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Circahoralian rhythms in assessment of heart rate variability
S S Zaguskina1, S L Zaguskin, Y V Gurov
1Laboratory of Biophysics and Chronobiology, Physics Research Institute, South Federal University, Rostov-on-Don, Russia.
Abstract:
Circahoralian oscillations of various indices describing variations of interpulse, respiratory, and R-R intervals were recorded in normal subjects, in hypertensive patients, and in patients rehabilitating after cardiac infarction. The parameters of these rhythms reflect changes in the status of autonomic nervous system, correlate with pathological disturbances in circadian rhythm, and accompany the sleep-wake and wake-sleep transitions. In assessment of circadian rhythm parameters, the most informative are the plots of changes in Pierson correlation coefficients of interpulse and R-R intervals. The 5-min ECG segments recorded at various phases of circahoralian rhythm are subjected to circahoralian variations and can distort diagnostics.
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