- Myocardial inflammation in the absence of ischaemia.
- Often associated with pericarditis , termed myopericarditis.
- Usually a benign disease without serious long-term complications.
- In the acute setting can cause arrhythmias, cardiac failure, cardiogenic shock and death.
- May result in delayed dilated cardiomyopathy.
Causes of Myocarditis
- Viral – including coxsackie B virus, HIV, influenza A, HSV, adenovirus.
- Bacteria – including mycoplasma, rickettsia, leptospira.
- Immune mediated – including sarcoidosis, scleroderma, SLE, Kawasaki’s disease.
- Drugs / toxins – including clozapine, amphetamines.
ECG in Myocarditis
ECG changes can be variable and include:
- Sinus tachycardia.
- QRS / QT prolongation.
- Diffuse T wave inversion.
- Ventricular arrhythmias.
- AV conduction defects.
- With inflammation of the adjacent pericardium, ECG features of pericarditis can also been seen (= myopericarditis).
NB. The most common abnormality seen in myocarditis is sinus tachycardia with non-specific ST segment and T wave changes.
- Sinus tachycardia with non-specific ST segment changes
- Widespread concave ST elevation (pericarditic changes) in a child with viral myocarditis.
- Wiesbauer F, Kühn P. ECG Yellow Belt online course: Become an ECG expert. Medmastery
- Wiesbauer F, Kühn P. ECG Blue Belt online course: Learn to diagnose any rhythm problem. Medmastery
- Rawshani A. Clinical ECG Interpretation ECG Waves
- Smith SW. Dr Smith’s ECG blog.
- Mattu A, Tabas JA, Brady WJ. Electrocardiography in Emergency, Acute, and Critical Care. 2e, 2019
- Brady WJ, Lipinski MJ et al. Electrocardiogram in Clinical Medicine. 1e, 2020
- Straus DG, Schocken DD. Marriott’s Practical Electrocardiography 13e, 2021
- Hampton J. The ECG Made Practical 7e, 2019
- Grauer K. ECG Pocket Brain (Expanded) 6e, 2014
- Brady WJ, Truwit JD. Critical Decisions in Emergency and Acute Care Electrocardiography 1e, 2009
- Surawicz B, Knilans T. Chou’s Electrocardiography in Clinical Practice: Adult and Pediatric 6e, 2008
- Mattu A, Brady W. ECG’s for the Emergency Physician Part I 1e, 2003 and Part II
- Chan TC. ECG in Emergency Medicine and Acute Care 1e, 2004
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