[1][2] McCarthy was raised in Palos Park, Illinois, as the youngest of eight sons in an Irish Catholic family.
[3] McCarthy obtained his medical degree at the Loyola University Stritch School of Medicine in 1980.
[3] In 2004, McCarthy moved back to Chicago and joined the Northwestern University Feinberg School of Medicine as the first Heller-Sacks Professor of Cardiothoracic Surgery and executive director of the new Bluhm Cardiovascular Institute, which had been created with a $10 million donation from billionaire philanthropist Neil Bluhm.
[7] Two patients brought a lawsuit against McCarthy, accusing him of experimenting with the ring on them without their knowledge and concealing evidence of complications.
McCarthy was found not guilty after the jury decided that the charges brought by the patient had no merit.