Immature platelets and platelet reactivity in patients with acute ST-segment Elevation Myocardial Infarction using whole blood flow cytometry with SYTO-13 staining.

BACKGROUND: Reduced effect of antiplatelet therapy has been reported in patients with ST-segment elevation myocardial infarction (STEMI). Multiple factors may concur to explain this, including increased amount of highly reactive immature platelets. OBJECTIVES: To investigate the association between immature platelets and reactivity determined with multicolour flow cytometry using the SYTO-13 dye in STEMI patients. METHODS: We conducted an observational study of 59 patients with acute STEMI. Blood samples were obtained within 24 h after admission and after loading doses of dual antiplatelet therapy. For comparison, samples were obtained from 50 healthy individuals. Immature platelets and platelet reactivity were investigated using multicolour flow cytometry including the SYTO-13 dye that binds to platelet RNA and thus provides a method for subdividing platelets into immature and mature platelets. Additionally, we assessed platelet aggregation, serum-thromboxane B2 levels and standard immature platelet markers. RESULTS: Immature platelets were more reactive than mature platelets in both STEMI patients and healthy individuals (p-values < 0.05). STEMI patients had lower platelet aggregation and thromboxane B2 levels than healthy individuals. We found a positive association between automatically determined immature platelet markers and CD63 expression on activated platelets (Spearman's rho: 0.27 to 0.58, p-values < 0.05). CONCLUSIONS: Our study shows that immature platelets identified with a multicolour flow cytometric method using the SYTO-13 dye are more reactive than mature platelets in patients with acute STEMI and in healthy individuals. The presence of immature platelets may be important for the overall platelet reactivity, which may have implications for the effect of antiplatelet therapy.

Long-term outcomes after coronary intervention with biodegradable polymer stents in patients with acute coronary syndromes.

BACKGROUND: Patients with acute coronary syndromes (ACS) may have worse outcomes after percutaneous coronary intervention compared to patients without ACS. AIMS: To compare 5-year efficacy and safety outcomes in patients with and without ACS treated with biodegradable polymers, the ultrathin strut sirolimus-eluting Orsiro stent (O-SES) or the biolimus-eluting Nobori stent (N-BES). METHODS: The Scandinavian Organisation for Randomized Trials with Clinical Outcome VII is a randomized trial comparing O-SES and N-BES in an all-comer setting. Of 2525 patients, 1329 (53%) patients had ACS and 1196 (47%) patients were without ACS. Endpoints were target lesion failure (TLF) (a composite of cardiac death, target lesion myocardial infarction, or target lesion revascularization) and definite stent thrombosis within 5 years. RESULTS: At 5-year follow-up, TLF did not differ significantly between patients with and without ACS (12.3% vs. 13.2%; rate ratio (RR) 1.00; 95% confidence interval (CI): 0.70-1.44), whereas the risk of definite stent thrombosis was increased in patients with ACS (2.3% vs. 1.3; RR: 2.01 [95% CI: 1.01-3.98]). In patients with ACS, the rate of TLF was similar between O-SES and N-BES (12.4% vs. 12.3%; RR: 1.02; 95% CI: 0.74-1.40). The reduced risk of definite stent thrombosis in O-SES treated ACS patients within the first year (0.2% vs. 1.6%; RR: 0.12; 95% CI: 0.02-0.93) was not maintained after 5 years (1.8% vs. 2.7%; RR: 0.77; 95% CI: 0.37-1.63). CONCLUSION: Patients with ACS had an increased risk of stent thrombosis regardless of the stent type used. Long-term outcomes were similar for ACS patients treated with O-SES or N-BES at 5 years.

