Antithrombotic therapy in patients receiving saphenous vein coronary artery bypass grafts: a protocol for a systematic review and network meta-analysis.

INTRODUCTION: The current evidence for the prevention of saphenous vein graft failure (SVGF) after coronary artery bypass graft (CABG) surgery consists of direct head-to-head comparison of treatments (including placebo) in randomised-controlled trials (RCTs) and observational studies. However, summarising the evidence using traditional pairwise meta-analyses does not allow the inclusion of data from treatments that have not been compared head to head. Exclusion of such comparisons could impact the precision of pooled estimates in a meta-analysis. Hence, to address the challenge of whether aspirin alone or in addition to another antithrombotic agent is a more effective regimen to improve SVG patency, a network meta-analysis (NMA) is necessary. The objectives of this study are to synthesise the available evidence on antithrombotic agents (or their combination) and estimate the treatment effects among direct and indirect treatment comparisons on SVGF and major adverse cardiovascular events, and to generate a treatment ranking according to their efficacy and safety outcomes. METHODS: We will perform a systematic review of RCTs evaluating antithrombotic agents in patients undergoing CABG. A comprehensive English literature search will be conducted using electronic databases and grey literature resources to identify published and unpublished articles. Two individuals will independently and in duplicate screen potential studies, assess the eligibility of potential studies and extract data. Risk of bias and quality of evidence will also be evaluated independently and in duplicate. We will investigate the data to ensure its suitability for NMA, including adequacy of the outcome data and transitivity of treatment effects. We plan to estimate the pooled direct, indirect and the mixed effects for all antithrombotic agents using a NMA. ETHICS AND DISSEMINATION: Due to the nature of the study, there are no ethical concerns nor informed consent required. We anticipate that this NMA will be the first to simultaneously assess the relative effects of multiple antithrombotic agents in patients undergoing CABG. The results of this NMA will inform clinicians, patients and guideline developers the best available evidence on comparative effects benefits of antithrombotic agents after CABG while considering the side effect profile to support future clinical decision-making. We will disseminate the results of our systematic review and NMA through a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42017065678

Antithrombotic therapy in patients receiving saphenous vein coronary artery bypass grafts: a protocol for a systematic review and network meta-analysis.

INTRODUCTION: The current evidence for the prevention of saphenous vein graft failure (SVGF) after coronary artery bypass graft (CABG) surgery consists of direct head-to-head comparison of treatments (including placebo) in randomised-controlled trials (RCTs) and observational studies. However, summarising the evidence using traditional pairwise meta-analyses does not allow the inclusion of data from treatments that have not been compared head to head. Exclusion of such comparisons could impact the precision of pooled estimates in a meta-analysis. Hence, to address the challenge of whether aspirin alone or in addition to another antithrombotic agent is a more effective regimen to improve SVG patency, a network meta-analysis (NMA) is necessary. The objectives of this study are to synthesise the available evidence on antithrombotic agents (or their combination) and estimate the treatment effects among direct and indirect treatment comparisons on SVGF and major adverse cardiovascular events, and to generate a treatment ranking according to their efficacy and safety outcomes. METHODS: We will perform a systematic review of RCTs evaluating antithrombotic agents in patients undergoing CABG. A comprehensive English literature search will be conducted using electronic databases and grey literature resources to identify published and unpublished articles. Two individuals will independently and in duplicate screen potential studies, assess the eligibility of potential studies and extract data. Risk of bias and quality of evidence will also be evaluated independently and in duplicate. We will investigate the data to ensure its suitability for NMA, including adequacy of the outcome data and transitivity of treatment effects. We plan to estimate the pooled direct, indirect and the mixed effects for all antithrombotic agents using a NMA. ETHICS AND DISSEMINATION: Due to the nature of the study, there are no ethical concerns nor informed consent required. We anticipate that this NMA will be the first to simultaneously assess the relative effects of multiple antithrombotic agents in patients undergoing CABG. The results of this NMA will inform clinicians, patients and guideline developers the best available evidence on comparative effects benefits of antithrombotic agents after CABG while considering the side effect profile to support future clinical decision-making. We will disseminate the results of our systematic review and NMA through a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42017065678

External electrical and pharmacological cardioversion for atrial fibrillation, atrial flutter or atrial tachycardias: a network meta-analysis

