scholarly journals A 50 Hz magnetic field affects hemodynamics, ECG and vascular endothelial function in healthy adults: A pilot randomized controlled trial

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0255242
Author(s):  
Hideyuki Okano ◽  
Akikatsu Fujimura ◽  
Tsukasa Kondo ◽  
Ilkka Laakso ◽  
Hiromi Ishiwatari ◽  
...  
Keyword(s):  
Blood Flow ◽  
Endothelial Function ◽  
Controlled Trial ◽  
Oxygenation Index ◽  
Arterial Blood Flow ◽  
Vascular Endothelial ◽  
Vascular Endothelial Function ◽  
Upper Arm ◽  
Arterial Blood ◽  
Sham Exposure

Application of exposure to 50/60 Hz magnetic fields (MFs) has been conducted in the treatment of muscle pain and fatigue mainly in Japan. However, whether MFs could increase blood flow leading to muscle fatigue recovery has not been sufficiently tested. We investigated the acute effects of a 50 Hz sinusoidal MF at Bmax 180 mT on hemodynamics, electrocardiogram, and vascular endothelial function in healthy young men. Three types of regional exposures to a 50 Hz MF, i.e., forearm, upper arm, or neck exposure to MF were performed. Participants who received three types of real MF exposures had significantly increased ulnar arterial blood flow velocity compared to the sham exposures. Furthermore, after muscle loading exercise, MF exposure recovered hemoglobin oxygenation index values faster and higher than sham exposure from the loading condition. Moreover, participants who received real MF exposure in the neck region had significantly increased parasympathetic high-frequency activity relative to the sham exposure. The MF exposure in the upper arm region significantly increased the brachial artery flow-mediated dilation compared to the sham exposure. Computer simulations of induced in situ electric fields indicated that the order-of-magnitude estimates of the peak values were 100–500 mV/m, depending on the exposure conditions. This study provides the first evidence that a 50 Hz MF can activate parasympathetic activity and thereby lead to increase vasodilation and blood flow via a nitric oxide-dependent mechanism. Trial registration: UMIN Clinical Trial Registry (CTR) UMIN000038834. The authors confirm that all ongoing and related trials for this drug/intervention are registered.

scholarly journals Folic acid supplementation improves vascular endothelial function, yet not skin blood flow during exercise in the heat, in patients with heart failure

2018 ◽  
Vol 315 (4) ◽  
pp. R810-R819 ◽  
Author(s):  
Bryce N. Balmain ◽  
Ollie Jay ◽  
Norman R. Morris ◽  
Glenn M. Stewart ◽  
Kenji Shiino ◽  
...  
Keyword(s):  
Heart Failure ◽  
Blood Flow ◽  
Folic Acid ◽  
Endothelial Function ◽  
Skin Blood Flow ◽  
Heat Production ◽  
Folic Acid Supplementation ◽  
Vascular Endothelial ◽  
Vascular Endothelial Function ◽  
Metabolic Heat

Heart failure (HF) patients are susceptible to heat strain during exercise, secondary to blunted skin blood flow (SkBF) responses, which may be explained by impaired nitric oxide (NO)-dependent vasodilation. Folic acid improves vascular endothelial function and SkBF through NO-dependent mechanisms in healthy older individuals and patients with cardiovascular disease. We examined the effect of folic acid supplementation (5 mg/day for 6 wk) on vascular function [brachial artery flow-mediated dilation (FMD)] and SkBF responses [cutaneous vascular conductance (CVC)] during 60 min of exercise at a fixed metabolic heat production (300 ẆHprod) in a 30°C environment in 10 patients with HF (New York Heart Association Class I–II) and 10 healthy controls (CON). Serum folic acid concentration increased in HF [preintervention (pre): 1.4 ± 0.2; postintervention (post): 8.9 ± 6.7 ng/ml, P = 0.01] and CON (pre: 1.3 ± 0.6; post: 5.2 ± 4.9 ng/ml, P = 0.03). FMD improved by 2.1 ± 1.3% in HF ( P < 0.01), but no change was observed in CON postintervention ( P = 0.20). During exercise, the external workload performed on the cycle ergometer to attain the fixed level of heat production for exercise was similar between groups (HF: 60 ± 13; CON: 65 ± 20 external workload, P = 0.52). Increases in CVC during exercise were similar in HF (pre: 0.89 ± 0.43; post: 0.83 ± 0.45 au/mmHg, P = 0.80) and CON (pre: 2.01 ± 0.79; post: 2.03 ± 0.72 au/mmHg, P = 0.73), although the values were consistently lower in HF for both pre- and postintervention measurement intervals ( P < 0.05). These findings demonstrate that folic acid improves vascular endothelial function in patients with HF but does not enhance SkBF during exercise at a fixed metabolic heat production in a warm environment.

