The incidence of asymptomatic paroxysmal atrial fibrillation in patients treated with propranolol or propafenone

Effect of β-blockers on triggering of symptomatic atrial fibrillation by anger or stress

BACKGROUND

Anger and stress can trigger episodes of atrial fibrillation (AF) in patients with a history of AF.

OBJECTIVE

The purpose of this study was to determine whether β-blockers can protect against emotionally triggered AF.

METHODS

In this prospective, controlled, electronic diary-based study of emotions preceding AF, patients with a history of paroxysmal or persistent AF (N = 91) recorded their rhythm on event monitors at the time of AF symptoms and completed a diary entry querying mood states (eg, anger and stress) for the preceding 30 minutes (pre-AF "case period") for 1 year. Also, patients underwent monthly 24-hour Holter monitoring during which they were prompted to complete a diary entry twice per hour. Diaries recorded during sinus rhythm comprise controls. Patients' exposure to each emotion was compared between the pre-AF case period and control periods by using generalized estimating equation modeling, as well as interactions between β-blocker use and emotion tested.

RESULTS

Sixty percent were prescribed β-blockers. A total of 163 symptomatic AF episodes (in 34 patients) and 11,563 Holter-confirmed sinus rhythm control periods had associated diary data. Overall, the likelihood of an AF episode was significantly higher during anger or stress. This effect, however, was significantly attenuated in patients on β-blockers (odds ratio 22.5; 95% confidence interval 6.7-75.4, P < .0001 for patients not prescribed β-blockers vs odds ratio 4.0, 95% confidence interval 1.7-9.5, P = .002 for those prescribed β-blockers; P = .02 for the interaction). Exclusion of patients on sotalol did not affect findings.

CONCLUSION

Anger or stress can trigger AF, but use of β-blockers greatly attenuates this deleterious physiological response.

Long-term success and follow-up after atrial fibrillation ablation

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia in clinical practice. It is associated with significant morbidity and mortality and has been identified as an independent risk factor for ischemic stroke and thromboembolic events. Catheter ablation has become an established rhythm control therapy in patients with highly symptomatic drug-refractory AF. The definition of ablation success remains controversial since current symptom-based or intermittent electrocardiogram monitoring strategies fail to sufficiently disclose rhythm outcome. This failure is mainly related to the high incidence of asymptomatic AF recurrences, the unpredictable nature of arrhythmia relapses, and the poor correlation of symptoms and AF episodes. There is a clear correlation between the intensity of the monitoring strategy and the sensitivity for it to detect arrhythmia recurrences. Furthermore, several clinical studies assessing the long-term efficacy of catheter ablation procedures have reported late AF recurrences in patients who were initially considered responders to catheter ablation. In certain subsets of patients, precise long-term monitoring may help to guide therapy, e.g. patients in whom withdrawal of antithrombotic therapy may be considered if they are free of arrhythmia recurrences. Recently, sub-cutaneous implantable cardiac monitors (ICM) have been introduced for prolonged and continuous rhythm monitoring. The performance of a leadless ICM equipped with a dedicated AF detection algorithm has recently been assessed in a clinical trial demonstrating a high sensitivity and overall accuracy for identifying patients with AF. The clinical impact of ICM-based follow-up strategies, however, has to be evaluated in prospective clinical trials.

Atrial fibrillation and heart failure in the elderly

Atrial fibrillation (AF) is a common clinical problem in elderly patients and especially in those with heart failure (HF). It is a major risk factor for serious cardiovascular events, such as stroke, HF and premature death. Both the prevalence and incidence of AF increase with age and its prevalence in the United States are estimated at more than 2.2 million, with nearly 75% of patients aged >65 years. Aging-related atrial remodeling with fibrosis, dilation and mitochondrial DNA mutations predispose elderly patients to AF. Current management options for AF, including rate control and anticoagulation therapy, can be successfully applied to the elderly population. New antiarrhythmic and anticoagulation medications such as dronedarone and dabigatran, respectively, can impact the approach to therapy in the elderly. Non-pharmacological options such as catheter-based ablation have also gained prominence and have been incorporated into the guidelines for management of AF. However, more trials in the elderly and very elderly segments are needed to clarify the safety and long-term efficacy of the new treatment options.

