Direct Oral Anticoagulants Versus Vitamin K Antagonists in Patients Undergoing Cardioversion for Atrial Fibrillation: a Systematic Review and Meta-analysis

Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice in a timely and comprehensive manner, the Chinese Society of Cardiology of the Chinese Medical Association and the Heart Rhythm Committee of the Chinese Society of Biomedical Engineering have jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines have comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2-VASc-60 stroke risk score based on the characteristics of AF in the Asian population. The guidelines have also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

A synthesis of pathways linking diet, metabolic risk and cardiovascular disease: a framework to guide further research and approaches to evidence-based practice

Cardiovascular disease (CVD) is the most common non-communicable disease occurring globally. Although previous literature has provided useful insights into the important role that diet plays in CVD prevention and treatment, understanding the causal role of diets is a difficult task considering inherent and introduced weaknesses of observational (e.g. not properly addressing confounders and mediators) and experimental research designs (e.g. not appropriate or well designed). In this narrative review, we organised current evidence linking diet, as well as conventional and emerging physiological risk factors, with CVD risk, incidence and mortality in a series of diagrams. The diagrams presented can aid causal inference studies as they provide a visual representation of the types of studies underlying the associations between potential risk markers/factors for CVD. This may facilitate the selection of variables to be considered and the creation of analytical models. Evidence depicted in the diagrams was systematically collected from studies included in the British Nutrition Task Force report on diet and CVD and database searches, including Medline and Embase. Although several markers and disorders linked to conventional and emerging risk factors for CVD were identified, the causal link between many remains unknown. There is a need to address the multifactorial nature of CVD and the complex interplay between conventional and emerging risk factors with natural and built environments, while bringing the life course into the spotlight.

Safety and efficacy of direct oral anticoagulants versus vitamin K antagonists in atrial fibrillation electrical cardioversion: An update systematic review and meta-analysis

BACKGROUND

A systematic evaluation focused on efficacy and safety for electrical cardioversion of atrial fibrillation (AF) among different Direct Oral Anticoagulants (DOACs) has not been previously performed. In this setting, we conducted a meta-analysis of studies evaluating DOACs vs vitamin K antagonists (VKA) as common comparator.

METHODS

We searched Cochrane Library, Pubmed, Web Of Science and Scopus databases for all English-only articles concerning studies that have estimated the effect of DOACs and VKA on stroke, transient ischemic attack or systemic embolism (SSE) and major bleeding (MB) events in AF patients undergoing electrical cardioversion. We selected 22 articles comprising 66 cohorts and 24,322 procedures (12,612 with VKA).

RESULTS

During follow-up (studies' median 42 days), 135 SSE (52 DOACs and 83 VKA) and 165 MB (60 DOACs and 105 VKA) were recorded. The overall pooled effects, DOACs vs VKA, was estimated by an univariate Odds Ratio of 0.92 (0.63-1.33; p = 0.645) for SSE and 0.58 (0.41-0.82; p = 0.002) for MB; at bivariate evaluation, adjusting for study type, were respectively 0.94 (0.55-1.63; p = 0.834) and 0.63 (0.43-0.92, p = 0.016). Each single DOAC showed similar and non statistically different results in outcome occurrence compared to VKA as well as when Apixaban, Dabigatran, Edoxaban and Rivaroxaban were indirectly compared to each other.

CONCLUSIONS

In patients undergoing electrical cardioversion, compared to VKA, DOACs have similar thromboembolic protection with lower major bleeding incidence. Single molecule does not show difference in event rate compared to each other. Our findings, provide useful information about safety and efficacy profile of DOACs and VKA.

The association of non-vitamin K antagonist oral anticoagulants vs. warfarin and the risk of fractures for patients with atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

The fracture risks of non-vitamin K antagonist oral anticoagulants (NOACs) vs. warfarin in patients with atrial fibrillation (AF) remain controversial.

METHODS

PubMed, Cochrane Library, EMBASE, Clinical Trials.gov databases for RCTs, and cohort studies were systematically searched from inception to 10 June 2021.

