Incidence and Characteristics of Superior Vena Cava Impact After Pulsed-Field Ablation of the Right Pulmonary Veins.

Background: Superior vena cava (SVC) conduction delay or isolation during right superior pulmonary vein (RSPV) ablation using thermal ablation technologies has been previously described because of the anatomical proximity of the SVC to the RSPV. We aimed to evaluate the impact of pulsed-field ablation (PFA) on the SVC.

Methods: Sixty-eight consecutive patients who underwent pulmonary vein isolation (PVI) with PFA were enrolled: 17, Varipulse; 26, PulseSelect; 25, FARAPULSE. Right atrium mapping was performed before and after PVI to evaluate the impact of PFA on the SVC.

Results: A low-voltage area (< 0.5 mV) of ≥ 0.5 cm2 newly appeared in the SVC after PFA in 56 (82.4%) patients, including whole circumferential SVC impact in 10 (14.7%) patients. The incidence of SVC impact was significantly lower in patients treated with Varipulse catheters than in those treated with other PFA systems (Varipulse 52.9% vs. PulseSelect 96.2% vs. FARAPULSE 88.0%, p = 0.0009). The distance between the RSPV and SVC moderately correlated with SVC impact irrespective of the catheter used. Patients with SVC deformity, defined as a curve-shaped SVC with two narrow pointed ends resembling the moon (less than half of a circle), showed a significantly higher incidence of whole circumferential SVC impact than did those without (38.5% vs. 9.1%, p = 0.018).

Conclusions: RSPV isolation with PFA can induce SVC impact regardless of the different PFA systems. SVC deformity and anatomical distance between the RSPV and SVC significantly correlated with SVC impact occurrence. Further studies are needed to confirm the clinical significance of this impact.