Ticagrelor plus aspirin versus clopidogrel plus aspirin for platelet reactivity in patients with minor stroke or transient ischaemic attack: open label, blinded endpoint, randomised controlled phase II trial

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke: current evidence and future perspectives

Ischemic stroke is a leading cause of death and disability worldwide, with an increasing trend and tendency for onset at a younger age. China, in particular, bears a high burden of stroke cases. In recent years, the inflammatory response after stroke has become a research hotspot: understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its treatment. This review summarizes several major cells involved in the inflammatory response following ischemic stroke, including microglia, neutrophils, monocytes, lymphocytes, and astrocytes. Additionally, we have also highlighted the recent progress in various treatments for ischemic stroke, particularly in the field of stem cell therapy. Overall, understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient outcomes. Stem cell therapy may potentially become an important component of ischemic stroke treatment.

Model based on single-nucleotide polymorphism to discriminate aspirin resistance patients

BACKGROUND

Aspirin is widely used for preventing ischaemic events. About 20%-40% of patients have aspirin resistance (ASR), which prevents them from benefiting from aspirin medication. This study aimed to develop and validate a model based on single-nucleotide polymorphism (SNP) to distinguish ASR patients.

METHODS

We included patients with spontaneous intracerebral haemorrhage and continuing antiplatelet therapy from a multicentre, prospective cohort study as the derivation cohort. Thromboelastography (inhibition of arachidonic acid channel<50%) was used to identify ASR. Genotyping was performed to identify the ASR-related SNP. Based on the result of the logistic analysis, the aspirin resistance in the Chinese population score (ASR-CN score) was established, and its accuracy was evaluated using the area under the curve (AUC). Patients receiving dual antiplatelet therapy for unruptured intracranial aneurysm embolism were prospectively included in the validation cohort. After embolism, 30-day ischaemic events, including ischaemic stroke, new or more frequent transient ischaemic attack, stent thrombosis and cerebrovascular death, were recorded.

RESULTS

The derivation cohort included 212 patients (155 male patients and the median age as 59). 87 (41.0%) individuals were identified with ASR. The multivariate logistic analysis demonstrated six SNPs of GP1BA, TBXA2R, PTGS2 and NOS3 as risk factors related to ASR. The ASR-CN score integrating these SNPs performed well to discriminate ASR patients from non-ASR patients (AUC as 0.77). Based on the validation cohort of 372 patients receiving antiplatelet therapy after embolism (including 130 ASR patients), the ASR-CN score continued to distinguish ASR patients with good accuracy (AUC as 0.80). Patients with high a ASR-CN score were more likely to suffer from 30-day ischaemic events after embolism (OR, 1.28; 95% CI, 1.10 to 1.50; p=0.002).

CONCLUSION

GP1BA, TBXA2R, PTGS2 and NOS3 were SNPs related to ASR. The ASR-CN score is an effective tool to discriminate ASR patients, which may guide antiplatelet therapy.

CLINICAL TRIAL REGISTRATION

Surgical Treatments of Antiplatelet Intracerebral Hemorrhage cohort (unique identifier: ChiCTR1900024406, http://www.chictr.org.cn/edit.aspx?pid=40640&htm=4).

Ticagrelor versus clopidogrel in dual antiplatelet therapy after minor stroke or transient ischemic attack: an updated network meta-analysis

BACKGROUND

Dual antiplatelet therapy (DAPT) with clopidogrel plus aspirin is a well-established practice after a minor stroke or transient ischemic attack (TIA). However, ticagrelor plus aspirin may be an alternative.

AIMS

We systematically searched PubMed, Embase, and Cochrane Central from inception to January 2024. We included randomized controlled trials (RCTs) enrolling adults with acute minor stroke or TIA within 72 hours of the onset of the symptoms.

RESULTS

A total of 8 RCTs were included in our meta-analysis. Ticagrelor plus aspirin (RR, 0.70; 95% CrI 0.52, 0.91) and clopidogrel plus aspirin (RR, 0.79; 95% CrI 0.64, 0.98) were superior to aspirin in preventing stroke recurrence in overall analysis. Excluding studies with dual antiplatelet up to 90 days, ticagrelor plus aspirin was the only strategy that maintained superiority compared with aspirin regarding stroke recurrence (RR, 0.70; 95% CrI 0.51, 0.95) and ischemic stroke (RR, 0.68; 95% CrI 0.47, 0.94). There was no significant difference between treatment groups regarding hemorrhagic stroke, functional disability, and mortality.

CONCLUSIONS

DAPTs were superior to aspirin in preventing recurrence or ischemic stroke. Although no significant difference was observed between DAPTs, ticagrelor plus aspirin may be related to worse major bleeding results, including intracranial bleeding. Ticagrelor plus aspirin is a considerable option for patients after a minor stroke or TIA.

Ninety-Day Stroke Recurrence in Minor Stroke: Systematic Review and Meta-Analysis of Trials and Observational Studies

BACKGROUND

Risk of recurrence after minor ischemic stroke is usually reported with transient ischemic attack. No previous meta-analysis has focused on minor ischemic stroke alone. The objective was to evaluate the pooled proportion of 90-day stroke recurrence for minor ischemic stroke, defined as a National Institutes of Health Stroke Scale severity score of ≤5.

METHODS AND RESULTS

Published papers found on PubMed from 2000 to January 12, 2021, reference lists of relevant articles, and experts in the field were involved in identifying relevant studies. Randomized controlled trials and observational studies describing minor stroke cohort with reported 90-day stroke recurrence were selected by 2 independent reviewers. Altogether 14 of 432 (3.2%) studies met inclusion criteria. Multilevel random-effects meta-analysis was performed. A total of 6 randomized controlled trials and 8 observational studies totaling 45 462 patients were included. The pooled 90-day stroke recurrence was 8.6% (95% CI, 6.5-10.7), reducing by 0.60% (95% CI, 0.09-1.1; P=0.02) with each subsequent year of publication. Recurrence was lowest in dual antiplatelet trial arms (6.3%, 95% CI, 4.5-8.0) when compared with non-dual antiplatelet trial arms (7.2%, 95% CI, 4.7-9.6) and observational studies 10.6% (95% CI, 7.0-14.2). Age, hypertension, diabetes, ischemic heart disease, or known atrial fibrillation had no significant association with outcome. Defining minor stroke with a lower National Institutes of Health Stroke Scale threshold made no difference - score ≤3: 8.6% (95% CI, 6.0-11.1), score ≤4: 8.4% (95% CI, 6.1-10.6), as did excluding studies with n<500%-7.3% (95% CI, 5.5-9.0).

CONCLUSIONS

The risk of recurrence after minor ischemic stroke is declining over time but remains important.

Comparison of Dual Antiplatelet Therapies for Minor, Nondisabling, Acute Ischemic Stroke: A Bayesian Network Meta-Analysis

Importance

Dual antiplatelet therapy (DAPT) appears to be an effective treatment option for minor (nondisabling) acute ischemic stroke. This conclusion is based on trials that include both transient ischemic attack (TIA) and minor stroke; however, these 2 conditions may differ.

Objective

To compare DAPT regimens specifically for minor stroke.

Data Sources

PubMed was searched for randomized clinical trials published up to November 4, 2023. Search terms strategy included TIA, transient ischemic attack, minor stroke, or moderate stroke, with the filter randomized controlled trial. Unpublished data on minor stroke were sourced from authors and/or institutions.

Study Selection

Trials testing DAPT within the first 24 hours of a minor stroke (defined as a National Institutes of Health Stroke Scale score ≤5) were included by consensus. Of 1508 studies screened, 6 (0.3%) initially met inclusion criteria and were reviewed.

Data Extraction and Synthesis

The study was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines by multiple observers. Bayesian fixed-effect network meta-analysis was conducted. Secondary analysis performed for high-risk TIA alone.

Main Outcomes and Measures

Treatments were ranked using a probability measure called surface under the cumulative rank curve (SUCRA). The primary outcome was subsequent ischemic stroke at 90 days. Secondary outcomes included major hemorrhage, mortality, and hemorrhagic stroke. The number needed to treat (NNT) and number needed to harm (NNH) were obtained.

Results

Five trials were included that described 28 148 patients, of whom 22 203 (78.9%) had a minor stroke. Of these, 13 995 (63.0%) were in DAPT groups and 8208 (37.0%) in aspirin (acetylsalicylic acid) groups. Aspirin and ticagrelor had a 94% probability of being the superior treatment for minor stroke (SUCRA, 0.94) for the primary outcome. Both aspirin and ticagrelor (NNT, 40; 95% CI, 31-64) and aspirin and clopidogrel (NNT, 58; 95% CI, 39-136) were superior to aspirin alone in the prevention of recurrent ischemic stroke at 90 days. Both treatments had higher rates of major hemorrhage than aspirin alone (NNH for aspirin and ticagrelor, 284; 95% CI, 108-1715 vs NNH for aspirin and clopidogrel, 330; 95% CI, 118-3430), but neither had increased risk of hemorrhagic stroke or death. For high-risk TIA, ticagrelor and aspirin had a 60% probability (SUCRA, 0.60) and clopidogrel and aspirin had a 40% probability (SUCRA 0.40) of being a superior treatment; neither was optimum, but both were superior to aspirin alone for the primary outcome.

Conclusions and Relevance

These findings suggest that DAPT with aspirin and ticagrelor has higher probability of being the superior treatment among patients with minor stroke when presence of CYP2C19 loss-of-function alleles has not been excluded. For patients with TIA, the superiority of aspirin and ticagrelor vs aspirin and clopidogrel was not demonstrated.

The association of CYP2C19 LoF alleles with adverse clinical outcomes in stroke patients taking clopidogrel: An updated meta-analysis

The aggregated risk of recurrent stroke in stroke/transient ischemic attack (TIA) patients carrying CYP2C19 LoF alleles who take clopidogrel has not been investigated recently, and the available research is limited. This study aimed to perform an updated meta-analysis to assess the association between CYP2C19 LoF alleles and the risk of recurrent stroke in patients taking clopidogrel. Databases were searched for the literature on eligible studies. The end points were recurrent stroke, composite vascular events, and bleeding events. Odds ratios (ORs) were calculated using RevMan software, where p < 0.05 was considered statistically significant. Patients carrying CYP2C19 LoF alleles who were treated with clopidogrel had a significantly increased risk of recurrent ischemic stroke compared with non-carriers (OR 2.18, 96% CI 1.80-2.63; p < 0.00001). The risk of recurrent stroke was only significantly different in Asian patients (OR 2.29, 96% CI 1.88-2.80; p < 0.00001) but not in patients of other ethnicities; however, there were a limited number of studies in other ethnic groups. Both observational studies (OR 2.83, 96% CI 2.20-3.65; p < 0.00001) and RCTs (OR 1.48, 96% CI 1.10-1.98; p = 0.009) found associations with a significantly increased risk of recurrent ischemic stroke. Asian stroke patients or TIA patients carrying CYP2C19 LoF alleles and taking clopidogrel were at a significantly higher risk of recurrent ischemic stroke than non-carriers. Significantly increased risk of recurrent ischemic stroke was found in both observational studies and RCTs.

