The Drug And Pace Health cliNical Evaluation (DAPHNE) study: a randomized trial comparing sotalol versus beta-blockers to treat symptomatic atrial fibrillation in patients with brady-tachycardia syndrome implanted with an antitachycardia pacemaker

Hypertension management in patients with cardiovascular comorbidities

Arterial hypertension is a leading cause of death globally. Due to ageing, the rising incidence of obesity, and socioeconomic and environmental changes, its incidence increases worldwide. Hypertension commonly coexists with Type 2 diabetes, obesity, dyslipidaemia, sedentary lifestyle, and smoking leading to risk amplification. Blood pressure lowering by lifestyle modifications and antihypertensive drugs reduce cardiovascular (CV) morbidity and mortality. Guidelines recommend dual- and triple-combination therapies using renin–angiotensin system blockers, calcium channel blockers, and/or a diuretic. Comorbidities often complicate management. New drugs such as angiotensin receptor-neprilysin inhibitors, sodium–glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and non-steroidal mineralocorticoid receptor antagonists improve CV and renal outcomes. Catheter-based renal denervation could offer an alternative treatment option in comorbid hypertension associated with increased sympathetic nerve activity. This review summarises the latest clinical evidence for managing hypertension with CV comorbidities.

The Beneficial Effects of Beta Blockers on the Long-Term Prognosis of Patients With Premature Atrial Complexes

Aims

Premature atrial complexes (PACs) have been reported to increase the risk of adverse cardiovascular outcomes. Beta blockers at low dosages may help to reduce PAC symptoms, but it is unclear whether they can improve long-term outcomes.

Methods

Patients enrolled from a Holter cohort in a medical referral center were stratified into high-burden (≥100 beats/24 h) and low-burden (<100 beats/24 h) sub-cohorts, and propensity score matching between treatment groups and non-treatment groups was conducted for each sub-cohort.

Results

In the high-burden sub-cohort, after propensity score matching, the treatment group and non-treatment group respectively had 208 and 832 patients. The treatment group had significantly lower mortality rates than the non-treatment group [hazard ratio (HR) = 0.521, 95% confidence interval (CI) = 0.294–0.923, p = 0.025], but there was no difference in new stroke (HR = 0.830, 95% CI = 0.341–2.020, p = 0.681), and new atrial fibrillation (HR = 1.410, 95% CI = 0.867–2.292, p = 0.167) events. In the low-burden sub-cohort, after propensity score matching, there were 614 patients in the treatment group and 1,228 patients in the non-treatment group. Compared to the non-treatment group, up to 40% risk reduction in mortality was found in the treatment group (HR = 0.601, 95% CI = 0.396–0.913, p = 0.017), but no differences in new stroke (HR =0.969, 95% CI = 0.562–1.670, p = 0.910) or atrial fibrillation (HR = 1.074, 95% CI = 0.619–1.863, p = 0.800) were found.

Conclusions

Beta blockers consistently decreased long-term mortality in high-burden and low-burden patients. Interestingly, this effect was not achieved through reduction of new-onset stroke or AF, and further research is warranted.

Rate control strategies for atrial fibrillation

Atrial fibrillation (AF) is one of the main cardiac arrhythmias associated with higher risk of cardiovascular morbidity and mortality. AF can cause adverse symptoms and reduced quality of life. One of the strategies for the management of AF is rate control, which can modulate ventricle rate, alleviate adverse associated symptoms and improve the quality of life. As primary management of AF through rate control or rhythm is a topic under debate, the purpose of this review is to explore the rationale for the rate control approach in managing AF by considering the guidelines, recommendations and determinants for the choice of rate control drugs, including beta blockers, digoxin and non- dihydropyridine calcium channel blockers for patients with AF and other comorbidities and atrioventricular nodal ablation and pacing. Despite the limitations of rate control treatment, which may not be effective in preventing disease progression or in reducing symptoms in highly symptomatic patients, it is widely used for almost all patients with atrial fibrillation. Although rate control is one of the first line management of all patient with atrial fibrillation, several issues remain debateable.

