A novel approach for effective superior vena cava isolation using the CARTO electroanatomical mapping system

Abstract

Background Previous studies have demonstrated that some patients have spontaneous right atrium (RA)‐superior vena cava (SVC) conduction block, which could be utilized to isolate the SVC effectively by using the Rhythmia mapping system (Boston Scientific). However, employing this approach for SVC isolation using the CARTO electroanatomical mapping system (Biosense Webster) has not yet been clarified. This study aimed to evaluate the safety and efficacy of SVC isolation using the extended early meets late (EEML) tool with the CARTO system. Methods The patients who underwent SVC isolation using the CARTO system were enrolled in this study. The RA‐SVC conduction block was visualized with an EEML tool. We prospectively assessed the safety and efficacy of SVC isolation using this system. Results We analyzed 54 patients, and all SVCs were successfully isolated with no complications. Altogether, 44 patients (81.5%) had spontaneous RA‐SVC conduction block, and the remaining 10 patients (18.5%) did not. The block group required fewer radiofrequency deliveries for the SVC isolation than the nonblock group (10.7 ± 5.0 vs 15.5 ± 4.8, P = .009). The size of the isolated area in the block group was larger than that in the nonblock group (15.2 ± 5.1 cm2 vs 12.4 ± 2.5 cm2, P = .017). Conclusions Approximately 80% of the patients in this study developed a spontaneous RA‐SVC conduction block, which might contribute to shortening the time of ablation and avoiding complications.

Pseudo superior vena cava entrance block during sinus rhythm uncovered by continuous atrial pacing

“…After completing the PVI, we proceeded with empiric SVC isolation because he had a long SVC sleeve 1,2 . An activation map during sinus rhythm acquired before SVC isolation presented an intrinsic conduction block at the anterolateral side of the right atrium (RA)‐SVC junction, 3,4 whereas the posterior side was conductible (Figure 1A–C). We aimed to isolate the SVC without encircling ablation and started the ablation from the septal side toward the posterolateral side during sinus rhythm, and the SVC entrance block was observed without RF applications at the anterolateral side (Figure 1D).…”