Automated on-line measurement of electrophysiologic intervals during cardiac catheterization.

A small dedicated, computer-controlled waveform analyzer was used to automatically measure the R-R cycle length, low right atrium to His, and His to ventricle intervals obtained during electrophysiologic studies on 35 patients. These measurements were compared to intervals hand-measured separately and found to correlate well (0.92, 0.83, and 0.75, respectively). The sources of error, possible pitfalls, and future uses of this technique are discussed.