"The procedure was uneventful and went as planned," the institute said in a statement.
Mahathir was admitted into the institute on Friday, the second time in as many months that he has been hospitalised.
Mahathir, who has a history of heart problems, was admitted on Dec. 16 before being discharged a week later.
(Reporting by Rozanna Latiff; Writing by Mei Mei Chu; Editing by Ana Nicolaci da Costa)