Interventions for the treatment of atrial fibrillation: A systematic literature review and meta-analysis

Thrombocytopenia and Mortality Risk in Patients With Atrial Fibrillation: An Analysis From the START Registry

Background

Thrombocytopenia is associated with increased mortality in the general population, but few data exist in patients with atrial fibrillation (AF) taking oral anticoagulants. We investigated factor determinants of thrombocytopenia in a large cohort of patients affected by AF and its association with total mortality.

Methods and Results

Multicenter prospective cohort study, including 5215 patients with AF from the START (Survey on Anticoagulated Patients Register) registry, 3877 (74.3%) and 1338 (25.7%) on vitamin K or non–vitamin K antagonist oral anticoagulants, respectively. Thrombocytopenia was defined by a platelet count <150×10⁹/L. Determinants of thrombocytopenia were investigated, and all‐cause mortality was the primary survival end point of the study. Thrombocytopenia was present in 592 patients (11.4%). At multivariable logistic regression analysis, chronic kidney disease (odds ratio [OR], 1.257; P=0.030), active cancer (OR, 2.065; P=0.001), liver cirrhosis (OR, 7.635; P<0.001), and the use of diuretics (OR, 1.234; P=0.046) were positively associated with thrombocytopenia, whereas female sex (OR, 0.387; P<0.001) and the use of calcium channel blockers (OR, 0.787; P=0.032) were negatively associated. During a median follow‐up of 19.2 months (9942 patient‐years), 391 deaths occurred (rate, 3.93%/year). Mortality rate increased from 3.8%/year to 9.9%/year in patients with normal platelet count and in those with moderate‐severe thrombocytopenia, respectively (log‐rank test, P=0.009). The association between moderate‐severe thrombocytopenia and mortality persisted after adjustment for CHA₂DS₂VASc score (hazard ratio, 2.431; 95% CI, 1.254–4.713; P=0.009), but not in the fully adjusted multivariable Cox regression analysis model.

Conclusions

Thrombocytopenia is common in patients with AF. Despite an increased incidence of mortality, thrombocytopenia was not associated with mortality at multivariable analysis. Thrombocytopenia may reflect the presence of comorbidities associated with poor survival in AF.

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation often recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence. This is an update of a review previously published in 2006, 2012 and 2015.

OBJECTIVES

To determine the effects of long-term treatment with antiarrhythmic drugs on death, stroke, drug adverse effects and recurrence of atrial fibrillation in people who had recovered sinus rhythm after having atrial fibrillation.

SEARCH METHODS

We updated the searches of CENTRAL, MEDLINE and Embase in January 2019, and ClinicalTrials.gov and WHO ICTRP in February 2019. We checked the reference lists of retrieved articles, recent reviews and meta-analyses.

SELECTION CRITERIA

Two authors independently selected randomised controlled trials (RCTs) comparing any antiarrhythmic drug with a control (no treatment, placebo, drugs for rate control) or with another antiarrhythmic drug in adults who had atrial fibrillation and in whom sinus rhythm was restored, spontaneously or by any intervention. We excluded postoperative atrial fibrillation.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed quality and extracted data. We pooled studies, if appropriate, using Mantel-Haenszel risk ratios (RR), with 95% confidence intervals (CI). All results were calculated at one year of follow-up or the nearest time point.

