Dallas police are investigating after a man was stabbed in the heart outside a business in the Bishop Arts neighborhood.The victim, who is only 22 years old, is now in a coma and fighting for his life.The stabbing happened on Saturday just before 2 a.m. outside Dos Amigos in the 500 block of Madison Avenue.Police said there was a verbal argument inside the business. The suspect pulled out a knife, and the bouncers threw everyone out. The victim was stabbed when the fight continued outside. He was taken to a local hospital, and the suspect got away.Police did not release any information about or description of the suspect.Abraham Herrera’s family members told FOX 4 he was defending his girlfriend in the fight. They said she was insulted in the business and then slugged in the parking lot.He stepped up thinking it would be a fistfight and was stabbed in the chest."He was stabbed in the heart after the altercation continued.