Impact of premature ventricular contraction on the clinical outcomes after atrial fibrillation ablation

Background Although a high burden of premature ventricular contractions (PVCs) is reported to be associated with new-onset atrial fibrillation (AF), the importance of a high PVC burden after AF ablation is still unknown. Purpose The study aimed to evaluate the impact of high-burden PVC on the clinical outcomes after AF ablation. Methods We retrospectively investigated consecutive 1226 patients who underwent AF ablation between January 2016 and December 2019. After excluding 530 patients without a 24-hour Holter electrocardiogram (ECG), the current study population consisted of 696 patient with a 24-hour Holter ECGs after AF ablation. Of these, 139 patients had high-burden PVC (≥ 1%) and 557 patients had low-burden PVC (< 1%). The outcome measures were compared between the two groups. In the high-burden PVC group, PVCs were recorded on twelve-lead ECGs in 127 patients. The PVCs were classified by their origin based on the twelve-lead ECG. Results Patients with high-burden PVC were older and had more persistent AF and larger left atrial diameter. There was no significant difference in the three-year AF/atrial tachycardia (AT)-free survival rates between the high- and low-burden PVC groups (high-burden PVC 79.0%, low-burden PVC 71.4%, P=0.15). In contrast, the three-year incidence of hospitalization for heart failure was significantly higher in the high-burden PVC group than in the low-burden PVC group (6.1% vs. 2.5%, P=0.002). The estimated origin of PVC was most frequent in the order of left ventricular outflow tract (LVOT) (37.0%), right ventricular non-outflow tract (RVNOT) (22.8%), right ventricular outflow tract (RVOT) (21.3%) and left ventricular non-outflow tract (LVNOT) (18.9%). There was no significant difference in the AF/AT free survival rate among the origins of PVC (RVOT 65.5%, LVOT 82.0%, RVNOT 82.5%, LVNOT 79.0%, P=0.53). At a second procedure, the reconnection rate of pulmonary vein isolation tended to be higher in the high-burden PVC group (8 of 20 patients: 40%) compared with the low-burden PVC group (33 of 99 patients: 33%). Conclusions The presence of high-burden PVC after AF ablation was not associated with AF/AT recurrence, but was associated with hospitalization for heart failure. Also AF/AT recurrence did not depend on the estimated origin of PVC. High-burden PVC may cause degeneration primarily in the pulmonary vein.