RESULTS

Twelve-two studies met the inclusion criteria and 477,821 patients were included. Warfarin increased the risk of fracture in AF patients compared with NOACs in overall any fracture (RR = 0.79; 95% CI = 0.70-10.88; p = 0.00), osteoporotic fracture (RR = 0.746; 95% CI = 0.630-0.883; p = 0.001). No significant difference was observed in the hip or pelvic fracture, vertebral fracture, extremity fracture, wrist fracture, femoral neck fracture, and ankle fracture. In subgroup analyses based on several aspects, NOACs were associated with a significant reduction in any fracture (standard dosage NOACs, cohort studies, elderly patients, rivaroxaban in RCTs, dabigatran, rivaroxaban, and apixaban in cohort studies), in the hip/pelvic fracture (follow-up time ≤1 year, cohort studies), and osteoporotic fracture (cohort studies).

CONCLUSION

NOACs were associated with a significantly lower risk of any fracture and osteoporotic fracture compared to warfarin. This benefit was also observed in specific NOACs types of dabigatran, rivaroxaban, and apixaban. However, whether NOACs had a less fracture risk than warfarin on the other risk of fractures was still uncertain.

Retrograde autologous priming in cardiac surgery: a systematic review and meta-analysis

OBJECTIVES

Guidelines recommend retrograde autologous priming (RAP) of the cardiopulmonary bypass circuit. However, the efficacy and safety of RAP is not well-established. We performed a systematic review and meta-analysis to determine the effects of RAP on transfusion requirements, morbidity and mortality.

METHODS

We searched Cochrane Central Register of Controlled Trials, Medline, ScienceDirect, Cumulative Index to Nursing and Allied Health Literature and Embase for randomized controlled trials (RCTs) and observational studies comparing RAP to no-RAP. We performed title and abstract review, full-text screening, data extraction and risk of bias assessment independently and in duplicate. We pooled data using a random effects model.

RESULTS

Twelve RCTs (n = 1206) and 17 observational studies (n = 3565) were included. Fewer patients required blood transfusions with RAP [RCTs; risk ratio 0.58 [95% confidence interval (CI): 0.51, 0.65], P < 0.001, and observational studies; risk ratio 0.65 [95% CI: 0.53, 0.80], P < 0.001]. The number of units transfused per patient was also lower among patients who underwent RAP (RCTs; mean difference -0.38 unit [95% CI: -0.72, -0.04], P = 0.03, and observational studies; mean difference -1.03 unit [95% CI: -1.76, -0.29], P < 0.006).

CONCLUSIONS

This meta-analysis supports the use of RAP as a blood conservation strategy since its use during cardiopulmonary bypass appears to reduce transfusion requirements.

Thromboembolic events following cardioversion of acute atrial fibrillation and flutter: a systematic review and meta-analysis

BACKGROUND

Recent studies have presented concerning data on the safety of cardioversion for acute atrial fibrillation and flutter. We conducted this meta-analysis to evaluate the effect of oral anticoagulation use on thromboembolic events post-cardioversion of low-risk acute atrial fibrillation and flutter patients of < 48 h in duration.

METHODS

We searched MEDLINE, Embase, and Cochrane from inception through February 6, 2020 for studies reporting thromboembolic events post-cardioversion of acute atrial fibrillation and flutter. Main outcome was thromboembolic events within 30 days post-cardioversion. Primary analysis compared thromboembolic events based on oral anticoagulation use versus no oral anticoagulation use. Secondary analysis was based on baseline thromboembolic risk. We performed meta-analyses where 2 or more studies were available, by applying the DerSimonian-Laird random-effects model. Risk of bias was assessed with the Quality in Prognostic Studies tool.

RESULTS

Of 717 titles screened, 20 studies met inclusion criteria. Primary analysis of seven studies with low risk of bias demonstrated insufficient evidence regarding the risk of thromboembolic events associated with oral anticoagulation use (RR = 0.82 where RR < 1 suggests decreased risk with oral anticoagulation use; 95% CI 0.27 to 2.47; I² = 0%). Secondary analysis of 13 studies revealed increased risk of thromboembolic events with high baseline thromboembolic risk (RR = 2.25 where RR > 1 indicates increased risk with higher CHADS₂ or CHA₂DS₂-VASc scores; 95% CI 1.25 to 4.04; I² = 0%).

CONCLUSION

Primary analysis revealed insufficient evidence regarding the effect of oral anticoagulation use on thromboembolic events post-cardioversion of low-risk acute atrial fibrillation and flutter, though the event rate is low in contemporary practice. Our findings can better inform patient-centered decision-making when considering 4-week oral anticoagulation use for acute atrial fibrillation and flutter patients.

