Here is the update to 81 year old male CC: “Cold and shaky”.
Let’s take another look at the 12-lead ECG.
At first glance the ST-elevation in the inferior and low lateral leads isn’t that impressive, at least when compared to some of the other cases we’ve seen. However, this is an impressive amount of ST-elevation when compared to the small size of the QRS complexes! This is known as the rule of proportionality and it’s critically important when it comes to STEMI recognition!
Perhaps more impressive is the ST-depression in the right precordial leads (V1-V3). These are reciprocal changes to posterior extension of this acute inferior STEMI. If this was the only abnormality on this ECG I would still call it STEMI! If you want to get really good at identifying acute isolated posterior STEMI, pay attention to the right precordial leads whenever you have an acute inferior STEMI. These changes will often be present.
Of course, you already knew that the ST-elevation in the inferior leads indicated STEMI. Why? Because of the downsloping ST-segment in lead aVL! This is the “go to” lead to “rule-in” acute inferior STEMI! It is so sensitive and specific that absence of this finding should make you question the ECG diagnosis of acute inferior STEMI.
So what happened?
The patient was sent to the cardiac cath lab where angiography revealed 100% occlusion of the right coronary artery (RCA). A stent was successfully placed and the patient is doing well.
Diagnosis: Acute Inferior ST-Elevation Myocardial Infarction