Clinical characteristics of patients with asymptomatic recurrences of atrial fibrillation in the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-Atrial Fibrillation (GISSI-AF) trial

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia that frequently recurs after restoration of sinus rhythm. In a consistent percentage of cases, AF recurrences are asymptomatic, thus making its clinical management difficult in relation to both therapeutic efficacy and thromboembolic risk.

METHODS

The GISSI-AF trial enrolled 1,442 patients in sinus rhythm with previous AF episodes. Patients were randomized to valsartan or placebo and followed for 12 months. To improve the likelihood of detecting arrhythmic recurrences, arrhythmic follow-up was based on both programmed or symptom-related control visits and transtelephonic electrocardiographic transmissions. The present post hoc analysis was performed on 1,638 arrhythmic episodes that occurred in 623 patients.

RESULTS

Asymptomatic AF recurrences were present in 49.5% of patients. In multivariable analysis, asymptomatic AF recurrences were significantly associated with a longer duration of qualifying arrhythmias (odds ratio [95% CI] 1.57 (1.26-1.97), P < .0001). A lower ventricular response (P < .001) and a longer duration of the arrhythmic recurrence (P < .001) characterized asymptomatic episodes. Patients with asymptomatic events were more likely to be in AF at the time of electrocardiographic control at the end of the 12-month follow-up (adjusted odds ratio [95% CI] 4.9 (2.8-8.4), P < .001). Moreover, a higher CHADS(2) (Congestive heart failure, history of Hypertension, Age≥75 years, Diabetes mellitus, and past history of Stroke or TIA doubled) score and a more frequent use of amiodarone, calcium-channel blockers, and digitalis characterized patients with asymptomatic, whereas 1C drugs were more often used in subjects with symptomatic recurrences.

CONCLUSION

Asymptomatic AF recurrences were frequent in the GISSI-AF study population in patients who were more likely to develop persistent-permanent AF and were characterized by an increased thromboembolic risk.

Is there a role for bi-atrial pacing resynchronisation therapy in the management of drug-refractory atrial fibrillation in patients unsuitable for left atrial ablation?

BACKGROUND

This retrospective cohort study evaluated whether long term outcome of atrial resynchronisation therapy using bi-atrial pacing (BiaP) to treat atrial fibrillation (AF) was effective in patients deemed unfit for left atrial (LA) ablation procedures.

METHODS AND RESULTS

The patient population comprised 2 groups: those deemed suitable for left LA ablation (n=14) and those who were not (n = 17). Both groups underwent BiaP and outcomes were evaluated by comparing symptoms, AF duration, admissions and antiarrhythmic drugs (AAD) for an equal period of time pre and post implantation. Median follow-up was 24 months (range 8-66 months) for the unsuitable group and 31 months (range 7-84 months) for the suitable group. Efficacy in reduction of both AF and symptoms was similar (P = 0.44) in both groups (unsuitable group: 13/17; suitable group: 8/14). There was significant improvement in median AF episodes/week pre and post BiaP in both groups (unsuitable group AF reduction: 5 days/week, P = 0.001; suitable group AF reduction: 4.9 days/week, P = 0.03); the improvement was similar in both groups (P = 0.33). There was a significant reduction in the median number of admissions for AF in both groups (unsuitable group: P = 0.003; suitable group: P = 0.01) and this reduction was also similar (P = 0.70). The median number of AAD was also reduced to a similar degree (P = 0.83) in both groups (suitable group: P = 0.004; unsuitable group: P = 0.001).

