The letter 'A' (when capitalized) bears resemblance to the inverted heart. This is a fact of which Thomas Pynchon was most certainly aware.

"The founders of a new colony, whatever Utopia of human virtue and happiness they might originally project, have invariably recognized it among their earliest practical necessities to allot a portion of the virgin soil as a cemetery, and another portion as the sight of a prison."

from The Scarlet Letter by
Nathaniel Hawthorne