Document Type


Date of Award

Spring 5-31-1994

Degree Name

Master of Science in Biomedical Engineering - (M.S.)


Biomedical Engineering Committee

First Advisor

Stanley S. Reisman

Second Advisor

David S. Kristol

Third Advisor

Thomas W. Findley


A method was developed to derive the respiration signal from the ECG signal based on the observation that the body-surface ECG is influenced by electrode motion relative to the heart and that fluctuations in the mean cardiac electrical axis accompany respiration. S-Plus programs were developed to calculate the changes in the value of the mean cardiac electrical axis during respiration from a two lead ECG signal and to generate a continuous ECG-derived respiratory signal from the angle information.

Data were taken from 9 healthy subjects during rest, paced breathing and exercise. The respiration was derived from the recorded ECG signals. The ECG-derived respiration was compared with the original respiration recorded through an impedance pneumography device. The derived respiration shows an excellent correspondence with the original respiration. Statistical analysis indicates that the ECG-derived respiration has a high correlation with the original respiration in the frequency domain.

Our study provides a method to obtain the respiration from the ECG signal when respiration information is not directly available. This can be done either directly or from a Holter recording. It is therefore possible to do spectral analysis of heart rate variability and determine the frequency of the spectral peak occurring at the respiration frequency.