Flecainide How and When: A Practical Guide in Supraventricular Arrhythmias

Transcatheter ablation was increasingly and successfully used to treat symptomatic drug refractory patients affected by supraventricular arrhythmias. Antiarrhythmic drug treatment still plays a major role in patient management, alone or combined with non-pharmacological therapies. Flecainide is an IC antiarrhythmic drug approved in 1984 from the Food and Drug Administration for the suppression of sustained ventricular tachycardia and later for acute cardioversion of atrial fibrillation and for sinus rhythm maintenance. Currently, flecainide is mostly used for sinus rhythm maintenance in atrial fibrillation (AF) patients without structural cardiomyopathy although recent studies enrolling different patient populations have demonstrated a good effectiveness and safety profile. How should we interpret the results of the CAST after the latest evidence? Is it possible to expand the indications of flecainide, and therefore, its use? This review aims to highlight the main characteristics of flecainide, as well as its optimal clinical use, delineating drug indications and contraindications and appropriate monitoring, based on the most recent evidence.

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.

Role of Metoprolol Succinate in the Treatment of Heart Failure and Atrial Fibrillation: A Systematic Review

BACKGROUND

Beta-blockers are one of the most important classes of cardiovascular agents and have been considered a cornerstone therapy in heart diseases, such as heart failure (HF) and atrial fibrillation (AF). Among different beta-blockers, metoprolol is a selective beta1-adrenergic antagonist, which has been extensively used since the 1970s.

AREAS OF UNCERTAINTY

Although current guidelines include recommendations for the use of controlled-release metoprolol succinate in specific HF and AF indications, and despite extensive clinical experience with metoprolol, comparative evidence on the use of metoprolol succinate compared with other beta-blockers in these indications is limited.

DATA SOURCES

We systematically reviewed the data from head-to-head studies directly comparing this compound with other beta-blockers in the treatment of HF or AF. Only clinical trials and observational studies were considered; no other limits were applied. The quality and relevance of retrieved articles were reviewed.

RESULTS

A total of 18 articles of the 353 articles identified were selected for inclusion; 12 HF articles and 6 for AF. Additional references were identified from the bibliographies of retrieved articles. The studies show that oral prophylaxis with an appropriate dose of metoprolol may reduce new incidents of AF in high-risk patients. Furthermore, metoprolol succinate is associated with significant mortality and morbidity benefits in the treatment of HF.

CONCLUSIONS

Despite the introduction of newer beta-blockers with differing clinical characteristics since its introduction, metoprolol succinate remains a useful drug in both HF and AF.

Sotalol

Sotalol is effective for treating atrial fibrillation (AF), ventricular tachycardia, premature ventricular contractions, and supraventricular tachycardia. Racemic (DL) sotalol inhibits the rapid component of the delayed rectifier potassium current. There is a near linear relationship between sotalol dosage and QT interval prolongation. However, in dose ranging trials in patients with AF, low-dose sotalol was not more effective than placebo. Orally administered sotalol has a bioavailability of nearly 100%. The only significant drug interactions are the need to avoid or limit use of concomitant drugs that cause QT prolongation, bradycardia, and/or hypotension.

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation frequently recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear. This is an update of a review previously published in 2008 and 2012.

OBJECTIVES

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

SEARCH METHODS

We updated the searches of CENTRAL in The Cochrane Library (2013, Issue 12 of 12), MEDLINE (to January 2014) and EMBASE (to January 2014). The reference lists of retrieved articles, recent reviews and meta-analyses were checked.

SELECTION CRITERIA

Two independent authors selected randomised controlled trials 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. Post-operative atrial fibrillation was excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up.

