Mechanical Heart Valves in Children

Abstract

Longterm follow-up of 17 children, who consecutively underwent replacement of one cardiac valve with the Björk-Shiley prosthesis, is presented. The children's mean age was 8 years (range 4-12 years) and body weight 23.5 kg (range 15.0-38.4 kg) at the time of surgery 1970-80. Nine of the 17 operations (53%) were second-stage cardiac surgery. The operations comprised 2 aortic and 7 mitral valve replacements, 2 implantations of prosthesis in aortoventricular plasties (Konno's operation), 4 in the functional mitral orifice of transpositions (3 congenitally corrected and one operated on a.m. Mustard) and 2 valved conduits included in the repair of complex malformations. Two deaths were associated with surgery, but were not related to the valve prosthesis per se. One patient died 37 months postoperatively, due to mechanical valve failure (early and late mortality 12% and 6%, respectively). All survivors were followed at least two years, 9 were followed at least 5 years and 6 at least 10 years (mean 7.7 years). Anticoagulation was maintained without pertinent problems. There was one thromboembolic episode (0.87%/patient year). Two patients were re-operated because of “outgrown prosthesis” after 8 and 111/2 years. Morbidity otherwise was low and 9 patients (53%) had no complications at all. We conclude that the mechanical valve is a suitable substitute for a seriously diseased cardiac valve in childhood. However, if valve replacement is performed in early life, the later need of exchange of the outgrown prosthesis must be faced.