MAIN RESULTS

This update included one new study (100 participants) and excluded one previously included study because of double publication. Finally, we included 59 RCTs comprising 20,981 participants studying quinidine, disopyramide, propafenone, flecainide, metoprolol, amiodarone, dofetilide, dronedarone and sotalol. Overall, mean follow-up was 10.2 months.All-cause mortalityHigh-certainty evidence from five RCTs indicated that treatment with sotalol was associated with a higher all-cause mortality rate compared with placebo or no treatment (RR 2.23, 95% CI 1.03 to 4.81; participants = 1882). The number need to treat for an additional harmful outcome (NNTH) for sotalol was 102 participants treated for one year to have one additional death. Low-certainty evidence from six RCTs suggested that risk of mortality may be higher in people taking quinidine (RR 2.01, 95% CI 0.84 to 4.77; participants = 1646). Moderate-certainty evidence showed increased RR for mortality but with very wide CIs for metoprolol (RR 2.02, 95% CI 0.37 to 11.05, 2 RCTs, participants = 562) and amiodarone (RR 1.66, 95% CI 0.55 to 4.99, 2 RCTs, participants = 444), compared with placebo.We found little or no difference in mortality with dofetilide (RR 0.98, 95% CI 0.76 to 1.27; moderate-certainty evidence) or dronedarone (RR 0.86, 95% CI 0.68 to 1.09; high-certainty evidence) compared to placebo/no treatment. There were few data on mortality for disopyramide, flecainide and propafenone, making impossible a reliable estimation for those drugs.Withdrawals due to adverse eventsAll analysed drugs increased withdrawals due to adverse effects compared to placebo or no treatment (quinidine: RR 1.56, 95% CI 0.87 to 2.78; disopyramide: RR 3.68, 95% CI 0.95 to 14.24; propafenone: RR 1.62, 95% CI 1.07 to 2.46; flecainide: RR 15.41, 95% CI 0.91 to 260.19; metoprolol: RR 3.47, 95% CI 1.48 to 8.15; amiodarone: RR 6.70, 95% CI 1.91 to 23.45; dofetilide: RR 1.77, 95% CI 0.75 to 4.18; dronedarone: RR 1.58, 95% CI 1.34 to 1.85; sotalol: RR 1.95, 95% CI 1.23 to 3.11). Certainty of the evidence for this outcome was low for disopyramide, amiodarone, dofetilide and flecainide; moderate to high for the remaining drugs.ProarrhythmiaVirtually all studied antiarrhythmics showed increased proarrhythmic effects (counting both tachyarrhythmias and bradyarrhythmias attributable to treatment) (quinidine: RR 2.05, 95% CI 0.95 to 4.41; disopyramide: no data; flecainide: RR 4.80, 95% CI 1.30 to 17.77; metoprolol: RR 18.14, 95% CI 2.42 to 135.66; amiodarone: RR 2.22, 95% CI 0.71 to 6.96; dofetilide: RR 5.50, 95% CI 1.33 to 22.76; dronedarone: RR 1.95, 95% CI 0.77 to 4.98; sotalol: RR 3.55, 95% CI 2.16 to 5.83); with the exception of propafenone (RR 1.32, 95% CI 0.39 to 4.47) for which the certainty of evidence was very low and we were uncertain about the effect. Certainty of the evidence for this outcome for the other drugs was moderate to high.StrokeEleven studies reported stroke outcomes with quinidine, disopyramide, flecainide, amiodarone, dronedarone and sotalol. High-certainty evidence from two RCTs suggested that dronedarone may be associated with reduced risk of stroke (RR 0.66, 95% CI 0.47 to 0.95; participants = 5872). This result is attributed to one study dominating the meta-analysis and has yet to be reproduced in other studies. There was no apparent effect on stroke rates with the other antiarrhythmics.Recurrence of atrial fibrillationModerate- to high-certainty evidence, with the exception of disopyramide which was low-certainty evidence, showed that all analysed drugs, including metoprolol, reduced recurrence of atrial fibrillation (quinidine: RR 0.83, 95% CI 0.78 to 0.88; disopyramide: RR 0.77, 95% CI 0.59 to 1.01; propafenone: RR 0.67, 95% CI 0.61 to 0.74; flecainide: RR 0.65, 95% CI 0.55 to 0.77; metoprolol: RR 0.83 95% CI 0.68 to 1.02; amiodarone: RR 0.52, 95% CI 0.46 to 0.58; dofetilide: RR 0.72, 95% CI 0.61 to 0.85; dronedarone: RR 0.85, 95% CI 0.80 to 0.91; sotalol: RR 0.83, 95% CI 0.80 to 0.87). Despite this reduction, atrial fibrillation still recurred in 43% to 67% of people treated with antiarrhythmics.

