I like the comments:
-they should have done heart enzymes (I’m sure they did, that is standard of care even on those that they are 99.9% certain it is heartburn.)
-they should have kept him even just for an abnormal ekg (what if that was his normal and the hospital knew that?)
-”I was always under the impression when you had chest pains they keep you overnight for observation.” (Not if they have already ruled out any reason for staying. Or if they have already figured out the cause pneumonia, trauma, and heartburn are all causes of chest pain that don’t necessarily need hospitalization in all patients.)

http://online.wsj.com/article/SB10000872396390444620104578008263334441352.html

” As I rotated through other hospitals during my training, I learned that many hospitals have a “Dr. Hodad” somewhere on staff (sometimes more than one). In a business where reputation is everything, doctors who call out other doctors can be targeted. I’ve seen whistleblowing doctors suddenly assigned to more emergency calls, given fewer resources or simply badmouthed and discredited in retaliation. For me, I knew the ramifications if I sounded the alarm over Dr. Hodad: I’d be called into the hospital chairman’s office, a dread scenario if I ever wanted a job. So, as a rookie, I kept my mouth shut.”

. . .

“Without telling his partners, Dr. Rex began reviewing videotapes of their procedures, measuring the time and assigning a quality score. After assessing 100 procedures, he announced to his partners that he would be timing and scoring the videos of their future procedures (even though he had already been doing this). Overnight, things changed radically. The average length of the procedures increased by 50%, and the quality scores by 30%. The doctors performed better when they knew someone was checking their work.”

The author is a surgeon.