Antithrombotic therapies in Canadian atrial fibrillation patients with concomitant coronary artery disease: Insights from the CONNECT AF + PCI-II program.

BACKGROUND: Selecting the appropriate antithrombotic regimen for patients with atrial fibrillation (AF) who have undergone percutaneous coronary intervention (PCI) or have had medically managed acute coronary syndrome (ACS) remains complex. This multi-centre observational study evaluated patterns of antithrombotic therapies utilized among Canadian patients with AF post-PCI or ACS. METHODS AND RESULTS: By retrospective chart audit, 611 non-valvular AF patients [median (interquartile range) age 76 (69-83) years, CHADS2 score 2 (1-3)] who underwent PCI or had medically managed ACS between August 2018 and December 2020 were identified by 68 cardiologists across eight provinces in Canada. Overall, triple antithrombotic therapy [TAT: combined oral anticoagulation (OAC) and dual antiplatelet therapy (DAPT)] was the most common initial antithrombotic strategy, with use in 53.8 % of patients, followed by dual pathway therapy (32.7 % received OAC and a P2Y12 inhibitor, and 4.1 % received OAC and aspirin) and DAPT (9.3 %). Median duration of TAT was 30 (7, 30) days. Compared to the previous CONNECT AF + PCI-I program, there was an increased use of dual pathway therapy relative to TAT over time (P-value <.0001). DOACs (direct oral anticoagulants) represented 90.3 % of all OACs used overall, with apixaban being the most utilized (50.5 %). Proton pump inhibitors were used in 57.0 % of all patients, and 70.1 % of patients on ASA. Planned antithrombotic therapies at 1 year were: 76.2 % OAC monotherapy, 8.3 % OAC + ASA, 7.9 % OAC + P2Y12 inhibitor, 4.3 % DAPT, 1.3 % ASA alone, and <1 % triple therapy. CONCLUSION: In accordance with recent Canadian Cardiovascular Society guideline recommendations, we observed an increased use of dual pathway therapy relative to TAT over time in both AF patients post-PCI (elective and emergent) and in those with medically managed ACS. Additionally, DOACs have become the prevailing form of anticoagulation across all antithrombotic regimens. Our findings suggest that Canadian physicians are integrating evidence-based approaches to optimally manage the bleeding and thrombotic risks of AF patients post-PCI and/or ACS.

Use and outcomes of dual antiplatelet therapy for acute coronary syndrome in patients with chronic kidney disease: insights from the Canadian Observational Antiplatelet Study (COAPT).

Chronic kidney disease (CKD) increases the risk of adverse outcomes in acute coronary syndrome (ACS). The optimal regimen of dual antiplatelet therapy (DAPT) post-percutaneous coronary intervention (PCI) in CKD poses a challenge due to the increased bleeding and clotting tendencies, particularly since patients with CKD were underrepresented in randomized controlled trials. We examined the practice patterns of DAPT prescription stratified by the presence of CKD. The multicentre prospective Canadian Observational Antiplatelet Study (COAPT) enrolled patients with ACS between December 2011 and May 2013. The present study is a subgroup analysis comparing type and duration of DAPT and associated outcomes among patients with and without CKD (eGFR < 60 ml/min/1.73 m2, calculated by CKD-EPI). Patients with CKD (275/1921, 14.3%) were prescribed prasugrel/ticagrelor less (18.5% vs 25.8%, p = 0.01) and had a shorter duration of DAPT therapy versus patients without CKD (median 382 vs 402 days, p = 0.003). CKD was associated with major adverse cardiovascular events (MACE) at 12 months (p < 0.001) but not bleeding when compared to patients without CKD. CKD was associated with MACE in both patients on prasugrel/ticagrelor (p = 0.017) and those on clopidogrel (p < 0.001) (p for heterogeneity = 0.70). CKD was associated with increased bleeding only among patients receiving prasugrel/ticagrelor (p = 0.007), but not among those receiving clopidogrel (p = 0.64) (p for heterogeneity = 0.036). Patients with CKD had a shorter DAPT duration and were less frequently prescribed potent P2Y12 inhibitors than patients without CKD. Overall, compared with patients without CKD, patients with CKD had higher rates of MACE and similar bleeding rates. However, among those prescribed more potent P2Y12 inhibitors, CKD was associated with more bleeding than those without CKD. Further studies are needed to better define the benefit/risk evaluation, and establish a more tailored and evidence-based DAPT regimen for this high-risk patient group.

Use of antithrombotic therapy for secondary prevention in patients with stable atherosclerotic cardiovascular disease: Insights from the COordinated National Network to Engage Cardiologists in the antithrombotic Treatment of patients with CardioVascular Disease (CONNECT-CVD) study.

