Rio's Organising Committee said in a statement that the 69-year-old Nuzman, a member of the International Olympic Committee (IOC), had checked himself into a hospital late Tuesday (June 14) after a routine health exam showed an abnormal heart rhythm.

Detailed exams yesterday showed Nuzman's rhythm had returned to normal and he was expected to leave the intensive care at the Samaritano Hospital, in Botafogo, later today.

"The patient arrived at the hospital on Tuesday at 21 hours, with a case of cardiac arrhythmia, and was taken to the ICU," a statement from the hospital said.

"At the moment, Nuzman is stable and we are performing a series of tests."

He is expected to be released tomorrow, Rio 2016 said.

"The heart arrhythmia clinical status is already reversed," a spokesman said.

Nuzman is a lawyer is a former volleyball player who played for Brazil at Tokyo in 1964 when the sport made its Olympic debut.

He has been President of the Brazilian Olympic Committee (COB) since 1995 and was the driving force behind Rio's successful bid to host the 2016 Olympics and Paralympics, the first time the Games will be staged in South America.

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