause of mortality globally while also contributing to excess health system costs. Significant advancements have been made in the understanding and prevention of deaths from CVD. In addition to risk factor modifications, one of the key developments in this area is the appropriate prescribing of antiplatelet medications for secondary prevention of CVD. With the advent of vascular devices, there has been an increased use of potent antiplatelet agents to mitigate thrombosis risk. A well-recognized, albeit rare complication of antiplatelet drugs is the heightened risk of bleeding. This adverse effect is particularly relevant when a patient receiving these medications may require an urgent surgery. In addition, for elective surgeries, although these drugs can be withheld, there may be some situations when interruption of antiplatelet agents, even for short duration, may lead to thrombotic events. There are no robust guidelines on how to manage these clinical scenarios, although there have been some important studies published recently in this area. In this review, we provide our approach to patients on antiplatelet drugs who may require urgent surgeries or surgical interventions.

Patients with left ventricular assist devices (LVADs) are treated with a potent antithrombotic regimen to prevent pump thrombosis and thromboembolism. High on-treatment residual platelet reactivity (HRPR) is associated with ischemic outcomes in cardiovascular disease.

In the current study, we investigated the prevalence and clinical impact of HRPR in stable LVAD patients.

Pump thrombosis, bleeding events, and death were assessed in 62 LVAD patients (19 HeartWare HVAD [Medtronic] and 43 HeartMate 3 [Abbott]) during a 2-year follow-up. Platelet aggregation was measured by multiple electrode aggregometry, and HRPR was defined as arachidonic acid (AA)-inducible platelet aggregation of ≥21 aggregation units. Soluble P-selectin was determined by enzyme-linked immunosorbent assay.

Three patients (4.8%) had pump thrombosis and 10 patients (16.1%) suffered a bleeding complication. AA-inducible platelet aggregation was significantly higher in patients with pump thrombosis (P = .01), whereas platelet aggregation in response to adenosine diphosphate (ADP) and thrombin receptor-activating peptide (TRAP) was comparable between patients without and those with pump thrombosis (both P > .05). Platelet aggregation in response to AA, ADP, and TRAP was similar in patients without and with a bleeding event (all P > .05). HRPR was detected in 29 patients (46.8%) and was associated with significantly higher platelet aggregation in response to AA, ADP, and TRAP as well as higher levels of soluble P-selectin compared with patients without HRPR (all P < .05). All pump thromboses occurred in patients with HRPR (3 vs 0; P = .06) and HVAD.

Platelet reactivity is associated with pump thrombosis in LVAD patients. HRPR may represent a risk marker for pump thrombosis, particularly in HVAD patients.

Platelet-fibrin clot strength (PFCS) is linked to major adverse cardiovascular event (MACE) risk. However, the association between PFCS and platelet reactivity and their prognostic implication remains uncertain in patients undergoing percutaneous coronary intervention (PCI).

In PCI-treated patients (n = 2512) from registry data from January 2010 to November 2018 in South Korea, PFCS using thromboelastography and platelet reactivity using VerifyNow were measured. High PFCS (PFCSHigh) was defined as thromboelastography maximal amplitude ≥ 68 mm, and high platelet reactivity (HPR) was defined as >208 P2Y12 reaction units. Patients were stratified into four groups according to maximal amplitude and P2Y12 reaction unit levels: (i) normal platelet reactivity (NPR)-PFCSNormal (31.8%), (ii) HPR-PFCSNormal (29.0%), (iii) NPR-PFCSHigh (18.1%), and (iv) HPR-PFCSHigh (21.1%). Major adverse cardiovascular event (all-cause death, myocardial infarction, or stroke) and major bleeding were followed up to 4 years.