Non-adaptive cognitive emotion regulation mediates the relationship between disease uncertainty and acute stress disorder in patients with ischaemic stroke

Background

During epidemic outbreaks, hospitalized patients, especially those with cerebrovascular disease, were identified as a vulnerable group suffering from acute stress disorder (ASD) and consequent psychological distress. For stroke patients, not only will they suffer from physical illness, but the uncertainty of illness caused by sudden illness may also cause patients to experience different degrees of ASD. Relevant studies have shown that the impact of ASD on individuals may vary according to age, gender, disease characteristics, individual personality, treatment methods, income level, family support, cognitive psychology and other factors. However, non-adaptive cognitive emotion regulation plays a crucial role in influencing individual psychological states. At present, the risk factors of ASD after stroke and the mechanism between illness uncertainty and cognitive emotion regulation are not fully understood. Therefore, we focus on exploring the predictive effects of general demographic and disease-related characteristics, maladaptive cognitive emotion regulation, and illness uncertainty on ASD after stroke, and make hypotheses. When a disease acts on the body, the patient will have the corresponding cognition of the disease, and ASD will appear at the same time. Then the maladaptive cognitive emotion regulation as an important mediating variable can aggravate the level of acute stress disorder and be verified.

Methods

We used a cross-sectional design, which can be used to investigate the distribution of a disease or health condition and its related factors in a specific population at a specific time, so as to describe the distribution of the disease or health condition and its relationship with related factors. A total of 256 hospitalized patients with ischemic stroke were enrolled, including 145 males and 111 females, aged from 26 to 90 years, with a mean age of (64.71 ± 12.20) years. All patients completed and returned a self-report questionnaire that included demographic information, illness uncertainty, cognitive emotion regulation, and ASD. We then compared the differences in general demographic data, illness uncertainty, and maladaptive cognitive emotion regulation in acute stress disorders.

Results

The majority of hospitalized stroke patients (67.6%) developed ASD due to the COVID-19 pandemic and were therefore at risk for PTSD. More than one third (39.1%) of stroke survivors also suffered from severe psychological distress. More specifically, younger stroke patients are more likely to experience ASD than older patients. Although higher illness uncertainty scores indicate more severe ASD, adaptive cognitive emotion regulation was a protective factor.

Conclusion

Given that individuals with ASD are susceptible to PTSD, it is critical to follow up hospitalized patients with ischemic stroke for screening for PTSD and referral to appropriate psychological services. Maladaptive cognitive emotion regulation can increase the impact of uncertainty on the traumatic experience of stroke patients. Therefore, health care institutions should increase their efforts to provide psychosocial support services to hospitalized patients and make continuous efforts to screen for symptoms of trauma and psychological distress in hospitalized stroke patients.

LDL-C Levels and Bleeding Risk in Patients Taking DAPT After Minor Ischemic Stroke or TIA

Importance

Evidence on the bleeding risk associated with low-density lipoprotein cholesterol (LDL-C) levels in patients receiving dual antiplatelet therapy (DAPT) remains sparse.

Objective

To investigate the association of LDL-C levels with bleeding risk in patients with minor ischemic stroke (MIS) or high-risk transient ischemic attack (HRTIA) receiving DAPT.

Design, Setting, and Participants

This cohort study was an analysis of pooled data from 2 randomized, double-blind, placebo-controlled clinical trials in China of patients with MIS or HRTIA who were receiving DAPT: the CHANCE (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) trial enrolled patients at 114 sites from October 2009 to July 2012, and the CHANCE-2 enrolled patients at 202 centers from September 2019 to March 2021. Both sets of patients were followed up for 90 days. Data analysis was performed from August 2022 to May 2023.

Exposures

Baseline LDL-C levels and receipt of ticagrelor-aspirin and clopidogrel-aspirin DAPT.

Main Outcomes and Measures

The primary outcome was any bleeding, and the secondary outcome was severe or moderate bleeding within 3 months after randomization. The association of LDL-C levels and all outcomes was assessed by using the Cox proportional hazard model. Hazard ratios (HRs) with 95% CIs were calculated on univariable (unadjusted) Cox regression models. Adjusted HRs (aHRs) and their 95% CIs were calculated on multivariable Cox regression models.

Results

In total, 8996 patients with acute MIS or HRTIA who were receiving DAPT were included in the 2 trials, of whom 1066 without serum specimens and 490 patients with missing baseline LDL-C value were excluded. Finally, 7440 patients with DAPT (4486 in the clopidogrel-aspirin group and 2954 in the ticagrelor-aspirin group) were included in this study. The median (IQR) age was 64.32 (56.56-71.30) years, and 2479 patients (33.32%) were women. A total of 270 (3.63%) bleeding events were reported at 3 months, and LDL-C less than 70 mg/dL was associated with an increased risk of both any bleeding (aHR, 1.48; 95% CI, 1.03-2.12), and severe or moderate bleeding (aHR, 2.78; 95% CI, 1.18-6.53). The risk of any bleeding was increased at lower LDL-C levels in the ticagrelor-aspirin group (aHR, 1.71; 95% CI, 1.08-2.72). However, an increased risk of any bleeding was not observed in the clopidogrel-aspirin group (aHR, 1.30; 95% CI, 0.73-2.30). There was no significant association between LDL-C levels and the risk of severe or moderate bleeding in either the ticagrelor-aspirin or clopidogrel-aspirin group.

Conclusions and Relevance

These findings suggest that low LDL-C levels are associated with an increased bleeding risk within 3 months among patients with MIS or HRTIA receiving DAPT, especially those taking ticagrelor-aspirin. Weighing the risks and benefits is crucial when simultaneously considering the selection of LDL-C target strategies and DAPT regimens among these patients.

Differential effect of ticagrelor versus clopidogrel by homocysteine levels on risk of recurrent stroke: a post hoc analysis of the CHANCE-2 trial

BACKGROUND

Elevated homocysteine levels are associated with increased blood coagulation and platelet activity and may modulate the response to antiplatelet therapies. We aimed to investigate the effects of homocysteine levels on the efficacy and safety of ticagrelor-acetylsalicylic acid (ASA) versus clopidogrel-ASA among patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles.

METHODS

We conducted a post hoc analysis of the CHANCE-2 (The Clopidogrel in High-risk Patients with Acute Nondisabling Cerebrovascular Events-II) trial. Participants were randomly assigned to treatment with ticagrelor-ASA or clopidogrel-ASA. We categorized participants into groups with elevated and non-elevated homocysteine levels, based on the median level. The primary efficacy outcome was recurrent stroke within 90-day follow-up. The primary safety outcome was severe or moderate bleeding within 90 days.

RESULTS

A total of 2740 participants were randomly assigned to receive ticagrelor-ASA and 2700 to receive clopidogrel-ASA. Use of ticagrelor-ASA was associated with a reduced risk of recurrent stroke among participants with elevated homocysteine levels (74 [5.3%] v. 119 [8.5%]; hazard ratio [HR] 0.60, 95% confidence interval [CI] 0.45-0.81), but not among those with non-elevated levels (86 [6.4%] v. 87 [6.7%]; HR 0.97, 95% CI 0.71-1.32; p = 0.04 for interaction). When analyzed as a continuous variable, the benefits of ticagrelor-ASA with regard to recurrent stroke increased as homocysteine levels increased (p = 0.04 for interaction). No significant interaction between homocysteine levels and treatment with regard to severe or moderate bleeding was observed (p = 0.7 for interaction). We found a significant interaction between homocysteine levels and therapy with regard to recurrent stroke in females (p = 0.04 for interaction) but not males.

INTERPRETATION

In comparison with clopidogrel-ASA, ticagrelor-ASA conferred more benefit to patients with elevated homocysteine levels, particularly to female patients, in this secondary analysis of a randomized controlled trial involving patients with minor ischemic stroke or TIA.

TRIAL REGISTRATION

ClinicalTrials.gov, no. NCT04078737.

METTL3-mediated methylation of CYP2C19 mRNA may aggravate clopidogrel resistance in ischemic stroke patients

Background

N6-methyladenosine (m6A) is the most frequently occurring interior modification in eukaryotic messenger RNA (mRNA), and abnormal mRNA modifications can affect many biological processes. However, m6A's effect on the metabolism of antiplatelet drugs for the prevention of ischemic stroke (IS) remains largely unclear.

Methods

We analyzed the m6A enzymes and m6A methylation in peripheral blood samples of IS patients with/without clopidogrel resistance (CR), and the peripheral blood and liver of rat models with/without CR. We also compared the effect of m6A methylation on the expression of the drug-metabolizing enzymes (CYP2C19 and CYP2C6v1) in CR and non-CR samples.

Results

Methyltransferase-like 3 (METTL3), an m6A enzyme, was highly expressed in the peripheral blood of patients with CR, and in both the peripheral blood and liver of rats with CR. This enzyme targets CYP2C19 or CYP2C6v1 mRNA through m6A methylation, resulting in low expression of CYP2C19 or CYP2C6v1 mRNA. Consequently, this leads to decreased clopidogrel metabolism and CR.

Conclusion

The METTL3-mediated methylation of CYP2C19 mRNA may aggravate CR in IS patients.

Optimal Medical Management of Atherosclerotic Intracranial Stenosis

Reducing the high risk of recurrent stroke in patients with symptomatic intracranial atherosclerotic stenosis (sICAS) has proven to be challenging, but aggressive medical management, with intensive risk factor control and antithrombotic therapy, has been shown to be beneficial. High-intensity statins are recommended for patients with atherosclerotic stroke, including sICAS. Ezetimibe and PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitors are beneficial for those who fail to reach low-density lipoprotein targets or those with statin intolerance. The treatment target for sICAS is low-density lipoprotein <70 mg/dL. In neurologically stable patients, blood pressure should be treated to goal <140/90 mm Hg with the use of thiazide diuretics, angiotensin-converting enzyme inhibitors, or angiotensin II receptor blockers preferentially. For those with diabetes, treat to goal hemoglobin A1C ≤7% for most patients through combination of diet, insulin, and hypoglycemic drugs. Some degree of physical activity (eg, walking, stationary biking with arms or legs, etc) should be encouraged in all patients with sICAS who are not severely disabled. A minimum of 10 minutes of moderate-intensity aerobic activity 4 times a week is recommended for patients who are capable of exercise. For all patients with severe sICAS (70%-99% stenosis), dual antiplatelet therapy for up to 90 days followed by single antiplatelet agent is recommended.

