Point of care CYP2C19 genotyping after percutaneous coronary intervention.

Loss-of-function CYP2C19 variants are associated with increased cumulative ischemic outcomes warranting CYP2C19 genotyping prior to clopidogrel administration. TAILOR-PCI was an international, multicenter (40 sites), prospective, randomized trial comparing rapid point of care (POC) genotype-guided vs. conventional anti-platelet therapy. The performance of buccal-based rapid CYP2C19 genotyping performed by non-laboratory-trained staff in TAILOR-PCI was assessed. Pre-trial training and evaluation involved rapid genotyping of 373 oral samples, with 99.5% (371/373) concordance with Sanger sequencing. During TAILOR-PCI, 5302 patients undergoing PCI were randomized to POC rapid CYP2C19 *2, *3, and *17 genotyping versus no genotyping. At 12 months post-PCI, TaqMan genotyping determined 99.1% (2,364/2,385) concordance with the POC results, with 90.7-98.8% sensitivity and 99.2-99.6% specificity. In conclusion, non-laboratory personnel can be successfully trained for on-site instrument operation and POC rapid genotyping with analytical accuracy and precision across multiple international centers, thereby supporting POC genotyping in patient-care settings, such as the cardiac catheterization laboratory.Clinical Trial Registration: https://www.clinicalTrials.gov (Identifier: NCT01742117).

Dual antiplatelet therapy (PEGASUS) vs. dual pathway (COMPASS): a head-to-head in vitro comparison.

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor is prescribed for 1-year after myocardial infarction. Two clinical strategies are considered at 1-year: continuation of DAPT or "Dual Pathway" (DP), using aspirin and rivaroxaban. No head-to-head comparative studies exist. In our in-vitro study, 24 samples of donor blood were treated with clinically proven concentrations of 5 antithrombotic regimens: aspirin, ticagrelor, rivaroxaban, DAPT, and DP. Thrombosis was analyzed using the Total Thrombus Analysis System (T-TAS) to measure both antiplatelet and anticoagulant effects. Flow cytometry was performed to quantify platelet activation. DAPT was the most potent antiplatelet regimen, delaying thrombus onset (p < .0001) and reducing thrombogenicity (p < .0001), relative to control. DP did not delay thrombus formation relative to aspirin alone (p = .69). DP was the most potent anticoagulant regimen, delaying thrombus onset (p < .0001) and reducing thrombogenicity (p < .0001), relative to control. DP showed synergistic antithrombotic effects by delaying thrombus onset (p < .0001) and reducing thrombogenicity (p = .0003), relative to rivaroxaban alone. Flow cytometry showed only DAPT (p = .0023) reduced platelet activation. DP treatment demonstrated synergistic antithrombotic effects over rivaroxaban alone, but no additional antiplatelet synergism over aspirin alone.

International Expert Consensus on Switching Platelet P2Y12 Receptor-Inhibiting Therapies.

Dual antiplatelet therapy with aspirin and a P2Y12 inhibitor is the treatment of choice for the prevention of atherothrombotic events in patients with acute coronary syndromes and for those undergoing percutaneous coronary interventions. The availability of different oral P2Y12 inhibitors (clopidogrel, prasugrel, ticagrelor) has enabled physicians to contemplate switching among therapies because of specific clinical scenarios. The recent introduction of an intravenous P2Y12 inhibitor (cangrelor) further adds to the multitude of modalities and settings in which switching therapies may occur. In clinical practice, it is not uncommon to switch P2Y12 inhibitor, and switching may be attributed to a variety of factors. However, concerns about the safety of switching between these agents have emerged. Practice guidelines have not fully elaborated on how to switch therapies, leaving clinicians with limited guidance on when and how to switch therapies when needed. This prompted the development of this expert consensus document by key leaders from North America and Europe with expertise in basic, translational, and clinical sciences in the field of antiplatelet therapy. This expert consensus provides an overview of the pharmacology of P2Y12 inhibitors, different modalities and definitions of switching, and available literature and recommendations for switching between P2Y12 inhibitors.

P2Y12 receptor inhibitor resistance and coronary artery disease: a bench to bedside primer for cardiovascular specialists.

