Smith used the ratio of T wave amplitudes to QRS amplitudes in anterior ECG leads to distinguish an anterior myocardial infarction from a left ventricular aneurysm. This can help to decide if the patient has a true ischemic event or a "pseudoinfarct." The author is from the University of Minnesota in Minneapolis.
Parameters:
(1) sum of the T wave amplitudes in leads V1 to V4
(2) sum of the QRS wave amplitudes in leads V1 to V4
ratio of the T to QRS amplitudes =
= SUM(T wave amplitudes) / SUM(Q wave amplitudes)
Interpretation:
• A ratio > 0.22 indicates that the patient probably has an acute myocardial infarction.
• A ratio <= 0.22 favors a left ventricular aneurysm.
Performance:
• 35 of 37 AMI patients (95%) were correctly classified. The 2 false negatives had delayed presentations (6 and 12 hours).
• 20 of 22 left ventricular aneurysm patients (91%) were correctly identified.
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