The diversity and clinical implications of genetic variants influencing clopidogrel bioactivation and response in the Emirati population.

BACKGROUND: Clopidogrel is a widely prescribed prodrug that requires activation via specific pharmacogenes to exert its anti-platelet function. Genetic variations in the genes encoding its transporter, metabolizing enzymes, and target receptor lead to variability in its activation and platelet inhibition and, consequently, its efficacy. This variability increases the risk of secondary cardiovascular events, and therefore, some variations have been utilized as genetic biomarkers when prescribing clopidogrel. METHODS: Our study examined clopidogrel-related genes (CYP2C19, ABCB1, PON1, and P2Y12R) in a cohort of 298 healthy Emiratis individuals. The study used whole exome sequencing (WES) data to comprehensively analyze pertinent variations of these genes, including their minor allele frequencies, haplotype distribution, and their resulting phenotypes. RESULTS: Our data shows that approximately 37% (n = 119) of the cohort are likely to benefit from the use of alternative anti-platelet drugs due to their classification as intermediate or poor CYP2C19 metabolizers. Additionally, more than 50% of the studied cohort exhibited variants in ABCB1, PON1, and P2YR12 genes, potentially influencing clopidogrel's transport, enzymatic clearance, and receptor performance. CONCLUSIONS: Recognizing these alleles and genotype frequencies may explain the clinical differences in medication response across different ethnicities and predict adverse events. Our findings underscore the need to consider genetic variations in prescribing clopidogrel, with potential implications for implementing personalized anti-platelet therapy among Emiratis based on their genetic profiles.

Low-dose aspirin for the prevention of atherosclerotic cardiovascular disease.

During the past 30 years, several developments have occurred in the antiplatelet field, including the role of aspirin in primary prevention of atherosclerotic cardiovascular disease. There have been several attempts to develop antiplatelet drugs more effective and safer than aspirin and a shift in emphasis from efficacy to safety, advocating aspirin-free antiplatelet regimens after percutaneous coronary intervention. Evidence supporting a chemopreventive effect of low-dose aspirin against colorectal (and other digestive tract) cancer has also strengthened. The aim of this article is to revisit the role of aspirin in the prevention of atherothrombosis across the cardiovascular risk continuum, in view of developments in the antiplatelet field. The review will offer a clinical perspective on aspirin's mechanism of action, pharmacokinetics, and pharmacodynamics. This will be followed by a detailed discussion of its clinical efficacy and safety.

Aspirin-free antiplatelet strategies after percutaneous coronary interventions.

Dual antiplatelet therapy (DAPT) with aspirin and a platelet P2Y12 receptor inhibitor is the standard antithrombotic treatment after percutaneous coronary interventions (PCI). Several trials have challenged guideline-recommended DAPT after PCI by testing the relative clinical effect of an aspirin-free antiplatelet approach-consisting of P2Y12 inhibitor monotherapy after a short course (mostly 1-3 months) of DAPT-among patients undergoing PCI without a concomitant indication for oral anticoagulation (OAC). Overall, these studies have shown P2Y12 inhibitor monotherapy after short DAPT to be associated with a significant reduction in the risk of bleeding without an increase in thrombotic or ischaemic events compared with continued DAPT. Moreover, the effects of the P2Y12 inhibitor monotherapy without prior DAPT or following a very short course of DAPT after PCI are being investigated in emerging studies, of which one has recently reported unfavourable efficacy results associated with the aspirin-free approach compared with conventional DAPT. Finally, P2Y12 inhibitor alone has been compared with aspirin alone as chronic therapy after DAPT discontinuation, thus challenging the historical role of aspirin as a standard of care for secondary prevention following PCI. A thorough understanding of study designs, populations, treatments, results, and limitations of trials testing P2Y12 inhibitor monotherapy vs. DAPT or vs. aspirin is required to consider adopting this treatment in clinical practice. This review addresses the use of aspirin-free antiplatelet strategies among patients undergoing PCI without a concomitant indication for OAC, providing an overview of clinical evidence, guideline indications, practical implications, ongoing issues, and future perspectives.

Rivaroxaban Plus Aspirin Versus Aspirin Alone After Endovascular Revascularization for Symptomatic PAD: Insights From VOYAGER PAD.

