Background and purpose: Catheter-ablation (CA) of paroxysmal atrial fibrillation (AF) is associated with improvement in symptoms and quality of life (QoL), whilst the effects on functional capacity are underreported. We studied the change in cardiopulmonary exercise testing (CPET) indices of functional capacity from baseline to follow-up in patients undergoing their first CA for paroxysmal AF.
Methods: Consecutive patients who underwent their first CA for paroxysmal AF in our center during 2015, with a >12-month post-procedural follow-up were included. All patients completed the CPET and SF-36 (Short Form Health Survey) questionnaire to evaluate maximal functional capacity and QoL, respectively, at baseline (prior to CA) and 1 year post-CA. The follow-up 24h-Holter-monitoring was performed at 1, 3, 6 and 12 months after CA; finding of any atrial tachyarrhythmia lasting >30 sec was considered the arrhythmia recurrence.
Results: Study group consisted of 50 patients (the mean age 57±12 years, males 76%). The mean left ventricular ejection fraction and left atrial diameter were 61±8% and 41±6 mm, respectively. All patients were free of heart failure; the commonest comorbidities were hypertension (65%) and diabetes mellitus (21%). The follow-up CPET 1 year post CA demonstrated an improvement in maximal functional capacity compared to baseline values, with significant increase in maximal load (123±38 vs. 134±33 W, p=0.012), peak oxygen consumption (VO2max, 18±5 vs. 20±4 mL kg–1 min–1, p=0.001) and peak breathing equivalent (EQ-O2, 28±4 vs. 29±4, p=0.020). The AF-free patients (n=40) had a greater 1-year improvement in work time (22±129 vs. −71±123 sec, p=0.008) and maximal load (15±24 vs. −6±26 W, p=0.005) compared with those expiriencing AF recurrence post-CA (n=10). There was a significant correlation between the 1-year change in SF-36 score and the increase in maximal load (ρ=0.26, p=0.018) and between the 1-year change in SF-36 score and the prolongation of work time (ρ=0.27, p=0.017).
Conclusion: Our study suggests that CA of paroxysmal AF favourably affects the maximal functional capacity, especially in patients with stable sinus rhythm following the procedure. The increase in functional capacity is followed by QoL improvement. This should be considered in treatment decision-making.