Where a licence is displayed above, please note the terms and conditions of the licence govern yo... more Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive.
Rivaroxaban is a non-vitamin K antagonist oral anticoagulant that acts as a direct factor Xa inhi... more Rivaroxaban is a non-vitamin K antagonist oral anticoagulant that acts as a direct factor Xa inhibitor, and is widely used for the prevention and treatment of thromboembolic disorders. As further knowledge gaps are identified in thrombosis management, the rivaroxaban research program has expanded in an attempt to elucidate the wider benefits of rivaroxaban. An increased understanding of the interactions taking place within the coagulation cascade may support a broader role for rivaroxaban (2.5 mg twice daily [bid] or 5 mg bid) in the setting of vascular protection, either alone or in combination with an antiplatelet agent. The aim of this article is to describe the potential role of rivaroxaban in the context of vascular protection and provide an overview of recently completed and ongoing randomized controlled trials of rivaroxaban in the areas of stroke prevention, venous protection and vascular protection.
Background: Many patients with atrial fibrillation have concomitant coronary artery disease with ... more Background: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in the need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes. Methods: Adults with newly diagnosed atrial fibrillation and ≥1 investigator-defined stroke risk factor were enrolled in GARFIELD-AF between Mar-2010 and Sep-2015. The association between prior acute coronary syndromes and long-term outcomes was determined using a Cox proportional hazards model, adjusting for baseline risk factors, OAC (oral anticoagulation) ± AP (antiplatelet therapy) and usual care. Results: 10.5% of 39,679 patients had a history of acute coronary syndromes. At 2-year followup, patients with prior acute coronary syndromes had a higher adjusted risks of stroke/systemic embolism (hazard ratio: 1.39, 95% confidence interval: 1.08-1.78), major bleeding (1.30, 0.95-1.79), all-cause mortality (1.34, 1.21-1.49), cardiovascular mortality (1.85, 1.51-2.26) and new acute coronary syndromes (3.42, 2.62-4.45). Comparing antithrombotic therapy in the acute coronary syndromes vs no acute coronary syndromes groups, most patients received OAC ± AP: 60.8% vs 66.1%, but AP therapy was more likely in the acute coronary syndromes group (68.1% vs 32.9%), either alone (34.9% vs 20.8%) or with OAC (33.2% vs 12.1%). Overall, 22.2% in the acute coronary syndromes group received dual AP therapy with (7.5%) or without OAC (14.7%). Among patients with moderate/high risk for stroke/systemic embolism, fewer in the acute coronary syndromes group received OAC with or without AP therapy (CHA 2 DS 2-VASc 2: 52.1%
Real-world data are a well-recognized component within the drug lifecycle, and such data are gene... more Real-world data are a well-recognized component within the drug lifecycle, and such data are generated from a range of sources and study designs, including claims databases, electronic health records, non-interventional studies (NIS) and registries. While this information can be of vital clinical importance, there may be challenges in understanding the relevance of the differing study designs, endpoints and populations. Here, we summarize the value of real-world evidence and considerations pertinent to their use in clinical research. Owing to the variety of analyses being conducted using real-world data, it is important for researchers and clinicians to have a clear understanding of the nature and origin of those data, and to ensure they are valid, reliable and robust in terms of extrapolating meaningful findings. There are crucial questions to address when evaluating real-world studies, and we introduce a checklist to meet these objectives. In addition to advice for appraising data...
Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) explored the impact ... more Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) explored the impact of gender, risk factors and anticoagulant (AC) treatment on 1-year outcomes in patients with non-valvular atrial fibrillation (NVAF). GARFIELD-AF is a prospective non-interventional registry. Investigator sites (n=1048) are representative of the care settings/locations in each of the 35 countries. Patients ≥18yrs with newly diagnosed (≤6 weeks' duration) NVAF and ≥1 investigator-determined stroke risk factors. Event rates per 100 person-years were estimated from the Poisson model and HRs and 95% CIs calculated. Of 28 624 patients (women 44.4%; men 55.6%) enrolled, there were more elderly (≥75 years) women (46.9%) than men (30.4%). All-cause mortality rates per 100 person-years (95% CI) for women and men were 4.48 (4.12 to 4.87) and 4.04 (3.74 to 4.38), respectively, stroke/systemic embolism (SE) (1.62 (1.41 to 1.87) and 1.17 (1.01 to 1.36)) and major bleeding (0.93 (0.78 to 1.13) and...
