Objective:Depolarizing potassium cardioplegia has been increasingly linked to left ventricular dysfunction,arrhythmia,and microvascular damage.We tested a low potassium cardioplegic solution employing adenosine and lidocaine as the arresting,protecting,and preserving cardioprotective combination in the cardiac surgery of children.Methods:One hundred and thirty four patients (age:0.25 ~ 3 years) with congenital heart diseases were enrolled into the study.They were randomly allocated to three groups according to the cardioplegia used in myocardial protection.