Mitral valve replacement with the 15-mm mechanical valve: a 20-year multi-center experience

Abstract Background The aim of this study was to evaluate early and long-term outcomes (mortality and prosthetic valve replacement) after mitral valve replacement with the 15-mm St. Jude Medical prosthesis. Methods A multicenter, retrospective cohort study was performed among patients who underwent mitral valve replacement with a 15-mm SJM Masters prosthesis at 4 congenital cardiac centers in The Netherlands. Operative results were evaluated and echocardiographic data were studied at 0.5, 1, 2, 3, 5 and 10 years after surgery. Results Surgery was performed in 17 infants. Ten patients (59%) were treated on the intensive care unit prior to surgery and 8 (47%) of them were on ventilator support. Median age at surgery was 3.2 (IQR 1.2 – 5.6) months, median weight was 5.2 (IQR 3.9 – 5.7) kg. There was 1 early cardiac death and 1 late non-cardiac death. Median follow-up time was 9.6 (IQR 2.4 – 13.2) years including 8 patients with follow-up > 10 years. First prosthetic valve explantation (n=11) occurred at median time of 2.9 (IQR 2.0 – 5.4) years. Other reinterventions were permanent pacemaker implantation (n=3), subaortic stenosis resection (n=2) and paravalvular leak repair (n=1). Prosthetic valve gradients increased from a mean of 5.0 (at discharge) to a mean of 14.3 (at 5 years follow-up) mm Hg. Conclusions Mitral valve replacement with the 15-mm prosthesis can safely be performed in infants and even in neonates. Median freedom from prosthesis replacement for outgrowth is 3.5 years. Thromboembolic complications were rare.