Transcatheter edge-to-edge mitral valve repair in patients with mitral annulus calcification

BACKGROUND: MAC is commonly found in patients affected with MR, and it is associated with high morbidity, mortality and worse cardiac surgical outcomes. Transcatheter edge-to-edge repair could be an alternative treatment, although there is little evidence in this population. AIMS: The aim of this study was to analyse the safety, efficacy and durability of MitraClip implantation in patients affected with mitral regurgitation (MR) and mitral annulus calcification (MAC). METHODS: We analysed the outcomes of 61 suitable patients affected with severe MR and moderate or severe MAC (the "MAC" group) and 791 patients with no or mild MAC (the "NoMAC" group) treated with the MitraClip device. RESULTS: Procedural success was similar (91.8% vs 95.1%, p=0.268, in MAC and NoMAC, respectively), with a very low rate of complications. At one-year follow-up, 90.6% of MAC and 79.5% of NoMAC patients had MR grade ≤2 (p=0.129), 80% in both groups remained in NYHA Functional Class ≤II, and a significant reduction in cardiac readmissions was observed (65% vs 78% in MAC vs NoMAC, p=0.145). One-year mortality tended to be higher in MAC patients (19.7% vs 11.3%, p=0.050), with no difference in cardiovascular mortality (15.3% vs 9.2%, p=0.129). CONCLUSIONS: MitraClip use in selected patients with moderate or severe MAC is safe, feasible and achieves good clinical and echocardiographic results at one-year follow-up.