scholarly journals Application of shortwave diathermy to lower limb increases arterial blood flow velocity and skin temperature in women: a randomized controlled trial

2017 ◽  
Vol 21 (2) ◽  
pp. 127-137 ◽  
Author(s):  
Natanael Teixeira Alves De Sousa ◽  
Elaine Caldeira De Oliveira Guirro ◽  
João Guilherme Calió ◽  
Mariane Cristina De Queluz ◽  
Rinaldo Roberto De Jesus Guirro
Keyword(s):  
Randomized Controlled Trial ◽  
Blood Flow ◽  
Flow Velocity ◽  
Skin Temperature ◽  
Blood Flow Velocity ◽  
Lower Limb ◽  
Controlled Trial ◽  
Arterial Blood Flow ◽  
Randomized Controlled ◽  
Arterial Blood

scholarly journals P1333PULSE WAVE ANALYSIS UNDER THE CONDITIONS OF HIGH ARTERIAL FLOW: ASSESSMENT OF SHUNT FUNCTION AND REACTIVE HYPEREMIA

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Niklas Mueller ◽  
Joachim Streis ◽  
Sandra Müller ◽  
Hermann Josef Pavenstädt ◽  
Stefan Reuter ◽  
...  
Keyword(s):  
Blood Flow ◽  
Endothelial Function ◽  
Pulse Wave ◽  
Statistical Significance ◽  
Reactive Hyperemia ◽  
Duplex Sonography ◽  
Arterial Blood Flow ◽  
Reactive Hyperaemia ◽  
Arterial Blood ◽  
The Impact

Abstract Background and Aims Fistula-creation as well as reactive hyperaemia increase local arterial blood flow. We wanted to analyse the impact of these haemodynamic changes on pulse wave (PW) morphology to assess fistula- and endothelial function. Method We conducted a clinical pilot study including 56 patients with functioning forearm fistula. PW morphology in the A. brachialis was assessed tonometrically at the non-fistula and fistula arm using the SpygmoCor® device. We also performed a PW analysis on the non-fistula arm under the condition of reactive hyperaemia (possible in 43 patients). Duplex-sonography was used as a complementary and reference method. Results In comparison to measurements under physiologic conditions, both the fistula arm (a) and the non-fistula arm with reactive hyperemia (b) showed marked differences in the pulse wave morphology (figure). The changes in PW morphology were most prominent in the area of the diacrotic notch and could be assessed as the differences of the sum of the mean slope (Δλ in mmHg/ms) between the diacrotic notch and the main preceding and subsequent inflexion point. Measurement with duplex-sonography confirmed increased peak blood flow velocity in the arteria brachialis (ΔVmax in cm/s) under both conditions. Statistical significance could be proved for Δλ and for ΔVmax (table). Finally, bivariate regression analysis revealed a correlation of Δλ with ΔVmax (figure; c: p=0.001 and r=-0,483 for interarm-differences of the fistula and non-fistula arm; d: p= 0.030 and r=-0.343 for the differences between the physiologic state and reactive hyperaemia at the non-fistula arm). Conclusion PW analysis under high flow conditions has the potential to be a new useful clinical tool in nephrology to monitor fistula- as well as endothelial function assessed by reactive hyperaemia. The findings should be verified in a trial with clinical endpoints.

Episodic bouts of hyperaemia and shear stress improve arterial blood flow and endothelial function

2018 ◽  
Vol 118 (4) ◽  
pp. 795-803 ◽  
Author(s):  
Gary J. Hodges ◽  
Desmond G. Stewart ◽  
Paul J. Davison ◽  
Stephen S. Cheung
Keyword(s):  
Blood Flow ◽  
Shear Stress ◽  
Endothelial Function ◽  
Arterial Blood Flow ◽  
Arterial Blood
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