Dual Antiplatelet Therapy for the Acute Management and Long-term Secondary Prevention of Ischemic Stroke and Transient Ischemic Attack, An Updated Review

To improve the efficacy over antiplatelet monotherapy, dual antiplatelet therapy (DAPT) has been increasingly adopted in the management of non-cardioembolic stroke. For minor ischemic stroke and high-risk transient ischemic attack, the aspirin-clopidogrel combination is now recommended for acute short-term treatment, whereas aspirin-ticagrelor combination may be considered in selected patients, especially those with resistance to clopidogrel. For long-term stroke prevention, aspirin-dipyridamole combination has been used as an alternative to antiplatelet monotherapy, and aspirin or clopidogrel combined with cilostazole may be prescribed for added protection in high-risk patients. In this paper, we review the development of DAPT from a historical perspective and describe the findings from major clinical trials published up until the end of 2023. Using the 2021 American Heart Association guideline for secondary stroke prevention as a basis for our recommendations, we further discuss areas of controversy and more recent developments to provide an updated review for clinicians to consider in their daily practice.

Chinese Stroke Association guidelines for clinical management of ischaemic cerebrovascular diseases: executive summary and 2023 update

BACKGROUND

China is one of the countries with the highest burden of stroke. Implementing multidimensional management guidelines will help clinicians practise evidence-based care, improve patient outcomes and alleviate societal burdens. This update of the 2019 edition will provide the latest comprehensive recommendations for the diagnosis and treatment of ischaemic cerebrovascular diseases.

METHODS

We conducted a comprehensive search on MEDLINE (via PubMed) up to 31 August 2023. The writing team established the recommendations through multiple rounds of online and offline discussions. Each recommendation was graded using the evidence grading algorithm developed by the Chinese Stroke Association (CSA). The draft was reviewed and finalised by the CSA Stroke Guidelines Writing Committee.

RESULTS

This update included revisions of 15 existing recommendations and 136 new recommendations in the following areas of stroke care: emergency assessment and diagnosis of ischaemic cerebrovascular disease, acute-phase reperfusion therapy, evaluation of underlying mechanisms, antithrombotic therapy, prevention and treatment of complications, and risk factor management.

CONCLUSIONS

This guideline updated the recommendations for the clinical management of ischaemic cerebrovascular disease from 2019.

Ticagrelor Versus Clopidogrel in Minor Stroke or Transient Ischemic Attack With Intracranial Artery Stenosis: A Post Hoc Analysis of CHANCE-2

Background This study aimed to investigate the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in Chinese patients by the presence and clinical presentation of intracranial artery stenosis (ICAS) using randomized trial data from the CHANCE-2 (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events-II) trial. Methods and Results A total of 6412 patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles were randomized to either the ticagrelor-aspirin or clopidogrel-aspirin group. Patients without imaging of the intracranial artery were excluded from the nonprespecified subgroup analysis of CHANCE-2. All patients included were classified into the following groups: without ICAS, symptomatic ICAS, or asymptomatic ICAS. The primary efficacy outcome was new strokes within 90 days. There were 5893 patients (median age, 64.8 years; 33.9% women) included, and 172 (4.9%), 171 (10.5%), and 57 (7.7%) cases of new strokes occurred within 90 days in the without ICAS, with symptomatic ICAS, and with asymptomatic ICAS groups, respectively. Ticagrelor-aspirin was associated with reduced risk of new stroke in patients without ICAS (62 [3.5%] versus 110 [6.3%]; hazard ratio [HR], 0.57 [95% CI, 0.41-0.78]) but not in those with symptomatic ICAS (HR, 0.77 [95% CI, 0.56-1.05]) or in those with asymptomatic ICAS (HR, 0.77 [95% CI, 0.43-1.38]) compared with clopidogrel-aspirin (P for interaction=0.14). There were no significant differences in the proportion of severe or moderate bleeding events among different ICAS groups. Conclusions Patients without ICAS received a significantly greater benefit from ticagrelor-aspirin than clopidogrel-aspirin after minor ischemic stroke or transient ischemic attack, and there was no statistically significant difference between treatments in patients with symptomatic ICAS or asymptomatic ICAS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04078737.

The mediating role of anxiety in disease uncertainty and acute stress in acute ischaemic stroke patients in the post-epidemic era

Objective

To analyse the influencing factors of anxiety, disease uncertainty and acute stress response in patients with acute ischaemic stroke, and to verify the mediating role of anxiety in the post-epidemic era.

Methods

240 patients with acute ischaemic stroke were selected from a tertiary hospital in Wuhan City and investigated by questionnaire and convenience sampling methods.

Results

The total anxiety score, disease uncertainty and acute stress reaction were at moderate levels. Anxiety was positively correlated with illness uncertainty, and anxiety and acute stress response were negatively correlated. Multiple linear regression analysis showed that Sickness uncertainty, acute stress response, age, and work status influenced anxiety. Anxiety mediated the prediction of Sickness uncertainty and acute stress response, with the mediating effect accounting for 35.6% of the total effect.

Conclusion

Disease uncertainty in patients with acute ischaemic stroke in the post-epidemic era directly affects the acute stress response and indirectly through anxiety.

Antithrombotic Therapy for Primary and Secondary Prevention of Ischemic Stroke: JACC State-of-the-Art Review

Stroke is a devastating condition with significant morbidity and mortality worldwide. Antithrombotic therapy plays a crucial role in both primary and secondary prevention of stroke events. Single or dual antiplatelet therapy is generally preferred in cases of large-artery atherosclerosis and small-vessel disease, whereas anticoagulation is recommended in conditions of blood stasis or hypercoagulable states that mostly result in red thrombi. However, the benefit of antithrombotic therapies must be weighed against the increased risk of bleeding, which can pose significant challenges in the pharmacological management of this condition. This review provides a comprehensive summary of the currently available evidence on antithrombotic therapy for ischemic stroke and outlines an updated therapeutic algorithm to support physicians in tailoring the strategy to the individual patient and the underlying mechanism of stroke.

Using the PEAR1 Polymorphisms Rs12041331 and Rs2768759 as Potential Predictive Markers of 90-Day Bleeding Events in the Context of Minor Strokes and Transient Ischemic Attack

In this study, we explored the relationship between the platelet endothelial aggregation receptor 1 (PEAR1) polymorphisms, platelet reactivity, and clinical outcomes in patients with minor stroke or transient ischemic attack (TIA). Randomized controlled trial subgroups were assessed, wherein patients received dual antiplatelet therapy for at least 21 days. Platelet reactivity was measured at different time intervals. Genotypes were categorized as wild-type, mutant heterozygous, and mutant homozygous. Clinical outcomes were evaluated after 90 days. The rs12041331 polymorphism predominantly influenced adenosine diphosphate channel platelet activity, with the AA genotype displaying significantly lower residual platelet activity to the P2Y12 response unit (p < 0.01). This effect was more evident after 7 days of dual antiplatelet treatment (p = 0.016). Mutant A allele carriers had decreased rates of recurrent stroke and complex endpoint events but were more prone to bleeding (p = 0.015). The rs2768759 polymorphism majorly impacted arachidonic acid (AA) channel platelet activity, which was particularly noticeable in the C allele carriers. Our regression analysis demonstrated that rs12041331 AA + GA and rs2768759 CA predicted 90-day post-stroke bleeding. In conclusion, the PEAR1 polymorphisms rs12041331 and rs2768759 interfere with platelet aggregation and the performance of antiplatelet drugs. These genetic variations may contribute to bleeding events associated with minor stroke and TIA.

Dual Antiplatelet Therapies and Causes in Minor Stroke or Transient Ischemic Attack: A Prespecified Analysis in the CHANCE-2 Trial

BACKGROUND

It is unclear whether patients with different stroke/transient ischemic attack etiologies benefit differently from gene-directed dual antiplatelet therapy. This study explored the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in transient ischemic attack or minor stroke with different causes in the CHANCE-2 trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events-II).

METHODS

This was a prespecified analysis of the CHANCE-2 trial, which enrolled 6412 patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles. Patients with centralized evaluation of TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification of large-artery atherosclerosis, small-vessel occlusion, and stroke of undetermined cause were included. The primary efficacy outcome was new stroke, and the primary safety outcome was severe or moderate bleeding, both within 90 days. Cox proportional hazards models were used to assess the interaction of TOAST classification with the effects of dual antiplatelet therapy with ticagrelor-aspirin versus clopidogrel-aspirin.

RESULTS

A total of 6336 patients were included in this study. In patients administered ticagrelor-aspirin and clopidogrel-aspirin, respectively, stroke recurred in 85 (9.8%) and 88 (10.7%) patients with large-artery atherosclerosis (hazard ratio, 0.86 [95% CI, 0.63-1.18]; P=0.34); 32 (3.6%) and 61 (7.0%) patients with small-vessel occlusion (hazard ratio, 0.51 [95% CI, 0.33-0.79]; P=0.002); and 68 (4.8%) and 87 (5.9%) patients with stroke of undetermined cause (hazard ratio, 0.80 [95% CI, 0.58-1.10]; P=0.17), with P=0.08 for the treatment×cause subtype interaction effect. There were no significant differences in severe or moderate bleeding events in patients with different cause and different treatment.

CONCLUSIONS

In this prespecified analysis of the CHANCE-2 trial, the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in preventing new stroke were consistent in patients with different causes. The influence of stroke cause on benefit of gene-guided antiplatelet therapy should be explored by further trials.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04078737.

Clinical evidence in ischemic stroke: Where we have gone so far and hopes for the future

OBJECTIVE

Ischemic stroke is a significant cause of disability and death worldwide. Randomized clinical trials (RCTs) are important in changing guidelines and treatment strategies. This study aimed to analyze the progress of RCTs in ischemic stroke and to guide future research directions.

METHODS

Ischemic stroke-related RCT articles were identified in six high-impact medical journals using the Web of Science Core Collection database. Google Scholar was used to check whether relevant articles were included in the guidelines. The characteristics of these articles were analyzed and future research hotspots were predicted.

RESULTS

389 relevant articles were included in the analysis. The number of articles increased rapidly from 1972 to 2022, from 5 (1.3%; 1972-1982) to 208 (53.5%; 2013-2022) articles. 338 (86.9%) articles were included in relevant guidelines. According to corresponding author location, Europe was the source of the highest number of publications (183; 47.0%), followed by the Americas (152; 39.1%) and the Western Pacific (54; 13.9%). The number of publications steadily increased over time in the USA, England, Canada, Australia, Germany, and France, and surged in China and Spain, especially in the last 5 years. In recent years, endovascular therapy has accounted for the majority of ischemic stroke-related RCT articles.