BACKGROUND: Rivaroxaban plus aspirin compared with aspirin alone reduced major cardiac and ischemic limb events after lower extremity revascularization (LER) in the VOYAGER PAD (Vascular Outcomes Study of ASA Along With Rivaroxaban in Endovascular or Surgical Limb Revascularization for Peripheral Artery Disease) trial. The effect has not been described in patients undergoing endovascular LER. METHODS: The VOYAGER PAD trial randomized 6564 patients with symptomatic peripheral artery disease to a double-blinded treatment with 2.5 mg of rivaroxaban BID or matching placebo and 100 mg of aspirin daily. The primary efficacy outcome was a composite of acute limb ischemia, major amputation of a vascular pathogenesis, myocardial infarction, ischemic stroke, or cardiovascular death. The principal safety end point was Thrombolysis in Myocardial Infarction major bleeding. A prespecified subgroup of patients who underwent endovascular revascularization was included. RESULTS: Endovascular LER occurred in 4379 (66.7%) patients and surgical LER in 2185 (33.3%). Over a 3-year follow-up, rivaroxaban reduced the risk of the primary outcome by 15% (hazard ratio [HR], 0.85 [95% CI, 0.76-0.96]) with an absolute risk reduction of 0.92% at 6 months and 1.04% at 3 years and a consistent benefit in those receiving endovascular (HR, 0.89 [95% CI, 0.76-1.03]) or surgical LER (HR, 0.81 [95% CI, 0.67-0.98]; P interaction=0.43). For endovascular-treated patients, rivaroxaban reduced the risk of acute limb ischemia or major amputation of a vascular pathogenesis by 30% (HR, 0.70 [95% CI, 0.54-0.90]; P=0.005) with an absolute risk reduction of 1.0% at 6 months and 2.0% at 3 years compared with aspirin alone. Among endovascular-treated patients, the median duration of concomitant dual antiplatelet therapy with clopidogrel treatment was 31 days (interquartile range, 30-58). There was a consistent benefit for rivaroxaban regardless of background clopidogrel. Thrombolysis in Myocardial Infarction major bleeding was significantly higher for the rivaroxaban and aspirin group for the endovascular cohort (HR, 1.66 [95% CI, 1.06-2.59]) with an absolute risk increase of 0.9% at 3 years with no increase in intracranial or fatal bleeding observed (HR, 0.86 [95% CI, 0.40-1.87]; P=0.71). Mortality with rivaroxaban was higher in the endovascular-treated patients (HR, 1.24 [95% CI, 1.02-1.52]), although this finding was isolated to specific regions. CONCLUSIONS: Rivaroxaban added to aspirin or dual antiplatelet therapy after LER for peripheral artery disease reduces ischemic risk and increases major bleeding without an increased risk of intracranial or fatal bleeding. These benefits are consistent in those treated with endovascular and surgical approaches with significant benefits for major adverse limb events. These data support the use of rivaroxaban in addition to aspirin or dual antiplatelet therapy after endovascular intervention for symptomatic peripheral artery disease.

Pharmacogenomic evaluation of CYP2C19 alleles linking low clopidogrel response and the risk of acute coronary syndrome in Indians.

BACKGROUND: Clopidogrel is an antiplatelet drug widely prescribed to prevent atherothrombotic events in coronary artery disease patients. However, there is evidence to suggest that the effectiveness of clopidogrel varies owing to genetic diversity in CYP2C19. This heterogeneity in South Asians, who are also known to have high risk of cardiac events than other population groups, highlights the importance of investigating CYP2C19 variants to estimate the risk proportion in the groups. METHODS: Given the high prevalence and genetic heterogeneity, the population-based case control was conducted in a cohort of 1191 subjects comprising 645 acute coronary syndrome (ACS) cases (unstable angina, ST-elevation myocardial infarction, and non-ST-elevation myocardial infarction) and 546 healthy controls of South Asian Indian origin. The metabolization status of CYP2C19 was assessed using *2, *3 and *17 variants in the stated cohorts to determine the prevalence of metabolization and its association with phenotypes. RESULTS: The results suggest a possible genetic association between studied CYP2C19 polymorphisms and ACS, since there was a higher proportion of intermediate and poor metabolizers present in the studied cohorts. The association analyses revealed that the *2 allele of CYP2C19 confers a significant risk for ACS, while the *17 allele provides protection. CONCLUSIONS: These findings contribute to the understanding of CYP2C19 genetic variants and their impact on clopidogrel response in South Asian Indians. Additionally, they underline the significance of assessing CYP2C19 variations in patients receiving clopidogrel therapy in order to improve therapeutic outcomes.