CONCLUSIONS

Atrial resynchronisation therapy is effective in the long term management of drug-resistant AF in patients unsuitable for LA ablation, leading to significant reductions in symptoms, AF duration, admissions and AAD.

Optimizing the management of atrial fibrillation: focus on current guidelines and the impact of new agents on future recommendations

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in everyday clinical practice. It affects ~2.3 million individuals in the United States, and the prevalence is expected to increase ~2.5-fold over the next 40 years. Atrial fibrillation accounts for more than 2 million hospitalizations each year and contributes to nearly 67 000 deaths. Our understanding of the pathophysiology of AF has increased dramatically over the past few decades. Recent treatment guidelines have heightened our awareness of the challenges involved in the treatment of AF and provided useful recommendations for its diagnosis and management. Because AF is usually associated with multiple comorbid conditions, greater emphasis must be placed on individualizing treatment. This review focuses on current treatment guidelines for patients with AF, assessing the benefits and shortcomings of current pharmacologic options and discussing new agents and trials that may provide better opportunities to improve and individualize patient management.

Electrophysiological characteristics associated with symptoms in pacemaker patients with paroxysmal atrial fibrillation

PURPOSE

The purpose of this study is to identify the electrophysiological factors affecting symptoms in paroxysmal atrial fibrillation (PAF) using patients with paroxysmal atrial fibrillation and pacemakers with advanced atrial fibrillation (AF) diagnostics.

METHODS

Seventy-nine patients (age 71.0 +/- 8.2, 54.4% male) with symptomatic PAF and AF burden of 1% to 50% with DDDRP pacemakers implanted were assessed for 6 months. Patients recorded symptom onset and duration and these were correlated with device-derived electrophysiological data.

RESULTS

Of 2,638 AF episodes, 333 were symptomatic and 2,305 asymptomatic, with 194 non-atrial tachyarrhythmia symptomatic episodes giving a sensitivity of 12.6% and a positive predictive value of 63.2% for specific AF symptoms. Symptomatic AF episodes were 3.8 times more common diurnally than nocturnally (p < 0.001). Diurnally, symptomatic AF was significantly associated with a shorter AF cycle length (CL; p = 0.04), faster ventricular rate (p = 0.004), shorter PR interval (p < 0.001), faster preceding heart rate (p = 0.001) and increased early recurrence of AF (p < 0.04). Nocturnally, a significantly longer AF CL (p = 0.04) and PR interval (p < 0.001) prior to AF onset predicted symptomatic AF.

CONCLUSIONS

Symptoms in PAF are predicted by changes in AF episode duration, ventricular rate during AF, preceding sinus heart rate, AV nodal conduction and AF cycle length but not ventricular irregularity. Excess diurnal sympathetic tone and excess nocturnal vagal tone predispose to symptomatic PAF. These findings may have relevance for therapies for symptom control of PAF.

Incidence of Atrial Arrhythmias Detected by Permanent Pacemakers (PPM) Post-Pulmonary Vein Antrum Isolation (PVAI) for Atrial Fibrillation (AF): Correlation with Symptomatic Recurrence

BACKGROUND

Studies examining AF recurrences post-PVAI base recurrence on patient reporting of symptoms. However, whether asymptomatic recurrences are common is not well known.

OBJECTIVE

To assess the incidence of atrial tachycardia/fibrillation post-PVAI as detected by a PPM and whether these recurrences correlate to symptomatic recurrence.

METHODS

Eighty-six consecutive patients with symptomatic AF and PPMs with programmable mode-switch capability underwent PVAI. Mode switching was programmed post-PVAI to occur at an atrial-sensed rate of >170 bpm. Patients were followed with clinic visits, ECG, and PPM interrogation at 1, 3, 6, and 9 months post-PVAI. The number and duration of mode-switching episodes (MSEs) were recorded at each visit and is presented as median (interquartile range).

