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Updated: Feb 10, 2026

Standardized Technique of Aortic Valve Re-implantation for Valve-sparing Aortic Root Replacement
Published on: December 11, 2017
Efficacy and Safety of Electrosurgical Balloon-Assisted Leaflet Modification to Prevent Coronary Obstruction During
Mostafa Naguib1, Chantal Y Asselin1, Robert Kipperman1
1Gagnon Cardiovascular Institute, Atlantic Health System, Morristown, New Jersey, USA.
Background:
Coronary obstruction (CO) during transcatheter aortic valve replacement (TAVR) is associated with significant morbidity and mortality. UNICORN (Undermining Iatrogenic Coronary Obstruction with Radiofrequency Needle) is a novel technique designed to prevent CO by performing electrosurgical leaflet traversal followed by intraleaflet valve implantation or complete leaflet laceration accomplished using noncompliant balloons. However, its efficacy and safety are not well established.
Methods:
We retrospectively reviewed all patients who underwent UNICORN-assisted TAVR for both valve-in-valve and native valve procedures at a single high-volume center between September 2024 and September 2025. Patients were selected based on preprocedural cardiac computed tomography demonstrating high anatomic risk for CO. In all cases, the target leaflet was traversed using an electrified 0.014″ wire, followed by serial noncompliant balloon dilatations of the leaflet to either achieve complete leaflet laceration or to accommodate for intra-leaflet valve implantation. Balloon-expandable valves were used in all procedures.
Results:
Fifteen patients underwent UNICORN-assisted TAVR. Twelve were valve-in-valve cases, and 3 involved native valves. The right coronary cusp was targeted in 11 procedures and the left in 6, including 2 requiring bileaflet modification. Technical success was achieved in all cases (100%). Procedural success was achieved in 93.3%. One patient developed acute CO due to skirt-related occlusion after a high implant in a degenerated self-expanding valve, requiring single-vessel coronary artery bypass surgery. No bailout coronary stenting was required. There were no in-hospital deaths or disabling strokes. All patients were alive at 30-day follow-up.
Conclusions:
In this single-center experience, UNICORN appears technically reproducible, effective in preventing CO, and safe in TAVR patients at high-risk for CO.
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