Xray. A study of the GI tract should be done to check that the rotation of the intestine is mirror image. If not then malrotation could exist and this should be treated with surgery.
Not aware of any. This is basically an anatomic anamoly that doesn't place the patient at any increased risk other than some puzzled looks from medical professionals when they do chest xrays and ekgs. Just be sure and always inform doctors/nurses prior to being seen for medical issues. You may have a slight chance of more sinus infections and lung infections due to disorders of the cilia.