Artifacts in portable electrocardiographic monitoring.

The development of portable ECG monitoring techniques has brought with it new insights into the electrical activity of the heart, and new problems in interpretation of artifacts. This article summarizes and classifies 15 different types of artifacts observed from dynamic electrocardiography. The artifacts appear partly as pseudo-arrhythmias mimicking supraventricular, ventricular, junctional, and dissociative rhythms. There are also non-arrhythmic artifacts which can be misleading in the interpretation of Q-waves, S-T-segments, and T-waves. Eight of the 15 artifacts have potentially serious consequences if not understood, and in 2 instances an artifact almost led to the unnecessary implantation of an artificial cardiac pacemaker.