Measure Of Wave Reflection Research Articles

Commentary: Acute Effects of Exercise Mode on Arterial Stiffness and Wave Reflection in Healthy Young Adults: A Systematic Review and Meta-Analysis.

We recently read the article, “Acute Effects of Exercise Mode on Arterial Stiffness and Wave Reflection in Healthy Young Adults: A Systematic Review and Meta-Analysis” by Doris R. Pierce, Kenji Doma and Anthony S. Leicht (volume 13, 2018). This particular article was a review and meta-analysis that focused on changes in arterial stiffness and measures of pulse wave reflection in response to different exercise modalities. The aim of this commentary is to highlight, and to make note, on some of the data that was presented in their manuscript. Increases in measures of pulse wave reflection, primarily the augmentation index (AIx), and the AIx at normalized to 75 beats per minute (AIx@75), are associated with increased cardiovascular mortality and morbidity (Weber et al., 2004). The AIx is defined as augmentation pressure expressed as a percentage of aortic pulse pressure. It is influenced by the timing and the amplitude of the forward traveling wave and the reflected wave (Wilkinson et al., 2000). Following resistance exercise there appears to be a significant impact on measures of pulse wave reflection (Fahs et al., 2009; Yoon et al., 2010; Kingsley et al., 2017; Tai et al., 2018). This is further supported by the meta-analysis of Pierce et al. (2018).

Augmentation index, a predictor of cardiovascular events, is increased in children and adolescents with primary nephrotic syndrome.

Arterial stiffness is associated with an increased risk of cardiovascular diseases. Augmentation index (AIx@75), a measure of arterial stiffness and wave reflection, has not been evaluated in patients with primary nephrotic syndrome (PNS). We investigated whether central and peripheral vascular profiles, hemodynamic parameters, and biochemical tests are associated with AIx@75 in PNS patients. This observational study involved 38 children and adolescents with PNS (12.14 ± 3.65years) and 37 healthy controls (13.28 ± 2.80years). Arterial stiffness and vascular and hemodynamic parameters were measured noninvasively using the Mobil-O-Graph® (IEM, Stolberg, Germany). In the PNS group, biochemical tests and corticosteroid dosage/treatment time were analyzed. Peripheral and central systolic blood pressure (SBPp, SBPc) Z-scores were significantly higher in the PNS patients. AIx@75 was significantly higher in the PNS patients (25.14 ± 9.93%) than in controls (20.84 ± 7.18%). In the control group, AIx@75 negatively correlated with weight (r = - 0.369; p = 0.025), height (r = - 0.370; p = 0.024), and systolic volume/body surface (r = - 0.448; p = 0.006). In the PNS group, a univariate linear correlation showed that AIx@75 negatively correlated with weight (r = - 0.360; p = 0.027), height (r = 0.381; p = 0.18), and systolic volume/body surface (r = - 0.447; p < 0.002) and positively with the Z-score of SBPp (r = 0.407; p = 0.011), peripheral diastolic blood pressure (DBPp, r = 0.452; p = 0.004), SBPc (r = 0.416; p = 0.009), DBPc (r = 0.407; p = 0.011), triglycerides (r = 0.525; p = 0.001), and cholesterol [total (r = 0.539; p < 0.001), LDLc (r = 0.420; p = 0.010), and non-HDLc (r = 0.511; p = 0.001)]. Early abnormalities of AIx@75 and vascular parameters suggest that patients with PNS, even in stable condition, present subclinical indicators for the development of cardiovascular disease.

P144 Augmentation Index is not a Reliable Measure of Wave Reflections in Patients with Severe Aortic Stenosis

BackgroundAugmentation index (AIx) serves as an independent predictor of cardiovascular events and mortality. It is often clinically used as a measure of arterial stiffness and reflections, a practice that was recently challenged. In this work, we sought to investigate the association between AIx and wave reflections in patients with severe aortic stenosis.MethodsThe final cohort comprised of 18 subjects (86 ± 4 years, 28% males) with severe aortic stenosis who underwent a Transcatheter Aortic Valve Implantation (TAVI). Invasive aortic and left ventricular pressure waveforms were obtained simultaneously before and after the TAVI. Key pressure waveform features were extracted and wave separation analysis was performed by combining aortic pressure and flow (Doppler echocardiography) data before and after the valve replacement.ResultsAfter the TAVI, aortic SBP and maximal blood flow velocity increased (from 134 ± 22 to 151 ± 30 mmHg, p = 0.04 and from 298 ± 65 to 376 ± 81 mL/sec, p < 0.01 respectively), while the ejection duration decreased (from 0.42 ± 0.07 to 0.35 ± 0.06 sec, p < 0.01). A significant decrease in AIx and augmented pressure was noted (from 44 ± 16 to 17 ± 12% and from 34 ± 13 to 17 ± 14 mmHg respectively, p < 0.01 for all). Wave separation analysis however showed a comparable increase in both forward (from 61 ± 14 to 79 ± 22 mmHg, p < 0.01) and backward (from 31 ± 11 to 39 ± 12 mmHg, p < 0.05) wave amplitudes. Reflection magnitude and backward wave transit time remained unchanged (p = NS).ConclusionDecrease in AIx after TAVI is not associated with changes in wave reflection amplitude or timing. For patients with severe aortic stenosis, interpretation of AIx should be done with caution.

