Osborn J waves

71 year old intoxicated patient found lying outside in the cold. Core temp 83 degrees.

The Osborn wave (J wave) is a positive deflection seen at the J point in precordial and true limb leads. It is most commonly associated with hypothermia. These changes will appear as a reciprocal, negative deflection in aVR and V1.

Osborn Wave Causes

Characteristically seen in hypothermia (typically T < 30C), but they are not pathognomic. Causes of non-hypothermic Osborn waves include:

• Hypercalcaemia [Otero et al]

• Acute myocardial ischaemia [Maruyama et al]

• Takotsubo cardiomyopathy [Zorzi et al]

• Left ventricular hypertrophy due to hypertension [Patel et al]

• Normal variant and early repolarization

• Neurological insults such as intracranial hypertension, severe head injury and subarachnoid haemorrhage

• Severe myocarditis

• Brugada syndrome [Bjerregaard et al]

• Le syndrome d’Haïssaguerre (idiopathic VF)

No definitive physiological cause for the deflection has been described, despite numerous postulates.

Compared to other hypothermia-induced ECG abnormalities (e.g. sinus bradycardia; supraventricular arrhythmias, QT prolongation and AV block), the Osborn wave is thought to be the most specific.