Dabigatran vs. warfarin in relation to the presence of left ventricular hypertrophy in patients with atrial fibrillation- the Randomized Evaluation of Long-term anticoagulation therapY (RE-LY) study

Effectiveness of Novel Oral Anticoagulants Versus Warfarin in Patients With Atrial Fibrillation: A Systematic Review and Meta-Analysis

Atrial fibrillation (AF) is a common cardiac arrhythmia associated with an increased risk of stroke and systemic embolism (SE). Anticoagulation therapy, particularly with vitamin K antagonists (VKA) or novel oral anticoagulants (NOACs), is essential for stroke prevention in patients with AF. However, the comparative effectiveness of NOACs and warfarin remains debatable. Of the 34 studies included, 14 studies involving 166,845 patients were included in the meta-analysis and 20 studies were included in the systematic review. Our findings indicate that NOACs were associated with a significantly lesser risk of stroke/SE with a relative risk (RR) of 0.84 and p=0.0005, and all-cause mortality RR=0.88 and p=0.006. There were no significant differences between major bleeding events with an RR of 0.87 and p=0.22, and serious adverse events (SAE) with RR=1.01 and p=0.35, compared to warfarin in patients with AF. Our meta-analysis demonstrates strong evidence for the superiority in reducing stroke/SE and all-cause mortality of NOACs compared to warfarin. However, no significant differences were identified in the bleeding outcomes or SAEs between the two groups.

The efficacy and safety of direct oral anticoagulants compared with vitamin K antagonist in patients with hypertrophic cardiomyopathy and atrial fibrillation

BACKGROUND

The benefit-risk profile of direct oral anticoagulants (DOAC) therapy in patients with hypertrophic cardiomyopathy (HCM) and atrial fibrillation (AF) has not been well established yet. This study aimed to evaluate the efficacy and safety of DOAC compared with vitamin K antagonists (VKA) in patients with HCM and AF.

METHODS

PubMed, EMBASE, the Cochrane Library, and clinicaltrials.gov were searched to identify studies comparing DOAC with VKA in patients with HCM and AF. The primary endpoint was thromboembolic events. The relative risks and standard errors were pooled by random-effect models using the generic inverse variance method.

RESULTS

Seven observational studies involving 9395 patients were included in this meta-analysis. Compared to the VKA group, the DOAC group displayed a similar risk of thromboembolic events [RR (95%CI): 0.93 (0.73-1.20), p = 0.59] and ischemic stroke [RR (95%CI): 0.65 (0.33-1.28), p = 0.22]. The incidence of major bleeding was comparable between the two groups [RR (95%CI): 0.75 (0.49-1.15), p = 0.19]. Meanwhile, DOAC therapy was superior to VKA therapy in reducing the incidences of all-cause death [RR (95%CI): 0.44 (0.35-0.55), p < 0.001], cardiovascular death [RR (95%CI): 0.41 (0.22-0.75), p = 0.004], and intracranial hemorrhage [RR (95%CI): 0.42 (0.24-0.74), p = 0.003].

CONCLUSION

In patients with HCM and AF, DOAC therapy was similar to VKA therapy in reducing the risk of thromboembolic events, without increasing bleeding risk. In addition, the DOAC group displayed significant advantages in reducing mortality and intracranial hemorrhage compared with the VKA group. Further randomized controlled trials are needed to provide more evidence for DOAC therapy in this population.

Does Predation Exacerbate the Risk of Endosymbiont Loss in Heat Stressed Hermatypic Corals? Molecular Cues Provide Insights Into Species-Specific Health Outcomes in a Multi-Stressor Ocean

Ocean warming has been a major driver of coral reef bleaching and mass mortality. Coupled to other biotic pressures, corals’ ability for acclimatization and adaptation may become compromised. Here, we tested the combined effects of warming scenarios (26, 30, and 32°C) and predation (wound vs. no wound) in coral health condition (paleness, bleaching, and mortality), cellular stress responses (heat shock protein 70 kDa Hsp70, total ubiquitin Ub, and total antioxidant capacity TAC), and physiological state (integrated biomarker response index, IBR) of seven Scleractinian coral species, after being exposed for 60 days. Results show that although temperature was the main factor driving coral health condition, thermotolerant species (Galaxea fascicularis, Psammocora contigua, and Turbinaria reniformis) displayed increased paleness, bleaching, and mortality in predation treatments at high temperature, whereas thermosensitive species (Acropora tenuis, Echinopora lamellosa, and Montipora capricornis brown and green morphotypes) all died at 32°C, regardless of predation condition. At the molecular level, results show that there were significant main and interactive effects of species, temperature, and predation in the biomarkers assessed. Temperature affected Hsp70, Ub, and TAC, evidencing the role of protein folding and turnover, as well as reactive oxygen species scavenging in heat stress management. Predation increased Hsp70 and Ub, suggesting the activation of the pro-phenoloxidase system and cytokine activity, whereas the combination of both stressors mainly affected TAC during moderate stress and Ub under severe stress, suggesting that redox balance and defense of homeostasis are crucial in tissue repair at high temperature. IBR levels showed an increasing trend at 32°C in predated coral fragments (although non-significant). We conclude that coral responses to the combination of high temperature and predation pressure display high inter-species variability, but these stressors may pose a higher risk of endosymbiont loss, depending on species physiology and stress intensity.

