Background <p>Recent developments in transcatheter mitral valve repair (M-TEER) have expanded the indication for the procedure beyond conventional criteria to include patients with anatomically complex degenerative mitral regurgitation (DMR), but long-term outcomes are not well known.</p> Aims <p>To investigate outcomes by specific anatomical criteria in patients with severe DMR and complex valve anatomy enrolled in the prospective MitraUlm registry.</p> Methods <p>Clinical and echocardiographic 3-year outcomes of 304 patients with DMR and complex mitral valve anatomy, defined according to the CLASP IID registry criteria, were investigated. Outcomes were analysed separately for specific anatomical complexities.</p> Results <p>33.5% of patients had ≥ independent significant jets, 12% multisegmental prolapse, 12.3% mitral valve orifice area &lt; 4 cm², 10.9% commissural lesions with wide/multiple jets, and 10.1% large flail. Mitral regurgitation (MR) reduction ≤ 2 was achieved in 93.8% of patients at discharge and in 85.9% at 3-year follow-up. Patients with multisegmental prolapse and commissural lesions with multiple/wide jets had the lowest MR reduction at discharge. Compared to patients treated with MitraClip Generation 1–3, patients treated with MitraClip Generation 4 had significantly better post-procedural MR reduction (MR ≤ 1 in 74.3% vs 50.7%, <i>P</i> &lt; 0.001) and higher 3-year survival rates (80.2% vs 61.6%, Log Rank <i>P</i> = 0.002<i>)</i>. Postprocedural MR reduction to MR ≤ 1 was the strongest independent predictor of 3-year survival, whereas the presence of at least two anatomical complexities and elevated post-procedural left atrial pressure predicted 3-year all-cause mortality.</p> Conclusions <p>In patients with anatomically complex DMR, advances in procedural techniques for M-TEER have allowed successful treatment with sustained MR reduction and improved long-term survival.</p> Graphical abstract <p></p>