Maximizing the Flap Inflow in a Foot Reconstruction: Ultrasonographic Evaluation of Artery Flow in Accordance with the Angle of the Ankle.

SUMMARY: Adequate arterial inflow is mandatory for a successful free tissue transfer. Maximizing this inflow appears to be especially important during distal lower extremity reconstruction, where perfusion pressures can be significantly lower than in the trunk or head and neck. In the current study, the authors used color and pulsed-wave Doppler ultrasonography to analyze blood flow volumes in the foot in accordance with the ankle position. Twenty feet of 10 healthy subjects were included in the analyses. All subjects were examined by Doppler ultrasonography at three different ankle angles (dorsiflexion at 90 degrees, relaxed position, and complete plantar flexion). The average flow volumes of the dorsalis pedis artery varied dramatically at the different ankle positions, as follows: dorsiflexion, 19.81 ± 3.88 ml/minute; relaxed position, 11.71 ± 4.72 ml/minute; and plantar flexion, 3.47 ± 1.41 ml/minute. The average flow volume of the posterior tibial artery also varied dramatically at these different ankle positions: dorsiflexion, 9.08 ± 8.25 ml/minute; relaxed position, 14.78 ± 2.45 ml/minute; and plantar flexion, 19.03 ± 5.03 ml/minute. The ankle position dramatically affects the flow velocity in the anterior and posterior tibial vessels, which is an important consideration when performing free tissue transfer reconstruction of the foot. Ankle dorsiflexion would be recommended when using the anterior tibial artery as a recipient vessel, whereas plantar flexion of the ankle would be advised when the posterior tibial artery is used as a recipient vessel.

Resistance training with blood flow restriction: Impact on the muscle strength and body composition in people living with HIV/AIDS.

The aim of the study was to compare the impact of 12-week resistance training with blood flow restriction (GRTBFR) versus, traditional resistance training (GTRT) and non-training on the muscle strength and body composition HIV/AIDS participants. Muscle strength was tested at baseline, and on the 6th, 21st and 36th training sessions, using maximal repetition test. Pre- and post-intervention body composition changes were measured by dual-energy X-ray absorptiometry. Resistance training was undertaken three times a week comprising bilateral elbow extension and flexion exercises, unilateral flexion and bilateral knee extension. Changes in strength and body composition (pre- and post-intervention) between groups were evaluated by mixed models of repeated measures, and by paired and unpaired comparisons, considering the Effect Size. All groups were similar at baseline for muscle strength and body composition. Post-intervention, the training groups showed similar, statistically significant increases in muscle strength (GRTBFR=25.7-57.4%; GTRT=24.5-52.3%) and skeletal muscle tissue (GRTBFR=8.4%; GTRT=8.3%). There was also a significant change in body fat (p=0.023-0.043), with significant effect sizes for strength and skeletal muscle tissue (0.41-2.27), respectively. These results suggest that both resistance training interventions promoted muscle hypertrophy, body fat reduction and positive impact on muscle strength in people living with HIV/AIDS. Resistance training with blood flow restriction proved to be an effective alternative to include patients with marked physical weakness, unable to engage in regular strength training programme.ClinicalTrials.gov identifier: NCT02783417.

Effect of stifle flexion on the position of the cranial tibial artery relative to the proximal tibia in dogs.

OBJECTIVE: To determine the effect of stifle flexion on the proximity of the cranial tibial artery to the proximal tibia in canine stifles with an intact or transected cranial cruciate ligament (CCL). STUDY DESIGN: Ex vivo randomized blinded computed tomographic angiographic study. SAMPLE POPULATION: Fifteen pelvic limbs from eight greyhound cadavers. METHODS: The femoral artery and vein were cannulated and injected with 10 mL of iohexol. Each limb was placed in lateral recumbency on an acrylic sheet with predrawn femoral and tibial lines representing angles of stifle extension. Computed tomography was performed before (limbs 1-15) and after (limbs 10-15) CCL transection. The shortest distance between the cranial tibial artery and proximal tibia (dCrTA-PT) was measured at a distance of one patellar length from medial intercondylar tubercle. RESULTS: Median dCrTA-PT in intact specimens at 70°, 90°, 110°, and 135° was 2.04, 2.05, 2.28, and 2.51 mm, respectively (P = .008). Pairwise comparisons identified a difference between 70° and 135° (P = .007). Mean dCrTA-PT in transected specimens at 70°, 90°, 110°, and 135° was 2.60, 2.57, 2.90, and 2.79 mm, respectively (P = .208). Median overall dCrTA-PT was 2.24 mm in intact specimens (limbs 1-15, all four angles of extension combined) and 2.76 mm in transected specimens (limbs 10-15, all angles combined; P = .01). CONCLUSION: Flexion of the stifle resulted in a negligible decrease in dCrTA-PT in intact specimens but had no effect in CCL transected stifles. CLINICAL SIGNIFICANCE: The angle of stifle extension does not appear to have any clinically significant effect on the proximity of cranial tibial artery to the proximal tibia.

