Abstract：ObjectiveTo explore the characteristics of atrial, ventricular and junctional escape rhythms in ECG waterfall diagram, and to lay a foundation for rapidly analyzing ambulatory electrocardiography of chronic arrhythmias such as sick sinus syndrome (SSS). MethodsA patient diagnosed with SSS complicated by the above three escape rhythms were selected. The characteristics of ECG waterfall diagram were further analyzed based on the routine view of the ECG scatter plots. Combined with the reversal technique of ECG waterfall diagram, we analyzed and summarized the characteristics of ECG waterfall diagrams of the three escape rhythms, and their correspondence with the corresponding ECGs. ResultsUnder the background of sinus block or sinus arrest, the frequencies of the three protective escape rhythms (atrial, ventricular and junctional escape rhythms) in the patient with SSS were close, competing with each other and alternating repeatedly. The characteristics revealed by the common analytical tools such as ECG scatter plot and RR interval histogram were not obvious, but the features of the ECG waterfall diagram of each rhythm were different which provided a shortcut to rapidly analyze this kind of cases. The R-peak band of normal sinus rhythm was horizontally centered and its width was 120 ms or less. The chromatogram represented the height of QRS complex. The P- and T-peak bands were in parallel, separately located at the upper and the bottom of R-peak band. The width and chromatography represented the duration and polarity of P- and T-waves, respectively. Rhythm transformation was indicated by the changes of the width or chromatography of the threepeakband ECG waterfall diagram of sinus rhythm. The ECG waterfall diagram characteristics of atrial escape rhythm were as follows: P-peak band was allochroic while R- and T-peak bands were normal. The ECG waterfall diagram characteristics of ventricular escape rhythm were as follows: P-peak band disappeared, R-peak band was widened and allochroic, and T-peak band changed its color. The ECG waterfall diagram characteristics of junctional escape rhythm were as follows: P-peak band disappeared while R- and T-peak bands were normal. ConclusionECG waterfall diagram could be used to quickly identify various kinds of escape rhythms in SSS patients, which makes up for the shortcomings of ECG scatter plot and RR interval histogram in ECG big data analysis.
