Shortly after the death of Aristotle Onassis, his daughter Christina and his close associates, implemented his will and founded the Alexander S. Onassis Public Benefit Foundation. One of the Foundation’s objectives was the establishment of a modern Cardiac Surgery Center. This work was necessary because even though cardiac surgery had already begun to take place in Greece at the time, the capacity of state hospitals could not meet the needs of the Greek population, resulting to large numbers of patients travelling abroad.

The main objective of the Public Benefit Foundation Alexander S. Onassis was the creation of an exemplary cardiac surgery unit in accordance with the specifications of the most prominent centers abroad. Consequently, a large part of the total cost of the project was devoted to supplying the Centre with the most advanced technical means of operation and the most modern scientific instruments.

Construction began in October 1987 and was completed after five years, on October 6, 1992, when the hospital was officially donated to the Greek State. The Onassis Cardiac Surgery Center is located at the end of Syngrou Avenue (Syngrou 356) in an area of 8,000 sq.m. and the original investment reached a total of $ 75 million.