Conformational changes during in vitro balloon fracture of internal aortic annuloplasty ring

ObjectiveHAART 300 (BioStable Science and Engineering, Inc) aortic annuloplasty rings restore physiologic annular geometry during valve repair. Transcatheter valve-in-ring implantation is appealing for recurrent dysfunction but may necessitate balloon fracture of downsized rings. We characterized the feasibility ring changes in preceding fracture.MethodsThe 19-mm, 21-mm, 23-mm HAART were obtained, 23-mm, 24-mm, 25-mm, 26-mm valvuloplasty balloons obtained. Under continuous fluoroscopy video recording, a was inflated within 19-mm at 1 atm/s until or failure occurred. If occurred, experiments sequentially repeated with 1-mm upsized occurred no larger-sized available.ResultsUpon inflation, all exhibited an irreversible conformational change from elliptical, to circular shape posts flaring outward. A burst 21 atm without fracturing ring. The 24-mm fractured 15 atm. Likewise, ruptured 18 21-mm 25-mm Finally, 20 ring, it did elicit confirmational described. All fractures along upslope post. exposed metal frame visible after fracture.ConclusionsFracture possible oversized, high-pressure balloon. However, geometrical subsequent rupture its fabric covering be obstacles safe, vivo fracture.