Follow-up and effectiveness
Patients were monitored after the first repeat ablation for a median of 2.0 (1.0-3.3) years. During follow-up 142 (52.8%) patients with durably isolated PVs had a recurrence of atrial arrhythmia >90 days post-procedure and 30 (12.7%) patients underwent subsequent repeat ablation within 12-months of the first repeat procedure (Table 2). At last known follow-up moment, 141 (57.3%) patients were still using anti-arrhythmic drugs.
The multivariable Cox proportional hazards model, conducted following multivariable adjustment for age, sex, body-mass index, paroxysmal AF, diabetes, CAD, and hypertension, identified no individual ablation strategy as an independent predictor of AF recurrence (p > 0.05 for all; Figure 4). Subgroup analysis accounting for type of AF (paroxysmal AF or persistent AF), similarly demonstrated no discernible difference in AF recurrence for individual strategies between the two groups [HR 1.001 (95% CI 0.67-1.51)]. Furthermore, no significant associations were observed between the number of ablation strategies adopted and AF recurrence rates, when compared to no additional ablation (p>0.05; Figure 5). Sensitivity analyses confirmed the stability of these findings, reinforcing the conclusion that neither the choice of ablation strategy nor the cumulative number of strategies employed significantly influenced the recurrence of AF post-PVI.
In the multivariate Cox regression model, left atrial size appeared to be the only independent factor associated with an increased risk of atrial arrhythmia recurrence [adjusted HR 1.03 (95% CI 1.01-1.05); Figure 6].