CONCLUSIONS

Numerous RCTs related to ischemic stroke have been conducted in recent decades, and both the number of articles and their contribution to guideline updates are increasing. Also, a shift in research topics was observed. However, great regional imbalances in this research exist, calling for more research to be conducted in specific regions to promote the generalizability of trial conclusions.

Ticagrelor plus aspirin in patients with minor ischemic stroke and transient ischemic attack: a network meta-analysis

BACKGROUND

Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel was recommended as the secondary prevention of minor ischemic stroke or transient ischaemic attack (TIA). However, genetic polymorphisms of CYP2C19 had been identified as the major cause of poor responsiveness to clopidogrel. Ticagrelor, unlike clopidogrel, did not depend on metabolic activation, but it remained unclear whether ticagrelor was superior to clopidogrel in ischemic stroke. We performed a network meta-analysis to compare the efficacy and safety of ticagrelor, clopidogrel, and aspirin in the minor ischemic stroke and TIA populations.

METHODS

Databases of Cochrane Library, ClinicalTrials.gov, and PubMed were searched up to June 19, 2023. Randomized controlled trials (RCTs) assessing antiplatelet drugs for minor stroke or TIA were included. Statistical processing was conducted by using multivariate meta-analysis routines of STATA.

RESULTS

Seven RCTs were included involving 41,745 participants. There was no significant difference between the two DAPTs in preventing stroke recurrence (OR, 1.16; 95% CI, 0.93-1.44), ischemic stroke recurrence (OR, 1.16; 95% CI, 0.93-1.45), and major hemorrhage (OR, 1.22; 95% CI, 0.62,2.39). Compared with aspirin alone, the two DAPT regimen reduced the risk of stroke recurrence (clopidogrel: OR, 0.69; 95% CI, 0.60-0.80, ticagrelor: OR, 0.66; 95% CI, 0.49-0.87) and ischemic stroke recurrence, but increased the incidence of major hemorrhage (clopidogrel: OR, 2.05; 95% CI, 1.22- 3.77; ticagrelor: OR, 2.55; 95% CI, 1.25-4.99). Despite being associated with a higher risk of any bleeding, ticagrelor did not impact the composite of vascular events or mortality. While ticagrelor and aspirin reduced the risk of ischemic stroke recurrence (OR, 0.77; 95% CI, 0.63- 0.92) without increasing the risk of major bleeding (OR 0.94; 95% CI 0.45-1.95) in the Asian population mainly Chinese.

CONCLUSIONS

DAPT was superior to aspirin in stroke prevention, but little difference existed between the two DAPT regimens. Asian population mainly Chinese may benefit from DAPT with aspirin and ticagrelor. But further head-to-head RCTs are needed to validate the study results.

Ticagrelor versus clopidogrel after intracranial stent angioplasty: a real-world study

Objective

It was unknown whether a regimen of aspirin plus ticagrelor (aspirin-ticagrelor) attenuates ischemic vascular events without increasing bleeding risk in patients who had undergone intracranial stenting compared with an aspirin plus clopidogrel (aspirin-clopidogrel) regimen. This article compares the efficacy and safety outcomes of the two double antibody regimens in patients undergoing intracranial stent and investigates whether aspirin-ticagrelor could be an alternative antiplatelet agent without increasing the risk of bleeding.

Methods

We conducted a retrospective analysis of our database for patients who had undergone intracranial stenting. From January 2017 to May 2021, consecutive patients treated with endovascular stenting were identified and dichotomized by whether aspirin-ticagrelor or aspirin-clopidogrel were used. The outcomes were compared by propensity score matching.

Results

A total of 340 patients treated with intracranial stent were included. Of all, 132 patients were matched. At 180 days, ischemic vascular events occurred in one patient (1.5%) in the aspirin-ticagrelor group and in six patients (9.1%) in the aspirin-clopidogrel group. Although the absolute incidence of ischemic vascular events [1.5% (1/66) vs. 9.1% (6/66), p = 0.125] was lower in the aspirin-ticagrelor group than in the aspirin-clopidogrel group, there were no statistical differences. There were no statistical differences in ischemic vascular events, ischemic stroke, or death up to 180 days between the two groups. In addition, the incidence of bleeding did not differ. No intracranial hemorrhage or mild bleeding occurred. No statistically significant difference was noted in restenosis and symptomatic restenosis at follow-up.

Conclusion

In our study involving patients with acute ischemic stroke who had undergone intracranial stenting, aspirin-ticagrelor was not found to be superior to aspirin-clopidogrel in reducing the rate of ischemic vascular events. The risk of bleeding did not differ between the two groups. Aspirin-ticagrelor does not lower total restenosis and symptomatic restenosis risk at follow-up.

Impact of body mass index on efficacy and safety of ticagrelor versus clopidogrel in patients with minor stroke or transient ischemic attack

BACKGROUND

Body mass index (BMI) may affect the response to platelet P2Y12 receptor inhibitors. We aimed to explore whether BMI influenced the efficacy and safety of ticagrelor and clopidogrel for secondary prevention of minor ischemic stroke or transient ischemic attack (TIA) among patients enrolled in the CHANCE-2 (Ticagrelor or Clopidogrel with Aspirin in High-Risk Patients with Acute Nondisabling Cerebrovascular Events II) trial.

METHODS

In a multicentre, randomized, double-blind, placebo-controlled trial, conducted in China, we randomized patients with minor stroke or TIA who carried the CYP2C19 loss-of-function allele to receive either ticagrelor-acetylsalicylic acid (ASA) or clopidogrel-ASA. We classified patients into obese (BMI ≥ 28) or nonobese (BMI < 28) groups. The primary efficacy outcome was stroke within 90 days, and the primary safety outcome was severe or moderate bleeding within 90 days.

RESULTS

Among 6412 patients, 876 were classified as obese and 5536 were classified as nonobese. Compared with clopidogrel-ASA, ticagrelor-ASA was associated with a significantly lower rate of stroke within 90 days among patients with obesity (25 [5.4%] v. 47 [11.3%]; hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.30-0.87), but not among those in the nonobese group (166 [6.0%] v. 196 [7.0%]; HR 0.84, 95% CI 0.69-1.04) The interaction of treatment and BMI group was significant (p for interaction = 0.04). We did not observe any difference by BMI group in rates of severe or moderate bleeding (9 [0.3%] v. 10 [0.4%] in the nonobese group; 0 [0.0%] v. 1 [0.2%] in the obese group; p for interaction = 0.99).

INTERPRETATION

In this secondary analysis of a randomized controlled trial involving patients with minor ischemic stroke or TIA, compared with clopidogrel-ASA, patients with obesity received more clinical benefit from ticagrelor-ASA therapy than those without obesity.

TRIAL REGISTRATION

Clinicaltrials.gov, no. NCT04078737.

Arterial Baroreflex Dysfunction Promotes Neuroinflammation by Activating the Platelet CD40L/Nuclear Factor Kappa B Signaling Pathway in Microglia and Astrocytes

Arterial baroreflex (ABR) dysfunction has previously been associated with neuroinflammation, the most common pathological feature of neurological disorders. However, the mechanisms mediating ABR dysfunction-induced neuroinflammation are not fully understood. In the present study, we investigated the role of platelet CD40 ligand (CD40L) in neuroinflammation in an in vivo model of ABR dysfunction, and microglia and astrocyte activation in vitro. ABR dysfunction was induced in Sprague‒Dawley rats by sinoaortic denervation (SAD). We used ELSA and immunofluorescence to assess the effect of platelet CD40L on glial cell polarization and the secretion of inflammatory factors. By flow cytometry, we found that rats subjected to SAD showed a high level of platelet microaggregation and upregulation of CD40L on the platelet surface. The promotion of platelet invasion and accumulation was also observed in the brain tissues of rats subjected to SAD. In the animal model and cultured N9 microglia/C6 astrocytoma cells, platelet CD40L overexpression promoted neuroinflammation and activated M1 microglia, A1 astrocytes, and the nuclear factor kappa B (NFκB) signaling pathway. These effects were partially blocked by inhibiting platelet activity with clopidogrel or inhibiting CD40L-mediated signaling. Our results suggest that during ABR dysfunction, CD40L signaling in platelets converts microglia to the M1 phenotype and astrocytes to the A1 phenotype, activating NFκB and resulting in neuroinflammation. Thus, our study provides a novel understanding of the pathogenesis of ABR dysfunction-induced neuroinflammation and indicates that targeting platelet CD40L is beneficial for treating central nervous system (CNS) disorders associated with ABR dysfunction.

Development of a point-of-care genetic test for effective treatment of ischaemic stroke: an early model-based cost-effectiveness analysis

Background: People who have experienced a stroke are at high risk of recurrent strokes. Clopidogrel is prescribed to people who have had a non-cardioembolic stroke. There is evidence that clopidogrel is not effective for patients with CYP2C19 loss-of-function alleles. Pharmacogenetic testing is a potential strategy to identify such patients and guide prescription of appropriate antiplatelet treatment. This study aimed to provide an early estimate of the cost-effectiveness of using a point-of-care pharmacogenetic CYP2C19 test in the UK National Health System. Methods: A decision-analytic model comprising a linked decision tree and Markov model were created in R comparing pharmacogenetic testing with current prescribing practice. In the pharmacogenetic testing arm, patients identified to have one of three loss-of-function alleles were prescribed modified-release dipyridamole and aspirin or aspirin alone. Indicative data were sourced from reviews of the literature supported by expert consultation to select the most appropriate value for the input parameters. The healthcare costs (£;2021) and quality adjusted life years resulting from each strategy were estimated and the incremental cost-effectiveness of testing calculated. Deterministic threshold analysis and probabilistic sensitivity analysis (PSA) was conducted to account for uncertainty in the parameter estimates. Results: The pharmacogenetic testing strategy generated 0.107 additional QALYs per patient tested and saved £512. Pharmacogenetic testing dominated current prescribing practice. The results were robust to extreme changes in key input variables. The PSA suggested that there was a 77% chance that pharmacogenetic testing would be cost-effective with a 62% chance it is cost-saving. Conclusions: A point-of-care pharmacogenetic test to guide prescription of clopidogrel for people who have experienced a stroke has the potential to provide a significant health gain by preventing secondary strokes and may save resources in the health system. This early economic analysis has also informed the direction for future research.

Genotype-Guided Dual Antiplatelet Therapy in Minor Stroke or Transient Ischemic Attack With a Single Small Subcortical Infarction

BACKGROUND AND OBJECTIVES

Single small subcortical infarction (SSSI) is an important stroke subtype. The optimal antiplatelet medication for patients with ischemic stroke with an SSSI is still unclear. We aimed to test the efficacy and safety of ticagrelor-aspirin in preventing stroke recurrence among patients with SSSI in the Ticagrelor or Clopidogrel with Aspirin in High-Risk Patients with Acute Nondisabling Cerebrovascular Events II (CHANCE-2) trial.