Free-weight versus weight machine resistance exercise on pulse wave reflection and aortic stiffness in resistance-trained individuals

ABSTRACT The purpose of this study was to compare the vascular responses to acute free-weight (FW) resistance exercise (RE) versus weight machines (WM). Thirty-two resistance-trained individuals participated in this study. Both modalities involved performing acute RE and a control. Blood pressure and measures of pulse wave reflection were assessed using pulse wave analysis. Aortic stiffness was assessed using carotid–femoral pulse wave velocity (cf-PWV). A repeated measures analysis of variance was used to determine the effects of modality (FW and WM) and condition (acute RE and control) across time (rest and 10-20 min after exercise) on measures of pulse wave reflection and aortic stiffness. Significance was set a priori at p ≤ 0.05. There were no modality by condition by time interactions for any variable, such that the FW and WM modalities responded similarly across time after acute RE (p > 0.05). There were significant (p ≤ 0.05) increases in heart rate, aortic systolic blood pressure, aortic pulse pressure, augmentation index normalized at 75bpm, and decreases in subendocardial viability ratio (SEVR) after acute RE, compared to rest. There was also a significant (p ≤ 0.05) increase in cf-PWV after acute RE, compared to rest. In conclusion, this study demonstrates that acute free-weight and weight-machine RE are associated with transient increases in measures of pulse wave reflection and aortic stiffness, with reductions in myocardial perfusion. These data demonstrate that both modalities result in significant stress on the myocardium during recovery, while simultaneously increasing pressure on the aorta for at least 10–20 min.

P6506Circulating microparticles preceding endothelial dysfunction and inflammatory process in patients with pseudoexfoliative glaucoma

Abstract Background Pseudoexfoliative glaucoma (PEX) is a type of glaucoma characterized by the secretion of a grey-white, fibrogranular material in several tissues. Microparticles are shed membrane vesicles released from a variety of cell types in response to cellular activation or apoptosis and correlate with the pathogenesis of cardiovascular diseases. Endothelial MPs may be used as biomarkers of endothelial function. Purpose To evaluated the role of endothelial dysfunction, arterial stiffness and systemic inflammation in patients with PEX compared to patients with Primary open angle glaucoma (POAG) and control subjects as well as the possible pathophysiologic role of a specific microparticle profile associated with endothelial damage. Methods We enrolled 29 subjects with PEX, 57 subjects with POAG and 44 control subjects. Endothelial function was evaluated by flow-mediated dilation (FMD). Pulse wave velocity (PWV) was measured as an index of aortic stiffness and augmentation index (AIx) as a measure of arterial wave reflections. Growth differentiation factor-15 (GDF-15) and intercellular adhesion molecule1 (ICAM1) were measured to evaluate systemic inflammatory status. Total circulating MPs and EMPs were isolated and analysed by flow cytometry, utilizing specific labels for EMPs (CD 144+) and Annexin V staining for phospatidylserine bearing-MPs (AnnexinV + MPs). Results There was a linear impairment in FMD (p=0.005), PWV (p=0.007) and Aix (p=0.02) and a stepwise increase in GDF-15 (p=0.001) and sICAM-1 levels (p=0.08) between the three study groups (control, POAG, PEX). Interestingly, the PEX subjects expressed greater levels of total circulating MPs (Annexin V+) [1698 (1199–5894) MPs/μL vs. 1641 (1470–2705) MPs/μL. vs 493 (417–1512) MPs/μL, p=0.004] and EMPs (CD144+)[1412 (645–1760) MPs/μL3 vs 1380 (498–2496) MPs/μL vs 34 (184–870) MPs/μL, p&lt;0.001] compared to POAG and control subjects. Conclusion Pseudoexfoliative glaucoma is associated with impaired endothelial function, arterial wall properties and vascular inflammation with a parallel increase in EMPs. Our findings indicate the significant role of endothelial damage in the progress of glaucomatous disease especially in subjects with pseudoexfoliative glaucoma.

High-frequency ultrasound for diagnosing skin cancer in adults.