The Effect of Muscle Exercise on Perforators Flow: A Prospective Cohort Study.

Background and objectives: The metabolic response after exercise causes a significant increase in the muscle blood flow. While these effects are demonstrated for intra-muscular vessels, there is no evidence about the inter-muscular vessels, such as the septocutaneous perforators supplying the skin after they branch out from the deep source artery. The aim of our prospective study was to quantify the changes in the anterior tibial artery perforators arterial blood flow after mild isotonic exercise in a young and healthy population. Material and Methods: We performed a prospective analysis of 34 patients who were admitted to the Plastic Surgery Department from December 2019 to April 2020. Flow velocities of two previously identified anterior tibial artery perforators were recorded both before and after 10 complete flexion-extensions of the foot. The time to revert to basal flow was measured. We further classified the overmentioned patients based on their level of physical activity. Results: We registered a significant increase in systolic, diastolic and mean blood flow velocities both in proximal and distal anterior tibial artery perforators after exercise. Fitter patients exhibited a higher increase in proximal leg perforators than those who did less than three aerobic workouts a week. The time to return to basal flow ranged from 60 to 90 s. Conclusions: This was the first study to describe the effect of muscular activity on perforators blood flow. Even mild exercise significantly increases the perforator flow. Waiting at least two minutes at rest before performing the Doppler study, thus avoiding involved muscle activation, can notably improve the reliability of the pre-operative planning.

Posterior tibial perforators relationship with superficial nerves and veins: A cadaver study.

BACKGROUND: Most authors have evaluated the location of lower leg arterial perforators, but little is still known about the relationship between the arterial network and great saphenous vein (GSV) and saphenous nerve (SN). The aim of this study is to evaluate the relationship between the arterial network of the posterior tibial artery perforators, the cutaneous nerves, and the superficial venous system in the lower one third of the leg. METHODS: Eighteen lower limbs from cadavers were used for this study. The arterial and venous compartment were selectively injected with a mixture of barium sulfate and epoxy. The specimen were CT scanned and the superficial veins, nerves, and the arterial perforators were dissected. RESULTS: A large perforator of the posterior tibial artery was found at a mean distance of 6.23 cm ± 0.88, with a 95% CI: 5.79-6.67, from the medial malleolus. The average diameter was 0.9 mm ± 0.17, with a 95% CI: 0.81-0.99. In 67% the connection of the venae comitantes to the superficial venous system was established with the GSV, in the other cases, with Leonardo's vein. Both dissection and imaging studies showed perineural interperforator connections along the branches of SN in all the specimens examined. CONCLUSIONS: The distribution pattern of posterior tibial artery perforators followed the superficial nerves in this region. There is an interperforator anastomotic network along the SN. The various patterns of the venous drainage system, in relationship to the distribution of the branches of posterior tibial artery perforators, have been clarified.

Impact of Prolonged Sitting on Peripheral and Central Vascular Health.

