Perioperative Heparin Bridging in Atrial Fibrillation Patients Requiring Temporary Interruption of Anticoagulation: Evidence from Meta-analysis

Treatment Effects in Randomized and Nonrandomized Studies of Pharmacological Interventions: A Meta-Analysis

Importance

Randomized clinical trials (RCTs) are widely regarded as the methodological benchmark for assessing clinical efficacy and safety of health interventions. There is growing interest in using nonrandomized studies to assess efficacy and safety of new drugs.

Objective

To determine how treatment effects for the same drug compare when evaluated in nonrandomized vs randomized studies.

Data Sources

Meta-analyses published between 2009 and 2018 were identified in MEDLINE via PubMed and the Cochrane Database of Systematic Reviews. Data analysis was conducted from October 2019 to July 2024.

Study Selection

Meta-analyses of pharmacological interventions were eligible for inclusion if both randomized and nonrandomized studies contributed to a single meta-analytic estimate.

Data Extraction and Synthesis

For this meta-analysis using a meta-epidemiological framework, separate summary effect size estimates were calculated for nonrandomized and randomized studies within each meta-analysis using a random-effects model and then these estimates were compared. The reporting of this study followed the Guidelines for Reporting Meta-Epidemiological Methodology Research and relevant portions of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline.

Main Outcome and Measures

The primary outcome was discrepancies in treatment effects obtained from nonrandomized and randomized studies, as measured by the proportion of meta-analyses where the 2 study types disagreed about the direction or magnitude of effect, disagreed beyond chance about the effect size estimate, and the summary ratio of odds ratios (ROR) obtained from nonrandomized vs randomized studies combined across all meta-analyses.

Results

A total of 346 meta-analyses with 2746 studies were included. Statistical conclusions about drug benefits and harms were different for 130 of 346 meta-analyses (37.6%) when focusing solely on either nonrandomized or randomized studies. Disagreements were beyond chance for 54 meta-analyses (15.6%). Across all meta-analyses, there was no strong evidence of consistent differences in treatment effects obtained from nonrandomized vs randomized studies (summary ROR, 0.95; 95% credible interval [CrI], 0.89-1.02). Compared with experimental nonrandomized studies, randomized studies produced on average a 19% smaller treatment effect (ROR, 0.81; 95% CrI, 0.68-0.97). There was increased heterogeneity in effect size estimates obtained from nonrandomized compared with randomized studies.

Conclusions and Relevance

In this meta-analysis of treatment effects of pharmacological interventions obtained from randomized and nonrandomized studies, there was no overall difference in effect size estimates between study types on average, but nonrandomized studies both overestimated and underestimated treatment effects observed in randomized studies and introduced additional uncertainty. These findings suggest that relying on nonrandomized studies as substitutes for RCTs may introduce additional uncertainty about the therapeutic effects of new drugs.

Perioperative stroke

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.

Prevalence of bleeding secondary to anticoagulation and mortality in patients with atrial fibrillation admitted with SARS-CoV-2 infection

INTRODUCTION AND PURPOSE

Atrial fibrillation (AF) is common in patients admitted with severe COVID-19. However, there is limited data about the management of chronic anticoagulation therapy in these patients. We assessed the anticoagulation and incidence of major cardiovascular events in hospitalized patients with AF and COVID-19.

METHODS

We retrospectively investigated all consecutive patients with AF admitted with COVID-19 between March and May 2020 in 9 Spanish hospitals. We selected a control group of non-AF patients consecutively admitted with COVID-19. We compared baseline characteristics, incidence of major bleeding, thrombotic events and mortality. We used propensity score matching (PSM) to minimize potential confounding variables, as well as a multivariate analysis to predict major bleeding and death.

RESULTS

305 patients admitted with AF and COVID-19 were included. After PSM, 151 AF patients were matched with 151 control group patients. During admission, low-molecular-weight heparin was the principal anticoagulant and the incidence of major bleeding and mortality were higher in the AF group [16 (10.6%) vs 3 (2%), p = 0.003; 52 (34.4%) vs 35 (23.2%), p = 0.03, respectively]. The multivariate analysis showed the presence of AF as independent predictor of in-hospital major bleeding and mortality in COVID-19 patients. In AF group, a secondary multivariate analysis identified high levels of D-dimer as independent predictor of in-hospital major bleeding.

