Safety and efficacy of vernakalant for the conversion of atrial fibrillation to sinus rhythm; a phase 3b randomized controlled trial

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.

Efficacy and Safety of Intravenous Vernakalant in Rapid Cardioversion of Recent Onset Atrial Fibrillation: A Retrospective Single-Centre Study

BACKGROUND

We use vernakalant, an intravenous anti-arrhythmic, to cardiovert paroxysmal atrial fibrillation (AF) into sinus rhythm. It is a relatively atrium-selective, early-activating potassium and frequency-dependent sodium channel blocker with a half-life of 2 to 3 hours. Due to concerns regarding its safety profile, it is not Food and Drug Administration (FDA)-approved.

OBJECTIVE

This study aims to assess the efficacy of intravenous vernakalant in cardioversion of paroxysmal AF and the safety of its use.

METHODS

Patients with paroxysmal AF who presented to the American University of Beirut Medical Center (AUBMC) between 2015 and 2020 and received vernakalant for cardioversion were included. Patients did not receive vernakalant if they had any of the following: QTc > 440 ms, heart rate < 50 bpm, acute coronary syndrome within the last 30 days, second- and third-degree atrioventricular (AV) block in the absence of a pacemaker, severe aortic stenosis (AS), use of intravenous antiarrhythmics (class I and class III) within four hours of vernakalant infusion, systolic blood pressure <100 mmHg, and heart failure (New York Heart Association (NYHA) III or NYHA IV class). The primary endpoint is conversion to sinus rhythm for at least one minute within 90 minutes of the start of the vernakalant infusion. The secondary endpoint included the presence of these side effects: bradycardia, QTc prolongation, AV block, ventricular arrhythmias, hypotension, taste alteration/dysgeusia, sneezing, nausea, vomiting, paresthesia, cardiogenic shock, or death.

RESULTS

The study included 23 patients with paroxysmal AF (15 men, mean age 54 ± 14 years). Fourteen patients (61%) cardioverted to sinus rhythm within 90 minutes of the start of the Vernakalant infusion. Seven patients (30%) reverted to sinus rhythm within 15 minutes after the first infusion. After treatment with vernakalant, four patients (17%) developed sinus bradycardia, and four patients (17%) developed first-degree AV block. No patient had a QTc greater than 460 ms. None of the patients experienced sinus pauses, high-grade AV block, ventricular arrhythmias, hypotension, dysgeusia, sneezing, nausea, vomiting, paresthesia, cardiogenic shock, or death.

CONCLUSION

Vernakalant had 61% efficacy in the rapid cardioversion of paroxysmal AF to sinus rhythm, was well tolerated, and had a low rate of adverse events in our study population.

What determines the optimal pharmacological treatment of atrial fibrillation? Insights from in silico trials in 800 virtual atria

