By Ken Grauer, MD

Professor Emeritus in Family Medicine, College of Medicine, University of Florida

Dr. Grauer reports no financial relationships relevant to this field of study.

The ECG in the figure below was obtained from a 30-year-old man who was admitted to the hospital to “rule out myocardial infarction.” His symptoms of chest discomfort were thought to be atypical and unlikely to be due to a cardiac etiology. His initial ECG (not shown) was interpreted as normal. Evaluation, including serial troponins and stress testing, were deemed normal. Before sending the patient home, the ECG in the figure below was obtained.

Although the initial ECG on this patient was reported as normal, this predischarge tracing most certainly is not normal. The patient should not be discharged until further evaluation.

The rhythm in the figure is fairly slow and slightly irregular. Atrial activity is uncertain. Upright P waves are not seen in lead II, so the mechanism of the rhythm is not sinus. The QRS complex is narrow, and the rhythm is slightly irregular. It is hard to determine if ectopic atrial P waves are intermittently present, or if this is a minimally irregular form of atrial fibrillation. But what can be said is the rhythm is supraventricular; therefore, assessment of ST-T wave morphology for potential ischemic change is valid.

The most remarkable ST-T wave abnormalities are seen in the limb leads. There is ST elevation with an upward concavity in leads I and aVL. The most concerning finding is mirror-image opposite ST-T wave depression in lead III. This looks acute. The other two inferior leads (leads II and aVF) also show ST depression. The ST-T wave in lead V2 looks disproportionately tall and potentially hyperacute, given the reduced QRS amplitude in this lead.

We cannot comment on whether the initial ECG was truly normal since we were not shown this initial tracing. What can be said is that regardless of the negative work-up on this patient, the ECG in the figure shows alarming ST-T wave changes in the limb leads. Based on this ECG, the cardiologist decided to perform cardiac catheterization before discharge. Severe narrowing of the left circumflex artery was found, which was stented.

For more information about and further discussion on this case, please visit: http://bit.ly/2tShCXJ.

ECG Review