Temporal Changes in Procedural Success and Clinical Outcomes of MTEER by Mechanism of MR: Analysis of the STS/TVT Registry.

Background: With the expansion of indications for mitral transcatheter edge-to-edge repair into nondegenerative etiologies, it is unknown whether changes in technical success and clinical outcomes have occurred.

Methods: The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy (STS/TVT) registry was analyzed from 2013 to 2023. Patients in shock were excluded. Patients were grouped by the mechanism of mitral regurgitation (MR) and divided into time periods.

Results: Overall, 68 028 patients were included. The application of mitral transcatheter edge-to-edge repair has evolved over the past decade to include more nondegenerative etiologies-increasing from 19% to 43%. The biggest growth was observed in functional MR (atrial and ventricular). Excluding acute ischemic MR, the odds of technical success were significantly higher for all mechanisms compared with degenerative MR (DMR). Over time more procedures were performed using only 1 implanted device (64.7% during 2022-2023 versus 54.6% during 2013-2017), without negatively impacting technical success. In multivariable analyses, the risk of 1-year heart failure readmission for ventricular functional MR was not higher than for DMR (P=0.10642), while patients with chronic ischemic MR and atrial MR had a 19% higher risk of 1-year heart failure readmission compared with DMR (P=0.00493) even if they had a successful procedure. However, the risk of 1-year mortality was not higher in nondegenerative etiologies compared with DMR. There was no statistically significant interaction between MR mechanism and time in outcomes analyses, indicating that the effect of MR mechanism on the technical and 1-year clinical outcomes did not vary significantly over time.

Conclusions: The application of mitral transcatheter edge-to-edge repair for nondegenerative etiologies increased considerably. While the odds of technical success were higher for all etiologies except acute ischemic MR, a similar 1-year mortality risk was observed in nondegenerative etiologies compared with DMR in real-world settings. These data support the use of mitral transcatheter edge-to-edge repair in degenerative and nondegenerative etiologies.