BACKGROUND: Although acetylsalicylic acid is the most commonly used antithrombotic agent for the secondary prevention of cardiovascular events, residual atherothrombotic risk has prompted a guideline recommendation for the addition of dual antiplatelet therapy (DAPT) or dual pathway inhibition (DPI) in high vascular risk patients. Accordingly, the CONNECT CVD quality enhancement initiative provides a contemporary "snapshot" of the clinical features and antithrombotic management of atherosclerotic cardiovascular disease (ASCVD) patients in Canada. METHODS: Canadian cardiologists (49 cardiologists from six provinces) undertook a retrospective chart audit of 10 ASCVD patients in their outpatient practice who met the Cardiovascular Outcomes for People Using Anticoagulation Strategy-like criteria from May 2018 to April 2019. RESULTS: Of the 492 (two cardiologists provided 11 patients) enroled, average age was 70 years, 25% were female, 39% had diabetes and 20% had atrial fibrillation. Prior revascularisation was common (percutaneous coronary artery intervention 61%, coronary artery bypass graft 39%), with 31% having multivessel disease. A total of 47% of patients had a Reduction of Atherothrombosis for Continued Health bleeding score of ≥11 (~2.8% risk of serious bleeding at 2 years). Single antiplatelet therapy (SAPT) alone was most commonly used (62%), while 22% were on DAPT alone. In total, 22% were on oral anticoagulation (OAC), with 16% being on non-vitamin K oral anticoagulant alone, 5% on DPI and 1% received triple therapy. CONCLUSIONS: In contemporary Canadian clinical practice of stable ASCVD patients, a large number of patients receive antithrombotic therapy other than SAPT. Further efforts are required to guide the appropriate selection of patients in whom more potent antithrombotic therapies may safely reduce residual risk.

Contemporary use of guideline-based higher potency P2Y12 receptor inhibitor therapy in patients with moderate-to-high risk non-ST-segment elevation myocardial infarction: Results from the Canadian ACS reflective II cross-sectional study.

BACKGROUND: After myocardial infarction, guidelines recommend higher-potency P2Y12 receptor inhibitors, namely ticagrelor and prasugrel, over clopidogrel. HYPOTHESIS: We aimed to determine the contemporary use of higher-potency antiplatelet therapy in Canadian patients with non-ST-elevation myocardial infarction (NSTEMI). METHODS: A total of 684 moderate-to-high risk NSTEMI patients were enrolled in the prospective Canadian ACS Reflective II registry at 12 Canadian hospitals and three clinics in five provinces between July 2016 and May 2018. Multivariable logistic regression modeling was performed to assess factors independently associated with higher-potency P2Y12 receptor inhibitor use at discharge. RESULTS: At hospital discharge, 78.3% of patients were treated with a P2Y12 receptor inhibitor. Among patients discharged on a P2Y12 receptor inhibitor, use of higher-potency P2Y12 receptor inhibitor was 61.4%. After adjustment, treatment in-hospital with PCI (OR 4.48, 95%CI 3.34-6.03, p < .0001) was most strongly associated with higher use of higher-potency P2Y12 receptor inhibitor, while oral anticoagulant use at discharge (OR 0.03, 95%CI 0.01-0.12, p < .0001), and atrial fibrillation (OR 0.40, 95%CI 0.17-0.98, p = .046) were most strongly associated with lower use of higher-potency P2Y12 receptor inhibitor. Use of higher-potency P2Y12 receptor inhibitor varied across provinces (range, 21.6%-78.9%). DISCUSSION: In contemporary Canadian practice, approximately 60% of moderate-to-high risk NSTEMI patients discharged on a P2Y12 receptor inhibitor are treated with a higher-potency P2Y12 receptor inhibitor. In addition to factors that increase risk of bleeding, interprovincial differences in practice patterns were associated with use of higher-potency P2Y12 receptor inhibitor at discharge. Opportunities remain for further optimization of evidence-based, guideline-recommended antiplatelet therapy use.

Racial Disparities in Acute Coronary Syndrome Management Within a Universal Healthcare Context: Insights From the AMI-OPTIMA Trial.

BACKGROUND: Although prior studies have demonstrated racial disparities regarding acute coronary syndrome (ACS) care within private or mixed healthcare systems, few researchers have explored such disparities within universal healthcare systems. We aimed to evaluate the quality and outcomes of in-hospital ACS management for White patients vs patients of colour, within a universal healthcare context. METHODS: We performed a post hoc analysis of the Acute Myocardial Infarction - Knowledge Translation to Optimize Adherence to Evidence-Based Therapy study, a cluster-randomized trial evaluating a knowledge-translation intervention at 24 hospitals in Quebec, Canada (years: 2009 and 2012). The primary endpoint was coronary catheterization. The secondary endpoints included in-hospital mortality, percutaneous and surgical coronary revascularization, major bleeding, total stroke, and discharge prescription of evidence-based medical therapy. RESULTS: Of 3444 included patients, 2738 were White, and 706 were people of colour. The mean age was 68.2 years (33.3% women) among White patients and 69.5 years (36.0% women) among patients of colour. Patients of colour were less likely to undergo in-hospital coronary catheterization than were White patients (74.5% vs 80.3%, P = 0.001). This difference was attenuated after adjusting for patient-level characteristics (odds ratio 0.89; 95% confidence interval 0.73-1.09), and it was eliminated after adjusting for hospital-level characteristics (odds ratio 1.04; 95% confidence interval 0.73-1.49). CONCLUSIONS: Racial disparity in coronary catheterization for ACS persists within a universal healthcare context. Patients' comorbidities and hospital-level factors may be partially responsible for this inequality. Future research on cardiovascular healthcare in patients with diverse racial/ethnic backgrounds in universal healthcare systems is needed to remediate racial inequality in ACS management.

