Medium-term follow-up of mechanical valves inserted in children

OBJECTIVE: We reviewed our experience with mechanical valves inserted between 1988 and 2002 in children aged 15 years or younger.

METHODS: Hospital files were extracted retrospectively. Follow-up was completed by March 2005.

RESULTS: Of 41 patients, we inserted a valve in atrioventricular position in 27 children, having a median age of 3.1 years, ranging from 0.4 to 14.5 years, and in aortic position in the remaining 14, having a median age of 13.5 years, and a range from 7.0 to 14.9 years. For the valves inserted in atrioventricular position, the underlying disease was congenital in 23, rheumatic in two, post-endocarditic in one, and Marfan's syndrome in one. Mean follow-up was 7.7 years, with standard deviation of 5.3, giving a total follow-up of 209 patient years. Mortality at 30 days was 7%, and survival was 73% at up to 16 years follow-up. Events related to anticoagulation were seen in 3 patients, corresponding to 1.4% per patient year. In 6 patients (22%), heart block ensued which required implantation of a pacemaker treatment, and 5 patients (19%) had reoperations. For the implantations in aortic position, the underlying disease was congenital in 13, stenosis in 10 and insufficiency in three, and post-endocarditis in one. Mean follow-up was 6.8 years, with standard deviation of 4.6, giving a total of 95 patient years. We lost one patient within 30 days (7.7% mortality), and survival was 77% at up to 13 years follow-up. There were no incidents of thrombosis, nor events related to anticoagulation, but one patient (7%) needed insertion of a pacemaker due to a perioperative heart block, and one (7%) required new valvar replacement.

CONCLUSIONS: Although preferably avoided, mechanical valves can be implanted in children with an acceptable mortality and morbidity, and good long-term results.