PURPOSE OF REVIEW: Platelet P2Y12 receptor inhibitors are routinely prescribed for patients after acute coronary syndromes and percutaneous coronary interventions. Patients may have underresponsiveness (or resistance) to these drugs and in particular to clopidogrel, the most often used type. This review aims to focus on the concept of P2Y12 receptor inhibitor resistance and discuss incidence, mechanisms, novel diagnostic techniques and past and future clinical trials on the topic. RECENT FINDINGS: Patients treated with P2Y12 receptor inhibitors may develop high on-treatment platelet reactivity (HPR), a phenomenon of impaired response toward the drug, which has been associated with ischemic complications. Although potent P2Y12 inhibitors provide better ischemic protection, this must be balanced with increased bleeding risk. Several clinical factors, including common genetic variants such as Cytochrome P450 2C19 loss-of-function alleles, have been shown to predispose to HPR among patients on clopidogrel. Platelet function tests and genotyping platforms have enabled identification of patients at-risk for HPR. Past studies using platelet testing and tailoring therapy among patients with HPR have failed to provide conclusive data to support its routine use. SUMMARY: Ongoing studies using genotyping and novel antiplatelet regimens may identify potential strategies to minimize ischemic and bleeding risks concurrently. Until definitive studies demonstrate clear benefit of a personalized approach to P2Y12 inhibitor prescription, the choice of P2Y12 inhibitors should continue to be based on best evidence from previous large clinical trials.

Interhospital Variation in Admissions Managed With Critical Care Therapies or Invasive Hemodynamic Monitoring in Tertiary Cardiac Intensive Care Units: An Analysis From the Critical Care Cardiology Trials Network Registry.

BACKGROUND: Wide interhospital variations exist in cardiovascular intensive care unit (CICU) admission practices and the use of critical care restricted therapies (CCRx), but little is known about the differences in patient acuity, CCRx utilization, and the associated outcomes within tertiary centers. METHODS: The Critical Care Cardiology Trials Network is a multicenter registry of tertiary and academic CICUs in the United States and Canada that captured consecutive admissions in 2-month periods between 2017 and 2022. This analysis included 17 843 admissions across 34 sites and compared interhospital tertiles of CCRx (eg, mechanical ventilation, mechanical circulatory support, continuous renal replacement therapy) utilization and its adjusted association with in-hospital survival using logistic regression. The Pratt index was used to quantify patient-related and institutional factors associated with CCRx variability. RESULTS: The median age of the study population was 66 (56-77) years and 37% were female. CCRx was provided to 62.2% (interhospital range of 21.3%-87.1%) of CICU patients. Admissions to CICUs with the highest tertile of CCRx utilization had a greater burden of comorbidities, had more diagnoses of ST-elevation myocardial infarction, cardiac arrest, or cardiogenic shock, and had higher Sequential Organ Failure Assessment scores. The unadjusted in-hospital mortality (median, 12.7%) was 9.6%, 11.1%, and 18.7% in low, intermediate, and high CCRx tertiles, respectively. No clinically meaningful differences in adjusted mortality were observed across tertiles when admissions were stratified by the provision of CCRx. Baseline patient-level variables and institutional differences accounted for 80% and 5.3% of the observed CCRx variability, respectively. CONCLUSIONS: In a large registry of tertiary and academic CICUs, there was a >4-fold interhospital variation in the provision of CCRx that was primarily driven by differences in patient acuity compared with institutional differences. No differences were observed in adjusted mortality between low, intermediate, and high CCRx utilization sites.

Point-of-care genetic testing for personalisation of antiplatelet treatment (RAPID GENE): a prospective, randomised, proof-of-concept trial.

BACKGROUND: Prospective assessment of pharmacogenetic strategies has been limited by an inability to undertake bedside genetic testing. The CYP2C19*2 allele is a common genetic variant associated with increased rates of major adverse events in individuals given clopidogrel after percutaneous coronary intervention (PCI). We used a novel point-of-care genetic test to identify carriers of the CYP2C19*2 allele and aimed to assess a pharmacogenetic approach to dual antiplatelet treatment after PCI. METHODS: Between Aug 26, 2010, and July 7, 2011, 200 patients were enrolled into our prospective, randomised, proof-of-concept study. Patients undergoing PCI for acute coronary syndrome or stable angina were randomly assigned to rapid point-of-care genotyping or to standard treatment. Individuals in the rapid genotyping group were screened for the CYP2C19*2 allele. Carriers were given 10 mg prasugrel daily, and non-carriers and patients in the standard treatment group were given 75 mg clopidogrel daily. The primary endpoint was the proportion of CYP2C19*2 carriers with high on-treatment platelet reactivity (P2Y12 reactivity unit [PRU] value of more than 234) after 1 week of dual antiplatelet treatment, which is a marker associated with increased adverse cardiovascular events. Interventional cardiologists and data analysts were masked to genetic status and treatment. Patients were not masked to treatment allocation. All analyses were by intention to treat. This study is registered with ClinicalTrials.gov, NCT01184300. FINDINGS: After randomisation, 187 patients completed follow-up (91 rapid genotyping group, 96 standard treatment). 23 individuals in each group carried at least one CYP2C19*2 allele. None of the 23 carriers in the rapid genotyping group had a PRU value of more than 234 at day 7, compared with seven (30%) given standard treatment (p=0·0092). The point-of-care genetic test had a sensitivity of 100% (95% CI 92·3-100) and a specificity of 99·3% (96·3-100). INTERPRETATION: Point-of-care genetic testing after PCI can be done effectively at the bedside and treatment of identified CYP2C19*2 carriers with prasugrel can reduce high on-treatment platelet reactivity. FUNDING: Spartan Biosciences.