Platelet Function and Maturity and Related microRNA Expression in Whole Blood in Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Reduced effect of antiplatelet therapy has been reported in patients with ST-segment elevation myocardial infarction (STEMI). MicroRNAs (miRs) may influence platelet function and maturity, and subsequently the effect of antiplatelet therapy. OBJECTIVES: We aimed to explore the association between miR expression and platelet function and maturity in patients with acute STEMI and healthy individuals. METHODS: We performed an observational study of STEMI patients admitted directly to primary percutaneous coronary intervention. Patients were treated with antiplatelet therapy according to guidelines. Within 24 hours after admission, blood samples were obtained to measure: the expression of 10 candidate miRs, platelet function markers using advanced flow cytometry, platelet aggregation, serum thromboxane B2, and platelet maturity markers. Furthermore, blood samples from healthy individuals were obtained to determine the normal variation. RESULTS: In total, 61 STEMI patients and 50 healthy individuals were included. STEMI patients had higher expression of miR-21-5p, miR-26b-5p, and miR-223-3p and lower expression of miR-150-5p, miR423-5p, and miR-1180-3p than healthy individuals. In STEMI patients, the expression of miR-26b-5p showed the most consistent association with platelet function (all p-values <0.05, Spearman's rho ranging from 0.27 to 0.41), while the expression of miR-150-5p and miR-223-3p showed negative associations with platelet function. No association between miR expression and platelet maturity markers was observed. CONCLUSION: In patients with STEMI, the expression of six miRs was significantly different from healthy individuals. The expression of miR-26b-5p may affect platelet function in acute STEMI patients and potentially influence the effect of antiplatelet therapy.

Mortality Trends After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Observational studies have reported that mortality rates after ST-segment elevation myocardial infarction (STEMI) have been stable since 2006 to 2010. OBJECTIVES: The aim of this study was to evaluate the temporal trends in 1-year, 30-day, and 31- to 365-day mortality after STEMI in Western Denmark where primary percutaneous coronary intervention (PCI) has been the national reperfusion strategy since 2003. METHODS: Using the Western Denmark Heart Registry, the study identified first-time PCI-treated patients undergoing primary PCI (pPCI) for STEMI from 2003 to 2018. Based on the year of pPCI, patients were divided into 4 time-interval groups and followed up for 1 year using the Danish national health registries. RESULTS: A total of 19,613 patients were included. Median age was 64 years, and 74% were male. One-year mortality decreased gradually from 10.8% in 2003-2006, 10.4% in 2007-2010, 9.1% in 2011-2014, to 7.7% in 2015-2018 (2015-2018 vs 2003-2006: adjusted HR [aHR]: 0.71; 95% CI: 0.62-0.82). The largest absolute mortality decline occurred in the 0- to 30-day period with a 2.3% reduction (aHR: 0.69; 95% CI: 0.59-0.82), and to a lesser extent in the 31- to 365-day period (risk reduction: 1.0%; aHR: 0.71; 95% CI: 0.56-0.90). CONCLUSIONS: In a high-income European country with a fully implemented pPCI strategy, 1-year mortality in pPCI-treated patients with STEMI decreased substantially between 2003 and 2018. Approximately three-quarters of the absolute mortality reduction occurred within the first 30 days after pPCI. These results indicate that optimization of early management of pPCI-treated patients with STEMI offers great opportunities for improving overall survival in contemporary clinical practice.

Real-World Experience with Cangrelor as Adjuvant to Percutaneous Coronary Intervention: A Single-Centre Observational Study.

Background: Reversible P2Y12 inhibition can be obtained with cangrelor administered intravenously. More experience with cangrelor use in acute PCI with unknown bleeding risk is needed. Objectives: To describe real-world use of cangrelor including patient and procedure characteristics and patient outcomes. Methods: We performed a single-centre, retrospective, and observational study including all patients treated with cangrelor in relation to percutaneous coronary intervention at Aarhus University Hospital during the years 2016, 2017, and 2018. We recorded procedure indication and priority, the indications for cangrelor use, and patient outcomes within the first 48 hours after initiation of cangrelor treatment. Results: We treated 991 patients with cangrelor in the study period. Of these, 869 (87.7%) had an acute procedure priority. Among acute procedures, patients were mainly treated for STEMI (n = 723) and the remaining were treated for cardiac arrest and acute heart failure. Use of oral P2Y12 inhibitors prior to percutaneous coronary intervention was rare. Fatal bleeding events (n = 6) were only observed among patients undergoing acute procedures. Stent thrombosis was observed in two patients receiving acute treatment for STEMI. Thus, cangrelor can be used in relation to PCI under acute circumstances with advantages in terms of clinical management. The benefits and risks, in terms of patient outcomes, should ideally be assessed in randomized trials.

Myocardial perfusion imaging by 15O-H2O positron emission tomography predicts clinical revascularization procedures in symptomatic patients with previous coronary artery bypass graft.