METHODS

In the CHANCE-2 trial, patients with a minor stroke or TIA who carried CYP2C19 loss-of-function (LOF) alleles were randomly assigned within 24 hours after symptom onset, to either ticagrelor-aspirin (placebo clopidogrel plus a 180 mg loading dose of ticagrelor on day 1, followed by 90 mg twice daily on days 2-90) or clopidogrel-aspirin (placebo ticagrelor plus a 300 mg loading dose of clopidogrel on day 1, followed by 75 mg daily on days 2-90). Aspirin was applied during the first 21 days. Patients who had an SSSI (diffusion-weighted imaging lesion diameter ≤20 mm) were included in this analysis and further categorized into 2 types according to whether they had the responsible intracranial artery stenosis (ICAS): SSSI + ICAS and SSSI - ICAS. The primary efficacy outcome was a new stroke at 90 days.

RESULTS

Among 2,143 eligible patients, 340 had the responsible ICAS, and 1,803 did not. Ticagrelor-aspirin reduced stroke recurrence among all patients with SSSI (hazard ratio [HR]: 0.55; 95% CI 0.38-0.78; p = 0.001) compared with clopidogrel-aspirin. Stroke recurrence occurred in 35/901 (3.9%) patients with SSSI - ICAS on ticagrelor-aspirin and in 72/902 (8.0%) on clopidogrel-aspirin (hazard ratio [HR]: 0.45; 95% CI 0.29-0.68; p < 0.001). In patients with SSSI + ICAS, the corresponding event rates were 14/176 (8.0%) and 13/164 (7.9%), respectively (HR: 1.20; 95% CI 0.45-3.23; p = 0.71; p for interaction = 0.08). The risk of severe or moderate bleeding only occurred in patients with SSSI - ICAS (5/901 [0.6%] vs 5/902 [0.6%]).

DISCUSSION

In this prespecified substudy, ticagrelor-aspirin was superior to clopidogrel-aspirin in reducing the risk of stroke at 90 days among patients with SSSI who carried CYP2C19 LOF allele(s). Although there was no treatment-by-heterogeneous etiology interaction, a greater absolute risk reduction of stroke was observed in patients with SSSI - ICAS than in those with SSSI + ICAS.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that ticagrelor and aspirin reduced the risk of stroke recurrence compared with clopidogrel with aspirin in adult patients with acute minor SSSI.

Efficacy and Safety of Ticagrelor versus Aspirin and Clopidogrel for Stroke Prevention in Patients with Vascular Disease: A Systematic Review and Meta-Analysis

INTRODUCTION

Currently, it is still controversial to treat stroke with ticagrelor alone. The purpose of our study was to systematically review and analyze the efficacy and safety of ticagrelor on cerebrovascular outcomes in patients with vascular risk factors.

METHODS

The PubMed, Cochrane Library, and Embase databases were systematically searched using the keywords stroke, ticagrelor, clopidogrel, and aspirin to identify randomized controlled trials (RCTs). Primary outcomes included reported stroke, ischemic stroke, and complex events; the secondary outcome was hemorrhagic stroke. The safety outcomes included major bleeding events, major or minor bleeding, and intracranial bleeding. The pooled odds ratio (OR), hazard ratios (HRs), and 95% confidence interval (CI) were calculated. We used I2 statistics to assess statistical heterogeneity.

RESULTS

This meta-analysis included 15 RCTs involving 63,865 patients. Compared to the control group, ticagrelor reduced the risk of stroke (OR: 0.90; 95% CI: 0.81-0.99, p = 0.03; I2 = 3%), ischemic stroke (OR: 0.81; 95% CI: 0.74-0.90, p < 0.0001; I2 = 0%). Ticagrelor was not associated with an increased risk of all-cause mortality (OR: 0.94; 95% CI: 0.84-1.06, p = 0.31; I2 = 62%), major bleeding (OR: 1.06; 95% CI: 0.97-1.15, p = 0.20; I2 = 17%), hemorrhagic strokes (OR: 1.22, 95% CI: 0.76-1.96, p = 0.41; I2 = 0%), and intracranial hemorrhage (OR: 1.06; 95% CI: 0.78-1.43, p = 0.71; I2 = 12%). There was an increased risk of major or minor bleeding with ticagrelor compared to the control group (OR: 1.40; 95% CI: 1.19-1.66, p < 0.0001; I2 = 56%). Additional analyses demonstrated that ticagrelor reduced the risk of incident recurrent stroke (HR: 0.83; 95% CI: 0.75-0.93, p = 0.0009; I2 = 0%), recurrent ischemic stroke (HR: 0.79; 95% CI: 0.71-0.89, p < 0.0001; I2 = 0%) among patients with a history of acute ischemic stroke (AIS) or transient ischemic attack (TIA). There were no significant differences in safety outcomes.

CONCLUSION

Ticagrelor is slightly better than clopidogrel and aspirin in preventing stroke, especially ischemic stroke, with significant safety risks. For patients with a history of AIS/TIA, the use of ticagrelor was superior to the use of clopidogrel or aspirin in reducing the risk of subsequent stroke. We believe that ticagrelor is a potential alternative to aspirin or clopidogrel in some cases, especially for patients with CYP2C19 deficiency.

Contemporary Antiplatelet and Anticoagulant Therapies for Secondary Stroke Prevention: A Narrative Review of Current Literature and Guidelines

PURPOSE OF REVIEW

Stroke is a leading cause of death and disability worldwide. The annual incidence of new or recurrent stroke is approximately 795,000 cases per year in the United States, of which 87% are ischemic in nature. In addition to the management of modifiable high-risk factors to reduce the risk of recurrent stroke, antithrombotic agents (antiplatelets and anticoagulants) play an important role in secondary stroke prevention. This review will discuss the published literature on the use of antiplatelets and anticoagulants in secondary prevention of acute ischemic stroke and transient ischemic attack (TIA), including their pharmacology, efficacy, and adverse effects. We will also highlight the role of dual antiplatelet therapy (DAPT) in secondary stroke prevention, along with supporting literature.

RECENT FINDINGS

Single antiplatelet therapy (SAPT) with aspirin or clopidogrel reduces the risk of recurrent ischemic stroke in patients with non-cardioembolic ischemic stroke or TIA. However, as shown in recent trials, short-term DAPT with aspirin and clopidogrel or ticagrelor for 21-30 days is more effective than SAPT in patients with minor acute non-cardioembolic stroke or high-risk TIA. Although short-term DAPT is highly effective in preventing recurrent stroke, a more prolonged course can increase bleeding risks without additional benefit. DAPT for 90 days, followed by aspirin monotherapy for patients with large vessel intracranial atherosclerotic disease, is suitable for secondary stroke prevention. However, patients need to be monitored for both minor (e.g., bruising) and major (e.g., intracranial) bleeding complications. Conversely, oral warfarin and newer direct oral anticoagulant (DOACs) such as dabigatran, rivaroxaban, apixaban, and edoxaban are the agents of choice for secondary stroke prevention in patients with non-valvular cardioembolic strokes. DOACs may be preferred over warfarin due to decreased bleeding risks, including ICH, lack of need for international normalized ratio monitoring, no dietary restrictions, and limited drug-drug interactions. The choice between different antiplatelets and anticoagulants for prevention of ischemic stroke depends on the underlying stroke mechanism, cytochrome P450 2C19 polymorphisms, bleeding risk profile, compliance, drug tolerance, and drug resistance. Physicians must carefully weigh each patient's relative benefits and bleeding risks before initiating an antiplatelet/anticoagulant treatment regimen. Further studies are warranted to study the optimal duration of DAPT in symptomatic intracranial atherosclerosis since the benefit is most pronounced in the short term while the bleeding risk remains high during the extended duration of therapy.

Cost-effectiveness of testing for CYP2C19 loss-of-function carriers following transient ischemic attack/minor stroke: A Canadian perspective

BACKGROUND

The CHANCE-2 study compared 3 weeks of aspirin-ticagrelor to aspirin-clopidogrel in CYP2C19 loss-of-function (LOF) allele carriers following a transient ischemic attack (TIA)/minor stroke and demonstrated a modestly lower risk of stroke recurrence with aspirin-ticagrelor. This stroke protection was largely for minor stroke and came at an increased risk of bleeding. The cost-effectiveness of implementing testing for LOF allele status to personalize antiplatelet regimen for secondary stroke prevention after a TIA/minor stroke in the Canadian health care context is unknown.

METHODS

Cost-effectiveness analysis using a decision-analytic Markov cohort model with a lifetime horizon was performed to determine the costs and health benefits of testing for LOF allele status compared with no testing (current standard of care). The population of interest was patients living in Canada who suffered a TIA/minor stroke. Outcomes of interest were life-years gained (LYG), quality-adjusted life years (QALY) gained, costs (reported in 2022 Canadian dollars), and the incremental cost-effectiveness ratio (ICER). We adopted the perspective of the Federal, Provincial, and Territorial Ministries of Health and used a 1.5% annual discount rate. Sensitivity analyses were performed to assess uncertainty.

RESULTS

Compared to standard of care, LOF allele testing leads to 0.14 LYG (undiscounted), 0.12 QALYs gained (undiscounted), and additional lifetime costs of CAD$432 (discounted) per patient. The ICER of the LOF allele testing strategy is CAD$4310 per QALY gained compared with standard of care. The probabilistic sensitivity analyses demonstrated that LOF allele testing was cost-effective in more than 99.99% of simulations using a willingness-to-pay threshold of CAD$50,000 per QALY.

CONCLUSION

Based on available evidence, testing for LOF allele followed by short duration 3 weeks of aspirin-ticagrelor compared to standard-of-care aspirin-clopidogrel can lead to prolonged life and improved quality of life and can be considered very cost-effective when compared with other well-accepted technologies in health and medicine.

Clopidogrel Resistance and Ticagrelor Replacement in Dual Antiplatelet Therapy for Carotid Artery Stenting

BACKGROUNDS

Resistance to the pharmacological effect of clopidogrel in patients undergoing dual antiplatelet therapy for carotid stenting may increase the risk of periprocedural neurological events. The purpose of the study was to describe the phenomenon of clopidogrel resistance in a series of patients undergoing carotid stenting.

METHODS

Data of patients who consecutively underwent carotid stenting from November 2016 to December 2020 for a significant stenosis and who underwent a dual antiplatelet therapy using acetyl-salicylic acid and clopidogrel were prospectively collected. Patients who were already taking a different thienopyridine were excluded. The effectiveness of antiplatelet drugs was assessed by the impedance aggregometry test. Primary endpoint was to evaluate the incidence of clopidogrel resistance and the effectiveness of ticagrelor as alternative therapy. P values < 0.05 were considered statistically significant.