CONTEXTE: Bien que des études antérieures aient démontré l'existence de disparités raciales dans la prise en charge du syndrome coronarien aigu (SCA) au sein de systèmes de santé privés ou mixtes, peu de chercheurs ont étudié ces disparités au sein de systèmes universels de soins de santé. Nous avons cherché à évaluer la qualité et les résultats de la prise en charge du SCA à l'hôpital pour les patients blancs par rapport aux patients de couleur, dans un contexte de soins de santé universels. MÉTHODOLOGIE: Nous avons effectué une analyse a posteriori de l'étude AMI-OPTIMA, un essai sur échantillon en grappes aléatoire évaluant une intervention d'application des connaissances dans 24 hôpitaux du Québec, au Canada (années : 2009 et 2012). Le paramètre d'évaluation principal était le cathétérisme coronaire. Les paramètres d'évaluation secondaires comprenaient la mortalité à l'hôpital, la revascularisation coronaire percutanée et chirurgicale, l'hémorragie majeure, l'accident vasculaire cérébral et la prescription au congé d'un traitement médical fondé sur des données probantes. RÉSULTATS: Sur les 3444 patients étudiés, 2738 étaient blancs et 706 étaient des personnes de couleur. L'âge moyen était de 68,2 ans (33,3 % de femmes) chez les patients blancs, et de 69,5 ans (36,0 % de femmes) chez les patients de couleur. Les patients de couleur étaient moins susceptibles de subir un cathétérisme coronaire à l'hôpital que les patients blancs (74,5 % contre 80,3 %, p = 0,001). Cette différence a été atténuée après ajustement pour tenir compte des caractéristiques des patients (rapport de cotes : 0,89; intervalle de confiance [IC] à 95 % : 0,73-1,09), et éliminée après ajustement pour tenir compte des caractéristiques des hôpitaux (rapport de cotes : 1,04; IC à 95 % : 0,73-1,49). CONCLUSIONS: La disparité raciale en ce qui a trait au cathétérisme coronaire pour un SCA persiste dans un contexte de soins de santé universels. Les comorbidités des patients et des facteurs liés à l'hôpital peuvent être partiellement responsables de cette inégalité. De plus amples recherches sur les soins cardiovasculaires chez les patients de diverses origines raciales ou ethniques dans les systèmes universels de soins de santé sont nécessaires pour remédier aux inégalités raciales dans la prise en charge du SCA.

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.

Provision of a DAPT Score to Cardiologists and Extension of Dual Antiplatelet Therapy Beyond 1 Year After ACS: Randomized Substudy of the Prospective Canadian ACS Reflective II Study.

BACKGROUND: Extension of dual antiplatelet therapy (DAPT) beyond 1 year after acute coronary syndrome is associated with a reduction in ischemic events but also increased bleeding. The DAPT score identifies individuals likely to derive overall benefit or harm from DAPT extension. We sought to evaluate the impact of providing the DAPT score to treating physicians on the decision to extend DAPT beyond 1 year after non-ST-segment elevation myocardial infarction. METHODS: Moderate to high-risk non-ST-segment elevation myocardial infarction patients were enrolled from July 2016 to May 2018 in 13 Canadian hospitals by 52 cardiologists. Participating cardiologists were randomly assigned 1:1 to receive their individual patients' DAPT scores before the 1-year follow-up visit vs not receiving their patients' DAPT scores. Rates of DAPT extension were compared among the randomized groups. RESULTS: At 1 year, 370 of the 585 (63.2%) patients discharged on DAPT were receiving DAPT. Among patients on DAPT at 1 year, the median (25th, 75th percentile) DAPT score was 2 (1,3). DAPT was extended beyond 1 year in 36.2% randomly assigned to provision of DAPT score vs 35.7% in the control group (P = 0.93). In the subgroup of patients with DAPT score ≥ 2, DAPT extension was 49.5% in the DAPT score provision arm vs 40.4% in the control arm (P = 0.22); among patients with DAPT score < 2, DAPT termination was 78.6% in the DAPT score provision arm vs 70.6% in the control arm (P = 0.26) (P value for interaction = 0.1). CONCLUSIONS: In this exploratory randomized trial, provision of the DAPT score to treating physicians had no impact on the duration of DAPT treatment beyond 1 year.

