Weinstein can't walk steadily and doesn't have a walking frame in jail. During his trial, he used a walker to get in and out of court.
After the movie mogul was convicted of sex crimes on February 24, he was taken to Bellevue Hospital in Manhattan with a heart issue.
The 67-year-old had a heart operation last week during which doctors put in a stent, Engelmayer told CNN.
He was then moved to the infirmary unit at Rikers Island.
It's expected he will be sentenced on March 11 in New York State Supreme Court, facing at least five years and a maximum of 20 years in jail.
The New York jury convicted Weinstein of committing a criminal sex act in the first degree involving one woman and another count of rape in the third degree.