Impact of proton pump inhibitor use on clinical outcomes in East Asian patients receiving clopidogrel following drug-eluting stent implantation.

BACKGROUND: Concomitant use of clopidogrel and proton pump inhibitor (PPI) is common, but PPI may reduce the antiplatelet effects of clopidogrel in patients undergoing percutaneous coronary intervention (PCI). We evaluated the impact of PPI use on clinical outcomes in post-PCI patients, by incorporating P2Y12 reaction unit (PRU) and CYP2C19 genotyping results. METHODS: From a multicenter registry of patients who underwent PCI with drug-eluting stent implantation and received clopidogrel-based dual antiplatelet therapy (DAPT), patients who were prescribed a PPI at the time of PCI (PPI users) were compared to those who were not (non-users). The primary outcome included all-cause death, myocardial infarction, stent thrombosis, or cerebrovascular accident at 12 months. Major bleeding (Bleeding Academic Research Consortium [BARC] types 3-5) and gastrointestinal (GI) bleeding (BARC types 3-5) were important secondary outcomes. The adjusted outcomes were compared using a 1:1 propensity-score (PS) matching and competing risk analysis. RESULTS: Of 13,160 patients, 2,235 (17.0%) were prescribed PPI, with an average age of 65.4 years. PPI users had higher on-treatment PRU levels than non-users. After PS matching, the primary outcome occurred in 51 patients who were PPI users (cumulative incidence, 4.7%) and 41 patients who were non-users (cumulative incidence, 3.7%; log-rank p = 0.27). In carriers of both CYP2C19 loss-of-function alleles, PPI use was linked to an increased risk of the primary outcome (hazard ratio, 3.22; 95% confidence interval, 1.18-8.78). The incidence of major bleeding and GI bleeding (BARC types 3-5) was comparable between PPI users and non-users in the PS-matched cohort. CONCLUSIONS: In post-PCI patients receiving clopidogrel-based DAPT, PPI use was not linked to an increased risk of adverse cardiac and cerebrovascular events, but there was a small but significant increase in on-treatment PRU. Future research using a more individualized approach would further elucidate these interactions and guide evidence-based clinical practices.

Precision medicine in cardiovascular therapeutics: Evaluating the role of pharmacogenetic analysis prior to drug treatment.

Pharmacogenomics is the examination of how genetic variation influences drug metabolism and response, in terms of both efficacy and safety. In cardiovascular disease, patient-specific diplotypes determine phenotypes, thereby influencing the efficacy and safety of drug treatments, including statins, antiarrhythmics, anticoagulants and antiplatelets. Notably, polymorphisms in key genes, such as CYP2C9, CYP2C19, VKORC1 and SLCO1B1, significantly impact the outcomes of treatment with clopidogrel, warfarin and simvastatin. Furthermore, the CYP2C19 polymorphism influences the pharmacokinetics and safety of the novel hypertrophic cardiomyopathy inhibitor, mavacamten. In this review, we critically assess the clinical application of pharmacogenomics in cardiovascular disease and delineate present and future utilization of pharmacogenomics. This includes insights into identifying missing heritability, the integration of whole genome sequencing and the application of polygenic risk scores to enhance the precision of personalized drug therapy. Our discussion encompasses health economic analyses that underscore the cost benefits associated with pre-emptive genotyping for warfarin and clopidogrel treatments, albeit acknowledging the need for further research in this area. In summary, we contend that cardiovascular pharmacogenomic analyses are underpinned by a wealth of evidence, and implementation is already occurring for some of these gene-drug pairs, but as with any area of medicine, we need to continually gather more information to optimize the use of pharmacogenomics in clinical practice.

Economic evaluation of pharmacogenomic-guided antiplatelet treatment in Spanish patients suffering from acute coronary syndrome participating in the U-PGx PREPARE study.

