Police arrested Hickey in a dawn raid on his hotel on Wednesday, in connection with an investigation into the illegal resale of Olympics tickets.
The 71-year-old was admitted to Samaritano hospital for chest pain after his arrest, but released the next day into custody.
International Olympic Committee (IOC) member Patrick Hickey (R) arrives at the police station after being arretsed on allegations of taking part in a black market ticket ring, on August 18, 2016, in Rio de Janeiro, Brazil.
Europe's top Olympic official, Ireland's Pat Hickey, has had an appeal for bail denied by a Brazilian judge and has been taken to Bangu maximum security prison in Rio de Janeiro.