Redo Ablation Following LSI Algorithm-Guided High-Power Short-Duration vs LSI Algorithm-Guided Conventional...

Clinical studies have compared conventional radiofrequency with high-power, short-duration (HPSD) delivery for pulmonary vein (PV) isolation. However, few have used indices to guide applications or reported on redo procedures.

The goal of this study was to analyze redo procedures in patients who underwent their first PV isolation using Lesion Size Index (LSI) algorithm-guided radiofrequency with HPSD or conventional radiofrequency.

We retrospectively analyzed redo procedures in 701 consecutive patients who underwent a first PV isolation with LSI algorithm-guided radiofrequency. The first 362 patients were treated with 30 W, and the subsequent 339 received HPSD ablation (50 W). Gap sites and epicardial connections were identified by using the pace-and-map maneuver.

A total of 93 patients (71 and 22 in the conventional and HPSD groups, respectively) underwent a redo procedure. Eighteen patients (5%) in the conventional group and 5 (1.5%) in the HPSD group underwent the redo procedure during the first year postablation (P = 0.009) and 18 (5%) and 6 (1.8%) in the second year (P = 0.020). Per-vein analyses suggest that in the HPSD group, the proportion of isolated PVs was higher (32% vs 18%; P = 0.048), the reconnection of the right inferior PV lower (25% vs 62%; P = 0.021), and gaps in the ridge and Marshall epicardial connections more frequent (50% vs 22%; P = 0.012).

LSI algorithm-guided PV isolation using HPSD ablation at 50 W is associated with lower rates of redo procedures and PV reconnection compared with 30 W ablation at the same LSI algorithm target, suggesting greater durability. The higher reconnection rate observed in the ridge/Marshall region likely reflects insufficient lesion depth of HPSD RF in thicker atrial tissue.