Abstract 13868: Effects of Chronic Electronic Cigarette Vapor Exposures on the Cardiovascular Function in Rats

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Wangde Dai ◽  
Jianru Shi ◽  
Juan Carreno ◽  
Lifu zhao ◽  
Michael T Kleinman ◽  
...  

Background: We investigated the effects of chronic electronic cigarettes with nicotine (E-Cig) exposure on cardiovascular function in rats. Methods: Adult Sprague Dawley rats were exposed to either pure air (n=10) or E-Cig (n=14) for 12 weeks. After 12 weeks of exposure, flow-mediated vasodilation was measured in anesthetized rats with ultrasound to measure femoral artery diameter. Femoral artery flow velocity was measured before and 5 minutes after reperfusion of a 5-minute femoral artery occlusion. Cardiac function was assessed by echocardiogram. A Millar catheter was used to record systemic arterial and LV pressures. Cardiac output was measured using a themodilution catheter. Results: The femoral artery internal diameter and blood flow velocity were comparable between the 2 groups before and after artery occlusion. However, in the E-cig group, blood flow velocity significantly decreased from 55.5 ± 5.2 cm/s prior to occlusion to 41.3 ± 4.1 cm/s after reperfusion (p = 0.005); it remained similar prior to (47.8 ± 3.4 cm/s) and after (47.8 ± 5.5 cm/s) occlusion in the air group. There were no statistically significant differences in left ventricular diastolic and systolic dimensions, LV fractional shortening, heart rate or mean blood pressure (80 ± 3 mmHg in air and 79 ± 5 mmHg in E-cig group) , LV end-diastolic pressure (Ped), end-systolic pressure (Pes), peak -dP/dt, Tau, or cardiac output (48.3 ± 3.3 ml/min in air and 47.6 ± 3.9 ml/min in E-cig group) between the E-Cig and the pure air group. There was a trend toward a reduction in peak LV +dP /dt in the E-Cig group (5574 ± 341 mmHg/s) compared to the air group (6166 ± 238 mmHg/s). LV weight and wall thickness were similar between groups. Conclusions: Twelve weeks of E-Cig exposure did not affect heart rate or blood pressure; but did tend to reduce contractility. E-cigarette exposure slowed the flow-mediated blood flow velocity probably at a microvascular level, possibly by altering endothelial function.

Inventions ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 65 ◽  
Author(s):  
Fiorency Santoso ◽  
Bonifasius Putera Sampurna ◽  
Yu-Heng Lai ◽  
Sung-Tzu Liang ◽  
Erwei Hao ◽  
...  

This study aimed to develop a simple and cost-effective method to measure blood flow in zebrafish by using an image-based approach. Three days post fertilization (dpf) zebrafish embryos were mounted with methylcellulose and subjected to video recording for tracking blood flow under an inverted microscope equipped with a high-speed CCD camera. In addition, Hoffman lens was used to enhance the blood cell contrast. The red blood cell movement was tracked by using the TrackMate plug-in in the ImageJ image processing program. Moreover, Stack Difference and Time Series Analyzer plug-in were used to detect dynamic pixel changes over time to calculate the blood flow rate. In addition to blood flow velocity and heart rate, the effect of drug treatments on other cardiovascular function parameters, such as stroke volume and cardiac output remains to be explored. Therefore, by using this method, the potential side effects on the cardiovascular performance of ethyl 3-aminobenzoate methanesulfonate (MS222) and 3-isobutyl-1-methylxanthine (IBMX) were evaluated. MS222 is a common anesthetic, while IBMX is a naturally occurring methylxanthine. Compared to normal embryos, MS222- and IBMX-treated embryos had a reduced blood flow velocity by approximately 72% and 58%, respectively. This study showed that MS222 significantly decreased the heart rate, whereas IBMX increased the heart rate. Moreover, it also demonstrated that MS222 treatment reduced 50% of the stroke volume and cardiac output. While IBMX decreased the stroke volume only. The results are in line with previous studies that used expensive instruments and complicated software analysis to assess cardiovascular function. In conclusion, a simple and low-cost method can be used to study blood flow in zebrafish embryos for compound screening. Furthermore, it could provide a precise measurement of clinically relevant cardiac functions, specifically heart rate, stroke volume, and cardiac output.


