Mandatory heart screening should be introduced for all athletes taking part in competitive sports, doctors said.
Regular heart check-ups could dramatically reduce the number of athletes who die from sudden heart failure by identifying medical problems early on, according to a study in the British Medical Journal.
In Britain and across Europe heart screening has developed erratically. Some bodies, such as the International Olympics Committee, recommend check-ups for elite athletes but do not insist on them, while football associations such as Uefa are only now introducing tests.
Doctors at the University of Florence in Italy analysed data from 30,065 athletes who had electrocardiogram (ECG) heart tests over a five-year period ending in 2006. Italy introduced mandatory heart check-ups 25 years ago.
The study found that after a first scan doctors identified 348 (1.2%) athletes with abnormal heart activity. A second scan, after exercise, revealed 1,459 (4.9%) had some form of heart abnormality.
Francesco Sofi, who led the study, said: "The use of this kind of screening could identify people who are at high or moderate risk of having a cardiac accident during sport," said Sofi.
The study follows a spate of sudden deaths among footballers, including the 35-year-old Motherwell midfielder Phil O'Donnell, who collapsed in December, and the 22-year-old Spanish international Antonio Puerta, who died last August.