Thigh Cuff Effects on Venous Flow Redistribution During 4 Days in Dry Immersion

2020 ◽  
Vol 91 (9) ◽  
pp. 697-702
Author(s):  
Philippe Arbeille ◽  
Danielle Greaves ◽  
Laurent Guillon ◽  
Stephane Besnard
Keyword(s):  
Left Ventricle ◽  
Ejection Fraction ◽  
Jugular Vein ◽  
Residual Effect ◽  
Cerebral Vein ◽  
Fluid Shift ◽  
Venous Flow ◽  
Additional Measure ◽  
Dry Immersion ◽  
Vein Diameter

PURPOSE: The objective was to quantify the venous redistribution during a 4-d dry immersion (DI) and evaluate the effect of thigh cuffs.METHODS: The study included nine control (Co) and nine subjects wearing thigh cuffs during the daytime (CU). Ultrasound measures were performed Pre-DI, on day 4 AM (D4 AM) and D4 PM: left ventricle stroke volume and ejection fraction (SV, EF), jugular vein volume (JVvol), portal vein diameter (PV), and middle cerebral vein velocity (MCVv). An additional measure of JVvol was performed on Day 1 after 2 h in DI.RESULTS: After 2 h in DI, JVvol increased significantly from Pre in both groups, but increased more in the Co compared to the CU subjects (Co: 0.27 0.15 cm3 to 0.94 0.22 cm3; CU: 0.32 0.13 cm3 to 0.64 0.32 cm3). At D4 AM, SV and EF decreased from Pre (SV: 111 23 cm3 to 93 24 cm3; EF: 0.66 0.07 to 0.62 0.07). JVvol was slightly increased (Co: 0.47 0.22 cm3 CU: 0.35 014 cm3). MCVv and PV remained unchanged from Pre-DI. No difference was found between the two groups for any of the parameters measured. From D4 AM to PM, no significant change was observed for any parameter.CONCLUSION: The results confirm that DI induces, during the first 2-3 h, a significant cephalic fluid shift as observed in spaceflight. During this early phase, the thigh cuffs reduced the amplitude of the fluid shift toward the head, but after 4 d in DI there was only a slight memory (residual) effect of DI on the jugular volume and no residual effect of the thigh cuffs.Arbeille P, Greaves D, Guillon L, Besnard S. Thigh cuff effects on venous flow redistribution during 4 days in dry immersion. Aerosp Med Hum Perform. 2020; 91(9):697702.

LLower body negative pressure reduces jugular and portal vein volumes, and counteracts the cerebral vein velocity elevation during long-duration spaceflight

2021 ◽  
Author(s):  
Philippe Arbeille ◽  
Kathryn A. Zuj ◽  
Brandon R. Macias ◽  
Douglas J. Ebert ◽  
Steven S. Laurie ◽  
...  
Keyword(s):  
Portal Vein ◽  
Negative Pressure ◽  
Jugular Vein ◽  
Lower Body Negative Pressure ◽  
Venous Blood ◽  
Upper Body ◽  
Cerebral Vein ◽  
Fluid Shift ◽  
Cross Sectional ◽  
Long Duration

Purpose: Cephalad fluid shifts in space have been hypothesized to cause the spaceflight-associated neuro-ocular syndrome (SANS) by increasing the intracranial-ocular translaminal pressure gradient. Lower body negative pressure (LBNP) can be used to shift upper-body blood and other fluids towards the legs during spaceflight. We hypothesized that microgravity would increase jugular vein volume (JVvol), portal vein cross-sectional area (PV), and intracranial venous blood velocity (MCV) and that 25mmHg LBNP application would return these variables towards preflight levels. Methods: Data were collected from 14 subjects (11 male) before and during long-duration ISS spaceflights. Ultrasound measures of JVvol, PV, and MCV were acquired while seated and supine before flight and early during spaceflight at days 45 (FD45) and late (FD150) with and without LBNP. Results: JVvol increased from preflight supine and seated postures (46 ± 48 % and 646 ± 595 % on FD45 and 43 ± 43 % and 702 ± 631 % on FD150, p<0.05), MCV increased from preflight supine 44 ± 31 % on FD45 and 115 ± 116 % on FD150 (p<0.05), PV increased from preflight supine and seated (51 ± 56 % and 100 ± 74 %) on FD150 (p<0.05). Inflight 25mmHg LBNP restored JVvol, and MCV to preflight supine and PV to preflight seated level. Conclusions: Elevated JVvol confirms the sustained neck-head blood engorgement inflight, while increased PV area supports the fluid shift at the splanchnic level. Also, MCV increased potentially due to reduced lumen diameter. LBNP, returning variables to preflight levels, may be an effective countermeasure.

