RT Book, Section A1 Stein, Phyllis K. A1 Pantazopoulos, Panagiotis A2 Pahlm, Olle A2 Wagner, Galen S. SR Print(0) ID 8763541 T1 Chapter 16. Graphical Analysis of Heart Rate Patterns to Assess Cardiac Autonomic Function T2 Multimodal Cardiovascular Imaging: Principles and Clinical Applications YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-161346-0 LK accessmedicine.mhmedical.com/content.aspx?aid=8763541 RD 2024/03/28 AB A continuous electrocardiogram, whether from a Holter recording, an intensive care unit monitor, an overnight polysomnogram, or even a short-term recording, provides a signal that can yield information about the morphology and time of onset of each heartbeat. This information, exported as a "beat file" provides the basis for multiple ways of quantifying and categorizing heart rate variability (HRV), in most cases based on intervals between normal to normal (N-N) heartbeats only. The various methods for quantifying HRV (eg, time domain, frequency domain, nonlinear) and their relationship to cardiac autonomic function have been described in multiple excellent reviews elsewhere.1-3 Less appreciated is the power of using graphical images, also derived from beat files, to obtain information about normal and abnormal cardiac autonomic function, sinus node function, and sleep-disordered breathing.