Background: Atrial fibrillation (AF) is the most frequent sustained arrhythmia. Cardioversion is a rhythm control strategy to restore normal/sinus rhythm, and can be achieved through drugs (pharmacological) or a synchronised electric shock (electrical cardioversion). Objectives: To assess the efficacy and safety of pharmacological and electrical cardioversion for atrial fibrillation (AF), atrial flutter and atrial tachycardias. Search methods: We searched CENTRAL, MEDLINE, Embase, Conference Proceedings Citation Index-Science (CPCI-S) and three trials registers (ClinicalTrials.gov, WHO ICTRP and ISRCTN) on 14 February 2023. Selection criteria: We included randomised controlled trials (RCTs) at the individual patient level. Patient populations were aged ≥ 18 years with AF of any type and duration, atrial flutter or other sustained related atrial arrhythmias, not occurring as a result of reversible causes. Data collection and analysis: We used standard Cochrane methodology to collect data and performed a network meta-analysis using the standard frequentist graph-theoretical approach using the netmeta package in R. We used GRADE to assess the quality of the evidence which we presented in our summary of findings with a judgement on certainty. We calculated differences using risk ratios (RR) and 95% confidence intervals (CI) as well as ranking treatments using a P value. We assessed clinical and statistical heterogeneity and split the networks for the primary outcome and acute procedural success, due to concerns about violating the transitivity assumption. Main results: We included 112 RCTs (139 records), from which we pooled data from 15,968 patients. The average age ranged from 47 to 72 years and the proportion of male patients ranged from 38% to 92%. Seventy-nine trials were considered to be at high risk of bias for at least one domain, 32 had no high risk of bias domains, but had at least one domain classified as uncertain risk, and one study was considered at low risk for all domains. For paroxysmal AF (35 trials), when compared to placebo, anteroapical (AA)/anteroposterior (AP) biphasic truncated exponential waveform (BTE) cardioversion (RR: 2.42; 95% CI 1.65 to 3.56), quinidine (RR: 2.23; 95% CI 1.49 to 3.34), ibutilide (RR: 2.00; 95% CI 1.28 to 3.12), propafenone (RR: 1.98; 95% CI 1.67 to 2.34), amiodarone (RR: 1.69; 95% CI 1.42 to 2.02), sotalol (RR: 1.58; 95% CI 1.08 to 2.31) and procainamide (RR: 1.49; 95% CI 1.13 to 1.97) likely result in a large increase in maintenance of sinus rhythm until hospital discharge or end of study follow-up (certainty of evidence: moderate). The effect size was larger for AA/AP incremental and was progressively smaller for the subsequent interventions. Despite low certainty of evidence, antazoline may result in a large increase (RR: 28.60; 95% CI 1.77 to 461.30) in this outcome. Similarly, low-certainty evidence suggests a large increase in this outcome for flecainide (RR: 2.17; 95% CI 1.68 to 2.79), vernakalant (RR: 2.13; 95% CI 1.52 to 2.99), and magnesium (RR: 1.73; 95% CI 0.79 to 3.79). For persistent AF (26 trials), one network was created for electrical cardioversion and showed that, when compared to AP BTE incremental energy with patches, AP BTE maximum energy with patches (RR 1.35, 95% CI 1.17 to 1.55) likely results in a large increase, and active compression AP BTE incremental energy with patches (RR: 1.14, 95% CI 1.00 to 1.131) likely results in an increase in maintenance of sinus rhythm at hospital discharge or end of study follow-up (certainty of evidence: high). Use of AP BTE incremental with paddles (RR: 1.03, 95% CI 0.98 to 1.09; certainty of evidence: low) may lead to a slight increase, and AP MDS Incremental paddles (RR: 0.95, 95% CI 0.86 to 1.05; certainty of evidence: low) may lead to a slight decrease in efficacy. On the other hand, AP MDS incremental energy using patches (RR: 0.78, 95% CI 0.70 to 0.87), AA RBW incremental energy with patches (RR: 0.76, 95% CI 0.66 to 0.88), AP RBW incremental energy with patches (RR: 0.76, 95% CI 0.68 to 0.86), AA MDS incremental energy with patches (RR: 0.76, 95% CI 0.67 to 0.86) and AA MDS incremental energy with paddles (RR: 0.68, 95% CI 0.53 to 0.83) probably result in a decrease in this outcome when compared to AP BTE incremental energy with patches (certainty of evidence: moderate). The network for pharmacological cardioversion showed that bepridil (RR: 2.29, 95% CI 1.26 to 4.17) and quindine (RR: 1.53, (95% CI 1.01 to 2.32) probably result in a large increase in maintenance of sinus rhythm at hospital discharge or end of study follow-up when compared to amiodarone (certainty of evidence: moderate). Dofetilide (RR: 0.79, 95% CI 0.56 to 1.44), sotalol (RR: 0.89, 95% CI 0.67 to 1.18), propafenone (RR: 0.79, 95% CI 0.50 to 1.25) and pilsicainide (RR: 0.39, 95% CI 0.02 to 7.01) may result in a reduction in this outcome when compared to amiodarone, but the certainty of evidence is low. For atrial flutter (14 trials), a network could be created only for antiarrhythmic drugs. Using placebo as the common comparator, ibutilide (RR: 21.45, 95% CI 4.41 to 104.37), propafenone (RR: 7.15, 95% CI 1.27 to 40.10), dofetilide (RR: 6.43, 95% CI 1.38 to 29.91), and sotalol (RR: 6.39, 95% CI 1.03 to 39.78) probably result in a large increase in the maintenance of sinus rhythm at hospital discharge or end of study follow-up (certainty of evidence: moderate), and procainamide (RR: 4.29, 95% CI 0.63 to 29.03), flecainide (RR 3.57, 95% CI 0.24 to 52.30) and vernakalant (RR: 1.18, 95% CI 0.05 to 27.37) may result in a large increase in maintenance of sinus rhythm at hospital discharge or end of study follow-up (certainty of evidence: low). All tested electrical cardioversion strategies for atrial flutter had very high efficacy (97.9% to 100%). The rate of mortality (14 deaths) and stroke or systemic embolism (3 events) at 30 days was extremely low. Data on quality of life were scarce and of uncertain clinical significance. No information was available regarding heart failure readmissions. Data on duration of hospitalisation was scarce, of low quality, and could not be pooled. Authors' conclusions: Despite the low quality of evidence, this systematic review provides important information on electrical and pharmacological strategies to help patients and physicians deal with AF and atrial flutter. In the assessment of the patient comorbidity profile, antiarrhythmic drug onset of action and side effect profile versus the need for a physician with experience in sedation, or anaesthetics support for electrical cardioversion are key aspects when choosing the cardioversion method