RESULTS

The patients (age 57 +/- 8 years, EF 54 +/- 10%) had paroxysmal (65%) and persistent (35%) AF pre-PVAI. Sensing, pacing, and lead function were normal for all PPMs at follow-up. Of the 86 patients, 20 (23%) had AF recurrence based on symptoms. All 20 of these patients had appropriate MSEs detected. Of the 66 patients without symptomatic recurrence, 21 (32%) had MSEs detected. In 19 of these patients, MSEs were few in number, compared with patients with symptomatic recurrence (16 [4-256] vs 401 [151-2,470], P < 0.01). The durations were all <60 seconds. All of these nonsustained MSEs occurred within the first 3 months post-PVAI, gradually decreasing over time. The other 2 of 21 remaining patients had numerous (1,343 [857-1,390]) and sustained (18 +/- 12 minutes) MSEs that also persisted beyond 3 months (1 beyond 6 months). Therefore, the incidence of numerous, sustained MSEs in asymptomatic patients post-PVAI was 2 of 66 (3%).

CONCLUSIONS

Detection of atrial tachyarrhythmias by a PPM occurred in 30% of patients without symptomatic AF recurrence. Most of these episodes were <60 seconds and waned within 3 months. Sustained, asymptomatic episodes were uncommon.

Self-limited bursts of atrial fibrillation following successful cardioversion

BACKGROUND

To evaluate if self-limited episodes of atrial fibrillation after DC cardioversion predict recurrence of persistent atrial fibrillation. To evaluate the incidence and duration of such episodes as well as their change over time.

METHODS

Consecutive patients with persistent atrial fibrillation, scheduled for direct current cardioversion were prospectively included in the study. Ambulatory ECG Holter monitoring (24 h) was performed one, three and 6 weeks after successful cardioversion.

RESULTS

A total of 84 patients were prospectively included in the study. Sinus rhythm was restored in 74 patients (88%). At 6 weeks of follow-up 40 patients out of 74 (54%) had sinus rhythm, and 34 patients (46%) had relapsed into persistent atrial fibrillation. Eight out of these 34 patients (24%) had bursts of atrial fibrillation at their first Holter recording, compared to 12 patients out of 40 (30%) in sinus rhythm at 6 weeks (p>0.05). On the first, second and third Holter recording 21 patients out of 51 (41%), 21 patients out of 43 (49%) and 15 out of 40 patients (38%) had self-limited bursts of atrial fibrillation, respectively. The incidence or duration of episodes did not vary over time during the 6 weeks of follow-up.

CONCLUSION

In patients successfully converted to sinus rhythm self-limited bursts of atrial fibrillation do not predict recurrence of persistent atrial fibrillation during 6 weeks of follow up. Brief self-limited episodes of atrial fibrillation are common, and the incidence and duration of such episodes are constant during a 6 weeks period after DC cardioversion.

The Epidemiology of Atrial Fibrillation in Elderly Persons: The Tip of the Iceberg

Atrial fibrillation is the most common clinically relevant arrhythmia and preferentially afflicts elderly persons, especially persons aged >/=75 years, with associated complications of ischemic stroke and other adverse outcomes. More than 2.2 million Americans currently have atrial fibrillation, and this number is expected to increase by at least 2.5-fold over the next 50 years. With the aging of the US and international populations, as well as the rising prevalence of clinical risk factors, the incidence and prevalence of atrial fibrillation are rising rapidly. While improved adherence to existing risk-based therapies can reduce thromboembolic complications in elderly persons, additional research is needed to determine novel approaches to prevent the initial development of atrial fibrillation in order to decrease the individual and public health burden of this condition.

