Author + information
- Jérôme Caudron, MD, MSc∗ ()
- ↵∗University Hospital of Rouen, 1 rue de Germont, 76031 Rouen, Cedex, France
I read with great interest the recently published paper by Binder et al. (1) that described the impact of post-implantation SAPIEN XT (Edwards Lifesciences Inc., Irvine, California) geometry and positioning on clinical outcome after transcatheter aortic valve replacement (TAVR). The main finding of the authors is that low implantation depth is associated with clinically significant new conduction disturbances and permanent pacemaker implantation. Although this result was previously reported by our team (2), the authors should be congratulated because the statistical power of their study is much better than ours (89 vs. 34 patients). However, the methodology for measuring the primary endpoint (i.e., the implantation depth of the stent with multidetector computed tomography), raises some questions. Indeed, the authors explained at the end of the Methods section that “the distance from the stent frame inflow to the aortic annulus (most basal insertion of the native aortic leaflets) was measured.” A proper assessment of the native annulus before TAVR is already a difficult and a still debated challenge; therefore, a proper assessment after TAVR seems very difficult or unfeasible. Indeed, when we made these measurements in our study (2), we clearly noted that post-implantation multi-detector computed tomography implies a complex mixture of artifacts associated with native calcifications and stent frame, particularly at the most basal insertion of the native aortic leaflets, which is not visible except when the stent frame is implanted in a high position. This is the reason why the implantation depth was evaluated in our study with reference to the floor of the sinuses of Valsalva.
Because this endpoint reflects the main result of their study, I think that the authors should precisely state, with a dedicated figure, the methodology used to measure the depth of implantation to ensure good reproducibility and comparability with previous and future studies on this interesting topic.
- American College of Cardiology Foundation