The association of PRECISE-DAPT score with ischaemic outcomes in patients taking dual antiplatelet therapy following percutaneous coronary intervention: a meta-analysis.

AIMS: The PRECISE-DAPT (Predicting Bleeding Complication in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet Therapy) score identifies patients at high risk of bleeding complications following percutaneous coronary intervention (PCI). International guidelines recommend the PRECISE-DAPT score to identify patients at high risk for bleeding, who may benefit from shortened dual antiplatelet therapy. The association of the PRECISE-DAPT score with ischaemic outcomes remains unclear. We performed a meta-analysis investigating the association between a high PRECISE-DAPT score and ischaemic outcomes. METHODS AND RESULTS: A comprehensive literature search was conducted on articles published between 11 March 2017 and 5 June 2021. Two reviewers independently screened articles for inclusion using pre-defined criteria. The outcome measures extracted included composite ischaemic events, major bleeding events, and all-cause mortality. A random effects model was applied to obtain combined risk estimates for outcomes. From 12 included studies, there were 39 459 patients with PRECISE-DAPT <25 and 14 761 patients with PRECISE-DAPT ≥25. PRECISE-DAPT score ≥25 was associated with increased risk of composite ischaemic events [odds ratio (OR) 2.16; 95% confidence interval (CI) 1.77-2.65], myocardial infarction (OR 2.06; 95% CI 1.38-3.08), and ischaemic stroke (OR 2.90; 95% CI 1.76-4.78). Patients with a PRECISE-DAPT score ≥25 had increased risk of major bleeding (OR 3.62; 95% CI 2.62-4.99). Patients with a PRECISE-DAPT score ≥25 had higher risk of all-cause mortality (OR 5.83; 95% CI 5.37-6.33). CONCLUSION: Patients with a PRECISE-DAPT score ≥25 are at increased risk for ischaemic events, bleeding, and all-cause mortality. Prospective evaluation of a PRECISE-DAPT guided approach to antiplatelet therapy is required to demonstrate benefit in this high-risk population.

Sex-Specific Differences in Clinical Outcomes After Percutaneous Coronary Intervention: Insights from the TAILOR-PCI Trial.

Background TAILOR-PCI (Tailored Antiplatelet Initiation to Lessen Outcomes due to decreased Clopidogrel Response After Percutaneous Coronary Intervention) studied genotype-guided selection of antiplatelet therapy after percutaneous coronary intervention versus conventional therapy with clopidogrel. The presence of CYP2C19 loss-of-function alleles in patients treated with clopidogrel may be associated with increased risk for ischemic events. We report a prespecified sex-specific analysis of genotyping and associated cardiovascular outcomes from this study. Methods and Results Associations between sex and major adverse cardiac events (MACE: cardiovascular death, myocardial infarction, stroke, stent thrombosis, and severe recurrent ischemia) and Bleeding Academic Research Consortium (BARC) bleeding at 12 months were analyzed using Cox proportional-hazards models. Among 5276 randomized patients, loss-of-function carriers were observed in ≈36% of both sexes, and >80% of carriers were heterozygotes. At 12 months, after adjustment for baseline differences, risks of MACE (HR , 1.28 [0.97 to 1.68]; P=0.088) and BARC bleeding (hazard ratio [HR], 1.36 [0.91 to 2.05]; P=0.14) were comparable among women and men. There were no significant interactions between sex and treatment strategy for MACE interaction P value (Pint=0.59) or BARC bleeding (Pint=0.47) nor for sex and genotype (MACE Pint=0.15, and BARC bleeding Pint=0.60). Conclusions CYP2C19 loss-of-function alleles were present in ≈1 in 3 women and men. Women had similar adjusted risks of MACE and bleeding as men following percutaneous coronary intervention. Genotype-guided therapy did not significantly reduce the risk of MACE or bleeding relative to conventional therapy for both sexes. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01742117.

