Reporting quality of randomized controlled trials evaluating non-vitamin K oral anticoagulants in atrial fibrillation: a systematic review

BACKGROUND

Randomized controlled trials (RCTs) are subject to bias if they lack methodological quality. Furthermore, optimal and transparent reporting of RCT findings aids their critical appraisal and interpretation. This study aimed to comprehensively evaluate the report quality of RCTs of non-vitamin K oral anticoagulants (NOACs) for the treatment of atrial fibrillation (AF) and to analyze the factors influencing the quality.

METHODS

By searching PubMed, Embase, Web of Science, and Cochrane Library databases RCTs published from inception to 2022 evaluating the efficacy of NOACs on AF were collected. By using the 2010 Consolidated Standards for Reporting Tests (CONSORT) statement, the overall quality of each report was assessed.

RESULTS

Sixty-two RCTs were retrieved in this study. The median of overall quality score in 2010 was 14 (range: 8.5-20). The extent of compliance with the Consolidated Standards of Reporting Trials reporting guideline differed substantially across items: 9 items were reported adequately (more than 90%), and 3 were reported adequately in less than 10% of trials. Multivariate linear regression analysis showed that the higher reporting scores were associated with higher journal impact factor (P = 0.01), international collaboration (P < 0.01), and Sources of trial funding (P = 0.02).

CONCLUSIONS

Although a large number of randomized controlled trials of NOACs for the treatment of AF were published after the CONSORT statement in 2010, the overall quality is still not satisfactory, thus weakening their potential utility and may mislead clinical decisions. This survey provides the first hint for researchers conducting trials of NOACs for AF to improve the quality of reports and to actively apply the CONSORT statement.

Direct Oral Anticoagulants Versus Vitamin K Antagonists for the Treatment of Left Ventricular Thrombus: An Updated Meta-Analysis of Cohort Studies and Randomized Controlled Trials

ABSTRACT

Left ventricular thrombi (LVTs) increase the risk of stroke, systemic embolism, and subsequent death. Current guidelines recommend vitamin K antagonists (VKAs) as first-line treatment for LVT. Direct oral anticoagulants (DOACs) are increasingly used as alternatives to warfarin for the treatment of LVT. However, the efficacy and safety of DOACs versus VKAs remain controversial. Thus, we conducted an updated meta-analysis of DOACs versus VKAs for LVT treatment. We systematically searched PubMed, Embase, ClinicalTrials, and Cochrane Library databases for relevant articles published before December 11, 2021. The relative risks (RRs) with 95% confidence intervals (CIs) were calculated for each study. The meta-analysis included 12 cohort studies and 3 randomized controlled trials with a total of 2334 patients. We found that DOACs had a lower risk of clinically significant bleeding than VKAs (RR = 0.6; 95% CI, 0.39 to 0.90; P = 0.01; I2 = 0%). There was no difference in LVT resolution (RR = 1.01; 95% CI, 0.93 to 1.09; P = 0.48; I2 = 0%), stroke and/or systematic embolic events (RR = 0.87; 95% CI, 0.11 to 1.55; P = 0.2; I2 = 30%), and all-cause mortality (RR = 0.9; 95% CI, 0.58 to 1.4; P = 0.65; I2 = 0%). Overall, DOACs are noninferior to warfarin in LVT treatment but have a lower risk of clinically significant bleeding. This suggests that DOACs might be better alternatives to warfarin for LVT treatment.

