Abstract 2611: Transcatheter Valve Insertion A Model Of Enlarged Right Ventricular Outflow Tracts
Background: Transcatheter pulmonary valve insertion has recently emerged as an alternative to surgery. To extend the indications to patients with large right ventricular outflow tract (RVOT), we previously developed an intravascular device that reduces the diameter of the main pulmonary artery (MPA) allowing the insertion of available valved stents. We report its use in a model of animals with enlarged RVOT and pulmonary valve incompetence (PVI).
Methods and Results: 33 sheep were included. They first underwent surgical MPA enlargement. We then intended to implant percutaneously a reducer followed by the insertion of a valve. Three animals died during interstage. The remaining were sacrificed acutely (group 1, n=6), after a mean follow-up of 1 (group 2, n=12) and 2 months (group 3, n=12). Animals from chronic groups were equally divided into 2 subgroups according to the difference between diameters of the device inserted and MPA (A: < 5-mm, B: ≥ 5-mm). Reducers were inserted successfully (n=30). One embolized after its insertion (Group 3A). A valved stent could be implanted in all animals but one which experienced a balloon ruptured during its inflation leading to incomplete expansion and death of the animal. Six animals had pulmonary regurgitation after valve insertion. Five of them (Group A, n=5; Group B, n=1) had downsizing of the reducer.
Conclusion: Pulmonary valve insertion is possible through a transcatheter technique using a PA reducer. Oversizing of this device reduces the risk of embolisation and paraprosthetic leak.