External electrical and pharmacological cardioversion for atrial fibrillation, atrial flutter or atrial tachycardias:a network meta-analysis

BackgroundAtrial fibrillation (AF) is the most frequent sustained arrhythmia. Cardioversion is a rhythm control strategy torestore normal/sinus rhythm, and can be achieved through drugs (pharmacological) or a synchronized electricshock (electrical cardioversion).ObjectivesTo assess the efficacy and safety of pharmacological and electrical cardioversion for AF.Search methodsWe searched CENTRAL, MEDLINE, Embase, Conference Proceedings Citation Index-Science (CPCI-S) andthree trials registers (ClinicalTrials.gov, WHO ICTRP and ISRCTN) on 14 February 2023.Selection criteriaWe included randomised controlled trials (RCTs) at individual patient level. Patient populations were aged ≥18years with AF of any type and duration, atrial flutter or other sustained related atrial arrhythmias, not occurring asa result of reversible causes.Data collection and analysisWe used standard Cochrane methodology to collect data and performed a network meta-analysis using thestandard frequentist graph-theoretical approach using the netmeta package in R. We used GRADE to assess thequality of the evidence which we presented in in our summary of findings with a judgement on certainty. Wecalculated differences using risk ratios (RR) and 95% confidence intervals (CI) as well as ranking treatmentsusing a P-score. We assessed clinical and statistical heterogeneity and split the networks for the primaryoutcome and acute procedural success due to concerns about violating the transitivity assumption.Main resultsWe included 112 RCTs (139 records), from which we pooled data from 15,968 patients. Average age was 47 to72 years and proportion of male patients was 38%-92%.79 trials were considered high risk of bias for at least one domain, 32 had no high risk of bias domains, but hadat least one domain classified as uncertain risk, and one study was considered low risk for all domains.For paroxysmal AF (35 trials), when compared to Placebo, AA/AP BTE incremental cardioversion (RR: 2.42;95%CI 1.65 to 3.56), quinidine (RR: 2.23; 95%CI 1.49 to 3.34), ibutilide (RR: 2.00; 95%CI 1.28 to 3.12),propafenone (RR: 1.98; 95%CI 1.67 to 2.34), amiodarone (RR: 1.69; 95%CI 1.42 to 2.02), sotalol (RR: 1.58;95%CI 1.08 to 2.31) and procainamide (RR: 1.49; 95%CI 1.13 to 1.97) likely result in a large increase inmaintenance of sinus rhythm until hospital discharge or end of study follow-up (certainty of evidence: moderate).The effect size was larger for AA/AP incremental and was progressively smaller for the subsequent interventions.Despite low certainty of evidence Antazoline may result in a large increase (RR: 28.60; 95%CI 1.77 to 461.30) inthis outcome. Similarly, low certainty evidence suggests a large increase on this outcome for flecainide (RR: 2.17;95%CI 1.68 to 2.79), vernakalant (RR: 2.13; 95%CI 1.52 to 2.99), and magnesium (RR: 1.73; 95%CI 0.79 to 3.79)on this outcome.For persistent AF (26 trials), one network was created for electrical cardioversion and showed that whencompared to AP BTE incremental energy with patches, AP BTE maximum energy with patches (RR 1.35, 95%CI1.17 to 1.55) likely results