Aldridge played 23 minutes and recorded 12 points, three rebounds, two assists and three blocks in his final NBA game, a 126-101 loss to the Los Angeles Lakers on Saturday, April 10.
"Today, I write this letter with a heavy heart. My last game, I played while dealing with an irregular heartbeat," Aldrige wrote in the post. "Later on that night, my rhythm got even worse which really worried me even more.
"The next morning, I told the team what was going on and they were great getting me to the hospital and getting checked out. Though I'm better now, what I felt with my heart that night was still one of the scariest things I've ever experienced.
"With that being said, I've made the difficult decision to retire from the NBA. For 15 years, I've put basketball first, and now, it is time to put my health and family first."
Aldrige made seven All-Star appearances and was a five-time All-NBA selection during his 15-year career, which was spent with the Portland Trail Blazers (2006-15) and San Antonio Spurs (2015-21), before joining the Nets in March.
Aldridge retires as the Blazers' all-time leading rebounder (5,434) and ranks third in career points (12,562) after being selected No. 2 overall by Portland in the 2006 NBA Draft.
The former University of Texas standout averaged 19.4 points, 8.2 rebounds, and 2.0 assists for his NBA career.