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Standardized Technique of Aortic Valve Re-implantation for Valve-sparing Aortic Root Replacement
Published on: December 11, 2017
Leaflet Modification Technique With UNICORN in Failed Aortic Bioprosthesis: Procedural Step-by-Step, Best Practice,
Kwong-Yue Eric Chan1, Ka-Chun Un2, Ho-On Alston Conrad Chiu2
1Cardiology Division, Department of Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China; Cardiology Division, Department of Medicine, Queen Mary Hospital, Hong Kong SAR, China; Cardiac Medical Unit, Grantham Hospital, Hong Kong SAR, China.
None:
The UNICORN (undermining iatrogenic coronary obstruction with radiofrequency needle) technique was developed in 2022 to reduce the risk for coronary obstruction during valve-in-valve transcatheter aortic valve replacement. The procedure involves traversing the target leaflet with an electrified wire, followed by serial dilation with coronary and peripheral balloons. A balloon-expandable valve is then delivered into the de novo fenestration for intraleaflet deployment. As the balloon-expandable valve expands, the target leaflet is opened and displaced away from the at-risk coronary ostium, resulting in a minimal neoskirt on the target side. Since its introduction, the technique has been adopted at numerous centers worldwide, with various modifications and adaptations. In this paper, a step-by-step description of the UNICORN procedure is provided, and troubleshooting strategies for potential challenges are discussed.
