Is some of the underground tuber exposed and damaged? If not then I would just nature run its course, clean up the dead stuff off the floor a few weeks and then remove any dead or ugly stems after the plant has decided what stays and what goes.

They tend to drop leaves and leaflets all thru winter, espescially if facing harsh temps, as most aroids seem to do.

i'd be concerned that 'the stem' without leaves might rot. it might be better to cut it off to healthy tissue. i let mine shrivel when it happens(the top part) and then cut off right at the base. 'cause i don't like the site of stubs. just let the cut dry up - may be dust with cinnamon to prevent rot setting in.
depending on how your plant is doing, i'd pop it out of the pot to see the condition of tubers and check for any mushy parts.