Mitral valve replacement using a collar-reinforced mitral prosthesis for severe mitral annular calcification, which secures implantation in both the supra-annular and intra-atrial positions: a case report

BACKGROUND: Appropriate management of mitral annular calcification associated with mitral valve surgery must be determined on a case-by-case basis. However, an established procedure remains uncertain. CASE PRESENTATION: This report describes a surgical case of severe mitral and aortic valve stenosis associated with severe mitral annular calcification in a 71-year-old woman who underwent mitral valve replacement with a collar-reinforced mitral prosthesis. The patient underwent surgical repair after the treatment for heart failure. As the present patient was deemed to be at high risk for conventional mitral valve replacement, we applied a composite prosthetic valve that was enlarged circumferentially on the ventricular side of the prosthesis with a bovine pericardial patch. First, the solid calcium bar was left untouched and only the friable calcified mass that was easily scattered was removed. Subsequently, the prosthesis was secured by two mattress sutures placed in the intra-atrial position at the region of the extended calcified myocardium. Additionally, ten mattress sutures were placed in the supra-annular position at the other regions capable of passing stitches from the ventricular side to the atrial side. Finally, a 1.5 cm wide trimmed bovine pericardial collar was sutured circumferentially from the annulus to the atrial wall using running 4–0 polypropylene for reinforcement. Although temporary hemodialysis was performed for acute renal failure, the patient remained asymptomatic. CONCLUSIONS: The present case suggests that mitral valve replacement using a collar-reinforced mitral prosthesis may be an effective technique for severe mitral annular calcification. To avoid catastrophic complications associated with treatment for severely calcified annulus, it is crucial to make a prudent preoperative decision regarding the surgical strategy under circumstances where conventional mitral valve replacement is impossible.