Catheter ablation for atrial fibrillation

The findings were presented August 27 at ESC Congress 2012 by Dr Elena Arbelo from Hospital Clínic de Barcelona, Spain, a co-investigator of the study.

"Atrial fibrillation is the most frequent heart rhythm disorder and it represents a highly significant burden of disease and expenditure throughout the world," explained Dr Arbelo. "The currently available pharmacological therapies are not 100% effective, and they have secondary effects."

While symptoms remain the major reason for Afib ablation, patients also welcome a drug-free life-style. The principal ablation strategy is the isolation of the pulmonary veins with additional linear and/or fragmented electrogram ablation in 10-20% of patients.

The AFib Ablation Pilot Study, the first registry to evaluate the day-to-day diagnostic and therapeutic processes of AFib ablation in Europe, is a prospective, multicentre, 12-month observational study which recruited 1410 patients from 10 different European countries (Belgium, Czech Republic, Denmark, France, Germany, Greece, Italy, Netherlands, Poland, Spain).

Results from the in-hospital phase of the study were presented ESC Congress 2011 and showed that two-thirds of patients having catheter ablation have paroxysmal AFib, and up to 40% have no apparent underlying cardiac disorder.

Now, results from the 12-month follow-up visit period provide further details of real-life outcomes:

* Over the study period 77% of patients visited the clinic in person for review; however, at the 12-month follow-up 42% of the evaluations were by telephone.

* Over half of the study population became asymptomatic after the ablation procedure (symptoms were present in 90% of patients at baseline).

* 76% of patients had a periodical ECG to document arrhythmia recurrence, and only 50% of patients had Holter monitoring.

* One-third of patients had a transthoracic echocardiogram during follow-up. Other tests such as cardiac CT or MRI were rare.

* Almost 20% of patients had a second ablation procedure.

* At 12 months around half of the study population were taking anticoagulants and 43% antiarrhythmic drugs. At discharge, 97% of patients had been prescribed anticoagulants and 67% antiarrhythmic medication.

* The procedure was considered successful in 74% of patients, meaning no documented arrhythmias after a 3-month blanking period. However, just over 50% of patients were still taking antiarrhythmic drugs.

* Complications during the first year after the ablation were infrequent (2.6%), and mainly related to cerebrovascular events (0.54%) or vascular injuries (0.71%). There were four deaths: one secondary to hemorrhagic stroke, one for a non-cardiovascular cause and two of unknown origin.

"The information obtained by the registry reflects everyday practice across Europe," said Dr Arbelo. "It is remarkable to see how most hospitals are evaluating the results of catheter ablation in a much more practical way than what is recommended for clinical trials, basing it mainly on periodical electrocardiograms and occasional Holter monitoring." She added that the results offer no clear definition how a successful procedure is defined -- by abolition of symptoms or the absence of arrhythmias without antiarrhythmic drugs.

Commenting on the first-year information derived from the pilot registry, Dr Arbelo said: "Atrial fibrillation is a major cardiovascular challenge in modern society and its medical and socioeconomic impact is expected to rise over the coming years. The AFib Ablation Registry provides an exceptional insight into the impact which catheter ablation may have in the management of patients with this arrhythmia."