The trans-septal approach in transcatheter mitral valve-in-valve implantation for degenerative bioprosthesis

BACKGROUND: Transcatheter Mitral Valve-in-Valve Implantation (TMViVI) has recently emerged as a novel therapy for degenerated mitral valve bioprosthesis. Re-operative mitral valve surgery is associated with a substantial risk of mortality and morbidity. The objective of this study was to describe the outcomes of transcatheter mitral valve-in-valve implantations in our cardiac center. METHODS: Twenty-two patients underwent the valve-in-valve procedure because of bioprosthesis degeneration from March 2017 to October 2018. Clinical, echocardiographic, procedural details and survival at follow up were assessed. RESULTS: Eight patients refused re-operative cardiac surgery while others were deemed a high risk for conventional re-operative sternotomy. All patients had TMViVI performed via a trans-septal approach, and the prosthesis was implanted successfully with immediate hemodynamic improvement in 20 patients. One patient had tamponade (4.55%), two had permanent pacemaker insertion (9.09%), two patients had a renal impairment (9.09%), and three patients had vascular complications (13.64%). There was one aborted procedure for the failure to cross the tissue valve with a transcatheter valve, and one patient was converted to an emergency mitral valve surgery. All patients were discharged in NYHA class I/II and NYHA class was markedly improved at one-year follow-up (p = 0.002). CONCLUSIONS: Trans-septal mitral valve-in-valve implantation can be performed safely for degenerative mitral valve bioprosthesis and with favorable early clinical and hemodynamic outcomes.