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.

Streptococcus bovis prosthetic valve endocarditis associated with silent colonic carcinoma.

A 75-year-old woman was admitted to our hospital with a 3-month history of fever. Of note, she had a bioprosthetic mitral valve replacement 1 year prior to admission. Streptococcus bovis was isolated from three sets of blood cultures. An echocardiogram showed a flickering mass attached to the bioprosthesis. Her blood culture became sterile by the fourth day of ceftriaxone therapy. In spite of the absence of gastrointestinal symptoms, screening colonoscopy revealed an invasive colonic adenocarcinoma. The association linking S. bovis endocarditis and colonic tumours is well recognised. However, despite early reports of this association by Klein et al in 1979, a large number of practising physicians remain unaware of this phenomenon. This lack of awareness results in lost opportunities for early diagnosis and, consequently, improved outcome in such patients. Our report emphasises this association in an area with a low incidence of S. bovis endocarditis.