RESULTS

Two-hundred patients (80 females, 40%) underwent stenting for carotid stenosis (94% asymptomatic). The phenomenon of clopidogrel resistance was observed in 38 patients (19%), in whom clopidogrel was replaced by ticagrelor (90 mg/bis in die) with 100% effectiveness at aggregometry test. Platelet counts was associated to clopidogrel resistance (P = 0.001). There was no stent thrombosis at 30 days, neither major hemorrhagic events; a total of 12/200 major adverse cardiovascular events occurred (6%), including 1 in the group of patients who took ticagrelor and 11 in group of patients under clopidogrel (2.6% versus 6.7%, P = 0.55).

CONCLUSIONS

Clopidogrel was ineffective in 19% of patients undergoing carotid stenting. Platelet count seemed to affect this phenomenon. In these patients, clopidogrel was effectively replaced by ticagrelor.

Ticagrelor Resistance in Cardiovascular Disease and Ischemic Stroke

Ticagrelor, acting as a reversible platelet aggregation inhibitor of P2Y12 receptors (P2Y12R), is regarded as one of the first-line antiplatelet drugs for acute cardiovascular diseases. Though the probability of ticagrelor resistance is much lower than that of clopidogrel, there have been recent reports of ticagrelor resistance. In this review, we summarized the clinical application of ticagrelor and then presented the criteria and current status of ticagrelor resistance. We further discussed the potential mechanisms for ticagrelor resistance in terms of drug absorption, metabolism, and receptor action. In conclusion, the incidences of ticagrelor resistance fluctuated between 0 and 20%, and possible mechanisms mainly arose from its absorption and receptor action. Specifically, a variety of factors, such as the drug form of ticagrelor, gut microecology, and the expression and function of P-glycoprotein (P-gp) and P2Y12R, have been shown to be associated with ticagrelor resistance. The exact mechanisms of ticagrelor resistance warrant further exploration, which may contribute to the diagnosis and treatment of ticagrelor resistance.

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.

Personalized antiplatelet therapy guided by clopidogrel pharmacogenomics in acute ischemic stroke and transient ischemic attack: A prospective, randomized controlled trial

Background: Clopidogrel is frequently used in patients with ischemic stroke or transient ischemic attack (TIA), but its efficacy is hampered by inter-individual variability, due to genetic differences associated with clopidogrel metabolism. We conducted this randomized controlled trial to validate whether the personalized antiplatelet therapy based on clopidogrel pharmacogenomics and clinical characteristics leads to better clinical outcomes compared with standard treatment. Methods: Patients were randomly divided into the standard group or pharmacogenetic group, in which the pharmacogenetic group required the detection of the genotyping of CYP2C19*2, CYP2C19*3, and CYP2C19*17. Patients were followed up for 90 days for the primary efficacy endpoint of new stroke events, secondary efficacy endpoint of individual or composite outcomes of the new clinical vascular events, and the incidence of disability. The primary safety outcome was major bleeding. Results: A total of 650 patients underwent randomization, among which 325 were in the pharmacogenomics group while 325 were in the standard group. Our study found after a 90-day follow-up, the risk of stroke and composite vascular events in the pharmacogenomics group was lower than that in the standard group. The incidence of disability significantly decreased in the pharmacogenomics group. In addition, no statistically significant differences were observed in bleeding events between the two groups. Conclusion: The present study demonstrates that personalized antiplatelet therapy guided by clopidogrel pharmacogenomics and clinical characteristics can significantly improve the net clinical benefit of ischemic stroke or TIA patients during the 90-day treatment period without increasing bleeding risk.

P2Y12 Reaction Units and Clinical Outcomes in Acute Large Artery Atherosclerotic Stroke: A Multicenter Prospective Study

AIMS

We aimed to determine the association between acute platelet reactivity and clinical outcome in acute ischemic stroke (AIS) or transient ischemic attack (TIA) with large-artery atherosclerosis (LAA).

METHODS

In this prospective, 16-multicenter study, we enrolled AIS/TIA patients with LAA receiving clopidogrel. We assessed the association of P2Y12 reaction units (PRU) 24 hours after initiation of antiplatelets with the CYP2C19 genotype and recurrent ischemic stroke within 90 days, and the difference between acute (≤ 7 days) and subacute (8-90 days) phases.

RESULTS

Among the 230 AIS/TIA patients enrolled, 225 with complete outcome data and 194 with genetic results were analyzed. A higher PRU was significantly associated with recurrent ischemic stroke within 90 days (frequency, 16%), and within 7 days (10%). Twenty-nine patients (15%) belonged to a CYP2C19 poor metabolizer group (CYP2C19^＊2/^＊2, ^＊2/^＊3, or ^＊3/^＊3). Multivariable receiver-operating characteristic analysis showed a greater area-under-the-curve (AUC) in predicting recurrence within 7 days, compared to 8-90 days (AUC, 0.79 versus 0.64; p=0.07), with a cut-off PRU of 254. Multivariable analysis showed high PRU (≥ 254), which had a comparable predictive performance for recurrent ischemic stroke within 7 days (odds ratio, 6.82; 95% CI, 2.23-20.9; p＜0.001) to the CYP2C19 poor metabolizer genotype. The net reclassification improvement, calculated by adding high PRU (≥ 254) to a model including the CYP2C19 poor metabolizer genotype in the prediction of recurrence within 7 days, was 0.83 (p＜0.001).

CONCLUSIONS

Acute PRU evaluation possesses predictive value for recurrent ischemic stroke, especially within 7 days in AIS/TIA with LAA.

Genotype-Guided Dual Antiplatelet Use for Transient Ischemic Attack and Minor Stroke by Imaging Status: Subgroup Analysis of the CHANCE-2 Trial

OBJECTIVE

This study was performed to investigate whether ticagrelor/aspirin versus clopidogrel/aspirin can further reduce the residual risk of stroke recurrence in patients with positive diffusion-weighted imaging (DWI) in the High-Risk Patients with Acute Nondisabling Cerebrovascular Events II (CHANCE-2) trial.

METHODS

Patients with DWI data in the CHANCE-2 trial were included and divided into those with and without acute infarction according to their DWI findings. The primary efficacy outcome and safety outcome were stroke recurrence and moderate to severe bleeding within 3 months of follow-up, respectively.

RESULTS

Of the 6,412 patients enrolled in the CHANCE-2 trial, 5,796 (90.4%) patients with DWI data were included in the subgroup analysis. A total of 4,369 patients (75.4%) had an acute infarction on DWI. Patients with positive DWI had higher risk of recurrent stroke (8.1%) than those without infarction (2.2%) within 3-month follow-up. Compared with clopidogrel/aspirin, ticagrelor/aspirin was associated with lower risk of stroke in patients with positive DWI (hazard ratio [HR] = 0.65, 95% confidence interval [CI] = 0.52-0.80, p < 0.001) than in those negative DWI (HR = 1.22, 95% CI = 0.55-2.72, p = 0.63), with a significant interaction association (p for interaction = 0.049). The risk of moderate to severe bleeding was similar between ticagrelor/aspirin and clopidogrel/aspirin treatment in the different groups.

INTERPRETATION

Our study demonstrates that imaging evaluation should be emphasized before targeting the best candidates for genotype-guided dual antiplatelet therapy in future clinical research and practice. ANN NEUROL 2023.

DNA methylation profile in the whole blood of acute coronary syndrome patients with aspirin resistance

BACKGROUND

Aspirin resistance (AR) results in major adverse cardiovascular events, and DNA methylation might participate in the regulation of this pathological process.

METHODS

In present study, a sum of 35 patients with AR and 35 non-AR (NAR) controls were enrolled. Samples from 5 AR and 5 NAR were evaluated in an 850 BeadChip DNA methylation assay, and another 30 AR versus 30 NAR were evaluated to validate the differentially methylated CpG loci (DML). Then, qRT-PCR was used to investigate the target mRNA expression of genes at CpG loci. Finally, Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to reveal the enriched pathways.

RESULTS

The AR and NAR groups displayed significant differences in DNA methylation at 7707 positions, with 270 hypermethylated sites (e.g., cg09555818 located in APOC2) and 7437 sites hypomethylated sites (e.g., cg26828689 located in SLC12A5). Six DML were validated by pyrosequencing, and it was confirmed that DNA methylation (cg16391727, cg21008208, cg21293749, and cg13945576) was related to the increasing risk of AR. The relative mRNA expression of the ROR1 gene was also associated with AR (p = 0.007), suggesting that the change of cg21293749 in DNA methylation might lead to differential ROR1 mRNA expression, ultimately resulting in AR. Furthermore, the identified differentially methylated sites were associated with the molecular pathways such as circadian rhythms and insulin secretion.

CONCLUSION

Hence, the distinct DNA methylation might play a vital role in the biological regulation of AR through the pathways such as circadian rhythms.

Dual Antiplatelet Therapy in the Management of Acute Minor Ischemic Stroke and High-Risk Transient Ischemic Attack: An Expert Consensus Statement From Taiwan Stroke Society and Taiwan Society of Emergency Medicine

The aim of this review is to achieve a consensus between Taiwan Stroke Society (TSS) and Taiwan Society of Emergency Medicine (TSEM) to manage acute non-cardioembolic minor ischemic stroke (MIS) and high-risk transient ischemic attack (TIA). The methodology is to review the recent findings from clinical trials of dual antiplatelet therapy (DAPT) from 2010 to 2021 and updates in clinical practice guidelines from 2018 to 2022 for non-cardioembolic MIS/TIA management at the acute stage. Four leading clinical studies, CHANCE, POINT, THALES, and CHANCE-2 along with other relevant studies introducing DAPT, are discussed in this review. The risk-benefit profile between stroke recurrence reduction and major bleeding increase is also elucidated. TSS and TSEM concluded that for patients presenting with non-cardioembolic MIS or high-risk TIA who did not receive intravenous alteplase, initiation of DAPT within 24 hours after stroke onset and continued up to 21 days, followed by antiplatelet monotherapy, is effective in reducing recurrent ischemic stroke for a period of up to 90 days.

The role of CYP2C19 genotyping to guide antiplatelet therapy following ischemic stroke or transient ischemic attack

Introduction

Clopidogrel is an antiplatelet agent recommended for secondary prevention of ischemic stroke (IS) and transient ischemic attack (TIA). Conversion of clopidogrel to its active metabolite by hepatic cytochrome P450-2C19 (CYP2C19) is essential for the inhibition of the P2Y12 receptor and subsequent platelet aggregation to prevent thrombotic events. CYP2C19 is highly polymorphic, with over 30 loss of function (LoF) alleles. This review considers whether there is sufficient data to support genotype guided antiplatelet therapy after stroke.

