Catheter ablation compared to antiarrhythmic drugs in patients with atrial fibrillation : A study focusing on arrhythmic burden and quality of life

Sammanfattning: Patients with atrial fibrillation (AF) experience symptoms and have impaired health-related quality of life (HRQoL). Rhythm control therapy, including antiarrhythmic drugs (AAD) and catheter ablation for pulmonary vein isolation, aims to relieve symptoms and improve HRQoL. This thesis aimed to study HRQoL and rhythm outcomes after rhythm control therapy and to explore the relationship between symptoms, HRQoL, and AF. In the short-term 12-month follow-up study after cryoballoon catheter ablation, patients with persistent and paroxysmal AF had a similar symptom burden and HRQoL at follow-up. However, freedom from AF recurrence was lower in patients with persistent AF (64.9%) than paroxysmal AF (82.2%). In the long-term 48-month follow-up study, patients assigned to AADs and catheter ablation for pulmonary vein isolation improved their HRQoL compared to before treatment, without differences in improvement between the groups. Patients in the ablation group had a higher reduction in AF burden than the AAD group (-91.4% versus -52.7%) and a longer time to first AF recurrence of ≥1 hour (median 257 versus 180 days). The AAD group had a four times higher crossover rate than the AAD group. Atrial fibrillation burden (percentage of time in AF) had the greatest impact on HRQoL, as opposed to the duration and frequency of AF episodes. In addition, if AF was the prevailing rhythm when assessing HRQoL with generic questionnaires, the HRQoL was lower than in those with sinus rhythm. However, the prevailing rhythm did not influence the symptom assessment. In conclusion, regardless of the type of AF, patients presented similar short-term symptoms and HRQoL after cryoballoon ablation, although patients with persistent AF had worse rhythm outcomes. Even though the long-term rhythm outcomes were better in the ablation group, HRQoL improvements did not differ between catheter ablation and AAD. This was probably explained by crossover. The prevailing rhythm should be considered when interpreting results from generic HRQoL questionnaires to ensure more accurate results. Furthermore, the results indicate that the AF burden reflects HRQoL the most, as opposed to the duration and frequency of AF episodes. AF burden may therefore be the preferred rhythm outcome measure in future trials of rhythm control.