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Abstract High‐intensity interval exercise (HIIE) is recommended because it provides favourable haemodynamic stimulation, but excessive haemodynamic fluctuations may be an adverse impact on the brain. We tested whether the cerebral vasculature is protected against systemic blood flow fluctuation during HIIE. Fourteen healthy men (age 24 ± 2 years) underwent four 4‐min exercises at 80–90% of maximal workload (Wmax) interspaced by 3‐min active rest at 50–60% Wmax. Transcranial Doppler measured middle cerebral artery blood velocity (CBV). Systemic haemodynamics (Modelflow) and aortic pressure (AoP, general transfer function) were estimated from an invasively recorded brachial arterial pressure waveform. Using transfer function analysis, gain and phase between AoP and CBV (0.39–10.0 Hz) were calculated. Stroke volume, aortic pulse pressure and pulsatile CBV increased during exercise (time effect: P

The problem of road-related sinkhole stability has long been one of the main safety concerns to pavement engineers. Collapse and blowout failures are two typical types of pipeline-related sinkhole failures. Although much research on sinkhole stability analyses can be found in the literature, most of them assume a simple circular or rectangular shape of a cavity. In this study, the problem of sinkhole stability in an ellipsoidal cavity is investigated under both blowout and collapse conditions using advanced finite element limit analysis with adaptive meshing in an axisymmetric condition. A dimensionless pressure ratio is defined to represent sinkhole stability that is a function of many design parameters such as depth ratio, elliptical shape ratio, and soil strength ratio. Selected results are compared with published solutions, and comprehensive solutions of the parametric study are presented in the form of charts for use by design engineers. The present study contributes to the understanding of sinkhole stability under an ellipsoidal cavity, and it should be of interest to the road engineering community.

Previous studies have shown that normal and complex land walking (e.g. dual-task and obstacle walk) have a positive effect on the prefrontal cortex (PFC) and executive function. However, little is known about the benefits of aquatic walking. The underwater environment is a complex environment with water flow and resistance. Such an environment may induce different brain responses than the land environment. These responses can possibly affect brain function. Therefore, we hypothesized that aquatic walking enhances PFC and executive function more than land walking. Seven participants (age: 57.6 ± 7.0 years, body mass index: 22.9 ± 4.6 kg m−2) performed walking for 10 mins at a self-selected comfortable speed in both conditions. Then, the color-word Stroop task (CWST) was administered at pre- and post-exercises. The left prefrontal hemoglobin activity was monitored via functional near-infrared spectroscopy during the CWST and walking trial. Stroop interference performance, which reflects executive function, was calculated using reaction time and hemoglobin activity during the CWST. Compared to land walking, aquatic walking enhanced cortical activations and reaction time in the Stroop interference. In addition, aquatic walking was more likely to enhance cortical function than land walking. Hence, aquatic walking can induce higher cortical activation relative to land walking at a similar intensity, and it promotes executive function in healthy middle- and old-aged individuals.

IntroductionAerobic exercise training has been shown to improve microstructural organization of the corpus callosum (CC); however, evidence of this topographic effect is limited.PurposeTo compare the CC microstructural organization between endurance athletes and sedentary adults using a white-matter fiber tractography approach.Materials and methodsDiffusion tensor imaging (DTI) and T1-weighted structural data were collected from 15 male young endurance athletes and 16 age- and sex-matched sedentary adults. DTI data were analyzed with a global probabilistic tractography method based on neighborhood anatomical information. Fractional anisotropy (FA) and mean, radial (RD), and axial diffusivities were measured in the eight CC tracts: rostrum, genu, splenium, and body’s prefrontal, premotor, central, parietal, and temporal tracts. Cortical thickness of the CC tract endpoints and the CC tract length and volume were also measured. Physical activity level was assessed by metabolic equivalents (METs).ResultsThe athlete group had an average VO2max of 69.5 ± 3.1 ml/kg/min, which is above 90%ile according to the American College of Sports Medicine guideline. Compared with the sedentary group, the athlete group had higher FA in the CC body’s premotor and parietal tracts and the CC splenium. These tracts showed lower RD in the athlete compared with sedentary group. The voxelwise analysis confirmed that the athlete group had higher FA in the CC and other white matter regions than the sedentary group, including the corona radiata, internal capsule, and superior longitudinal fasciculus. Cortical thickness of the CC tract endpoints and the CC tract lengths and volumes were similar between the two groups. Physical activity levels were positively correlated with FA in the CC body’s parietal (r = 0.486, p = 0.006) and temporal (r = 0.425, p = 0.017) tracts and the CC splenium (r = 0.408, p = 0.023).ConclusionYoung endurance athletes have higher microstructural organization of the CC tracts connected the sensorimotor and visual cortices than the age- and sex-matched sedentary adults.

