Answer:
We can see that Poe foretells that the prince will not escape death forever. Three examples of this can be seen at:
In the description of the rooms, we can see that the last one, the seventh room, is decorated in black and has the windows stained with blood. This environment has elements that remind us of death and foreshadow that it will arrive at any moment.
Furthermore, when we are introduced to the appearance of people who are caught by the plague, we know that death is coming and that it will not be long.
Lastly, when the sequence of chambers from east to west, it symbolizes the end. This end is a harbinger of death.
Explanation:
:S