childs bradycardia and murmur

My 12 year old daughter was found to have a slow heart rate (52) while at the same time a very distinct swishing sound was heard on the second beat.  She has had regular checkups over the years and nothing has ever been detected before.  What could bring this condition on at this time?  She is a very athletic child.  Because we are overseas and working thru a different language, I came to the conclusion myself that this was most likely classified as a heart murmur.  Please advise as to what you would consider should be done to further investigate this situation.  Thank you very much.

[CCF CARDIO MD JMF]

Dear Linda,

It is possible that your daughter may have developed a valvular abnormality or a shunt across two chambers in her heart.  The easiest way to assess this is through an echocardiogram.  This is a simple ultrasound based test.