Abstract The impact of underwater exercise on respiratory function remains unclear when its metabolic rate is matched with exercise performed on land. Therefore, we compared the breathing responses and respiratory function during and after water (WC)‐ and land (LC)‐based cycling performed at the matched oxygen uptake (VO2). Twelve healthy men performed 15 min of incremental WC and LC on separate days. During WC, participants cycled continuously at 30, 45, and 60 rpm (stages 1, 2, and 3) for 5 min each. During LC, participants cycled at 60 rpm for 15 min while wattage was increased every 5 min and adjusted to match VO2 to the WC condition. Breathing patterns during cycling and spirometry data before and after cycling were collected. VO2 during WC and LC was similar. Respiratory rate (WC: 27 ± 3 vs. LC: 23 ± 4 bpm, p = 0.012) and inspiratory flow (WC: 1233 ± 173 vs. LC: 1133 ± 200 ml/s, p = 0.035) were higher and inspiratory time (WC: 1.0 ± 0.1 vs. LC: 1.2 ± 0.2 s, p = 0.025) was shorter at stage 3 during WC than LC. After WC, forced vital capacity (p = 0.010) significantly decreased while no change was observed after LC. These results suggest that at similar metabolic rates during WC and LC, breathing is slightly shallower during WC which may have chronic effects on respiratory muscle function after multiple bouts of aquatic cycling. Underwater exercise may be beneficial for respiratory muscle rehabilitation when performed on a chronic basis.

Although water-based exercise is one of the most recommended forms of physical activity, little information is available regarding its influence on cardiac workload and myocardial oxygen supply-to-demand. To address this question, we compared subendocardial viability ratio (SEVR, the ratio of myocardial oxygen supply-to-demand), cardiac inotropy (via the maximum rate of aortic pressure rise [dP/dTmax]), and stroke volume (SV, via a Modelflow method) responses between water- and land-based exercise. Eleven healthy men aged 24 ± 1 years underwent mild- to moderate-intensity cycling exercise in water (WC) and on land (LC) consecutively on separate days. In WC, cardiorespiratory variables were monitored during leg cycling exercise (30, 45, and 60 rpm of cadence for 5 min each) using an immersible stationary bicycle. In LC, each participant performed a cycling exercise at the oxygen consumption (VO2) matched to the WC. SEVR and dP/dTmax were obtained by using the pulse wave analysis from peripheral arterial pressure waveforms. With increasing exercise intensity, SEVR exhibited similar progressive reductions in WC (from 211 ± 44 to 75 ± 11%) and LC (from 215 ± 34 to 78 ± 9%) (intensity effect: P < 0.001) without their conditional differences. WC showed higher SV at rest and a smaller increase in SV than LC (environment-intensity interaction: P = 0.009). The main effect of environment on SV was significant (P = 0.002), but that of dP/dTmax was not (P = 0.155). SV was correlated with dP/dTmax (r = 0.717, P < 0.001). When analysis of covariance (ANCOVA) was performed with dP/dTmax as a covariate, the environment effect on SV was still significant (P < 0.001), although environment-intensity interaction was abolished (P = 0.543). These results suggest that water-based exercise does not elicit unfavorable myocardial oxygen supply-to-demand balance at mild-to-moderate intensity compared with land-based exercise. Rather, water-based exercise may achieve higher SV and better myocardial energy efficiency than land-based exercise, even at the same inotropic force.

Aquatic exercise is an attractive form of exercise that utilizes the various properties of water to improve physical health, including arterial stiffness. However, it is unclear whether regular head-out aquatic exercise affects aortic hemodynamics, the emerging risk factors for future cardiovascular disease. The purpose of this study was to investigate whether head-out aquatic exercise training improves aortic hemodynamics in middle-aged and elderly people. In addition, to shed light on the underlying mechanisms, we determined the contribution of change in arterial stiffness to the hypothesized changes in aortic hemodynamics. Twenty-three middle-aged and elderly subjects (62 ± 9 years) underwent a weekly aquatic exercise course for 15 weeks. Aortic hemodynamics were evaluated by pulse wave analysis via the general transfer function method. Using a polar coordinate description, companion metrics of aortic pulse pressure (PPC = √{(systolic blood pressure)2 + (diastolic blood pressure)2}) and augmentation index (AIxC = √{(augmentation pressure)2 + (pulse pressure)2}) were calculated as measures of arterial load. Brachial-ankle (baPWV, reflecting stiffness of the abdominal aorta and leg artery) and heart-ankle (haPWV, reflecting stiffness of the whole aortic and leg artery) pulse wave velocities were also measured. The rate of participation in the aquatic training program was 83.5 ± 13.0%. Aortic systolic blood pressure, pulse pressure, PPC, AIxC, baPWV, and haPWV decreased after the training (P < 0.05 for all), whereas augmentation index remained unchanged. Changes in aortic SBP were correlated with changes in haPWV (r = 0.613, P = 0.002) but not baPWV (r = 0.296, P = 0.170). These findings suggest that head-out aquatic exercise training may improve aortic hemodynamics in middle-aged and elderly people, with the particular benefits for reducing aortic SBP which is associated with proximal aortic stiffness.