BACKGROUND: Cardiovascular diseases and especially Acute Coronary Syndrome (ACS) constitute a major health issue impacting millions of patients worldwide. Being a leading cause of death and hospital admissions in many European countries including Spain, it accounts for enormous amounts of healthcare expenditures for its management. Clopidogrel is one of the oldest antiplatelet medications used as standard of care in ACS. METHODS: In this study, we performed an economic evaluation study to estimate whether a genome-guided clopidogrel treatment is cost-effective compared to conventional one in a large cohort of 243 individuals of Spanish origin suffering from ACS and treated with clopidogrel. Data were derived from the U-PGx PREPARE clinical trial. Effectiveness was measured as survival of individuals while study data on safety and efficacy, as well as on resource utilization associated with each adverse drug reaction were used to measure costs to treat these adverse drug reactions. A generalized linear regression model was used to estimate cost differences for both study groups. RESULTS: Based on our findings, PGx-guided treatment group is cost-effective. PGx-guided treatment demonstrated to have 50% less hospital admissions, reduced emergency visits and almost 13% less ADRs compared to the non-PGx approach with mean QALY 1.07 (95% CI, 1.04-1.10) versus 1.06 (95% CI, 1.03-1.09) for the control group, while life years for both groups were 1.24 (95% CI, 1.20-1.26) and 1.23 (95% CI, 1.19-1.26), respectively. The mean total cost of PGx-guided treatment was 50% less expensive than conventional therapy with clopidogrel [€883 (95% UI, €316-€1582), compared to €1,755 (95% UI, €765-€2949)]. CONCLUSION: These findings suggest that PGx-guided clopidogrel treatment represents a cost-effective option for patients suffering from ACS in the Spanish healthcare setting.

The pharmaco-epigenetics of hypertension: a focus on microRNA.

Hypertension is a major harbinger of cardiovascular morbidity and mortality. It predisposes to higher rates of myocardial infarction, chronic kidney failure, stroke, and heart failure than most other risk factors. By 2025, the prevalence of hypertension is projected to reach 1.5 billion people. The pathophysiology of this disease is multifaceted, as it involves nitric oxide and endothelin dysregulation, reactive oxygen species, vascular smooth muscle proliferation, and vessel wall calcification, among others. With the advent of new biomolecular techniques, various studies have elucidated a gaping hole in the etiology and mechanisms of hypertension. Indeed, epigenetics, DNA methylation, histone modification, and microRNA-mediated translational silencing appear to play crucial roles in altering the molecular phenotype into a hypertensive profile. Here, we critically review the experimentally determined associations between microRNA (miRNA) molecules and hypertension pharmacotherapy. Particular attention is given to the epigenetic mechanisms underlying the physiological responses to antihypertensive drugs like candesartan, and other relevant drugs like clopidogrel, aspirin, and statins among others. Furthermore, how miRNA affects the pharmaco-epigenetics of hypertension is especially highlighted.

Cost-effectiveness analysis of CYP2C19 genotype-guided antiplatelet therapy for patients with acute minor ischemic stroke and high-risk transient ischemic attack in China.

AIMS: The study aimed to estimate the cost-effectiveness of CYP2C19 genotype-guided antiplatelet therapy using cilostazol and ticagrelor as an alternative to clopidogrel, compared to conventional antiplatelet therapy with clopidogrel and aspirin. METHODS: A 90-day decision tree and 30-year Markov model were employed to assess the costs and quality-adjusted life years (QALYs) of personalized antiplatelet therapy for patients with minor ischemic stroke and high-risk transient ischemic attack, compared to conventional antiplatelet therapy in the Chinese healthcare system. The primary outcome was the incremental cost-effectiveness ratio (ICER). The data sources included clinical trials, published literature, official documents and local prices. One-way sensitivity analysis and probabilistic sensitivity analysis were performed to confirm the robustness of the findings. RESULTS: The base-case analysis indicated that the CYP2C19 genotype-guided antiplatelet strategy was cost-effective, and cilostazol group and ticagrelor group yielded an ICER of 3327.40 US dollars (USD)/QALY and 3426.92 USD/QALY, respectively, which were less than threshold. The one-way sensitivity analysis showed the results were robust, where the most sensitive parameter was the disability distribution in the modified Rankin scale 3-5. The probabilistic analysis showed that the CYP2C19 genotype-guided antiplatelet therapy with either cilostazol or ticagrelor was 100% cost-effective under the willingness-to-pay threshold. CONCLUSIONS: CYP2C19 genotype-guided antiplatelet therapy using cilostazol and ticagrelor as an alternative to clopidogrel appeared to be more cost-effective than conventional antiplatelet therapy for acute minor ischemic stroke and high-risk transient ischemic attack patients over 30 years in China.

The association between abcb1 gene polymorphism and clopidogrel response variability in stroke ischemic: a cross sectional study.