AUTHORS' CONCLUSIONS

There is high-certainty evidence of increased mortality associated with sotalol treatment, and low-certainty evidence suggesting increased mortality with quinidine, when used for maintaining sinus rhythm in people with atrial fibrillation. We found few data on mortality in people taking disopyramide, flecainide and propafenone, so it was not possible to make a reliable estimation of the mortality risk for these drugs. However, we did find moderate-certainty evidence of marked increases in proarrhythmia and adverse effects with flecainide.Overall, there is evidence showing that antiarrhythmic drugs increase adverse events, increase proarrhythmic events and some antiarrhythmics may increase mortality. Conversely, although they reduce recurrences of atrial fibrillation, there is no evidence of any benefit on other clinical outcomes, compared with placebo or no treatment.

Antiarrhythmic therapy in the treatment of atrial fibrillation: yesterday, today, tomorrow

Atrial fibrillation (AF) is the most common heart rhythm disorder encountered in clinical practice. Each year, the number of patients with AF significantly increases. It is associated with an increase of life expectancy and frequency of cardiovascular pathologies. Treatment of AF remains one of the most difficult tasks of modern cardiology. Currently, only a few antiarrhythmic drugs are available for use in Russia. More and more new attempts are being made to create a universal antiarrhythmic drug with a high level of anti-relapsing efficacy and adverse effects. The accumulated information suggests that the tactics of management of patients with arrhythmias will be intended to improving the new surgical and interventional treatment methods with use of anticoagulants and antiarrhythmic drugs. The multidisciplinary team of specialists on AF treatment should include an expert (cardiologist) in antiarrhythmic drug therapy, an interventional electrophysiologist, and a cardiac surgeon — master the technology of interventional or surgical ablation. Effective interaction of specialists of various levels will improve the results of rhythm control and prevention of complications in patients with AF.

Transtelephonic ECG Monitoring to Guide Outpatient Antiarrhythmic Drug Therapy in Patients With Non-Permanent Atrial Fibrillation: Efficacy and Safety From a Single-Center Experience

Initiation of antiarrhythmic drug therapy (AADx) for atrial fibrillation (AF) on an outpatient basis requires intensive ECG monitoring in order to assess antiarrhythmic efficacy as well as ECG signals of potential proarrhythmia. Dronedarone (DRO) reduces cardiovascular endpoints in AF patients fulfilling criteria of the ATHENA trial [1]. In the present study transtelephonic ECG monitoring was used to guide initiation of AADx in AF patients fulfilling the ATHENA criteria. In 19 consecutive patients (37% female; age 65+10 years; LVEF 62+7%; mean CHA2DS2-VASc score 2.9 + 1.6 (median=2), with symptomatic non-permanent AF and additional cardiovascular risk factors, DRO was prescribed as AADx of first choice. Initiation of therapy and follow-up were monitored by transtelephonic ECG recordings (VITAPHONE™100 IR; Vitaphone GmbH; Germany). In patients with persistent AF, electrical cardioversion was performed on an outpatient basis when DRO was started. Patients were followed for changes in QT intervals as well as AF recurrency. ECGs were transmitted according to a scheduled FU form as well as any time in case of pts symptoms. Patients in whom DRO did not prevent AF recurrence were switched to alternative AADx, or to pulmonary vein isolation (PVI), respectively. At the end of long-term follow-up, DRO alone was successful in preventing AF recurrence in 5 of 19 patients (26%). When pts who responded to AADx of second or third choice or who underwent PVI were included, SR could be maintained in 17/19 pts (89%). No patient required discontinuation of AADx due to ventricular depolarization abnormalities, symptomatic bradycardia or pathologic QT prolongation. In conclusion, transtelephonic ECG transmission is useful for close rhythm monitoring during initiation and follow-up of AADx, also during change from DRO to other AADx. DRO was effective to prevent AF recurrence in 26% of patients during a mean long-term follow-up of more than 30 months - which is well in line with data from the literature.