Abstract Ischemic skeletal muscle conditions are known to augment exercise‐induced increases in blood pressure (BP). Aging is also a factor that enhances the pressor response to exercise. However, the effects of aging on the BP response to ischemic exercise remain unclear. We, therefore, tested the hypothesis that aging enhances the BP response to rhythmic handgrip (RHG) exercise during postexercise muscle ischemia (PEMI). We divided the normotensive participants without cardiovascular diseases into three age groups: young (n = 26; age, 18–28 years), middle‐aged (n = 23; age, 35–59 years), and older adults (n = 23; age, 60–80 years). The participants performed RHG exercise with minimal effort for 1 min after rest with and without PEMI, which was induced by inflating a cuff on the upper arm just before the isometric handgrip exercise ended; the intensity was 30% of maximal voluntary contraction force. Under PEMI, the increase in diastolic BP (DBP) from rest to RHG exercise in the older adult group (Δ13 ± 2 mmHg) was significantly higher than that in the young (Δ5 ± 2 mmHg) and middle‐aged groups (Δ6 ± 1 mmHg), despite there being no significant difference between the groups in the DBP response from rest to RHG exercise without PEMI. Importantly, based on multiple regression analysis, age remained a significant independent determinant of both the SBP and DBP responses to RHG exercise during PEMI (p

Warm water immersion (WWI) has a potentially favorable effect on vascular health. However, the effects of short-term WWI on vascular function and central hemodynamics remain unclear. The present study aimed to determine the acute effects of short-term WWI on arterial stiffness and central hemodynamics in healthy men. Ten healthy men (27–57 years, 44 ± 12 years of mean age) underwent 5-min WWI (40–41°C) at the heart level. Systemic hemodynamics and tympanic temperature were monitored during WWI. Furthermore, pulse wave velocity (PWV) and aortic hemodynamics were measured before and 10 min after WWI. Cardiac output (CO) (via the Modelflow method) increased (P = 0.037), whereas tympanic temperature did not change (P = 0.879) during WWI. After 5-min WWI, heart rate (HR) and brachial diastolic blood pressure (BP) were significantly decreased. Aortic and leg PWV were decreased by 7.5 and 3.1%, respectively (P = 0.006 and P = 0.040). Femoral arterial blood flow was increased by 45.9% (P = 0.002), and leg vascular resistance was decreased by 29.1% (P < 0.001). Regarding central hemodynamic variables (estimated by general transfer function), aortic BP and augmentation index (AIx) did not change significantly, but the subendocardial viability ratio (SEVR), an index of coronary perfusion, was increased (P = 0.049). Our results indicate that a short-term WWI acutely improves aortic and peripheral arterial stiffness and coronary perfusion. Further studies to determine the interaction between the residual effect of a single bout of short-term WWI and chronic change (e.g., adaptation) in arterial stiffness and central hemodynamics are needed.

Frequent assessment of vascular health (e.g., arterial stiffness) may predict the incidence of cardiovascular disease. The Second Derivative of the finger Photoplethysmogram Aging Index (SDPTGAI) may be used as an index of vascular aging and a screening tool for arteriosclerotic disease. To test its reliability as a measurement of arterial stiffness, we compared SDPTGAI with aortic Augmentation Index (AIx) at rest and during short-term mental stress (study 1). In addition, the day-to-day variability of SDPTGAI was evaluated (study 2). In study 1, a total of 31 apparently healthy adults were measured with the photoplethysmogram on the right index finger in the sitting resting condition. Simultaneously, the applanation tonometry was used to record blood pressure waveforms from the left radial artery (for aortic pressure waveform estimation via a general transfer function). Subsequently, 22 subjects underwent a 30-s arithmetic test (double-digit subtraction). In study 2, 10 young adults were measured with SDPTGAI for five consecutive days. In study 1, we found that SDPTGAI was significantly correlated with AIx (r = 0.682, p < 0.001). During the arithmetic task, heart rate and SDPTGAI were significantly increased from the baseline values (p < 0.05 for both) whereas AIx remained to be unchanged. In study 2, SDPTGAI showed 12.0 ± 9.9% of Coefficient of Variation (CV) across all subjects, which is comparable to CV of heart rate (12.5 ± 5.4%). These findings suggest that SDPTGAI has the potential for evaluating arterial stiffness and wave reflection at the resting condition, but it needs to be measured under well-rested relaxed condition because the finger photoplethysmogram may easily be affected by mental stressor.