Prolonged, uninterrupted sitting negatively impacts markers of peripheral vascular health, particularly, vasodilatory function of leg arteries. Whether sitting can similarly impact measures of central vascular health, as well as overall leg vasoreactivity (i.e., vasodilatory and vasoconstrictor function) remains unknown. To address this, measurements were made in relatively healthy participants (i.e., free of overt disease; n = 20, age = 26 ± 7; body mass index = 30 ± 7 kg/m2; 7 female) pre, during and post 3 hours of uninterrupted sitting. Measures of central vascular health included arterial wave reflection (augmentation index and Reflection Magnitude-RM%) and aortic vascular stiffness (aortic pulse wave velocity). Local vasoreactivity of the distal, posterior tibial artery was measured using flow-mediated dilation-FMD, coupled with low-flow mediated constriction, and microvascular function was assessed through the total hyperemic blood velocity (area-under-curve) response during FMD. After sitting, there was a significant increase in aortic pulse wave velocity (pre sit = 5.7 ± 0.3 vs post sit = 6.1 ± 0.3 m/s; p = 0.009, d = 0.36), whereas, augmentation index decreased (pre sit = 13 ± 3 vs post sit = 3 ± 1%; p < 0.001, d = 0.71). Albeit a moderate effect for decrease, RM% was not significantly altered during sitting (p = 0.13, d = 0.3). Vasodilatory (i.e., FMD pre sit = 0.5 ± 0.04 vs post sit = 0.3 ± 0.04 mm; p = 0.014, d = 0.29) and microvascular function (i.e., Microvascular area-under-curve: pre sit = 2,196 ± 333 vs 1,157±172 AU; p = 0.003, d = 0.31) decreased, but vasoconstrictor function (low-flow mediated constriction; p = 0.85, d = 0.005) was unaffected by sitting. In conclusion, these data demonstrate that a prolonged bout of uninterrupted sitting negatively impacts markers of peripheral and central vascular health in relatively healthy adults.

The Importance of Patency of Tibial Run Off Arteries on Clinical Outcomes After Stenting for Chronic Total Occlusions in the Superficial Femoro-popliteal Artery.

OBJECTIVE/BACKGROUND: The aim was to evaluate the impact of patent tibial arteries on stenting for chronic total occlusions (CTO) in superficial femoropopliteal artery (SFA) lesions. Additionally, the efficacy of additive tibial percutaneous transluminal angioplasty (PTA) was evaluated. METHODS: A total of 238 limbs in 199 patients with de novo SFA CTO lesions treated with bare nitinol stents between 2009 and 2015 were retrospectively identified. These limbs were divided into two groups (group A [number of patent tibial arteries at baseline angiogram ≥ 2, 127 limbs in 104 patients] vs. group B [number of patent tibial arteries at baseline angiogram ≤ 1, 111 limbs in 95 patients]). Furthermore, the efficacy of additive tibial PTA on stenting for SFA CTO lesions was evaluated by comparing subgroups (group B with tibial PTA vs. without tibial PTA). The primary end point was freedom from major adverse limb events (MALE) two years after PTA, defined as a composite of ischaemic driven target lesion revascularisation (TLR) and major amputation. RESULTS: Group A had a significantly higher MALE free survival rate two years after PTA compared with group B (80.9% vs. 43.5%; p < .001), which was mainly driven by higher TLR free survival rates (80.9% vs. 45.9%; p < .001). In subgroup analysis, patients in group B with tibial PTA had significantly higher MALE free survival rate at two years compared with those without tibial PTA (65.5% vs. 26.2%; p = .001). CONCLUSION: The presence of patent tibial arteries was an important predictor of MALE after PTA for SFA CTO lesions. Furthermore, additional tibial PTA on SFA CTO stenting might be beneficial for clinical outcomes.

Arterial tree anomalies in patients with clubfoot: an investigation carried out at Soba University Hospital.

Vascular deficiencies and reduced perfusion of the anterior tibial artery and the dorsalis pedis artery were suggested as causes of congenital talipes equino varus (CTEV). In this study, we assessed the prevalence of arterial abnormalities in patients with CTEV (50 patients; 74 feet) compared with a normal control group (16 patients; 32 feet) by Doppler ultrasound and Ankle Brachial Index. The flow was normal in the control group and was deficient in 39.19% of clubfoot patients. In severe clubfoot cases, the deficiency was found to an extent of 76.67%. In conclusion, the anterior tibial artery and dorsalis pedis artery are deficient in CTEV patients; to avoid postoperative skin sloughing, arterial supply must be protected using a judicious incision.

[CHANGES IN RHEOGRAPHIC INDICATORS OF SHIN IN ATHLETES OF DIFFERENT KINDS OF SPORTS].