Aims: We wanted to assess if 15O-H2O myocardial perfusion imaging (MPI) in a clinical setting can predict referral to coronary artery catheterization [coronary angiography (CAG)], execution of percutaneous coronary intervention (PCI), and post-PCI angina relief for patients with angina and previous coronary artery bypass graft (CABG). Methods and results: We analysed 172 symptomatic CABG patients referred for 15O-H2O positron emission tomography (PET) MPI at Aarhus University Hospital Department of Nuclear Medicine & PET Centre, of which five did not complete the scan. In total, 145 (87%) enrolled patients had an abnormal MPI. Of these, 86/145 (59%) underwent CAG within 3 months; however, no PET parameters predicted referral to CAG. During the CAG, 25/86 (29%) patients were revascularized by PCI. Relative flow reserve (RFR) (0.49 vs. 0.54 P = 0.03), vessel-specific myocardial blood flow (MBF) (1.53 vs. 1.88 mL/g/min, P < 0.01), and vessel-specific myocardial flow reserve (MFR) (1.73 vs. 2.13, P < 0.01) were significantly lower in patients revascularized by PCI. Receiver operating characteristic analysis of the vessel-specific parameters yielded optimal cutoffs of 1.36 mL/g/min (MBF) and 1.28 (MFR) to predict PCI. Angina relief was experienced by 18/24 (75%) of the patients who underwent PCI. Myocardial blood flow was an excellent predictor of angina relief on both a global [area under the curve (AUC) = 0.85, P < 0.01] and vessel-specific (AUC = 0.90, P < 0.01) level with optimal cutoff levels of 1.99 mL/g/min and 1.85 mL/g/min, respectively. Conclusion: For CABG patients, RFR, vessel-specific MBF, and vessel-specific MFR measured by 15O-H2O PET MPI predict whether subsequent CAG will result in PCI. Additionally, global and vessel-specific MBF values predict post-PCI angina relief.

Immature platelets and cardiovascular events in patients with stable coronary artery disease.

Many patients with coronary artery disease (CAD) have reduced the effect of aspirin, which may partly be explained by immature platelets. We aimed to investigate whether immature platelet markers can predict cardiovascular events in a large cohort of stable CAD patients. A total of 900 stable CAD patients were included and followed for a median of 3 years. We measured markers of immature platelets (platelet count, immature platelet count, immature platelet fraction, mean platelet volume, platelet distribution width, platelet mass, and thrombopoietin) using automated flow cytometry and studied their relation to cardiovascular events. Our primary endpoint was a composite of acute myocardial infarction (MI), ischemic stroke, and cardiovascular death. A composite of MI, ischemic stroke, stent thrombosis and all-cause mortality was analyzed as a secondary endpoint. We found no difference in immature platelet markers between CAD patients with or without cardiovascular events. Regression analysis using hazards rates showed that markers of immature platelets did not have any predictive value for endpoints (p-values >.05). Markers of immature platelets did not predict future cardiovascular events during a 3-year follow-up period in CAD patients. This suggests that immature platelets measured in a stable phase does not have a major role in predicting future cardiovascular events.

What is the context? Many patients with coronary artery disease (CAD) have reduced antiplatelet effect of aspirinThe reduced antiplatelet effect of aspirin is most likely multifactorial and may partly be explained by immature plateletsWhat is new? In a cohort of 900 stable CAD patients, we measured markers of immature platelets and studied their relation to cardiovascular events during a 3-year follow-upOur study demonstrated that markers of immature platelets did not predict cardiovascular events in our cohortWhat is the impact? The findings from the present study suggest that immature platelets, measured in a stable phase, do not have a major role in predicting future cardiovascular events in CAD patients.

Expression of microRNA Predicts Cardiovascular Events in Patients with Stable Coronary Artery Disease.