Early, accurate detection of all skin cancer types is essential to guide appropriate management and to improve morbidity and survival. Melanoma and squamous cell carcinoma (SCC) are high-risk skin cancers with the potential to metastasise and ultimately lead to death, whereas basal cell carcinoma (BCC) is usually localised, with potential to infiltrate and damage surrounding tissue. Anxiety around missing early curable cases needs to be balanced against inappropriate referral and unnecessary excision of benign lesions. Ultrasound is a non-invasive imaging technique that relies on the measurement of sound wave reflections from the tissues of the body. At lower frequencies, the deeper structures of the body such as the internal organs can be visualised, while high-frequency ultrasound (HFUS) with transducer frequencies of 20 MHz or more has a much lower depth of tissue penetration but produces a higher resolution image of tissues and structures closer to the skin surface. Used in conjunction with clinical and/or dermoscopic examination of suspected skin cancer, HFUS may offer additional diagnostic information compared to other technologies. To assess the diagnostic accuracy of HFUS to assist in the diagnosis of a) cutaneous invasive melanoma and atypical intraepidermal melanocytic variants, b) cutaneous squamous cell carcinoma (cSCC), and c) basal cell carcinoma (BCC) in adults. We undertook a comprehensive search of the following databases from inception up to August 2016: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL; CPCI; Zetoc; Science Citation Index; US National Institutes of Health Ongoing Trials Register; NIHR Clinical Research Network Portfolio Database; and the World Health Organization International Clinical Trials Registry Platform. We studied reference lists as well as published systematic review articles. Studies evaluating HFUS (20 MHz or more) in adults with lesions suspicious for melanoma, cSCC or BCC versus a reference standard of histological confirmation or clinical follow-up. Two review authors independently extracted all data using a standardised data extraction and quality assessment form (based on QUADAS-2). Due to scarcity of data and the poor quality of studies, we did not undertake a meta-analysis for this review. For illustrative purposes, we plot estimates of sensitivity and specificity on coupled forest plots. We included six studies, providing 29 datasets: 20 for diagnosis of melanoma (1125 lesions and 242 melanomas) and 9 for diagnosis of BCC (993 lesions and 119 BCCs). We did not identify any data relating to the diagnosis of cSCC.Studies were generally poorly reported, limiting judgements of methodological quality. Half the studies did not set out to establish test accuracy, and all should be considered preliminary evaluations of the potential usefulness of HFUS. There were particularly high concerns for applicability of findings due to selective study populations and data-driven thresholds for test positivity. Studies reporting qualitative assessments of HFUS images excluded up to 22% of lesions (including some melanomas) due to lack of visualisation in the test.Derived sensitivities for qualitative HFUS characteristics were at least 83% (95% CI 75% to 90%) for the detection of melanoma; the combination of three features (lesions appearing hypoechoic, homogenous and well defined) demonstrating 100% sensitivity in two studies (lower limits of the 95% CIs were 94% and 82%), with variable corresponding specificities of 33% (95% CI 20% to 48%) and 73% (95% CI 57% to 85%), respectively. Quantitative measurement of HFUS outputs in two studies enabled decision thresholds to be set to achieve 100% sensitivity; specificities were 93% (95% CI 77% to 99%) and 65% (95% CI 51% to 76%). It was not possible to make summary statements regarding HFUS accuracy for the diagnosis of BCC due to highly variable sensitivities and specificities. Insufficient data are available on the potential value of HFUS in the diagnosis of melanoma or BCC. Given the between-study heterogeneity, unclear to low methodological quality and limited volume of evidence, we cannot draw any implications for practice. The main value of the preliminary studies included may be in providing guidance on the possible components of new diagnostic rules for diagnosis of melanoma or BCC using HFUS that will require future evaluation. A prospective evaluation of HFUS added to visual inspection and dermoscopy alone in a standard healthcare setting, with a clearly defined and representative population of participants, would be required for a full and proper evaluation of accuracy.

Reduction in augmentation pressure is associated with improvement of early ventricular ejection after aortic valve replacement

BackgroundPreviously regarded as a measure of pressure wave reflection, central augmentation pressure (AP) may be influenced by the pattern of early ventricular ejection. We examined the relationship of AP to first-phase ejection fraction (EF1), a measure of ventricular ejection up to the time of the first systolic peak in central pressure in patients with aortic stenosis (AS) before and after aortic valve replacement (AVR).MethodsCarotid pressure, obtained by tonometry calibrated from peripheral mean and diastolic blood pressure, was used to calculate augmentation pressure (difference between the second and first systolic peaks of the aortic waveform). LV volume was obtained by echocardiography. EF1 was defined as the fraction of LV volume ejected from the start of systole to the time of the first systolic peak (T1) on the carotid pressure waveform. Aortic arch to abdominal aorta pulse wave velocity (aPWV) was measured by pulsed wave Doppler.Results10 patients with severe AS (aged 75.8 ± 7.8 years) and preserved EF (62.2 ± 7.1%) were studied before and 48–72 hours after AVR. There was a significant reduction in mean arterial pressure (MAP) (pre:96.9 ± 12.3 mmHg vs post:83.4 ± 11.2 mmHg, p = 0.012) and AP (pre:20.8 ± 11.4 mmHg vs post:11.0 ± 5.8 mmHg, p = 0.017). EF1 improved significantly (pre:18.7 ± 6.8% vs post:28.9 ± 12.4%, p = 0.043), whilst EF did not change. aPWV didn’t change significantly after AVR. The change in EF1 was negatively associated with change in AP (β = −0.841, p = 0.002) (Figure 1). This relationship persisted after adjustment of age, gender, BMI, baseline MAP and aortic valve area (β = −1.095, p = 0.033).ConclusionIn patients with AS and preserved EF, an improvement of early ejection is associated with reduction in augmentation pressure after AVR.Figure 1Central aortic pressure waveforms in one subject pre (blue line) and post (red line) AVR. Augmentation pressure reduced from 16mmHg to 4mmHg, whilst EF1 increased from 17.7% to 37.7% after AVR