Efficacy and safety of direct oral anticoagulants (DOACs) versus vitamin K antagonist (VKA) among patients with atrial fibrillation and hypertrophic cardiomyopathy: a systematic review and meta-analysis

Background/objectives: Long-term oral anticoagulant therapy is recommended for patients with hypertrophic cardiomyopathy (HCM) who develop atrial fibrillation (AF) to prevent cardioembolic complications. In patients with non-valvular AF, direct oral anticoagulants (DOACs) has been proved to be non-inferior to adjusted-dose vitamin K antagonist (VKA). However, the role of DOACs in patients with AF in the setting of HCM has not been fully established.Methods: A comprehensive literature review was conducted by searching for published articles indexed in MEDLINE and EMBASE databases from inception through 1 May 2019. Eligible studies must start with recruitment of patients with AF in the setting of HCM who received either DOACs or VKA. The studies must follow them for the occurrence of ischaemic stroke. Hazard ratio (HR) and confidence interval (CI) of developing ischaemic stroke between the two groups must be reported. Pooled HR was calculated using a random-effect, generic inverse variance method of DerSimonian and Laird.Results: A total of three retrospective cohort studies with 4,418 participants met the eligibility criteria and were included into the meta-analysis. A significantly lower risk of all-cause death was observed in the DOACs group than in the VKA group with the pooled HR of 0.43 (95% CI, 0.33-0.58, I² = 0%). However, the risk of ischaemic stroke among patients with AF and HCM who received DOACs was not significantly different from those who received VKA with the pooled HR of 0.95 (95% CI, 0.73-1.22, I² = 0%). Both major bleeding and intracranial bleeding were also not significantly different between those who received DOACs versus those who received VKA with the pooled HR of 0.94 (95% CI, 0.70-1.26, I² = 0%) and 0.61 (95% CI, 0.27-1.37, I² = 0%), respectively.Conclusions: The current study found that the risk of all-cause death was significantly reduced but the risk of ischaemic stroke, major bleeding and intracranial bleeding were not significantly different between patients with AF and HCM who had received DOACs and those who received VKA.

Non-vitamin K antagonist oral anticoagulants in patients with hypertrophic cardiomyopathy and atrial fibrillation: a systematic review and meta-analysis

Several studies have explored the use of NOACs compared with vitamin K antagonists (VKAs) in patients with hypertrophic cardiomyopathy (HCM) and atrial fibrillation (AF); and therefore, we aimed to compare the efficacy and safety outcomes of NOACs with VKAs in this population. We systematically searched the PubMed and Embase databases until August 5, 2019 for studies that compared the effect of NOACs with VKAs in patients with HCM and AF. The risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. A total of four observational studies were included in this meta-analysis. Overall, compared with VKAs use, the use of NOACs was associated with reduced risks of ischemic stroke (RR 0.49, 95% CI 0.34-0.69), all-cause death (RR 0.44, 95% CI 0.35-0.55), and intracranial hemorrhage (RR 0.43, 95% CI 0.24-0.77). There were no differences in the risks of stroke or systemic embolism, major or clinically relevant bleeding, and gastrointestinal bleeding in patients with NOACs versus VKAs. Re-analyses with a fixed-effects model produced the similar results as the main analyses. For the efficacy and safety outcomes, comparisons of NOACs versus warfarin produced the similar results as those of NOACs versus VKAs. Based on current data from observational studies, compared with VKAs, NOACs had similar or lower risks of thromboembolic and bleeding events in patients with HCM and AF.

How Did We Get Here?: A Historical Review and Critical Analysis of Anticoagulation Therapy Following Mechanical Valve Replacement

Managing severe valvular heart disease with mechanical valve replacement necessitates lifelong anticoagulation with a vitamin K antagonist. Optimal anticoagulation intensity for patients with mechanical valves remains uncertain; current recommendations are inconsistent across guideline bodies and largely based on expert opinion. In this review, we outline the history of anticoagulation therapy in patients with mechanical heart valves and critically evaluate current antithrombotic guidelines for these patients. We conclude that randomized trials evaluating optimal anticoagulation intensity in patients with mechanical valves are needed, and that future guidelines must better justify antithrombotic treatment recommendations.

Outcome reporting from clinical trials of non-valvular atrial fibrillation treated with traditional Chinese medicine or Western medicine: a systematic review

OBJECTIVES

To examine variation in outcomes, outcome measurement instruments (OMIs) and measurement times in clinical trials of non-valvular atrial fibrillation (NVAF) and to identify outcomes for prioritisation in developing a core outcome set (COS) in this field.

DESIGN

This study was a systematic review.

DATA SOURCES

Clinical trials published between January 2015 and March 2019 were obtained from PubMed, the Cochrane Library, Web of Science, Wanfang Database, the China National Knowledge Infrastructure and SinoMed.

