▁the ▁natural ▁card iac ▁pac em aker ▁site ▁sh ifts ▁between ▁the ▁sino at rial ▁node ▁( SA ▁node ), ▁the ▁at ria , ▁and / or ▁the ▁at ri ov ent ric ular ▁node ▁( AV ▁node ). ▁This ▁sh ifting ▁of ▁the ▁pac em aker ▁from ▁the ▁SA ▁node ▁to ▁adjacent ▁t issues ▁is ▁ident ifiable ▁on ▁E CG ▁Le ad ▁II ▁by ▁morph ological ▁changes ▁in ▁the ▁P - wave ; ▁sin us ▁be ats ▁have ▁smooth ▁u pr ight ▁P ▁waves , ▁while ▁at rial ▁be ats ▁have ▁fl atten ed , ▁not ched , ▁or ▁di phas ic ▁P - w aves . ▁It ▁is ▁often ▁seen ▁in ▁the ▁very ▁young , ▁very ▁old , ▁and ▁in ▁athlet es , ▁and ▁rarely ▁causes ▁sympt oms ▁or ▁requires ▁treatment . ▁ ▁C ause ▁ ▁References ▁ ▁External ▁links ▁▁ ▁Category : Card iac ▁arr h ythm ia <0x0A> </s> ▁Ph ạ m ▁V ă n ▁Ti ế n ▁( born ▁ 3 0 ▁April ▁ 1 9 9 3 ) ▁is ▁a ▁Vietnam ese ▁footballer ▁who ▁plays ▁as ▁a ▁goal keeper ▁for ▁V . Le ague ▁ 1 ▁club ▁B ec ame x ▁B ì n h ▁D ư ơ ng . ▁ ▁Hon ours ▁ ▁International ▁ ▁Vietnam ▁U 2 3 ▁ ▁Third ▁place ▁: ▁S out heast ▁Asian ▁Games : ▁ 2 0 1 5 ▁ ▁References ▁ ▁Category : 1 9 9 3 ▁birth s ▁Category : L iving ▁people ▁Category : V ietnam ese ▁football