Asymptomatic atrial fibrillation

Atrial fibrillation (AF) is a significant cause of morbidity and health care expenditures. Patients with AF suffer a variety of symptoms including chest pain, palpitations, shortness of breath, and fatigue. Some patients have no symptoms, a condition referred to as asymptomatic or "silent" AF. Asymptomatic AF has significant clinical implications. Patients with unrecognized AF may present with devastating thromboembolic consequences or a tachycardia-mediated cardiomyopathy. The incidence of asymptomatic AF is greater than previously perceived. This manuscript provides an overview of the clinical entity of asymptomatic AF including the epidemiology, clinical significance, and the implications it has on the daily management of patients suffering from AF.

Effect of C-reactive protein reduction on paroxysmal atrial fibrillation

BACKGROUND

C-reactive protein (CRP) lowering is associated with a reduction in recurrent and permanent atrial fibrillation. This study sought to determine whether CRP lowering also results in a reduction of paroxysmal atrial fibrillation (PAF) during daily life.

METHODS AND RESULTS

We enrolled 80 patients with proven PAF, CRP between 0.8 and 13 mg/L, and at least 1 episode of PAF on ambulatory electrocardiographic monitoring. Forty patients were randomized to placebo (placebo group) and 40 to atorvastatin (treatment group). Plasma CRP levels and ambulatory monitoring were repeated after 4 to 6 months of therapy. The 2 groups were comparable with respect to baseline characteristics, number of episodes of PAF, and baseline plasma CRP levels. The treatment group had lower median CRP levels at study end and experienced a significant reduction in the number of episodes of PAF compared with the placebo group. Paroxysmal atrial fibrillation was completely resolved in 26 (65%) of 40 patients in the treatment group versus 4 (10%) of 40 in the placebo group. The treatment group exhibited a highly significant reduction in PAF (P < .001). By logistic regression, treatment with atorvastatin was an independent predictor of PAF resolution.

CONCLUSIONS

C-reactive protein lowering with atorvastatin appears to be effective in eliminating PAF during daily life in a significant proportion of patients.

Asymptomatic atrial fibrillation: demographic features and prognostic information from the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study

BACKGROUND

Atrial fibrillation (AF) may occur without symptoms. Little is known about demographic features and prognostic information in patients with asymptomatic AF.

METHODS

In the AFFIRM study, 4060 patients were randomized to either rhythm or rate control. At baseline, patients were identified as asymptomatic if they answered "no" to a 15-item questionnaire related to cardiac symptoms during AF in the 6 months before study entry.

RESULTS

There were 481 (12%) asymptomatic patients at baseline. Compared with symptomatic patients, asymptomatic patients were more often men and had a lower incidence of coronary artery disease and congestive heart failure, but had more cerebrovascular events. Asymptomatic patients had a longer duration of AF, a lower maximum heart rate, and better left ventricular function. They received fewer cardiac medications and fewer therapies to maintain sinus rhythm. At 5 years, there was a trend for better survival in asymptomatic patients (81% vs 77%, P = .058), and they were more likely to be free from disabling stroke or anoxic encephalopathy, major bleeding, and cardiac arrest (79% vs 67%, P = .024). However, mortality and major events were similar after correction for baseline differences.

CONCLUSIONS

Patients with asymptomatic AF have less serious heart disease but more cerebrovascular disease. Asymptomatic patients receive different therapies than symptomatic patients. However, the absence of symptoms and the differences in treatment does not confer a more favorable prognosis when differences in baseline clinical parameters are considered. Anticoagulation should be considered in these patients.

Accuracy of Mode Switch Algorithms for Detection of Atrial Tachyarrhythmias

INTRODUCTION

In patients with permanent pacemakers, mode switching events often are interpreted as surrogate markers for atrial tachyarrhythmias. The aim of this study was to determine the accuracy of automatic mode switching algorithms in patients with permanent pacemakers for the diagnosis of atrial tachyarrhythmias.

