死而后已 [- - hòu yǐ]do one's best till one's heart ceases to beat; If that leads to death, so be it.; Only with death does one's course end.; to the end of one's days; until one's death:
•¶ 他真是鞠躬尽瘁，死而后已。 He really gave his all till his heart ceased to beat.