INTRODUCTION: La prolongation de la bithérapie antiplaquettaire au-delà d'un an après un syndrome coronarien aigu est associée à la réduction des accidents ischémiques, mais aussi à l'augmentation des hémorragies. Le score de bithérapie antiplaquettaire permet de déterminer les individus susceptibles d'obtenir des avantages globaux ou des inconvénients de la prolongation de la bithérapie antiplaquettaire. Nous avons cherché à évaluer les répercussions de l'obtention du score de bithérapie antiplaquettaire par les médecins traitants sur la décision quant à la prolongation de la bithérapie antiplaquettaire au-delà d'un an après l'infarctus du myocarde sans élévation du segment ST. MÉTHODES: De juillet 2016 à mai 2018, 52 cardiologues de 13 hôpitaux du Canada ont inscrit des patients exposés à un risque modéré à élevé d'infarctus du myocarde sans élévation du segment ST. Nous avons réparti de façon aléatoire selon un rapport 1:1 les cardiologues participants qui recevaient les scores de bithérapie antiplaquettaire individuels de leurs patients avant la consultation de suivi après un an vs ceux qui ne recevaient pas les scores de bithérapie antiplaquettaire de leurs patients. Nous avons comparé les taux de prolongation de la bithérapie antiplaquettaire des groupes répartis de façon aléatoire. RÉSULTATS: Après un an, 370 (63,2 %) patients sur 585 qui avaient eu à la sortie de l'hôpital une bithérapie antiplaquettaire recevaient la bithérapie antiplaquettaire. Parmi les patients qui prenaient la bithérapie antiplaquettaire après un an, le score médian de bithérapie antiplaquettaire (25e, 75e percentiles) était de 2 (1, 3). La bithérapie antiplaquettaire était prolongée au-delà d'un an chez 36,2 % des patients répartis de façon aléatoire qui avaient un score de bithérapie antiplaquettaire vs 35,7 % dans le groupe témoin (P = 0,93). Dans le sous-groupe de patients qui avaient un score de bithérapie antiplaquettaire ≥ 2, la prolongation de la bithérapie antiplaquettaire était de 49,5 % dans le bras qui avait un score de bithérapie antiplaquettaire vs 40,4 % dans le bras témoin (P = 0,22); parmi les patients qui avaient un score de bithérapie antiplaquettaire < 2, la cessation de la bithérapie antiplaquettaire était de 78,6 % dans le bras qui avait un score de bithérapie antiplaquettaire vs 70,6 % dans le bras témoin (P = 0,26) (valeur P pour l'interaction = 0,1). CONCLUSIONS: Dans cet essai exploratoire à répartition aléatoire, l'obtention du score de la bithérapie antiplaquettaire par les médecins traitants n'a pas engendré de répercussions sur la durée de la bithérapie antiplaquettaire au-delà d'un an.

Genomewide Association Study of Platelet Reactivity and Cardiovascular Response in Patients Treated With Clopidogrel: A Study by the International Clopidogrel Pharmacogenomics Consortium.

Antiplatelet response to clopidogrel shows wide variation, and poor response is correlated with adverse clinical outcomes. CYP2C19 loss-of-function alleles play an important role in this response, but account for only a small proportion of variability in response to clopidogrel. An aim of the International Clopidogrel Pharmacogenomics Consortium (ICPC) is to identify other genetic determinants of clopidogrel pharmacodynamics and clinical response. A genomewide association study (GWAS) was performed using DNA from 2,750 European ancestry individuals, using adenosine diphosphate-induced platelet reactivity and major cardiovascular and cerebrovascular events as outcome parameters. GWAS for platelet reactivity revealed a strong signal for CYP2C19*2 (P value = 1.67e-33). After correction for CYP2C19*2 no other single-nucleotide polymorphism reached genomewide significance. GWAS for a combined clinical end point of cardiovascular death, myocardial infarction, or stroke (5.0% event rate), or a combined end point of cardiovascular death or myocardial infarction (4.7% event rate) showed no significant results, although in coronary artery disease, percutaneous coronary intervention, and acute coronary syndrome subgroups, mutations in SCOS5P1, CDC42BPA, and CTRAC1 showed genomewide significance (lowest P values: 1.07e-09, 4.53e-08, and 2.60e-10, respectively). CYP2C19*2 is the strongest genetic determinant of on-clopidogrel platelet reactivity. We identified three novel associations in clinical outcome subgroups, suggestive for each of these outcomes.

Pharmacogenomic polygenic response score predicts ischaemic events and cardiovascular mortality in clopidogrel-treated patients.