Homebased exercise is often advocated to improve physical fitness in the aging population, especially when outdoor activity is not available. Yet we often have a limited understanding of its training effects for clinical uses. Aim: To investigate a short-term exercise training of standing core exercise on femoral blood flow and vascular hemodynamic changes in middle-aged to the older population. Methods: A total of 34 middle-aged to older adults were recruited and randomly assigned into walking (M/F = 6/7, age = 66 ± 3 years), core exercise (M/F = 6/6, age = 66 ± 2 years), and the control group (M/F = 4/5, age = 70 ± 3 years). Carotid and brachial blood pressure, Carotid-femoral Pulse Wave Velocity (PWV) and Brachial-ankle PWV (baPWV), femoral blood flow and compliance, leg hemodynamics, as well as aerobic and muscular fitness (30 s arm curl and sit-to-stand test) were measured pre and post 8 weeks of exercise training (60–70% HRmax, three sessions/week). Results: Core exercise group significantly increased femoral blood flow, but not overall vascular functions; arm muscle endurance and leg power performance were also significantly improved after training. The walking group significantly reduced baPWV, leg resistance, as well as increase femoral blood flow and compliance after training. Compared with the control, the core group elicited a higher femoral blood blow, whereas leg resistance was significantly reduced in the walking group after training. Conclusion: A short-term standing core training appears to augment femoral blood flow and muscular fitness in middle-aged to older adults, yet walking is more effective in improving overall vascular health in this population. •Standing core training improves femoral blood flow in middle-aged to older adults. •The increase of blood velocity appears to associate with the improvement of blood flow. •Walking exercise training is superior to improve overall vascular function.

Background: Exercise training-induced adaptation of central Blood Pressure (BP) depends on exercise mode. Kendo, a traditional Japanese martial art, is a unique exercise mode because its training encompasses anaerobic and resistance training components. However, the effects of habitual kendo training on central BP have not been established. Objective: The aim of this study was to compare the central BP of high-level kendo athletes and age-matched controls without exercise habits. Methods: Thirty-six young university kendo athletes (the kendo athlete group) and 29 young sedentary individuals (the control group) participated in this cross-sectional study. Central hemodynamics were estimated from carotid arterial waveforms via a generalized transfer function. Stroke volume was computed from brachial arterial waveforms using the Modelflow method. Results: Central systolic BP and Central Pulse Pressure (cPP) were higher in the kendo athlete group than in the control group (both, p < 0.01). Central diastolic BP did not differ between the two groups. Stroke Volume Index (SVI; stroke volume adjusted for body surface area) and the maximum rate of aortic pressure rise during systole (dP/dTmax), which reflects left ventricle contractility, were significantly higher in the kendo athlete group than in the control group (p < 0.05), and these parameters showed a significant positive correlation with cPP (SVI: r = 0.34, p < 0.01; dP/dTmax: r = 0.79, p < 0.01). Conclusion: These results suggest that habitual kendo training may increase central pulse pressure through increases in left ventricular systolic function. •Kendo is ideal for investigating of training adaptation since it induces the characteristics of anaerobic exercise training and resistance training; that is, kendo athletes had both high anaerobic capacity and high muscle strength compared with sedentary controls. •In the present study, central blood pressure (central systolic blood pressure and central pulse pressure) was significantly higher in the kendo athlete group than in the control group. •Stroke Volume Index (SVI; stroke volume adjusted for body surface area) and the maximum rate of aortic pressure rise during systole (dP/dTmax) but not augmented pressure in the kendo athlete group were also significantly higher than those in the control group. •In addition, SVI and dP/dTmax showed a significant positive correlation with central pulse pressure. •These results suggest that combined anaerobic exercise and muscular strength training may increase central blood pressure through increases in left ventricular systolic function.

Background: Sleep apnea is known as a high-risk factor for cardiovascular disease (CVD); However, the influence of apnea on aortic blood pressure and augmentation index (AIx), which cardiac load and independent risks for a future CVD event, remains unclear. Therefore, this study aimed to examine the influence of intermittent normoxic apnea on aortic arterial hemodynamics in healthy men. Methods: Sixteen healthy young men (23 ± 1.6 years mean ± SD) underwent the repetitive 20-s apnea with a 40 s interval for 20 min. During the interval, each subject maintained a breath pace at 15 breaths/min. Central hemodynamics were evaluated every 5 min by pulse wave analysis from peripheral (radial) arterial pressure waveforms via general transfer function method and compared among three phases defined as “breath” (for 20 s before apnea), “apnea”, and “rebreathe” (for 20 s after apnea). The baseline values were calculated from the first breathing cycle and compared with each breathing phase every 5 min. Results: Aortic systolic blood pressure and AIx were significantly higher at rebreathe phase than the other phases. Likewise, heart rate and double product (aortic systolic blood pressure × heart rate) were significantly higher in rebreathe phase than the other phases. Conclusions: These results suggest that cardiac load is increased by intermittent normoxic apnea, especially during the rebreathing phase.

