Atrial fibrillation in Europe: state of the state in disease management!

This editorial refers to ‘Prognosis and treatment of atrial fibrillation patients by European cardiologists: One year follow-up of the EURObservational Research Programme–Atrial Fibrillation General Registry Pilot Phase (EORP-AF Pilot registry)’†, by G.Y. Lip et al., on page 3365. Atrial fibrillation (AF) is the most common sustained arrhythmia, with an estimated prevalence of 6 million among all Europeans.1 This places a huge public health burden in terms of morbidity, mortality, and cost issues.2,3 The disease continues to grow to epidemic proportions as the aged population increases, with a projected doubling of the disease in the next 50 years.1 Despite advances in our understanding of the disease process, patient awareness, technology, and therapeutic strategies, the incidence of AF-related stroke continues to rise.4 The EURObservational Research Programme–Atrial Fibrillation General Registry Pilot Phase (EORP-AF Pilot registry) has now been published, where data are presented on 1-year follow-up of 3319 patients included in the registry that were obtained from 67 centres in nine European countries.5 The EORP-AF Pilot general registry is an ambitious effort and was designed as a long-term cohort. As stated by the authors, the main objectives of the follow-up of the EORP-AF registry are stated as follows: (i) to obtain contemporary information on the occurrence of AF-related complications in Europe; (ii) to assess whether the diagnostic work-up of AF complies with current European Society of Cardiology (ESC) guidelines (2010 guidelines and the 2012 focused update) and the impact on outcomes; (iii) to evaluate appropriateness of treatment in the different subsets of AF in relation to the current guidelines on AF, and the impact on outcomes; (iv) to describe the use of new antiarrhythmic therapy options such as catheter ablation and newly available antiarrhythmic drugs, and the impact on outcomes; and others. They are partly successful in obtaining at least some pieces of this information during a 1-year follow-up. Large registries such as this one are vital to understanding the differences in symptomatology, management strategies, and mortality and morbidity rates. While this seems to be a reasonable sample of the state of AF management from nine representative countries of in Europe, it may still not represent all AF patients in the continent.6 This obviously does not capture the practice patterns of general practitioners who treat AF patients and those of other countries that were not represented in the registry. The registry commenced in 2012, and 1-year data are represented here. It was interesting to note that 70% of patients were symptomatic at enrolment, of whom only 23% were noted to be symptomatic at 1 year.7 The mitigation of symptoms with a minimal rhythm control effort ( < 20% total) was rather impressive. This opens up the discussion regarding whether it is related to a very effective rate control strategy or is merely an issue of data capture from the patients. Contrary to our assumptions here, there seems to be a significant rate of rehospitalizations with poor ventricular rate control and heart failure exacerbation. The overall rhythm control effort was < 20%, with minimal use of antiarrhythmic drugs, cardioversion, and catheter-based ablation therapies. The gap between a very high symptom burden and significant under-utilization of rhythm control strategies does not seem to be filled well by rate control strategies alone. Beta-blockers and digoxin seem to be the favourite recipe. Calcium channel blockers seem to be not on the formulary in the European markets. It is evident from the numbers that ∼80% of the AF patient cohort were treated with some form of rate control therapy, and close to 80% were also on antithrombotic therapy, with an impressive reduction in symptom burden but no significant improvement in rates of hospitalization related to tachyarrhythmias, congestive heart failure, or risk of embolic events and mortality. There is a high level of success with the initiation and maintenance of oral antithrombotic therapy at 1 year, but the time in the therapeutic range is not well documented. The above rates are higher that what has previously been reported and may represent a positive change perhaps brought about by heightened awareness of physicians and patients regarding AF.8 The study also tells us that while novel anticoagulation agents were only prescribed in 10%, their use has increased over the last year. The overall time in the therapeutic range will remain the true marker for the effectiveness of anticoagulation efforts. The higher stroke and systemic embolic incidence definitely reflects the cracks in the system. The high incidence of heart failure is probably a direct reflection of poor rate control. It would have been good to know what percentage of these chronic heart failure (CHF) episodes had happened in patients with a known history of CHF. It is safe to assume that this will be a relatively large percentage since AF and CHF go hand in glove. It would have been very helpful to know if atrioventricular node ablation was offered or performed in any of these patients as a more effective rate control therapy. Catheter ablation has made significant strides in its ability to mitigate symptoms, and improve the overall quality of life, strokes, and dementia. All the advances in the diagnostic and therapeutic tools have improved the overall success of this procedure in the last decade. Yet it is interesting to see a paltry 4% of patients being referred for AF ablation. These rates are not greatly different from the rates reported in a survey across Europe 10 years ago in 20059 when non-irrigated catheters were used, procedure times were longer, and recurrence rates and complication rates were higher.10 One would expect that catheter ablation would have been used as a therapeutic strategy more frequently than what the data suggest. It will be interesting to explore further the underlying reasons for underutilization of this treatment strategy. What factors determine this phenomenon—is it the availability of skilled operators, access to care, or general lack of awareness amongst the referring doctors? The high rates of strokes and systemic thrombo-embolization rates still remain of great concern. Is it over-reliance on the effectiveness of systemic oral anticoagulation along with a widespread adaptation of a non-rhythm control strategy that led to this? Maybe it is time for a more aggressive rhythm control strategy with a combination of antiarrythmic drugs and appropriately individualized catheter ablation. The data once again confirm the high mortality rates associated with AF (5.7%). The majority of these deaths were related to heart failure. While patients with heart failure represent a sicker population, recent data suggest higher mortality with use of digoxin in AF.11 While the use of digoxin was high in this cohort, we assume this did not predict the risk of death as this was not a predictor in univariate or multivariate analysis. Given the high mortality and re-hospitalization rates from heart failure in this population with AF that adopted a predominantly rate control strategy, it may be prudent to consider a rhythm control strategy whereby the incidence of heart failure and re-hospitalizations from tachyarrhythmias may be reduced. Focus on patient awareness programmes, and early recognition and intervention will go a long way in improving the overall disease management of patients with AF. The study overall provides several good insights. First, the use of anticoagulation agents is shown to be remarkably higher than that reported in previous studies and deserves applause, although the translated benefit of reduced ischaemic stroke is yet to be demonstrated. Secondly, overall assessment of symptoms may not be very accurate. Thirdly, a rate control strategy with antithrombotic therapy seems to be the most common treatment strategy; however, the effectiveness of this approach is called into question by the results. Even though randomized trials such as CABANA are currently being conducted looking at AF ablation as a first-line therapy,12 general practice patterns still demonstrate a low rate of AF catheter ablation overall, if not as a first-line approach. With the recently published data on increased risk of mortality with digoxin, the outcomes and change in practice patterns at follow-up will be worth looking at. As the incidence of AF rises to epidemic proportions, the real challenge lies ahead for healthcare delivery systems in providing appropriate and timely intervention in improving symptoms, morbidity, and mortality. It requires a multipronged approach that should actively engage all of the stake-holders in a much bigger way. Conflict of interest: none declared.