Growth of children with a functionally single ventricle following palliation at moderately increased altitude

The bidirectional Glenn and Fontan procedures are empirically performed as interim and definitive procedures in children with a functionally single ve ntricle. The optimal stage of palliation, nonetheless, remains unknown. Dur ing childhood, growth is a fundamental measure of response to therapy. Grow th may be influenced by the degree of cyanosis, the volume load on the vent ricle, and cardiac performance. Thus, the weight and stature of children wi th a functionally single ventricle who underwent a bidirectional Glenn proc edure or a Fontan procedure were studied to determine the effect of each in tervention on growth. Z scores for weight and stature were retrospectively determined prior to palliation, at yearly intervals for 4 years, and from l ong-term measurements until 18 years of age in all patients with at least 2 years of observation following palliation. Growth was evaluated in 54 pati ents with a bidirectional Glenn procedure, and 65 patients with a Fontan pr ocedure. The Z scores for weight were improved after each method of surgica l palliation. Stature, however, was improved only following the bidirection al Glenn procedure. Growth was impaired in patients who developed protein l osing enteropathy. Weight improved only during the initial 2 years after th e Fontan procedure in patients who had a surgical fenestration. Over the lo ng-term, patients who underwent a Fontan procedure were more likely to have a Z score less than -2.0 for weight and stature than patients who underwen t only a bidirectional Glenn procedure. Late mortality and the incidence of heart transplantation were increased in patients who experienced a decreas e in their rate of growth, defined as a negative change of more than one Z score in weight or stature, following the Fontan procedure. In conclusion, at moderately increased altitude, children with a functionally single ventr icle grow more appropriately following the bidirectional Glenn procedure th an following the Fontan procedure. A decrease in the rate of growth is asso ciated with a poor prognosis following the Fontan procedure.