BACKGROUND: Clopidogrel has been the primary choice of antiplatelet in ischemic stroke that inhibits adenosine diphosphate (ADP)-induced platelet aggregation. P-glycoprotein (P-gp) multidrug resistance-1 (MDR1) is a transmembrane efflux transporter in intestinal cells that plays a significant role in clopidogrel absorption, therefore may affect platelet aggregation. P-gp is encoded by the ABCB1 gene. This study aims to evaluate the effect of ABCB1 polymorphism on clopidogrel response variability in ischemic stroke patients and its genotype frequency. METHODS: A cross-sectional study was conducted in ischemic stroke patients who received clopidogrel between 2020 and 2023 in RSUI/RSCM. All subjects were assessed for ABCB1 polymorphisms C3435T and C1236T. Platelet aggregation were measured using VerifyNow PRU. Clopidogrel response variability was classified into unresponsive (> 208 PRU), responsive (95-208 PRU), and bleeding risk (< 95 PRU). RESULTS: 124 subjects enrolled in this study, with 12,9% of subjects classified as non-responsive/resistant, 49,5% as responsive, and 41,9% as bleeding risk. ABCB1 C1236T homozygote wildtype (CC) was associated with 3,76 times higher bleeding risk than other variants (p = 0,008; 95%CI 1,41 - 10,07). Genotype frequency of ABCB1 C3435T homozygote wildtype, heterozygote, and homozygote variants were 35,9%, 43,5% and 16,9%, respectively; while the genotype frequency of ABCB1 C1236T were 17,8%, 39,5%, and 42,7%, respectively. CONCLUSION: ABCB1 C1236T homozygote wildtype was associated with 3,76 times higher bleeding risk than other variants. The most common genotype frequency of ABCB1 C1236T was homozygote variant; while for ABCB1 C3435T was heterozygote.

Efficacy and safety of aspirin plus clopidogrel versus aspirin alone in ischemic stroke or high-risk transient ischemic attack: A meta-analysis of randomized controlled trials.

Background: Antiplatelet therapy plays an important role in reducing the risk of stroke recurrence in patients with mild ischemic stroke or high-risk transient ischemic attack (TIA). However, data regarding the effectiveness and safety of using aspirin plus clopidogrel in dual antiplatelet therapy (DAPT) compared to aspirin alone in mild ischemic stroke is limited. Methods: PubMed/MEDLINE, Embase, Cochrane Library, and ClinicalTrials.gov were searched for randomized controlled trials (RCTs) that compared DAPT to aspirin alone started within 72 hours in mild ischemic stroke or high-risk TIA. We used a random effects model to pool risk ratios (RRs) along with 95% CIs for clinical outcomes. Results: Four RCTs with 16,547 patients were included in this study. DAPT significantly reduced the risk of recurrent stroke by 26% (RR: 0.74; 95% CI: 0.67-0.83; p < 0.00001), ischemic stroke by 28% (RR: 0.72; 95% CI: 0.65-0.80; p < 0.00001), and major adverse cardiovascular events (MACE) by 24% (RR: 0.76; 95% CI: 0.68-0.84; p < 0.00001) compared to aspirin monotherapy. However, DAPT was associated with a significantly increased risk of moderate or severe bleeding (RR: 1.88; 95% CI: 1.10-3.23; p = 0.02) compared to aspirin alone. No significant differences were observed for hemorrhagic stroke (RR: 1.77; 95% CI: 0.96-3.29; p = 0.07), all-cause mortality (RR: 1.25; 95% CI: 0.87-1.80; p = 0.23), cardiovascular mortality (RR: 1.38; 95% CI: 0.81-2.33; p = 0.23), and myocardial infarction (RR: 1.63; 95% CI: 0.77-3.46; p = 0.20). Conclusion: DAPT involving aspirin plus clopidogrel reduces stroke recurrence and MACE but can lead to an increased risk of moderate or severe bleeding compared to aspirin monotherapy. (PROSPERO ID: CRD42024499310).

Comparison of Heart Rates in Patients Initiated on Ticagrelor Versus Other P2Y12 Inhibitors After an Inferior ST Elevation Myocardial Infarction (STEMI).