We studied evolving antithrombotic therapy patterns in patients with newly diagnosed non-valvular... more We studied evolving antithrombotic therapy patterns in patients with newly diagnosed non-valvular atrial fibrillation (AF) and ≥1 additional stroke risk factor between 2010 and 2015. 39 670 patients were prospectively enrolled in four sequential cohorts in the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF): cohort C1 (2010-2011), n=5500; C2 (2011-2013), n=11 662; C3 (2013-2014), n=11 462; C4 (2014-2015), n=11 046. Baseline characteristics and antithrombotic therapy initiated at diagnosis were analysed by cohort. Baseline characteristics were similar across cohorts. Median CHA2DS2-VASc (cardiac failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled)-vascular disease, age 65-74 and sex category (female)) score was 3 in all four cohorts. From C1 to C4, the proportion of patients on anticoagulant (AC) therapy increased by almost 15% (C1 57.4%; C4 71.1%). Use of vitamin K antagonist (VKA)±antiplatelet (AP) (C1 53.2%; C4 34.0%) and AP monotherapy...
Atrial fibrillation (AF) is the most common arrhythmia worldwide. The prevalence of AF in persons... more Atrial fibrillation (AF) is the most common arrhythmia worldwide. The prevalence of AF in persons older than 55 years is at least 33.5 million globally and is predicted to more than double in the next half-century. Anticoagulation, heart rate control, and heart rhythm control comprise the 3 main treatment strategies in AF. Anticoagulation is aimed at preventing debilitating stroke, systemic embolism, and associated mortality. Historically, anticoagulation in AF was achieved with a vitamin K antagonist such as warfarin, which is supported by evidence demonstrating reduced incident stroke and all-cause mortality. However, warfarin has unpredictable pharmacokinetics with many drug-drug interactions that require regular monitoring to ensure patients remain in the therapeutic anticoagulant range. Non-vitamin K antagonist oral anticoagulants including dabigatran, rivaroxaban, apixaban, and edoxaban provide a possible solution to these issues with their more predictable pharmacokinetics, rapid onset of action, and greater specificity. Results from large randomized, controlled trials indicate that these agents are at least noninferior to warfarin in prevention of stroke. These trials also demonstrate a consistently lower incidence of intracranial hemorrhage, almost always all lifethreatening bleeds, and many forms of major bleeds with the possible exception of gastrointestinal and some other forms of mucosal bleeding, compared with warfarin. Patients with AF are a heterogeneous population with diverse risk of stroke and bleeding, and different subgroups respond differently to anticoagulation. Important clinical questions have arisen regarding optimal anticoagulation drug selection in distinct populations such as those with renal impairment, older age, coronary artery disease, and heart failure as well as those at particularly high risk for bleeding or thromboembolism. In this review, treatment strategies in AF management are discussed in the context of different individual subgroups of patients.
Aims Although non-vitamin K antagonist oral anticoagulants are recommended for stroke prevention ... more Aims Although non-vitamin K antagonist oral anticoagulants are recommended for stroke prevention in patients with non-valvular atrial fibrillation (NVAF) based on clinical trial results, there is a need for safety and efficacy data from unselected patients in everyday clinical practice. XANTUS investigated the safety and efficacy of the Factor Xa inhibitor rivaroxaban in routine clinical use in the NVAF setting. Methods and results Consecutive consenting patients with NVAF newly started on rivaroxaban were eligible and were followed up at 3-month intervals for 1 year, or for at least 30 days after permanent discontinuation. All adverse events (AEs) were recorded as AEs or serious AEs; major outcomes (including major bleeding, symptomatic thromboembolic events [stroke, systemic embolism, transient ischaemic attack, and myocardial infarction], and all-cause death) were centrally adjudicated. There were 6784 patients treated with rivaroxaban at 311 centres in Europe, Israel, and Canada. Mean patient age was 71.5 years (range 19-99), 41% were female, and 9.4% had documented severe or moderate renal impairment (creatinine clearance ,50 mL/min). The mean CHADS 2 and CHA 2 DS 2-VASc scores were 2.0 and 3.4, respectively; 859 (12.7%) patients had a CHA 2 DS 2-VASc score of 0 or 1. The mean treatment duration was 329 days. Treatment-emergent major bleeding occurred in 128 patients (2.1 events per 100 patient-years), 118 (1.9 events per 100 patient-years) died, and 43 (0.7 events per 100 patient-years) suffered a stroke. Conclusion XANTUS is the first international, prospective, observational study to describe the use of rivaroxaban in a broad NVAF patient population. Rates of stroke and major bleeding were low in patients receiving rivaroxaban in routine clinical practice. Trial registration number Clinicaltrials.gov: NCT01606995.
