Long-Term Outcomes after Transcatheter Edge-To-Edge Repair in Patients with Anatomically Complex Degenerative Mitral Regurgitation improved significantly over the past decade

Background: Patients with anatomically complex degenerative mitral regurgitation (DMR) are increasingly being treated with transcatheter edge-to-edge valve repair (M-TEER) in high-volume centers, but their long–term outcomes are not well known.

Objective: To investigate trends in long-term outcomes in prohibitive surgical risk patients with symptomatic severe DMR and complex valve anatomy enrolled in the prospective MitraUlm registry between 2010 and 2020.
Methods: Clinical outcomes (median time of 1306 days) of 192 patients with severe DMR and complex mitral valve anatomy defined according to the MitraClip instructions for use were investigated. The study compared patients treated before 2017 with those treated after 2017.

Results: The prevalence of anatomically complex DMR (37% ≥2 independent jets,13.5% mitral valve orifice area <4 cm², 11.5% commisural lesion) increased significantly from 40.5% in the cohort treated before 2017 to 50.8% in patients treated afterwards, p=0.047. Patients treated after 2017 presented better clinical and hemodynamic status at baseline than patients treated before 2017 (NYHA class IV 21.2% vs 36.7 %, p=0.024, systolic pulmonary artery pressure 52 ± 15 mmHg vs 61 ± 18 mmHg, p=0.010). Post-procedural results improved significantly over time (post-procedural MR grade ≤1 in 58.3% of patients treated after 2017 vs. 41.7 % in patients treated before 2017, p= 0.032). All-cause 3-year mortality rates in patients with anatomically complex DMR decreased significantly over the last decade (45% before 2017 to 28.8% after 2017, p=0.041). Post-procedural left atrial pressure >20 mmHg (OR 3.25, 95%CI 1.84-4.33, p=0.007) and transmitral gradient >5 mmHg (OR 2.84, 95%CI 1.41-4.21, p=0.006) are the main independent predictors of long-term mortality, whereas the presence of at least two anatomical complexities (OR 2.55, 95%CI 1.38-4.71, p=0.005) predicts increased reintervention in patients with anatomically complex DMR. 

Conclusion: The prevalence of patients with anatomically complex DMR treated with M-TEER increased significantly over the past decade. Patients with anatomically complex DMR are now being treated earlier in the course of disease and benefit from improved post-procedural results and lower 3-year mortality rates compared to patients treated in the early stages of M-TEER.