MAIN RESULTS

In this update three new studies, with 534 patients, were included making a total of 59 included studies comprising 21,305 patients. All included studies were randomised controlled trials. Allocation concealment was adequate in 17 trials, it was unclear in the remaining 42 trials. Risk of bias was assessed in all domains only in the trials included in this update.Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95% CI) 1.03 to 5.59, number needed to treat to harm (NNTH) 109, 95% CI 34 to 4985) and sotalol (OR 2.23, 95% CI 1.1 to 4.50, NNTH 169, 95% CI 60 to 2068) were associated with increased all-cause mortality. Other antiarrhythmics did not seem to modify mortality, but our data could be underpowered to detect mild increases in mortality for several of the drugs studied.Several class IA (disopyramide, quinidine), IC (flecainide, propafenone) and III (amiodarone, dofetilide, dronedarone, sotalol) drugs significantly reduced recurrence of atrial fibrillation (OR 0.19 to 0.70, number needed to treat to beneft (NNTB) 3 to 16). Beta-blockers (metoprolol) also significantly reduced atrial fibrillation recurrences (OR 0.62, 95% CI 0.44 to 0.88, NNTB 9).All analysed drugs increased withdrawals due to adverse affects and all but amiodarone, dronedarone and propafenone increased pro-arrhythmia. Only 11 trials reported data on stroke. None of them found any significant difference with the exception of a single trial than found less strokes in the group treated with dronedarone compared to placebo. This finding was not confirmed in others studies on dronedarone.We could not analyse heart failure and use of anticoagulation because few original studies reported on these measures.

AUTHORS' CONCLUSIONS

Several class IA, IC and III drugs, as well as class II drugs (beta-blockers), are moderately effective in maintaining sinus rhythm after conversion of atrial fibrillation. However, they increase adverse events, including pro-arrhythmia, and some of them (disopyramide, quinidine and sotalol) may increase mortality. Possible benefits on clinically relevant outcomes (stroke, embolism, heart failure) remain to be established.

Comparative effectiveness of antiarrhythmic drugs on cardiovascular hospitalization and mortality in atrial fibrillation

AIM

To assess, through a systematic review, evidence for the effects of antiarrhythmic drugs (AADs) on cardiovascular (CV) hospitalization and mortality.

MATERIALS & METHODS

English language articles were identified using MEDLINE, EMBASE and the Cochrane Clinical Trial Registry and were screened for study applicability and methodological quality.

RESULTS

Out of 3526 identified studies, 38 were selected for analysis (19 evaluated individual AADs, 13 compared rate- versus rhythm-control strategies, and 6 evaluated multiple AADs but did not report outcomes for individual agents). None of the studies examining individual AADs employed the CV hospitalization end point used in ATHENA (the reference trial). There were no head-to-head comparisons of individual AADs on CV hospitalization. Most high-quality studies used multidrug rate- versus rhythm-control strategies.

CONCLUSION

Assessment of the comparative effectiveness of individual AADs on CV hospitalization and mortality end points is not possible with the current evidence.

Risk factors for bradycardia requiring pacemaker implantation in patients with atrial fibrillation

Symptomatic bradycardia may complicate atrial fibrillation (AF) and necessitate a permanent pacemaker. Identifying patients at increased risk for symptomatic bradycardia may reduce associated morbidities and health care costs. The aim of this study was to investigate predictors for developing bradycardia requiring a permanent pacemaker in patients with AF. The records of all patients treated for AF or atrial flutter in an academic hospital's emergency department from August 1, 2005, to July 31, 2008, were reviewed. Survival and the presence of a pacemaker as of November 1, 2011, were determined. Cases were defined as patients with pacemakers placed for bradycardia after their AF diagnoses. Patients without pacemakers who were followed constituted the control group. Variables for the logistic regression analysis were identified a priori. A post hoc model was fit adjusting for AF type and atrioventricular nodal blocker use. Of the 362 patients in the cohort, 119 cases had permanent pacemakers implanted for bradycardia after AF diagnosis, and 243 controls were alive without pacemakers. The median follow-up time was 4.5 years (interquartile range 3.8 to 5.4). Odds ratios were determined for age at the time of AF diagnosis (1.02, 95% confidence interval [CI] 1 to 1.04), female gender (1.58, 95% CI 0.95 to 2.63), previous heart failure (2.72, 95% CI 1.47 to 5.01), and African American race (0.33, 95% CI 0.12 to 0.94). The post hoc model identified permanent AF (odds ratio 2.99, 95% CI 1.61 to 5.57) and atrioventricular nodal blocker use (odds ratio 1.43, 95% CI 0.85 to 2.4). In conclusion, in patients with AF, heart failure and permanent AF each nearly triple the odds of developing bradycardia requiring a permanent pacemaker; although not statistically significant, our results suggest that women are more likely and African Americans less likely to develop bradycardia requiring pacemaker implantation.