in large increase and Active compression AP BTE incremental energy with patches(RR: 1.14, 95%CI 1.00 to 1.131) likely results in an increase in maintenance of sinus rhythm at hospital dischargeor end of study follow-up (certainty of evidence: high). Use of AP BTE incremental with paddles (RR: 1.03, 95%CI0.98 to 1.09; certainty of evidence: low) may lead to a little increase, and AP MDS Incremental paddles (RR: 0.95,95%CI 0.86 to 1.05; certainty of evidence: low) may lead to a little decrease in efficacy. On the other hand, APMDS incremental energy using patches (RR: 0.78, 95%CI 0.70 to 0.87), AA RBW incremental energy withpatches (RR: 0.76, 95%CI 0.66 to 0.88), AP RBW incremental energy with patches (RR: 0.76, 95%CI 0.68 to0.86), AA MDS incremental energy with patches (RR: 0.76, 95%CI 0.67 to 0.86) and AA MDS incremental energywith paddles (RR: 0.68, 95%CI 0.53 to 0.83) probably result in a decrease on this outcome when compared to APBTE incremental energy with patches (certainty of evidence: moderate). The network for pharmacologicalcardioversion showed that Bepridil (RR: 2.29, 95%CI 1.26 to 4.17) and Quindine (RR: 1.53, (95%CI 1.01 to 2.32)probably result in large increase in maintenance of sinus rhythm at hospital discharge or end of study follow-upwhen compared to amiodarone (certainty of evidence: moderate). Dofetilide (RR: 0.79, 95%CI 0.56 to 1.44),Sotalol (RR: 0.89, 95%CI 0.67 to 1.18), Propafenone (RR: 0.79, 95%CI 0.50 to 1.25) and Pilsicainide (RR: 0.39,95%CI 0.02 to 7.01) may result in a reduction of this outcome when compared to amiodarone, but certainty ofevidence is lowFor atrial flutter (14 trials) a network could be created only for antiarrhythmic drugs. Using Placebo as thecommon comparator, ibutilide (RR: 21.45, 95%CI 4.41 to 104.37), propafenone (RR: 7.15, 95%CI 1.27 to 40.10),dofetilide (RR: 6.43, 95%CI 1.38 to 29.91), and sotalol (RR: 6.39, 95%CI 1.03 to 39.78) probably result in a largeincrease in maintenance of sinus rhythm at hospital discharge or end of study follow-up (certainty of evidence:moderate), and procainamide (RR: 4.29, 95%CI 0.63 to 29.03), flecainide (RR 3.57, 95%CI 0.24 to 52.30) andvernakalant (RR: 1.18, 95%CI 0.05 to 27.37) may result in a large increase of maintenance of sinus rhythm athospital discharge or end of study follow-up at (certainty of evidence: low) All tested electrical cardioversionstrategies for atrial flutter had very high efficacy (97.9% to 100%).Mortality (14 deaths) and Stroke or systemic embolism (3 events) at 30 days was extremely low.Data on quality of life were scarce and of uncertain clinical significance. No information was available regardingheart failure readmissions. Data on duration of hospitalization was scarce, low quality, & could not be pooled.Authors' conclusionsDespite the low quality of evidence, this systematic review provides important information on electrical andpharmacological strategies to help patients and physicians deal with AF and atrial flutter.Assessing the patient comorbidity profile, antiarrhythmic drug onset of action & side effect profile vs. need for aphysician with experience in sedation, or anaesthetics support, for electrical cardioversion are key aspects whenchoosing the cardioversion method