Ninety-six per cent of the original subjects were traced after a period of 10 to 12 years; 202 were dead, and data obtained on re-examination were complete for 639. Except in one case of myocardial infarction, subjects with "borderline" or frank electrocardiographic abnormalities showed no symptoms of the development of heart disease. It is argued that the borderline abnormalities, considered as a group, must have little pathologic significance; otherwise, out of the relatively large number of subjects in this group, some would have exhibited symptoms. Although heart disease did not develop in any of the subjects with frank electrocardiographic abnormalities, such as bundle-branch block, the same argument does not hold with equal force because of the small number of cases in that group.