The need to improve effectiveness
The overall information that we collect from these experiences notifies us that LPW plays a pivotal role in the maintenance of AF and it should be included in the ablative approach of patients with persistent AF. Probably in order to obtain an effective and durable LPWI the scheme of lesions should be properly revisited as to reduce the likelihood of electrical reconnection of the posterior wall. My own perplexity is about the ablative modality of creating linear lesions reported in this and other studies, since the rate of inconsistency of the lesions connecting the contralateral PVs is well documented. In this regards, the promotion of LPW homogenization by moving a circular catheter around the PV antrum can significantly reduce the arrhythmia recurrence rate as compared to the circle of contiguous lesions (12). Unfortunately, even in the study by Sayuri et al the rate of LPW reconnection is high, underlying the technical difficulty to achieve a durable effectiveness. The good news from the study is revealed by the lower occurrence of atrial tachycardia (AT, 9%) in patients who underwent PVI plus LPWI and this is much lower than in previous studies, where the rate of recurrent AT varied from 5% to 59%. (see 21-23 Sayuri). On the other hand, due to the disparity of approaches employed in the different studies, it is difficult a fair and objective comparison. Due to the observational nature of this single center study and the limited number of patients included, caution needs to be advocated concerning the value of creation linear lesions with the current technology. The emerging ablative techniques, such as high power-short duration ( see 27 Sayuri) and the use of ablation index (see 28 Sayuri) or the promising thermal/non-thermal pulse field ablation technology might constitute the technical key improvement to provide an effective LPWI. Future studies are needed to evaluate whether these additional approaches improve clinical outcomes, provided isolation of LPW is guaranteed
Even with the inherent limitations of the study, we need to applaud Sayuri er al for drawing our attention to the pivotal role of left posterior wall in the initiation and maintenance of AF and, thus reinforcing the concept of walking out of the PVs towards the posterior wall. Achieving proven isolation of LPW is essential to promote additional benefits over PVI alone in the treatment of persistent AF and the adoption of new ablation settings and novel energy delivering is required to improve procedural outcome over the follow-up