The best pharmacological treatment for each atrial fibrillation (AF) patient is unclear. We aim to exploit AF simulations in 800 virtual atria to identify key patient characteristics that guide the optimal selection of anti-arrhythmic drugs. The virtual cohort considered variability in electrophysiology and low voltage areas (LVA) and was developed and validated against experimental and clinical data from ionic currents to ECG. AF sustained in 494 (62%) atria, with large inward rectifier K+ current (IK1 ) and Na+ /K+ pump (INaK ) densities (IK1 0.11 ± 0.03 vs. 0.07 ± 0.03 S mF-1 ; INaK 0.68 ± 0.15 vs. 0.38 ± 26 S mF-1 ; sustained vs. un-sustained AF). In severely remodelled left atrium, with LVA extensions of more than 40% in the posterior wall, higher IK1 (median density 0.12 ± 0.02 S mF-1 ) was required for AF maintenance, and rotors localized in healthy right atrium. For lower LVA extensions, rotors could also anchor to LVA, in atria presenting short refractoriness (median L-type Ca2+ current, ICaL , density 0.08 ± 0.03 S mF-1 ). This atrial refractoriness, modulated by ICaL and fast Na+ current (INa ), determined pharmacological treatment success for both small and large LVA. Vernakalant was effective in atria presenting long refractoriness (median ICaL density 0.13 ± 0.05 S mF-1 ). For short refractoriness, atria with high INa (median density 8.92 ± 2.59 S mF-1 ) responded more favourably to amiodarone than flecainide, and the opposite was found in atria with low INa (median density 5.33 ± 1.41 S mF-1 ). In silico drug trials in 800 human atria identify inward currents as critical for optimal stratification of AF patient to pharmacological treatment and, together with the left atrial LVA extension, for accurately phenotyping AF dynamics. KEY POINTS: Atrial fibrillation (AF) maintenance is facilitated by small L-type Ca2+ current (ICaL ) and large inward rectifier K+ current (IK1 ) and Na+ /K+ pump. In severely remodelled left atrium, with low voltage areas (LVA) covering more than 40% of the posterior wall, sustained AF requires higher IK1 and rotors localize in healthy right atrium. For lower LVA extensions, rotors can also anchor to LVA, if the atria present short refractoriness (low ICaL ) Vernakalant is effective in atria presenting long refractoriness (high ICaL ). For short refractoriness, atria with fast Na+ current (INa ) up-regulation respond more favourably to amiodarone than flecainide, and the opposite is found in atria with low INa . The inward currents (ICaL and INa ) are critical for optimal stratification of AF patient to pharmacological treatment and, together with the left atrial LVA extension, for accurately phenotyping AF dynamics.

Bayesian Network Meta-analysis of Randomized Controlled Trials on the Efficacy of Antiarrhythmics in the Pharmacological Cardioversion of Paroxysmal Atrial Fibrillation

PURPOSE

Since atrial fibrillation (AF) is one of the major arrhythmias managed in hospitals worldwide, it has a major impact on public health. The guidelines agree on the desirability of cardioverting paroxysmal AF episodes. This meta-analysis aims to answer the question of which antiarrhythmic agent is most effective in cardioverting a paroxysmal AF.

MATERIALS AND METHODS

A systematic review and Bayesian network meta-analysis, searching MEDLINE, Embase, and CINAHL, were performed, including randomized controlled trials (RCTs) enrolling a population of unselected adult patients with a paroxysmal AF that compared at least two pharmacological regimes to restore the sinus rhythm or a cardioversion agent against a placebo. The main outcome was efficacy in restoring sinus rhythm.

RESULTS

Sixty-one RCTs (7988 patients) were included in the quantitative analysis [deviance information criterion (DIC) 272.57; I² = 3%]. Compared with the placebo, the association verapamil-quinidine shows the highest SUCRA rank score (87%), followed by antazoline (86%), vernakalant (85%), tedisamil at high dose (i.e., 0.6 mg/kg; 80%), amiodarone-ranolazine (80%), lidocaine (78%), dofetilide (77%), and intravenous flecainide (71%). Taking into account the degree of evidence of each individual comparison between pharmacological agents, we have drawn up a ranking of pharmacological agents from the most effective to the least effective.

CONCLUSIONS

In comparing the antiarrhythmic agents used to restore sinus rhythm in the case of paroxysmal AF, vernakalant, amiodarone-ranolazine, flecainide, and ibutilide are the most effective medications. The verapamil-quinidine combination seems promising, though few RCTs have studied it. The incidence of side effects must be taken into account in the choice of antiarrhythmic in clinical practice.

CLINICAL TRIAL REGISTRATION

PROSPERO: International prospective register of systematic reviews, 2022, CRD42022369433 (Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022369433 ).

Effectiveness and Safety Profiles of Vernakalant for Cardioversion of acute-onset Atrial Fibrillation: A Systematic Review and Meta-analysis

PURPOSE

Pharmacologic cardioversion is an effective clinical strategy for fibrillation. Vernakalant is a novel drug used to treat atrial fibrillation (AF). This study aimed to evaluate the efficacy- and tolerability-related data on vernakalant from clinical trials.