We determined the changes of time, amplitude and derivatives of these indicators of rheovasograms of shin in sportsmen of youth age and high level of skills engaged in volleyball, athletics and wrestling with sports experience at least 3 years. We determined significant differences in the value of time, amplitude and derivatives of these indicators ofrheovazograms of shin in males youth age, depending on the impact of intense exercise. The volleyball players compared to youth who do not exercise, reliably large values of the overall tone of the arteries (11,2%), arteries of large diameter (8,2%), arteries of medium and small diameters (13,5%), time ascending part of rheovazograms (2%) and a slow passage (5,9%) and less dycrotycs index (17%), duration ofrheographic wave (3,7%), time descending part of rheovazograms (10%). The persons of control group had higher values of baseline impedance than wrestlers (9,9%) and athletes (13,7%) and all amplitude indicators rheograms of the shin than athletes (average 12-15%) and wrestlers (22-23%). The size and volume of blood flow to the arteries of the extremities adapted to the metabolic needs of the relevant muscles. In volleyball players compared to the athletes, a lower duration of rheographic wave (10%), time of downlink part of the rheograms (12,7%), the base impedance (17,2%), amplitude of the systolic wave (17%) and rapid blood filling (21%), all indicators tone of arteries (12,2-16,9%) and greater value of time of rising part of rheograms (3,5%) and slow blood filling (5,9%). Wrestlers compared to the athletes have a lower duration of rheographic wave (6,1%), time of downlink part of the rheograms (6,1%), the amplitude of the systolic wave (9,3%), compared with volleyball players set lower values of average speed of fast blood filling (15,6%), tone of arteries with different diameters (15-16,5%), all amplitude indicators (20-28%), time slow blood filling (9,7%), ascending parts rheogram (10,3%). Thus, the level ofphysical activity and especially muscle activity has a significant effect on the performance of regional blood flow.

Assessment of pulse arrival time for arterial stiffness monitoring on body composition scales.

This study presents a system that aims to estimate changes in arterial health status in an unobtrusive way. It might be especially useful in long-term self-monitoring of cardiovascular performance for successful treatment and empowerment of patients. This system applies the electrocardiographic and impedance plethysmographic signals acquired using modified body composition scales for the calculation of pulse arrival time, which is directly related to arterial stiffness. The proposed device was tested in a cohort of 14 subjects. The modified scales were compared to the commercial PulsePen tonometer and the results showed significant relationship between these different devices (rs=0.93, p<0.01). The system also showed the ability to track small pulse arrival time variations induced by paced respiration. These findings suggest that scales evaluating parameters of cardiovascular function have potential to become a convenient device for self-monitoring of arterial stiffness.

Vascular Function and Intima-media Thickness of a Leg Artery in Peripheral Artery Disease: A Comparison of Buerger Disease and Atherosclerotic Peripheral Artery Disease.

AIM: Both vascular function and structure are independent predictors of cardiovascular events. The purpose of this study was to evaluate vascular function and structure of a leg artery in patients with peripheral artery disease (PAD). METHODS: We measured flow-mediated vasodilatation (FMD) and nitroglycerine-induced vasodilation (NID) as indices of vascular function and intima-media thickness (IMT) as an index of vascular structure of the popliteal artery in 100 subjects, including 20 patients with Buerger disease and 30 patients with atherosclerotic PAD, 20 age- and sex-matched subjects without Buerger disease (control group) and 30 age- and sex-matched patients without atherosclerotic PAD (control group). RESULTS: IMT was significantly larger in the Buerger group than in the control group (Buerger, 0.63± 0.20 mm; control, 0.50±0.07 mm; P=0.01), whereas there were no significant differences in FMD and NID between the two groups. IMT was significantly larger in the atherosclerotic PAD group than in the control group (atherosclerotic PAD, 0.80±0.22 mm; control, 0.65±0.14 mm; P＜0.01), and FMD and NID were significantly smaller in the atherosclerotic PAD group than in the control group (FMD: atherosclerotic PAD, 3.9%±1.1%; control, 5.0%±1.8%; P＜0.01; and NID: atherosclerotic PAD, 6.1%±2.0%; control, 8.4%±2.1%; P＜0.01). CONCLUSION: These findings suggest that vascular function is preserved in patients with Buerger disease and that both vascular function and vascular structure are impaired in patients with atherosclerotic PAD.

Quantification of residual limb skeletal muscle perfusion with contrast-enhanced ultrasound during application of a focal junctional tourniquet.

