Osborn Wave (J Wave) Overview
The Osborn wave (J wave) is a positive deflection at the J point (negative in aVR and V1). It is usually most prominent in the precordial leads
Eponymously associated with John Jay Osborn (1917-2014) following his 1953 ‘current of injury‘ description in hypothermic dogs
Note: The letter J on the ECG defines 2 totally different and unrelated events. The J point is a point in time marking the end of the QRS and the onset of the ST segment present on all ECG’s; the J wave is a much less common long slow deflection of uncertain origin originally described in relation to hypothermia.
- The ECG finding of a positive deflection at the J point (negative in aVR and V1) with a dome or hump configuration is most frequently termed a J wave or Osborn wave.
- No definitive physiological cause for the deflection despite numerous postulates.
- Broad differential diagnosis of prominent Osborn waves including hypothermia; benign early repolarization; hypercalcaemia and the Brugada syndrome.
- In the setting of hypothermia this phenomenon is most commonly referred to as an Osborn wave. 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
Osborn Wave Causes
Characteristically seen in hypothermia (typically T<30C), but they are not pathognomonic. Causes of non-hypothermic Osborn waves include:
- Normal variant and early repolarization
- Acute myocardial ischaemia [Maruyama et al]
- Hypercalcaemia [Otero et al]
- Takotsubo cardiomyopathy [Zorzi et al]
- Left ventricular hypertrophy due to hypertension [Patel et al]
- 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)
Osborn Wave ECG examples
- Subtle J waves in mild hypothermia [Temp: 32.5°C (90.5°F)]
- The height of the J wave is roughly proportional to the degree of hypothermia
- J waves in moderate hypothermia. [Temp: 30°C (86°F)]
- J waves in moderate hypothermia. [Temp: 28°C (82.4°F)]
- Marked J waves in severe hypothermia [Temp: 26°C (78.8°F)]
Eponymous History of the Osborn Wave
1922 – Kraus described a J-point deflection in hypercalcaemic conditions
1938 – Tomaszewski et al. provided the first description of hypothermic J wave in an accidentally frozen man. He described the J wave as a very slowly inscribed deflection between the QRS complex and the ST segment of the ECG, resembling a “domed T wave.”
1950 – Bigelow described ECG changes in hypothermic dogs as:
…characterized by a doubling of the QRS interval, and lengthening of the QT interval by three to four times. The T-wave is long and irregular, and usually inverted.
1953 – Osborn studied the effect of hypothermia on the respiratory and cardiac function in dogs. Experimentally-induced hypothermia caused the development of a distinct deflection at the J point on the ECG and resulted in ventricular fibrillation. He called this deflection the ‘current of injury’. [Osborn JJ. Am J Physiol. 1953 Dec;175(3):389-98]
Osborn considered acidaemia induced by hypothermia as a primary cause of the Osborn wave, because it disappeared if the arterial pH was normalized by hyperventilation during the same degree of cooling
1959 Emslie-Smith (British Heart Journal, …changes in the ECG in hypothermia.) ‘The characteristic deflection of hypothermia has sometimes been named after Osborm who discussed it in 1953.’
1961 Duguid (The Lancet, Accidental hypothermia) ‘The electrocardiogram may show the distinctive ‘J’ or ‘Osborn’ wave’
1996 – Yan and Antzelevitch provided first direct evidence in support of the hypothesis that:
‘heterogeneous distribution of a transient outward current-mediated spike-and-dome morphology of the action potential across the ventricular wall underlies the manifestation of the electrocardiographic J wave. The presence of a prominent action potential notch in epicardium but not endocardium is shown to provide a voltage gradient that manifests as a J (Osborn) wave or elevated J-point in the ECG‘
Many alternate names have been assigned in medical literature including ‘camel hump sign of Osborne‘; ‘hypothermic hump‘; ‘late delta wave’; ‘hathook junction’; ‘J wave’; ‘H wave’ and ‘K wave’
- Kraus F. Ueber die Wirkung des Kalziums auf den Kreislauf. Deutsche medizinische Wochenschrift. 1920; 46: 201–203.
- Kraus F, Zondek SG. Uber die Durchtrankungsspannung. Klinische Wochenschrift. 1922; 36: 1778-1779.
- Tomaszewski W. Changements electrocardiographiques observes chez un homme mort de froid. Archives des Maladies du Coeur et des Vaisseaux. 1938; 31: 525-528
- Bigelow WG, Lindsay WK, Greenwood WF. Hypothermia; its possible role in cardiac surgery: an investigation of factors governing survival in dogs at low body temperatures. Ann Surg. 1950 Nov;132(5):849-66.
- Osborn JJ. Experimental hypothermia; respiratory and blood pH changes in relation to cardiac function. Am J Physiol. 1953 Dec;175(3):389-98.
- Emslie-Smith D, Sladden GE, Stirling GR. The significance of changes in the electrocardiogram in hypothermia. Br Heart J. 1959 Jul;21(3):343-51.
- Gussak I, Bjerregaard P, Egan TM, Chaitman BR. ECG phenomenon called the J wave. History, pathophysiology, and clinical significance. J Electrocardiol. 1995 Jan;28(1):49-58.
- Yan GX, Antzelevitch C. Cellular basis for the electrocardiographic J wave. Circulation. 1996 Jan 15;93(2):372-9.
- Hurst JW. Naming of the waves in the ECG, with a brief account of their genesis. Circulation. 1998 Nov 3;98(18):1937-42
- Maruyama M, Kobayashi Y, Kodani E, Hirayama Y, Atarashi H, Katoh T, Takano T. Osborn waves: history and significance. Indian Pacing Electrophysiol J. 2004 Jan 1;4(1):33-9
- Shinde R, Shinde S, Makhale C, Grant P, Sathe S, Durairaj M, Lokhandwala Y, Di Diego J, Antzelevitch C. Occurrence of “J waves” in 12-lead ECG as a marker of acute ischemia and their cellular basis. Pacing Clin Electrophysiol. 2007 Jun;30(6):817-9.
- Haïssaguerre M, et al. Sudden cardiac arrest associated with early repolarization. N Engl J Med. 2008 May 8;358(19):2016-23.
- Otero J, Lenihan DJ. The “normothermic” Osborn wave induced by severe hypercalcemia. Tex Heart Inst J. 2000;27(3):316-7.
- Omar HR. The Osborn wave: what have we learned? Herz. 2016 Feb;41(1):48-56.
- Cadogan M. History of the Electrocardiogram. LITFL
LITFL Further Reading
- ECG Library Basics – Waves, Intervals, Segments and Clinical Interpretation
- ECG A to Z by diagnosis – ECG interpretation in clinical context
- ECG Exigency and Cardiovascular Curveball – ECG Clinical Cases
- 100 ECG Quiz – Self-assessment tool for examination practice
- ECG Reference SITES and BOOKS – the best of the rest
- Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography
- Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric
- Wagner GS. Marriott’s Practical Electrocardiography 12e
- Chan TC. ECG in Emergency Medicine and Acute Care
- Rawshani A. Clinical ECG Interpretation
- Mattu A. ECG’s for the Emergency Physician
- Hampton JR. The ECG In Practice, 6e