Woman with “Dull, Achy” Back Pain and Shortness of Breath
ANSWER
This ECG demonstrates normal sinus rhythm, right-axis deviation, evidence of a lateral MI, and inferolateral ST- and T-wave abnormalities.
Right-axis deviation is indicated by an R-wave axis between 90° and 180° and QS or QR complexes in lead I and/or aVL. While the most common cause of a right-axis deviation is right ventricular hypertrophy, it is also evident in a lateral MI. Evidence for the latter includes the presence of significant Q waves in leads I and aVL. Finally, inferolateral ST- and T-wave changes are evidenced by inverted T waves in leads II, III, aVF, and precordial leads V4 to V6.
ECG evidence of a lateral MI not present on a previous scan (eight months ago), in the presence of a normal troponin level, suggests a recent MI.