At the beginning of World War II, he won a Rockefeller Foundation scholarship to Harvard Medical School and graduated with an MD in 1943.
In 1950, John McMichael recruited Shillingford to the Royal Postgraduate Medical School in Hammersmith.
Shillingford's research team studied the narrowing of the arteries that occurs with aging.
[1] He headed the Medical Research Council's cardiovascular unit, and his engineering interests and skills led to several diagnostic innovations.
[2] His major contributions were in the study and care of patients in the acute stages of heart attack, at a time when little was offered beyond pain relief.