BACKGROUND: New biomarkers are warranted to identify patients with coronary artery disease (CAD) at high risk of recurrent cardiovascular events. It has been reported that the expression of microRNAs (miRs) may influence the development of CAD. OBJECTIVES: We aimed to investigate whether the expression of selected candidate miRs is a predictor of cardiovascular events in a cohort of stable CAD patients. METHODS: We performed a single-center prospective study of 749 stable CAD patients with a median follow-up of 2.8 years. We investigated the expression of nine candidate miRs and their relation to cardiovascular events in this cohort. The primary endpoint was the composite of nonfatal myocardial infarction (MI), stent thrombosis (ST), ischemic stroke, and cardiovascular death. The composite of nonfatal MI and ST was analyzed as a secondary endpoint. Furthermore, nonfatal MI, ST, ischemic stroke, and all-cause mortality were analyzed as individual endpoints. RESULTS: Employing receiver operating characteristic curves, it was shown that compared with traditional cardiovascular risk factors alone, combining the expression of miR-223-3p with existing traditional cardiovascular risk factors increased the predictive value of ST (area under the curve: 0.88 vs. 0.77, p = 0.04), the primary composite endpoint (0.65 vs. 0.61, p = 0.049), and the secondary endpoint of the composite of nonfatal MI and ST (0.68 vs. 0.62, p = 0.04). CONCLUSION: Among patients with CAD, adding miR-223-3p expression to traditional cardiovascular risk factors may improve prediction of cardiovascular events, particularly ST. Clinical trials confirming these findings are warranted.

Advanced Flow Cytometry Using the SYTO-13 Dye for the Assessment of Platelet Reactivity and Maturity in Whole Blood.

Newly produced immature platelets are larger, contain higher amounts of residual RNA, and are more reactive than mature platelets. Flow cytometry using the SYTO-13 dye is a method for the subdivision of immature platelets from mature platelets based on the labelling of intracellular platelet RNA, enabling the simultaneous investigation of the reactivity of each platelet population. This method provides detailed information on several aspects of platelet physiology using a combination of platelet surface markers and agonists. Currently, no standardized protocol exists across laboratories. Here, we describe a flow cytometry protocol in detail to investigate platelet reactivity and its relation to platelet maturity. We analyzed 20 healthy individuals with the protocol and compared the platelet subpopulation with the highest SYTO-13 labelling (in the first quintile, "SYTO-high") corresponding to the most immature platelets (highest RNA content) with the platelet subpopulation with the lowest SYTO-13 labelling (in the fifth quintile, "SYTO-low") corresponding to the mature platelets with the lowest RNA content. SYTO-high platelets had overall significantly increased platelet reactivity compared with that of SYTO-low platelets. The presented method may be a valuable research tool for the analysis of platelet reactivity and its relation to platelet maturity.

Antithrombotic treatment beyond 1 year after percutaneous coronary intervention in patients with atrial fibrillation.

AIMS: Beyond 1 year after percutaneous coronary intervention (PCI), guidelines recommend anticoagulant monotherapy in patients with atrial fibrillation (AF) rather than dual therapy with an anticoagulant and an antiplatelet drug. The risks and benefits of this strategy, however, remain uncertain. We examined hospitalization for bleeding and ischaemic risk beyond 1 year after PCI in patients with AF treated with monotherapy vs. dual therapy. Furthermore, among patients treated with monotherapy, we compared direct oral anticoagulant (DOAC) therapy and vitamin K antagonist (VKA) therapy. METHODS AND RESULTS: We included all patients with AF undergoing first-time PCI between 2003 and 2017 from the Western Denmark Heart Registry and followed them for up to 4 years. Follow-up started 15 months after PCI to enable assessment of medical treatment after 12 months. Using a Cox regression model, we computed weighted hazard ratios (HRw) of hospitalization for bleeding and major adverse cardiac events (MACEs). Analyses comparing monotherapy vs. dual therapy included 3331 patients, and analyses comparing DOAC vs. VKA monotherapy included 1275 patients. Risks of hospitalization for bleeding [HRw 0.90, 95% confidence interval (CI) 0.75-1.09] and MACE (HRw 1.04, 95% CI 0.90-1.19) were similar with monotherapy and dual therapy. Similarly, risks of hospitalization for bleeding (HRw 1.27, 95% CI 0.84-1.92) and MACE (HRw 1.15, 95% CI 0.87-1.50) were equal with DOAC and VKA monotherapy. CONCLUSION: Our results support long-term OAC monotherapy beyond 1 year after PCI in patients with atrial fibrillation and suggest that DOAC monotherapy is as safe and effective as VKA monotherapy.

