The pacing point wanders within the heart. This is called a wandering rhythm. A wandering rhythm is one in which the location of the pacing point is not fixed, but is constantly changing. It can travel back and forth to different parts of the sinus node, or to different parts of the atrioventricular node, or between the sinus node, atria, and atrioventricular node. So, which arrhythmia should be distinguished from the atrial wandering rhythm in patients? The following is a brief description: The following arrhythmias should be differentiated: 1. Atrial prophase contraction: The P-wave pattern should be exactly the same in sinus arrhythmia, or gradually change mildly: while the P′ wave of atrial prophase contraction is completely different from the sinus P-wave pattern. The P-P interval is not exactly the same in sinus rhythm, while the atrial pre-systolic rhythm changes suddenly and excitedly in advance, followed by an incomplete compensatory interval. 2. Second degree type I sinus block: The change of P-P interval in sinus arrhythmia is gradual shortening followed by gradual lengthening, while the gradual shortening of P-P interval in second degree type I sinus block is followed by a long interval, and after this interval the P-P interval is gradually shortened again, independent of the respiratory cycle. The change of sinus arrhythmia P-P interval is related to the respiratory cycle, and the sinus arrhythmia disappears when the respiration is temporarily stopped. 3.Irregular second degree sinus block: the P-P interval in sinus arrhythmia is gradually shortened and prolonged. The change is closely related to the respiratory cycle; while the P-P interval is suddenly prolonged in second degree sinus block, which is not related to the respiratory cycle.