Analysis and comparison of ion-acoustic wave reflection using laser-induced fluorescence and Langmuir probes

The first laser-induced fluorescence measurements of ion acoustic wave reflection are presented. The experiment is performed in a multi-pole cylindrical chamber using a singly ionized argon (ArII) plasma produced by means of a hot cathode. Ion-acoustic waves are launched from a mesh antenna and reflected/absorbed by a biased, solid boundary (electrode). A comparison between the Langmuir probe and laser-induced fluorescence diagnostics is presented, with complementary Electric-field probe measurements.

Preferential vascular effects of amlodipine in reducing stiffness in muscular not elastic arteries in essential hypertension & the metabolic syndrome

Introduction Arterial stiffness and wave reflection are independent prognosticators of cardiovascular morbidity and mortality. There are two types off arteries in the body; elastic and muscular. The elastic arteries receive the blood directly from the heart while the muscular arteries distribute the blood to various organs of the body. The elasticity of the major arteries decreases with age and therefore may play a key role in the development and control of hypertension and subsequently the choice of drug therapy. The aim of the study is to evaluate the effects of the amlodipine, on arterial stiffness in essential hypertension, compared to hydrochlorothiazide. Methodology We randomised 24 hypertensive patients hypertension (clinic blood pressure (BP) > 140/90 mmHg and ambulatory >135/85 mmHg) to amlodipine 5 mg or hydrochlorothiazide 12.5 mgs in a single blind parallel group study for one month and measured aortic pulse wave velocity (PWV) and augmentation index (AIx) at baseline and one month after treatment. The patients were studied fasting, having abstained from smoking, caffeinated beverages and alcohol 12 h prior to the measurements. Brachial BP and heart rate (Omron), pulse wave velocity (PWV, Complior) and augmentation index (AIx, SphymoCor), a measure of wave reflection, were measured in the supine position after a rest of 15 min. Results were analysed with JMP (SAS for Windows) using Wilcoxon-Rank Sums test and ANOVA. Results are expressed as mean ± SEM, p Results Both drugs produced a similar reduction in brachial BP but there was a greater reduction in the aortic systolic BP (20 ± 3 vs 7 ± 2 mmHg, p Conclusion This short-term study suggests that the effects of amlodipine on arterial stiffness are primarily on muscular rather than elastic arteries. This should be kept in mind when choosing the HTN treatment in elderly and those with diseases affecting the aorta.

Acute Effect of Hookah Smoking on Arterial Stiffness and Wave Reflections in Adults Aged 18 to 34 Years of Age

Hookah (waterpipe) smoking is rapidly increasing in popularity worldwide. Despite being heavily advertised in the media as a healthier alternative to cigarettes, the toxicology of hookah smoke suggest otherwise. Cigarette smoking unequivocally causes an acute increase in arterial stiffness, but whether hookah does the same is unknown. In 48 young healthy habitual hookah but not cigarette smokers, we measured heart rate, peripheral and central blood pressure, carotid-femoral pulse wave velocity (measure of arterial stiffness), aortic augmentation index (measure of wave reflection), plasma nicotine, and exhaled carbon monoxide before and after ad lib hookah smoking. Hookah smoking increased heart rate by +16 ± 1 beats/min and mean brachial arterial pressure by +6 ± 1 mm Hg (both p <0.05, mean ± SE). Most importantly, it increased carotid-femoral pulse wave velocity and aortic augmentation index by +0.66 ± 0.09 m/s-1 and +8.76 ± 3.99%, respectively (p <0.05, mean ± SE), denoting increased acute arterial stiffness. These vascular effects were accompanied by increases in plasma nicotine concentration (+5.8 ± 1.2 ng/ml, p <0.05) and expired carbon monoxide (+25.44 ± 1.68 ppm, p <0.05). All these parameters were unchanged during time-control studies (n = 14). Thus, in contrast to effective media marketing of hookah as a safer alternative to cigarettes, the present study shows for the first time that in young adult hookah smokers, a single hookah smoking session causes an acute increase in arterial stiffness of comparable magnitude to what has been previously reported for cigarettes. Further research is warranted to determine whether habitual hookah smoking accelerates the age-dependent development of hypertension and its cardiovascular complications.