Haemostasis and fibrinolysis after regular high-intensity interval training in patients with coronary artery disease: a randomised controlled trial.

IntroductionPatients with coronary artery disease (CAD) have prothrombotic changes compared with healthy individuals. Regular exercise reduces cardiovascular mortality in patients with stable CAD. However, the underlying mechanism for the beneficial effect is unknown. We investigated whether regular exercise would inhibit platelet aggregation and thrombin generation and increase fibrinolysis in patients with CAD. MATERIALS AND METHODS: Patients with CAD were randomised 1:1 to a supervised high-intensity exercise training programme or standard care for 12 weeks. Blood samples were obtained at baseline and after 6 and 12 weeks. Platelet aggregation was evaluated with the Multiplate Analyser, thrombin generation using the calibrated automated thrombogram and fibrinolysis employing a clot lysis assay. RESULTS: A total of 169 stable patients with CAD were randomised, and 142 patients (67±9 years, 83% males) completed the study; 64 in the exercise group and 78 in the standard care group. All but one patients received single antiplatelet therapy. From baseline to 12 weeks postintervention (Δ), no significant between-group differences were found in adenosine diphosphate-induced platelet aggregation (Δ-15 aggregation units (AU), AU×min, 95% CI -70 to 40 in the exercise group and Δ-26 AU×min, 95% CI -77 to 26 in the standard care group, p=0.44); endogenous thrombin potential (medians: Δ-5%, 95% CI -12 to 3 in the exercise group and Δ-6%, 95% CI -13 to 1 in the standard care group, p=0.26); nor in 50% clot lysis time (medians: Δ-9%, 95% CI -23 to 7 in the exercise group and Δ-17%, 95% CI -29 to -3 in the standard care group, p=0.60). CONCLUSIONS: Twelve weeks of high-intensity whole-body endurance exercise did not affect platelet aggregation, thrombin generation or fibrinolysis in patients with stable CAD. TRIAL REGISTRATION NUMBER: NCT04268992.

Feasibility and impact of whole-body high-intensity interval training in patients with stable coronary artery disease: a randomised controlled trial.

Exercise training reduces cardiovascular mortality and improves quality of life in CAD patients. We investigated the feasibility and impact of 12 weeks of low-volume high-intensity interval training (HIIT) in CAD-patients. Patients with stable CAD were randomized 1:1 to supervised HIIT or standard care. HIIT sessions were completed three times weekly for 12 weeks on a rowing ergometer. Before and after the 12-week intervention, patients completed a physiological evaluation of cardiorespiratory performance and quality of life questionnaires. Mixed model analysis was used to evaluate differences between and within groups. A total of 142 patients (67 ± 9 years, nHIIT = 64, nStandard care = 78) completed the trial. Training adherence was 97% (range 86-100%). Six patients dropped out because of non-fatal adverse events. Weekly training duration was 54 min with an average power output of 138 W. HIIT increased peak oxygen uptake by 2.5 mL/kg/min (95% CI 2.1-3.0), whereas no change was observed in standard care (0.2 mL/kg/min, 95% CI - 0.2-0.6, P < 0.001). In addition, HIIT improved markers of quality of life, including physical functioning, limitations due to physical illness, general health and vitality (P < 0.05). Twelve weeks of low-volume whole-body HIIT increased cardiorespiratory capacity and improved quality of life in patients with stable CAD compared to standard care. In addition, our study demonstrates that the applied vigorous training regime is feasible for this patient group.Clinical trial registration: www.clinicaltrials.gov . Identification number: NCT04268992.

Minimally invasive treatment of left main coronary artery thrombosis in a young patient with COVID-19.

COVID-19 has been associated with cardiovascular events. This case demonstrates severe left main coronary artery thrombosis with distal embolisation in a young male patient admitted with COVID-19 who developed ST-elevation myocardial infarction. The patient was treated with thrombus aspiration combined with aggressive anticoagulant treatment, which yielded complete resolution of the thrombus. Left main thrombus represents a life-threatening coronary event and is most often associated with atherosclerotic plaque rupture. In this case, however, we suspect that COVID-19-related intimal inflammation and hypercoagulopathy might be the causal mechanism of thrombus formation. Revascularisation with coronary artery bypass grafting or percutaneous coronary intervention is the standard treatment of left main thrombosis. However, due to the patient's young age and lack of significant atherosclerotic disease burden, we used a conservative medical treatment strategy using potent antithrombotic therapy.