High platelet reactivity and PFCSHigh showed an additive effect for clinical outcomes (log-rank test, P < .001). Individuals with NPR-PFCSNormal, NPR-PFCSHigh, HPR-PFCSNormal, and HPR-PFCSHigh demonstrated MACE incidences of 7.5%, 12.6%, 13.4%, and 19.3%, respectively. The HPR-PFCSHigh group showed significantly higher risks of MACE compared with the NPR-PFCSNormal group [adjusted hazard ratio (HRadj) 1.89; 95% confidence interval (CI) 1.23-2.91; P = .004] and the HPR-PFCSNormal group (HRadj 1.60; 95% CI 1.12-2.27; P = .009). Similar results were observed for all-cause death. Compared with HPR-PFCSNormal phenotype, NPR-PFCSNormal phenotype was associated with a higher risk of major bleeding (HRadj 3.12; 95% CI 1.30-7.69; P = .010).

In PCI patients, PFCS and platelet reactivity demonstrated important relationships in predicting clinical prognosis. Their combined assessment may enhance post-PCI risk stratification for personalized antithrombotic therapy.

This research aims to investigate the impact of individualized antiplatelet therapy guided by thromboelastography with platelet mapping (TEG-PM) on the clinical outcomes of patients with non-cardiogenic ischemic stroke.

Among a total of 1264 patients, 684 individuals diagnosed with non-cardiogenic ischemic stroke underwent TEG-PM testing. Based on the adjustment of antiplatelet medication, these patients were divided into individual and control groups. Within the individual group, in accordance with the TEG-PM test results, a Maximum amplitude (MA) value greater than 47mm was defined as high residual platelet reactivity (HRPR), while an MA value less than 31mm was defined as low residual platelet reactivity (LRPR). Patients with arachidonic acid (AA) less than 50% and adenosine diphosphate (ADP) less than 30% were classified as aspirin-resistant or clopidogrel-resistant. Treatment strategies for antiplatelet medication were subsequently adjusted accordingly, encompassing increment, decrement, or replacement of drugs. Meanwhile, the control group maintained their original medication regimen without alterations.

The individual group included 487 patients, while the control group had 197. In the individual group, approximately 175 patients (35.9%) were treated with increased medication dosages, 89 patients (18.3%) with reduced dosages, and 223 patients (45.8%) switched medications. The results showed that the incidence rate of ischemic events in the individual group was lower than that of the control group (5.54% vs. 12.6%, P = 0.001), but no significant difference was observed in bleeding events. Cox regression analysis revealed age (hazard ratio, 1.043; 95% CI, 1.01-1.078; P = 0.011) and coronary heart disease (hazard ratio, 1.902; 95% CI, 1.147-3.153; P = 0.013) as significant risk factors for adverse events.

Individualized antiplatelet therapy based on TEG-PM results can reduce the risk of ischemic events in patients with non-cardiogenic ischemic stroke without increasing the risk of bleeding events or mortality. Advanced age and coronary heart disease were identified as risk factors affecting the outcomes of individualized antiplatelet therapy.

Clopidogrel is the most widely used P2Y12 receptor inhibitor (P2Y12i) as a part of dual antiplatelet therapy along with aspirin. Clopidogrel is a pro-drug and is metabolized to its active metabolite by the hepatic enzyme cytochrome P4502C19 (CYP2C19). This active metabolite is responsible for the antiplatelet action of clopidogrel. Recent studies have demonstrated that single nucleotide polymorphisms in the CYP2C19 gene, including CYP2C19*2,*3,*4, and *5 alleles, result in reduced production of the active metabolite of clopidogrel, and hence reduced inhibition of platelet aggregation. This in turn enhances the incidence of stent thrombosis and recurrent cardiovascular (CV) events. We report a case of coronary stent thrombosis due to clopidogrel resistance proven by CYP2C19 genotyping. We then review the literature on clopidogrel resistance and its impact on CV outcomes. Subsequently, we discuss the methods of diagnosis of resistance, evidence from clinical trials for tailoring clopidogrel therapy, the role of potent P2Y12 inhibitors, the current guidelines, and future directions.