Background: Daily assessment of vascular health may predict cardiovascular incidence. Vascular aging index (VAI) calculated from second derivative of photoplethysmogram (SDPTG) is a simple, non-invasive measure possibly reflecting vascular stiffness. However, the effects of daily life events such as mental stress and day-to-day variability as well as its relation to other indices of vascular stiffness remain unclear. Purpose: To determine whether VAI measured by finger SDPTG is 1) correlated with peripheral augmentation index (pAI), 2) altered by acute mental stress, and 3) affected by day-to-day variability. Methods: Simultaneous measurements of finger photoplethysmogram and radial artery tonometry were performed in 68 healthy subjects (age = 22–64 years) of whom 31 subjects were further tested during a 30-second mental arithmetic and 10 subjects underwent day-to-day variability assessment for 5 consecutive days. VAI was calculated from a 20-second segment of photoplethysmogram data [1]. Results: At rest, VAI was positively correlated with pAI (r = 0.62, p < 0.001). During mental arithmetic, VAI increased when compared with the control condition (p = 0.032) whereas pAI did not show significant change. Five day measurements of VAI demonstrated the overall coefficient of variation of 21.1 ± 13.7% across all subjects. Conclusion: VAI calculated from the finger SDPTG is related to a measure of vascular stiffness and sensitive to mental stress with fair day-to-day variability. These findings suggest that VAI assessment needs to be performed at the quiet resting condition.

Retrograde and oscillatory shear can induce profound pro-atherogenic effects on endothelial cells, and increase with advancing age in peripheral conduit arteries. Habitual aerobic exercise ameliorates conduit artery retrograde and oscillatory shear in middle-aged and older adults; however, the mechanisms underlying the change in conduit artery shear rate patterns caused by habitual aerobic exercise remains unclear. This study investigated the role of sympathetic vasoconstrictor tone in the habitual aerobic exercise-induced change in conduit artery shear in middle-aged and older adults. Fifteen healthy middle-aged and older adults (aged 52-67 years; 4 men, 11 women) were divided into physically-active and sedentary control groups, based on reported exercise history. We measured brachial artery shear rate patterns at rest and during sympathetic nerve activity stimulation (via lower body negative pressure [LBNP] at -20 mmHg). At rest, the physically-active group showed smaller brachial artery retrograde and oscillatory shear compared to a sedentary control group (p < 0.05). The levels of brachial retrograde and oscillatory shear were elevated by the LBNP stimulation in the physically active group (p < 0.05), but not in the sedentary control group. Our results suggest that the attenuated basal sympathetic vasoconstrictor tone may contribute to the habitual aerobic exercise-induced decreases in conduit artery retrograde and oscillatory shear at rest in middle-aged and older adults.

The augmented cerebral hemodynamic pulsatility could lead to the elevated risk of cerebrovascular disease. To determine the impact of an acute orthostatic challenge on a pulsatile component of cerebral hemodynamics, mild lower body negative pressure (LBNP, -30 mmHg) was applied to 29 men. Middle cerebral artery blood flow velocity (MCAv) was measured by transcranial Doppler technique. Stroke volume (SV) was estimated by the Modelflow method with adjustment by the Doppler ultrasound-measured SV at rest. SV, peak and pulsatile MCAv, and pulsatility index were significantly lower during the LBNP stimulation than those at the baseline (e.g., supine resting) (P < 0.05 for all), whereas mean arterial pressure and mean MCAv remained unchanged. The change in SV with the LBNP stimulation significantly correlated with corresponding changes in peak and pulsatile MCAv (r = 0.617, P < 0.001; r = 0.413, P = 0.026, respectively). These results suggest that pulsatile components of cerebrovascular hemodynamics are dampened during the transient period of orthostatic challenge (as simulated using LBNP) when compared to supine rest, and which is partly due to the modified SV.

Tertiary breast reconstruction after a failed autologous procedure is often performed under various restrictions, posing considerable problems not only in the choice of alternative free flap but also in that of recipient vessels. This is a case report of a free contralateral latissimus dorsi myocutaneous flap combined with a silicone gel implant, with flap pedicle anastomosis to the contralateral internal mammary recipient vessels in a 46-year-old woman with right breast deformity. She underwent a right modified radical mastectomy and failed attempts of reconstruction at another hospital. The deep inferior epigastric artery perforator flap had already been harvested for the failed reconstruction and high-level interruptions of the internal mammary, thoracodorsal, and thoracoacromial vessels were revealed on preoperative three-dimensional computed tomography angiography; therefore, we selected a contralateral latissimus dorsi myocutaneous flap to supply the lower pole skin along with a silicone gel implant for volume in this tertiary breast reconstruction. However, weak blood flow in the ipsilateral internal mammary artery and exhaustion of all recipient ipsilateral vessels in previous attempts to salvage the failing deep inferior epigastric artery perforator flap necessitated the use of the contralateral internal mammary recipient vessels. A contralateral latissimus dorsi myocutaneous flap with contralateral internal mammary recipient vessel anastomosis appears to be a viable option in complicated cases with unavailable deep inferior epigastric artery perforator flap or ipsilateral recipient vessels.