BACKGROUND: P2Y12 inhibitors have differing associations of bradyarrhythmias. Ticagrelor has been shown to increase adenosine plasma concentrations leading to increases in bradyarrhythmias. While clopidogrel and prasugrel have not been shown to have any association with bradyarrhythmias. OBJECTIVE: The objective of this study was to determine heart rates after ticagrelor initiation compared to clopidogrel/prasugrel in inferior ST Elevation Myocardial Infarction (STEMI) patients. METHODS: This was a retrospective, multicenter study conducted at 3 primary percutaneous coronary intervention (PCI) centers between January 1, 2017 and September 30, 2022. Adult patients were included if they were diagnosed with an inferior STEMI to the right coronary artery (RCA) and treated with PCI followed by an oral P2Y12 inhibitor. The primary outcome was heart rate at 48 hours or discharge, whichever first, after administration of ticagrelor compared to clopidogrel/prasugrel. RESULTS: This study reviewed 331 patients, 172 in the ticagrelor group and 159 in the clopidogrel/prasugrel group. There were no statistical differences between groups regarding the primary outcome, with a median heart rate of 76 beats per minute (bpm) [67-85] in the ticagrelor group versus 73 bpm [66-84] in the clopidogrel/prasugrel group (P = 0.238). No differences were observed between groups regarding any secondary outcomes. CONCLUSION AND RELEVANCE: There were similar heart rates between ticagrelor and clopidogrel/prasugrel. There were also similarities in the ability to tolerate beta-blocker therapy after initiation of a P2Y12 inhibitor. The results of this study suggest that in inferior STEMIs when using ticagrelor as the P2Y12 inhibitor, there are not increased clinical manifestations of bradycardia.

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

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

Comparison of Ticagrelor with Clopidogrel on Coronary Microvascular Dysfunction Following Acute Myocardial Infarction Using Angiography-Derived Index of Microcirculatory Resistance.

PURPOSE: This research aimed to assess the impact of ticagrelor and clopidogrel on coronary microvascular dysfunction (CMD) and prognosis following acute myocardial infarction (AMI), using the angiography-derived index of microcirculatory resistance (angio-IMR) as a non-invasive assessment tool. METHODS: In this retrospective study, angio-IMR was performed to evaluate CMD before and after dual antiplatelet therapy (DAPT) with either ticagrelor (90 mg twice daily, n = 184) or clopidogrel (75 mg once daily, n = 72). The primary endpoint is the improvement of CMD evaluated by angio-IMR (delta angio-IMR) following DAPT. Secondary endpoints included myocardial reinfarction and readmission for heart failure during 2-year follow-up. RESULTS: Compared with clopidogrel, ticagrelor exhibited a significantly higher delta angio-IMR [- 3.09 (5.14) versus - 1.99 (1.91), P = 0.008], indicating a superior improvement of CMD with ticagrelor treatment. Multivariate Cox regression indicated that ticagrelor treatment was related to a reduced risk of readmission for heart failure [8 (4.3) versus 9 (12.5), adjusted HR = 0.329; 95% CI = 0.116-0.934; P = 0.018] and myocardial reinfarction [7 (3.8) versus 8 (11.1), adjusted HR = 0.349; 95% CI = 0.125-0.975; P = 0.026]. Furthermore, ticagrelor treatment serves as an independent predictor of readmission for heart failure (HR = 0.322; 95% CI = 0.110-0.943; P = 0.039). CONCLUSION: The results of this study indicate a potential association between ticagrelor treatment and improved CMD, as well as a reduced risk of cardiovascular events, including myocardial reinfarction and readmission for heart failure in AMI patients. Further randomized controlled trials are necessary to confirm the potential benefits of ticagrelor on CMD and cardiovascular prognosis. This clinical trial was registered in www. CLINICALTRIALS: gov (NCT05978726).

The Impact of CYP2C19 Genotype on the Platelet Reactivity Index (PRI) among Chronic Coronary Syndromes (CCS) Patients Undergoing Percutaneous Coronary Intervention (PCI): Affectability of Rapid Genetic Testing.

