[Individual prediction by the analysis of preflight ECG data of cardiac function disorders in cosmonauts during standard deorbit after long-term space flights and in the period of postflight observation].

ECG records of 25 cosmonauts--members of 30 long-term Mir and ISS missions (73- to 197-day long) in the period of 1995-2007 were analyzed. The ECG records were made during medical selection, clinical-physiological investigations (KFO) before launch, insertion and standard descent, and post-flight KFO. No negative trends were discovered in 70% (n=21) of ECG records during insertion and descent of cosmonauts who had not have significant ECG deviations before flight.

[Prediction of cardiac function deviations (ECG data) in the course of permanent cosmonaut's monitoring starting from selection till return to earth after short-duration space flight].

Analyzed were deviations in cardiac function in 29 cosmonauts with previous aviation and other occupations ranging of 29 to 61 y.o. who made 8- to 30-day space flights (totai number of flights = 34) between 1982 and 2006.

[Possibility to predict cosmonauts' orthostatic tolerance following short-and long-term space flights].

According to the analysis of the data of active and passive orthostatic tolerance (OST) testing before and after 67 short- (SSF) and 53 long-term (LSF) space flights OST declined in all the cosmonauts regardless of flight length. Active testing on R+1 after SSF (7 to 25 d) and LSF (49 to 438 d) attested OST loss by 33% and 48%, respectively. Full OST recovery following SSF and LSF was observed in a week and 1.

Changes in hemodynamic and post-flights orthostatic tolerance of cosmonauts under application of the preventive device--thigh cuffs bracelets in short-term flights.

to evaluate the influence of the use thigh cuffs "Bracelet" on the hemodynamic adaptation to microgravity during short-term (up to a month) space flights, in-flight tolerance to LBNP-tests and post-flight orthostatic tolerance. 6 cosmonauts applied and 7 others did not apply the occlusive cuffs when on flight. The "Bracelet" device notably relieved the cosmonauts from the subjective discomfort following by the blood redistribution at initial period of exposure to microgravity.

[Relationship between the hemodynamic disorders in cosmonauts on short-term space flights and orthostatic stability].

Comparative investigation of the hemodynamic responses of cosmonauts at rest, during occlusive leg plethysmography, and LBNP in relatively short (less than a month) space flights were performed to tie up these measurements with post-landing orthostatic stability (OS). The decreased LBNP tolerance in flight that correlated later on with impaired reactions to both active and passive orthostatic testing are attributed, among other reasons, to deficient vasoconstriction of the main arteries and over-extendibility of veins in the lower extremities. Results of ultrasonic investigations of hemodynamics during LBNP tests before and after space flight and data of leg venous extension in SF can and should be used in predicting cosmonaut's orthostatic status post flight.

[Effects of occlusive cuffs "Braslet" on crew hemodynamics in short space flights and orthostatic stability post flight].

Effects of prophylactic device Braslet (occlusive cuffs wrapped around the calf) on hemodynamics were studied at rest and during the LBNP test during and on orthostatic stability post short (one-month) space flights. The ultrasonic procedure was applied to seven cosmonauts who had and six cosmonauts who had not worn the cuffs while in orbit. The device markedly alleviated the subjective feeling of discomfort caused by blood shift toward the cranial end at the beginning of adaptation to microgravity.

[Human cardiac activity during the 1st hours and days of exposure to antiorthostatic hypokinesia (according to the results of echocardiography)].

Six healthy volunteers (aged 19-24) were exposed to head-down tilt (at-10 degrees) for 7 days. The study revealed phasic changes of intracardiac circulation and the pump function which were not accompanied by contractility disorders. On the whole, the changes represented a manifestation of cardiovascular adaptation to hemodynamic shifts that are typical of this type of simulated weightlessness.

[Postural reactions in cosmonauts after long flights aboard Salyut-6].

Tilt tests were used to study changes in cardiovascular responses to ortho- and antiorthostasis of four cosmonauts after their 96- and 140-day flights onboard Salyut-6. Preflight the cosmonauts were exposed to head-up and head-down tests in order to facilitate their readaptation to weightlessness. Postflight all cosmonauts exhibited a better cardiovascular capability to counteract cranial blood redistribution during antiorthostatic tilt tests.

[Evaluation of the antiorthostatic reactions of the cerebral circulation].

On the basis of experiments on 122 healthy male test subjects the norms of reactions of cerebral circulation to antiorthostatic exposures, basic principles and evaluations of its antiorthostatic tolerance (AOT) were established. The level of AOT was found to increase in acrobats in the course of their training, in test subjects after 30-day head-down tilting, and in space crewmen postflight. This increase can be regarded as an adaptive reaction of cerebral circulation to the excess blood rush to the head both on the Earth and in weightlessness.

[Orthostatic stability in cosmonauts following 30- and 63-day flights in orbital station "Salyut-4"].

Reactions of the circulation system of cosmonauts to the up and down body movements were studied after 30-day and 63-day flights. All the four cosmonauts showed a decline in the orthostatic tolerance. An improved system of countermeasures against unfavourable effects of weightlessness used in the 63-day flight helped to maintain a better orthostatic tolerance of the crewmembers than that of the 30-day cosmonauts.