To investigate the influence of short-term vigorous endurance training on aortic blood pressure (BP), pulse wave analysis was performed in 36 highly trained elite collegiate endurance runners before and after a 7-day intense training camp. Subjects participated three training sessions per day, which mainly consisted of long distance running and sprint training to reach the daily target distance of 26 km. After the camp, they were divided into two groups based on whether the target training was achieved. Aortic systolic BP, pulse pressure, and tension-time index (TTI, a surrogate index of the myocardial oxygen demand) were significantly elevated after the camp in the accomplished group but not in the unaccomplished group, whereas the brachial BP remained unchanged in both groups. The average daily training distance was significantly correlated with the changes in aortic systolic BP (r = 0.608, p = 0.0002), pulse pressure (r = 0.415, p = 0.016), and TTI (r = 0.438, p = 0.011). These results suggest that aortic BP is affected by a short-term vigorous training camp even in highly trained elite endurance athletes presumably due to a greater training volume compared to usual.

Background: The determinants responsible for increasing central pressure augmentation, a strong risk factor for cardiovascular disease, remain highly controversial. The aim of this study was to determine the contribution of the impedance mismatch between central and leg arteries on central pressure augmentation. Thus, we investigated whether central pressure augmentation is influenced by manipulation of central-to-leg arterial stiffness mismatch by an acute leg heating. Methods: Nineteen postmenopausal women underwent the warmth stimulation on both lower legs (20 min of exposure to far infra-red radiation at 43–45 °C followed by retaining warmth by a blanket for 30 min). Central (aortic) hemodynamic measures were obtained from applanation tonometrically-radial arterial pressure waveforms via the validated general transfer function. Results: The leg heating decreased only the leg pulse wave velocity. And thus, the central-to-leg arterial stiffness was changed from positive to negative; however, any central (aortic) hemodynamic measures including reflected wave amplitude, aortic blood pressure, and augmentation index, were not changed significantly. Conclusions: Our results suggest that the acute bout of leg heating induces the less of central-to-leg arterial stiffness mismatch but not influence central pressure augmentation in postmenopausal women.

Aorta effectively buffers cardiac pulsatile fluctuation generated from the left ventricular (LV) which could be a mechanical force to high blood flow and low-resistance end-organs such as the brain. A dynamic orthostatic challenge may evoke substantial cardiac pulsatile fluctuation via the transient increases in venous return and stroke volume (SV). Particularly, this response may be greater in endurance-trained athletes (ET) who exhibit LV eccentric remodeling. The aim of this study was to determine the contribution of aortic compliance to the response of cerebral blood flow fluctuation to dynamic orthostatic challenge in ET and age-matched sedentary (SED) young healthy men. ET (n = 10) and SED (n = 10) underwent lower body negative pressure (LBNP) (−30 mmHg for 4 min) stimulation and release the pressure that initiates a rapid regain of limited venous return and consequent increase in SV. The recovery responses of central and middle cerebral arterial (MCA) hemodynamics from the release of LBNP (~15 s) were evaluated. SV (via Modeflow method) and pulsatile and systolic MCA (via transcranial Doppler) normalized by mean MCA velocity (MCAv) significantly increased after the cessation of LBNP in both groups. ET exhibited the higher ratio of SV to aortic pulse pressure (SV/AoPP), an index of aortic compliance, at the baseline compared with SED (P < 0.01). Following the LBNP release, SV was significantly increased in SED by 14 ± 7% (mean ± SD) and more in ET by 30 ± 15%; nevertheless, normalized pulsatile, systolic, and diastolic MCAv remained constant in both groups. These results might be attributed to the concomitant with the increase in aortic compliance assessed by SV/AoPP. Importantly, the increase in SV/AoPP following the LBNP release was greater in ET than in SED (P < 0.01), and significantly correlated with the baseline SV/AoPP (r = 0.636, P < 0.01). These results suggest that the aortic compliance in the endurance athletes is able to accommodate the additional SV and buffer the potential increase in pulsatility at end-organs such as the brain.

This procedure was developed for preservation of the rectus muscle components and deep inferior epigastric vessel after deep inferior epigastric perforator (DIEP) flap harvesting. A 53-year-old woman with granuloma caused by silicone injection underwent bilateral nipple-sparing mastectomies and immediate reconstruction with "mini-flow-through" DIEP flaps. The flaps were dissected based on the single largest perforator with a short segment of the lateral branch of the deep inferior epigastric vessel that was transected as a free flap for breast reconstruction. The short segments of the donor deep inferior epigastric vessel branch are primarily end-to-end anastomosed to each other. A short T-shaped pedicle mini-flow-through DIEP flap is interposed in the incised recipient's internal mammary vessels with two arterial and four concomitant venous anastomoses. Although it requires multiple vascular anastomoses and a short pedicle for the flap setting, the mini-flow-through DIEP flap provides a large pedicle caliber, enabling safer microsurgical anastomosis and well-vascularized tissue for creating a natural breast without consuming time or compromising the rectus muscle components and vascular flow of both the deep inferior epigastric and internal mammary vessels.