AIMS: Clopidogrel is prescribed for the prevention of atherothrombotic events. While investigations have identified genetic determinants of inter-individual variability in on-treatment platelet inhibition (e.g. CYP2C19*2), evidence that these variants have clinical utility to predict major adverse cardiovascular events (CVEs) remains controversial. METHODS AND RESULTS: We assessed the impact of 31 candidate gene polymorphisms on adenosine diphosphate (ADP)-stimulated platelet reactivity in 3391 clopidogrel-treated coronary artery disease patients of the International Clopidogrel Pharmacogenomics Consortium (ICPC). The influence of these polymorphisms on CVEs was tested in 2134 ICPC patients (N = 129 events) in whom clinical event data were available. Several variants were associated with on-treatment ADP-stimulated platelet reactivity (CYP2C19*2, P = 8.8 × 10-54; CES1 G143E, P = 1.3 × 10-16; CYP2C19*17, P = 9.5 × 10-10; CYP2B6 1294 + 53 C > T, P = 3.0 × 10-4; CYP2B6 516 G > T, P = 1.0 × 10-3; CYP2C9*2, P = 1.2 × 10-3; and CYP2C9*3, P = 1.5 × 10-3). While no individual variant was associated with CVEs, generation of a pharmacogenomic polygenic response score (PgxRS) revealed that patients who carried a greater number of alleles that associated with increased on-treatment platelet reactivity were more likely to experience CVEs (ß = 0.17, SE 0.06, P = 0.01) and cardiovascular-related death (ß = 0.43, SE 0.16, P = 0.007). Patients who carried eight or more risk alleles were significantly more likely to experience CVEs [odds ratio (OR) = 1.78, 95% confidence interval (CI) 1.14-2.76, P = 0.01] and cardiovascular death (OR = 4.39, 95% CI 1.35-14.27, P = 0.01) compared to patients who carried six or fewer of these alleles. CONCLUSION: Several polymorphisms impact clopidogrel response and PgxRS is a predictor of cardiovascular outcomes. Additional investigations that identify novel determinants of clopidogrel response and validating polygenic models may facilitate future precision medicine strategies.

Impact of an invasive strategy in the elderly hospitalized with acute coronary syndrome with emphasis on the nonagenarians.

BACKGROUND: Published data about nonagenarians with acute coronary syndrome (ACS) were mainly descriptive and limited by small sample sizes and unadjusted outcomes. We aim to describe the characteristics, management, and the impact of an invasive strategy on major adverse events in elderly patients hospitalized with ACS with focus on the nonagerians. METHODS AND RESULTS: We analyzed data collected as part of the AMI-OPTIMA study, a cluster-randomized study of knowledge translation intervention versus usual care on optimal discharge medications in patients admitted with ACS at 24 Canadian hospitals. To determine whether an invasive strategy improved outcomes in the elderly, we used inverse probability weighting to adjust for confounders between patients who underwent invasive versus conservative strategies. Of 4,569 consecutive patients: 2,395 (52%) were <70 years old, 1,031 (23%) were septuagenarians, 941 (21%) were octogenarians, and 202 (4.4%) were nonagenarians. An invasive strategy was associated with reduced in-hospital all-cause mortality in all age groups: 1.1% versus 3.8% in patients <70 years old (P < 0.001), 2.9% versus 7.4% in septuagenarians (P < 0.001), 5.1% versus 14.7% in octogenarians (P < 0.001), and 12.0% versus 25.1% in nonagenarians (P = 0.001). An invasive strategy was also associated with higher thrombolysis in myocardial infarction major bleeds in the nonagenarians (9.0% vs. 2.0%; P = 0.003). CONCLUSIONS: The reduction in in-hospital mortality associated with an invasive strategy in elderly and nonagenarians presented with ACS is generating hypothesis and merits further studies to confirm these benefits and to guide clinicians in the management of these high-risk patients.

Percutaneous coronary intervention for treating de-novo lesions in small coronary vessels: initial experience with the Essential paclitaxel-coated balloon.

BACKGROUND: Paclitaxel-coated balloon (PCB) coronary angioplasty is an alternative treatment for de-novo coronary lesions in small vessels. This study with the new Essential PCB aimed to evaluate early and mid-term clinical outcomes following angioplasty with the Essential PCB in the treatment of de-novo lesions in small vessels. PATIENTS AND METHODS: We included all patients who underwent PCB angioplasty for treating de-novo coronary lesions in small vessels (reference diameter <2.5 mm) between October 2015 and June 2016 in 2 centres. The primary endpoint was the 12-month target lesion failure (TLF) rate: a composite of cardiac death, target vessel-related myocardial infarction, and target lesion revascularization. The secondary endpoints were rates of target vessel failure and global major adverse cardiac events (MACE). RESULTS: A total of 71 patients (comprising 71 lesions) were included, with a mean age of 66±11 years. A 56% were diabetic and 70% had an acute coronary syndrome as an indication for coronary revascularization. The mean vessel diameter and lesion length were 2.21±0.41 and 20.7±9.2 mm, respectively. Predilatation was performed in 85.9% of patients. The median diameter, length, and inflation pressure of the Essential balloon were 2.0 [interquartile range (IQR): 2.0-2.5] mm, 20 (IQR: 15-30) mm, and 12±2 atmospheres, respectively. Angiographic success was achieved in 97.2% of cases, and bail-out stenting was required in nine (12.7%) cases. The incidence of TLF at the 12-month follow-up was 4.2%, with a target lesion revascularization rate of 4.2%. Target vessel failure and global MACE rates were 4.2 and 9.9%, respectively. CONCLUSION: Use of the Essential PCB for treating de-novo coronary lesions in small vessels was safe, with low TLF and MACE rates at the 12-month follow-up.

Genome-wide and candidate gene approaches of clopidogrel efficacy using pharmacodynamic and clinical end points-Rationale and design of the International Clopidogrel Pharmacogenomics Consortium (ICPC).