METHODS

Literature from PubMed and the Cochrane Library was systematically reviewed, and 139 eligible studies were found after specific key words were identified. Twelve randomized clinical trials discussing vernakalant cardioversion in patients with AF were chosen for the meta-analysis after scrutiny. Ten of the 12 trials used placebo while two reported data on active and established drugs to compare the effects of vernakalant. Three of the 12 trials included relevant clinical states in addition to AF.

FINDINGS

In this meta-analysis of data from 12 studies (2365 patients, 887 events), the rate of cardioversion from AF to sinus rhythm (SR) was significantly greater with vernakalant compared with placebo and active comparators (risk ratio = 5.60; 95% CI, 2.83-11.09; I² test for heterogeneity, 92%). Tolerability-related data revealed that dysgeusia, paresthesia, atrial flutter, and hypotension were major adverse events that occurred with vernakalant use, but the data were not clinically significant compared to placebo and active drug (risk ratio = 1.13; 95% CI, 0.86-1.47). Eleven deaths were reported in 4 trials, with vernakalant directly implicated in two deaths. Vernakalant was well tolerated and effective in patients with rapid-onset AF.

IMPLICATIONS

Vernakalant appears to be a good choice when AF is manifested postoperatively or exists with ischemic heart disease and valvular states. Tolerability-related data are promising, but a specific trial may be required to identify the causes of the deaths considered unrelated to vernakalant use. (Clin Ther. 2023;45:XXX-XXX) © 2023 Elsevier Inc.

Promising Therapies for Atrial Fibrillation and Ventricular Tachycardia

Sudden cardiac death due to arrhythmias, such as atrial fibrillation or ventricular tachycardia, account for 15-20% of all deaths. Myocardial infarction increases the burden of atrial fibrillation and ventricular tachycardia by structural and electrical remodeling of the heart. The current management of new-onset atrial fibrillation includes electric cardioversion with very high conversion rates and pharmacologic cardioversion, with less a than 50% conversion rate. If atrial fibrillation cannot be converted, the focus becomes the control of the symptoms ensuring a constant rhythm and rate control, without considering other contributory factors such as autonomic imbalance. Recently, a huge success was obtained by developing ablation techniques or addressing the vagal nerve stimulation. On the other hand, ventricular tachycardia is more sensitive to drug therapies. However, in cases of non-responsiveness to drugs, the usual therapeutic choice is represented by stereotactic ablative therapy or catheter ablation. This review focuses on these newly developed strategies for treatment of arrhythmias in clinical practice, specifically on vernakalant and low-level tragus stimulation for atrial fibrillation and stereotactic ablative therapy for drug-refractory ventricular tachycardia. These therapies are important for the significant improvement of the management of atrial fibrillation and ventricular tachycardia, providing: (1) a safer profile than current therapies, (2) higher success rate than current solutions, (3) low cost of delivery.

Treatments of new-onset atrial fibrillation in critically ill patients: a systematic review with meta-analysis

BACKGROUND

New-onset atrial fibrillation (NOAF) is common in hospitalised patients with critical illness and associated with worse outcomes. Several interventions are available in the management of NOAF, but the overall effectiveness and safety of these interventions compared with placebo or no treatment are unknown.

METHODS

We conducted a systematic review with meta-analysis and trial sequential analysis (TSA) of randomised clinical trials (RCT) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses, the Cochrane Collaboration, and Grading of Recommendations Assessment, Development and Evaluation statements. We searched RCTs assessing any pharmacological and non-pharmacological treatment compared with placebo or no treatment in critically ill hospitalised patients with NOAF. The primary outcomes were all-cause mortality, adverse events, and health-related quality of life.

RESULTS

We included 16 trials (n = 1891) evaluating seven interventions. All trials were adjudicated 'some concerns' or 'high risk' of bias. The evidence is very uncertain for mortality (RR 0.53, 95% CI 0.03-8.30), adverse events (RR 1.28, 95% CI 0.85-1.92), and treatment efficacy i.e. rhythm control (RR 1.54, 95% CI 1.20-1.97; TSA-adjusted CI 0.56-4.53) between pharmacological treatment and placebo/no treatment (very low certainty evidence). There were no data for health-related quality of life or most of our secondary outcomes.

