[Tissue concentrations of beta-methyl-digoxin in children]

Beta-methyl-digoxin concentrations in adipose, skeletal muscle and myocardial tissues, were studied in 8 patients undergoing by-pass surgery because of congenital heart disease. Correlation between doses/kg, plasmatic and tissue concentrations were analysed. We found statistically correlation between doses/kg and plasmatic concentrations; doses/kg and skeletal muscle concentrations (p less than 0.01); plasmatic and skeletal muscle concentrations (p less than 0.05). Concentrations was significantly greater in myocardial than adipose tissue before extracorporeal circulation (p less than 0.01); and significantly greater than adipose (p less than 0.01) and skeletal muscle (p less than 0.05) tissues after extracorporeal circulation. Extracorporeal circulation lessens adipose and skeletal muscle concentrations, but increases myocardial concentrations significantly (p less than 0.05). It is concluded, that the behaviour of beta-methyl-digoxin, in relation with tissue concentrations, is similar to digoxin.