Dronedarone, amiodarone and other antiarrhythmic drugs, and acute liver injuries: a case-referent study

BACKGROUND

Spontaneous reports of acute liver injuries (ALI) in patients taking dronedarone triggered an EMA alert in 2011. This study aimed to assess the risk of ALI for class III antiarrhythmic drugs controlling for the use of other potential ALI-inducing drugs.

METHODS

Between 2010 and 2014, consecutive ALI cases (≥50 years-old) were identified across Germany. ALI was defined as a new increase in at least one of the transaminases ≥3 times the upper limit of normal (ULN) or ≥2 ULN if alkaline phosphatase, with ("definite" case) or without ("biochemical" case) suggestive signs/symptoms of ALI, excluding other liver diseases. Recruited community controls were matched to cases on gender, age and inclusion date. Exposure to antiarrhythmic drugs and co-medication up to 2 years before ALI onset was informed by patients and confirmed by physicians' prescriptions. Adjusted Odds Ratios (aOR) were obtained from conditional multivariable logistic regressions, adjusted for a multivariate disease risk score and co-medication.

RESULTS

252 cases and 1081 matched controls were included (59.1% females; mean age: 64 years). Exposure to class III antiarrhythmic drugs was 4.0% in cases and 1.5% in controls, aOR = 3.6 (95% CI: 1.6-8.4). Associations with exposure to dronedarone and amiodarone were respectively 3.1 (95% CI: 0.7-14. 8) and 5.90 (1.7-20.0). Restricting the analysis to definite or severe ALI cases did not change these results.

CONCLUSIONS

Class III antiarrhythmic drugs were associated with ALI, amiodarone displaying the highest risk, and results were robust to case definitions. Continued vigilance is needed for patients taking these drugs.

Efficacy of Intravenous and Oral Sotalol in Pharmacologic Conversion of Atrial Fibrillation: A Systematic Review and Meta-Analysis

Objectives: The role of sotalol is well established for the maintenance of sinus rhythm after successful conversion of atrial fibrillation (AF). However, its role in pharmacologic conversion of AF is poorly defined. The purpose of this study is to compare the efficacy of sotalol to that of other antiarrhythmic agents for AF conversion. Methods: Standard methods of meta-analysis were employed. Full-text publications of clinical trials in English that compared the efficacy of sotalol to that of other antiarrhythmics or placebo/no treatment were eligible for inclusion. Results: A systematic review revealed 10 eligible publications. Sotalol was superior to placebo and/or no antiarrhythmic therapy in AF conversion, with a relative success of 24 (95% CI 4.7-119, p < 0.001). Sotalol was not significantly different from class IA antiarrhythmic drugs. Similarly, sotalol was not different from class IC antiarrhythmic drugs or amiodarone in terms of conversion efficacy. In one study, sotalol was less effective than high-dose ibutilide (2 mg), with a relative success of 0.248 (95% CI 0.128-0.481, p < 0.001). Ibutilide caused more proarrhythmia. Conclusions: Sotalol is as effective as class IA and class IC antiarrhythmic agents, and it is also as effective as amiodarone for pharmacologic conversion of AF. Only ibutilide at a high dose showed a greater conversion rate of AF.