Implications of the Antiplatelet Therapy Gap Left With Discontinuation of Prasugrel in Canada.

BACKGROUND: The current Canadian Cardiovascular Society antiplatelet therapy guidelines recommend the use of ticagrelor or prasugrel over clopidogrel as first-line platelet P2Y12 receptor antagonists for treatment of moderate- to high-risk acute coronary syndromes. Recently, Effient (prasugrel [Eli Lilly Canada Inc, Toronto, Canada]) was discontinued by its distributor in Canada. METHODS: Five members of the Canadian Cardiovascular Society antiplatelet therapy 2018 guidelines committee undertook an independent, evidence-based review to outline patients for whom prasugrel should be the optimal P2Y12 agent and discuss alternative strategies to consider without prasugrel. RESULTS: Several clinical scenarios where prasugrel should be indicated are identified and discussed. Considerations to be undertaken for alternative therapies are summarized, including a review of national and international guidelines for de-escalation of P2Y12 receptor antagonists. CONCLUSIONS: The discontinuation of prasugrel poses a challenge for clinicians. Clinicians must consider key factors in determining the best alternate therapy.

INTRODUCTION: Dans ses lignes directrices actuelles sur la thérapie antiplaquettaire, la Société canadienne de cardiologie recommande l'utilisation du ticagrélor ou du prasugrel plutôt que l'utilisation du clopidogrel comme antagonistes des récepteurs plaquettaires P2Y12 de première intention dans le traitement des patients qui présentent un risque modéré à élevé de syndromes coronariens aigus. Depuis peu, le distributeur a cessé la distribution d'Effient (prasugrel) au Canada. MÉTHODES: Cinq membres du comité des lignes directrices 2018 sur la thérapie antiplaquettaire de la Société canadienne de cardiologie ont entrepris une revue indépendante fondée sur les données probantes pour dresser le profil des patients pour lesquels le prasugrel devrait être la meilleure option parmi les antagonistes des récepteurs P2Y12 et se pencher sur les traitements alternatifs en l'absence de prasugrel. RÉSULTATS: Plusieurs scénarios cliniques où le prasugrel devrait être indiqué sont recensés et abordés. Les réflexions sur les solutions de rechange au traitement, notamment une revue des lignes directrices nationales et internationales en matière de désescalade des antagonistes des récepteurs P2Y12, sont présentées. CONCLUSIONS: La cessation de la distribution du prasugrel pose problème aux cliniciens. Les cliniciens doivent tenir compte des facteurs clés pour déterminer le meilleur traitement de remplacement.

Outcomes in Patients Stratified by PRECISE-DAPT Versus DAPT Scores After Percutaneous Coronary Interventions.

The optimal length of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) remains debated. Current guidelines recommend individualized treatment with consideration of risk scores. We sought to evaluate the degree of agreement in treatment recommendations and the ability to predict ischemic and bleeding complications of the PRECISE-DAPT (predicting bleeding complications in patients undergoing stent implantation and subsequent dual antiplatelet therapy) and DAPT scores. Consecutive patients receiving 12 months of DAPT were grouped based on score treatment recommendation at the time of PCI: PRECISE-DAPT prolonged or shortened (PRECISE DAPT <25 vs ≥25) and DAPT prolonged or shortened (DAPT ≥2 vs <2). One-year ischemic and bleeding outcomes were compared for each group. In 451 patients, the PRECISE-DAPT and DAPT score recommendations were concordant in 56.7% of patients (Cohen's kappa for agreement of k = 0.139, 95% confidence interval 0.065 to 0.212). There was no difference in composite major adverse cardiovascular and cerebrovascular events between patients with high versus low PRECISE-DAPT or DAPT scores. In patients with a high PRECISE-DAPT score versus a low score, there was an increased incidence of 1-year all-cause mortality (2.13% vs 0%, p = 0.04) and an increase in bleeding (Bleeding Academic Research Consortium ≥3a: 17.0% vs 2.8%; p <0.001; Bleeding Academic Research Consortium 3b/c and 5: 8.5% vs 1.4%; p = 0.001). There were no differences in rates of mortality or bleeding for patients with high versus low DAPT scores. In conclusion, when applied at the baseline, the PRECISE-DAPT and DAPT scores frequently make discordant DAPT duration recommendations. The PRECISE-DAPT, but not the DAPT score, demonstrated associations with all-cause mortality and bleeding in patients prescribed 12 months of DAPT after PCI.

