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Published on: December 11, 2017
Balloon-Assisted Leaflet Laceration Using Modified UNICORN Technique in Native Valve TAVR
Charishma S Nallapati1, Andres Hughes1, Nadeen Faza1
1Houston Methodist DeBakey Heart & Vascular Center, Houston, Texas, USA.
Objective:
Coronary obstruction due to displacement of calcified native valve leaflets over the coronary ostia is a life-threatening complication of transcatheter aortic valve replacement (TAVR). Undermining iatrogenic coronary obstruction with radiofrequency needle (UNICORN) has emerged as an innovative electrosurgical method for preventing coronary obstruction, primarily in valve-in-valve TAVR. A native-valve modification is described.
Key Steps:
First, the target leaflet is traversed using transcatheter electrosurgery with angiographic and echocardiographic guidance. Then a series of balloon valvotomies are performed followed by leaflet laceration with a large noncompliant balloon before implantation of the balloon-expandable transcatheter heart valve.
Potential Pitfalls:
Malalignment in traversing the target aortic leaflet can lead to ineffective splay or damage to nearby structures.
Take-Home Message:
The modified UNICORN TAVR technique is an alternative to bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction when bulky leaflet calcification is present at the leaflet tip, while also preserving superior coronary access compared with the snorkel technique.
