Pneumatic pulsatile ventricular assist devices in children under 1 year of age

Although considerable progress has been made on ventricular assist devices (VAD) for adults, pneumatic pulsatile circulatory support in young infants is still limited. There is a need for long-term ventricular assist devices to bridge the failing myocardium of young children until recovery or transplantation. Miniaturized devices and innovative modalities need to be optimized. We report on our experience.

From 1/1992 to 6/2004, 18 infants (6 male/12 female) under 1 year of age were treated with the Berlin Heart Excor VAD. The infants were divided into two groups, depending on the year of treatment. Group A consists of eight infants resuscitated and supported with a pulsatile pneumatic ventricular assist device between 1992 and 1998 and group B consists of 10 infants treated between 1999 and 6/2004. With the pediatric-sized Berlin Heart we used miniaturized extracorporeal pneumatically driven blood pumps, the lowest stroke volume being 10 ml.

In 18 children, age 3-345 (median 147) days, artificial replacement of heart function was applied for long-term support (1-64, median 10 days) as a life-saving measure in our hospital. Nine had LVAD and nine BVAD support. All were in cardiogenic shock with multiorgan failure; three had fulminant myocarditis, four cardiomyopathy, and one chronic stage of congenital heart disease. Five children were weaned from the system, three reached heart transplantation, and 10 died on the VAD. There were no differences between groups A and B regarding age, body weight or diagnosis, but the duration of mechanical support differed: Group A, median 2, range 1-16 days; group B, median 12, range 1-100 days. Since 1999 (group B), the survival rate of our small infants has increased to 70% whereas none of the infants in group A survived to be discharged.

The outcome of VAD support in small infants is no longer inferior to that of adult support, now optimized cannulas, modified anticoagulation and optimized surgical and intensive care management have been established.