Influence of the initial expansion position of balloon-expandable valves on valve distortion in transcatheter aortic valve implantation

Abstract Background: Transcatheter heart valve (THV) distortion is a commonly observed phenomenon during transcatheter aortic valve implantation (TAVI). However, the influence of the initial expansion position of the THV on its distortion remains unclear. Purpose: The purpose of the present study was to compare the degree of THV distortion based on the initial expansion position and to evaluate its impact on clinical outcomes after TAVI. Methods: In a single-center study, patients who underwent TAVI with a balloon-expandable valve were enrolled in the present study. All THVs used in the present study were SAPEN 3. Patients were divided into NCC (non-coronary cusp) group and the non-NCC group based on the initial position of valve expansion. (Figure1A-B) The relationship between the initial valve position and the L/N ratio; stent length on the LCC (left-coronary cusp) side / NCC side ratio, which reflects the degree of THV distortion was analyzed. (Figure1C) In addition, the prognostic impact of initial valve position and THV distortion was also assessed. Results: Of a total of 116 patients, 72 patients were classified as NCC group and 44 as non-NCC group at the initial expansion position. The NCC group had a significantly lower L/N ratio than the non-NCC group, indicating greater distortion in the NCC group. (0.93 ± 0.06 vs. 0.99 ± 0.07, p 0.01, Figure1D) There were no significant differences in 2-year all-cause mortality or heart failure rehospitalization between the groups.(Figure2A) Additionally, post-operative transthoracic echocardiography parameters showed no significant differences between the groups.(Figure2B a-b) Conclusion: The initial expansion position was associated to the THV distortion, which did not affect the clinical course during the 2 years after TAVI.