Carolina is 1-1 in the preseason. The game was Nashville's preseason opener.
Nashville veteran J.P. Dumont opened the scoring at 9:18 of the opening period when he intercepted an attempted clearing pass on the right faceoff dot and beat Carolina goaltender Justin Peters with a wrist shot high to the stick side.
After scoring a career-high 29 goals in 2007-08, Dumont had just 16 in 2008-09 and 17 last season. O'Sullivan evened the game at 4:46 of the second period.
Nashville defenseman Cody Franson broke his stick on an attempted slap shot from the right point. Carolina's Zac Dalpe collected the puck and sent O'Sullivan in all alone on Predators goaltender Pekka Rinne.
O'Sullivan signed a one-year, two-way contract with Carolina last week. He scored 11 goals in 73 games with Edmonton last season.
That goal was the only blemish on an otherwise strong outing for Rinne, who stopped 17 of the 18 shots he faced before being replaced by Mark Dekanich midway through the game.
Samsonov gave the Hurricanes a 2-1 lead at 15:34 of the second on a power-play goal.
Erik Cole added an empty-net goal for the Hurricanes and Peters went the distance in goal for Carolina to earn the win.