A left ventricular aneurysm can be diagnosed on ECG when there is persistent ST segment elevation occurring 6 weeks after a known transmural myocardial infarction (usually an anterior MI). Without knowing the past medical history, the ECG changes of an aneurysm may mimic an acute anterior MI.
With an anterior or apical aneurysm, the persistent ST elevation is in lead V1 and V2 with associated Q waves indicating the old anterior MI. In an inferior aneurysm it would be in lead II, III and aVF, although this is less common. The only way to be sure that the ECG changes present are from an LV aneurysm (not ST elevation from an acute MI) is to have the patient’s history of a prior MI and cardiac imaging to document the presence of an aneurysm. The shape of the ST elevation is also relatively unique and has been described as “coving” as seen below:
- Chou's Electrocardiography in Clinical Practice: Adult and Pediatric, Sixth Edition, Saunders, Philadelphia, 2008.
- Surawicz B et al. ACC/AHA recommendations for the standardization and interpretation of the electrocardiogram. Circulation. 2009;119:e235-240.