The absence of real-time pulmonary vein isolation during cryoballoon ablation is associated with atrial fibrillation recurrence and pulmonary vein reconnection : Insights from the Middelheim-PVI Registry 2.

BACKGROUND: Absence of real-time pulmonary vein (PV) isolation (PVI) occurring in 15-40% of PVs during cryoballoon ablation (CBA) of atrial fibrillation (AF) raises doubt about adequate PVI. Aim of the present study is to determine whether real-time PVI during CBA is predictive of long-term clinical outcome and durability of PVI. METHODS: Eight hundred three AF patients (64 ± 10 years, 68% males) undergoing CBA were studied. The cohort was divided in 4 groups according to the number of PVs without real-time PVI: none (N = 252 [31.4%]), 1 (N = 255 [31.8%]), 2 (N = 159 [19.8%]), and 3-4 (N = 137 [17.1]). RESULTS: At 3 years, 279 (34.7%) patients had recurrence of AF of which 188 underwent repeat ablation. A vein without real-time PVI was associated with AF recurrence (HR = 1.275; 95% CI 1.134-1.433; p < 0.01), independent of persistent AF type (HR = 2.075; 95% CI 1.584-2.738; p < 0.01), left atrial diameter (HR = 1.050; 95% CI 1.028-1.072; p < 0.01), and diagnosis-to-ablation time (HR = 1.002; 95% CI 1.000-1.005; p = 0.04). Highest success was achieved with present real-time PVI in all veins (77.4%), gradually decreasing per increasing number of absent real-time PVI: 66.3% for 1 vein, 58.5% for 2, and 48.9% for 3-4 veins (p < 0.001). At repeat ablation (N = 188), PV reconnection was seen in 99/430 (23.0%) versus 83/288 (28.8%) veins with and without real-time PVI, respectively (p = 0.08). Right inferior PVs (RIPVs) with real-time PVI were less reconnected than RIPVs without real-time PVI: 29.7% versus 43.7% (p = 0.047). CONCLUSION: The absence of real-time PVI during CBA independently predicts AF recurrence with a 30% gradual decrease in outcome per increase in veins without real-time PVI. Real-time PVI is particularly important for the RIPV to achieve durable PVI.

Electroanatomical mapping improves procedural outcomes of cryoballoon pulmonary vein isolation (the Achieve Plus study).

BACKGROUND: Validation of pulmonary vein (PV) isolation (PVI) using only the Achieve catheter following cryoballoon ablation (CBA) is imperfect since pulmonary vein potentials (PVP) can be recorded in only 50-85% of the veins and residual PVP are found in up to 4.3-7.6% of the isolated veins in remapping studies. OBJECTIVE: To study if addition of electroanatomical mapping to Achieve catheter-guided CBA is superior for PVI. METHODS: One hundred patients were randomized between Achieve catheter-guided CBA (control group; N = 50) and Achieve catheter-guided CBA with additional EnSite voltage maps performed pre- and post-CBA (Achieve Plus group; N = 50). Confirmation of PVI was done by circular mapping catheter (CMC) and EnSite mapping by a second blinded operator. RESULTS: Despite apparent PVI in all PVs after CBA, incomplete PVI was present in 0 out of 50 patients (0%) and 0 out of 204 PVs in the Achieve Plus group versus 6 patients out of 50 (12%; P = 0.012) and 6 out of 203 PVs (3%; P = 0.013) in the control group. All 6 non-isolated PVs could be successfully isolated by additional cryoapplications. Procedure time was longer in the Achieve Plus group (75.76 ± 21.65 vs 66.06 ± 16.83 min; P = 0.014) with equal fluoroscopy times (14.85 ± 6.41 vs 14.33 ± 8.55; P = 0.732). CONCLUSION: The addition of electroanatomical EnSite mapping to the Achieve catheter improves the PVI rate of CBA and could be considered for future use. Design and Results of the Achieve Plus study. The Achieve Plus study shows that the addition of electro-anatomical EnSite mapping to the Achieve catheter improves PVI rate of CBA and could be considered for future use. See text for further explanation. ABBREVIATIONS: CBA: cryoballoon ablation; PVI: pulmonary vein isolation.