The fourth-seeded Indian triumphed 3-2 (11-13 11-8 11-5 3-11 12-10) in a see-saw battle.
The world number 27 Chinappa rallied after losing the opening game which was dominated by Heba.
The Indian raced to an 8-3 lead in the second game before pocketing it easily. She built on the advantage by claiming the third game as well before Heba roared back in the fourth.
The Egyptian's fightback made the fifth game an exciting affair in which momentum kept swinging both ways.
But just when it seemed that Heba would walk away with the title, Chinappa got her act together and reeled off five back-to-back points to quite literally snatch victory from the jaws of defeat.
Chinappa's triumph marks the second consecutive year of an Indian winning the trophy with Dipika Pallikal being the one to clinch it before her.