RESUMO
Objectives: To plot and analyze ECG three-dimensional (3D) RR scatter plots in patients with various diseases in order to find the correlation between the graphic features and various diseases. Methods: According to ECG data provided by Physio Bank website, 3D RR scatter plots were constructed and analyzed by means of Matlab platform programming and clustering algorithm in following clinical settings: normal sinus rhythm,?arrhythmia, atrial fibrillation (AF), sudden cardiac death and chronic heart failure (CHF). Results: 3D RR scatter plots of normal sinus rhythm, arrhythmia, AF, sudden cardiac death and CHF were converged into several categories, all had the features of ultimate, stability and attraction. Significant differences on the number of clusters, clustering degrees and distribution ranges were observed among subjects with normal sinus rhythm, arrhythmia, AF, sudden cardiac death and CHF. Conclusions: 3D RR scatter plots had diversified distributions in different diseases, it can be divided into multiple categories with multi-distribution features. 3D RR scatter plots can clearly define the overlapping parts of 2D scatter diagram and are helpful to distinguish different diseases in a more accurate mode, future studies are warranted to explore the underlying clinical implications of the multiple parameters derived from the 3D RR scatter plots.