Mechanical Fall

A 72-year-old woman presents to the ED for a wrist injury sustained after a fall. She states she fell because she lost her balance and did not feel weak or light-headed prior to the fall. She also states that she did feel “woozy” after she fell, but currently she denies any symptoms other than right wrist pain. She denies any chest pain, trouble breathing, or other complaints.

Her examination is unremarkable except for a systolic murmur and a mild deformity and tenderness to her right wrist. Her skin is intact, her compartments soft, and distal neurovascular status is within normal limits. You administer 4 mg of morphine IV for pain and initiate a near-syncope work up because of her age just in case something else is going on.

Laboratory results, including a CBC, metabolic panel, and cardiac enzymes are normal except for a white blood cell count of 11.3 x 10³/µL. A wrist X-ray shows a distal radius fracture, which you splint and sling.

Her ECG is shown below.

What is your ECG read?

Answer and discussion on next page>>

Answer: Lateral ST-elevation MI

Note the ST-elevation in V4-V6, which was markedly changed from the baseline ECG. Troponins became positive at 8 hours.

Discussion

In addition to clinical skills, careful ECG interpretation is critical to avoid errors in management of patients with acute coronary syndrome (ACS). ST elevation can be subtle early during a STEMI, especially if changes are in the inferior or lateral leads. T-waves tend to be smaller and benign early repolarization less pronounced in the lateral leads. When the lateral leads look like anterior leads, STEMI should always be considered, especially if there is more ST elevation or larger T-waves in the lateral leads than is present in the anterior leads, as in this case.

It is also essential to keep in mind that an ECG can be normal during an ACS, especially early on. Comparison with an old ECG and serial ECGs can be critical. Remember, the most recent ECG may have been recorded during an acute MI, so just because the current one looks the same does not rule out ACS. See page shot below for more information on EKG changes in ACS.

Page capture on ECG findings in ISCHEMIA from the QUICK ESSENTIALS Emergency Medicine 1-Minute Consult pocketbook