ELIGIBILITY CRITERIA

Randomised controlled trials (RCTs) and observational studies were considered. Interventions included traditional Chinese medicine and Western medicine. The required treatment duration or follow-up time was ≥4 weeks. The required sample size was ≥30 and≥50 in each group in RCTs and observational studies, respectively. We excluded trials that aimed to investigate the outcome of complications of NVAF, to assess the mechanisms or pharmacokinetics, or for which full text could not be acquired.

DATA EXTRACTION AND SYNTHESIS

The general information and outcomes, OMIs and measurement times were extracted. The methodological and outcome reporting quality were assessed. The results were analysed by descriptive analysis.

RESULTS

A total of 218 articles were included from 25 255 articles. For clinical trials of antiarrhythmic therapy, 69 outcomes from 16 outcome domains were reported, and 28 (31.82%, 28/88) outcomes were reported only once; the most frequently reported outcome was ultrasonic cardiogram. Thirty-one outcomes (44.93%, 31/69) were provided definitions or OMIs; the outcome measurement times ranged from 1 to 20 with a median of 3. For clinical trials of anticoagulation therapy, 82 outcomes from 18 outcome domains were reported; 38 (29.23%, 38/130) outcomes were reported only once. The most frequently reported outcome was ischaemic stroke. Forty (48.78%, 40/82) outcomes were provided OMIs or definitions; and the outcome measurement times ranged from 1 to 27 with a median of 8.

CONCLUSION

Outcome reporting in NVAF is inconsistent. Thus, developing a COS that can be used in clinical trials is necessary.

Interventions for Preventing Thromboembolic Events in Patients With Atrial Fibrillation: A Systematic Review

BACKGROUND

The comparative safety and effectiveness of treatments to prevent thromboembolic complications in atrial fibrillation (AF) remain uncertain.

PURPOSE

To compare the effectiveness of medical and procedural therapies in preventing thromboembolic events and bleeding complications in adults with nonvalvular AF.

DATA SOURCES

English-language studies in several databases from 1 January 2000 to 14 February 2018.

STUDY SELECTION

Two reviewers independently screened citations to identify comparative studies of treatments to prevent stroke in adults with nonvalvular AF who reported thromboembolic or bleeding complications.

DATA EXTRACTION

Two reviewers independently abstracted data, assessed study quality and applicability, and rated strength of evidence.

DATA SYNTHESIS

Data from 220 articles were included. Dabigatran and apixaban were superior and rivaroxaban and edoxaban were similar to warfarin in preventing stroke or systemic embolism. Apixaban and edoxaban were superior and rivaroxaban and dabigatran were similar to warfarin in reducing the risk for major bleeding. Treatment effects with dabigatran were similar in patients with renal dysfunction (interaction P > 0.05), and patients younger than 75 years had lower bleeding rates with dabigatran (interaction P < 0.001). The benefit of treatment with apixaban was consistent in many subgroups, including those with renal impairment, diabetes, and prior stroke (interaction P > 0.05 for all). The greatest bleeding risk reduction was observed in patients with a glomerular filtration rate less than 50 mL/min/1.73 m2 (P = 0.003). Similar treatment effects were observed for rivaroxaban and edoxaban in patients with prior stroke, diabetes, or heart failure (interaction P > 0.05 for all).

LIMITATION

Heterogeneous study populations, interventions, and outcomes.

CONCLUSION

The available direct-acting oral anticoagulants (DOACs) are at least as effective and safe as warfarin for patients with nonvalvular AF. The DOACs had similar benefits across several patient subgroups and seemed safe and efficacious for a wide range of patients with nonvalvular AF.

PRIMARY FUNDING SOURCE

Patient-Centered Outcomes Research Institute. (PROSPERO: CRD42017069999).

Recent advances in the management of transient ischemic attacks

Significant advances in our understanding of transient ischemic attack (TIA) have taken place since it was first recognized as a major risk factor for stroke during the late 1950's. Recently, numerous studies have consistently shown that patients who have experienced a TIA constitute a heterogeneous population, with multiple causative factors as well as an average 5–10% risk of suffering a stroke during the 30 days that follow the index event. These two attributes have driven the most important changes in the management of TIA patients over the last decade, with particular attention paid to effective stroke risk stratification, efficient and comprehensive diagnostic assessment, and a sound therapeutic approach, destined to reduce the risk of subsequent ischemic stroke. This review is an outline of these changes, including a discussion of their advantages and disadvantages, and references to how new trends are likely to influence the future care of these patients.

Atrial Fibrillation and Anticoagulation in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) represents a common inherited cardiac disorder with well-known complications Including stroke and sudden cardiac death. There is a recognised association between HCM and the development of AF. This review describes the epidemiology of AF within the HCM population and analyses the risk factors for the development of AF. It further discusses the outcomes associated with AF in this population, including the evidence in support of higher stroke risk in patients with HCM with AF compared with the general AF population. Finally, the evidence and recommendations for anticoagulation in this patient group are addressed.