The effects of exercise and smoking on the electrocardiograms and ballistocardiograms of normal subjects and patients with coronary artery disease

1. 1. The response of the electrocardiogram and ballistocardiogram to exercise and smoking in 200 subjects has been reported. 2. 2. The ballistocardiogram in 7.9 per cent of normal control subjects and in 31.4 per cent of patients with coronary artery disease deteriorated after exercise. 3. 3. The electrocardiographic response to exercise was positive by Master's criteria in 22.8 per cent of normal controls, and in 50 per cent of the subjects with angina pectoris or remote myocardial infarction. 4. 4. The diagnostic margin of differentiation between diseased persons and normal controls obtained by the “stress” of exercise was 4:1 by the ballistocardiograph and 2:1 by the electrocardiograph. 5. 5. The ballistocardiogram in 6.8 per cent of normal control subjects and in 58.6 per cent of patients with coronary artery disease deteriorated after smoking a cigarette. 6. 6. The diagnostic margin obtained with the cigarette test was 9:1. 7. 7. Administration of 0.5 mg. of nicotine base sublingually elicited ballistocardiographic alterations which were similar to those observed after smoking in 10 subjects.