Delta Wave Overview
The Delta wave is a slurred upstroke in the QRS complex often associated with a short PR interval. It is most commonly associated with pre-excitation syndrome such as WPW.
The characteristic ECG findings in the Wolff-Parkinson-White syndrome are:
- Short PR interval (< 120ms)
- Broad QRS (> 100ms)
- A slurred upstroke to the QRS complex (the delta wave)
In 1930, Wolff, Parkinson, and White erroneously thought that the wide QRS complex was caused by a type of bundle-branch block. This was corrected in 1933 by Wolferth and Wood.
in 1944 Segers PM, Lequime J and Denolin proposed the symbol Δ to represent the triangle shape at the base of the upsloping QRS complex. They described the ‘… deformation of the PQ segment is the result of a supplementary electrical deflection that we propose to call Δ‘ . This became more commonly described as the ‘delta wave‘
ECG examples of Delta Waves
Negative delta waves (e.g. seen in lead aVR)
- Wolff-Parkinson-White syndrome
- Who’s Afraid Of The Big Bad Wolff?
- VT versus SVT with aberrancy
- Puzzling Paroxysmal Palpitations
- Hurst JW. Naming of the waves in the ECG, with a brief account of their genesis. Circulation. 1998 Nov 3;98(18):1937-42. [PMID 9799216]
- Wolferth CC, Wood FC. The mechanism of production of short P-R intervals and prolonged QRS complexes in patients with presumably undamaged hearts: hypothesis of an accessory pathway of auriculoventricular conduction (bundle of Kent). American Heart Journal. 1933; 8: 297-311.
- Segers PM, Lequime J, Denolin H. L’activation ventriculaire précoce de certains cœurs hyperexeitables. Étude de I’onde Δ de I’électrocardiogramme. Cardiologia. 1944; 8(3-4):113-167.
ECG Library Basics
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