Non-vitamin K antagonist oral anticoagulants (NOACs) are efficacious and safe antithrombotic drug... more Non-vitamin K antagonist oral anticoagulants (NOACs) are efficacious and safe antithrombotic drugs but the non-availability of an antidote for potential fatal haemorrhagic events is clinically perceived as a strong limitation. We aimed at evaluating the risk of haemorrhage-related fatalities associated with NOACs in patients requiring long-term anticoagulation. MEDLINE, Cochrane Library and Web of Science databases were searched in November 2014 for atrial fibrillation (AF) or venous thromboembolism (VTE) phase III randomised controlled trials (RCT) comparing NOACs with vitamin K antagonists (VKAs) or low molecular weight heparin (LMWH) followed by VKAs. Pooled OR and 95% CIs were estimated through meta-analysis. Heterogeneity was assessed with the I(2) test. Eleven studies were included: 5 on AF and 6 on VTE. A total of 100 324 patients were evaluated in 4 rivaroxaban, 3 dabigatran, 2 apixaban and 2 edoxaban studies. NOAC-treated patients had a 47% odds reduction compared with VKA ...
Early versions of the implantable cardioverter defibrillator (ICD) were simple nonprogrammable de... more Early versions of the implantable cardioverter defibrillator (ICD) were simple nonprogrammable devices, the limitations of which were obvious. Over the last 10 years, rapid technical develop-ment of the ICD has led to the current third genera-tion devices with ...
Where a licence is displayed above, please note the terms and conditions of the licence govern yo... more Where a licence is displayed above, please note the terms and conditions of the licence govern your use of this document. When citing, please reference the published version. Take down policy While the University of Birmingham exercises care and attention in making items available there are rare occasions when an item has been uploaded in error or has been deemed to be commercially or otherwise sensitive.
Rivaroxaban is a non-vitamin K antagonist oral anticoagulant that acts as a direct factor Xa inhi... more Rivaroxaban is a non-vitamin K antagonist oral anticoagulant that acts as a direct factor Xa inhibitor, and is widely used for the prevention and treatment of thromboembolic disorders. As further knowledge gaps are identified in thrombosis management, the rivaroxaban research program has expanded in an attempt to elucidate the wider benefits of rivaroxaban. An increased understanding of the interactions taking place within the coagulation cascade may support a broader role for rivaroxaban (2.5 mg twice daily [bid] or 5 mg bid) in the setting of vascular protection, either alone or in combination with an antiplatelet agent. The aim of this article is to describe the potential role of rivaroxaban in the context of vascular protection and provide an overview of recently completed and ongoing randomized controlled trials of rivaroxaban in the areas of stroke prevention, venous protection and vascular protection.
