Prolonged space flight impacts how the heartbeat influences venous circulation between the heart and the brain. This is revealed by a University of Ferrara study published in Scientific Report that for the first time characterized the jugular venous pulse during long-duration space trips. The findings show that in the absence of the Earth's hydrostatic gradient, the heart's oscillations can propagate more intensely toward the cerebral venous compartment. The study included four astronauts who were checked before and after a long-duration space mission; for one of them, measures acquired while in orbit were also analyzed. Researchers found a substantial reduction in the mean area of the internal jugular vein in three astronauts following their mission. In two astronauts, the pulsatile excursion, which is the difference between the maximal and minimum expansion of the vessel during the cardiac cycle, also increased significantly: 105% and 337%, respectively, in comparison to pre-mission values. "Although the study is constrained by the small number of astronauts evaluated, the findings enable us to develop ideas that can be tested in future experiments. The goal is to determine whether and how the observed phenomena is related to the neurological problems that astronauts experience during long-duration missions", says Professor Paolo Zamboni, a professor at the University of Ferrara and the study's first author. According to the authors, eliminating the hydrostatic gradient on Earth results in greater transmission of heart pressure waves to the cerebral venous compartment. Even in microgravity, the form of the venous pulse and its coordination with the cardiac cycle are discernible. The automated approach utilized in the study allows us to calculate the jugular venous pulse from brief ultrasound sequences and could be used as a clinical assistance tool.