This study evaluated the association of atherogenic index of plasma (AIP) with platelet reactivity and clinical outcomes according to acute myocardial infarction (AMI). The composite of 3-year adverse outcomes of all-cause death, myocardial infarction, and cerebrovascular accident was evaluated in 10,735 patients after successful percutaneous coronary intervention with drug-eluting stents. AIP was defined as the base 10 logarithm of the ratio of triglyceride to high-density lipoprotein cholesterol concentration. High platelet reactivity (HPR) was defined as ≥ 252 P2Y12 reactivity unit. An increase of AIP (per-0.1 unit) was related to the decreased risk of HPR [odds ratio (OR) 0.97, 95% confidence interval (CI) 0.96-0.99; P = 0.001] in non-AMI patients, not in AMI patients (OR 0.98, 95% CI 0.96-1.01; P = 0.138). The HPR was associated with the increased risk of composite outcomes in both non-AMI and AMI patients (all-P < 0.05). AIP levels were not independently associated with the risk of composite outcomes in both patients with non-AMI and AMI. In conclusion, an inverse association between AIP and the risk of HPR was observed in patients with non-AMI. This suggests that the association between plasma atherogenicity and platelet reactivity may play a substantial role in the development of AMI.Trial registration: NCT04734028.

Although age and body mass index (BMI) significantly affect platelet reactivity units and clinical outcomes after percutaneous coronary intervention, there are limited data on the relationship between high on-treatment platelet reactivity (HPR) and clinical outcomes on age and BMI differences. Thus, we investigated the association of HPR with clinical outcomes according to age and BMI.

The study analyzed 11 714 patients who underwent platelet function tests after percutaneous coronary intervention. The primary end point was the occurrence of major adverse cardiac and cerebrovascular events (MACCEs), whereas the secondary end point was major bleeding. HPR was defined as platelet reactivity units ≥252. Patients were categorized by age (<67 years of age or ≥67 years of age) and BMI (≤22.6 kg/m2 or >22.6 kg/m2). Patients <67 years of age with HPR had increases in both MACCEs (adjusted hazard ratio [HR], 1.436 [95% CI, 1.106-1.867]; P=0.007) and major bleeding (adjusted HR, 1.584 [95% CI, 1.095-2.290]; P=0.015) compared with the those with non-HPR, respectively. In patients ≥67 years of age with HPR, there were no differences in MACCEs, but there was a decrease in major bleeding (adjusted HR, 0.721 [95% CI, 0.542-0.959]; P=0.024). Meanwhile, patients with HPR with BMI >22.6 kg/m2 had increases in MACCEs (adjusted HR, 1.387 [95% CI, 1.140-1.688]; P=0.001). No differences were shown in major bleeding.

HPR was linked to an increase in MACCEs or a decrease in major bleeding in patients after percutaneous coronary intervention, depending on age and BMI. This study is the first to observe that clinical outcomes in patients with HPR after percutaneous coronary intervention may vary based on age and BMI. Because the study is observational, the results should be viewed as hypothesis generating and emphasize the need for randomized clinical trials.

Cangrelor may be used as a bridge when temporary interruption of dual antiplatelet therapy is necessary. However, the optimal dose and monitoring of cangrelor in patients remains unknown, especially in the setting of mechanical circulatory support (MCS). We conducted an observational, single-center, retrospective cohort study of patients who had percutaneous coronary intervention within 3 months and received cangrelor while admitted to any intensive care unit. The primary outcome was the incidence of any major adverse cardiovascular event. Secondary outcomes included VerifyNow platelet reactivity units (PRUs) measured while on cangrelor and any bleeding events while on cangrelor. A total of 92 patients were included. The most common reason for cangrelor use was in the periprocedural setting, with or without MCS (42%-45%), followed by NPO status (26%-28%) and MCS alone (22%-24%). The primary outcome of major adverse cardiovascular event occurred in 1 patient (1.1%). Of 92 patients, 77% had a P2Y12 level collected within 24 hours, and 89% of the cohort was able to achieve the goal P2Y12 PRU of <194. The median P2Y12 value within 24 hours of cangrelor initation was 115 PRU (40-168 PRU). We observed a bleed event rate of 23% (21/92). We found a standardized protocol of cangrelor dosing in critically ill patients who received a drug-eluting stent in the past 3 months to be successful in achieving a goal P2Y12 PRU. Although the optimal PRU remains unknown, cardiovascular clinicians may monitor these levels to help guide decisions regarding cangrelor management. Future randomized controlled trials should evaluate the optimal PRU threshold to balance risks of ischemia and bleeding.