Non-vitamin K antagonist oral anticoagulants in patients with valvular heart disease

The non-vitamin K antagonist oral anticoagulants (NOACs) dabigatran, rivaroxaban, apixaban, and edoxaban have transformed the management of atrial fibrillation (AF), but are only approved by regulatory authorities for stroke prophylaxis in patients with so-called "non-valvular AF." This terminology has spawned confusion about which patients with valvular heart disease benefit from NOACs and which should be treated with vitamin K antagonists (VKAs) instead. Patients with valvular heart disease other than mechanical prosthetic valves or severe mitral stenosis (including those with bioprosthetic valves) were included in pivotal trials demonstrating the benefit of NOACs over VKAs, and consensus guidelines recommend NOACs over VKAs in these patients. Subsequent devoted randomized controlled trials in patients with AF and bioprosthetic valves, including transcatheter valves, have confirmed the safety of NOACs in this population. In patients with rheumatic mitral stenosis, observational studies indicate that NOACs may be safe and effective, but randomized controlled trials are ongoing. By contrast, a randomized controlled trial showed that dabigatran is harmful in patients with mechanical prosthetic mitral valves; however, these data may not extrapolate to patients with mechanical valve prostheses in other locations or to other NOACs, and randomized controlled trials are ongoing. In this review, we discuss these data in greater depth, and make recommendations for the use of NOACs in patients with valvular heart disease.

A post-hoc interpretable ensemble model to feature effect analysis in warfarin dose prediction for Chinese patients

To interprete the importance of clinical features and genotypes for warfarin daily dose prediction, we developed a post-hoc interpretable framework based on an ensemble predictive model. This framework includes permutation importance for global interpretation and local interpretable model-agnostic explanation (LIME) and shapley additive explanations (SHAP) for local explanation. The permutation importance globally ranks the importance of features on the whole data set. This can guide us to build a predictive model with less variables and the complexity of final predictive model can be reduced. LIME and SHAP together explain how the predictive model give the predicted dosage for specific samples. This help clinicians prescribe accurate doses to patients using more effective clinical variables. Results showed that both the permutation importance and SHAP demonstrated that VKORC1, age, serum creatinine (SCr), left atrium (LA) size, CYP2C9 and weight were the most important features on the whole data set. In specific samples, both SHAP and LIME discovered that in Chinese patients, wild-type VKORC1-AA, mutant-type CYP2C9*3, age over 60, abnormal LA size, SCr within the normal range, and using amiodarone definitely required dosage reduction, whereas mutant-type VKORC1-AG/GG, small age, SCr out of normal range, normal LA size, diabetes and heavy weight required dosage enhancement.

A novel vitamin K derived anticoagulant tolerant to genetic variations of vitamin K epoxide reductase

BACKGROUND

Vitamin K antagonists (VKAs), such as warfarin, have remained the cornerstone of oral anticoagulation therapy in the prevention and treatment of thromboembolism for more than half a century. They function by impairing the biosynthesis of vitamin K-dependent (VKD) clotting factors through the inhibition of vitamin K epoxide reductase (VKOR). The challenge of VKAs therapy is their narrow therapeutic index and highly variable dosing requirements, which are partially the result of genetic variations of VKOR.

OBJECTIVES

The goal of this study was to search for an improved VKA that is tolerant to the genetic variations of its target enzyme.

METHODS

A series of vitamin K derivatives with benzyl and related side-chain substitutions at the 3-position of 1,4-naphthoquinone were synthesized. The role of these compounds in VKD carboxylation was evaluated by mammalian cell-based assays and conventional in vitro activity assays.

RESULTS

Our results showed that replacing the phytyl side-chain with a methylene cyclooctatetraene (COT) moiety at the 3-position of vitamin K1 converted it from a substrate to an inhibitor for VKD carboxylation. Strikingly, this COT-vitamin K derivative displayed a similar inhibition potency in warfarin-resistant VKOR mutations whose warfarin resistance varied more than 400-fold. Further characterization of COT-vitamin K for the inhibition of VKD carboxylation suggested that this compound targets multiple enzymes in the vitamin K redox cycle. Importantly, the anticoagulation effect of COT-vitamin K can be rescued with high doses of vitamin K1 .

CONCLUSION

We discovered a vitamin K analogue that functions as a VKA and is tolerant to genetic variations in the target enzyme.

