Heart diseases discovered by mass screening in the schools of Shimane Prefecture over a period of 5 years.

Mass screening by ECG for heart diseases in pupils and students was performed in Shimane Prefecture; all the children had primary screening and were under the supervision of a pediatric cardiologist in all phases, from primary to precise (tertiary) examination. The precise examination was performed with 2D echo, exercise ECG and/or cardiac catheterization when indicated, and an important feature of this mass screening was the ability to carry out an accurate follow-up in all the phases from primary to precise examination. The number of subjects in the primary screening from 1980 to 1984 was 50758 primary school pupils, 44216 junior high school students and 33480 senior high school students; organic heart diseases not under the supervision of the pediatric cardiologist at the time of mass screening were found in 22 primary school pupils (0.04% of participants in the primary screening), 14 junior high school students (0.03%) and 5 senior high school students (0.01%). Clinically significant arrhythmias without underlying organic heart diseases were discovered by mass screening in 8 primary school pupils (0.02%), 13 junior high school students (0.02%) and 16 senior high school students (0.05%).