Nine children (aged 1.2-15 years) have been treated with mechanicalcirculatory support devices at our institution. Indications for treatmentwere acute cardiac allograft rejection (n = 4), postcardiotomy cardiogenicshock (n = 4), and bridge to cardiac transplantation (n = 1). Eightpatients required left ventricular support, and one required biventricularsupport. A BioMedicus centrifugal pump was used in eight patients, and aHemopump intra- aortic axial flow device was used in one patient. In twopatients, an intra-aortic balloon pump was in place at the time thatcirculatory support was instituted. Mechanical support time ranged from 2to 139 h, and the average flow index was 2.31 l/min per m2. Three patientsrequired hemodialysis during support, and one patient required re-exploration because of mediastinal hemorrhage. Recovery of nativeventricular function was assessed by transthoracic or transesophagealechocardiography, and weaning from the device was achieved by graduallydecreasing pump flow in increments of 0.1 to 0.5 l/min. Seven patients weresuccessfully weaned from support. Two hospital deaths occurred aftercirculatory support had been discontinued: one patient died of respiratoryfailure and the other of gram-negative pneumonia and sepsis. The fivesurviving patients experienced no significant complications, and theirhemodynamic indices were normal at the time of discharge. At a meanfollow-up of 28.8 months, these patients are leading active unrestrictedlives, with no long-term device-related sequelae. Based on this experience,mechanical circulatory support is feasible in children who experienceprofound circulatory failure from a variety of causes.