Usefulness of continuous electrocardiographic monitoring for atrial fibrillation

The problem of early recognition of atrial fibrillation (AF) is greatly aggravated by the often silent nature of the rhythm disturbance. In about 1/3 of patients with this arrhythmia, patients are not aware of the so-called asymptomatic AF. In the past 15 years, the diagnostic data provided by implanted pacemakers and defibrillators have dramatically increased knowledge about silent AF. The unreliability of symptoms to estimate AF burden and to identify patients with and without AF has been pointed out not only by pacemaker trials but also in patients without implanted devices. The technology for continuous monitoring of AF has been largely validated. It is a powerful tool to detect silent paroxysmal AF in patients without previously documented arrhythmic episodes, such as those with cryptogenic stroke or other risk factors. Early diagnosis triggers earlier treatment for primary or secondary stroke prevention. Today, new devices are also available for pure electrocardiographic monitoring, implanted subcutaneously using a minimally invasive technique. In conclusion, this recent and promising technology adds relevant clinical and scientific information to improve risk stratification for stroke and may play an important role in testing and tailoring the therapies for rhythm and rate control.

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most frequent sustained arrhythmia. AF recurs frequently after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear.

OBJECTIVES

To determine, in patients who recovered sinus rhythm after AF, the effect of long-term treatment with antiarrhythmic drugs on death, stroke and embolism, adverse effects, pro-arrhythmia, and recurrence of AF.

SEARCH METHODS

We updated the searches of CENTRAL on The Cochrane Libary (Issue 1 of 4, 2010), MEDLINE (1950 to February 2010) and EMBASE (1966 to February 2010). The reference lists of retrieved articles, recent reviews and meta-analyses were checked.

SELECTION CRITERIA

Two independent reviewers selected randomised controlled trials comparing any antiarrhythmic with a control (no treatment, placebo or drugs for rate control) or with another antiarrhythmic, in adults who had AF and in whom sinus rhythm was restored. Post-operative AF was excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up.

MAIN RESULTS

In this update, 11 new studies met inclusion criteria, making a total of 56 included studies, comprising 20,771 patients. Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95%CI) 1.03 to 5.59, number needed to harm (NNH) 109, 95%CI 34 to 4985) and sotalol (OR 2.47, 95%CI 1.2 to 5.05, NNH 166, 95%CI 61 to 1159) were associated with increased all-cause mortality. Other antiarrhythmics did not seem to modify mortality.Several class IA (disopyramide, quinidine), IC (flecainide, propafenone) and III (amiodarone, dofetilide, dronedarone, sotalol) drugs significantly reduced recurrence of AF (OR 0.19 to 0.70, number needed to treat (NNT) 3 to 16). Beta-blockers (metoprolol) also reduced significantly AF recurrence (OR 0.62, 95% CI 0.44 to 0.88, NNT 9).All analysed drugs increased withdrawals due to adverse affects and all but amiodarone, dronedarone and propafenone increased pro-arrhythmia. We could not analyse other outcomes because few original studies reported them.

AUTHORS' CONCLUSIONS

Several class IA, IC and III drugs, as well as class II (beta-blockers), are moderately effective in maintaining sinus rhythm after conversion of atrial fibrillation. However, they increase adverse events, including pro-arrhythmia, and some of them (disopyramide, quinidine and sotalol) may increase mortality. Possible benefits on clinically relevant outcomes (stroke, embolisms, heart failure) remain to be established.

Recent Publications on Medications and Pharmacy

Hospital Pharmacy presents this feature to keep pharmacists abreast of new publications in the medical/pharmacy literature. Articles of interest regarding a broad scope of topics are abstracted monthly.