RESUMO
BACKGROUND AND HYPOTHESIS: The aim of this study was to define the prevalence of previously undetected coronary heart disease among asymptomatic males, aged 30-65 years, by means of resting and exercise electrocardiography in conjunction with an analysis of conventional and exertional coronary risk factors. METHODS: Between January 1985 and December 1989 we examined 5,000 clinically asymptomatic subjects. A detailed case history was obtained for each individual, followed by a complete physical examination, comprehensive blood (including lipid) profile, lung function tests, chest x-ray, a resting 12-lead electrocardiogram (ECG), and a maximal treadmill exercise ECG. Whenever possible, on-line computerized respiratory analysis (Beckman Metabolic Measurement Cart) was carried out during the exercise tests. Conventional and exertional coronary heart disease risk factors were also recorded. RESULTS: A total of 162 persons (3.2%) showed abnormal S-T segment responses during the exercise or recovery period. Of these, 92 subjects underwent further investigations: coronary angiography (79), 201thallium scanning (13), 201thallium scanning followed by coronary angiography (7). Of the 86 patients who proceeded to coronary angiography, 19 (22%) had either normal coronary artery anatomy or only insignificant disease. Among the 67 (78%) of patients with significant angiographically demonstrable disease, 26 received coronary artery bypass grafting, 7 underwent coronary angioplasty, and the remainder continued on medical management. CONCLUSIONS: These results are discussed in relation to a variety of conventional and exertional coronary risk factors.