question about detecting PFO's

I have been reading this board for awhile now, gathering information because my 21 year old daughter has suffered from migraine headaches since first grade(now in her third year of college).  We've been to pediatricians, neurologists, general internists, massage therapists, orthodontists and now to a headache center.  It seems that we never  really get significant relief( she has a bad headache at least once a week). At her Dec. visit to the headhache center, however, the neurologist noticed a rapid heart rate and high blood pressure.  We were immediately sent to the cardiologist who ran an EKG, bloodwork, and an echocardiogram along with his clinical exam.  Although, her vital numbers were a little high, he seemed to brush it off.  Her echo and bloodwork showed nothing.  I was wondering if a PFO would have shown up on the echo?  Did others with PFO's have symptoms?  She is on Zanaflex, Cymbalta and Inderal (prescribed by the cardiologist).  I actually think that I have noticed an improvement since she started the Inderal.  I also am trying to get used to the fact that she is only 21 and on so much medicine although I don't want her having the headaches, either.  I was wondering if the normal echo would rule out the possibility that a PFO could have been causing the headaches all of these years?

Your answer was not longwinded and very informative...Thank you so much for your thoughtful response.  I am so glad that you found your cause and now have relief!

I plan to follow up with her regular doctor her in town.  You've given such helpful information.  We travel to a well respected medical center a few hours from our home.  Like I said, our neurologist was concerned and could not get us to the cardiologist fast enough.  I was suprised when although her blood pressure, heart rate and EKG numbers were "a little high", especially for a 21 year old, that they weren't more concerned like the neurologist was.  I will see about having the echo that you described done here in town.  It certainly would answer a lot of questions and explain why we've had limited success all of these years with preventatives and relief.  I am so glad that your neurologist pushed forward and I think it is definitely worth looking into for us,too. Thanks again!