TAVI in Patients with Large Aortic Annulus: First Clinical Experience with a New Self-Expandable Prosthesis

Objectives: In the past, optimal positioning and implantation of the Medtronic CoreValve 31mm valve (CV31) has occasionally been technically challenging. The next generation Evolut R 34 mm (Evolut34) was designed for a facilitated implantation in patients with an aortic annulus size between 26 and 30mm with features for resheathing, repositioning and recapturing. The aim of this study was to compare procedural handling and ease of implantation with the Evolut34 and the CV31, respectively.

Methods: Between 06/2011 and 01/2017, seventy-eight patients received the CV31 prosthesis. Since January 2017, fourteen patients were treated with the Evolut34. Preoperative, periprocedural and postoperative data were prospectively collected in a dedicated database and analyzed retrospectively.

Results: No significant differences were seen in the frequency of valve dislocation (Evolut 34 7.1% vs. CV31 7.7%, p = 1.0), the need for a second valve implantation (Evolut34 7.1% vs. CV31 7.7%, p = 1.0), and for postdilatation (Evolut34 50% vs. CV31 46.2%. p = 0.1). Twelve patients (15.4%) receiving the CV31 exhibited more than moderate degree of postprocedural AR. No patient receiving the Evolut34 showed postprocedural AR (p = 0.2). Postoperative need for a pacemaker was 21.4% for the Evolut34 vs. 41% for the CV31, p = 0.2). Procedural time, dose area product, contrast media, and fluoroscopy time were significantly reduced during implantation of the Evolut34 compared with the CV31 (78.2 ± 57.5 minutes vs. 85 ± 28.9 minutes, p = 0.05, 6,184.2 ± 3,140.6 mGy/cm² vs. 14,982.8 ± 8,951.4 mGy/cm², p = 0.006, 119.6 ± 24.1 mL vs. 158.9 ± 54 mL, p = 0.05, 18.5 ± 12.5 minutes vs. 24.8 ± 34 minutes, p = 0.22, respectively).

Conclusion: A large aortic annulus is still a challenge for transcatheter aortic valve implantation. A faster implantation with a reduced application of contrast media and reduced radiation reflects improved and simpler positioning of Evolut34 within a large annulus.