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Percutaneous transcatheter aortic valve implantation for degenerated surgical bioprostheses: the first case series in Asia with one-year follow-up.

INTRODUCTION
Percutaneous transcatheter aortic valve implantation (TAVI) has become an established therapy for inoperable and high-surgical-risk patients with severe aortic stenosis. Although TAVI in patients with degenerated surgical aortic bioprostheses (i.e. valve-in-valve TAVI) is increasingly reported in Western studies, such data is lacking in Asian patients. We describe the initial experience of valve-in-valve TAVI in Asia.


METHODS
Eight patients who underwent valve-in-valve TAVI due to degenerated aortic bioprostheses were enrolled. The mechanism of bioprosthetic valve failure was stenotic, regurgitation or mixed. All procedures were performed via transfemoral arterial access, using the self-expanding CoreValve prosthesis or balloon-expandable SAPIEN XT prosthesis.


RESULTS
The mean age of the patients was 71.6 ± 13.2 years and five were male. Mean duration to surgical bioprosthesis degeneration was 10.2 ± 4.1 years. Valve-in-valve TAVI was successfully performed in all patients. CoreValve and SAPIEN XT prostheses were used in six and two patients, respectively. There were no deaths, strokes or permanent pacemaker requirement at 30 days, with one noncardiac mortality at one year. All patients experienced New York Heart Association functional class improvement. Post-procedure mean pressure gradients were 20 ± 11 mmHg and 22 ± 8 mmHg at 30 days and one year, respectively. Residual aortic regurgitation (AR) of more than mild severity occurred in one patient at 30 days. At one year, only one patient had mild residual AR.


CONCLUSION
In our experience of valve-in-valve TAVI, procedural success was achieved in all patients without adverse events at 30 days. Good clinical and haemodynamic outcomes were sustained at one year.