The ailment is causing Martinez to suffer from dizziness and shortness of breath.
Martinez, 38, was taken to the hospital in June after suffering from a rapid heartbeat, dizziness and cold sweats. He went on the DL and missed two weeks before returning to regular playing time.
Martinez is hitting .255 this season with 10 home runs and 47 RBIs in 107 games. He is under contract through the 2018 season and has said he plans to retire next year.
In the corresponding move, the Tigers recalled JaCoby Jones from Triple-A Toledo. Detroit had optioned the outfielder to Toledo on Saturday.