New Hybrid Method for Left Ventricular Ejection Fraction Assessment from Radionuclide Ventriculography Images

2020 ◽  
Vol 16 ◽  
Author(s):  
Halima Dziri ◽  
Mohamed Ali Cherni ◽  
Dorra Ben Sellem
Keyword(s):  
Left Ventricular Ejection Fraction ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Positive Predictive Value ◽  
Roc Curve ◽  
Radionuclide Ventriculography ◽  
Left Ventricular ◽  
The Other ◽  
Left Ventricular Ejection ◽  
Ventricular Ejection Fraction

Background: In this paper, we propose a new efficient method of radionuclide ventriculography image segmentation to estimate the left ventricular ejection fraction. This parameter is an important prognostic factor for diagnosing abnormal cardiac function. Methods: The proposed method combines the Chan-Vese and the mathematical morphology algorithms. It was applied to diastolic and systolic images obtained from the Nuclear Medicine Department of Salah AZAIEZ Institute.In order to validate our proposed method, we compare the obtained results to those of two methods of the literature. The first one is based on mathematical morphology, while the second one uses the basic Chan-Vese algorithm. To evaluate the quality of segmentation, we compute accuracy, positive predictive value and area under the ROC curve. We also compare the left ventricle ejection fraction estimated by our method to that of the reference given by the software of the gamma-camera and validated by the expert, using Pearson’s correlation coefficient, ANOVA test and linear regression. Results and conclusion: Static results show that the proposed method is very efficient in the detection of the left ventricle. The accuracy was 98.60%, higher than that of the other two methods (95.52% and 98.50%). Likewise, the positive predictive value was the highest (86.40% vs. 83.63% 71.82%). The area under the ROC curve was also the most important (0.998% vs. 0.926% 0.919%). On the other hand, Pearson's correlation coefficient was the highest (99% vs. 98% 37%). The correlation was significantly positive (p<0.001).

scholarly journals The influence of afterload on left ventricular contractility: 2D-strain and dyssynchrony in stress echocardiography

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
E Karev ◽  
S Verbilo ◽  
E Malev ◽  
M Prokudina ◽  
A Suvorov
Keyword(s):  
Coronary Artery ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Stress Echocardiography ◽  
Longitudinal Strain ◽  
Wall Motion ◽  
Wall Motion Score Index ◽  
Wall Motion Abnormalities ◽  
Response To Exercise ◽  
Score Index

Abstract Funding Acknowledgements Type of funding sources: None. Background Hypertensive response to exercise (HRE) has negative prognostic value but its impact on the  left ventricle (LV) contractility and on stress echocardiography (SE) results remains controversial. The global longitudinal strain (GLS) and LV dyssynchrony changes in response to afterload increase were shown even in patients with narrow QRS at rest, but not on exertion. Purpose We aimed to analyze the relation between the blood pressure (BP) during SE and LV GLS and dyssynchrony changes. Methods We performed exercise SE on treadmill in 96 patients without coronary artery stenosis (invasive or CT coronary angiography). Patients divided into two groups: HRE (n = 41) and normal response to exercise (NRE) (n = 55). We analyzed GLS and standard deviation of time between the onset of QRS and segmental longitudinal strain peaks (STE-TIME SD) using speckle tracking and 3d-ejection fraction (EF) at rest and on exertion. Results 2D-EF increase was higher in patients with NRE, but 3D-EF did not differ between groups. Wall motion abnormalities (WMA) on peak stress were detected more often in patients with HRE who had higher wall motion score index (WMSI). GLS on exertion and its increment were lower in HRE group (Fig. 1 - "Bull’s eye" diagrams of GLS at rest and on exertion in patient with NRE (upper panel) and HRE (lower panel)). Among dyssynchrony markers we revealed higher values of STE-TIME SD on exertion in HRE group (Table 1). Moreover the analysis showed positive correlations between BP level on exertion and peak GLS (r = 0.56, p &lt; 0.0001), GLS increase (r = 0.54, p &lt; 0.0001) and STE-TIME SD on exertion (r = 0.27, p &lt; 0.02) Conclusions HRE is associated with less increment in GLS and 2D-EF on exertion. Besides LV dyssynchrony signs can appear in response to exaggerated afterload increase even in patients with narrow QRS complexes. Patients with HRE more often show stress-induced WMA and have greater WMSI on exertion in absence of coronary artery lesions, thus HRE can alter the specificity of the test in transient ischemia detection. Table 1 HRE NRE p Δ-2D ejection fraction 5.0 (4.0; 7.0) 10.0 (8.0; 12.5) &lt;0.0000001 Δ-3D ejection fraction 8.25 (4.0; 8.25) 8.24 (8.15; 11.65) 0.09 Wall motion abnormalities on exertion 46.34% 1.8% &lt;0.00001 Wall motion score index 1.0 (1.0; 1.18) 1.0 (1.0; 1.0) 0.00013 GLS on exertion -21.0 (-22.0; -19.0) -24.0 (-26.5; -23.0) &lt;0.0000001 ΔGLS 0.0 (-1.0; 2.0) 4.0 (2.0; 6.0) &lt;0.0000001 STE-TIME SD-IMPOST 42.0 (35.0; 53.0) 35.0 (27.5; 45.0) 0.012 Left ventricle systolic function and dyssynchrony in two groups. Abstract Figure 1.