OBJECTIVE: Focal junctional tourniquets (JTs) have been developed to control hemorrhage from proximal limb injuries. These devices may permit greater collateral perfusion than circumferential tourniquets. We hypothesized that JTs eliminate large-vessel pulse pressure yet allow a small amount of residual limb perfusion that could be useful for maintaining tissue viability. METHODS: Ten healthy control subjects were studied. Transthoracic echocardiography, Doppler ultrasound of the femoral artery (FA) and posterior tibial artery, and contrast-enhanced ultrasound (CEU) perfusion imaging of the anterior thigh extensor and calf plantar flexor muscles were performed at baseline and during application of a JT over the common FA. Intramuscular arterial pulsatility index was also measured from CEU intensity variation during the cardiac cycle. RESULTS: FA flow was eliminated by JTs in all subjects; posterior tibial flow was eliminated in all but one. Perfusion measured in the thigh and calf muscles was similar at baseline (0.33 ± 0.29 vs 0.29 ± 0.22 mL/min/g). Application of the JT resulted in a reduction of perfusion (P < .05) that was similar for the thigh and calf (0.08 ± 0.07 and 0.10 ± 0.03 mL/min/g). On CEU, microvascular flux rate was reduced by ≈55%, and functional microvascular blood volume was reduced by ≈35%. Arterial pulsatility index was reduced by ≈90% in the calf. JT inflation did not alter left ventricle dimensions, fractional shortening, cardiac output, or arterial elastance as a measure of total systolic load. CONCLUSIONS: Application of a JT eliminates conduit arterial pulse and markedly reduces intramuscular pulse pressure, but thigh and calf skeletal muscle perfusion is maintained at 25% to 35% of basal levels. These data suggest that JTs that are used to control limb hemorrhage allow residual tissue perfusion even when pulse pressure is absent.

Acute moderate exercise does not attenuate cardiometabolic function associated with a bout of prolonged sitting.

Epidemiological studies suggest that prolonged sitting increases all-cause mortality; yet, physiological causes underpinning prolonged sitting remain elusive. We evaluated cardiometabolic function during prolonged sitting (5 h) in 10 adults with and without 30 min of moderate exercise leading up to the sitting. Mean arterial blood pressure (MAP), heart rate (HR) and posterior tibial artery blood velocity were measured at baseline and every hour subsequently. Blood glucose was measured at baseline, 3 and 5 h, with consumption of a caloric beverage at 1 h. Seated MAP and HR values were ~17 mmHg (P < 0.001) and ~4 bpm (P < 0.05) higher for the moderate exercise versus sitting conditions. A ~ 4 cm·s(-1) (16%) (P < 0.05) decline in posterior tibial artery blood velocity from prolonged sitting was observed, with no benefit conferred from moderate exercise. Postprandial glucose metabolism was not different between conditions (P > 0.05). We conclude prolonged sitting may be related to decreased posterior tibial artery blood velocity. Moreover, an acute bout of moderate exercise does not seem to attenuate cardiometabolic function during prolonged sitting in healthy, young adults.

Clinical assessment of arterial stiffness with cardio-ankle vascular index: theory and applications.

Arterial stiffness is often assessed in clinical medicine, because it is not only an important factor in the pathophysiology of blood circulation but also a marker for the diagnosis and the prognosis of cardiovascular diseases. Many parameters have so far been proposed to quantitatively represent arterial stiffness and distensibility, such as pressure-strain elastic modulus (Ep), stiffness parameter (ß), pulse wave velocity (PWV), and vascular compliance (Cv). Among these, PWV has been most frequently applied to clinical medicine. However, this is dependent on blood pressure at the time of measurement, and therefore it is not appropriate as a parameter for the clinical evaluation of arterial stiffness, especially for the studies on hypertension. On the contrary, stiffness parameter ß is an index reflecting arterial stiffness without the influence of blood pressure. Recently, this parameter has been applied to develop a new arterial stiffness index called cardio-ankle vascular index (CAVI). Although this index is obtained from the PWV between the heart and the ankle, it is essentially similar to the stiffness parameter ß, and therefore it does not depend on blood pressure changes during the measurements. CAVI is being extensively used in clinical medicine as a measure for the evaluation of cardiovascular diseases and risk factors related to arteriosclerosis. In the present article, we will explain the theoretical background of stiffness parameter ß and the process to obtain CAVI. And then, the clinical utility of CAVI will be overviewed by reference to recent studies.

