warmog on 15 lvl ryze

im playing ryze. at lvl 15 with stacked and and i have 3000 hp exactly but warmogs heart doesnt work this is propably caused by counting exact hp as doubble value and healtbar shows int value but can you make it work? btw i think ryze is sustain mage and warmog is my way to ahieve health sustain #mage should have high health pool with less armor /mr