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

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.

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.

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.

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.