Colchicine for Prevention of Atherothrombotic Events in Patients With Coronary Artery Disease: Review and Practical Approach for Clinicians.

A better understanding of the central role of inflammation in the development of coronary artery disease (CAD) has been the impetus for the evaluation of therapeutic strategies targeting the interleukin-1ß/interleukin-6 cytokine signaling pathway, involved in both chronic atherogenesis and in triggering of atherosclerotic plaque rupture. As an inexpensive pharmacologic agent with relatively few adverse effects that tend to be mild and tolerable, the role of colchicine in secondary prevention of atherothrombotic events has been the focus of multiple recent large-scale randomized controlled trials involving patients with stable CAD (Low-Dose Colchicine [LoDoCo] and LoDoCo2 trials), a recent myocardial infarction (Colchicine Cardiovascular Outcome Trial [COLCOT], Colchicine in Patients With Acute Coronary Syndrome [COPS], and Colchicine and Spironolactone in Patients With Myocardial Infarction/Synergy Stent Registry [CLEAR SYNERGY] trials), and undergoing percutaneous coronary interventions (Colchicine in Percutaneous Coronary Intervention [COLCHICINE-PCI] trial). Based on this evidence, low-dose colchicine (0.5 mg once daily) should be considered in patients with recent myocardial infarctions-within 30 days and, ideally, within 3 days-or with stable CAD to improve cardiovascular outcomes. Colchicine should not be used in patients with severe renal or hepatic disease because of the risk of severe toxicity. No serious adverse effect was associated with the combined use of colchicine and high-intensity statin therapy in large trials. The impact of colchicine in high-risk populations of patients with peripheral arterial disease and in those with diabetes for the primary prevention of CAD remains to be established.

Antithrombotic Therapy After Percutaneous Coronary Intervention in Patients With Atrial Fibrillation: Findings From the CONNECT AF+PCI Study.

BACKGROUND: In patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI), selecting an antithrombotic regimen requires balancing risks of ischemic cardiac events, stroke, and bleeding. METHODS: We studied 467 patients with AF undergoing PCI in the time period from December 2015 to July 2018 identified via a chart audit by 47 Canadian cardiologists in the CONNECT AF+PCI (the Coordinated National Network to Engage Interventional Cardiologists in the Antithrombotic Treatment of Patients With Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) study, to determine patterns of initial antithrombotic therapy selection. RESULTS: The median (25th, 75th percentile) CHADS2 score was 2 (1, 3), and PCI was performed in the setting of acute coronary syndrome in 62.1%. Triple antithrombotic therapy (TAT) was the initial treatment in 62.7%, dual-pathway therapy in 25.7%, and dual antiplatelet therapy in 11.6%, with a temporal increase in use of dual-pathway therapy during the course of the study; median intended TAT duration was 1 (1, 3) month. Compared with patients selected for TAT, patients selected for dual-pathway therapy were less likely to have prior myocardial infarction (35.8% vs 25.8%, P = 0.045) and prior PCI (33.8% vs 23.3%, P = 0.03), and they received shorter total length of stents (38 [23, 56] vs 30 [20, 46] mm, P = 0.03). Patients selected for dual-pathway therapy had a higher prevalence of prior stroke/transient ischemic attack (13.0% vs 23.3%, P = 0.01). There was no difference in prevalence of anemia (21.5% vs 25.8%, P = 0.30). Use of dual-pathway therapy was similar among patients with acute coronary syndrome and those with stable disease (24.1% vs 28.2%, P = 0.32). CONCLUSIONS: Approximately one-quarter of AF patients undergoing PCI are treated with dual-pathway therapy in Canadian practice, with its use increasing during the studied period. Patients selected for dual-pathway therapy have less-complex coronary disease history and intervention.

