Normokalemic Littmann sign due to STEMI

Area of Science:

• Cardiology
• Internal Medicine
• Medical Diagnostics

Background:

• The Littmann sign, characterized by double heart rate counting on electrocardiograms (ECGs), typically suggests severe hyperkalemia.
• Misinterpretation of ECG findings can lead to diagnostic delays and inappropriate management.

Purpose of the Study:

• To report a rare case of false double heart rate counting in ST-elevation myocardial infarction (STEMI).
• To highlight that peaked T-waves in STEMI can mimic the Littmann sign, potentially caused by computer error.

Main Methods:

• Case report presentation.
• Review of electrocardiogram (ECG) findings in a patient with anterior STEMI.
• Analysis of potential causes for artifactual ECG abnormalities.

Main Results:

• A patient with anterior STEMI exhibited ECG findings suggestive of double heart rate counting.
• This artifact was attributed to computer error and peaked T-waves, not hyperkalemia.
• The Littmann sign was mimicked, underscoring the importance of careful ECG interpretation.

Conclusions:

• The Littmann sign is not exclusive to hyperkalemia and can be observed in acute STEMI.
• Peaked T-waves in STEMI can lead to computer-generated false double heart rate counts.
• Clinicians must consider STEMI in the differential diagnosis of apparent Littmann sign to avoid diagnostic errors.