PR and PP ECG interval variation during obstructive apnea and hypopnea

A method to elucidate PP and PR electrocardiogram variability during periods of obstructive apnea based on averaged interval length is considered. R and P peaks are extracted from 28 pediatric subjects´ ECG signal using a Hilbert transform based technique. Visual analysis of phasic changes during obstructive events indicate that 21 of 28 of subjects exhibit opposite changes in PP and PR interval length after apnea onset. This suggests that changes in PR interval are primarily refractory influenced. In subjects with severe obstructive apnea, apneas are also associated with prolonged cyclical variations in PP interval (and to a lesser extent in PR).