Association between arterial stiffness and wave reflection with subsequent development of placental-mediated diseases during pregnancy: findings of a systematic review and meta-analysis.

We present a comprehensive systematic review of published literature to examine, whether arterial stiffness and wave reflection measurements during pregnancy differed between healthy patients and patients with placental-mediated diseases including preeclampsia (PET), small for gestational age (SGA), fetal death, and placental abruption, and a quantitative assessment of the findings using the meta-analysis approach. We searched Medline, Embase, and The Cochrane Library for studies of arterial stiffness in pregnancy, analyzed pregnancy outcomes and conducted the meta-analysis of data evaluated by trimesters of pregnancy. Hemodynamic parameters evaluated included: pulse wave velocity (PWV), augmentation index (AIx), and augmentation index-75 (AIx-75). We screened 2806 citations, reviewed 36 studies and included nine (n = 15 923) studies for further quantitative assessment. Compared with healthy pregnancy, measures of arterial stiffness and wave reflection were consistently increased among pregnant women who subsequently developed PET during all trimesters. In the first trimester, mean AIx-75 (%) in the PET group was significantly higher with estimated standardized mean difference (SMD) of 0.90 [95% confidence intervals (95% CI) 0.07-1.73; P = 0.034]. In the second trimester, the PET group had significantly higher PWV (m/s) with estimated SMD of 1.26 (95% CI 0.22-2.30; P = 0.018). Concerning the SGA group, mean AIx (%) was greater during the second trimester only: 65.5 (SD 15.6) vs. 57.0 (11.2), P < 0.01. There is significant increase in arterial stiffness and wave reflection parameters among pregnant women who subsequently developed PET and SGA fetuses. Larger studies with consistent methodological designs are required to evaluate the role and usefulness of arterial stiffness and wave reflection measurements as a screening tool for placental-mediated diseases during pregnancy.

Free-Weight Resistance Exercise Versus Weight Machines on Pulse Wave Reflection

Acute resistance exercise (ARE) has a large effect on pulse wave reflection, but the data are limited when examining these responses after free-weight (FW) versus weight-machine (WM) exercises. PURPOSE: To evaluate alterations in pulse wave reflection after FW exercise compared to WM exercise in resistance-trained individuals. METHODS: Individuals volunteered to participate in either FW (n=25) or WM (n=16) resistance exercises. Data were collected at rest, and 10-15min after ARE. The FW group completed 3 sets of 10 repetitions at 75% 1-repetition maximum (1RM) on the squat, bench press and deadlift, while the WM group completed 3 sets of 10 repetitions at 75%1RM on the leg press, lat pulldown, leg extension, chest press, and the leg curl. A 2x2x2 analysis of covariance (ANCOVA) was used to analyze the effects of group (FW, WM) across condition (ARE, control) and time (rest, recovery) with workload as a covariate. RESULTS: The groups were similar for anthropometrics (p>0.05), but differed in years spent training (FW: 7±4 yrs; WM: 4±2 yrs, p=0.0001). There were no differences at rest for any measures of pulse wave reflection. Neither group nor condition had an effect on brachial or aortic blood pressure. There was a significant 3-way interaction for heart rate (FW: rest: 59±8bpm, recovery: 88±13bpm; WM: rest: 65±9bpm, recovery: 89±13bpm, p=0.04) such that it was augmented during recovery from resistance exercise in the FW group compared to the WM group. There were also significant 3-way interactions for the augmentation index (FW: rest: 116±8.4%, recovery:121.2±9.5%; WM: rest: 116.8±8.4%, recovery: 113.7±5.5%, p=0.006), augmentation pressure (FW: rest: 5.0±2.9mmHg, recovery: 8.4±5.9mmHg; WM: rest: 4.3±4.0mmHg, recovery: 3.8±3.6mmHg, p=0.029), and the augmentation index normalized at 75bpm (FW: rest: 4.9±8.1%, recovery: 24.1±14.5%; WM: rest: 8.7±12.3%, recovery: 16.8±8.2%, p=0.015) such that they were increased in the FW group compared to the WM group during recovery from ARE, which differed from the control. CONCLUSION: These data demonstrate that recovery from free-weight resistance exercises has significant effects on pulse wave reflection that supersede those of weight machine resistance exercises in resistance-trained individuals, despite no differences in brachial or aortic blood pressures.