1989 ◽  
Vol 17 (5) ◽  
pp. 339-344 ◽  
Author(s):  
Ina van Dam ◽  
Ben Delemarre ◽  
Jeroen Hopman ◽  
Theo de Boo ◽  
Cuno Uiterwaal ◽  
...  

2019 ◽  
pp. 120-124
Author(s):  
Peter Novak

Small fiber neuropathy is associated with adrenergic failure. Anxiety is common and occasionally can be identified as a transient elevation of heart rate, blood pressure, and cerebral blood flow velocity.


1990 ◽  
Vol 68 (5) ◽  
pp. 2208-2213 ◽  
Author(s):  
K. H. McKeever ◽  
M. G. Skidmore ◽  
L. C. Keil ◽  
H. Sandler

Eight rhesus monkeys were used to study responses of radial artery blood flow velocity (RABFV) and heart rate (HR) to low (0 to -20 mmHg) and high (0 to -60 mmHg) ramp exposures during supine lower body negative pressure (LBNP). These levels were chosen to separate peripheral vascular responses associated with stimulation of low- and high-pressure baroreceptors. Four monkeys had efferent and afferent cardiac denervation by use of the Randall procedure with pharmacological (phenylephrine and atropine) verification. Animals were studied 3 wk after surgery to avoid reinnervation. Findings were compared with those of four identically treated intact animals. Denervated animals showed no change in RABFV or HR during low-level LBNP; however, HR increased significantly (P less than 0.05) when LBNP reached -50 mmHg and blood flow velocity also fell (P less than 0.05) starting at -30 mmHg pressure. In contrast, intact animals showed steady decreases in RABFV during both high- and low-pressure protocols, with HR showing a 6-beat/min increase (P less than 0.05) starting at -20 mmHg pressure. As with denervated animals, intact animals showed a more pronounced increase in HR after reaching a level of -60 mmHg suction. Cardiac output (electromagnetic flowmeter, ascending aorta) fell significantly in both groups starting at -30 mmHg pressure. Left ventricular pressure (Konigsberg pressure cell) in three intact animals showed a progressive fall in systolic pressure starting at -10 mmHg suction, which became significant at -55 mmHg pressure. These results demonstrate that cardiac denervation by use of the Randall technique significantly affects RABFV and HR responses to LBNP in rhesus monkeys. The lack of RABFV change during LBNP in denervated animals suggests that these changes coupled with HR response can be used as an effective method to verify the completeness of denervation of low-pressure baroreceptors in animals that have undergone intrapericardial denervation.


2019 ◽  
pp. 194-197
Author(s):  
Peter Novak

In this patient, the initial decline in blood pressure at the tilt onset was physiologic since it was accompanied by the decline in cerebral blood flow velocity and heart rate responses. The testing revealed normal autonomic functions. It is important always to check the raw data. Blood pressure from the finger cuff is not always accurate.


Cephalalgia ◽  
1997 ◽  
Vol 17 (6) ◽  
pp. 639-646 ◽  
Author(s):  
RM Dixon ◽  
HB Meire ◽  
DH Evans ◽  
H Watt ◽  
N On ◽  
...  

Members of the new class of antimigraine compounds, 5HT1B/1D agonists, as well as ergotamine, may cause vasoconstriction through stimulation of 5HT receptors on peripheral vessels. The cardiovascular effects of 20 mg oral zolmitriptan (Zomig, formerly 311C90), 2 mg oral ergotamine and the combination were assessed in a randomized double-blind, placebo-corirolled crossover study in 12 healthy subjects. Pharmacodynamic measures included oscillometric blood pressure, systolic blood pressure at the toe and arm using a strain gauge technique, stroke volume and cardiac output using bioimpedance cardiography, high-resolution ultrasound to measure brachial arterial diameter and a novel Doppler method to measure blood flow velocity. Both drugs produced small degrees of peripheral vasoconstriction, including increases in diastolic blood pressure and blood flow velocity and decreases in arterial diameter and toe-arm systolic pressure gradient. These effects were generally additive with the combination but of no clinical importance. There were no significant changes in cardiac output, stroke volume heart rate or ECG. Zolmitriptan, at eight times the likely therapeutic dose, was generally well tolerated both alone and in combination with ergotamine. Ergotamine had no clinically important effects on zolmitriptan pharmacokinetics. Ergotamine, migraine, peripheral vasculature, pharmacokinetics, zolmitriptan