CONCLUSIONS

The existing data are insufficient to firmly conclude on effects of any intervention against NOAF on any outcome in hospitalised patients with critical illness. Randomised trials of the most frequently used interventions against NOAF are warranted in these patients.

Cardioversion of recent-onset atrial fibrillation using intravenous antiarrhythmics: A European perspective

Pharmacological cardioversion using intravenous antiarrhythmic agents is commonly indicated in symptomatic patients with recent-onset atrial fibrillation (AF). Except in hemodynamically unstable patients who require emergency direct current electrical cardioversion, for the majority of hemodynamically stable patients, pharmacological cardioversion represents a valid option and requires the clinician to be familiar with the properties and use of antiarrhythmic agents. The main characteristics of selected intravenous antiarrhythmic agents for conversion of recent-onset AF, the reported success rates, and possible adverse events are discussed. Among intravenous antiarrhythmics, flecainide, propafenone, amiodarone, sotalol, dofetilide, ibutilide, and vernakalant are commonly used. Antazoline, an old antihistaminic agent with antiarrhythmic properties was also reported to give encouraging results in Poland. Intravenous flecainide and propafenone are the only Class I agents still recommended by recent guidelines. Intravenous new Class III agents as dofetilide and ibutilide have high and rapid efficacy in converting AF to sinus rhythm but require strict surveillance with electrocardiogram (ECG) monitoring during and after intravenous administration because of the potential risk of QT prolongation and Torsades de Pointes, which can be prevented and properly managed. Vernakalant, a partial atrial selective was shown to have a high success rate and to be safe in real-life use.

Systematic Review and Meta-analysis Appraising Efficacy and Safety of Vernakalant for Cardioversion of Recent-Onset Atrial Fibrillation

Vernakalant is a novel, relatively atrial-selective antiarrhythmic agent. Despite its good efficacy profile and rapid onset of action, there was still controversial evidence regarding vernakalant-related adverse events. We searched PubMed and Embase for studies that compared intravenous vernakalant with placebo or antiarrhythmic agents in patients with recent-onset atrial fibrillation (AF) lasting no more than 7 days. Efficacy and safety outcomes were the treatment-induced cardioversion rate within 90 minutes and adverse events after first exposure to study drug respectively. Nine randomized controlled trials enrolling 1296 patients were analyzed. Quantitative synthesis showed that vernakalant was superior to placebo for cardioversion of recent-onset AF within 90 minutes [49.7% vs. 6.2%, risk ratio (RR) 8.13, 95% confidence interval (CI) 5.35-12.36, P < 0.00001], and it did not achieve statistical significance in cardioversion when vernakalant was compared with ibutilide (62.4% vs. 47.3%, RR 1.32, 95% CI 1.00-1.73, P = 0.05). As for safety assessment, no significant differences were found in occurring serious adverse events (9.9% vs. 10.4%, RR 0.91, 95% CI 0.67-1.25, P = 0.57) and hypotension (5.3% vs. 3.3%, RR 1.53, 95% CI 0.86-2.73, P = 0.15) between vernakalant and comparator (either placebo, ibutilide, or amiodarone). There were trends that patients receiving vernakalant experienced more drug discontinuation (2.5% vs. 1.0%, RR 2.21, 95% CI 0.96-5.11, P = 0.06) and less any ventricular tachycardia (6.1% vs. 8.1%, RR 0.70, 95% CI 0.49-1.00, P = 0.05) than those receiving comparator, but the differences were not statistically significant. Furthermore, vernakalant was associated with a higher risk of bradycardia in comparison with comparator (6.3% vs. 1.1%, RR 4.04, 95% CI 1.67-9.75, P = 0.002). Vernakalant is effective in converting recent-onset AF to sinus rhythm rapidly, while significantly more bradycardia events are related to vernakalant in our meta-analysis.

