Abstract
This prospective study evaluates the impact of radiofrequency ablation (RFA) on cardiorespiratory indicators in patients with long-standing persistent atrial fibrillation admitted to the Heart Center UMC between January 2022 and April 2024 in Astana, Kazakhstan. The study aims to assess the functional cardiac benefits of RFA. Out of 717 registered atrial fibrillation patients, 104 were examined before and 3 months after ablation, focusing on cardiorespiratory parameters. A before-and-after analysis using linear mixed models was applied to evaluate changes in cardiorespiratory parameters post-RFA. Significant improvements were noted across various measures. VO2 max increased from 11.5 ± 4.4 mL/kg/min to 18.0 ± 4.5 mL/kg/min (p < 0.001). Oxygen uptake improved from 7.2 ± 2.6 mL/beat to 11.0 ± 3.4 mL/beat (p < 0.001). The 6-min walking test distance rose from 306 ± 82 m to 400 ± 48 m (p < 0.001). METs increased from 4.4 ± 1.6 to 8.0 ± 1.3 (p < 0.001). Heart rate at peak exercise decreased from 175.5 ± 18.6 to 147.2 ± 12.3 beats per minute (p < 0.001). NT-proBNP levels decreased from 1357 ± 1182 to 415 ± 339 pg/mL (p < 0.001). Patients with persistent atrial fibrillation undergoing RFA showed functional improvements in CPET indicators such as VO2 max, METs, O2 pulse, heart rate, and the 6-min walking test. Improvements were also seen in Nt-proBNP analysis. These results emphasize the need for longitudinal follow-up to optimize outcomes and minimize medical risks.