ECG tutorial: Myocardial ischemia and infarction
- Jordan M Prutkin, MD, MHS, FHRS
Jordan M Prutkin, MD, MHS, FHRS
- Associate Professor of Medicine, Division of Cardiology, Electrophysiology Section
- University of Washington
The electrocardiogram (ECG) is an important test used in the clinical evaluation of patients with suspected or known myocardial ischemia or myocardial infarction (MI). In order to recognize abnormalities that suggest ischemia or infarction, it is important to understand the components of a normal ECG. (See "ECG tutorial: Basic principles of ECG analysis".)
In patients with myocardial ischemia or infarction, findings on the ECG are influenced by multiple factors, including the following:
●Duration – Hyperacute/acute versus evolving/chronic
●Size – Amount of myocardium affected
●Anatomic location – Anterior, lateral, or inferior-posterior
- Mirvis D, Goldberger AL. Electrocardiography. In: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 10th ed, Mann DL. (Ed), Elsevier/Saunders, Philadelphia 2014.
- Wagner GS, Macfarlane P, Wellens H, et al. AHA/ACCF/HRS recommendations for the standardization and interpretation of the electrocardiogram: part VI: acute ischemia/infarction: a scientific statement from the American Heart Association Electrocardiography and Arrhythmias Committee, Council on Clinical Cardiology; the American College of Cardiology Foundation; and the Heart Rhythm Society. Endorsed by the International Society for Computerized Electrocardiology. J Am Coll Cardiol 2009; 53:1003.
- Thygesen K, Alpert JS, Jaffe AS, et al. Third universal definition of myocardial infarction. Circulation 2012; 126:2020.
- Casas RE, Marriott HJ, Glancy DL. Value of leads V7-V9 in diagnosing posterior wall acute myocardial infarction and other causes of tall R waves in V1-V2. Am J Cardiol 1997; 80:508.
- ELECTROPHYSIOLOGIC BASIS OF ST-SEGMENT DEVIATION
- ACUTE MYOCARDIAL ISCHEMIA AND INFARCTION
- T wave changes
- ST-segment depression
- ST-segment elevation
- Location of ECG changes
- ST-elevation MI evolution
- Non-ST elevation MI
- Post-ischemic T wave inversions
- ST changes in the setting of conduction abnormalities
- PRIOR Q WAVE MYOCARDIAL INFARCTION
- Anterior wall MI
- Anterolateral wall MI
- Lateral wall MI
- Inferior wall MI
- Posterior wall MI