Sotalol versus Amiodarone in Treatment of Atrial Fibrillation

The availability of intravenous (IV) Sotalol has equalized the treatment options since both amiodarone and sotalol are available in both IV and oral formulations. A review of the efficacy of sotalol as compared to amiodarone both for conversion of atrial fibrillation (AF) and maintenance of normal sinus rhythm (NSR) following cardiac surgery was undertaken. Standard methods of meta-analysis were employed. Full text publications of clinical trials written in English that compared the efficacy of sotalol to amiodarone were included in the analysis. For the conversion of AF to NSR, five studies were found eligible for the analysis. Two studies clinically compared sotalol to amiodarone for the maintenance of NSR after cardiac surgery. The common relative success of sotalol was 0.947 (95Cl: 0.837 to 1.071, P = 0.385), revealing essentially no differences in efficacy for conversion between amiodarone and sotalol. The average conversion rate was 47% with sotalol and 52% with amiodarone. The conversion rates were lower for persistent AF (sotalol 22% and amiodarone 27%), while greatest for recent onset AF (88% sotalol and 77% for amiodarone). The risk of developing post-operative atrial fibrillation was practically the same in both regimes, relative risk = 1.214 (95% CI: 0.815-1.808, p=0.339). In summary, sotalol and amiodarone are equally effective in AF conversion and maintenance of NSR post-cardiac surgery.

The efficacy and tolerability of commonly used agents to prevent recurrence of atrial fibrillation after successful cardioversion

A number of therapeutic strategies exist for the restoration and maintenance of sinus rhythm in patients presenting with atrial fibrillation. The acute success rate with electrical cardioversion is high. However, many patients relapse into atrial fibrillation. A major challenge faced by those who care for patients with atrial fibrillation is the long-term maintenance of sinus rhythm whilst avoiding treatment-related adverse effects. This review examines the efficacy and tolerability of conventional anti-arrhythmic drugs for the secondary prevention of atrial fibrillation in the post-cardioversion period.

Landiolol hydrochloride for prevention of atrial fibrillation after cardiac surgery: a meta-analysis

BACKGROUND

Atrial fibrillation (AF) is the most common arrhythmic complication after cardiac surgery. Several studies have compared the efficacy of landiolol and placebo or other agents in preventing new-onset AF in patients after cardiac surgery. In this study, we conducted a meta-analysis to determine whether landiolol is effective in preventing new-onset AF after cardiac surgery.

METHODS AND RESULTS

Five randomized controlled trials and two retrospective analyses were included in this study. The clinical outcomes of interest were the occurrence of AF after cardiac surgery and major complications. Meta-analysis was performed using RevMan 5.0.18 software, and pooled estimates of the effect were reported as risk ratios (RR) with 95% confidence intervals (CI). The results of this meta-analysis indicate that landiolol is significantly associated with a decreased risk of occurrence of AF after cardiac surgery (RR = 0.33; 95% CI: 0.23-0.48; P < 0.00001) and is not associated with an increased risk of major complications (RR = 0.79; 95% CI: 0.43-1.45; P = 0.45) compared with the control group.

CONCLUSION

Landiolol administration in the perioperative period can reduce the occurrence of AF after cardiac surgery without increasing the risk of major complications. It can be used to prevent new-onset AF safely after cardiac surgery.

Catheter-based arterial sympathectomy: hypertension and beyond

Transluminal ablation of renal artery sympathetic nerves has been shown to provide a significant and durable reduction in blood pressure with very low complication rates. Additional publications have documented improvement in insulin sensitivity, obstructive sleep apnea indices, and frequency and severity of congestive heart failure in subgroups undergoing the procedure. This technology may provide effective management of other diseases in which there is autonomic imbalance. Available data are reviewed with the intent to provoke interest within the interventional radiology community in this novel technology, which may allow minimally invasive treatment of many important chronic medical conditions.

Advances in the management of atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia worldwide, increasing in incidence with the aging population. Substantial morbidity and mortality accompany its diagnosis. Management should focus on rate and rhythm management, on reducing thromboembolic risk, and also potentially on targeting the mechanisms responsible for its perpetuation. Current antiarrhythmic therapy has only modest efficacy and substantial side effects, and anticoagulation regimes are cumbersome and require regular monitoring. Novel anticoagulants and antiarrhythmics hold the promise of improved efficacy and safety. This review covers current therapy for AF, major advances in pharmacological management and future directions for therapy.