RATIONALE: The P2Y12 receptor inhibitor clopidogrel is widely used in patients with acute coronary syndrome, percutaneous coronary intervention, or ischemic stroke. Platelet inhibition by clopidogrel shows wide interpatient variability, and high on-treatment platelet reactivity is a risk factor for atherothrombotic events, particularly in high-risk populations. CYP2C19 polymorphism plays an important role in this variability, but heritability estimates suggest that additional genetic variants remain unidentified. The aim of the International Clopidogrel Pharmacogenomics Consortium (ICPC) is to identify genetic determinants of clopidogrel pharmacodynamics and clinical response. STUDY DESIGN: Based on the data published on www.clinicaltrials.gov, clopidogrel intervention studies containing genetic and platelet function data were identified for participation. Lead investigators were invited to share DNA samples, platelet function test results, patient characteristics, and cardiovascular outcomes to perform candidate gene and genome-wide studies. RESULTS: In total, 17 study sites from 13 countries participate in the ICPC, contributing individual patient data from 8,829 patients. Available adenosine diphosphate-stimulated platelet function tests included vasodilator-stimulated phosphoprotein assay, light transmittance aggregometry, and the VerifyNow P2Y12 assay. A proof-of-principle analysis based on genotype data provided by each group showed a strong and consistent association between CYP2C19*2 and platelet reactivity (P value=5.1 × 10-40). CONCLUSION: The ICPC aims to identify new loci influencing clopidogrel efficacy by using state-of-the-art genetic approaches in a large cohort of clopidogrel-treated patients to better understand the genetic basis of on-treatment response variability.

A Randomized Double-Blind Placebo-Controlled Study Comparing Intracoronary Versus Intravenous Abciximab in Patients With ST-Elevation Myocardial Infarction Undergoing Transradial Rescue Percutaneous Coronary Intervention After Failed Thrombolysis.

The risk and benefit ratio of glycoprotein IIb/IIIa inhibitors with dual oral antiplatelet therapy after failed thrombolysis and rescue percutaneous coronary intervention (PCI) is unclear. Using a randomized placebo-controlled, double-blind design, we compared intravenous (IV) and intracoronary (IC) abciximab delivery in 74 patients referred for rescue transradial PCI. The primary angiographic end points were the final thrombolysis in myocardial infarction flow and myocardial blush grades. Secondary end points included acute and 6-month outcomes using angiographic parameters, platelet aggregation parameters, cardiac biomarkers, cardiac magnetic resonance measurements (CMR) and clinical end points. After rescue PCI, normal thrombolysis in myocardial infarction 3 flows were obtained in 70% in the IC group, 48% in the IV group, and 71% in the placebo group, respectively (p = 0.056). Final myocardial blush grades 2 and 3 were obtained in 43% and 39% in the IC group, 48% and 26% in the IV group, and 46% and 42% in the placebo group (p = 0.67), respectively. Acutely, peak release of cardiac biomarkers, necrosis size, myocardial perfusion and no-reflow as assessed by CMR, and clinical end points were similar between the groups and did not suggest a benefit for IC or IV abciximab compared with placebo. There was no increase in bleeding or access site-related complications with abciximab compared with placebo. Clinical, angiographic, and CMR outcomes at 6 months remained comparable between the groups. In patients with ST-elevation myocardial infarction presenting with failed thrombolysis undergoing transradial rescue PCI, IC or IV abciximab had no significant clinical impact.

Marital status and outcomes after myocardial infarction: Observations from the Canadian Observational Antiplatelet Study (COAPT).

While divorced or living alone, patients with stable cardiovascular disease are at increased risk for adverse cardiovascular events. The importance of marital status following a myocardial infarction (MI) is less clear. We hypothesized that marital status may affect cardiovascular outcomes following MI. We analyzed outcomes among patients with MI who underwent percutaneous coronary intervention from the Canadian Observational Antiplatelet Study (COAPT). Marital status was categorized into 3 groups: married/common-law patients living together; never married; and divorced, separated, or widowed patients. Patients were followed for 15 months and our primary outcome was the occurrence of a major adverse cardiovascular event (MACE), defined as a composite of mortality, repeat acute MI, stroke, or urgent coronary revascularization. Multivariable logistic regression models were performed, with married/common-law patients living together considered the reference group. Among 2100 patients included in analyses, 1519 (72.3%) were married/common-law patients living together, 358 (17.1%) were separated/divorced/widowed, and 223 (10.6%) patients were never married. Dual antiplatelet therapy use after 15 months was similar across groups (75.4%, 77.8%, and 73.6%, respectively). The risk of MACE after 15 months was similar among married patients living together (12.7%; referent) compared with patients who were never married (13.9%; adjusted odds ratio: 1.09, 95% confidence interval: 0.58-2.07, P = 0.79) and patients separated/divorced/widowed (14.3%; adjusted odds ratio: 0.71, 95% confidence interval: 0.40-1.25, P = 0.23). Similarly, the risk of individual endpoints, including mortality, was similar across the 3 groups. Among patients stabilized following an MI, we found no association between marital status and 15-month outcomes.

Recurrent Cardiovascular Events in Survivors of Myocardial Infarction With ST-Segment Elevation (from the AMI-QUEBEC Study).

