A comparison of laser, electrosurgical, and mechanical transcatheter traversal of calcified aortic valve leaflets.

Objective: Leaflet laceration can be an important adjunct to transcatheter aortic valve replacement to avoid coronary occlusion and to facilitate future percutaneous coronary access. The most technically challenging step is the initial leaflet traversal needed to start laceration. If traversal is achieved, then laceration is usually possible. Successful traversal depends on the operator's ability to locate a noncalcified location on the cusp. To inform the design of improved laceration devices, we performed an in vitro comparison of laser, electrosurgical, and mechanical traversal in human aortic leaflets obtained during surgical aortic valve replacement. Methods: Laser, electrosurgical, and mechanical traversal were attempted in noncalcified and calcified regions of 5 human leaflets. Laser power and frequency settings were selected based on initial experiments using phantom models of calcified leaflets. In laser/electrosurgical traversal, an optical fiber/guidewire was preloaded against the leaflet, energy was applied, and traversal time was recorded. In mechanical (needle) traversal, contact force was incrementally increased to a maximum of 20 N. Results: In noncalcified regions, traversal time using all 3 methods was less than 1 second (n = 5). Mechanical traversal required a contact force of 0.7 ± 0.3 N. In calcified regions (n = 5), laser traversal was always successful (0.8 ± 0.7 seconds), electrosurgery always failed, and mechanical traversal (80% successful) required forces up to 10 N. Conclusions: These results suggest that laser-based traversal may be an effective technique for patients with highly calcified leaflets, whereas electrosurgery and mechanical cutting may be best suited for leaflets in which noncalcified regions can be targeted.