When using a caliper for R-R interval measurements, which points are compared?

When measuring the R-R interval using a caliper, the proper points to compare are the R waves of successive QRS complexes. The R wave is the peak of the QRS complex and is important because it represents ventricular depolarization, which is a critical aspect of the cardiac cycle. By measuring the distance between the R waves of two consecutive heartbeats, you can accurately determine the R-R interval, which is essential for calculating heart rates and identifying any arrhythmias.

This measurement allows for consistent tracking of heart rhythm and helps in assessing the regularity of heartbeats. Using other waveforms like the P waves or T waves does not provide the same reliable information about the intervals between ventricular contractions, as these waves correspond to different phases of the cardiac cycle. Therefore, comparing the R waves is the most effective method for evaluating the timing between heartbeats.