The characteristics and predictors of long-term recurrent ischemic cardiovascular events (RICEs) after myocardial infarction with ST-segment elevation (STEMI) have not yet been clarified. We aimed to characterize the 10-year incidence, types, and predictors of RICE. We obtained 10-year follow-up of STEMI survivors at 17 Quebec hospitals in Canada (the AMI-QUEBEC Study) in 2003. There were 858 patients; mean age was 60 years and 73% were male. The majority of patients receive reperfusion therapy; 53.3% and 39.2% of patients received primary percutaneous coronary intervention (PCI) and fibrinolytic therapy, respectively. Seventy-five percent of patients underwent in-hospital PCI (elective, rescue, and primary). At 10 years, 42% of patients suffered a RICE, with most RICEs (88%) caused by recurrent cardiac ischemia. The risk of RICE was the highest during the first year (23.5 per patient-year). At 10 years, the all-cause mortality was 19.3%, with 1/3 of deaths being RICE-related. Previous cardiovascular event, heart failure during the index STEMI hospitalization, discharge prescription of calcium blocker increased the risk of RICE by almost twofold. Each point increase in TIMI (Thrombolysis In Myocardial Infarction) score augmented the risk of RICE by 6%, whereas discharge prescription of dual antiplatelets reduced the risk of RICE by 23%. Our findings suggested that survivors of STEMI remain at high long-term risk of RICE despite high rate of reperfusion therapy and in-hospital PCI. Patients with previous cardiovascular event, in-hospital heart failure, and high TIMI score were particularly susceptible to RICE. Future studies are needed to confirm the impacts of calcium blocker and dual antiplatelets on long-term risk of RICE.

Transradial experience with bioresorbable vascular scaffolds: A case-matched study with metallic drug-eluting stents.

BACKGROUND: Whether polymeric bioresorbable vascular scaffolds (BVS) implantation with transradial approach is feasible and safe is unknown. We compared the feasibility and safety of the transradial approach for BVS delivery with metallic drug-eluting stents (DES). METHODS: We identified 118 consecutive patients who underwent BVS implantation and we compared 30-days and 1-year results with 118 matched patients with DES. Patients were matched for age, sex, risk factors and clinical indication. RESULTS: Rates of transradial approach were 98% in the BVS group vs 95% in the DES group (P = 0.16) with 5Fr used in 38% and 32% (P = 0.34), respectively. The number of stents was similar in both groups, 2.6 ±â€¯1.5 vs 2.4 ±â€¯1.3 (P = 0.23). Although maximal pressure for stent deployment was identical in both groups (16 ±â€¯3 atm), more lesions were pre-dilated (83% vs 52%, P < 0.001) and post-dilated (71% vs 33%, P < 0.001) in the BVS group. Contrast volume (217 ±â€¯97 vs 175 ±â€¯108 ml, P < 0.001), fluoroscopy time (16 [10-23] vs 13 [8-21] min, P = 0.04) and procedure duration (65 ±â€¯31 vs 56 ±â€¯47 min, P = 0.045) were significantly higher in the BVS group. Major adverse cardiac events, including death, myocardial infarction and target vessel revascularization remained similar in both groups, 1.7% vs 0.8% (P = 0.56) at 30 days and 10% vs 8.5% (P = 0.66) at 1 year. At 1 year, stent thrombosis occurred in 2 (1.7%) patients in the BVS group and 1 (0.8%) patient in the DES group (P = 0.56). CONCLUSION: The use of transradial approach for BVS compared to DES implantation was feasible and safe in all-comers, although BVS implantation included more technical challenges. Outcomes up to 1-year remained comparable in both groups.

Ten-Year Statin Adherence in Survivors of ST-Segment Elevation Myocardial Infarction.

Background          Adherence to statins is often sub-optimal and declines over time. Direct costs incurred by patients are frequently cited as responsible for inadequate statin adherence. To determine whether survivors of ST-segment elevation myocardial infarction (STEMI), who benefit from low or no cost drug dispensation, have optimal long-term adherence to statins, we aimed to evaluate the ten-year adherence to statin of these patients. Methods          The AMI-QUEBEC Study follows a cohort of STEMI survivors hospitalized at 17 hospitals in Quebec, Canada during the year 2003. We obtained their 10-year data on lipid lowering therapy (LLT) consumption. Optimal adherence was defined as the proportion of days covered of ≥80%. We used multivariate logistic regression to determine factors independently associated with optimal adherence to statins. Results          Complete 10-year data on statin dispensation was available for 524 patients. Optimal adherence remained stable over time at 80% and more during the 10-year follow-up period. During the last five years, 12% of patients did not use any LLT. Older age, living in less socially deprived areas, concomitant use of angiotensin-converting-enzyme inhibitors (ACEI) or angiotensin receptor blockers (ARB), and admission to hospitals with percutaneous coronary interventions facilities (PCI-hospitals) were associated with improved statin adherence.   Conclusion Future studies are needed to explore the potential factors associated with concomitant use of ACEI/ARB, and admission to PCI-hospitals that may have optimized statin adherence. Socially deprived patients may benefit from more support and encouragement to enhance their long-term statin adherence.