Background: Antithrombotic therapy is crucial for secondary prevention of cardiovascular disease (CVD), but women with CVD may face increased bleeding complications post-percutaneous coronary intervention (PCI) under antithrombotic therapy. However, women are often underrepresented in clinical trials in this field, so evidence for sex-specific recommendations is lacking. Methods and Results: A search on PubMed was conducted for English-language articles addressing bleeding complications and antithrombotic therapy in women. Despite women potentially showing higher baseline platelet responsiveness than men, the clinical implications remain unclear. Concerning antiplatelet therapy post-PCI, although women have an elevated bleeding risk in the acute phase, no sex differences were observed in the chronic phase. However, women require specific considerations for factors such as age, renal function, and weight when determining the dose and duration of antiplatelet therapy. Regarding anticoagulation post-PCI, direct oral anticoagulants may pose a lower bleeding risk in women compared with warfarin. Concerning triple antithrombotic therapy (TAT) post-PCI for patients with atrial fibrillation, there is a lack of evidence on whether sex differences should be considered in the duration and regimen of TAT. Conclusions: Recent findings on sex differences in post-PCI bleeding complications did not provide enough evidence to recommend specific therapies for women. Further studies are needed to address this gap and recommend optimal antithrombotic therapy post-PCI for women.

High on-clopidogrel platelet reactivity (HPR) associates with ischemic risk in patients after percutaneous intervention (PCI). This study aimed to evaluate the association of HPR as assessed by multiple electrode aggregometry (MEA) with ischemic, thromboembolic, and bleeding risk in patients with atrial fibrillation (AF) undergoing PCI. Patients with AF and an indication for oral anticoagulation (OAC) were included in this prospective cohort study on day 1-3 after PCI. Platelet aggregation [U] was analyzed by MEA. HPR and low platelet reactivity (LPR) were defined as ADP-induced aggregation ≥ 46 U and ≤ 18 U, respectively. TRAP-6-induced aggregation reference was 94-156 U. The primary outcome was time to all-cause death, myocardial infarction, or stroke at 6 months. The secondary outcome was time to non-major clinically relevant bleedings or major bleedings. 159 patients were enrolled between May 2020 and May 2021. The median age was 78 years (interquartile range 72-82) and 111 (70%) were male. Median ADP- and TRAP-induced aggregation were 12 (6-17) and 49 (35-68) U, respectively. 147 (93%) patients had a low overall aggregability. HPR was detected in 2 patients (1%) and 125 (79%) had LPR. ADP-induced aggregation did not significantly associate with the primary outcome (r = 0.081, p = 0.309) but correlated inversely with bleeding risk (r = - 0.201, p = 0.011). HPR status as assessed by MEA among patients with AF after PCI was rare and overall aggregability was low. Conventional cut-off values for HPR might be inappropriate for these patients. ADP-induced aggregation might be helpful to identify patients at risk for bleeding.

Prasugrel is not approved for patients treated with flow diverters, which have a high metal coverage ratio. However, robust antiplatelet therapy with prasugrel may prevent thromboembolic complications. We administered prasugrel and aspirin to all patients treated with flow diverters and reported the safety of the antiplatelet therapy regimen.

This retrospective, single-center study evaluated the angiographic and clinical data of consecutive patients treated with flow diverters for cerebral unruptured aneurysms between June 2020 and May 2022. All patients received dual antiplatelet therapy, including prasugrel and aspirin. The administration of prasugrel ended 3 or 6 months after the procedure, whereas aspirin use continued for at least 12 months. Periprocedural complications (< 30 days post-procedure) and delayed complications (> 30 days post-procedure) were recorded.

