[Cyclic nucleotides and creatine phosphokinase activity in children with cardiac arrhythmias].

Forty-one children with cardiac arrhythmias were examined. It was established that cardiac rhythm disorders in children were accompanied by an increase in the cGMP levels as well as a decrease in the cAMP content, CPK activity and the cAMP/cGMP ratio varying in relation to the form of arrhythmia and the nature of heart damage.