Exercise testing with myocardial scintigraphy in asymptomatic diabetic males
Abenavoli, T.; Rubler, S.; Fisher, V.J.; Axelrod, H.I.; Zuckerman, K.P.
Circulation 63(1): 54-64
1981
ISSN/ISBN: 0009-7322 PMID: 7438408 Document Number: 172556
Diabetic males, 16, 32-60 yr old (mean 48.7 .+-. 8.9 yr), without clinical or ECG evidence of heart disease and 12 normal volunteers, mean age 48.9 .+-. 8.8 yr, participated in maximal exercise testing combined with 201T myocardial scintigraphy. A motorized treadmill was used with the Bruce protocol. A standard 12-lead ECG and systolic blood pressures were recorded every minute during exercise and for at least 8 min in the postexercise period. Echocardiograms were obtained at rest for chamber dimensions and myocardial function. At maximal stress the heart rate attained by the normal controls was higher (174.5 .+-. 17.4 beats/min) than that of the diabetic males (163.1 .+-. 9.9 beats/min) (P < 0.05). Although the maximal systolic blood pressure for both groups was comparable (215.9 .+-. 32.5 mm Hg for the diabetics vs. 209.6 .+-. 21.6 mm Hg for the normal controls), maximal systolic blood pressures > 210 mm Hg occurred in 3 of 12 normal subjects (25%) but was noted in 9 of 16 diabetics (56.2%). The duration of exercise was longer in controls (663.0 .+-. 92.1 s) than in the diabetics (519.0 .+-. 127.2 s) (P < 0.005). The estimated maximal O2 consumption was increased in controls vs. diabetics (P < 0.005). Functional aerobic impairment was greater in the diabetics (10.4 .+-. 19.1%) compared with normal controls (-7.8 .+-. 9.0%). Significant ST-segment changes were present in 2 diabetics and 1 control subject. Of the 12 diabetic subjects who underwent exercise testing with 201T, 5 (41.7%) had abnormal perfusion during stress or with stress and rest. Such abnormalities were present once in the 11 perfusion studies in healthy subjects. Echocardiographic findings were similar in both groups. The percent of myocardial fractional shortening was smaller in diabetics than in controls (P < 0.05). Of the 12 subjects who underwent myocardial scintigraphy, an abnormal exercise ECG or a myocardial perfusion defect appeared in 7 (58.3%) of the diabetics without overt cardiac disease and in only 1 normal subject. Asymptomatic subjects in this high-risk category of middle-aged diabetic males should be under close and repeated surveillance. [Coronary artery disease is the leading cause of death in diabetics.].