INTRODUCTION: Les patients atteints de fibrillation auriculaire (FA) qui subissent une intervention coronarienne percutanée (ICP) et choisissent un schéma posologique antithrombotique ont besoin de peser les risques d'événements cardiaques d'origine ischémique, d'accidents vasculaires cérébraux et d'hémorragies. MÉTHODES: Les 467 patients atteints de FA ayant subi une ICP de décembre 2015 à juillet 2018 qui ont fait l'objet de notre étude ont été trouvés lors de la vérification des dossiers par 47 cardiologues canadiens de l'étude CONNECT AF+PCI ( Co ordinated N ational N etwork to E ngage Interventional C ardiologists in the Antithrombotic T reatment of Patients With A trial F ibrillation Undergoing P ercutaneous C oronary I ntervention) pour déterminer les schémas de sélection du traitement antithrombotique initial. RÉSULTATS: Le score CHADS2 médian (25e, 75e percentile) était de 2 (1, 3), et l'ICP avait été réalisée dans le cadre du syndrome coronarien aigu chez 62,1 % des patients. La trithérapie antithrombotique (TTA) était le traitement initial chez 62,7 % des patients, la bithérapie, chez 25,7 % des patients, et la bithérapie antiplaquettaire, chez 11,6 % des patients, mais il y avait une augmentation temporelle dans l'utilisation de la bithérapie durant l'étude; la durée médiane prévue de la TTA était de 1 (1, 3) mois. Comparativement aux patients sélectionnés pour la TTA, les patients sélectionnés pour la bithérapie étaient moins susceptibles d'avoir eu un infarctus du myocarde précédent (35,8 % vs 25,8 %, P = 0,045) et une ICP précédente (33,8 % vs 23,3 %, P = 0,03), et recevaient des endoprothèses de longueur totale plus courte (38 [23, 56] vs 30 [20, 46] mm, P = 0,03). Les patients sélectionnés pour la bithérapie montraient une prévalence plus élevée d'accidents vasculaires cérébraux/accidents ischémiques transitoires (13,0 % vs 23,3 %, P = 0,01). Il n'existait aucune différence dans la prévalence de l'anémie (21,5 % vs 25,8 %, P = 0,30). L'utilisation de la bithérapie était similaire chez les patients atteints d'un syndrome coronarien aigu et chez les patients dont la maladie était stable (24,1 % vs 28,2 %, P = 0,32). CONCLUSIONS: Dans la pratique canadienne, environ le quart des patients atteints de FA qui subissent une ICP sont traités par bithérapie, mais durant la période étudiée, son utilisation avait augmenté. Les patients sélectionnés pour la bithérapie ont des antécédents et des interventions liées aux maladies coronariennes moins complexes.

Head-to-Head Comparison of Consensus-Recommended Platelet Function Tests to Assess P2Y12 Inhibition-Insights for Multi-Center Trials.

The vasodilator-associated stimulated phosphoprotein (VASP) phosphorylation level is a highly specific method to assess P2Y12 receptor inhibition. Traditionally, VASP phosphorylation is analyzed by flow cytometry, which is laborious and restricted to specialized laboratories. Recently, a simple ELISA kit has been commercialized. The primary objective of this study was to compare the performance of VASP assessment by ELISA and flow cytometry in relation to functional platelet aggregation testing by Multiplate® whole-blood aggregometry. Blood from 24 healthy volunteers was incubated with increasing concentration of a P2Y12 receptor inhibitor (AR-C 66096). Platelet function testing was carried out simultaneously by Multiplate® aggregometry and by VASP assessment through ELISA and flow cytometry. As expected, increasing concentrations of the P2Y12 receptor inhibitor induced a proportional inhibition of platelet aggregation and P2Y12 receptor activation across the modalities. Platelet reactivity index values of both ELISA- and flow cytometry-based VASP assessment methods correlated strongly (r = 0.87, p < 0.0001) and showed minimal bias (1.05%). Correlation with Multiplate® was slightly higher for the flow cytometry-based VASP assay (r = 0.79, p < 0.0001) than for the ELISA-based assay (r = 0.69, p < 0.0001). Intraclass correlation (ICC) was moderate for all the assays tested (ICC between 0.62 and 0.84). However, categorization into low, optimal, or high platelet reactivity based on these assays was strongly concordant (κ between 0.86 and 0.92). In conclusion, the consensus-recommended assays with their standardized cut-offs should not be used interchangeably in multi-center clinical studies but, rather, they should be standardized throughout sites.

Delays in ST-Elevation Myocardial Infarction Care During the COVID-19 Lockdown: An Observational Study.