Hookah Smoking Causes an Acute Adverse Effect on Arterial Stiffness and Wave Reflections in Young Adults

Hookah (waterpipe) smoking is a centuries‐old, revived yet understudied epidemic of tobacco use. Despite being heavily advertised and glamorized in the media as a healthier alternative to cigarettes, the toxicology of hookah smoke suggest otherwise. Cigarette smoking unequivocally causes an acute increase in arterial stiffness, but whether hookah does the same is unknown. In 48 young healthy habitual hookah but not cigarette smokers, we measured heart rate, peripheral and central blood pressure, carotid‐femoral pulse wave velocity (measure of arterial stiffness), aortic augmentation index (measure of wave reflection), plasma nicotine, and exhaled carbon monoxide (CO) before and after 30 minutes of ad lib hookah smoking. Hookah smoking increased heart rate by +16 ± 1 beats/min and mean brachial arterial pressure by +6 ± 1 mmHg (both p &lt; 0.05, mean ± SE). Most importantly, it increased carotid‐femoral pulse wave velocity and aortic augmentation index by +0.66 ± 0.09 m/s−1and +8.76 ± 3.99%, respectively (p &lt;0.05, mean ± SE), denoting increased acute arterial stiffness. These vascular effects were accompanied by increases in plasma nicotine concentration (+5.8 ± 1.2 ng/ml, p&lt;0.05) and expired CO (+25.44 ± 1.68 ppm, p&lt; 0.05). All these parameters were unchanged during time‐control studies (n=14). Thus, in contrast to effective media marketing of hookah as a safer alternative to cigarettes, the present study shows for the first time that in young adult hookah smokers, a single hookah smoking session causes an acute increase in arterial stiffness of comparable magnitude to what has been previously reported for cigarettes. Further research is warranted to determine whether habitual hookah smoking accelerates the age‐dependent development of hypertension and its cardiovascular complications.Support or Funding InformationThis study was funded by the Tobacco‐Related Disease Research Program to Dr. Mary Rezk‐ Hanna (#23DT‐0102) and Dr. Ronald Victor (#22XT‐0017).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effects of Acute Antioxidant Cocktail Combined with a High Sodium Meal on Arterial Stiffness and Wave Reflection

Vascular dysfunction is a non‐traditional risk factor for cardiovascular disease (CVD). Further, increased arterial stiffness and wave reflection are considered independent predictors of CVD. High dietary sodium intake has been shown to impair vascular function through an increase in oxidative stress. Therefore, the objective of this study was to investigate the acute effects of an antioxidant cocktail combined with a high sodium meal on measures of arterial stiffness and wave reflection. Twenty‐six young healthy adults (11M, 15F; 22.8 ± 0.5 years; BMI 23.1 ± 0.4 kg/m2; systolic blood pressure 116 ± 2 mmHg, diastolic blood pressure 70 ± 1 mmHg) completed two trials separated by at least 48 hours. All subjects were fasted for 4 hours and women were tested during the early follicular phase of the menstrual cycle. Carotid‐femoral pulse wave velocity (PWV) and the synthesis of a central aortic pressure waveform (by radial artery applanation tonometry and generalized transfer function) were performed. Aortic augmentation index (AIx), an index of wave reflection, was calculated from the aortic pressure waveform. Participants ingested either two doses of an antioxidant cocktail (AO; each capsule contained 500 mg vitamin C, 300 IU vitamin E, and 300 mg alpha‐lipoic acid) or a placebo (PLA; cellulose). Dose one was consumed 30 min prior and dose two was consumed with the meal. The high sodium meal (1500 mg Na+) consisted of tomato soup with added table salt. Mean arterial pressure (MAP), AIx, and PWV were measured at baseline (BSL) and 30, 60, 90, and 120 minutes after meal consumption. Baseline measurements of AIx did not differ between the two visits (P &gt; 0.05) but decreased over time in both trials (AO: BSL: 8.0 ± 1.4%, 60 min: 2.0 ± 1.3%; PLA: BSL: 6.2 ± 1.4%, 60min: −0.8 ± 1.9%; P‐time effect &lt; 0.001). PWV was not different at baseline (AO: 5.3 ± 0.1 m/s, PLA: 5.2 ± 0.1 m/s; P &gt; 0.05) nor did it change during the two trials (P &gt; 0.05). Similarly, MAP was not different at baseline (P &gt; 0.05) and it remained unchanged during the two trials (P &gt; 0.05). In conclusion, acute consumption of a high sodium meal did not impair arterial stiffness or wave reflection in young, healthy adults.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Comparison of laboratory and ambulatory measures of central blood pressure and pulse wave reflection: hitting the target or missing the mark?

