This is the ECG of a patient with severe hypothermia-a body temperature of 84 degrees Fahrenheit (29 degrees Centigrade). The asterixes show a hump where the QRS complex joins the ST segment. This is called an Osborne wave or J-wave. The tracing also shows a slow heart rate of 43 beats per minute-also characteristic of hypothermia. The underlying rhythm here arises from the atrioventricular node-there are no P waves-and thus constitutes a junctional rhythm.
Other ECG findings of hypothermia include prolongaton of the PR interval, QRS duration and QT interval. Aside from junctional rhythms and sinus bradycardia one can also see atrial flutter or fibrillation as well as premature venricular beats and fatal sustained ventricular arrhythmias.