Hypothermia-induced J waves

A 36 years old woman with acquired immunodeficiency syndrome was admitted to the hospital for pulmonary Mycobacterium Avis Complex infection. Seventy-two hours after the admission she became hypothermic and bradycardic. The ECG showed sinus bradycardia, J waves in leads II, III, aVF, aVR, aVL, V5 and V6 along with QT prolongation and T wave abnormalities. After rewarming the J waves and repolarization abnormalities disappeared. The proposed cellular basis of hypothermia-induced J waves is the accentuation of the spike-and-dome morphology of the action potential of M and epicardial cells.