Very Low and High Blood Viscosity are Risk Factors for Internal Flow Choking Causing Asymptomatic Cardiovascular Disease

It is well known that the common aftereffect of administration with the blood-thinning-drug for 24 lowering the blood-viscosity is bleeding. And very often during the blood-thinning medication, 25 without any preceding symptoms, asymptomatic-hemorrhage (AH) and the acute-heart-failure 26 (AHF) are testified. Of late (2021) researchers reported (PMID: 34326352) that symptoms are 27 intensifying on asymptomatic cardiovascular-diseases and the various types of neurological- 28 disorders linked with COVID-19 pandemic due to the nanoscale Sanal-flow-choking. aim and viz., the pressure ratio density, stenosis terms vessel cross-sectional hydraulic fraction terms fluid flow In this regard an infallible closed-form analytical model We also We critical for We establish the lopsided blood-thinning enhances the of the Sanal-flow-choking the blockage (BLB) by the blood-viscosity and flow increasing thermal- tolerance-level BHCR Herein, we established the proof of the concept of internal flow choking in CVS causing cardiovascular risk through the closed-form analytical, in vitro and in silico methods. An over dose of blood-thinning drug will enhance the Reynolds number , which creates high turbulence level causing an augmented boundary layer blockage factor leading to an early undesirable biofluid/Sanal flow choking at a critical blood-pressure-ratio (BPR). The fact is that in nanoscale 81 vessels when the pressure of fluid increases, average-mean-free-path decreases and thus, the Knudsen number reduces. It leads to the physical situation of no-slip boundary condition with 83 compressible-viscous flow effect. Sanal-flow-choking is a compressible-viscous flow effect establishing a physical condition of the sonic-fluid-throat, at a critical blood pressure ratio (BPR). We concluded that asymptomatic-hemorrhage (AH) and acute-heart-failure (AHF) are 86 transient-events as a result of internal flow-choking in nanoscale and/or large vessels followed by the shock wave creation and transient pressure-overshoot. We concluded that cardiovascular risk could be reduced by simultaneously lessening the blood-viscosity and flow turbulence by BHCR


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The theoretical discovery of the nanoscale Sanal-flow-choking [1] is a paradigm shift in risk 93 assessment for hemorrhagic stroke and other neurological disorders. This study is the 94 continuation of our previous work published in Nature Scientific Reports [1]. Of late (2021) 95 researchers reported that data are increasing on the various asymptomatic cardiovascular 96 diseases associated with COVID-19 pandemic [1][2][3] Fig. 1(a-c)), viz., (i) biofluid/blood flow choking due to 103 plaque or stenosis or occlusion (i.e., geometry effect of vessels), (ii) Sanal flow choking due to 104 boundary layer blockage (i.e., fluid dynamics effect) [11]. 105 The acute-heart-failure (AHF) is known as the fatal disease worldwide over the centuries.     Fig.1(a-c) and Fig.2(a-o)). It is followed by shock wave generation and pressure-146 overshoot in the cardiovascular system (CVS), which happens at a critical systolic-to-diastolic 147 blood-pressure-ratio (BPR). 148 Internal flow choking could occur without prejudice to the Percutaneous Coronary 149 Intervention (PCI). The real scientific truth is that, at a critical BPR, the internal flow choking    BHCR UCHI 190 Note that for prohibiting the internal flow choking in CVS all subjects must maintain BPR lower The earlier researchers, all together, presumed that the human blood is an incompressible fluid 208 (i.e., Cp = Cv). Such an assumption is obviously not true as the human blood specific volume (or    The BLB factor in the blood vessels could alter due to the seasonal effects (see Fig.3(a)) as 225 a result of the variations in the biofluid/blood viscosity [4][5][6][7][8][9][10][11][12][13][14][19][20][21][22][23][24]. If the blood vessel 226 geometry is similar to the convergent-divergent (CD) nozzle shape (due to various physical 227 situations as seen in Fig. 1(a-c) & Fig. 2(a-o)), the divergent region of the CD duct creates   Further discussion on in silico model is beyond the scope of this paper.    Electron Impact detector. During our comprehensive in vitro studies, we have noticed that the 315 gases evolved from the fresh blood sample depends on the blood temperature, the heating rate, 316 blood group, age and the blood pressure value. It is evident from Fig.4(c) that CO2 is the 317 dominant gas for human being whereas nitrogen gas is dominant (Fig.4(a)) in the blood sample 318 of Guinea pig.

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The estimated LCHI of all healthy human being is found 1.82, which is based on the evolved  healthy Guinea pig blood is higher than the healthy human being. The BHCR of healthy subjects 379 taken from the EDTA and Lithium Heparin tubes was found significantly lower (31-32 %) than 380 the fresh blood samples of the same healthy subjects tested within 5 minutes of collection. We 381 observed that CO2, the gas with the lowest HCR is relatively and consistently higher in the 382 healthy males than the healthy male Guinea pig of four weeks old (see Fig.4

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We discovered that at a critical blood-pressure-ratio (BPR), the internal-flow-choking occurs is not required any verification using in vitro data. Nevertheless, in vitro data generated from 434 the blood sample test of healthy subjects provided herein for corroborating our theoretical 435 discovery. In vitro data is also used for establishing the unchoked flow condition in healthy 436 subjects having relatively high BPR (> 1.8257) and BHCR (see Table- Iran. Note that if BHCR is relatively low (i.e., low thermal tolerance) blood will get vaporize 452 early in Covid-19 patients and others leading to gas embolism. At this condition if BPR is 453 increasing the chances of asymptomatic cardiovascular diseases will be high due to the 454 undesirable internal flow choking. Therefore, increasing the thermal tolerance level in terms of BHCR and/or decreasing the BPR is a possible remedy for negating the internal flow choking 456 causing AH and AHF. We discovered through analytical methodology that BHCR is a unique 457 parameter, which can control concurrently blood viscosity and turbulence. Briefly, high BHCR 458 reduces blood viscosity and turbulence.

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Generally, we consider blood flow is laminar in the CVS. The fact is that blood flow 460 becomes turbulent while taking blood thinning drugs. It is well known that the blood thinning  The first author thanks to SERB/DST, the Government of India, AIIMS, New Delhi and 606 NCCRD/IISc, Bangalore, India for the fruitful and coherent conclusion of this study.

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Data availability statement 608 The data that support the findings of this study are available from the corresponding author upon 609 reasonable request.

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Code availability statement 611 The code used for generating the in silico results is available with the authors NC and AS. The 614 raw data required to reproduce the results are available with the corresponding author and could 615 be shared upon reasonable request.