More questions about son with extra heart beats

What I originally meant to ask was, Wouldnt the Echocardiogram (that results were "structurally normal") show any extra path ways in my Sons heart? We werent told of it when he had it done. The cardiologist diagnosed this on Friday by the looks of my sons 6 month routine EKG. Can it be diagnosed by an EKGand not a Echocardiogram? What is it that tells him that there is an extra path? ? Is this something that does require treatment if he does in fact have an extra path way? Our cardiologist is forwarding my sons information to an Electrophysiologist.
Thanks again for any responses!
Tonya in Hawaii

[CCF CARDIO MD JMF]

Dear Tonya,

the echo gives results about the pumping chambers and valves in the heart.  Only an EKG will show this extra pathway.  Please keep us posted on the evaluation by the electrophysiologist.