2014 ◽  
Vol 121 (6) ◽  
pp. 1184-1193
Author(s):  
Jeffrey S. McKee ◽  
Barrett E. Rabinow ◽  
Justin R. Daller ◽  
Benjamin D. Brooks ◽  
Bernhard Baumgartner ◽  
...  

Abstract Background: Esmolol is marketed as a racemate (RS-esmolol) with hypotension being the most frequently reported adverse event. Previously, it has been shown that the S-enantiomer (S-esmolol) possesses all of the heart rate (HR) control. The authors studied whether S-esmolol alone mitigates hypotension at similar degrees of HR control compared with RS-esmolol. Methods: The effects of RS- and S-esmolol on blood pressure (BP) were compared at multiple infusion rates producing similar HR control in dogs (N = 21). Differences in BP were further interrogated by monitoring global cardiovascular function and included the R-enantiomer (R-esmolol) (N = 3). Results: S-esmolol at half the rate (μg kg−1 min−1) of RS-esmolol provided the same degree of HR control over all infusion rates. RS-esmolol lowered BP by 3, 6, 11, 20, and 38 mmHg at 90, 300, 600, 1,000, and 2,000 μg kg−1 min−1, compared with 2, 4, 5, 10, and 16 mmHg at 45, 150, 300, 500, and 1,000 μg kg−1 min−1 for S-esmolol. Decreased BP with RS-esmolol was attributed to decreases in left ventricular developed pressure (LVDP) (−34 mmHg), LVdP/dt+max (−702 mmHg/s), and cardiac output (−1 l/min). R-esmolol also decreased BP (−10 mmHg), LVDP (−10 mmHg), LVdP/dt+max (−241 mmHg/s), and cardiac output (to −0.2 l/min). S-esmolol reversed these trends toward pre-esmolol values by increasing BP (+13 mmHg), LVDP (+12 mmHg), LVdP/dt+max (+76 mmHg/s), and cardiac output (+0.4 l/min). Conclusions: R-enantiomer provided no HR control, but contributed to the hypotension with RS-esmolol, which appears to be due to negative inotropy. Thus, an S-enantiomer formulation of esmolol may provide similar HR control with less hypotension.


2010 ◽  
Vol 298 (2) ◽  
pp. F279-F284 ◽  
Author(s):  
Erin E. Conboy ◽  
Amy E. Fogelman ◽  
Charity L. Sauder ◽  
Chester A. Ray

Endurance training has been associated with increased orthostatic intolerance. The purpose of the present study was to test the hypothesis that endurance training reduces renal vasoconstriction to orthostatic stress. Blood pressure, heart rate, and renal blood flow velocity were measured during a 25-min 60° head-up tilt (HUT) test before and after 8 wk of endurance training in eight healthy sedentary subjects (26 ± 1 yrs). Training elicited a 21 ± 3% increase in peak oxygen uptake (V̇o2peak) and a reduction in heart rate at rest of 8 ± 2 beats/min. During HUT, heart rate progressively increased (∼20 beats/min) over the 25-min HUT trial both before and after training. Systolic arterial blood pressure during HUT was unchanged with training, whereas diastolic arterial blood pressure was lower at the end of HUT after training. Before training renal blood flow velocity (Δ14 ± 5 cm/s) and renal vascular conductance (Δ22 ± 7%) decreased during HUT, whereas after training renal blood flow velocity (Δ2 ± 5 cm/s) and renal vascular conductance (Δ1 ± 12%) did not change significantly during HUT. Renal blood flow velocity and vascular conductance responses to HUT did not change in control subjects during the 8-wk period. These results demonstrate that endurance training reduces renal vasoconstriction during an orthostatic challenge and may contribute to training-induced orthostatic intolerance.


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