Impact of an oral anticoagulation self-monitoring and self-management program in patients with mechanical heart valve prosthesis

Objective: To analyze impact of implementation of an oral anticoagulation self-monitoring and self-management program among patients with mechanical valve prosthesis. Materials & methods: Observational and retrospective study performed in Hospital Moises Broggi, Barcelona, Spain. The program started on June 2019. The study compared 6-month period before and after the implementation of the program. Results: The study included 44 patients. There was a numerical increase of time in therapeutic range from 53.6 ± 21.3% to 57.1 ± 15.7% (p = 0.30). Proportion of patients with international normalized ratio (INR) >5 significantly decreased from 3.9 to 2.0% (p = 0.04). No significant differences were observed in thromboembolic or bleeding complications. Visits to emergency department decreased from (29.5 to 22.7%; p = 0.41). Conclusion: Oral anticoagulation self-monitoring and self-management program seems an appropriate approach that could provide additional benefits in selected patients with mechanical valve prosthesis.

The Hospital-Community-Family-Based Telemedicine (HCFT-AF) Program for Integrative Management of Patients With Atrial Fibrillation: Pilot Feasibility Study

Background

The potential effectiveness of integrated management in further improving the prognosis of patients with atrial fibrillation has been demonstrated; however, the best strategy for implementation remains to be discovered.

Objective

The aim of this study was to ascertain the feasibility of implementing integrated atrial fibrillation care via the Hospital-Community-Family–Based Telemedicine (HCFT-AF) program.

Methods

In this single-arm, pre-post design pilot study, a multidisciplinary teamwork, supported by efficient infrastructures, provided patients with integrated atrial fibrillation care following the Atrial fibrillation Better Care (ABC) pathway. Eligible patients were continuously recruited and followed up for at least 4 months. The patients’ drug adherence, and atrial fibrillation–relevant lifestyles and behaviors were assessed at baseline and at 4 months. The acceptability, feasibility, and usability of the HCFT-AF technology devices and engagement with the HCFT-AF program were assessed at 4 months.

Results

A total of 73 patients (mean age, 68.42 years; 52% male) were enrolled in November 2019 with a median follow up of 132 days (IQR 125–138 days). The patients’ drug adherence significantly improved after the 4-month intervention (P<.001). The vast majority (94%, 64/68) of indicated patients received anticoagulant therapy at 4 months, and none of them received antiplatelet therapy unless there was an additional indication. The atrial fibrillation–relevant lifestyles and behaviors ameliorated to varying degrees at the end of the study. In general, the majority of patients provided good feedback on the HCFT-AF intervention. More than three-quarters (76%, 54/71) of patients used the software or website more than once a week and accomplished clinic visits as scheduled.

Conclusions

The atrial fibrillation–integrated care model described in this study is associated with improved drug adherence, standardized therapy rate, and lifestyles of patients, which highlights the possibility to better deliver integrated atrial fibrillation management.

Trial Registration

Clinicaltrials.gov NCT04127799; https://clinicaltrials.gov/ct2/show/NCT04127799

Spontaneous rupture and hematoma of the sartorius muscle secondary to rivaroxaban therapy

Spontaneous muscular hematomas are quite rare as they occur mush less frequently than intracranial hematomas and gastrointestinal bleeding in patients under oral anticoagulant therapy. Coumarins, such as warfarin or acitrom, are the most widely prescribed oral anticoagulants agents and have been associated more with the development of hematomas than direct factor X inhibitors, such as rivaroxaban [ 1]. Few reports have linked oral anticoagulation therapy with the development of muscular hematomas; however, clinical cases regarding the involvement of the sartorius muscle remain limited. Patients with advanced age, under oral anticoagulant therapy with pain and ecchymosis in the thigh region, should undergo radiological evaluation utilizing ultrasonography, computed tomography or magnetic resonance imaging to establish an accurate diagnosis. The following case consists of a patient that while resting presented with a spontaneous rupture and hematoma of the sartorius muscle secondary to rivaroxaban use. During follow-up, the patient recovered completely.