Abstract：Objective To explore the principle of superposition diagram and its application in the analysis of ambulatory electrocardiography (AECG). Methods We selected 4 typical AECG cases related to morphological information (sinus rhythm and ventricular rhythm, sinus rhythm and atrial rhythm, sinus rhythm and junctional rhythm, DDD pacing mode and VAT pacing mode of dualchamber pacemaker). The principle and advantages of superposition diagram were analyzed, and summarized in combination with Lorenz scattered plot, ECG waterfall diagram and reverse technique. Results Ventricular rhythm showed a wide QRS complex pattern, while sinus rhythm was manifested by a narrow QRS complex pattern; the above two rhythms could be separated rapidly by superposition diagram. The sinus rhythm showed upright Pwave, while atrial rhythm showed inverted Pwave; the above two rhythms could be quickly separated by superposition diagram. The sinus rhythm showed upright Pwave, while the junctional rhythm showed no Pwave; the above two rhythms could be separated quickly by superposition diagram. In the DDD pacing mode of dualchamber pacemaker, the double pulses of AP and VP could be observed, while the single pulse of VP appeared in the VAT pacing mode; the two kinds of pacing modes could be quickly separated by superposition diagram. Conclusion The superposition diagram has unique advantages in the analysis of AECGs with morphological information changes, and it is another efficient tool for rapid analysis of AECGs.
