A rare rhythm in a pulseless patient: ECG challenge

Area of Science:

• Cardiology
• Medical Instrumentation
• Emergency Medicine

Background:

• Automated external defibrillators (AEDs) and patient monitors commonly use signal processing to interpret cardiac rhythms.
• Artifacts from these systems can potentially lead to misinterpretation of critical arrhythmias during resuscitation efforts.
• Wide Complex Tachycardia (WCT) is a potentially life-threatening arrhythmia requiring specific management protocols.

Purpose of the Study:

• To report a case where an automated monitor artifact mimicked Wide Complex Tachycardia (WCT).
• To highlight the potential for misdiagnosis during Advanced Cardiac Life Support (ACLS) due to signal processing errors.
• To emphasize the importance of critical evaluation of monitor rhythms in challenging clinical scenarios.

Main Methods:

• Case report of a patient experiencing cardiac arrest.
• Initial rhythm interpretation by a monitor suggested Wide Complex Tachycardia (WCT).
• Acquisition of a 12-lead electrocardiogram (ECG) for definitive rhythm diagnosis.

Main Results:

• The monitor rhythm was determined to be a pseudo-tachycardia artifact caused by auto-gain amplification.
• The definitive 12-lead ECG revealed ventricular standstill, a different clinical entity.
• This artifact mimicked a life-threatening arrhythmia, potentially altering initial management.

Conclusions:

• Automated signal processing in cardiac monitors can generate artifacts that mimic critical arrhythmias like WCT.
• Clinicians must remain vigilant for such artifacts, especially during Advanced Cardiac Life Support (ACLS).
• A 12-lead ECG remains crucial for accurate diagnosis when monitor interpretation is uncertain or potentially artifactual.