Thomas W. Clark

A comparison of electrocardiographic changes observed during the "anoxemia test" on normal persons and on patients with coronary sclerosis

Abstract 1. 1. In 157 cases of coronary sclerosis, the anoxemia test was electrocardiographically positive in 49 per cent, and furnished presumptive evidence of coronary insufficiency, by the occurrence of pain, in another 20 per cent. It was thus helpful in the recognition of a diminished coronary reserve in 69 per cent. 2. 2. The RS-T deviation in each individual lead, as well as the total RS-T deviation in the four leads which were employed, was greater in the 157 patients with coronary sclerosis than in 136 normal persons. 3. 3. The amount of total RS-T deviation usually increased in linear fashion in relation to the duration of the period of anoxemia. Occasionally the degree of deviation rose to a peak level and then decreased, suggesting that compensatory mechanisms operated to bring about a favorable adjustment in coronary blood flow. 4. 4. Comparison of the results on different patients with coronary sclerosis showed no direct relationship between the duration of the test and the amount of total RS-T deviation; patients who breathed the lowoxygen mixture for twenty minutes did not tend to show greater RS-T deviation than those whose tests were terminated earlier because of pain. 5. 5. The incidence of significant T-wave change increased with the degree of total RS-T deviation. 6. 6. The combination of partial T-wave reversal and RS-T deviation of 1 mm. or more in Lead IVF, as the sole criterion of a positive test, was observed in less than 2 per cent of the cases of coronary sclerosis and was found with equal frequency in normal persons. Its use as a sign of a positive reaction has, therefore, been discontinued.

Mortality among males in periodic-health-examination programs.

Abstract Between 1950 and 1964, 20,648 males, almost all white and mostly in managerial positions and upper socioeconomic levels, were examined in employer-sponsored periodic-health-examination programs at eight co-operating clinics. Over this period, involving more than 138,000 man-years of exposure to the risk of death, 1018 of the men died. In relation to the experience of reasonably comparable groups, the ratio of actual to expected deaths in the total population examined varied from 0.60 to 0.997. For men examined two or more times, the ratio varied from 0.48 to 0.81 for the total period of exposure to the risk of death, and from 0.57 to 0.92 for the period of exposure after the second examination. The data presented are compatible with a favorable influence of periodic health examinations on mortality experience, but do not allow conclusions of such an effect. They do encourage well controlled prospective studies of the question.

THE PERIODIC HEALTH EXAMINATION: EVALUATION OF ROUTINE TESTS AND PROCEDURES

Excerpt The periodic health examination has been accepted as an effective means of detecting disease in asymptomatic people.1-4The type of examination in different clinics is generally similar and ...

Clinical and Biological Observations on Working Men

Data are presented from the first examination of 14,110 men examined in regular periodic health examination programs. The wide range for 13 commonly used biological measurements suggests that normal ranges may be wider than commonly supposed. The proportion of the population showing evidence of 13 selected diseases increased with age but the order of frequency within age groups was notably different. The mean value of some biological measurements increased with age while others decreased. Certain diseases were associated with changes in measurements that exceeded those associated with age, and mean values among persons with a given diagnosis often differed significantly from those in persons without the diagnosis. This large population provides a resource for the study of chronic disease.