CONCLUSIONS

AF patients admitted with COVID-19 represent a population at high risk for bleeding and mortality during admission. It seems advisable to individualize anticoagulation therapy during admission, considering patient specific bleeding and thrombotic risk.

Perioperative Considerations for Antithrombotic Therapy in Oculofacial Surgery: A Review of Current Evidence and Practice Guidelines

PURPOSE

Recent survey studies have demonstrated wide variability in practice patterns regarding the management of antithrombotic medications in oculofacial plastic surgery. Current evidence and consensus guidelines are reviewed to guide perioperative management of antithrombotic medications.

METHODS

Comprehensive literature review of PubMed database on perioperative use of antithrombotic medication.

RESULTS/CONCLUSIONS

Perioperative antithrombotic management is largely guided by retrospective studies, consensus recommendations, and trials in other surgical fields due to the limited number of studies in oculoplastic surgery. This review summarizes evidence-based recommendations from related medical specialties and provides context for surgeons to tailor antithrombotic medication management based on patient's individual risk. The decision to continue or cease antithrombotic medications prior to surgery requires a careful understanding of risk: risk of intraoperative or postoperative bleeding versus risk of a perioperative thromboembolic event. Cessation and resumption of antithrombotic medications after surgery should always be individualized based on the patient's thrombotic risk, surgical and postoperative risk of bleeding, and the particular drugs involved, in conjunction with the prescribing doctors. In general, we recommend that high thromboembolic risk patients undergoing high bleeding risk procedures (orbital or lacrimal surgery) may stop antiplatelet agents, direct oral anticoagulants, and warfarin including bridging warfarin with low-molecular weight heparin. Low-risk patients, regardless of type of procedure performed, may stop all agents. Decision on perioperative management of antithrombotic medications should be made in conjunction with patient's internist, cardiologist, hematologist, or other involved physicians which may limit the role of guidelines depending on patient risk and should be used on a case-by-case basis. Further studies are needed to provide oculofacial-specific evidence-based guidelines.

Prevalence of bleeding secondary to anticoagulation and mortality in patients with atrial fibrillation admitted with SARS-CoV-2 infection

Introduction and purpose

Atrial fibrillation (AF) is common in patients admitted with severe COVID-19. However, there is limited data about the management of chronic anticoagulation therapy in these patients. We assessed the anticoagulation and incidence of major cardiovascular events in hospitalized patients with AF and COVID-19.

Methods

We retrospectively investigated all consecutive patients with AF admitted with COVID-19 between March and May 2020 in 9 Spanish hospitals. We selected a control group of non-AF patients consecutively admitted with COVID-19. We compared baseline characteristics, incidence of major bleeding, thrombotic events and mortality. We used propensity score matching (PSM) to minimize potential confounding variables, as well as a multivariate analysis to predict major bleeding and death.

Results

305 patients admitted with AF and COVID-19 were included. After PSM, 151 AF patients were matched with 151 control group patients. During admission, low-molecular-weight heparin was the principal anticoagulant and the incidence of major bleeding and mortality were higher in the AF group [16 (10.6%) vs 3 (2%), p = 0.003; 52 (34.4%) vs 35 (23.2%), p = 0.03, respectively]. The multivariate analysis showed the presence of AF as independent predictor of in-hospital major bleeding and mortality in COVID-19 patients. In AF group, a secondary multivariate analysis identified high levels of D-dimer as independent predictor of in-hospital major bleeding.

Conclusions

AF patients admitted with COVID-19 represent a population at high risk for bleeding and mortality during admission. It seems advisable to individualize anticoagulation therapy during admission, considering patient specific bleeding and thrombotic risk.

Analysis of the ESC/EACTS 2020 Atrial Fibrillation Guidelines With Perioperative Implications

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide, with an individual lifetime risk of approximately 37% in the United States. Broadly defined as a supraventricular tachyarrhythmia with disorganized atrial activation, AF results in an increased risk of stroke, heart failure, valvular heart disease, and impaired quality of life, and confers a significant burden on the health of individuals and society. AF in the perioperative setting is common and a significant source of perioperative morbidity and mortality worldwide. The latest iteration of the European Society of Cardiology AF guidelines published in 2020 provide the clinician a valuable road map for the management of this arrythmia. This expert review will comprehensively analyze the 2020 European Society of Cardiology guidelines and provide perioperative management tools for the clinician.

