[Pifalls in the interpretation of pacemaker ECGs]

The analysis of the pacemaker ECG is usually regarded as difficult and may generate rather mediocre interpretations. It is a common opinion that a pacemaker ECG can only be analyzed if the type of pacemaker (single-, dual-, triple-chamber, manufacturer, model) and its programming are known. The following pitfalls illustrate how to achieve a clinically meaningful ECG interpretation in daily practice, even if these details are not known. A systematic approach to ECG interpretation is particularly crucial in this context: Basic rhythm (P waves, intrinsic or paced rhythm), paced QRS complex (axis, width, bundle branch block morphology), signs of pacemaker malfunction (under‑/oversensing, loss of capture), arrhythmia to which the pacemaker reacts, or activity of any pacemaker algorithm. Many small details should not be overlooked and many questions can be answered if a few principles are applied. Understanding of the pacemaker ECG can improve the life of a device patient at the touch of a button.