Latent coronary heart disease was suspected in 115 of 2014 apparently healthy middle-aged men after a baseline cardiovascular survey. One hundred five of these men underwent angiography and 36 were found to have normal coronary arteries (group 1). A 7 year follow-up survey revealed that: (1) three had died of sudden cardiac death, (2) four had received a diagnosis of cardiomyopathy, (3) one had developed aortic dilatation/aortic regurgitation since the baseline survey, (4) they all had a significantly more rapid decline in their physical performance and maximal heart rate levels from the time of the baseline survey to follow-up than did randomly selected normal controls (group 2), and (5) thallium study results were normal in both groups (27 and 26 patients), but technetium ventriculography revealed a subnormal increase in ejection fraction during exercise (less than 5% units) in 14 of 27 group 1 subjects and in 4 of 26 group 2 subjects. Thus, incipient heart disease may be present in subjects in whom coronary angiographic examination has removed a previous suspicion of coronary heart disease.