Atrial Fibrillation Catheter Ablation Increases the Left Atrial Pressure

Background: We previously reported that a high left atrial (LA) pressure is associated with LA stiffness and poor rhythm outcomes after de novo catheter ablation of atrial fibrillation. Herein, we investigated whether radiofrequency catheter ablation generally changes the LA pressure among patients undergoing repeat procedures. Methods: Among 1848 patients who underwent atrial fibrillation catheter ablation, we measured the LA pressure during sinus rhythm in 1687 patients before the de novo ablation (59±11 years, 72.4% men, 72.8% paroxysmal atrial fibrillation) and in 142 with second procedures. We measured the LA pressure immediately after the transseptal puncture at the beginning of the procedure. Results: In the same 142 patients, the degree of LA stiffness, reflected by the LA pulse pressure (LA pp ), was significantly higher in the second procedure than in the de novo procedure ( P <0.001). The degree of the LA pp increase (ΔLA pp ) was significantly higher in patients who underwent additional extrapulmonary vein LA ablation than in those who underwent circumferential pulmonary vein isolation alone ( P =0.010). Extrapulmonary vein LA ablation was independently associated with the ΔLA pp (β=5.70 0.12–11.27; P =0.045). An increased LA pp during repeat procedures was independently associated with a reduced diastolic function (β=2.01 0.08–3.93; P =0.041) without a worsening symptoms (EuroQol-five dimensions) score, 22.2±17.9 months after the de novo ablation. Conclusions: Atrial fibrillation catheter ablation, especially extrapulmonary vein LA ablation, increased the LA stiffness and was associated with a worsening postablation diastolic function. However, the symptom score did not significantly change. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02138695.