Right heart enlargement and shunt

Our 18 year old daughter was diagnosed with a PFO after a bout of tachycardia.  This was found on a regular echo.  She then had a transcranial doppler, negative for PFO, and a TEE which showed no obvious PFO or ASD, but still showed right heart enlargement and a shunt, though trivial, on the bubble study. The valves are fine. Her cardiologist, from an excellent heart center, then ordered a CT scan for anamalous venous drainage, which her GP said was returned as negative.  She is to have a repeat TEE in a few weeks.  She has been an athlete all of her life and we were shocked to learn of her heart condition.  They say that it is abnormal for an 18 year old to have an enlarged right atrium and right ventricle and a small shunt.  What advice could you give us in pursuing this if the next TEE shows nothing, we feel so uncomfortable just accepting this if no obvious problem can be found.  She presently feels very well and has been given no restrictions.  We are so puzzled and worried as to her future heart heatlh. Thank you so much for taking our question.

[CCF-M.D.-MJM]

Hi PJgirl,

Sorry to hear about the confusion with your daughter.  It sounds like they are doing the right studies to address their concerns.  It is not uncommon to see a right to left shunt (bubbles going from the right atrium to left atrium) during a bubble study from a small patent foramen ovale (PFO).  They often are not apparent on TEE, only through bubble study.  Such a small shunt, however, would not cause enlargement of the right atrium and ventricle.  IF the second TEE is negative, they could consider doing an MRI to rule out right ventricular dysplasia (RVD), but she really doesn't have the symptoms of RVD from what you are describing.

You didn't mention her pulmonary blood pressure or her right ventricular systolic pressure (RVSP).  I am assuming this means she doesn't have pulmonary hypertension.

If she has symptoms of lightheadedness or passing out, I holter monitor or event monitor may help.  The record her heart rhythms over time.

Fortunately it sounds like they are doing the right things.

Good luck and thanks for posting.