Pharmacologic Cardioversion in Patients with Paroxysmal Atrial Fibrillation: A Network Meta-Analysis

PURPOSE

We sought to indirectly compare and rank antiarrhythmic agents focusing exclusively on adults with paroxysmal atrial fibrillation in order to identify the most effective for pharmacologic cardioversion over different time settings (4 h as primary, and 12, 24 h as secondary outcomes).

METHODS

We searched several databases from inception to March 2020 without language restrictions, ClinicalTrials.gov, references of reviews, and meeting abstract material. We included randomized controlled trials of patients with AF lasting ≤7 days comparing either two or more intravenous (i.v.) or oral (p.o.) pharmacologic cardioversion agents or an agent against placebo. For each outcome, we performed network meta-analysis based on the frequentist approach.

RESULTS

Forty-one trials (6013 patients) were included in our systematic review. Moderate confidence evidence suggests that i.v. vernakalant and flecainide have the highest conversion rate within 4 h, possibly allowing discharge from the emergency department and reducing hospital admissions. Intravenous and p.o. formulations of class IC antiarrhythmics (flecainide more so than propafenone) are superior regarding conversion rates within 12 h, while amiodarone efficacy is exhibited in a delayed fashion (within 24 h), especially if ranolazine is added.

CONCLUSION

Our network meta-analysis identified with sufficient power and consistency the most effective antiarrhythmics for pharmacologic cardioversion over different time settings, with vernakalant and flecainide exhibiting a safer and more efficacious profile toward faster cardioversion.

Vernakalant for cardioversion of recent-onset atrial fibrillation: a systematic review and meta-analysis

AIMS

To evaluate the efficacy and safety of vernakalant for the cardioversion of atrial fibrillation (AF).

METHODS AND RESULTS

We reviewed the literature for randomized trials that compared vernakalant to another drug or placebo in patients with AF of onset ≤7 days. We used a random-effects model to combine quantitative data and rated the quality of evidence using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation). From 441 total citations in MEDLINE, EMBASE, and CENTRAL (December 2018), we identified nine trials evaluating 1358 participants. Six trials compared vernakalant to placebo, two trials compared vernakalant to ibutilide, and one trial compared vernakalant to amiodarone. We found significant methodological bias in four trials. For conversion within 90 min, vernakalant was superior to placebo [50% conversion, risk ratio (RR) 5.15; 95% confidence interval (CI); 2.24-11.84, I2 = 91%], whereas we found no significant difference in conversion when vernakalant was compared with an active drug (56% vs. 24% conversion, RR 2.40; 95% CI 0.76-7.58, I2 = 94). Sinus rhythm was maintained at 24 h in 85% (95% CI 80-88%) of patients who converted acutely with vernakalant. Overall, we judged the quality of evidence for efficacy to be low based on inconsistency and suspected publication bias. There was no significant difference in the risk of significant adverse events between vernakalant and comparator (RR 0.95; 95% CI 0.70-1.28, I2 = 0, moderate quality evidence). Vernakalant is safe and effective for rapid and durable restoration of sinus rhythm in patients with recent-onset AF.

CONCLUSION

Vernakalant should be a first line option for the pharmacological cardioversion of patients with haemodynamically stable recent-onset AF without severe structural heart disease.

Vernakalant for Rapid Cardioversion of Recent-Onset Atrial Fibrillation: Results from the SPECTRUM Study

Aims

Rapid restoration of sinus rhythm using pharmacological cardioversion is commonly indicated in patients with symptomatic recent-onset atrial fibrillation (AF). The objectives of this large, international, multicenter observational study were to determine the safety and effectiveness of intravenous (IV) vernakalant for conversion of AF to sinus rhythm in daily practice.

