Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia occurring in about 1 % of the general population (10 % of all people aged > 80 years are suffering from AF) [1]. Over 6 million Europeans suffer from this arrhythmia and its prevalence is estimated to increase significantly within the next decades as the population ages and manifests more comorbidities [2, 3].

AF is associated with a doubling of overall mortality and a fivefold increased risk of stroke [4, 5]. Clinical symptoms may include palpitations, dyspnoea or syncopes with significant impairment of quality of life (QoL). On the other hand AF can also occur unnoticed unless incidentally found or until complications occur [2, 6]. A number of newer investigations, which used a non-interventional design similar to ours, showed substantially compromised QoL in AF patients [7−12].

Dronedarone is an antiarrhythmic drug which has a benzofuran moiety as amiodarone but does not possess the iodine part affecting thyroid function [13]. Due to differences such as a methyl sulphonyl group the lipophilicity of the new agent compared with amiodarone was reduced and its plasma half-life substantially shortened thought to reduce organ toxicity due to cumulative effects.

The drug has been launched in 2010 in Germany under the brand name Multaq®. Based on the results of new trials and pharmacovigilance reports its labelling has been amended several times. According to the current summary of product characteristics, Multaq® is indicated for the maintenance of sinus rhythm after successful cardioversion in adult clinically stable patients with paroxysmal or persistent AF [14]. Due to its safety profile, the agent should only be prescribed after alternative treatment options have been considered. Multaq® should not be given to patients with left ventricular systolic dysfunction or to patients with current or previous episodes of heart failure [14]. Careful monitoring during dronedarone administration is recommended with regular assessment of cardiac, hepatic and pulmonary function.

While dronedarone has been extensively documented in the context of clinical studies [15], there is a paucity of data on the use under real life conditions, with the exception of a retrospective database analysis of all patients treated with the drug between 2010 and 2012 in Sweden [16]. The real life patient population often differs from patient cohorts in controlled clinical studies with regards to demographic characteristics, comorbidities and concomitant diseases. Data collected in non-interventional studies like IMPULS can complement the findings of pivotal studies. We aimed to collect such data, with particular focus on QoL.

A total of 161 office-based cardiologists, general practitioners and internists throughout Germany took part in this study.

To the best of our knowledge, the IMPULS study is the only prospective observational study that specifically documents the use of dronedarone under clinical practice conditions. Previous similar AF studies in Germany such as MOVE [21] or ATRIUM [22] were performed too early to accrue significant patient numbers.

IMPULS used similar inclusion criteria as the ATHENA study and focused on patients with AF who had additional risk factors for death [23]. In that study, patients in the dronedarone group had higher rates of bradycardia, QT-interval prolongation, nausea, diarrhoea, rash and an increased serum creatinine level than the placebo group, whereas rates of thyroid- and pulmonary-related adverse events were not significantly different between the two groups. Dronedarone reduced the incidence of hospitalisation due to cardiovascular events or death [23].

In our study, dronedarone was well-tolerated, and the reported adverse drug reactions were in line with current knowledge. The most frequently reported reason for drug withdrawal was recurrence of AF and therefore not related to safety per se. With respect to laboratory values, the rate of abnormal liver function tests was substantially higher in IMPULS (10.9 %) compared with ATHENA (0.5 %) which might be due to the fact that in the latter trial there were no scheduled hepatic tests. Conversely, in ATHENA an increase in serum creatinine was noted in 4.7 %, compared with 0 % in our study. A recent retrospective database analysis on all 4856 patients treated with dronedarone in Sweden during 2010–2012, i.e., before the implementation of restrictions in the labelling of the drug, showed that patients selected for treatment were low-risk and had lower mortality than expected from the general population, or than AF patients on other antiarrhythmic medication [16]. Further, the risk of incident liver disease was significantly lower among dronedarone patients than among other AF patients (HR 0.57; 95 % CI 0.34–0.92) [16].

It is important to represent the patient perspective in the management of AF [24]. Thus, the number of studies that reported QoL in AF has steadily increased in the last years. The instrument ‘typically used’ is the SF-36, but the SF-12 has also been shown to provide robust results in the Birmingham Atrial Fibrillation Treatment of the Aged study [25]. In IMPULS, two questionnaires were administered in a complimentary manner to assess QoL, namely the SF-12 and EQ-5D VAS as generic and the AF-QoL as disease-specific instrument [15, 16]. Generic instruments document general aspects of physical, mental or social functionality, which can similarly be compromised in diverse diseases, and can be compared across these diseases using the instruments. However, they are often less sensitive [19, 20] as health improvement and QoL instruments are often not represented by a generic tool sufficiently [26]. Disease-specific questionnaires such as the AF-QoL focus on typical aspects of the disease, which may be experienced subjectively very differently by patients.

As it has been performed in a similar setting (office-based physicians in Germany), the MOVE cross-sectional study is particularly useful to compare results [27]. On the 100-point VAS, the 3354 patients overall had a value of 68 ± 18 points (paroxysmal 70, persistent 68, permanent 66 points) and thus a lower value compared with IMPULS (66 at baseline, 74 at FU). As in MOVE, [27] QoL scores were slightly worse in women compared to men, for all types of AF. It was notable that during the FU of the study in IMPULS, QoL on all instruments was substantially improved with the greatest effect already at the first FU visit. The observed improvement of 11 points on the VAS corresponds to a clinical improvement of about one category in the European Heart Rhythm Association (EHRA) score (which is reported in four classes) and thus represents a significant effect [28]. This finding may be due to the clinical effect of dronedarone, but could also be an unspecific consequence of intensive care of patients in the context of this study.

In conclusion, in this contemporary study on the use of dronedarone under clinical practice various dimensions of QoL of patients with AF were improved in the long term. No previously unknown safety issues were identified.