A system and method for facilitating a cardiac rhythm disorder diagnosis with the aid of a digital computer is provided. A plurality of R-wave peaks are identified in a set of ECG data and a difference between recording times of successive pairs of the R-wave peaks are calculated as R-R intervals. A heart rate associated with each time difference is determined. An R-R interval plot of the ECG data is formed. The R-R intervals are plotted along an x-axis of the R-R interval plot and the heart rates associated with the R-R intervals are plotted along a y-axis of the R-R interval plot. A diagnostic composite plot is generated, including the R-R interval plot, a near field view of a portion of the ECG data, and an intermediate field view of a different portion of the ECG data for diagnosis of a cardiac event.