"Mike approached cancer with the same vigor and tenacity that he approached any football game -- to win," Heimerdinger's wife, Kathie, said in a statement. "Even in the final minutes he never gave up -- that was our Dinger. He was a deeply devoted husband and father, loving son and brother, loyal friend and committed coach who loved the game and life."
Heimerdinger also leaves a daughter, Alicia, and a son, Brian.
Heimerdinger made the trip to Houston with the team for that Sunday's game and was greeted on the field before the game by his son, then an intern with the Texans. Heimerdinger maintained his duties for the rest of the season but was fired in February, one day after Mike Munchak succeeded Fisher as the Titans' coach.
"It was a tough deal and Dinger was a tough guy to the end, which is no surprise to those who knew what type of competitor he was," Fisher said in a statement, according to ESPN.com. "He was a man's man. No matter how weak he looked, how weak he sounded, he never had a complaint and fought this cancer as you would only expect him to fight it."
Heimerdinger helped coach Steve McNair to co-MVP of the NFL with Peyton Manning in 2003 during his first run in Tennessee, where he was offensive coordinator from 2000 to 2004. He spent 2005 as offensive coordinator of the New York Jets before rejoining Shanahan in Denver as assistant head coach in 2006 and 2007, when he helped develop quarterback Jay Cutler. Then it was back to Tennessee for three seasons as offensive coordinator.
Born in DeKalb, Ill., Heimerdinger was a wide receiver and a center fielder at Eastern Illinois University, where he received a degree in history. He was inducted into Eastern Illinois' Hall of Fame in 2008. He also earned a master's degree in administration from Northern Illinois.
Heimerdinger spent four years as a high school coach in Fox Lake and McHenry, Ill., in the late 1970s, then was a coach at the Air Force Academy, North Texas State, the University of Florida, Cal State-Fullerton, Rice and Duke.
The Associated Press contributed to this report.