Background: Reduction in arterial compliance with aging increases the risk of cardiovascular disease. Lifestyle modification, particularly aerobic exercise and dietary modification, has a favorable effect on vascular aging. Curcumin, a major component of turmeric, is an anti-inflammatory agent. Therefore, it is plausible to hypothesize that curcumin improves arterial compliance. We investigated the effects of curcumin ingestion alone and in combination with aerobic exercise training on arterial compliance in postmenopausal women. Methods: A total of 51 postmenopausal women were assigned to 4 groups: placebo, curcumin, exercise and placebo (Ex + placebo), and exercise and curcumin (Ex + curcumin). Curcumin or placebo was ingested orally for 8 weeks. The exercise groups underwent moderate aerobic exercise training for 8 weeks. Results: Carotid arterial compliance increased significantly in the curcumin, Ex + placebo, and Ex + curcumin groups, whereas no such changes were observed in the placebo control group. The magnitude of increases in carotid arterial compliance was the greatest in the Ex + curcumin group. Conclusion: We concluded that curcumin ingestion improves carotid arterial compliance and that the combination of curcumin and aerobic exercise training was more efficacious in increasing central arterial compliance than either of these treatments alone in postmenopausal women.

Background: Age-related decrease in cerebral blood flow is a risk factor for cognitive decline. Aerobic exercise training improves vascular and cognitive functions. However, the effect of exercise training on age-related reduction in cerebral blood flow is unclear. The present study investigated whether aerobic exercise training can increase cerebral blood flow in postmenopausal women. Methods: Twenty healthy postmenopausal women were assigned to either the exercise training group (n = 10) or the control group (n = 10). The exercise group completed 8 weeks of moderate aerobic exercise intervention. The control group did not change their physical activity level. Before and after each intervention, middle cerebral blood flow velocity and cerebrovascular resistance were measured using transcranial Doppler ultrasonography. Results: The baseline middle cerebral blood flow velocity, cerebrovascular resistance, and most other key dependent variables did not significantly differ between the groups. Aerobic exercise training significantly increased middle cerebral blood flow velocity and significantly decreased cerebrovascular resistance, whereas no such changes were observed in the control group. Conclusions: We showed that aerobic exercise training increased middle cerebral blood flow velocity and decreased cerebrovascular resistance in postmenopausal women. The results of the current study suggest that regular aerobic exercise may attenuate aging-induced decrease in cerebral blood flow.

Stiffening of central conduit arteries –areas where the mechanoreceptors are embedded (e.g., ascending aorta and carotid artery) – is considered to be associated with the impaired baroreflex control in response to hypotensive stress. Arterial stiffness is modulated by vascular tone transiently and dynamically, however, it is unknown whether a transient change in the carotid artery stiffness influences the cardiac baroreflex response to a rapid hypotension. We measured (n = 11) carotid arterial stiffness (via concurrent applanation tonometory and ultrasound imaging) at supine rest and during 20-degree head-up tilt (HUT). To evaluate the cardiac baroreflex response, acute hypotension was evoked by releasing bilateral thigh cuffs after 3 min of suprasystolic resting ischemia at each posture; cardiac baroreflex sensitivity (e.g., change in heart rate for a given change in mean arterial pressure, ΔHR/ΔMAP) and latency (e.g., the time to peak HR response) was estimated. Carotid β-stiffness index, a measure of arterial stiffness, was reduced by 14% during HUT (P < 0.05 vs. supine position). Although cardiac baroreflex responses were unaltered, the within-group biological variability in the cardiac baroreflex sensitivity and latency from the supine to HUT was correlated with the corresponding changes in carotid arterial stiffness (r = 0.66 and r = 0.64, respectively, both P < 0.05). These findings suggest that a transient change in carotid arterial stiffness, at least in part, influences changes in the cardiac baroreflex response to a rapid hypotension.

Synchronization of heart rate and step rate has been hypothesized to create a hemodynamically favorable situation where heart motion and bodily motion are in constant harmony so that stroke volume and cardiac output enhanced and oxygen delivery to the tissues is increased. The primary aim of the present investigation was to determine the impact of synchronization of step rate and heart rate on cardiovascular functions. Twenty-three apparently healthy subjects performed treadmill running in three different conditions, one that the step rate was matched with the heart rate (matched condition), one that the step rate was ~10 steps greater or lower than heart rate (unmatched conditions). Beat-by-beat blood pressure was measured using the finger plethysmography, and stroke volume and cardiac output were calculated using the validated Model Flow method. Average heart rate and blood pressures were not different among the 3 conditions. There were no differences in double products among the 3 conditions. Stroke volume and cardiac output were greater (P < 0.05) in the matched condition than in the unmatched conditions. Our present results are consistent with the idea that synchronization of heart motion and bodily motion augments stroke volume and cardiac output, presumably through the mechanism similar to the arterial counterpulsation.

One of the most commonly evaluated features of the arterial pressure waveforms is augmentation index (AI). Multiple devices have been developed and marketed that measure AI at peripheral arteries. Currently, it is not known if and how these measures of AI are related. Aortic and radial AI (using SphygmoCor), radial AI (Omron), and finger AI (Itamar) were measured in 40 apparently healthy subjects. All the AI values were correlated with each other with Pearson r-values ranging from 0.78 to 0.94. The coefficients of variation ranged from 3.4 to 20.0%. We concluded that even though the absolute values derived by each technique were different, there were high and significant correlations between AI values.

