IVUS-Guided UNICORN Leaflet Modification During Redo TAVR to Prevent Coronary Obstruction

Abstract

Background Coronary obstruction is a rare but potentially fatal complication of transcatheter aortic valve replacement (TAVR), particularly during valve-in-valve and TAVR-in-TAVR procedures. Leaflet modification techniques have emerged to reduce this risk. Case Summary A 67-year-old woman with severe degeneration of a 26-mm SAPIEN 3 transcatheter heart valve presented with acute heart failure. Computed tomography demonstrated severe prosthetic stenosis and a high risk of left coronary obstruction (virtual valve-to-coronary distance 3.4 mm). Redo TAVR was performed using intravascular ultrasound (IVUS)-guided UNICORN (Undermining Iatrogenic Coronary Obstruction with Radiofrequency Needle) leaflet modification, followed by implantation of a 23-mm RESILIA valve. IVUS enabled precise leaflet traversal and real-time assessment of the relationship between the modified leaflet, valve frame, and left main coronary artery, resulting in an excellent procedural and hemodynamic outcome. Conclusions This is the first reported IVUS-guided UNICORN leaflet modification during TAVR-in-TAVR, highlighting its potential to improve procedural precision and safety in patients at high risk of coronary obstruction.