Methods and Results

Consenting patients with symptomatic recent-onset AF (< 7 days) treated with IV vernakalant were enrolled and followed up to 24 h after the last infusion or until discharge, in order to determine the incidence of predefined serious adverse events (SAEs) and other observed SAEs and evaluate the conversion rate within the first 90 min. Overall, 2009 treatment episodes in 1778 patients were analyzed. The age of patients was 62.3 ± 13.0 years (mean ± standard deviation). Median AF duration before treatment was 11.1 h (IQR 5.4–27.0 h). A total of 28 SAEs occurred in 26 patients including 19 predefined SAEs, i.e., sinus arrest (n = 4, 0.2%), significant bradycardia (n = 11, 0.5%), significant hypotension (n = 2, 0.1%), and atrial flutter with 1:1 conduction (n = 2, 0.1%). There were no cases of sustained ventricular arrhythmias or deaths. All patients who experienced SAEs recovered fully (n = 25) or with sequelae (n = 1). Conversion rate to sinus rhythm was 70.2%, within a median of 12 min (IQR 8.0–28.0 min).

Conclusions

This large multicenter, international observational study confirms the good safety profile and the high effectiveness of vernakalant for the rapid cardioversion of recent-onset AF in daily hospital practice.

Revisiting Antiarrhythmic Drug Therapy for Atrial Fibrillation: Reviewing Lessons Learned and Redefining Therapeutic Paradigms

Since the clinical use of digitalis as the first pharmacological therapy for atrial fibrillation (AF) 235 years ago in 1785, antiarrhythmic drug therapy has advanced considerably and become a cornerstone of AF clinical management. Yet, a preventive or curative panacea for sustained AF does not exist despite the rise of AF global prevalence to epidemiological proportions. While multiple elevated risk factors for AF have been established, the natural history and etiology of AF remain incompletely understood. In the present article, the first section selectively highlights some disappointing shortcomings and current efforts in antiarrhythmic drug therapy to uncover reasons why AF is such a clinical challenge. The second section discusses some modern takes on the natural history of AF as a relentless, progressive fibro-inflammatory "atriomyopathy." The final section emphasizes the need to redefine therapeutic strategies on par with new insights of AF pathophysiology.

Vernakalant hydrochloride for the treatment of atrial fibrillation: evaluation of its place in clinical practice

Vernakalant is an intravenous anti-arrhythmic drug available in Europe, Canada and some countries in Asia for the restoration of sinus rhythm in acute onset atrial fibrillation. Currently, it is not available in USA because the US FDA have ongoing concerns about its safety. Vernakalant has a unique pharmacological profile of multi-ion channel activity and atrial-specificity that distinguishes it from other anti-arrhythmic drugs. This is thought to enhance efficacy but there are concerns of adverse events stemming from its diverse pharmacology. This ambiguity has prompted a review of the available clinical evidence on efficacy and safety to help re-evaluate its place in clinical practice.

Hemodynamic effects of Vernakalant in cardio-surgical ICU-patients treated for recent-onset postoperative atrial fibrillation

Postoperative atrial fibrillation (POAF) is one of the most frequent complications after cardiothoracic surgery and a predictor for postoperative mortality and prolonged ICU-stay. Current guidelines suggest the multi-channel inhibitor Vernakalant as a treatment option for rhythm control. However, rare cases of severe hypotension and cardiogenic shock following drug administration have been reported. To elucidate the impact of Vernakalant on hemodynamics, we included ten ICU patients developing POAF after elective cardiac surgery, all of them awake and breathing spontaneously, in this prospective trial. Patients received the recommended dosage of Vernakalant and were clinically observed and monitored (heart rate, invasive blood pressure, pulse oximetry, central venous pressure) in 1-minute-intervals for 20 minutes before- and 120 minutes after the first dose of Vernakalant. The median time from the end of surgery until occurrence of POAF amounted up to 52.8 [45.9–77.4] hours, it took 3.5 [1.2–10.1] hours from occurrence of POAF until the first application of Vernakalant. All patients received catecholamine support with epinephrine that was held steady and not dynamic throughout the observational phase. We noted stable hemodynamic conditions, with a trend towards a reduction in heart rate throughout the 120 minutes after drug administration. In 7 patients (70%), conversion to sustained sinus rhythm (SR) occurred within 8.0 minutes [6.0–9.0]. No serious adverse events (SAEs) were noted during the observation period. In this prospective trial in ICU-patients showing POAF after cardiac surgery, intravenous Vernakalant did not induce clinically relevant negative effects on patients’ hemodynamics but resulted in conversion to sustained SR after a median of 8.0 minutes in 7 out of ten patients.