Prior studies demonstrating clinical significance of noninvasive estimates of central blood pressure (BP) and pulse wave reflection have relied primarily on discrete resting measures. The aim of this study was to compare central BP and pulse wave reflection measures sampled during a single resting laboratory visit against those obtained under ambulatory conditions. The secondary aim was to investigate the reproducibility of ambulatory central BP and pulse wave reflection measurements. Forty healthy participants (21 males; 24 ± 3 years) completed three measurements of brachial artery pulse wave analysis (Oscar 2 with SphygmoCor Inside) in the laboratory followed by 24 hours of ambulatory monitoring. Seventeen participants repeated the 24-hour ambulatory monitoring visit after at least 1 week. Ambulatory measures were divided into daytime (9 AM–9 PM), nighttime (1 AM–6 AM), and 24-hour periods. Compared with laboratory measurements, central systolic BP, augmentation pressure, and augmentation index (with and without heart rate normalization) were higher (all P < .01) during daytime and 24-hour periods but lower during the nighttime period (all P < .001). The drop in nighttime brachial systolic BP was larger than central systolic pressure (Δ −20 ± 6 vs. −15 ± 6 mm Hg; P < .0001). Repeat ambulatory measurements of central BP and pulse wave reflection displayed good-to-excellent intraclass correlation coefficients (r = 0.58–0.86; all P < .01), although measures of pulse wave reflection had higher coefficients of variation (14%–41%). The results highlight absolute differences in central BP and pulse wave reflection between discrete laboratory and ambulatory conditions. The use of ambulatory measures of central BP and pulse wave reflection warrant further investigation for clinical prognostic value.

Bipolar disorder and related mood states are not associated with endothelial function of small arteries in adults without heart disease.

Individuals with bipolar disorder are at increased risk for adverse cardiovascular disease (CVD) events. This study aimed to assess endothelial function and wave reflection, a risk factor for CVD, as measured by finger plethysmography in bipolar disorder to investigate whether CVD risk was higher in bipolar disorder and altered during acute mood episodes. We hypothesized that EndoPAT would detect a lower reactive hyperemia index (RHI) and higher augmentation index (AIX) in individuals with bipolar disorder compared with controls. Second, we predicted lower RHI and higher AIX during acute mood episodes. Reactive hyperemia index and augmentation index, measures of microvascular endothelial function and arterial pressure wave reflection respectively, were assessed using the EndoPAT 2000 device in a sample of 56 participants with a DSM-IV diagnosis of bipolar I disorder with 82 measures spanning different mood states (mania, depression, euthymia) and cross-sectionally in 26 healthy controls. RHI and AIX were not different between adults with and without bipolar disorder (mean age 40.3 vs. 41.2years; RHI: 2.04±0.67 vs. 2.05±0.51; AIX@75 (AIX adjusted for heart rate of 75): 1.4±19.7 vs. 0.8±22.4). When modeled in linear mixed models with a random intercept (to account for repeated observations of persons with bipolar disorder) and adjusting for age and sex, there were no significant differences between those with bipolar disorder and controls (p=0.89 for RHI; p=0.85 for AIX@75). Microvascular endothelial function and wave reflection estimated by finger plethysmography were unable to detect differences between adults with and without bipolar disorder or changes with mood states. Future research is necessary to identify more proximal and sensitive, yet relevant, biomarkers of abnormal mood-related influences on CVD risk or must target higher risk samples.

Superior Effects of High-Intensity Interval Training vs. Moderate Continuous Training on Arterial Stiffness in Episodic Migraine: A Randomized Controlled Trial.

Background: Migraine is associated with increased cardiovascular risk and vascular dysfunction. Since aerobic exercise can reduce cardiovascular risk, the present randomized controlled trail aimed at investigating the effects of high-intensity interval training (HIT) vs. moderate continuous exercise training (MCT) on arterial stiffness in migraine patients.Methods: Forty-eight episodic migraineurs were initially enrolled in the study. 37 patients [female: 30; age: 37 (SD: 10); BMI: 23.1 (5.2); Migraine days per month: 3.7 (2.5)] completed the intervention. Central blood pressure, pulse wave reflection, and aortic pulse wave velocity (PWV) were obtained by an oscillometric monitor. Incremental treadmill exercise testing yielded maximal and submaximal fitness parameters. Participants were randomly assigned to either HIT, MCT, or a control group (CON). The intervention groups trained twice a week over a 12-week intervention period.Results: After adjustment for between-group baseline differences, a moderate meaningful overall reduction of the augmentation index at 75 min−1 heart rate (AIx@75) was observed [partial eta squared () = 0.16; p = 0.06]. With 91% likely beneficial effects, HIT was more effective in reducing AIx@75 than MCT [HIT: pre 22.0 (9.7), post 14.9 (13.0), standardized mean difference (SMD) = 0.62; MCT: pre 16.6 (8.5), post 21.3 (10.4), SMD −0.49]. HIT induced a relevant reduction in central systolic blood pressure [cSBP: pre 118 (23) mmHg, post 110 (16) mmHg, SMD = 0.42] with a 59% possibly beneficial effect compared to CON, while MCT showed larger effects in lowering central diastolic blood pressure [pre 78 (7) mmHg, post 74 (7) mmHg, SMD = 0.61], presenting 60% possibly beneficial effects compared to CON. Central aortic PWV showed no changes in any of the three groups. Migraine days were reduced more successfully by HIT than MCT (HIT: SMD = 1.05; MCT: SMD = 0.43).Conclusion: HIT but not MCT reduces AIx@75 as a measure of pulse wave reflection and indirect marker of systemic arterial stiffness. Both exercise modalities beneficially affect central blood pressure. HIT proved to be an effective complementary treatment option to reduce vascular dysfunction and blood pressure in migraineurs.

