Dextrocardia without Situs Inversus

My 12 year old daughter was diagnosed with dextrocardia without situs inversus as an infant, after a routine chest x-ray.  All the normal tests were done, ECG, echocardiagram, etc.  It was determined that she did not have Kartagener’s or any other complications related to the dextrocardia.

However, I was told she needed to be monitored by the cardiologist approximately every 5 years to make sure the blood flow to her organs, all of which are in the "normal" places, was continuing to be effective as her body grew.

Recently she has had several fainting spells, a problem since she was a young child, but always in the past related to external stressors.  Lately they are happening more frequently, though, and with no known cause.

We were sent to the ER yesterday where the focus was on her heart defect.  The ECG came back normal and he were refered to the cardiologist for further testing.  No blood tests or CT scans were performed, so at this point I'm not convinced that it has nothing to do with her heart.

My question is this:  Could the fainting spells be an indication of new complications of the dextrocardia?  Should I insist on blood work and possibly a CT scan to pursue other possible causes of the fainting?

Thank you.