Duration of dual antiplatelet therapy and associated outcomes following percutaneous coronary intervention for acute myocardial infarction: contemporary practice insights from the Canadian Observational Antiplatelet Study.

Aims: There is a paucity of real-world, contemporary data of practice patterns and clinical outcomes following dual-antiplatelet therapy (DAPT) in acute myocardial infarction (AMI) patients treated with percutaneous coronary intervention (PCI). Methods and results: The Canadian Observational Antiplatelet Study was a prospective, multicentre, cohort study examining adenosine diphosphate receptor antagonist use following PCI for AMI. We compared practice patterns, patient characteristics, and clinical outcomes in relation to DAPT duration (<6 weeks, 6 weeks to <6 months, 6 to <12, and ≥12 months). The primary outcome was the composite of non-fatal AMI, unplanned coronary revascularization, stent thrombosis, new or worsening heart failure, cardiogenic shock, or stroke. We identified 2034 patients with AMI treated with PCI. DAPT duration was <6 weeks in 5.2% of patients; 6 weeks to <6 months in 7.0%; 6 to <12 months in 12.6%; and ≥12 months in 75.3%. Patients who discontinued DAPT early had higher GRACE risk scores. Overall, mortality rate at 15 months was 2.5%. Compared with a duration of DAPT of ≥12 months, discontinuation of DAPT <6 weeks (P < 0.0001) and 6 weeks to <6 months (P = 0.02), but not 6 months to <12 months (P = 0.06), were independently associated with a higher incidence of the primary outcome among survivors. Conclusion: One-in-four patients with AMI treated with PCI discontinued DAPT prior to the guideline-recommended 12-month duration. Patients in whom DAPT was discontinued early were at higher baseline risk and had higher rates of non-fatal ischaemic events during follow up.

Feasibility and Safety of Early Repeat Transradial Access Within 30 Days of Previous Coronary Angiography and Intervention.

Transradial approach (TRA) is the default access site for diagnostic angiography and intervention in many centers. Repeat ipsilateral radial artery access late after index procedure has been associated with failures. It is unknown whether early (≤30 days) and very early (<24 hours) repeat radial access is technically feasible and safe. Study population consisted of consecutive patients undergoing repeat (≥2) procedures within 30 days in a high-volume TRA center. Transradial access failure and resulting femoral approach was categorized as primary (no repeat attempt) or secondary (crossover). Timing of repeat access and reasons for failure were recorded. From November 2012 to December 2014, repeat catheterization by TRA was performed twice in 573 of 626 patients (92%) (median delay 4 [2 to 9] days), 3 times in 29 of 38 (76%) patients (median delay 15 [5 to 26] days), and 4 times in 1 patient within 21 days. When repeat catheterization occurred during the first 24 hours following the index procedure, 53% and 75% of patients had second and third procedures using the same ipsilateral radial artery, respectively. Primary radial failure occurred in 5.8% for second attempt and 13% for a third attempt, whereas crossovers were noted in 2.7% and 2.6%, respectively. Main reasons for failed re-access of ipsilateral radial artery were related either to operator's reluctance to repeat attempt (primary failure) or to issues with puncture site (crossover). In a high-volume TRA center, patients who required repeat catheterization within 24 hours and within the first 30 days had the same radial artery re-accessed in the majority of cases.

Longitudinal treatment patterns with ADP receptor inhibitors after myocardial infarction: Insights from the Canadian Observational AntiPlatelet sTudy.

BACKGROUND: After myocardial infarction (MI) treated with percutaneous coronary intervention (PCI), guidelines recommend dual antiplatelet therapy (DAPT) with aspirin and an ADP receptor inhibitor (ADPri) for at least 1year. However, whether real-world Canadian practice patterns reflect this recommendation is unknown. METHODS: We studied 2175 MI patients treated with PCI and discharged from 26 Canadian hospitals between 12/2011 and 05/2013 in the Canadian Observational Antiplatelet sTudy (COAPT). Hierarchical Cox proportional hazard regression modeling was used to determine baseline demographic and clinical factors associated with duration of ADPri therapy post-discharge. RESULTS: At index-hospitalization discharge, 1597 (73%) patients were treated with clopidogrel, 220 (10%) with prasugrel, and 358 (17%) with ticagrelor. ADPri was discontinued prior to 1year in 474 (21.8%) patients; discontinuation rates were lowest for patients discharged on prasugrel (17.7%), compared with clopidogrel (22.5%) or ticagrelor (21.0%), (log rank test, p=0.03). In addition to regional variability, factors associated with shorter ADPri duration included older age, low body weight, Killip III/IV heart failure, atrial fibrillation, ticagrelor on discharge, and bare metal stent use, while longer ADPri duration was associated with history of prior MI. CONCLUSIONS: One in five PCI-treated MI patients did not complete Canadian guideline-recommended 1-year course of ADPri treatment. Premature ADPri discontinuation was most strongly associated with factors that increase the risk of bleeding. Further study is required to assess the clinical implications of premature ADPri discontinuation on patient outcomes.