BACKGROUND: Management of ST-elevated myocardial infarction (STEMI) necessitates rapid reperfusion. Delays prolong myocardial ischemia and increase the risk of complications, including death. The COVID-19 pandemic may have impacted STEMI management. We evaluated the relative volume of hospitalizations and clinical time intervals within a regional STEMI system. METHODS: 494 patients with STEMI were grouped into pre-lockdown, lockdown and re-opening cohorts. Clinical, temporal and outcome data were collected and compared between groups for both urban and rural patients, receiving primary percutaneous coronary intervention (PCI) and pharmacoinvasive revascularization, respectively. Data was compared to a 10-year historical comparator. RESULTS: During pre-lockdown there was 238 cases versus 193 in lockdown; a 19.0% reduction in volume. When lockdown was compared to the median caseload from a 10-year historical cohort, a 19.8% reduction was observed. For patients treated with primary PCI during lockdown, median symptom-to-balloon time increased by 44-minutes [217 (IQR 157-387) vs. 261 (160-659) minutes; p=0.03]; driven by an increase in median symptom-to-door time of 41-minutes [136 (IQR 80-267) vs. 177 (IQR 90-569) minutes; p<0.01]. Only patients transferred from non-PCI facilities demonstrated an increase in door-to-reperfusion time [116 (IQR 93-150) vs. 139 (IQR 100-199) minutes; p<0.01]. More patients had left ventricular dysfunction during the lockdown [35% vs. 44%; p=0.04], but there was no difference in mortality. CONCLUSION: During the COVID-19 lockdown, fewer patients presented with STEMI. Time-to-reperfusion was significantly prolonged and appeared driven predominantly by patient-level and transfer delays. Public education and systems-level changes will be integral to STEMI care during the second wave of COVID-19.

Dual antiplatelet therapy following percutaneous coronary intervention: protocol for a systematic review.

INTRODUCTION: Dual antiplatelet therapy (DAPT) is routinely given to patients after percutaneous coronary intervention (PCI) with stenting; however, there is ongoing debate about the optimal duration, especially in specific patient groups. In the proposed systematic review, we intend to assess the optimal duration of DAPT following PCI with stenting, with a focus on clinically relevant patient subgroups. METHODS AND ANALYSIS: We will perform a comprehensive search of the published literature for randomised controlled trials (RCTs) assessing the benefits and harms of extended DAPT (>12 months) compared with short-term DAPT (6-12 months) following PCI with stenting (bare metal or drug eluting). ClinicalTrials.gov and ICTRP will also be searched to identify ongoing and completed clinical trials. Two independent reviewers will select studies for inclusion, and the risk of bias will be assessed by use of Cochrane's Risk of Bias tool. The primary outcome of interest is death (all-cause, cardiovascular, non-cardiovascular). Secondary outcomes are bleeding (major, minor, gastrointestinal), urgent target vessel revascularisation, major adverse cardiovascular events, myocardial infarction, stroke and stent thrombosis. Subgroup data will be sought for patients with prior myocardial infarction, acute coronary syndrome at presentation and diabetes, and based on smoking status and age group. Data will be analysed by random-effects meta-analysis, and separate analyses will be performed for patient subgroups. Bayesian network meta-analysis will be performed to investigate the effect of individual P2Y12 inhibitors at different DAPT durations longer than 6 months. ETHICS AND DISSEMINATION: This review will provide a comprehensive overview of the available evidence of the benefits and harms associated with extending DAPT beyond 12 months following PCI with stenting and the effects on clinically important subgroups. The results of this review will inform clinical and policy decisions regarding the optimal treatment duration of DAPT following PCI with stenting. SYSTEMATIC REVIEW REGISTRATION: PROSPERO no. CRD42018082587.

Optimal Duration of Dual Antiplatelet Therapy Following Percutaneous Coronary Intervention: An Umbrella Review.

BACKGROUND: The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention with stenting requires consideration of patient characteristics, and decision makers require a comprehensive overview of the evidence. METHODS: We performed an umbrella review of systematic reviews (SRs) of randomized controlled trials of extended DAPT (> 12 months) compared with DAPT for 6 to 12 months after percutaneous coronary intervention with stenting. Outcomes of interest were death, myocardial infarction (MI), stroke, stent thrombosis, major adverse cardiac and cerebrovascular events, bleeding, and urgent revascularization. We aimed to assess the evidence of benefits and harms among clinically important subgroups (eg, elderly patients, those with diabetes, prior MI, acute coronary syndrome). We assessed the quality of the included reviews by use of A Measurement Tool to Assess Systematic Reviews (AMSTAR). RESULTS: Sixteen SRs involving 8 randomized controlled trials were included. Most scored 7 or more points on the AMSTAR checklist. There was no significant difference in outcomes with extended DAPT compared with 6 months of DAPT in most SRs, with the exception of an increased risk of major bleeding. Compared with 12 months, extended DAPT may reduce the risk of MI and stent thrombosis; however, the findings were not consistent across all reviews. There have been conflicting reports of an increased risk of death with extended DAPT. Few SRs assessed outcomes among patient subgroups. CONCLUSIONS: Extended DAPT may reduce the risk of MI and stent thrombosis but increase the risk of major bleeding and death. Whether the effects of extended DAPT are consistent across patient subgroups is unclear, and future SRs should address this knowledge gap.

