Abstract Body (Do not enter title and authors here): Introduction: Redo-transcatheter aortic valve replacement (TAVR) is a promising treatment for transcatheter aortic valve degeneration, becoming increasingly relevant with an aging population. In redo-TAVR, the leaflets of the initial (index) transcatheter aortic valve (TAV) are displaced vertically when the second TAV is implanted, creating a cylindrical cage that can impair coronary cannulation and flow. The risk of coronary obstruction after redo-TAVR can reach as high as 20% and is affected by several factors, including the first TAV design, implantation depth, commissural alignment, and choice of the second TAV. Preventing coronary obstruction and maintaining coronary access is essential, especially in young and low-risk patients.

Hypothesis: Laser ablation of TAV index leaflets can effectively create openings to prevent coronary obstruction and ensure coronary access in at-risk patients undergoing redo-TAVR.

Aim: This study aimed to develop a new leaflet modification strategy using laser ablation to prevent coronary obstruction and facilitate coronary access after redo-TAVR.

Methods: To evaluate the feasibility of the leaflet modification technique using laser ablation, initially, a medical-grade ultraviolet laser was used for ablation through pericardial leaflet tissue. Following this intervention, computational fluid dynamics simulations were utilized to assess the efficacy of the resulting perforations in promoting coronary flow after sinus sequestration in redo-TAVR. These simulations played a crucial role in ensuring that these changes would facilitate the restoration of coronary circulation.

Results: Laser ablation of pericardium leaflets was successful, demonstrating the feasibility of creating openings in the TAV leaflets (Fig. 1a). Flow simulation results showed that ablation of index valve leaflets can effectively mitigate the flow obstruction caused by sinus sequestration in redo-TAVR, with the extent of restoration dependent on the number and location of the ablated openings (Fig. 1b).

Conclusions: Laser ablation could be a viable method for leaflet modification in redo-TAVR, serving as a new tool in interventional procedures.