Use of NOACS in high-risk patients with atrial fibrillation in Saudi Arabia: Perspectives on improving patient care

BACKGROUND

Despite the widespread and increasing use of NOACs in Saudi Arabia, there is a lack of contemporary guidance specific to the region. In particular, guidance on NOAC use in high-risk patients who are more likely to experience bleeding with oral anticoagulant therapy is needed. There is an unmet need for a review of contemporary evidence coupled with expert insights on safe and effective NOAC use in high-risk patients with AF in Saudi Arabia.

RESEARCH DESIGN AND METHODS

This article provides a detailed review of contemporary literature on NOAC use in high-risk patients with AF. Additionally, key gaps in the literature are identified and expert insights are shared to guide effective management of patients and the significance of local data is evaluated with respect to challenges in optimizing the use of NOACs.

CONCLUSIONS

This article provides information that complements and expands on existing reviews and guidelines on NOAC use in patients with AF, with a focus on challenges specific to the Saudi Arabian context with the potential to make a positive contribution to the medical community in Saudi Arabia and in other nations.

Predictors for blood loss and transfusion frequency to guide blood saving programs in primary knee- and hip-arthroplasty

Endoprosthetic surgery can lead to relevant blood loss resulting in red blood cell (RBC) transfusions. This study aimed to identify risk factors for blood loss and RBC transfusion that enable the prediction of an individualized transfusion probability to guide preoperative RBC provision and blood saving programs. A retrospective analysis of patients who underwent primary hip or knee arthroplasty was performed. Risk factors for blood loss and transfusions were identified and transfusion probabilities computed. The number needed to treat (NNT) of a potential correction of preoperative anemia with iron substitution for the prevention of RBC transfusion was calculated. A total of 308 patients were included, of whom 12 (3.9%) received RBC transfusions. Factors influencing the maximum hemoglobin drop were the use of drain, tranexamic acid, duration of surgery, anticoagulation, BMI, ASA status and mechanical heart valves. In multivariate analysis, the use of a drain, low preoperative Hb and mechanical heart valves were predictors for RBC transfusions. The transfusion probability of patients with a hemoglobin of 9.0–10.0 g/dL, 10.0–11.0 g/dL, 11.0–12.0 g/dL and 12.0–13.0 g/dL was 100%, 33.3%, 10% and 5.6%, and the NNT 1.5, 4.3, 22.7 and 17.3, while it was 100%, 50%, 25% and 14.3% with a NNT of 2.0, 4.0, 9.3 and 7.0 in patients with a drain, respectively. Preoperative anemia and the insertion of drains are more predictive for RBC transfusions than the use of tranexamic acid. Based on this, a personalized transfusion probability can be computed, that may help to identify patients who could benefit from blood saving programs.

The effect of heparin infusion intensity on outcomes for bridging hospitalized patients with atrial fibrillation

Background

Perioperative bridging in atrial fibrillation (AF) is associated with low thromboembolic rates but high bleeding rates. Recent guidance cautions the practice of bridging except in high risk patients. However, the practice of bridging varies widely and little data exist regarding appropriate anticoagulation intensity when using intravenous unfractionated heparin (UFH).

Hypothesis

To determine if high intensity UFH infusion regimens are associated with increased bleeding rates compared to low intensity regimens for bridging patients with AF.

Methods

We conducted a single center retrospective cohort study of admitted patients with non‐valvular AF receiving UFH for ≥24 hours. UFH intensities were chosen at the providers' discretion. The primary endpoint was the rate of bleeding defined by the International Society on Thrombosis and Hemostasis during UFH infusion or within 24 hours of discontinuation. The secondary endpoint was a composite of cardiovascular events, arterial thromboembolism, venous thromboembolism, myocardial infarctions and death during UFH infusion.

Results

A total of 497 patients were included in this analysis. Warfarin was used in 82.1% and direct acting oral anticoagulants in 14.1% of patients. The rate of any bleed was higher among high intensity compared to low intensity UFH regimens (10.5% vs 4.9%, odds ratio = 2.29, 95% confidence interval = 1.07‐4.90). Major bleeding was significantly higher among high intensity compared to low intensity UFH regimens. There was no difference in composite thrombotic events or death.

Conclusions

Low intensity UFH infusions, targeting lower anticoagulation targets, were associated with decreased bleeding rates without a signal of increased thromboembolic events in hospitalized AF patients.

