Predictors of High Post-Procedural Gradients after Catheter-Based Aortic Valve Implantation Using Direct Flow Medical Bioprostheses.

BACKGROUND: The Direct Flow Medical (DFM) valve is a new non-metallic and repositionable bioprosthesis used for transcatheter aortic valve implantation (TAVI). The study aim was to investigate procedural and post-implant valve data in patients receiving differently sized DFM bioprostheses.

METHODS: Procedural, echocardiographic and computed tomography findings of 28 patients receiving either a 25, 27 or 29 mm DFM bioprosthesis were analyzed.

RESULTS: Implantation of a 29 mm bioprosthesis was associated with longer procedure (p <0.05) and radiation (p <0.05) times, and a higher dose-area product (p <0.01) compared to the 25 mm valve. A high mean post-interventional aortic gradient indicating a suboptimal result was found in 44% patients receiving a 29 mm bioprosthesis, whereas none of the patients with a 25 or 27 mm valve had a high gradient (p <0.05). Aortic valve calcification was greatest in the 29 mm group and correlated with a higher dose-area product (p <0.01).

CONCLUSIONS: DFM bioprosthesis size significantly influences the TAVI procedure and post-implant valve function. Valve calcification and use of the 29 mm DFM bioprosthesis per se possibly predict a more complicated procedure. Therefore, annulus size and valve calcification severity should be taken into consideration when deciding which bioprosthesis type might be best suited for individual patients.