Practice ECGs

When you look at this ECG, you are not immediately bowled over by any obvious abnormalities. Closer inspection, however, leads you to the AMI. Let's start off by looking at the limb leads. We see ST depression in leads I and aVL. Remember, downward sloping ST segments in aVL are the first sign of an inferior AMI, a reciprocal change. Could this be such a case? Yes, when we look at II, III, and aVF, we see ST elevations in those leads. ST elevations and reciprocal ST depressions always indicate an AMI. This is definitely an IWMI.

For more advanced readers, whenever we see an IWMI we need to consider its three buddies, the three other regions of the heart that are associated with IWMIs: the right ventricular MI, the lateral MI, and the posterior MI. Do we have any evidence of an RV infarct? Yes, the ST segments in III are taller than those in II. Get right-sided leads to verify your suspicions. Do we see evidence of a lateral extension of the AMI? No. Is there evidence of posterior wall involvement? Yes. Note the ST segment depressions in V₁to V₃ with flipped T waves (carousel ponies without a dominant R wave). Also note that the ST segment depression in V₂ is more than half the ST segment elevation in aVF. This is consistent with involvement of the posterior wall in the AMI. Posterior leads would be helpful in verifying your diagnosis. To summarize, this patient has an infero-RV-posterior AMI. This puts a large amount of myocardium at risk, and the patient should be treated aggressively to reperfuse the areas involved.

« Back to All