▁ ▁p ector alis ▁Category : F ish ▁described ▁in ▁ 1 8 6 1 <0x0A> </s> ▁C ai u á ▁is ▁a ▁municipality ▁in ▁the ▁state ▁of ▁São ▁Paulo ▁in ▁Brazil . ▁The ▁population ▁is ▁ 5 , 8 0 0 ▁people ▁( 2 0 1 8 ▁estimate ) ▁in ▁an ▁area ▁of ▁. ▁The ▁elev ation ▁is ▁ 3 7 5 ▁m . ▁ ▁References ▁ ▁Category : M unicip al ities ▁in ▁São ▁Paulo ▁( state ) <0x0A> </s> ▁At rial ▁sept al ▁defect ▁( AS D ) ▁is ▁a ▁con gen ital ▁heart ▁defect ▁in ▁which ▁blood ▁flows ▁between ▁the ▁at ria ▁( upper ▁ch amb ers ) ▁of ▁the ▁heart . ▁ ▁Some ▁flow ▁is ▁a ▁normal ▁condition ▁both ▁pre - b irth ▁and ▁immediately ▁post - b irth ▁via ▁the ▁for amen ▁ov ale ; ▁however , ▁when ▁this ▁does ▁not ▁naturally ▁close ▁after ▁birth ▁it ▁is ▁referred ▁to ▁as ▁a ▁pat ent ▁( open ) ▁for amen ▁ov ale ▁( P FO ). ▁It ▁is ▁common ▁in ▁patients ▁with ▁a ▁con gen ital ▁at rial ▁sept al ▁an eur ys m ▁( AS A ). ▁ ▁After ▁P FO ▁closure ▁the ▁at ria ▁normally ▁are ▁separated ▁by ▁a ▁div iding ▁wall , ▁the ▁inter at rial ▁sept um . ▁If ▁this ▁sept um ▁is ▁defect ive ▁or ▁absent , ▁then ▁o xygen - rich ▁blood ▁can ▁flow ▁directly ▁from ▁the ▁left ▁side ▁of ▁the ▁heart ▁to ▁mix ▁with ▁the ▁o xygen - po or ▁blood ▁in