Background: Many patients with atrial fibrillation have concomitant coronary artery disease with ... more Background: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in the need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes. Methods: Adults with newly diagnosed atrial fibrillation and ≥1 investigator-defined stroke risk factor were enrolled in GARFIELD-AF between Mar-2010 and Sep-2015. The association between prior acute coronary syndromes and long-term outcomes was determined using a Cox proportional hazards model, adjusting for baseline risk factors, OAC (oral anticoagulation) ± AP (antiplatelet therapy) and usual care. Results: 10.5% of 39,679 patients had a history of acute coronary syndromes. At 2-year followup, patients with prior acute coronary syndromes had a higher adjusted risks of stroke/systemic embolism (hazard ratio: 1.39, 95% confidence interval: 1.08-1.78), major bleeding (1.30, 0.95-1.79), all-cause mortality (1.34, 1.21-1.49), cardiovascular mortality (1.85, 1.51-2.26) and new acute coronary syndromes (3.42, 2.62-4.45). Comparing antithrombotic therapy in the acute coronary syndromes vs no acute coronary syndromes groups, most patients received OAC ± AP: 60.8% vs 66.1%, but AP therapy was more likely in the acute coronary syndromes group (68.1% vs 32.9%), either alone (34.9% vs 20.8%) or with OAC (33.2% vs 12.1%). Overall, 22.2% in the acute coronary syndromes group received dual AP therapy with (7.5%) or without OAC (14.7%). Among patients with moderate/high risk for stroke/systemic embolism, fewer in the acute coronary syndromes group received OAC with or without AP therapy (CHA 2 DS 2-VASc 2: 52.1%
Real-world data are a well-recognized component within the drug lifecycle, and such data are gene... more Real-world data are a well-recognized component within the drug lifecycle, and such data are generated from a range of sources and study designs, including claims databases, electronic health records, non-interventional studies (NIS) and registries. While this information can be of vital clinical importance, there may be challenges in understanding the relevance of the differing study designs, endpoints and populations. Here, we summarize the value of real-world evidence and considerations pertinent to their use in clinical research. Owing to the variety of analyses being conducted using real-world data, it is important for researchers and clinicians to have a clear understanding of the nature and origin of those data, and to ensure they are valid, reliable and robust in terms of extrapolating meaningful findings. There are crucial questions to address when evaluating real-world studies, and we introduce a checklist to meet these objectives. In addition to advice for appraising data...
Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) explored the impact ... more Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) explored the impact of gender, risk factors and anticoagulant (AC) treatment on 1-year outcomes in patients with non-valvular atrial fibrillation (NVAF). GARFIELD-AF is a prospective non-interventional registry. Investigator sites (n=1048) are representative of the care settings/locations in each of the 35 countries. Patients ≥18yrs with newly diagnosed (≤6 weeks' duration) NVAF and ≥1 investigator-determined stroke risk factors. Event rates per 100 person-years were estimated from the Poisson model and HRs and 95% CIs calculated. Of 28 624 patients (women 44.4%; men 55.6%) enrolled, there were more elderly (≥75 years) women (46.9%) than men (30.4%). All-cause mortality rates per 100 person-years (95% CI) for women and men were 4.48 (4.12 to 4.87) and 4.04 (3.74 to 4.38), respectively, stroke/systemic embolism (SE) (1.62 (1.41 to 1.87) and 1.17 (1.01 to 1.36)) and major bleeding (0.93 (0.78 to 1.13) and...
We studied evolving antithrombotic therapy patterns in patients with newly diagnosed non-valvular... more We studied evolving antithrombotic therapy patterns in patients with newly diagnosed non-valvular atrial fibrillation (AF) and ≥1 additional stroke risk factor between 2010 and 2015. 39 670 patients were prospectively enrolled in four sequential cohorts in the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF): cohort C1 (2010-2011), n=5500; C2 (2011-2013), n=11 662; C3 (2013-2014), n=11 462; C4 (2014-2015), n=11 046. Baseline characteristics and antithrombotic therapy initiated at diagnosis were analysed by cohort. Baseline characteristics were similar across cohorts. Median CHA2DS2-VASc (cardiac failure, hypertension, age ≥75 (doubled), diabetes, stroke (doubled)-vascular disease, age 65-74 and sex category (female)) score was 3 in all four cohorts. From C1 to C4, the proportion of patients on anticoagulant (AC) therapy increased by almost 15% (C1 57.4%; C4 71.1%). Use of vitamin K antagonist (VKA)±antiplatelet (AP) (C1 53.2%; C4 34.0%) and AP monotherapy...