Efficacy and safety of intravenous vernakalant for the rapid conversion of recent-onset atrial fibrillation: A meta-analysis

BACKGROUND

Atrial fibrillation is a common cardiac arrhythmia with increasing prevalence in the aging population. It is a major cause of emergency department visits worldwide. Vernakalant, a relatively new antiarrhythmic drug with selectively preferential effects on the atrial tissue is currently used in many European countries for the termination of recent-onset atrial fibrillation. Presently, the drug is still not approved by the United States Food and Drug Administration due to safety concerns. We evaluate the efficacy and safety of vernakalant for the conversion of recent-onset atrial fibrillation or atrial flutter into normal sinus rhythm (NSR).

METHODS

PubMed/MEDLINE (1993-2017), the Cochrane Central Register of Controlled Trials (2000-2017), and reference lists of relevant articles were searched for randomized controlled trials (RCTs) comparing vernakalant to a control drug and extracted subsequently.

RESULTS

Nine RCTs were identified and included in the meta-analysis. Pooled analysis of events extracted for a total of 1421 patients with recent-onset atrial fibrillation showed a statistically significant increase in cardioversion within 90 minutes from drug infusion (Relative Risk [RR], 6.61; 95% Confidence Interval [CI], 2.78 - 15.71; p < .00001). In terms of adverse events, vernakalant was considered safe in comparison to control drugs (RR, 0.80; 95% CI, 0.61-1.05; p = .11).

CONCLUSION

Vernakalant is effective for rapid conversion of recent-onset atrial fibrillation into NSR. However, although it showed a safe profile in terms of side effects in this analysis, we are still hesitant about this conclusion and few safety issues should be addressed within specific patients' subgroups.

Intravenous vernakalant in comparison with intravenous flecainide in the cardioversion of recent-onset atrial fibrillation

Background:

Pharmacological cardioversion of atrial fibrillation is a reasonable alternative for electrical cardioversion in acute atrial fibrillation. We compared the efficacy and safety of intravenous vernakalant and intravenous flecainide in patients with recent-onset (< 48 h) atrial fibrillation.

Methods:

A total of 200 consecutive patients, 100 patients undergoing cardioversion with intravenous vernakalant and 100 patients undergoing cardioversion with intravenous flecainide, were included in this single centre non-randomized retrospective study. The primary endpoint was conversion to sinus rhythm within 120 minutes from the drug administration.

Results:

Cardioversion was successful in 67% of patients treated with vernakalant and in 46% of patients treated with flecainide ( p=0.003). Vernakalant (odds ratio 1.99, 95% confidence interval 1.08–3.69, p=0.029) and female gender (odds ratio 2.48, 95% confidence interval 1.22–15.05, p=0.012) were significant predictors of successful cardioversion. The success rate of cardioversion was lowest among men treated with flecainide (36.9%). Patients treated with vernakalant were discharged earlier from the emergency department compared with those treated with flecainide (8.2 ± 4.7 h vs. 12.0 ± 6.0 h, p < 0.001). There was no difference in the complication rate between the groups. Vernakalant treated patients were older (59.3 ± 12.5 vs. 55.4 ± 13.0 years, p=0.03), had higher CHA2DS2-VASc score (1.4 ± 1.3 vs. 0.9 ± 1.2, p = 0.002) and were more often on beta-blocker medication (59% vs. 42%, p= 0.016) than flecainide treated patients.

Conclusion:

Vernakalant was safe, more effective and faster than flecainide in the cardioversion of recent-onset atrial fibrillation. The difference in efficacy was especially apparent among men.