METHODS AND RESULTS

Forty patients with tachycardia-bradycardia syndrome and Medtronic Thera or Kappa 700 permanent pacemakers underwent Holter monitoring. Date, time of onset, and duration of each mode switch episode as recorded by the pacemaker and each atrial tachyarrhythmia episode as recorded by the Holter monitor were compared. Sixteen patients had a total of 54 atrial tachyarrhythmias documented on Holter monitoring (47 atrial fibrillation, 7 atrial flutter). Comparison of Holter data with pacemaker interrogation demonstrated that 53 (98.1%) of 54 atrial tachyarrhythmia episodes resulted in mode switching with one 13-second episode of mode switching during sinus rhythm. The sensitivity and specificity of mode switching for the duration of atrial tachyarrhythmias were 98.1% and 100%, respectively. The algorithms detected 98.9% of the total duration of atrial fibrillation and 96.4% of the total duration of atrial flutter.

CONCLUSION

In patients with tachycardia-bradycardia syndrome and permanent pacemakers having these mode switching algorithms, mode switching events are reliable surrogate markers for atrial tachyarrhythmias. Therefore, mode switching may serve as a valuable tool for clinical decision making and further research into the natural history and burden of atrial tachyarrhythmias.

Progressive Nature of Paroxysmal Atrial Fibrillation-Observations From a 14-Year Follow-up Study-

BACKGROUND

Atrial fibrillation (AF) is believed to occur first as paroxysmal, then be gradually perpetuated, and finally become chronic as the end result. However, this presumed clinical course has not been well confirmed.

METHODS AND RESULTS

The clinical course of recurrent paroxysmal AF (PAF) from its onset was examined in 171 patients (mean follow-up period: 14.1+/-8.1 years). This study population consisted of patients with no structural heart disease (n=88), ischemic heart disease (n=28), dilated or hypertrophic cardiomyopathy (n=17), valvular heart disease (n=35) or other cardiac diseases. The mean age at the onset of AF was 58.3 +/-11.8 years old. During the mean follow-up period of 14.1 years, PAF eventually developed into its chronic form in 132 patients under conventional antiarrhythmic therapy (77.2%, 5.5% of patients per year). The independent factors for early development into chronic AF were aging (hazard ratio (HR) 1.27 per 10 years, 95% confidence interval (CI) 1.06-1.47)), dilated left atrium (HR 1.39 per 10 mm, 95% CI 1.11-1.69), myocardial infarction (HR 2.33, 95% CI 1.13-4.81), and valvular diseases (HR 2.29, 95% CI 1.22-4.30).

CONCLUSIONS

The present long-term observations definitely and quantitatively revealed the progressive nature of PAF.

Asymptomatic or "silent" atrial fibrillation: frequency in untreated patients and patients receiving azimilide

BACKGROUND

Asymptomatic, or "silent" atrial fibrillation could increase the risk of stroke. Little is known about the frequency of asymptomatic atrial fibrillation in patients who also have symptomatic atrial fibrillation; similarly, little is known about the effect of antiarrhythmic drug therapy on asymptomatic atrial fibrillation.

METHODS AND RESULTS

Patients in sinus rhythm with a history of symptomatic atrial fibrillation or atrial flutter received placebo or azimilide (35 to 125 mg) once daily for 6 or 9 months in 4 similar double-blind trials. The end point was the first recurrence of a symptomatic ECG-documented supraventricular arrhythmia. Routine transtelephonic electrocardiograms, in the absence of symptoms, were recorded for 30 seconds every 2 weeks until patients completed follow-up or documented a symptomatic supraventricular arrhythmia. Of the 1380 patients, 489 received placebo. Among these patients receiving placebo, 303 transmitted at least one routine ECG while asymptomatic. Asymptomatic atrial fibrillation was recorded in 50 (17%) within 6 months and before recurrence of symptomatic supraventricular arrhythmia. In the 3 trials evaluating azimilide in therapeutic doses (100 and 125 mg), asymptomatic atrial fibrillation occurred in 49 of 382 (13%) receiving azimilide and 43 of 233 (18%) receiving placebo. Although drug effect on time to first asymptomatic event was not statistically significant (hazard ratio, 0.70; P=0.09), there was a 40% reduction in asymptomatic atrial fibrillation on azimilide compared with placebo (P=0.03) when repeated observations were considered.