Cytoreductive treatment and association with platelet function and maturity in patients with essential thrombocythaemia.

Patients with essential thrombocythaemia (ET) have an increased risk of thromboembolic events, which may differ according to different cytoreductive drugs. We investigated the effect of cytoreductive treatment on platelet function and turnover in ET patients. Blood samples were obtained at 1 and 24 h after aspirin intake. Platelet function was evaluated by platelet aggregation and flow cytometry. Platelet turnover was assessed by immature platelet count, immature platelet fraction (IPF) and mean platelet volume (MPV). A total of 47 ET patients were included and grouped into 21 patients not receiving cytoreductive treatment, 15 patients receiving hydroxycarbamide and 11 patients receiving pegylated interferon alpha (peg-IFN). Patients receiving peg-IFN had significantly higher IPF and MPV than the other ET groups. Patients not receiving cytoreductive treatment had significantly higher platelet aggregation 24 h after aspirin intake than the other ET groups (p-values from 0.03 to 0.0002). Patients receiving hydroxycarbamide had significantly higher expression of platelet granule makers, P-selectin and CD63, than patients receiving peg-IFN (p-values ≤0.003). Cytoreduction provides more consistent platelet inhibition compared with no cytoreductive treatment. Moreover, peg-IFN provides superior inhibition of platelet activation markers than hydroxycarbamide, which in part may explain differences in risk of thromboembolic events in ET patients.

Flow Cytometric Assessment of Changes in Platelet Reactivity after Acute Coronary Syndrome: A Systematic Review.

Increased platelet activity is an important predictor for recurrent cardiovascular events in patients with acute coronary syndromes (ACS). Flow cytometry is an advanced method for evaluation of platelet activity. We aimed to summarize the current literature on dynamic changes in platelet activity analyzed by flow cytometry in patients with ACS. Employing the guidelines of Preferred Report Items for Systematic Reviews and Meta-Analyses (PRISMA), we searched PubMed and Embase on October 26, 2021, and identified studies measuring platelet activity with flow cytometry in ACS patients in the acute phase (baseline) and at follow-up in a more stable phase. In the 12 included studies, fibrinogen receptor, α-granule secretion, platelet reactivity index, monocyte-platelet aggregates, neutrophil-platelet aggregates, and reticulated platelets were measured. The fibrinogen receptor and α-granule secretion were either unchanged or lower during follow-up measurements than in the acute phase. Platelet reactivity index showed inconsistent results. Values of monocyte-platelet aggregates and neutrophil-platelet aggregates were lower at follow-up than at baseline (p-values <0.05). Reticulated platelets were either unchanged (p-value >0.64) or lower at 1 to 2 months follow-up (p-value 0.04), and also lower at 5 months to 1-year follow-up (p-value >0.005) compared with baseline. Overall, flow cytometric analyses of platelet function in ACS patients showed that platelet activity was lower at follow-up than at baseline. However, in some patients, platelet activity remained unchanged from baseline to follow-up, possibly indicating a sustained high platelet activity that may increase the risk of recurrent cardiovascular events.

Effectiveness and Safety of Ticagrelor Implementation in Patients with Acute Coronary Syndrome undergoing Percutaneous Coronary Intervention: A Cohort Study in Western Denmark.

BACKGROUND: Ticagrelor was introduced in Denmark in 2011 after randomised data showed its superiority over clopidogrel for patients with acute coronary syndrome (ACS). We assessed the effectiveness and safety of ticagrelor implementation in ACS patients undergoing percutaneous coronary intervention (PCI). METHODS: We identified PCI-treated ACS patients in Western Denmark who redeemed a P2Y12 inhibitor prescription within 14 days. Using Danish health registries, 1-year outcomes were compared before (2007-2010) and after (2012-2015) introduction of ticagrelor. Outcomes were MACE (death, myocardial infarction, and ischaemic stroke) and hospitalisation for bleeding. Inverse probability of treatment weights were used to estimate weighted incidence rate ratios (wIRRs). FINDINGS: We included 14,450 patients; 7,102 were treated in the earlier time period (99·9% clopidogrel) and 7,348 in the later time period (87·8% ticagrelor). Ticagrelor implementation was not associated with a clinically relevant difference in 1-year risk of MACE with 413 events in the ticagrelor period vs. 424 events in the clopidogrel period (cumulative incidence percentage [CIP] 5·6% vs. 6·0%; wIRR 1·06, 95% CI 0·92-1·22). The 1-year risk of bleeding was also similar between groups with 335 bleedings requiring hospitalisation in the ticagrelor period vs. 309 events in the clopidogrel period (CIP 4·6% vs. 4·4%; wIRR 1·05, 95% CI 0·89-1·23). Results were robust in patients above and below 70 years of age. INTERPRETATION: Implementation of ticagrelor was not associated with changes in risks of ischaemic or bleeding events in Danish PCI-treated ACS patients.

