Practice Update: Cardiology

ESC 2017 13

ESC 2017: Ablation of Atrial Fibrillation Improves Quality of Life More than Drugs – CAPTAF Trial Ablation of atrial fibrillation has been shown to improve quality of life more than drugs, even though the reduction in atrial fibrillation burden did not differ significantly between treatments. T his conclusion, based on results of the multicenter, prospective, rand- omized Catheter Ablation compared heart failure, left atrial and ventricular func- tion and diameters, exercise capacity, health care economics, rhythm, atrial fibrillation bur- den, successful vs failed treatment, safety, and “cross-overs” over time.

CAPTAF included 155 patients with symp- tomatic atrial fibrillation who had failed one drug for either rate or rhythm control. Patients suffered at least one episode of atrial fibrillation documented on electro- cardiography in the previous 12 months. At least one symptomatic paroxysmal episode had occurred in the previous 2 months, or at least two symptomatic episodes of persistent atrial fibrillation necessitating cardioversion in the previous 12 months. Patients received an implantable cardiac monitor for a 2-month run-in period, then were randomized to ablation with pulmo- nary vein isolation or antiarrhythmic drug therapy with adequate dosages according to guidelines. The primary endpoint was the change in general health, as measured by the Short Form 36-item health survey, from base- line to 12 months. Secondary endpoints included quality of life (by Short Form 36 and EuroQol 5 Dimensions), symptoms, European Heart Rhythm Association Symptom Classification, burden of atrial fibrillation, and safety. “We measured the burden of atrial fibril- lation before randomization so we got a good idea of burden at baseline,” Dr. Blom- ström-Lundqvist said. The main secondary endpoints were mor- bidity and mortality as composite outcome, cardiovascular hospitalization, symptoms,

with optimized Pharmacological Therapy for Atrial Fibrillation (CAPTAF) trial, was pre- sented at the 2017 European Society of Cardiology (ESC) Congress, from August 26–30. Carina Blomström-Lundqvist, MD, PhD, of the University of Uppsala, Sweden, explained that previous randomized trials have reported that pulmonary vein isola- tion is more effective in preventing atrial fibrillation than antiarrhythmic drugs. None of these trials, however, employed contin- uous cardiac rhythm monitoring, so effects on the burden of atrial fibrillation could not be assessed reliably. Until now, no trial of ablation of atrial fibril- lation has employed quality of life as the primary endpoint even though the main indication for ablation of atrial fibrillation is symptom relief. “Instead,” Dr. Blom- ström-Lundqvist said, “30-s recurrences of atrial fibrillation have been used as the primary endpoint, hardly a relevant meas- ure of successful therapy.” The main purpose of the CAPTAF trial was to compare the treatment effects of abla- tion of atrial fibrillation and antiarrhythmic drugs using quality of life as the primary endpoint and an implantable cardiac moni- tor to assess the burden of atrial fibrillation.

“We tried to record silent atrial fibrillation via a patient log book. We got a record for the first year but in the second year, patients were reluctant to record these episodes. We haven’t analyzed these data yet.” After 12 months of follow-up, the primary endpoint of general health score had improved significantly more in the ablation group (mean change 11.0; 95% confidence interval 6.7–15.2) than in the drug group (mean change 3.1; 95% confidence interval –0.9–7.1), P = .0084. Furthermore, all qual- ity-of-life Short Form 36 subscales except for bodily pain and social functioning had improved significantly more in the ablation group than in the drug group. European Heart Rhythm Association symp- tom score improved significantly more from baseline to 12 months in the ablation group (from mean 3.0±0.7 to 1.6±0.8) than in the drug group (from mean 2.9±0.7 to 2.1±1.1; P = .0079). Reduction of burden in atrial fibrillation (that is, the proportion of time in atrial fibrilla- tion), obtained from the implantable cardiac monitor, was numerically larger in the abla- tion than in the drug group, but change from baseline did not reach statistical significance between treatment groups. The complication rate was comparable between treatment groups. Dr. Blomström-Lundqvist concluded, “Qual- ity of life should be the primary endpoint in future trials since the main indication for rhythm control is improvement.” She continued, “The lack of a statistically significant difference between treatment groups in the reduction in burden of atrial fibrillation suggests that other mechanisms may explain the better improvement of quality of life and symptoms achieved with pulmonary vein isolation compared to anti- arrhythmic drugs.” She added, “We confirmed that quality of life improved greatly with ablation vs anti- arrhythmic drugs. We think it’s because of side effects of antiarrhythmic drugs, but we have not determined this definitively.”

PracticeUpdate Editorial Team

© ESC Congress 2017 – European Society of Cardiology

VOL. 2 • NO. 2 • 2017