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

Figure 6 Equipment-related artifacts. A: Deceleration artifact (orange box) causing narrowing of the QRS complex and giving a false impression of a spurious atrial premature contraction (arrow) advancing the next QRS complex (note the further narrowing of the QRS complex due to paper deceleration) in an ongoing narrow complex tachycardia; B: Deceleration artifact (orange box) causing narrowing of the QRS complex (nearly a straight vertical line - arrows) (note the narrowing of the preceding and the next T waves due to paper deceleration); C: Acceleration artifacts cause stretching of the ST segment, resulting in a false impression of sinus slowing. Prolonged stretching may lead to false impressions of significant sinus pauses or atrioventricular blocks. Note that the initial paper deceleration caused narrowing of the QRS complex, followed by paper acceleration; D: Filtering error causing a sharp artifact after the QRS complex, resulting in a false impression of double-QRS (arrows); E: Similar error in filtering causing significant distortion of waveforms with a baseline shift, making the electrocardiogram incomprehensible.