Surgical redo versus transseptal or transapical transcatheter mitral valve-in-valve implantation for failed mitral valve bioprosthesis

Background Redo surgical mitral valve replacement (SMVR) is the current standard of care for patients with failed bioprosthetic mitral valve (MV). Transcatheter mitral valve-in-valve replacement (TMViV) is arising as an alternative to SMVR in high risk patients. We sought to evaluate procedural safety, early and mid-term outcomes of patients who underwent transseptal TMViV (TS-TMViV), transapical TMViV (TA-TMViV), or redo-SMVR. Methods We identified patients with failed bioprosthetic MV who underwent TS-TMViV, TA-TMViV, or SMVR at four Italian Centers. Clinical and echocardiographic data were codified according to Mitral Valve Academic Research Consortium definition (MVARC), except for significant valve stenosis. Results Between December 2012 and September 27, 2019 patients underwent TS-TMViV, 22 TA-TMViV, and 29 redo-SMVR. TS-TMViV and TA-TMViV patients presented higher mean age and surgical risk scores compared with SMVR group (77.8 +/- 12 years, 77.3 +/- 7.3 years, 67.8 +/- 9.4 years,p < .001; STS PROM 8.5 +/- 7.2; 8.9 +/- 4.7; 3.6 +/- 2.6,p < .001). TS-TMViV procedure was associated with shorter intensive care unit time and total length of stay (LOS) compared with TA-TMViV and SMVR group. There were no differences in MVARC procedural success at 30-days (74.1, 72.7, and 51.7%,p= .15) and one-year all-cause mortality between groups (14.8, 18.2, and 17.2%,p= 1.0). MV mean gradient was similar between TS-TMViV, TA-TMViV, and SMVR groups at 30 days and 12 months. Conclusions For the selected patients, TS-TMViV and TA-TMViV are to be considered a valid alternative to redo-SMVR with comparable 1-year survival. TS-TMViV is the less invasive strategy and has the advantage of shortening the LOS compared with TA-TMViV.