Same-Day Discharge After Elective Percutaneous Coronary Interventions in Ontario, Canada.

Background To manage overcrowding and bed shortages in Canadian hospitals, same-day discharge (SDD) after percutaneous coronary intervention (PCI) has emerged as a solution to improve resource utilization. However, limited information exists regarding current trends, hospital variation, and safety of SDD PCI in Canada. Methods and Results We evaluated outpatients undergoing elective PCI in Ontario, Canada, from October 2008 to March 2016. SDD was defined when patients were discharged on the day of PCI, and non-SDD was defined as those patients who had 1 overnight stay. The primary outcome was 30-day all-cause death or hospitalization for acute coronary syndrome. Inverse probability of treatment weighting with propensity score was used to account for differences in baseline and clinical characteristics between SDD and non-SDD groups. Among 35 972 patients who underwent elective PCI at 17 PCI centers in Ontario, 10 801 patients (30%) had SDD PCI and 25 121 patients (70%) had non-SDD PCI. Substantial hospital variation for SDD PCI was observed, ranging from 0% to 87% during the study period. In the propensity-weighted cohort, SDD patients had no significant difference in 30-day rates of death or hospitalization for acute coronary syndrome (1.3% versus 1.6%; hazard ratio: 0.84 [95% CI, 0.65-1.08]; P=0.17) compared with non-SDD patients. SDD and non-SDD patients also had no significant difference in 30-day rates of mortality or coronary revascularization. Conclusions In this large population-based cohort of elective PCI patients, we demonstrated the safety of SDD PCI. Increased adoption of this strategy could lead to improved bed-flow efficiency and substantial savings for the Canadian healthcare system without comprising outcomes.

Clopidogrel Pharmacogenetics.

Common genetic variation in CYP2C19 (cytochrome P450, family 2, subfamily C, polypeptide 19) *2 and *3 alleles leads to a loss of functional protein, and carriers of these loss-of-function alleles when treated with clopidogrel have significantly reduced clopidogrel active metabolite levels and high on-treatment platelet reactivity resulting in increased risk of major adverse cardiovascular events, especially after percutaneous coronary intervention. The Food and Drug Administration has issued a black box warning advising practitioners to consider alternative treatment in CYP2C19 poor metabolizers who might receive clopidogrel and to identify such patients by genotyping. However, routine clinical use of genotyping for CYP2C19 loss-of-function alleles in patients undergoing percutaneous coronary intervention is not recommended by clinical guidelines because of lack of prospective evidence. To address this critical gap, TAILOR-PCI (Tailored Antiplatelet Initiation to Lessen Outcomes due to Decreased Clopidogrel Response After Percutaneous Coronary Intervention) is a large, pragmatic, randomized trial comparing point-of-care genotype-guided antiplatelet therapy with routine care to determine whether identifying CYP2C19 loss-of-function allele patients prospectively and prescribing alternative antiplatelet therapy is beneficial.

Updated Expert Consensus Statement on Platelet Function and Genetic Testing for Guiding P2Y12 Receptor Inhibitor Treatment in Percutaneous Coronary Intervention.

Dual-antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor is the standard treatment for patients undergoing percutaneous coronary intervention. The availability of different P2Y12 receptor inhibitors (clopidogrel, prasugrel, ticagrelor) with varying levels of potency has enabled physicians to contemplate individualized treatment regimens, which may include escalation or de-escalation of P2Y12-inhibiting therapy. Indeed, individualized and alternative DAPT strategies may be chosen according to the clinical setting (stable coronary artery disease vs. acute coronary syndrome), the stage of the disease (early- vs. long-term treatment), and patient risk for ischemic and bleeding complications. A tailored DAPT approach may be potentially guided by platelet function testing (PFT) or genetic testing. Although the routine use of PFT or genetic testing in percutaneous coronary intervention-treated patients is not recommended, recent data have led to an update in guideline recommendations that allow considering selective use of PFT for DAPT de-escalation. However, guidelines do not expand on when to implement the selective use of such assays into decision making for personalized treatment approaches. Therefore, an international expert consensus group of key leaders from North America, Asia, and Europe with expertise in the field of antiplatelet treatment was convened. This document updates 2 prior consensus papers on this topic and summarizes the contemporary updated expert consensus recommendations for the selective use of PFT or genotyping in patients undergoing percutaneous coronary intervention.