Efficacy and safety of transcatheter valve-in-valve replacement for Mitroflow bioprosthetic valve dysfunction.

OBJECTIVES: Bioprostheses with pericardial leaflets mounted externally on the stent pose a high risk for valve-in-valve (ViV) procedures. This study analyzed the efficacy and safety of ViV procedures for treating structural valve deterioration (SVD) in Mitroflow bioprostheses.

METHODS: Between January 2012 and August 2017, 11 patients (mean age 80.3 ± 5.6 years) were treated for SVD of Mitroflow bioprostheses with transcatheter ViV procedures (six transapical [TA] and five transfemoral [TF]) using balloon expandable bioprostheses.

RESULTS: All patients but one were in NYHA class III-IV. Mean STS PROM, euroSCORE I, and euroSCORE II were 8 ± 6.5%, 27.8 ± 11.5%, and 12 ± 5.9%, respectively. Two patients had a "porcelain aorta." The size of implanted valves were 23 mm in 10 cases and 26 mm in one case. One patient suffered a coronary occlusion during a TF approach. The mean volume of contrast used in TF implants was 163 ± 69.8 mL. No contrast media were used in TA procedures. There was one in-hospital death (10%). At 1 year of follow-up, peak and mean aortic gradients were 25.5 ± 5.8 mmHg and 15.5 ± 5.7 mmHg, respectively. One patient had mild paravalvular regurgitation. Cumulative survival was 90.9% at 1 year, 70.7% at 2 years, and 53% at 3 years.

CONCLUSIONS: ViV procedures with balloon-expandable aortic valves provide good hemodynamic and clinical mid-term results for treating patients with a degenerated Mitroflow aortic bioprosthesis. Special care must be taken in small aortic roots, when the stented valve is in the supra-annular position to avoid coronary ostial obstruction.