"President Gerald R Ford successfully underwent an angioplasty procedure on Thursday at Mayo Clinic in Rochester, Minnesota," his secretary and chief of staff, Penny Circle, said in a statement.
"During the procedure, stents were placed in two of his coronary arteries in order to increase the blood flow through those arteries," Circle said.
Stents help prevent arteries from becoming blocked.
"Following the operation, President Ford returned to his room at Mayo Clinic and is resting comfortably with his wife Betty and family," Circle said.
The operation came four days after President Ford, 93, underwent surgery to implant a pacemaker that will improve his heart's performance.
Before going to the Mayo Clinic, he had been admitted to a medical centre in Vail, Colorado, for two days in late July after experiencing shortness of breath at his home in Beaver Creek.
The oldest living former US president suffered a stroke in 2000, and was briefly admitted to a hospital again in May 2003 after nearly collapsing during a round of golf in the intense heat of the California desert.
Ford became the 38th president in 1974, after Richard Nixon resigned rather than face impeachment in Congress as a result of the Watergate scandal.