Sex differences in aortic augmentation index in adolescents.

Augmentation index (AIx) is a noninvasive measure of pulse wave reflection. AIx is associated with cardiovascular disease. Adult women have a higher AIx than men, but the factors determining this sex-related difference remain to be determined. To examine factors associated with AIx in adolescents, participants in the Childhood Asthma Prevention Study, followed from birth, were assessed at age 14 years, with AIx standardized to a heart rate of 75/min (AIx_75) and pulse wave velocity. Associations of AIx_75 and pulse wave velocity with height, change in height, and measures of puberty were assessed. AIx_75 was higher in women compared to men [-24.5 (12.1) versus -32.3 (12.4)%; P < 0.001]. Lower AIx_75 was significantly related to greater change in height between 8 and 14 years, but not to achieved height. The sex difference in AIx was not independently related to puberty variables. Differences between sexes included early life weight gain, lipids, height, BMI-Z-score, change in height from 8 to 14 years, and age at peak height velocity. Change in AIx_75 from 8 to 14 years was highly associated with change in height (m) from 8 to 14 years (B = -88.8, 95% confidence interval -137.3 to -40.3, P = < 0.001). The difference between sexes established at 8 years was not amplified from 8 to 14 years. AIx is higher in girls than boys at 14 years and is closely associated with change in height between 8 and 14 years. Measures of puberty do not appear to independently influence the sex difference in AIx in adolescents.

Experimental analysis of wave deformation and bottom flow under wave-current interaction in the river mouth

A river mouth is a physically dynamic area. In this study, we analyze the hydrodynamic characteristics of this area by performing hydraulic experiments to investigate wave-current interaction by building a river mouth model in a 3-D wave basin. Using the results of these hydraulic experiments, we analyze the hydrodynamic characteristics of the region in which wave-current coexist in the river channel and the vicinity of the river mouth. We observe that, in a river channel, the turbulence flow field develops more rapidly when both waves and current are present as opposed to a situation where no current exists. This contributes to the wave energy loss, resulting in wave attenuation. This phenomenon is more obvious when the ratio between the current velocity and wave celerity, Vc/Ci increases. From the wave reflection measurements, we observe that the reflection coefficient increases as Vc/Ci increases. This causes wave attenuation in the wave-current interaction. We observe the changes in the wave heights, bottom flow, and horizontal velocity distributions in the areas where wave-current coexist in the river mouth. In particular, the measured horizontal velocity distribution shows the influence of the flow field on the combined effects of the wave and current velocity components. We observe that there is a close relationship between the wave-current interaction and sediment transport near the river mouth.

The relation of digital vascular function to cardiovascular risk factors in African-Americans using digital tonometry: the Jackson Heart Study

Digital vascular tone and function, as measured by peripheral arterial tonometry (PAT), are associated with cardiovascular risk and events in non-Hispanic whites. There are limited data on relations between PAT and cardiovascular risk in African-Americans. PAT was performed on a subset of Jackson Heart Study participants using a fingertip tonometry device. Resting digital vascular tone was assessed as baseline pulse amplitude. Hyperemic vascular response to 5 minutes of ischemia was expressed as the PAT ratio (hyperemic/baseline amplitude ratio). Peripheral augmentation index (AI), a measure of relative wave reflection, also was estimated. The association of baseline pulse amplitude (PA), PAT ratio, and AI to risk factors was assessed using stepwise multivariable models. The study sample consisted of 837 participants from the Jackson Heart Study (mean age, 54 ± 11 years; 61% women). In stepwise multivariable regression models, baseline pulse amplitude was related to male sex, body mass index, and diastolic blood pressure (BP), accounting for 16% of the total variability of the baseline pulse amplitude. Age, male sex, systolic BP, diastolic BP, antihypertensive medication, and prevalent cardiovascular disease contributed to 11% of the total variability of the PAT ratio. Risk factors (primarily age, sex, and heart rate) explained 47% of the total variability of the AI. We confirmed in our cohort of African-Americans, a significant relation between digital vascular tone and function measured by PAT and multiple traditional cardiovascular risk factors. Further studies are warranted to investigate the utility of these measurements in predicting clinical outcomes in African-Americans.