Areas covered

A systematic literature review retrieved articles, which describe the interaction between CYP2C19 genotype and clinical outcomes following IS or TIA when treated with clopidogrel. The review documents efforts to identify optimal antiplatelet regimens and explores the value genotype guided antiplatelet therapy. The work outlines the contemporary understanding of clopidogrel metabolism and appraises evidence linking CYP2C19 LoF variants with attenuated platelet inhibition and poorer outcomes.

Expert opinion

There is good evidence that CYP2C19 LoF allele carriers of Han-Chinese ancestry have increased risk for further vascular events following TIA or IS when treated with clopidogrel. The evidence base is less certain in other populations. The expansion of pharmacogenetics into routine clinical practice will facilitate further research and help tailor other aspects of secondary prevention.

Aspirin platelet reactivity on platelet function and clinical outcome in minor stroke or transient ischemic attack

OBJECTIVE

Whether aspirin platelet reactivity affects platelet function and clinical outcomes with different antiplatelet therapies in patients with mild stroke or transient ischemic attack (TIA) remains unclear. We conducted a subgroup analysis of the PRINCE trial.

MATERIALS AND METHODS

Patients with mild stroke or TIA were randomized into aspirin+ticagrelor, or aspirin+clopidogrel groups; aspirin reaction units (ARU) were measured at the baseline and after 7 ± 2 days to assess response to treatment. High on-treatment platelet reactivity (HPR) was defined as ≥550 ARU (poor response to aspirin). The platelet functions of ticagrelor and clopidogrel were measured using the VerifyNow P2Y₁₂ assay for P2Y₁₂ reaction units (PRU); HPR to P2Y₁₂ was defined as >208 PRU (poor response to P2Y₁₂). Clinical outcomes included stroke and clinical vascular and bleeding events after 90 days.

RESULTS

Among 628 enrolled patients, 69 (11%) were poor aspirin responders. After 7 ± 2 days, the proportion of poor P2Y₁₂ responders for ticagrelor versus clopidogrel significantly reduced in poor (2.6% versus 27.4%) and good (14.3% versus 29.4%) aspirin responders. There were significant interactions between treatment groups, and between treatment groups and aspirin platelet reactivity for poor P2Y₁₂ responders (P = 0.01). After 90 ± 7 days, there were no significant interactions between treatment groups and aspirin platelet reactivity for new stroke risk (good aspirin responders: 5.5% versus 8.8%, hazard ratio [HR]: 0.61; 95% confidence interval [CI], 0.32 to 1.16; P = 0.13; poor aspirin responders: 8.6% versus 8.8%, HR: 0.97, 95% CI: 0.20-4.81; P = 0.97; P for interaction = 0.60). Major bleeding was less frequent in poor than good aspirin responders (ticagrelor/aspirin: 0.4%/0%; clopidogrel/aspirin: 1.4%/0%).

CONCLUSIONS

In patients with minor stroke or TIA, clopidogrel, and particularly ticagrelor, decreased platelet function in poor versus good aspirin responders. The poor platelet reactivity of aspirin could not sufficiently reduce the risk of recurrent stroke with ticagrelor or clopidogrel; however, HPR (poor aspirin response) may have a protective effect on clinically relevant major bleeding.

Effect of Hypertension on Efficacy and Safety of Ticagrelor-Aspirin Versus Clopidogrel-Aspirin in Minor Stroke or Transient Ischemic Attack

BACKGROUND

Hypertension is a risk factor of poor stroke outcomes and associated with antiplatelet resistance. This study aimed to explore the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in patients with different hypertension status, using randomized trial data from the CHANCE-2 trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events-II).

METHODS

A total of 6412 patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles were enrolled and randomized to either ticagrelor-aspirin or clopidogrel-aspirin group. Hypertension status were classified into no, newly diagnosed, and previously diagnosed hypertension according to medical history, blood pressure, and antihypertensive medications during hospitalization. The primary efficacy and safety outcomes were stroke recurrence and moderate to severe bleeding risk within 90-day follow-up.

RESULTS

Ticagrelor-aspirin was associated with reduced risk of new stroke in patients without hypertension (32 [4.8%] versus 60 [7.2%]; hazard ratio, 0.55 [95% CI, 0.35-0.86]), but not in those with a newly diagnosed hypertension (20 [5.3%] versus 36 [9.1%]; hazard ratio 0.59 [95% CI, 0.33-1.07]), or those with a previously diagnosed hypertension (139 [7.0%] versus 147 [7.4%]; hazard ratio, 0.93 [95% CI, 0.74-1.18]) compared with clopidogrel-aspirin (P=0.04 for interaction). The risk of bleeding for ticagrelor-aspirin was not associated with hypertension status (0.1% versus 0.4%; 0.3% versus 0.5%, 0.4% versus 0.3%, P=0.50 for interaction). All the efficacy and safety outcomes between treatments did not differ by blood pressure levels on admission.

CONCLUSIONS

In the CHANCE-2 trial, patients without hypertension received a significantly greater benefit from ticagrelor- aspirin than those with previous hypertension after minor stroke or transient ischemic attack, and a similar benefit trend was observed in those with newly diagnosed hypertension.

REGISTRATION

URL: http://www.

CLINICALTRIALS

gov; Unique identifier: NCT04078737.

Antiplatelet therapy in cardiovascular disease: Current status and future directions

Antiplatelet medications remain a cornerstone of therapy for atherosclerotic cardiovascular and cerebrovascular diseases. In primary prevention (patients with cardiovascular risk factors but no documented events, symptoms or angiographic disease), there is little evidence of benefit of any antiplatelet therapy, and such therapy carries the risk of excess bleeding. Where there is documented disease (secondary prevention), stable patients benefit from long-term antiplatelet monotherapy, aspirin being first choice in those with coronary heart disease and clopidogrel in those with cerebrovascular disease; moreover, recent evidence shows that low-dose rivaroxaban in combination with aspirin confers added benefit, in patients with stable cardiovascular and peripheral arterial disease. In patients with acute cerebrovascular disease, aspirin combined with clopidogrel reduces subsequent risk, while in acute coronary syndrome, dual antiplatelet therapy comprising aspirin and a P2Y12 inhibitor (clopidogrel, prasugrel or ticagrelor) confers greater protection than aspirin monotherapy, with prasugrel and ticagrelor offering greater antiplatelet efficacy with faster onset of action than clopidogrel. Although greater antiplatelet efficacy is advantageous in preventing thrombotic events, this must be tempered by increased risk of bleeding, which may be a particular issue in certain patient groups, as will be discussed. We will also discuss possible future approaches to personalisation of antiplatelet therapy.

Effect of CYP2C19 genetic polymorphism on the pharmacodynamics and clinical outcomes for patients treated with ticagrelor: a systematic review with qualitative and quantitative meta-analysis

BACKGROUND

Studies show inconsistent results regarding the impact of CYP2C19 genotype on the pharmacodynamics (PD) and clinical outcomes of ticagrelor. With the implementation of genotype-guided individualized antiplatelet therapy, the association between CYP2C19 polymorphism and the efficacy and safety of ticagrelor for patients is still worthy of exploring and studying.

METHODS

This systematic review protocol has been registered in the PROSPERO network (No. CRD 42020158920). Electronic databases of PubMed, EmBase, and the Cochrane Library were systematically searched from inception to January 6th, 2022 to select studies investigating the impact of CYP2C19 genotype on PD and clinical outcomes of ticagrelor. The results were presented as odds ratio (OR) or weight mean difference with its 95% confidence interval (CI) by using the random-effects model. Trial sequential analysis (TSA) was used to control risk of random errors and detect the robustness of outcomes.

RESULTS

Eight studies recruited a total of 6405 patients treated with ticagrelor. Mostly trials reported no significant effect of any or no CYP2C19 loss-of-function (LOF) allele (*2 or *3) on all the endpoints. Compared with no LOF allele carriers, subgroup analysis suggested any LOF allele in Asian patients was associated with a significant decreased risk of bleeding events (OR: 0.41; 95% CI: 0.22-0.75; P = 0.004). Furthermore, any LOF allele carriers didn't yield any impact on the risk of MACEs (OR: 1.11; 95% CI: 0.76-1.64; P = 0.586), stroke (OR: 1.71; 95% CI: 0.99-2.96; P = 0.054), definite stent thrombosis (OR: 0.88; 95% CI: 0.17-4.60; P = 0.882), bleeding (OR: 0.63; 95% CI: 0.27-1.46; P = 0.281), myocardial infarction (OR: 0.81; 95% CI: 0.30-2.20; P = 0.682), and revascularization (OR: 0.81; 95% CI: 0.33-2.00; P = 0.649) in all patients. The results of TSA were indicated that more further trials would be required.

CONCLUSIONS

This qualitative and quantitative study suggested Asian patients carrying any CYP2C19 LOF allele might have a lower risk of bleeding events comparing with no LOF allele carriers when treated with ticagrelor. However, we did not prove an important role of CYP2C19 genotype on the risk of PD and clinical endpoints in the whole cohort. In future, more large-scale prospective studies and more different ethnic populations should be included.

Relationship between platelet aggregation and stroke risk after percutaneous coronary intervention: a PENDULUM analysis

In patients undergoing percutaneous coronary intervention (PCI) with a stent, high on-treatment platelet reactivity may be associated with an increased risk of stroke. This post hoc analysis of the PENDULUM registry compared the risk of post-PCI stroke according to on-treatment P2Y₁₂ reaction unit (PRU) values. Patients aged ≥ 20 years who underwent PCI were stratified by baseline PRU (at 12 and 48 h post-PCI) as either high (HPR, > 208), optimal (OPR, > 85 to ≤ 208), or low on-treatment platelet reactivity (LPR, ≤ 85). The incidences of non-fatal ischemic and non-ischemic stroke through to 12 months post-PCI were recorded. Almost all enrolled patients (6102/6267 [97.4%]) had a risk factor for ischemic stroke, and most were receiving dual antiplatelet therapy. Of the 5906 patients with PRU data (HPR, n = 2227; OPR, n = 3002; LPR, n = 677), 47 had a non-fatal stroke post-PCI (cumulative incidence: 0.68%, ischemic; 0.18%, non-ischemic stroke). Patients with a non-fatal ischemic stroke event had statistically significantly higher post-PCI PRU values versus those without an event (P = 0.037). The incidence of non-fatal non-ischemic stroke was not related to PRU value. When the patients were stratified by PRU ≤ 153 versus > 153 at 12–48 h post-PCI, a significant difference was observed in the cumulative incidence of non-fatal stroke at 12 months (P = 0.044). We found that patients with ischemic stroke tended to have higher PRU values at 12–48 h after PCI versus those without ischemic stroke.

