What is the appearance of an artificial pacemaker on an EKG?

An artificial pacemaker typically appears on an EKG as a straight, hard vertical line or spike. This visual characteristic occurs because the pacemaker generates electrical impulses that stimulate the heart to contract. When these impulses are transmitted through the myocardium, they create a rapid and distinct spike on the EKG tracing, seen as a sharp vertical line. This spike marks the moment the pacemaker delivers its impulse, distinguishing it from the typical waveform seen with natural heart activity, which consists of rounded P waves, QRS complexes, and T waves.

The pacemaker spike is often followed by a QRST complex (if it is functioning properly) or can stand alone if the pacemaker is not effectively capturing a myocardial contraction. The presence of these spikes can provide critical information regarding the functioning of the pacing system—such as appropriate lead placement and capture of the heart muscle.

Other choices do not accurately describe the pacemaker's appearance. A series of waves would suggest a normal electrical rhythm from the heart without intervention, while a continuous line does not reflect the discrete nature of electrical impulses generated by a pacemaker. A significantly irregular pattern could indicate a problem with heart rhythm, which is unrelated to the regular, consistent pacing provided by an artificial pacemaker.