[Phase structure of the ejection period in the human cardiac function before and after 3-day water immersion].
Impedance cardiography was applied to 15 normal male volunteers before and after 3-d water immersion. Determined were parameters of central circulation and dependence of the ejection period on length of the cardiac cycle. Though the ejection period over the whole range of cardiac cycle lengths was shorter than "due" values determined as pre-immersion baseline, cardiac output after immersion was equal to and even slightly above baseline value. According to experimental results, this seems to be linked with little if any dependence of the fast ejection phase, hemodynamically most effective, on heart rate and volume loading which remained same as in the baseline period during all post-immersion tests. In contrast, the reduced ejection period, a variable of the ventricular blood evacuation, is materially dependent on heart rate and volume loading predetermining at large absolute and relative shortening of the ejection period after immersion.
Modin
A Iu
AIu
Aviakosmicheskaya i Ekologicheskaya Meditsina, Russia.
D002940:Circadian Rhythm / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007101:Immersion; D011187:Posture; D013997:Time Factors; D014867:Water
D014867:Water
Fazovaia struktura perioda izgnaniia v serdechnom tsikle cheloveka do i posle trekhsutochnoĭ vodnoĭ immersii.