Clinical trial registration: UMIN000020332.

Ticagrelor versus Clopidogrel in CYP2C19 Loss-of-Function Carriers with Stroke or TIA

BACKGROUND

Comparisons between ticagrelor and clopidogrel for the secondary prevention of stroke in CYP2C19 loss-of-function carriers have not been extensively performed.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial at 202 centers in China involving patients with a minor ischemic stroke or transient ischemic attack (TIA) who carried CYP2C19 loss-of-function alleles. Patients were assigned within 24 hours after symptom onset, in a 1:1 ratio, to receive ticagrelor (180 mg on day 1 followed by 90 mg twice daily on days 2 through 90) and placebo clopidogrel or to receive clopidogrel (300 mg on day 1 followed by 75 mg once daily on days 2 through 90) and placebo ticagrelor; both groups received aspirin for 21 days. The primary efficacy outcome was new stroke, and the primary safety outcome was severe or moderate bleeding, both within 90 days.

RESULTS

A total of 11,255 patients were screened and 6412 patients were enrolled, with 3205 assigned to the ticagrelor group and 3207 to the clopidogrel group. The median age of the patients was 64.8 years, and 33.8% were women; 98.0% belonged to the Han Chinese ethnic group. Stroke occurred within 90 days in 191 patients (6.0%) in the ticagrelor group and 243 patients (7.6%) in the clopidogrel group (hazard ratio, 0.77; 95% confidence interval, 0.64 to 0.94; P = 0.008). Secondary outcomes were generally in the same direction as the primary outcome. Severe or moderate bleeding occurred in 9 patients (0.3%) in the ticagrelor group and in 11 patients (0.3%) in the clopidogrel group; any bleeding occurred in 170 patients (5.3%) and 80 patients (2.5%), respectively.

CONCLUSIONS

Among Chinese patients with minor ischemic stroke or TIA who were carriers of CYP2C19 loss-of-function alleles, the risk of stroke at 90 days was modestly lower with ticagrelor than with clopidogrel. The risk of severe or moderate bleeding did not differ between the two treatment groups, but ticagrelor was associated with more total bleeding events than clopidogrel. (Funded by the Ministry of Science and Technology of the People's Republic of China and others; CHANCE-2 ClinicalTrials.gov number, NCT04078737.).

Bleeding Risk of Dual Antiplatelet Therapy after Minor Stroke or TIA

OBJECTIVE

To identify the risk of bleeding events and potential risk factors within 90 days in patients carried CYP2C19 loss-of-function alleles and received dual antiplatelet therapy after minor stroke or transient ischemic attack.

METHODS

A total of 6,412 patients were enrolled from the Clopidogrel with aspirin in High-risk patients with Acute Non-disabling Cerebrovascular Events II (CHANCE-2) trial. The main outcome was any bleeding within 90 days defined by the criteria from Global Utilisation of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO).

RESULTS

A total of 250 (3.9%) bleeding events were reported, which occurred mainly within the 21 days of dual antiplatelet therapy (200 cases, 3.1%). Minor bleeding of the skin bruises, epistaxis, and gum bleeding was most frequent. Multivariate analysis showed that treatment with ticagrelor-aspirin compared with clopidogrel-aspirin was associated with increased bleeding (hazard ratio [HR], 2.21; 95% confidence interval [CI], 1.68-2.89; P<0.001). Current smoking was associated with a lower risk of bleeding (HR, 0.70; 95% CI, 0.52-0.95; P=0.02). Additionally, ticagrelor-aspirin compared with clopidogrel-aspirin was associated with higher risk of bleeding in patients aged <65 years (HR, 2.87; 95% CI, 1.95-4.22) and those without diabetes mellitus (HR, 2.65; 95% CI, 1.88-3.73) (P for interaction=0.04 and 0.03, respectively).

INTERPRETATION

Bleeding events mostly occurred within the 21-day dual antiplatelet therapy stage and were generally mild. The risk of bleeding was greater in non-smoking patients, and was associated with treatment with ticagrelor-aspirin compared with clopidogrel-aspirin particularly in aged <65 years and non-diabetic patients. This article is protected by copyright. All rights reserved.

Clopidogrel Versus Ticagrelor for Antiplatelet Therapy in Transcarotid Artery Revascularization (TCAR) in the Society for Vascular Surgery Vascular Quality Initiative

OBJECTIVE

Transcarotid artery revascularization (TCAR) with dynamic flow reversal is a hybrid technique for operative management of carotid artery stenosis. Dual antiplatelet therapy is recommended for patients undergoing TCAR; however, nonresponders to these medications may be predisposed to perioperative thromboembolic complications. Prevalent in up to 44-66% of patients taking clopidogrel, high on-treatment platelet reactivity (HTPR) may thus be responsible for a portion of adverse cerebrovascular events in TCAR. A previous single-institution study has demonstrated the use of ticagrelor as a viable alternative to clopidogrel for antiplatelet therapy in patients undergoing TCAR; however, large-scale comparisons between clopidogrel and ticagrelor are needed to confirm the safety of ticagrelor outside of highly selected patients and providers.

METHODS

Data from patients enrolled in the Society for Vascular Surgery Vascular Quality Initiative undergoing TCAR with a perioperative antiplatelet therapy regimen including either clopidogrel or ticagrelor from January 2015 to March 2021 were analyzed and compared. Multivariable logistic regression and propensity score matching were used to evaluate the primary 30-day outcomes of stroke, major bleeding event, and combined stroke/myocardial infarction (MI)/death rate while adjusting for baseline characteristics of the patients.

RESULTS

A total of 11973 patients underwent TCAR with a dual antiplatelet therapy regimen that included clopidogrel versus 426 patients with ticagrelor. Compared to clopidogrel, patients on ticagrelor were significantly more likely to have coronary artery disease (51% vs 66% [P = <.001]), particularly unstable angina or MI within 6 months (3% vs 9% [P = <.001]), and more likely to have insulin-dependent diabetes mellitus (14% vs 19% [P = <.001]). The unadjusted 30-day rates of stroke, major bleeding, and combined stroke/MI/death were not statistically significant among both groups (1.3% vs 0.5% [P = .14], 2.4% vs 1.4% [P = .18], and 1.9% vs 1.6% [P = .71], respectively). After multivariable adjustment and propensity matching, these remained statistically insignificant.

CONCLUSIONS

Despite a substantially higher medical risk in patients undergoing TCAR with ticagrelor, 30-day rates of stroke, major bleeding events, and combined stroke/MI/death were similar between patients on ticagrelor and clopidogrel as part of adjunctive antiplatelet therapy. Randomized prospective trials, and studies with larger sample sizes and longer follow-up will be needed to better examine the outcome differences in TCAR between these two medications.

Comparison of Ticagrelor vs Clopidogrel in Addition to Aspirin in Patients With Minor Ischemic Stroke and Transient Ischemic Attack: A Network Meta-analysis

Importance

Dual antiplatelet therapy (DAPT) with clopidogrel and aspirin is effective in preventing recurrent strokes after minor ischemic stroke or transient ischemic attack (TIA). However, there is emerging evidence for the use of ticagrelor and aspirin, and the 2 DAPT regimens have not been compared directly.

Objective

To compare ticagrelor and aspirin with clopidogrel and aspirin in patients with acute minor ischemic stroke or TIA in the prevention of recurrent strokes or death.

Data Sources

MEDLINE, Embase, and Cochrane from database inception until February 2021.

Study Selection

Randomized clinical trials that enrolled adults with acute minor ischemic stroke or TIA and provided the mentioned interventions within 72 hours of symptom onset, with a minimum follow-up of 30 days.

Data Extraction and Synthesis

PRISMA guidelines for network meta-analyses were followed. Two reviewers independently extracted data and appraised risk of bias. Fixed-effects models were fit using a bayesian approach to network meta-analysis. Between-group comparisons were estimated using hazard ratios (HRs) with 95% credible intervals (95% CrIs). Surface under the cumulative rank curve plots were produced.

Main Outcomes and Measures

The primary outcome was a composite of recurrent stroke or death up to 90 days. Secondary outcomes include major bleeding, mortality, adverse events, and functional disability. A sensitivity analysis was performed at 30 days for the primary outcome.

Results

A total of 4014 citations were screened; 5 randomized clinical trials were included. Data from 22 098 patients were analyzed, including 5517 in the clopidogrel and aspirin arm, 5859 in the ticagrelor and aspirin arm, and 10 722 in the aspirin arm. Both clopidogrel and aspirin (HR, 0.74; 95% CrI, 0.65-0.84) and ticagrelor and aspirin (HR, 0.79; 95% CrI, 0.68-0.91) were superior to aspirin in the prevention of recurrent stroke and death. There was no statistically significant difference between clopidogrel and aspirin compared with ticagrelor and aspirin (HR, 0.94; 95% CrI, 0.78-1.13). Both DAPT regimens had higher rates of major hemorrhage than aspirin alone. Clopidogrel and aspirin was associated with a decreased risk of functional disability compared with aspirin alone (HR, 0.82; 95% CrI, 0.74-0.91) and ticagrelor and aspirin (HR, 0.85; 95% CrI, 0.75-0.97).

Conclusions and Relevance

DAPT combining aspirin with either ticagrelor or clopidogrel was superior to aspirin alone, but there was no statistically significant difference found between the 2 regimens for the primary outcome.

Benefits and risks of antiplatelet medication in hemodynamically stable adult moyamoya disease

Revascularization surgery is considered a standard treatment for preventing additional stroke in symptomatic moyamoya disease (MMD). In hemodynamically stable, and asymptomatic or mildly symptomatic patients, however, the treatment strategy is controversial because of the obscure natural course of them. The authors analyzed the benefits and risks of antiplatelet medication in those patients. Medical data were retrospectively reviewed in 439 hemispheres of 243 patients with stable hemodynamic status. Overall, 121 patients (49.8%) with 222 studied hemispheres (50.6%) took antiplatelet medication. Symptomatic cerebral infarction and hemorrhage occurred in 10 (2.3%) and 30 (6.8%) hemispheres, over a mean follow-up of 62.0 ± 43.4 months (range 6-218 months). The use of antiplatelet agents was statistically insignificant in terms of symptomatic infarction, hemorrhage and improvement of ischemic symptoms. In subgroup analyses within the antiplatelet group according to drug potency and duration of medication, a longer duration of antiplatelet medication significantly improved ischemic symptoms (adjusted OR 1.02; 95% CI 1.01-1.03; p = 0.006). Antiplatelet medication failed to prevent symptomatic cerebral infarction or improve ischemic symptoms. However, antiplatelet therapy did not increase the risk of cerebral hemorrhage.