Mirjam Keßler, Julia Seeger, Jochen Wöhrle, Wolfgang Rottbauer and Sinisa Markovic*
Objective: The MitraClip® NT (MC-NT) as an updated version aim to facilitate improved maneuvering of the guide catheter and more efficient leaflet capture due to technical improvements of the delivery system and clip material. We evaluate procedural results and 12-month clinical outcomes of the new MC-NT device and compare them with the previous MitraClip® MC.
Methods: We analyzed a total population of 231 patients from our Ulm - Transcatheter Mitral Valve Repair registry. To adjust for differences of baseline characteristics a propensity-score matching was performed (N=142). 30-day endpoints were analyzed in accordance with the Mitral Valve Academic Research Consortium (MVARC). For both devices 12-month clinical results (MACCE, mortality, and heart failure rehospitalization) were evaluated.
Results: Acute technical success was achieved in 100% with both device groups. Device, procedure and fluoroscopy time were comparable in both treatment groups. In-hospital mortality was 2.8% in the MC-NT group and 4.2% in the MC group (p=0.65). After 30 days single-leaflet clip detachment was observed in 2.8% in the MC-NT group compared to 1.4% (p=0.56). Mitral regurgitation was reduced to the same extent in both treatment groups (1.6 ± 0.6 vs. 1.6 ± 0.5 in MC-NT group, p=0.57) with comparable rates of recurrent moderate to severe mitral regurgitation after 30 days and during 12-month follow-up. Clinical results up to 12 months and improvement of New York Heart Association functional class were comparable in both device groups (3.1 ± 0.7 to 2.1 ± 0.9 vs. 3.2 ± 0.6 to 2.1 ± 0.9, p=0.75).
Conclusion: The new MitraClip® NT as an updated version presents itself as an efficacious and safe device, but all in all failed to prove superiority compared to the original MitraClip® in terms of procedural and clinical results.