Influence of power setting on superior vena cava potential during right pulmonary vein isolation

High-power short-duration (HP-SD) ablation could reduce collateral tissue damage by shortening the conductive heating phase. However, it is difficult to evaluate the transmural effect of ablation lesions during pulmonary vein isolation (PVI) procedures. The present study aimed to evaluate the change in superior vena cava (SVC) potential delay as a surrogate marker of collateral tissue damage during right PVI, which is adjacent to SVC.

Out of 250 consecutive patients who underwent PVI, 86 patients in whom SVC potential during sinus rhythm was recorded both before and after right PVI were analyzed. In 46 of the patients, an HP-SD setting of 45-50 W was used (HP-SD group). In the remaining 40 patients, a conventional power setting of 20-30 W was used (conventional group). We compared the change in SVC potential delay after right PVI, radiofrequency energy, and mean contact force in the anterior-superior right PVI line, which was close to the posterior aspect of SVC, between the two groups.

Although the total delivered radiofrequency energy (2,924 J vs. 2,604 J) and the mean contact force (18.5 g vs. 16.0 g) in the SVC overlapping area did not differ, the change in SVC potential delay after right PVI was significantly longer in the conventional group compared to the HP-SD group (5.0 ms vs. 0.0 ms, p < 0.001).

The changes in SVC potential delay after right PVI might be a surrogate marker of collateral tissue damage according to the used energy settings.