CONCLUSIONS

Asymptomatic atrial fibrillation is common in untreated patients with a history of symptomatic atrial fibrillation (and is likely underestimated by this analysis). Azimilide may reduce the occurrence of this silent arrhythmia.

Current management of symptomatic atrial fibrillation

Atrial fibrillation (AF) is the commonest arrhythmia. It presents in distinct patterns of paroxysmal, persistent and chronic AF, and patient management aims differ according to the pattern. In paroxysmal AF, drug treatment with beta-blockers, class Ic and class III agents reduce the frequency and duration of episodes. In persistent AF (recent onset, non-paroxysmal), early cardioversion with either pharmacological agents or by direct current (DC) cardioversion should be actively considered, in those patients who are suitable. Patients most likely to cardiovert and remain in sinus rhythm include those with duration of AF of <1 year, an acute reversible cause, left atrial diameter <50 mm and good left ventricular function on echocardiography. Recent data show that maintenance of sinus rhythm after successful cardioversion is enhanced by the use of class III drugs including amiodarone and dofetilide. In chronic or permanent AF, management is aimed at controlling the ventricular rate response with combinations of digoxin, beta-blockers and calcium antagonists with atrio-ventricular nodal activity (diltiazem and verapamil). There is some debate about the prognostic significance of AF. Certainly AF is associated with an excess mortality but this is largely accounted for by its association with serious intrinsic heart disease and the thrombo-embolic complications of the arrhythmia. Atrial fibrillation is a common default arrhythmia for the sick heart.

Second line pharmacological management of paroxysmal and persistent atrial fibrillation in france: a cost analysis

OBJECTIVES

Despite optimal pharmacological treatment a large proportion of patients with atrial fibrillation (Afib) are not arrhythmia-free, and remain at risk for complications such as stroke and cardiac morbidity. If first-line treatment fails, most patients receive second-line pharmacological treatment. The emergence of new technologies aimed at restoring and maintaining sinus rhythm, such as catheter ablation techniques, has increased the interest in the economic aspects of second-line pharmacological treatment. The objective was therefore to calculate the 5-year direct medical costs of second-line pharmacological management of paroxysmal and persistent Afib in France.

METHODS

The analysis was based on clinical and economic literature and the input of cardiologists-electrophysiologists. The analysis included probabilities of stroke, sudden cardiac death, other cardiac and noncardiac death, direct medical costs of drugs, follow-up and complications from the healthcare payer's perspective. Included treatment strategies were (1) rhythm control with class Ic and III antiarrhythmics and (2) rate control, consisting of digoxin combined with a beta-blocker or calcium antagonist. Both strategies included aspirin or anticoagulation therapy.

RESULTS

The average total 5-year cost of Afib was 16,539 Euro (FF 108,486) per patient. The result was stable to sensitivity analysis on incidence of stroke and type of stroke prevention. The main cost drivers were follow-up visits and hospitalizations and the cost of congestive heart failure. Both items being subject to some variation, they were submitted to sensitivity analysis showing minimal 5-year costs still over 14,483 Euro (FF 95,000).

CONCLUSIONS

Afib management places high demands on medical resources mainly through its complications and comorbidity.

