Local authorities say the incident took place early yesterday morning at the 1600 block of Amanda Street.
The man's ex-girlfriend had unexpectedly arrived at his house and a verbal altercation ensued.
At one point the man left to retrieve his shotgun, only to be met with resistance from his current girlfriend upon his return.
She was rushed to the hospital in critical condition, but her status has since been upgraded to "stable."
Police were initially unsure if the man would be charged with a crime, but have since decided to arrest him on suspicion of aggravated assault.