There is increasing awareness that pulse wave velocity (PWV), an index of arterial stiffness, changes transiently via alteration of vascular smooth muscular tone. The aim of this study was to determine the effects of aging on the response of leg PWV to a low-intensity exercise bout. Ten older (69 ± 3 years) and 6 younger (21 ± 1 years) men were studied. Leg PWV in each subject was measured before and after a low-intensity single-leg cycling (20 W, 5 min). The younger subject group demonstrated a significant reduction in the exercised leg PWV (−8.0%) immediately after the exercise, whereas the non-exercised leg PWV did not change significantly (+2.2%). In the older subject group, no significant changes in PWV were observed in the exercised leg nor the non-exercised leg. There were no significant changes in other hemodynamic variables before or after the exercise bout in either younger or older subjects. These results indicate that the exercise-induced temporal reduction in leg arterial stiffness is blunted in older adults. The lack of exercise-induced reduction in leg PWV may be due to an age-related impairment of endothelial function.

Background: Augmented central artery wave reflection is a cardiovascular disease risk factor. Augmentation index (AI) obtained from peripheral artery waveforms provides qualitatively similar information to AI from central artery waveforms. Little information is available, however, regarding the influence of racial difference in association between central and peripheral AI. Methods: We studied 47 White adults (45 ± 17 yr, 20 women) and 94 age-matched Asian adults (45 ± 14 yr, 42 women). Results: The White group was significantly taller than the Asian group, whereas there were no significant group differences in blood pressure and heart rate. Carotid and radial AI tended to be lower in White compared with Asian adults (P < 0.10 for both). Such tendency disappeared when the difference in height was taken into account using ANCOVA (P = 0.84 and P = 0.77, respectively). Radial AI was strongly and positively correlated with carotid AI in White adults (r = 0.75, P < 0.0001) as well as in Asian adults (r = 0.82, P < 0.0001). The slope and intercept of linear regression line between radial and carotid AI of White adults were highly comparable with those of Asian adults. Conclusion: AI in the conveniently located peripheral vasculature may provide a surrogate measure of central AI irrespective of difference in race (e.g., Asian vs. White populations).

Background: Carotid–femoral pulse wave velocity (PWV) is the most established index of arterial stiffness. Yet there is no consensus on the methodology in regard to the arterial path length measurements conducted on the body surface. Currently, it is not known to what extent the differences in the arterial path length measurements affect absolute PWV values. Methods: Two hundred fifty apparently healthy adults (127 men and 123 women, 19–79 years) were studied. Carotid–femoral PWV was calculated using (1) the straight distance between carotid and femoral sites (PWVcar–fem), (2) the straight distance between suprasternal notch and femoral site minus carotid arterial length (PWV(ssn–fem)−(ssn–car)), (3) the straight distance between carotid and femoral sites minus carotid arterial length (PWV(car–fem)−(ssn–car)), and (4) the combined distance from suprasternal notch to the umbilicus and from the umbilicus to femoral site minus carotid arterial length (PWV(ssn–umb–fem)−(ssn–car)). Results: All the calculated PWV were significantly correlated with each other (r = 0.966–0.995). PWVs accounting for carotid arterial length were 16–31% lower than PWVcar–fem. PWVcar–fem value of 12 m/s corresponded to 8.3 m/s for PWV(ssn–fem)−(ssn–car), 10.0 m/s for PWV(car–fem)−(ssn–car), and 8.9 m/s for PWV(ssn–umb–fem)−(ssn–car). Conclusion: Different body surface measurements used to estimate arterial path length would produce substantial variations in absolute PWV values.

Central augmentation index (AI) is an index for arterial stiffness and wave reflection, but the measurement requires technical precision. We recently reported that AI obtained directly from radial arterial pressure waveforms (without using the general transfer function) could provide equivalent information to carotid AI in healthy adults. The aim of the present study was to determine whether such association would exist among patients on anti-hypertensive drugs. Forty-six hypertensive patients taking blood pressure lowering medications (62 ± 9 years, mean ± SD) and 78 age-matched apparently healthy adults (60 ± 9 years) were studied. Carotid and radial AI were obtained using arterial applanation tonometry, and radial AI was calculated using the equation [(second peak radial systolic pressure - diastolic pressure)/(first peak radial systolic pressure - diastolic pressure) × 100]. Radial AI was strongly and positively correlated with carotid AI in medicated patients (r = 0.73, P < 0.0001) as well as in healthy controls (r = 0.84, P < 0.0001). The Brand–Altman plot demonstrated that the difference and SD between carotid and radial AI were not different between medicated patients and healthy controls (61.8 ± 7.7 vs 63.0 ± 7.7%). These results suggest that radial AI may be able to provide qualitatively similar information to carotid AI even in patients on antihypertensive medications.