▁the ▁heart ' s ▁mus cle ▁cells . ▁The ▁heart ' s ▁mus cle ▁cells ▁may ▁die ▁from ▁lack ▁of ▁o xygen ▁and ▁this ▁is ▁called ▁a ▁my oc ard ial ▁inf ar ction ▁( comm only ▁referred ▁to ▁as ▁a ▁heart ▁attack ). ▁It ▁leads ▁to ▁damage , ▁death , ▁and ▁event ual ▁sc arring ▁of ▁the ▁heart ▁mus cle ▁without ▁reg row th ▁of ▁heart ▁mus cle ▁cells . ▁Chron ic ▁high - grade ▁narrow ing ▁of ▁the ▁coron ary ▁ar ter ies ▁can ▁indu ce ▁trans ient ▁is chem ia ▁which ▁leads ▁to ▁the ▁induction ▁of ▁a ▁vent ric ular ▁arr h ythm ia , ▁which ▁may ▁terminate ▁into ▁a ▁dangerous ▁heart ▁rh ythm ▁known ▁as ▁vent ric ular ▁f ibr ill ation , ▁which ▁often ▁leads ▁to ▁death . ▁ ▁Typ ically , ▁coron ary ▁ar tery ▁disease ▁occurs ▁when ▁part ▁of ▁the ▁smooth , ▁el astic ▁l ining ▁inside ▁a ▁coron ary ▁ar tery ▁( the ▁ar ter ies ▁that ▁supply ▁blood ▁to ▁the ▁heart ▁mus cle ) ▁develop s ▁a ther os cl eros is . ▁With ▁a ther os cl eros is , ▁the ▁ar tery ' s ▁l ining ▁becomes ▁hard ened , ▁st iff ened , ▁and ▁accum ul ates ▁depos its ▁of ▁calci um , ▁fat ty ▁lip ids , ▁and ▁ab normal ▁infl am mat ory ▁cells ▁– ▁to ▁form ▁a ▁pla que . ▁Cal ci um ▁ph osph ate ▁( h ydro xy apat ite ) ▁depos its ▁in ▁the ▁mus