A surgical team at St. Joseph's Hospital and Medical Center in Phoenix performed the procedure Monday.
A hospital spokeswoman says Michaels is recuperating and remains in the hospital's intensive care unit for observation.
Doctors discovered the hole in Michaels' heart in April when he was treated for a brain hemorrhage.
Doctors inserted a catheter into a vein in Michaels' groin with a closure device, and tiny cameras assisted doctors as they operated to close the hole.
The closure device will remain in Michaels' heart permanently to stop abnormal blood flow between two chambers of his heart, which is thought to have caused the warning stoke he suffered.
