Sessions made two free throws to pull the Bobcats to 89-87 with 1:38 left, but James passed to Bosh for a dunk to make it 91-87 with 1:13 on the clock.
Following a timeout, Kemba Walker missed a 3-pointer and James grabbed a rebound, then drove for a layup to give Miami a six-point lead with 37 seconds left. Charlotte got no closer than five points the rest of the way.
"They've been in those moments more than we we've had," Sessions said. "They made the plays and we couldn't make the stops we needed in the end."
Charlotte played without rookie small forward Michael Kidd-Gilchrist, who suffered a concussion against Houston on Saturday night. Kidd-Gilchrist will need to pass the NBA's post-concussion protocol before he'll be cleared to play.
NOTES: Charlotte's Byron Mullens had 12 points and nine rebounds in his return from an ankle injury that forced him to missing 19 games. "I'm still kind of concerned jumping off of it and getting hurt again.," he said, "but I just have to go out there and play with full confidence and not worry about it." ... Heat forward Shane Battier dunked for the first time in four years early in the second quarter. "I might release a DVD on that," he said. ... The Heat returned home to begin a five-game homestand after playing 10 of 12 on the road. ... James and Walker entered the game leading their respective team in scoring, assists and steals. The only other NBA players to lead their team in those categories were Golden State's Stephen Curry, Phoenix's Goran Dragic and Cleveland's Kyrie Irving.