Anesthesiologists Guide to the 2019 AHA/ACC/HRS Focused Update for the Management of Patients With Atrial Fibrillation

Perioperative physicians should be well versed in atrial fibrillation (AF) management because it is the most common sustained arrythmia in the United States. In this narrative review of the 2019 American Heart Association/American College of Cardiologists/Heart Rhythm Society Focused Update on Atrial Fibrillation, the authors detail the emergence of new evidence from completed studies that may affect the management of patients with AF presenting for surgery. Updates regarding non-vitamin K oral anticoagulants (NOACs) comprise the bulk of the update with newer evidence emerging regarding their equivalence and/or superiority compared to Coumadin. Apixaban is now the preferred drug of choice for first line stroke prevention in nonvalvular AF over Coumadin. Renal dysfunction and the management of patients with AF on hemodialysis is examined; in patients on hemodialysis with AF, the focused update recommends administration of either warfarin or dose-reduced apixaban. Evidence from new trials addressing the appropriate bridging of NOACs before surgery is discussed. Patients with nonvalvular AF may not exhibit an added benefit from bridging of anticoagulation, and perioperative physicians should balance the risks of stroke and major bleeding before surgery. Advances in nonpharmacologic treatment and management of AF are outlined, including left atrial appendage occlusion devices, catheter ablations, and electrical cardioversion. Anesthesiologists' understanding of these 2019 updated guidelines will allow for more adept optimization of patients with AF presenting for surgery.

Stroke and transient ischemic attacks related to antiplatelet or warfarin interruption

OBJECTIVE

Patients on anticoagulant or antiplatelet therapy are often required to discontinue these medications before and during surgical or invasive procedures. In some cases, the patient stops the treatment without medical supervision. These situations may increase stroke risk. To identify the ischemic stroke and transient ischemic attack (TIA) prevalence related to length of time of discontinuation of antiplatelet or vitamin K antagonist therapy, in a group of inpatients from a specialized neurological hospital in Brazil.

METHODS

Cross-sectional, retrospective and descriptive study of stroke inpatients for three years. Medical reports were reviewed to find study participants, stroke characteristics, risk factors, reasons and time of drug interruption.

RESULTS

In three years, there were 360 stroke and TIA inpatients, of whom 27 (7.5%) had a history of antiplatelet or vitamin K antagonist interruption correlated with the time of the event (81% ischemic stroke, 19% TIA). The median time between antiplatelet interruption and an ischemic event was five days, and 62% of events occurred within seven days after drug suspension. For vitamin K antagonists, the average time to the ischemic event was 10.4 days (SD = 5.7), and in 67% of patients, the time between drug discontinuation and the event was 7-14 days. The most frequent reason for drug suspension was patient negligence (37%), followed by planned surgery or invasive examination (26%) and side effects, including hemorrhage (18.5%).

CONCLUSION

Antiplatelet or vitamin K antagonist suspension has a temporal relationship with the occurrence of stroke and TIA. Since these events are preventable, it is crucial that healthcare professionals convince their patients that drug withdrawal can cause serious consequences.

Update in perioperative medicine: practice changing evidence published in 2016

This summary reviews 18 key articles published in 2016 which have significant practice implications for the perioperative medical care of surgical patients. Due to the multi-disciplinary nature of the practice of perioperative medicine, important new evidence is published in journals representing a variety of medical and surgical specialties. Keeping current with the evidence that drives best practice in perioperative medicine is therefore challenging. We set out to identify, critically review, and summarize key evidence which has the most potential for practice change. We integrated the new evidence into the existing body of medical knowledge and identified practical implications for real world patient care. The articles address issues related to anticoagulation, transfusion threshold, immunosuppressive medications, postoperative delirium, myocardial injury after noncardiac surgery, postoperative pain management, perioperative management of antihypertensives, perioperative fasting, and perioperative diabetic control.

Impact of antithrombotic treatment on clinical outcomes after craniotomy for unruptured intracranial aneurysm

OBJECTIVE

Patients receiving antithrombotic treatment occasionally undergo craniotomy. We aimed to explore the impact of perioperative use of antithrombotic agents on the occurrence of surgical complications and clinical outcomes in patients with unruptured intracranial aneurysm (UIA).

