From the Emergency Department Directly to Ablation of Atrial Fibrillation - Study - The "EMERGE-Cryo-Study"

As stated in the current guidelines, the prevalence of AF tripled over the last 30 years and further progress is expected. AF is associated with increased mortality and morbidity. Approximately 70% of the patients who are hospitalized for AF are admitted through the emergency department. The steady increase of AF-related visits at the emergency departments therefore lead to a high number of hospitalizations. The direct costs of AF already amount to approximately 1% of total healthcare spending, driven by AF-related complications (e.g. stroke) and treatment costs (e.g. hospitalizations). These costs will increase dramatically unless AF is prevented and treated in a timely and effective manner.

Catheter ablation therapy has been proven to be safe and effective for the treatment of paroxysmal and persistent AF and is now standard in AF therapy. Several trials have shown that catheter ablation of AF is superior to antiarrhythmic drug therapy. As evidenced by the FIRE & ICE trial, cryoballoon ablation is non-inferior to the former goldstandard of radiofrequency current (RFC) energy. Importantly, it has been reported that cryoballoon ablation was associated with a reduction in resource use and costs as compared to RFC ablation of AF. These cost savings persisted over multiple healthcare systems.

However, data on the optimal timing of AF ablation is scarce. While there is evidence that catheter ablation is highly efficient in delaying progression from paroxysmal to persistent AF, there are only few trials evaluating a strategy of early treatment of AF, regarding the patients' medical history (CRYO-FIRST, EARLY-AF). Another trial investigated the utilization of a multidisciplinary AF treatment pathway in patients presenting to the emergency department, which resulted in reduction of admission rate and hospital stays but did not include catheter ablation of AF. However, there is no scientific evidence on a strategy of early treatment of atrial fibrillation comparing anti-arrhythmic drug therapy to catheter ablation in the large number of patients presenting to the emergency departments.

A well-known limitation of many trials investigating catheter ablation of AF, can be found during the trials follow up after ablation, as detection of AF recurrences can be challenging. The sensitivity of detecting asymptomatic episodes with intermittent 24-hours ECG-monitoring is low. The Heart Rhythm Society and the European Heart Rhythm Society encourage continuous arrhythmia monitoring due to the greater sensitivity in detecting symptomatic and asymptomatic AF recurrences but also when assessing the overall AF burden. Additionally, in an era of digital revolution, the AFNET incorporated the use of wearables, smartphones, hand held-devices and health-related apps to new approaches of AF management.

To evaluate the efficacy and safety of an early rhythm control treatment of AF by catheter ablation with the cryoballoon with particular respect to arrhythmia recurrence, rehospitalisation, heart failure and health care costs in patients presenting to the emergency department due to AF, a prospective randomized study is necessary.