▁of ▁these ▁facts ▁make ▁finding ▁statist ically ▁significant ▁relationships ▁between ▁P FO ▁and ▁mig raine ▁difficult ▁( i . e ., ▁the ▁relationship ▁may ▁just ▁be ▁chance ▁or ▁coinc idence ). ▁In ▁a ▁large ▁random ized ▁controlled ▁trial , ▁the ▁higher ▁pre val ence ▁of ▁P FO ▁in ▁mig raine ▁patients ▁was ▁confirmed , ▁but ▁mig raine ▁head ache ▁c ess ation ▁was ▁not ▁more ▁pre val ent ▁in ▁the ▁group ▁of ▁mig raine ▁patients ▁who ▁under w ent ▁closure ▁of ▁their ▁P FO s . ▁ ▁C aus es ▁ ▁Down ▁synd rome ▁– ▁patients ▁with ▁Down ▁synd rome ▁have ▁higher ▁rates ▁of ▁AS D s , ▁especially ▁a ▁particular ▁type ▁that ▁involves ▁the ▁vent ric ular ▁wall . ▁As ▁many ▁as ▁one ▁half ▁of ▁Down ▁synd rome ▁patients ▁have ▁some ▁type ▁of ▁sept al ▁defect . ▁ ▁Eb stein ' s ▁anom aly ▁– ▁about ▁ 5 0 % ▁of ▁individuals ▁with ▁Eb stein ▁anom aly ▁have ▁an ▁associated ▁sh unt ▁between ▁the ▁right ▁and ▁left ▁at ria , ▁either ▁an ▁at rial ▁sept al ▁defect ▁or ▁a ▁pat ent ▁for amen ▁ov ale . ▁ ▁F etal ▁alco hol ▁synd rome ▁– ▁about ▁one ▁in ▁four ▁patients ▁with ▁f etal ▁alco hol ▁synd rome ▁has ▁either ▁an ▁AS D ▁or ▁a ▁vent ric ular ▁sept al ▁defect . ▁ ▁Hol t – O ram ▁synd rome ▁– ▁both ▁the ▁o ste ium ▁sec und um ▁and ▁o ste um ▁prim um ▁types ▁of ▁AS D ▁are ▁associated ▁with ▁Hol t