PATIENTS AND METHODS

We retrospectively analyzed 401 consecutive patients who had undergone craniotomy for UIA at our institution between January 2006 and December 2016. Patients were divided into two groups: those who received oral antiplatelet and/or anticoagulant agents during the perioperative period (antithrombotic treatment group, n=45); and those who did not (no antithrombotic treatment group, n=356). In the antithrombotic treatment group, 40 patients received antiplatelet alone, 2 received anticoagulant alone, and 3 received antiplatelet plus anticoagulant.

RESULTS

The two groups showed no significant differences in mortality, morbidity, or occurrence of symptomatic brain infarction, but intracranial hemorrhage was more frequent in the antithrombotic treatment group than in the no antithrombotic treatment group (p=0.0187). Multivariate analysis revealed posterior location of the aneurysm (odds ratio (OR), 8.10; 95% confidence interval (CI), 2.77-23.68; p=0.0001) and surgical procedure (OR, 5.48; 95%CI, 1.68-17.86; p=0.0048) as significantly correlated with severe morbidity, and intracranial hemorrhage as correlated significantly with antithrombotic treatment (OR, 3.83; 95%CI, 1.36-10.76; p=0.0110).

CONCLUSIONS

This study provides important information about the occurrence of intracranial hemorrhage and clinical outcomes in patients undergoing antithrombotic treatment during the perioperative period of craniotomy for UIA.

2017 consensus of the Asia Pacific Heart Rhythm Society on stroke prevention in atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia, causing a 2-fold increase in mortality and a 5-fold increase in stroke. The Asian population is rapidly aging, and in 2050, the estimated population with AF will reach 72 million, of whom 2.9 million may suffer from AF-associated stroke. Therefore, stroke prevention in AF is an urgent issue in Asia. Many innovative advances in the management of AF-associated stroke have emerged recently, including new scoring systems for predicting stroke and bleeding risks, the development of non-vitamin K antagonist oral anticoagulants (NOACs), knowledge of their special benefits in Asians, and new techniques. The Asia Pacific Heart Rhythm Society (APHRS) aimed to update the available information, and appointed the Practice Guideline sub-committee to write a consensus statement regarding stroke prevention in AF. The Practice Guidelines sub-committee members comprehensively reviewed updated information on stroke prevention in AF, emphasizing data on NOACs from the Asia Pacific region, and summarized them in this 2017 Consensus of the Asia Pacific Heart Rhythm Society on Stroke Prevention in AF. This consensus includes details of the updated recommendations, along with their background and rationale, focusing on data from the Asia Pacific region. We hope this consensus can be a practical tool for cardiologists, neurologists, geriatricians, and general practitioners in this region. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician׳s decision remains the most important factor in the management of AF.

Thromboembolic and major bleeding events in relation to perioperative bridging of vitamin K antagonists in 649 fast-track total hip and knee arthroplasties

Background - The benefit of preoperative bridging in surgical patients with continuous anticoagulant therapy is debatable, and drawing of meaningful conclusions may have been limited by mixed procedures with different thromboembolic and bleeding risks in most published studies. Patients and methods - This was an observational cohort treatment study in consecutive primary unilateral total hip and knee arthroplasty patients between January 2010 and November 2013 in 8 Danish fast-track departments. Data were collected prospectively on preoperative comorbidity and anticoagulants in patients with preoperative vitamin K antagonist (VKA) treatment. We performed 30-day follow-up on in-hospital complications and re-admissions through the Danish National Patient Registry and patient records. Results - Of 13,375 procedures, 649 (4.7%) were in VKA patients with a mean age of 73 (SD 9) years and a median length of stay of 3 days (IQR: 2-4). Preoperative bridging was used in 430 (67%), while 215 (33%) were paused. Of 4 arterial thromboembolic events (ATEs) (0.6%), 2 were in paused patients and 2 were in bridged patients (p = 0.6). Of 3 venous thromboembolic events (VTEs) (0.5%), 2 were in paused patients and 1 was in a bridged patient (p = 0.3). Of 8 major bleedings (MBs) (1.2%), 1 was in a paused patient and 7 were in bridged patients (p = 0.3), 5 of whom received therapeutic bridging. Similar results were found in a propensity-matched cohort. Interpretation - In contrast to recent studies in mixed surgical procedures, no statistically significant differences in ATE, VTE, or MB were found between preoperative bridging and pausation of VKA patients. However, the higher number of thromboembolic events in paused patients and the higher number of major bleedings in bridged patients warrant more extensive investigation.