BACKGROUND: In the Asian population, the presence of the CYP2C19 loss-of-function (LOF) allele is a known genetic variation. This allele is associated with a reduced capacity to metabolize clopidogrel into its active forms through the CYP2C19 enzyme, resulting in diminished platelet inhibition and an elevated risk of recurrent cardiovascular events. Regulatory authorities have recommended an alternative P2Y12 inhibitor, ticagrelor, for individuals carrying the LOF allele. Consequently, this study seeks to assess the impact of the CYP2C19 genotype on the Platelet reactivity index (PRI) using a rapid genetic testing approach in Asian patients with chronic coronary syndromes (CCS) who undergo percutaneous coronary intervention (PCI). METHODS: This prospective study employed a parallel design, single-center design, and randomized approach. Genotyping for the CYP2C19*2 and *3 polymorphisms was conducted using the Nested Allele-Specific Multiplex PCR (NASM-PCR) technique. Patients meeting the inclusion criteria underwent genotyping for CYP2C19 polymorphisms. Following PCI, patients were randomly assigned to receive either ticagrelor or clopidogrel. PRI assessments were performed four hours after loading dose administration. The trial was registered with ClinicalTrials.gov under the identifier NCT05516784. RESULTS: Among the 94 patients recruited for the study, 40 (42.55%) were identified as carriers of the LOF allele for CYP2C19*2 and *3 (*1/*2, *2/*2, *1/*3). Out of the 84 patients evaluated for PRI (44 receiving clopidogrel and 40 receiving ticagrelor), 21 (47.7%) of the clopidogrel group and 39 (97.5%) of the ticagrelor group exhibited a favorable response to antiplatelet therapy (PRI < 50). Patients treated with ticagrelor demonstrated superior antiplatelet responses compared to those receiving clopidogrel, regardless of LOF carrier status (P = 0.005 and < 0.001 for non-LOF and LOF carriers, respectively). CONCLUSION: NASM-PCR as a rapid genetic test holds promise for personalizing antiplatelet therapy in Asian CCS patients.

Comparison of ticagrelor and clopidogrel in anemic patients with acute coronary syndrome: efficacy and safety outcomes over one year.

OBJECTIVE: This retrospective study aimed to investigate the potential impact of ticagrelor and clopidogrel treatment on cardiovascular outcomes in patients with anemia and acute coronary syndrome (ACS) and to provide insights into the optimal therapeutic approach for this vulnerable patient population. METHODS: A retrospective research design was employed, involving patients diagnosed with ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI) between 2014 and 2021. Inclusion criteria required a hemoglobin level below 12 mg/dL and a minimum 12-month P2Y12 inhibitor treatment. Comprehensive clinical, biochemical, and echocardiographic data were collected from the hospital's electronic repository. The primary efficacy endpoint was major adverse cardiovascular events (MACE), encompassing total mortality, cardiovascular mortality, reinfarction, ischemic stroke, and hemorrhagic stroke. Major hemorrhage was the primary safety endpoint. Secondary outcomes included total mortality, cardiovascular mortality, reinfarction, ischemic stroke, and hemorrhagic stroke, individually. RESULTS: Patients treated with ticagrelor (n = 118) and clopidogrel (n = 538) were compared. No significant difference was observed in major adverse cardiovascular events (MACE) and major bleeding between ticagrelor and clopidogrel treatment groups (MACE: clopidogrel 10.0% vs. ticagrelor 11.0%, p = 0.75; major bleeding: clopidogrel 2.8%, ticagrelor 2.5%, p = 0.88). Patients with hemoglobin levels ≤ 8 mg/dL demonstrated significantly higher MACE and major bleeding rates in the ticagrelor group (p = 0.008 and p = 0.002, respectively). Among patients aged ≥ 75 years, ticagrelor treatment was associated with a higher risk of major bleeding (p = 0.04). CONCLUSIONS: Ticagrelor and clopidogrel exhibited comparable efficacy and safety outcomes in anemic ACS patients over a one-year period. Although ticagrelor demonstrated superiority in reducing ischemic events, it is crucial to recognize the limitations of retrospective studies in informing clinical practice. This study offers valuable insights into tailoring antiplatelet therapy for anemic ACS patients and provides guidance for personalized treatment strategies, acknowledging the hypothesis-generating nature of retrospective analyses.

Effect of ticagrelor versus clopidogrel after implantation of drug-eluting stents guided by either intravascular ultrasound or angiography in patients with acute coronary syndrome-propensity score matching analysis.

