Effect of cooling the anterior chest wall on the T wave of the electrocardiogram

Abstract

Electrocardiographic records were obtained in sixteen subjects, with apparently normal hearts, before and after cooling the precordial region of the chest wall by placing an ice bag on it for five to six minutes. Cooling the chest wall gave rise to depression of the T wave in Leads V 1 to V 4. This was associated, in most cases, with increase in positivity of the T wave in Leads aV F and V 8. The T-wave changes resulting from cooling the chest wall were, in the main, of opposite pattern to those resulting from drinking iced water. More marked T-wave changes were obtained from subjects with a thinner chest wall and lower pelidisi as compared with subjects with a thicker chest wall and higher pelidisi. The T-wave changes lasted for about twenty-five minutes. The ventricular gradient shifted, on the average, slightly (about 2°) to the left. The T-wave changes were not related to the increase in blood pressure which occurred in most, but not all, of the subjects as a result of cooling the chest wall. The Q-T interval was not markedly altered. Cooling the chest wall on the right side, away from the heart region, or cooling the abdominal wall, did not give rise to electrocardiographic changes, although it gave rise to an increase in blood pressure.