Atrial fibrillation (AF) is the most common arrhythmia worldwide. The prevalence of AF in persons... more Atrial fibrillation (AF) is the most common arrhythmia worldwide. The prevalence of AF in persons older than 55 years is at least 33.5 million globally and is predicted to more than double in the next half-century. Anticoagulation, heart rate control, and heart rhythm control comprise the 3 main treatment strategies in AF. Anticoagulation is aimed at preventing debilitating stroke, systemic embolism, and associated mortality. Historically, anticoagulation in AF was achieved with a vitamin K antagonist such as warfarin, which is supported by evidence demonstrating reduced incident stroke and all-cause mortality. However, warfarin has unpredictable pharmacokinetics with many drug-drug interactions that require regular monitoring to ensure patients remain in the therapeutic anticoagulant range. Non-vitamin K antagonist oral anticoagulants including dabigatran, rivaroxaban, apixaban, and edoxaban provide a possible solution to these issues with their more predictable pharmacokinetics, rapid onset of action, and greater specificity. Results from large randomized, controlled trials indicate that these agents are at least noninferior to warfarin in prevention of stroke. These trials also demonstrate a consistently lower incidence of intracranial hemorrhage, almost always all lifethreatening bleeds, and many forms of major bleeds with the possible exception of gastrointestinal and some other forms of mucosal bleeding, compared with warfarin. Patients with AF are a heterogeneous population with diverse risk of stroke and bleeding, and different subgroups respond differently to anticoagulation. Important clinical questions have arisen regarding optimal anticoagulation drug selection in distinct populations such as those with renal impairment, older age, coronary artery disease, and heart failure as well as those at particularly high risk for bleeding or thromboembolism. In this review, treatment strategies in AF management are discussed in the context of different individual subgroups of patients.
Aims Although non-vitamin K antagonist oral anticoagulants are recommended for stroke prevention ... more Aims Although non-vitamin K antagonist oral anticoagulants are recommended for stroke prevention in patients with non-valvular atrial fibrillation (NVAF) based on clinical trial results, there is a need for safety and efficacy data from unselected patients in everyday clinical practice. XANTUS investigated the safety and efficacy of the Factor Xa inhibitor rivaroxaban in routine clinical use in the NVAF setting. Methods and results Consecutive consenting patients with NVAF newly started on rivaroxaban were eligible and were followed up at 3-month intervals for 1 year, or for at least 30 days after permanent discontinuation. All adverse events (AEs) were recorded as AEs or serious AEs; major outcomes (including major bleeding, symptomatic thromboembolic events [stroke, systemic embolism, transient ischaemic attack, and myocardial infarction], and all-cause death) were centrally adjudicated. There were 6784 patients treated with rivaroxaban at 311 centres in Europe, Israel, and Canada. Mean patient age was 71.5 years (range 19-99), 41% were female, and 9.4% had documented severe or moderate renal impairment (creatinine clearance ,50 mL/min). The mean CHADS 2 and CHA 2 DS 2-VASc scores were 2.0 and 3.4, respectively; 859 (12.7%) patients had a CHA 2 DS 2-VASc score of 0 or 1. The mean treatment duration was 329 days. Treatment-emergent major bleeding occurred in 128 patients (2.1 events per 100 patient-years), 118 (1.9 events per 100 patient-years) died, and 43 (0.7 events per 100 patient-years) suffered a stroke. Conclusion XANTUS is the first international, prospective, observational study to describe the use of rivaroxaban in a broad NVAF patient population. Rates of stroke and major bleeding were low in patients receiving rivaroxaban in routine clinical practice. Trial registration number Clinicaltrials.gov: NCT01606995.
Non-vitamin K antagonist oral anticoagulants (NOACs) are efficacious and safe antithrombotic drug... more Non-vitamin K antagonist oral anticoagulants (NOACs) are efficacious and safe antithrombotic drugs but the non-availability of an antidote for potential fatal haemorrhagic events is clinically perceived as a strong limitation. We aimed at evaluating the risk of haemorrhage-related fatalities associated with NOACs in patients requiring long-term anticoagulation. MEDLINE, Cochrane Library and Web of Science databases were searched in November 2014 for atrial fibrillation (AF) or venous thromboembolism (VTE) phase III randomised controlled trials (RCT) comparing NOACs with vitamin K antagonists (VKAs) or low molecular weight heparin (LMWH) followed by VKAs. Pooled OR and 95% CIs were estimated through meta-analysis. Heterogeneity was assessed with the I(2) test. Eleven studies were included: 5 on AF and 6 on VTE. A total of 100 324 patients were evaluated in 4 rivaroxaban, 3 dabigatran, 2 apixaban and 2 edoxaban studies. NOAC-treated patients had a 47% odds reduction compared with VKA ...
Early versions of the implantable cardioverter defibrillator (ICD) were simple nonprogrammable de... more Early versions of the implantable cardioverter defibrillator (ICD) were simple nonprogrammable devices, the limitations of which were obvious. Over the last 10 years, rapid technical develop-ment of the ICD has led to the current third genera-tion devices with ...
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