Catheter stability and ablation characteristics
Baseline patient characteristics are provided in Table 1. Ventricular-paced patients had significantly larger left atrial diameters (4.9 ± 0.6cm vs 4.4 ± 0.8cm, p = 0.02), but similar left atrial volume indices (41 ± 15mL/m2 vs 33 ± 8mL/m2, p = 0.14), as well as greater time since initial diagnosis of AF (4.4 ± 4.7yrs vs 2.5 ± 4.2yrs, p = 0.02), compared to atrial-paced patients. Otherwise, there were no significant clinical or echocardiographic differences between the two groups. With respect to ablation characteristics (Table 2), there were no significant differences in measures of catheter stability between the atrial-paced and ventricular-paced patients. Atrial-paced patients had similar mean catheter excursions (0.79 ± 0.15mm vs 0.77 ± 0.10mm, p = 0.62), maximal catheter excursions (2.14 ± 0.45mm vs 2.15 ± 0.35mm, p = 0.94), and contact force variability (4.2 ± 1.0g vs 4.1 ± 0.9g, p = 0.58), compared to ventricular-paced patients (Figure 2). In addition, the two groups had similar mean absolute impedance declines (7.7 ± 1.5ohms vs 7.1 ± 1.7ohms, p = 0.15) and percentage impedance declines (6.3 ± 1.2% vs 5.8 ± 1.2%, p = 0.12). Ventricular-paced patients had greater average contact forces than atrial-paced patients (14.5 ± 2.4g vs 13.0 ± 1.7g, p = 0.02) as well as greater force-time-integrals (FTIs, 107 ± 20gs vs 95 ± 15gs, = 0.02), which was driven by the greater contact forces.