ASD was diagnosed when abnormal flow was recorded in right atrium. ASD was proved by surgery in 33 of 185 children with congenital heart disease, and all children had sugical correction of their heart deformities.

On pulsed Doppler echocardiographic exmination, abnormal flow was recorded in 32 of the 33 children with ASD and 3 of 152 children without ASD. This pulsed Doppler echocardiographic diagnosis of ASD by abnormal flow in right atrium has sensitively of 97% and specificity of 98%.

High correlation was found between the estimates of Qp/Qs ratio by Doppler and Fick method(r=0.90, P<0.01).

So we concluded that pulsed Doppler echocardiographic diagnosis of ASD was specific and sensitive method and careful pulsed Doppler echocardiographic examination may avoid the unnecessary cardiac catheterizetion in patients with ASD.