BACKGROUND: The effect of different dual antiplatelet therapies on thrombotic events on the background of intravascular ultrasound (IVUS) guidance is unclear. We investigated whether ticagrelor can provide any additional benefit to clopidogrel in reducing thrombotic events in acute coronary syndrome (ACS) treated with drug- eluting stent (DES), when guided by IVUS or not. METHODS: A total of 5,666 ACS patients who underwent DES implantation and who were discharged on dual antiplatelet therapy were enrolled and grouped according to the use of IVUS or not. Each group was subdivided into two subgroups according to the type of P2Y12 inhibitor used after discharge. Propensity score matching (PSM) was used between the IVUS and no-IVUS groups. Covariate adjustment of Cox proportional hazards model was used between the ticagrelor and clopidogrel groups. Thrombotic event at 12 months was compared in groups separately. RESULTS: After PSM, 12-month follow-up data were available for 1,174 patients. Major adverse cardiac events (MACE) were less frequent in the IVUS-guided group (2.2% vs. 4.3%, P = 0.081) with a trend toward statistical significance. Comparison of antiplatelet regimens revealed significantly fewer major adverse cardiac and cerebrovascular events (MACCE) with ticagrelor in the entire PSM cohort and angiography-guided subgroup (2.9% vs. 5.7%, P = 0.035; 3.1% vs. 6.4%, P = 0.020, respectively). Among patients in the IVUS-guided group the outcome was comparable (2.5% vs. 4.4%, P = 0.312). Ticagrelor was associated with increasing bleeding incidence in the entire PSM cohort (1.3% vs. 3.3%, P = 0.030), mainly due to Bleeding Academic Research Consortium type 2 bleeding (0.7% vs. 2.6%, P = 0.010). The results were consistent after covariate adjustment of Cox proportional hazards model. CONCLUSION: The comparison of ischemic benefit between ticagrelor and clopidogrel was similar in patients receiving IVUS guidance during stent implantation, probably due to the precise implantation of IVUS. Multicenter, randomized studies should be performed to validate this conclusion.

Temporal trends in use of antisecretory agents among patients administered clopidogrel-based dual antiplatelet therapy after percutaneous coronary intervention.

BACKGROUND: Antisecretory drugs are commonly prescribed with clopidogrel-based dual antiplatelet therapy (DAPT) to prevent gastrointestinal bleeding in high-risk patients after percutaneous coronary intervention (PCI). However, omeprazole and esomeprazole (inhibiting proton pump inhibitors [PPIs]) may increase cardiovascular event rates on co-administration with clopidogrel. This study aimed to examine trends in the use of antisecretory agents in patients administered clopidogrel-based DAPT and the concomitant use of clopidogrel and inhibiting PPIs. METHODS: We used National Inpatient Sample data compiled by the Health Insurance Review & Assessment Service from 2009 to 2020. Further, we identified patients who were prescribed clopidogrel-based DAPT after PCI and investigated the concomitant use of antisecretory agents with clopidogrel. To verify the annual trend of drug utilization, we used the Cochran-Armitage trend test. RESULTS: From 2009 to 2020, the percentage of H2 receptor antagonist users decreased steadily (from 82.5% in 2009 to 25.3% in 2020); instead, the percentage of PPI users increased (from 23.7% in 2009 to 82.0% in 2020). The use of inhibiting PPI also increased (from 4.2% in 2009 to 30.7% in 2020). Potassium competitive acid blockers (P-CABs) were rarely used before 2019; however, in 2020, it accounted for 7.8% of the antisecretory users. CONCLUSIONS: Our study demonstrates that the use of inhibiting PPIs increased steadily in patients administered clopidogrel-based DAPT therapy. This is a major concern since the concomitant use of inhibiting PPIs with clopidogrel could increase the risk of cardiovascular events.

Development of a routine bedside CYP2C19 genotype assessment program for antiplatelet therapy guidance in a community hospital catheterization laboratory.

Genotype based personalized antiplatelet therapy in the setting of percutaneous coronary intervention (PCI) has been studied in clinical trials. Despite the demonstrated risk associated with CYP2C19 loss-of-function (LoF) carriage in clopidogrel-treated PCI patients, real-world implementation of genotyping for PCI has been low. The goal of the current study was to provide CYP2C19 genotype information to the interventionalist prior to the completion of the catheterization to facilitate immediate personalized antiplatelet therapy. Routine personalization of P2Y12 inhibitor therapy for PCI in a community hospital cardiac catheterization laboratory by POC genotyping with the SpartanRx system was first offered in February 2017. A best practice advisory (BPA) based on the Clinical Pharmacogenetics Implementation Consortium Guideline for CYP2C19 genotype and clopidogrel therapy was placed in the electronic health record prescription medication ordering system. By December 2019, 1,052 patients had CYP2C19 genotype testing, 429 patients underwent PCI with genotype guided antiplatelet therapy, and 250 patients underwent PCI without genotype testing and received antiplatelet therapy at the discretion of the treating physician. BPA compliance was 93. 87% of LoF allele carriers were prescribed ticagrelor or prasugrel whereas 96% of non-LoF allele carriers were prescribed clopidogrel. The genotyping results were available within 1 h and made immediately available for decision making by the interventional cardiologist. POC CYP2C19 genotyping is feasible in a community hospital catheterization laboratory and is associated with high rate of best practice compliance.Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03040622.