scholarly journals The Mediterranean Diet Benefit on Cardiovascular Hemodynamics and Erectile Function in Chronic Heart Failure Male Patients by Decoding Central and Peripheral Vessel Rheology

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 108
Author(s):  
Athanasios Angelis ◽  
Christina Chrysohoou ◽  
Evangelia Tzorovili ◽  
Aggeliki Laina ◽  
Panagiotis Xydis ◽  
...  
Keyword(s):  
Heart Failure ◽  
Chronic Heart Failure ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Mediterranean Diet ◽  
Serum Prolactin ◽  
Doppler Velocity ◽  
Heart Failure Patients ◽  
Cardiovascular Hemodynamics ◽  
The Mediterranean

Background: Mediterranean diet was evaluated on erectile performance and cardiovascular hemodynamics, in chronic heart failure patients. Methods: 150 male stable heart failure patients were enrolled in the study (62 ± 10 years, New York Heart Association (NYHA) classes I–II, ejection fraction ≤40%). A detailed echocardiographic evaluation including estimation of the global longitudinal strain of the left ventricle and the systolic tissue doppler velocity of the tricuspid annulus was performed. Erectile dysfunction severity was assessed by the Sexual Health Inventory for Men-5 (SHIM-5) score. Adherence to the Mediterranean diet was evaluated by the MedDietScore. Results: The SHIM-5 score was positively correlated with the MedDietScore (p = 0.006) and augmentation index (p = 0.031) and inversely correlated with age (p = 0.002). MedDietScore was negatively associated with intima-media-thickness (p < 0.001) and serum prolactin levels (p = 0.05). Multi-adjusted analysis revealed that the inverse relation of SHIM-5 and prolactin levels remained significant only among patients with low adherence to the Mediterranean diet (p = 0.012). Conclusion: Consumption of Mediterranean diet benefits cardiovascular hemodynamics, while suppressing serum prolactin levels. Such physiology may enhance erectile ability independently of the of the left ventricle ejection fraction.

scholarly journals Left ventricle ejection fraction may predict mortality in renal transplant patients

Renal Failure ◽  
2016 ◽  
Vol 38 (10) ◽  
pp. 1622-1625 ◽  
Author(s):  
Faruk Ozkul ◽  
Muhammmet Kasim Arik ◽  
Halil Erbiş ◽  
Alpaslan Akbaş ◽  
Vural Taner Yilmaz ◽  
...  
Keyword(s):  
Renal Transplant ◽  
Left Ventricle ◽  
Ejection Fraction ◽  
Left Ventricle Ejection Fraction ◽  
Transplant Patients ◽  
Renal Transplant Patients

scholarly journals How to deal with low-flow low-gradient aortic stenosis and reduced left ventricle ejection fraction: from literature review to tips for clinical practice

2021 ◽  
Author(s):  
F. Contorni ◽  
M. Fineschi ◽  
A. Iadanza ◽  
A. Santoro ◽  
G. E. Mandoli ◽  
...  
Keyword(s):  
Aortic Valve ◽  
Left Ventricle ◽  
Aortic Stenosis ◽  
Ejection Fraction ◽  
Left Ventricle Ejection Fraction ◽  
Low Flow ◽  
Diagnostic Tools ◽  
Transcatheter Aortic Valve ◽  
Valve Implantation

AbstractLow-flow low-gradient aortic stenosis (LFLG AS) with reduced left ventricle ejection fraction (LVEF) is still a diagnostic and therapeutic challenge. The aim of this paper is to review the latest evidences about the assessment of the valvular disease, usually difficult because of the low-flow status, and the therapeutic options. Special emphasis is given to the available diagnostic tools for the characterization of LFLG AS without functional reserve at stress echocardiography and to the factors that clinicians should evaluate to choose between surgical aortic valve repair, transcatheter aortic valve implantation, or medical therapy.

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