During the study period, 120 unruptured aneurysms were treated with flow diverters in 110 patients. All patients, except one, survived longer than 12 months after the procedure. The rate of thromboembolic complications was 6.4%, and more than half of the patients had transient symptoms; one (0.9%) had a major ischemic stroke. One patient (0.9%) each had an asymptomatic, small subarachnoid hemorrhage and significant hemorrhagic complications with melena. The rate of permanent neurological deficits was 1.8%, and the mortality rate was 0.9%.

Dual antiplatelet therapy comprising routine use of prasugrel and aspirin for flow diverter-implanted patients possibly contributed to a low rate of thromboembolic complications and low risk of hemorrhagic complications.

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.

Various genetic and nongenetic variables influence the high on-treatment platelet reactivity (HTPR) in patients taking clopidogrel.

This study aimed to develop a novel machine learning (ML) model to predict HTPR in Chinese patients after percutaneous coronary intervention (PCI).

This cohort study collected information on 507 patients taking clopidogrel. Data were randomly divided into a training set (90%) and a testing set (10%). Nine candidate Machine learning (ML) models and multiple logistic regression (LR) analysis were developed on the training set. Their performance was assessed according to the area under the receiver operating characteristic curve, precision, recall, F1 score, and accuracy on the test set. Model interpretations were generated using importance scores by transforming model variables into scaled features and representing in radar plots. Finally, we established a prediction platform for the prediction of HTPR.

A total of 461 patients (HTPR rate: 19.52%) were enrolled in building the prediction model for HTPR. The XGBoost model had an optimized performance, with an AUC of 0.82, a precision of 0.80, a recall of 0.44, an F1 score of 0.57, and an accuracy of 0.87, which was superior to those of LR. Furthermore, the XGBoost method identified 7 main predictive variables. To facilitate the application of the model, we established an XGBoost prediction platform consisting of 7 variables and all variables for the HTPR prediction.

A ML-based approach, such as XGBoost, showed optimum performance and might help predict HTPR on clopidogrel after PCI and guide clinical decision-making. Further validated studies will strengthen this finding.

Coronary artery disease patients undergoing percutaneous coronary intervention (PCI) often exhibit reduced left ventricular ejection fraction (LVEF). However, the impact of LV dysfunction status in conjunction with platelet reactivity on clinical outcomes has not been previously investigated.

From the multicenter PTRG-DES (Platelet function and genoType-Related long-term prognosis in DES-treated patients) consortium, the patients were classified as preserved-EF (PEF: LVEF ≥ 50%) and reduced-EF (REF: LVEF< 5 0%) group by echocardiography. Platelet reactivity was measured using VerifyNow P2Y12 assay and high platelet reactivity (HPR) was defined as PRU ≥ 252. The major adverse cardiac and cerebrovascular events (MACCEs) were a composite of death, myocardial infarction, stent thrombosis and stroke at 5 years after PCI. Major bleeding was defined as Bleeding Academic Research Consortium bleeding types 3-5.

A total of 13,160 patients from PTRG-DES, 9,319 (79.6%) patients with the results of both PRU and LVEF were analyzed. The incidence of MACCE and major bleeding was higher in REF group as compared with PEF group (MACCEs: hazard ratio [HR] 2.17, P < 0.001, 95% confidence interval [CI] 1.85-2.55; major bleeding: HR 1.78, P < 0.001, 95% CI 1.39-2.78). The highest rate of MACCEs was found in patients with REF and HPR, and the difference between the groups was statistically significant (HR 3.14 in REF(+)/HPR(+) vs. PEF(+)/HPR(-) group, P < 0.01, 95% CI 2.51-3.91). The frequency of major bleeding was not associated with the HPR in either group.

LV dysfunction was associated with an increased incidence of MACCEs and major bleeding in patients who underwent PCI. The HPR status further exhibited significant increase of MACCEs in patients with LV dysfunction in a large, real-world registry.

ClinicalTrials.gov Identifier: NCT04734028.

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

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

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

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