In vitro prediction of the lower/upper-critical biofluid flow choking index and in vivo demonstration of flow choking in the stenosis artery of the animal with air embolism

Diagnostic investigations of aneurysm, hemorrhagic stroke, and other asymptomatic cardiovascular diseases and neurological disorders due to the flow choking (biofluid/boundary layer blockage persuaded flow choking) phenomenon in the circulatory system of humans and animals on the Earth and in the human spaceflight are active research topics of topical interest {Kumar et al., “boundary layer blockage persuaded flow choking leads to hemorrhagic stroke and other neurological disorders in earth and human spaceflight,” Paper presented at the Basic Cardiovascular Sciences Conference, 23–25 August 2021 (American Stroke Association, 2021) [Circ. Res. 129, AP422 (2021)] and “Lopsided blood-thinning drug increases the risk of internal flow choking and shock wave generation causing asymptomatic stroke,” in International Stroke Conference, 19–20 March 2021 (American Stroke Association, 2021) [Stroke 52, AP804 (2021)]}. The theoretical concept of flow choking [Kumar et al., “Lopsided blood-thinning drug increases the risk of internal flow choking leading to shock wave generation causing asymptomatic cardiovascular disease,” Global Challenges 5, 2000076 (2021); “Discovery of nanoscale boundary layer blockage persuaded flow choking in cardiovascular system—Exact prediction of the 3D boundary-layer-blockage factor in nanotubes,” Sci. Rep. 11, 15429 (2021); and “The theoretical prediction of the boundary layer blockage and external flow choking at moving aircraft in ground effects,” Phys. Fluids 33(3), 036108 (2021)] in the cardiovascular system (CVS) due to gas embolism is established herein through analytical, in vitro (Kumar et al., “Nanoscale flow choking and spaceflight effects on cardiovascular risk of astronauts—A new perspective,” AIAA Paper No. 2021-0357, 2021), in silico (Kumar et al., “Boundary layer blockage, Venturi effect and cavitation causing aerodynamic choking and shock waves in human artery leading to hemorrhage and massive heart attack—A new perspective,” AIAA Paper No. 2018-3962, 2018), and in vivo animal methodology [Jayaraman et al., “Animal in vivo: The proof of flow choking and bulging of the downstream region of the stenosis artery due to air embolism,” Paper presented at the Basic Cardiovascular Sciences Conference, 25–28 July 2022 (American Heart Association, 2022)]. The boundary layer blockage persuaded flow choking phenomenon is a compressible viscous flow effect, and it arises at a critical pressure ratio in continuum/non-continuum real-world