Chris Bosh had 20 points and 19 rebounds, while Norris Cole added 18 points from the bench to help the Heat pull away with a 34-24 fourth quarter.
Carlos Boozer paced the Bulls with 21 points.
Tony Parker poured in 32 points as the San Antonio Spurs held off the Golden State Warriors for a 102-92 victory and a 2-1 series advantage.
The Spurs led 32-23 at the end of the first quarter and never trailed thereafter, though the Warriors did briefly level in the third and gave San Antonio more nervous moments when they pulled to within a point in the fourth.
Tim Duncan had 23 points and 10 rebounds for the Spurs, while Klay Thompson led the Warriors with 17 points.