Mitral Valve Replacement With the 15-mm Mechanical Valve: A 20-Year Multicenter Experience

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 (St Jude Medical, St Paul, MN).

A multicenter, retrospective cohort study was performed among patients who underwent mitral valve replacement with a 15-mm St Jude Medical Masters prosthesis at 4 congenital cardiac centers in The Netherlands. Operative results were evaluated and echocardiographic data studied at 0.5, 1, 2, 3, 5, and 10 years after surgery.

Surgery was performed in 17 infants. Ten patients (59%) were treated in the intensive care unit before surgery; 8 (47%) were on ventilator support. Median age at surgery was 3.2 months (interquartile range [IQR], 1.2-5.6), and median weight was 5.2 kg (IQR 3.9-5.7). There was 1 early cardiac death and 1 late noncardiac death. Median follow-up time was 9.6 years (IQR, 2.4-13.2), including 8 patients with a follow-up more than 10 years. The first prosthetic valve explantation (n = 11) occurred at a median of 2.9 years (IQR, 2.0-5.4). 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 mm Hg (at discharge) to a mean of 14.3 mm Hg (at 5-year follow-up).

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.