Effect of Catheter Ablation vs Antiarrhythmic Medication on Quality of Life in Patients With Atrial Fibrillation: The CAPTAF Randomized Clinical Trial

Abstract

Importance: Quality of life is not a standard primary outcome in ablation trials, even though symptoms drive the indication.

Objective: To assess quality of life with catheter ablation vs antiarrhythmic medication at 12 months in patients with atrial fibrillation.

Design, setting, and participants: Randomized clinical trial at 4 university hospitals in Sweden and 1 in Finland of 155 patients aged 30-70 years with more than 6 months of atrial fibrillation and treatment failure with 1 antiarrhythmic drug or β-blocker, with 4-year follow-up. Study dates were July 2008-September 2017. Major exclusions were ejection fraction <35%, left atrial diameter >60 mm, ventricular pacing dependency, and previous ablation.

Interventions: Pulmonary vein isolation ablation (n = 79) or previously untested antiarrhythmic drugs (n = 76).

Main outcomes and measures: Primary outcome was the General Health subscale score (Medical Outcomes Study 36-Item Short-Form Health Survey) at baseline and 12 months, assessed unblinded (range, 0 [worst] to 100 [best]). There were 26 secondary outcomes, including atrial fibrillation burden (% of time) from baseline to 12 months, measured by implantable cardiac monitors. The first 3 months were excluded from rhythm analysis.

Results: Among 155 randomized patients (mean age, 56.1 years; 22.6% women), 97% completed the trial. Of 79 patients randomized to receive ablation, 75 underwent ablation, including 2 who crossed over to medication and 14 who underwent repeated ablation procedures. Of 76 patients randomized to receive antiarrhythmic medication, 74 received it, including 8 who crossed over to ablation and 43 for whom the first drug used failed. General Health score increased from 61.8 to 73.9 points in the ablation group vs 62.7 to 65.4 points in the medication group (between-group difference, 8.9 points; 95% CI, 3.1-14.7; P = .003). Of 26 secondary end points, 5 were analyzed; 2 were null and 2 were statistically significant, including decrease in atrial fibrillation burden (from 24.9% to 5.5% in the ablation group vs 23.3% to 11.5% in the medication group; difference -6.8% [95% CI, -12.9% to -0.7%]; P = .03). Of the Health Survey subscales, 5 of 7 improved significantly. Most common adverse events were urosepsis (5.1%) in the ablation group and atrial tachycardia (3.9%) in the medication group.

Conclusions and relevance: Among patients with symptomatic atrial fibrillation despite use of antiarrhythmic medication, the improvement in quality of life at 12 months was greater for those treated with catheter ablation compared with antiarrhythmic medication. Although the study was limited by absence of blinding, catheter ablation may offer an advantage for quality of life.

Trial registration: clinicaltrialsregister.eu Identifier: 2008-001384-11.

Conflict of interest statement

Conflict of Interest Disclosures: Dr Blomström-Lundqvist reports receiving grants from Medtronic during the conduct of the study; and personal fees from Bayer, Sanofi, Boston Scientific, and Merck Sharp & Dohme outside the submitted work. Dr Gizurarson reported a patent pending (WO 2015/149153A1). Dr Bergfeldt reports receiving personal fees from Sanofi, Bristol-Myers Squibb, Bayer, and Pfizer outside the submitted work. Dr Raatikainen reports receiving grants from Biosense Webster outside the submitted work. No other disclosures were reported.

Figures

Figure 1.. Patient Enrollment, Randomization, and Follow-up

Patients were distributed among centers as follows: 49% of patients from Uppsala University hospital, 28% from Sahlgrenska Academy University hospital, 16% from Karolinska University hospital, 7% from Umeå University hospital, and 1% from Tampere University hospital.

Figure 2.. Primary and Secondary End Points: Quality-of-Life Scores by Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36)

Quality-of-life scores by the SF-36 survey in patients allocated to catheter ablation vs antiarrhythmic medication, with the Swedish general population as reference. The left and right edges of the boxes indicate the interquartile range (IQR). The dot inside indicates the mean value. The line inside the box indicates the median value. The whiskers extend from each box to the farthest point that remains within the end of the box ± 1.5 × IQR. Outliers are observations that are more extreme than ± 1.5 × IQR and marked by small circles. A, At baseline the scores in the treatment groups were comparable and lower than in the Swedish normal population. Swedish norms originate from the SF-36 instruction manual. B, At 12-month follow-up, the ablation group improved significantly more than the medication group in all subscales except Bodily Pain and Social Functioning and reached the same score levels as the Swedish normal population. The Role Emotional result in the 12-month plot for the ablation group is explained by the fact that 89% of patients had a score of 100, so that quartiles 1 through 3 were all 100.

Figure 3.. Secondary End Point Atrial Fibrillation Burden From the Implantable Cardiac Monitor

A, The box plot shows atrial fibrillation burden during run-in and at 4 points during follow-up in patients allocated to catheter ablation vs antiarrhythmic medication, with median values (horizontal line inside the box) and interquartile range (IQR, depicted by the bottom and top edges of the box). Whiskers that extend from each box indicate the range of values that are outside of the IQR but not far enough to be considered outliers. Outliers are observations that are more extreme than ± 1.5 × IQR and are marked by circles. The large dot indicates the mean value. B, Atrial fibrillation burden displayed individually in both treatment groups. The parallel line plot is sorted by treatment group and prevalues (percentage of time) and then, within equal prevalues, postvalues. Pre- and postvalues of each patient on a common axis are shown, with difference depicted by the length of the line that runs between them. The boxes and whiskers are defined as in panel A. AF indicates atrial fibrillation; pre, run-in; and post, month 12.

Figure 4.. Secondary End Point Event-Free Survival From Atrial Fibrillation

Kaplan-Meier curves comparing survival free from atrial fibrillation episodes according to implantable cardiac monitor (A) and cumulative 24-hour Holter recordings in the 2 treatment groups (B). There were no significant differences between treatment groups. Events were not counted during the first 90-day blanking period (a period of therapeutic stabilization after ablation during which any occurrence of atrial fibrillation is not considered treatment failure or atrial fibrillation recurrence). For the implantable cardiac monitor, the median (quartile 1-3) observation time was 12.2 months (12.0-12.5 months) for the ablation group and 12.1 months (11.9-12.6 months) for the drug group. The 24-hour Holter recordings were obtained for 12.0 months (12.0-12.0 months) in the ablation group and 12.0 months (12.0-12.0 ) in the antiarrhythmic medication group.