Thermographic Patterns of Angina Pectoris

Liquid crystals, encapsulated onto black Mylar tapes, were used as cutaneous temperature sensors in 50 male patients, who had thermographic examinations while they were being exercised on the treadmill, in an attempt to induce angina pectoris. Twenty-eight of the group remained free of pain and the exercise thoracic thermogram was essentially unchanged from the control or resting state. Twenty-two patients developed angina pectoris during exercise, of whom 21 had associated ST depression in the electrocardiogram, and 17 thermographic abnormalities. When the pain was unilateral (nine patients), skin coolness was invariable and was within the distribution of the pain. When the pain was central (13 patients), skin coolness was present in some of the patients (eight of 13) and was not always within the area of pain. When present, the skin coolness was transient and settled within minutes of relief of pain.