Clinical relevance of silent atrial fibrillation: prevalence, prognosis, quality of life, and management

Although first described about 100yr ago, atrial fibrillation (AF) is now recognized as the most common of all arrhythmias. It has a substantial morbidity and presents a considerable health care burden. Improved diagnosis and an ageing population with an increased likelihood of underlying cardiac disease results in AF in more than 1% of population. AF is associated with an approximately two-fold increase in mortality, largely due to stroke which occurs at an annual rate of 5-7%. Another risk to survival is heart failure, which is aggravated by poor control of the ventricular rate during AF. Usually AF is associated with a variety of symptoms: palpitations, dyspnea, chest discomfort, fatigue, dizziness, and syncope. Paroxysmal AF is likely to be symptomatic and frequently presents with specific symptoms, while permanent AF is usually associated with less specific symptoms. However, in at least one third of patients, no obvious symptoms or noticeable degradation of quality of life are observed. This asymptomatic, or silent, AF is diagnosed incidentally during routine physical examinations, pre-operative assessments or population surveys. Recently, a very large incidence of generally short paroxysms of AF has been seen in patients with implantable pacemakers or defibrillators and these arrhythmias are often silent. Pharmacological suppression of arrhythmia may be associated with a conversion from a symptomatic to an asymptomatic form of AF. Holter monitoring and transtelephonic monitoring studies have demonstrated that asymptomatic episodes of AF exceed symptomatic paroxysms by twelve-fold or more. Although symptoms may not stem directly from AF, the risk of complications is probably the same for symptomatic and asymptomatic patients. AF is found incidentally in about 25% of admissions for a stroke. Studies in patients with little or no awareness of their arrhythmia condition indicate that unrecognized and untreated AF may cause congestive heart failure. In patients with coronary bypass, AF may not only represent risk for immediate postoperative morbidity and increase hospital resource utilization, but being unrecognized, may produce a significant impact on long-term survival and quality of life. Although silent AF merits consideration for anticoagulation and rate control therapy according to standard criteria, whether antiarrhythmic therapy is relevant in this condition remains unclear.

An open label, randomised, crossover study comparing sotalol and atenolol in the treatment of symptomatic paroxysmal atrial fibrillation

OBJECTIVE

To compare sotalol and atenolol in the treatment of symptomatic paroxysmal atrial fibrillation.

DESIGN

Prospective, randomised, open label, crossover study.

SETTING

University hospital.

PATIENTS

47 subjects aged over 50 years were recruited from the hospital outpatient department following ECG documentation of paroxysmal atrial fibrillation that coincided with symptoms. Six patients withdrew and 41 completed the trial.

INTERVENTIONS

Patients were randomised to one month's treatment with sotalol 80 mg twice daily or atenolol 50 mg once daily. Treatment arms were then crossed over. Patients underwent 72 hour Holter monitoring before randomisation and repeat studies were carried out at the end of both treatment periods. Symptom assessments were completed using linear analogue scales and the Nottingham health profile.

MAIN OUTCOME MEASURE

Frequency of paroxysmal atrial fibrillation; secondary outcome measures included average and total duration of paroxysmal atrial fibrillation, total ectopic count, and symptom assessments.

RESULTS

A reduction in the number and duration of episodes of paroxysmal atrial fibrillation was noted following treatment with sotalol and atenolol. There was no difference in frequency of paroxysmal atrial fibrillation during treatment with sotalol or atenolol (median difference 0; 95% confidence interval (CI) 0 to 1; p = 0.47). There was no difference in total duration of paroxysmal atrial fibrillation (median difference 0 min; 95% CI -1 to 2; p = 0. 51) or in average duration (median difference 0 min; 95% CI 0 to 1; p = 0.31). No difference was found in total ectopic count between sotalol and atenolol (median difference -123; 95% CI -362 to 135; p = 0.14). Treatments were equally tolerated with no difference in linear analogue scores for symptoms of paroxysmal atrial fibrillation (median difference -5; 95% CI -20 to 5; p = 0.26) or in all categories of the Nottingham health profile.

CONCLUSIONS

No difference was found in terms of ECG or symptomatic control of paroxysmal atrial fibrillation between prescribing sotalol 80 mg twice daily and atenolol 50 mg once daily. There was an improvement in paroxysmal atrial fibrillation from baseline following treatment with either sotalol or atenolol.