Electrocardiographic artifacts in clinical practice: A logical approach to recognition and prevention

Abstract

Electrocardiographic (ECG) artifacts are anomalous signals unrelated to cardiac electrical activity that interfere with our interpretation and management. They can mimic serious arrhythmias or ischemic changes and often lead to unnecessary interventions. Understanding why such artifacts occur requires a grasp of how ECG signals are recorded, from tiny millivolt-level cardiac signals traveling from the heart through skin electrodes, cables, amplifiers, filters, and finally the display on the monitors or ECG strip. At each step, artifacts may enter, whether from patient movement, tremor, electrode-skin interface problems, broken leads, environmental interference, or implanted devices. Although filters and digital processing aim to reduce noise, artifacts may still occur due to the significant overlap of the noise frequencies with those of the true cardiac signals, or they can arise from non-electrical causes. Recognition of these artifacts requires some logic: Correlating the ECG with patient status, assessing physiological plausibility, checking lead distribution, and confirming with ancillary signals. This review summarizes the physics of ECG recording in simple terms, classifies common artifacts and outlines practical bedside clues and preventive strategies. The goal is to provide a clear, clinically oriented framework so that artifacts are recognized not as rare technical nuisances but as everyday challenges that can be safely navigated through reasoning and awareness.

Keywords: Electrocardiographic; Electrocardiogram; Artifacts; Pulse tapping; Square wave; Electromagnetic interference; Orphan

Core Tip: Electrocardiographic artifacts are non-cardiac signals that corrupt monitoring, often mimicking serious arrhythmias or ischemia and leading to unnecessary interventions. They are introduced at various points in the recording chain - from patient movement and electrode issues to environmental interference - due to the tiny cardiac signal and frequency overlap with noise. Recognizing these artifacts is vital; it requires clinical correlation, checking physiological plausibility, and assessing lead distribution to avoid misdiagnosis and safely manage the patient. This review summarizes the physics of electrocardiographic recording in simple terms, classifies common artifacts and outlines practical bedside clues and preventive strategies.