Unmet Clinical Needs in Elderly Patients Receiving Direct Oral Anticoagulants for Stroke Prevention in Non-valvular Atrial Fibrillation

Vitamin K antagonists have been used for many years as the treatment of choice for long-term oral anticoagulation in patients with non-valvular atrial fibrillation. Unfortunately, the use of those drugs in the real-world setting, particularly among elderly patients, is suboptimal because of their limitations in management. Therefore, many patients were not adequately anticoagulated. Direct oral anticoagulants have been demonstrated to overcome almost all the limitations derived from the use of vitamin K antagonists. Direct oral anticoagulants are at least as effective as vitamin K antagonists in preventing thromboembolic events in patients with non-valvular atrial fibrillation and safer in reducing the risk of intracranial haemorrhage and all-cause mortality. However, as a result of the strict inclusion and exclusion criteria applied to patients, data coming from randomized controlled trials might not apply to the general population. Furthermore, elderly patients were scarcely represented in randomized controlled trials with direct oral anticoagulants. Therefore in elderly patients with non-valvular atrial fibrillation, unmet clinical needs still exist. This review article highlights some of them and provides potential answers based on the results coming from randomized clinical trials, real-world data, and the authors' clinical experience.

Intravenous iron therapy for patients with preoperative iron deficiency or anaemia undergoing cardiac surgery reduces blood transfusions: a systematic review and meta-analysis

OBJECTIVES

The benefits of preoperative intravenous (IV) iron treatment in cardiac surgery patients with preoperative anaemia or iron deficiency have not been well-established. We performed a systematic review and meta-analysis to determine the effects of treating preoperative anaemia or iron deficiency with IV iron in adult cardiac surgery patients.

METHODS

We searched Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval Systems Online and Excerpta Medica Database for randomized controlled trials (RCTs) and observational studies comparing IV iron to oral iron or no iron. We performed title and abstract, full-text screening, data extraction and risk of bias assessment independently and in duplicate. We pooled data using a random effects model and evaluated the overall quality of evidence.

RESULTS

We identified 4 RCTs and 7 observational studies. Pooled data from observational studies suggested a benefit of IV iron compared to no iron on mortality [relative risk 0.39, 95% confidence interval (CI) 0.23-0.65; P < 0.001, very low quality], units transfused per patient (mean difference -1.22, 95% CI -1.85 to -0.60; P < 0.001, very low quality), renal injury (relative risk 0.50, 95% CI 0.36-0.69; P < 0.001, very low quality) and hospital length of stay (mean difference -4.24 days, 95% CI -6.86 to -1.63; P = 0.001, very low quality). Pooled data from RCTs demonstrated a reduction in the number of patients transfused with IV iron compared to oral or no iron (relative risk 0.81, 95% CI 0.70-0.94; P = 0.005, moderate quality). The pooled estimates of effect from RCTs for mortality, hospital length of stay, units transfused per patient and renal injury were consistent in direction with observational studies.

CONCLUSIONS

This meta-analysis suggests that IV iron improves postoperative morbidity in adult cardiac surgery patients with preoperative anaemia or iron deficiency. A large, rigorous, placebo-controlled, double-blinded, multicentre trial is needed to clarify the role of IV iron in this patient population.

CLINICAL TRIAL REGISTRATION

International prospective register of systematic reviews ID Number CRD42019122844.

The 2020 Canadian Cardiovascular Society/Canadian Heart Rhythm Society Comprehensive Guidelines for the Management of Atrial Fibrillation

The Canadian Cardiovascular Society (CCS) atrial fibrillation (AF) guidelines program was developed to aid clinicians in the management of these complex patients, as well as to provide direction to policy makers and health care systems regarding related issues. The most recent comprehensive CCS AF guidelines update was published in 2010. Since then, periodic updates were published dealing with rapidly changing areas. However, since 2010 a large number of developments had accumulated in a wide range of areas, motivating the committee to complete a thorough guideline review. The 2020 iteration of the CCS AF guidelines represents a comprehensive renewal that integrates, updates, and replaces the past decade of guidelines, recommendations, and practical tips. It is intended to be used by practicing clinicians across all disciplines who care for patients with AF. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system was used to evaluate recommendation strength and the quality of evidence. Areas of focus include: AF classification and definitions, epidemiology, pathophysiology, clinical evaluation, screening and opportunistic AF detection, detection and management of modifiable risk factors, integrated approach to AF management, stroke prevention, arrhythmia management, sex differences, and AF in special populations. Extensive use is made of tables and figures to synthesize important material and present key concepts. This document should be an important aid for knowledge translation and a tool to help improve clinical management of this important and challenging arrhythmia.