Association of whole blood microRNA expression with platelet function and turnover in patients with coronary artery disease.

INTRODUCTION: The risk of recurrent cardiovascular events in patients with coronary artery disease (CAD) is determined by multiple factors including platelet function and turnover. MicroRNAs (miRs) may regulate both platelet function and turnover. We aimed to identify candidate miRs associating with platelet function and turnover in a cohort of stable CAD patients. Furthermore, we retrieved information on binding targets of the candidate miRs to obtain a more comprehensive biological insight into miR regulation of platelet function and turnover. METHODS: Based on existing literature and a pilot study, we identified nine candidate miRs. Subsequently, we investigated the expression of the candidate miRs in whole blood and their relation to platelet function and turnover in 749 CAD patients. Platelet function was analysed using impedance aggregometry, optical aggregometry and serum thromboxane B2 measurements. Platelet turnover markers (immature platelet count, immature platelet fraction and mean platelet volume) were measured using monochromatic automated flow cytometry. RESULTS: Expression of miR-93-5p, miR-126-3p, miR-150-5p, miR-423-3p and miR-1180-3p showed negative correlations with platelet function (p-values from <0.0001 to 0.0006, rho from -0.13 to -0.36). In addition, expression of miR-423-3p showed negative correlation with platelet turnover markers (p-values from 0.001 to 0.004, rho from -0.11 to -0.12). CONCLUSIONS: We identified several novel miRs that may regulate platelet function and turnover, thereby contributing to the increased risk of recurrent cardiovascular events in CAD patients.

Impact of diabetes on 1-year clinical outcome in patients undergoing revascularization with the BioFreedom stents or the Orsiro stents from the SORT OUT IX trial.

This sub-study of the SORT OUT IX trial sought to compare clinical outcomes between patients with diabetes randomized to implantation of either the polymer-free biolimus A9-coated BioFreedom stent (BF-BES) or the ultra-thin strut, biodegradable polymer sirolimus-eluting Orsiro stent (O-SES). Patients with diabetes have an increased risk of target lesion failure (TLF) after percutaneous coronary intervention (PCI). The impact of different stent types in patients with diabetes is still discussed. A total of 607 of the 3151 patients (19.3%) enrolled in the SORT OUT IX study had diabetes. Randomization was stratified by patients with/without diabetes; 304 received BF-BES and 303 O-SES. The primary endpoint was TLF, which was a composite of cardiac death, myocardial infarction (not related to other than the index lesion) and target lesion revascularization (TLR) within 1 year. After 1 year, patients with diabetes had higher TLF (7.2% vs. 3.7%, incidence rate ratio [IRR]: 1.65; 95% confidence interval [CI]: 1.08-2.50), than patients without diabetes. TLF did not differ significantly between BF-BES and O-SES in patients with diabetes (8.2% vs. 6.3%, IRR: 1.17; 95% CI: 0.63-2.20). In patients with diabetes, cardiac death occurred in 2.3% of BF-BES and in 3.6% of O-SES (IRR: 0.58; 95% CI: 0.23-1.45) and TLR occurred in 5.3% and 2.3% of BF-BES and O-SES, respectively (IRR: 2.12; 95% CI: 0.81-5.56). Definite stent thrombosis rates of 1.3% were found in both stent types. Patients with diabetes had higher 1-year TLF rate after PCI compared to patients without diabetes, whereas TLF did not differ significantly between the two stent types BF-BES and O-SES in patients with diabetes.