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UNICORN During Transcatheter Aortic Valve Replacement in Native and Bioprosthetic Aortic Valves: A Multicenter Study
Elsa Hebbo1, John T D'Angelo1, Anton Camaj2
1Emory University Hospital Midtown, Atlanta, Georgia, USA.
Background:
UNICORN (undermining coronary obstruction with radiofrequency "needle") has been adopted by some operators to prevent coronary obstruction during transcatheter aortic valve replacement (TAVR). More clinical data are needed to evaluate UNICORN outcomes.
Objectives:
The aim of this study is to describe preliminary outcomes of UNICORN during TAVR.
Methods:
Nine sites contributed consecutive patients undergoing UNICORN TAVR from March 2024 to May 2025. Primary success was UNICORN TAVR without composite periprocedural coronary obstruction, reintervention, or death. Primary safety endpoints were intraprocedural hypotension plus overall 30-day safety, which included 30-day death, stroke, coronary obstruction requiring reintervention, stage 3 or 4 acute kidney injury, life-threatening bleeding, major vascular complication, and valve-related reintervention. Two UNICORN techniques, intraleaflet deployment and full-leaflet tearing, were used.
Results:
Fifty-three patients (8 native aortic valves, 30 surgical valves, and 15 transcatheter valves) were included. Left-sided and right-sided UNICORN procedures were performed in 30 (57%) and 19 (36%), respectively. UNICORN was bilateral in 4 (8%). Eleven (21%) underwent contralateral BASILICA (bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction), and 3 (6%) received contralateral snorkel-stent protection. Forty patients (76%) underwent intraleaflet deployment, and 13 (24%) underwent full-leaflet tearing. Primary success occurred in 51 patients (96%). Two (4%) experienced coronary obstruction and required rescue percutaneous coronary intervention. Overall 30-day safety was observed in 46 patients (87%), with strokes in 3 (6%), life-threatening bleeding in 2 (4%), and major vascular complications in 2 (4%). Intraprocedural hypotension occurred in 12 (23%). There were no deaths, valve-related reinterventions, or stage 3 to 4 acute kidney injury at 30 days.
Conclusions:
UNICORN during TAVR was successful in preventing coronary obstruction. Intraprocedural hypotension requiring vasopressor support was frequent. UNICORN should be considered in cases in which lower risk options are unlikely to be successful.