Blood flow and muscle oxygenation during low, moderate, and maximal sustained isometric contractions.

A reduction of blood flow to active muscle will precipitate fatigue, and sustained isometric contractions produce intramuscular and compartmental pressures that can limit flow. The present study explored how blood flow and muscle oxygenation respond to isometric contractions at low, moderate, and maximal intensities. Over two visits, 10 males (26 ± 2 yr; means ± SD) performed 1-min dorsiflexion contractions at 30, 60, and 100% of maximal voluntary contraction (MVC) torque. Doppler ultrasound of the anterior tibial artery was used to record arterial diameter and mean blood velocity and to calculate absolute blood flow. The tissue oxygenation index (TOI) of tibialis anterior was acquired with near-infrared spectroscopy (NIRS). There was a progressive increase in blood flow at 30% MVC (peak of 289 ± 139% resting value), no change from rest until an increase in the final 10 s of exercise at 60% MVC (peak of 197 ± 102% rest), and an initial decrease (59 ± 30% resting value) followed by a progressive increase at 100% MVC (peak of 355 ± 133% rest). Blood flow was greater at 30 and 100% than 60% MVC during the last 30 s of exercise. TOI was ∼63% at rest and, within 30 s of exercise, reached steady-state values of ∼42%, ∼22%, and ∼22% for 30, 60, and 100% MVC, respectively. Even maximal contraction of the dorsiflexors is unable to cause more than a transient decrease of flow in the anterior tibial artery. Unlike dynamic or intermittent isometric exercise, our results indicate blood flow is not linearly graded with intensity or directly coupled with oxygenation during sustained isometric contractions.

Comparisons between low-intensity resistance training with blood flow restriction and high-intensity resistance training on quadriceps muscle mass and strength in elderly.

High-intensity resistance training (HRT) has been recommended to offset age-related loss in muscle strength and mass. However, part of the elderly population is often unable to exercise at high intensities. Alternatively, low-intensity resistance training with blood flow restriction (LRT-BFR) has emerged. The purpose of this study was to compare the effects of LRT-BFR and HRT on quadriceps muscle strength and mass in elderly. Twenty-three elderly individuals, 14 men and 9 women (age, 64.04 ± 3.81 years; weight, 72.55 ± 16.52 kg; height, 163 ± 11 cm), undertook 12 weeks of training. Subjects were ranked according to their pretraining quadriceps cross-sectional area (CSA) values and then randomly allocated into one of the following groups: (a) control group, (b) HRT: 4 × 10 repetitions, 70-80% one repetition maximum (1RM), and (c) LRT-BFR: 4 sets (1 × 30 and 3 × 15 repetitions), 20-30% 1RM. The occlusion pressure was set at 50% of maximum tibial arterial pressure and sustained during the whole training session. Leg press 1RM and quadriceps CSA were evaluated at before and after training. A mixed-model analysis was performed, and the significance level was set at p ≤ 0.05. Both training regimes were effective in increasing pre- to post-training leg press 1RM (HRT: ∼54%, p < 0.001; LRT-BFR: ∼17%, p = 0.067) and quadriceps CSA (HRT: 7.9%, p < 0.001; LRT-BFR: 6.6%, p < 0.001); however, HRT seems to induce greater strength gains. In summary, LRT-BFR constitutes an important surrogate approach to HRT as an effective training method to induce gains in muscle strength and mass in elderly.

Hypotensive effects of resistance exercises with blood flow restriction.

The effects of low-intensity resistance exercise (RE) combined with blood flow restriction (BFR) on blood pressure (BP) are an important factor to be considered because of the acute responses imposed by training. The aim of this study was to compare the hypotensive effect of RE performed with and without BFR in normotensive young subjects. After 1 repetition maximum (1RM) tests, 24 men (21.79 ± 3.21 years; 1.72 ± 0.06 m; 69.49 ± 9.80 kg) performed the following 4 experimental protocols in a randomized order: (a) high-intensity RE at 80% of 1RM (HI), (b) low-intensity RE at 20% of 1RM (LI), (c) low-intensity RE at 20% of 1RM combined with partial BFR (LI + BFR), and (d) control. Analysis of systolic blood pressure (SBP) and diastolic blood pressure (DBP) was conducted over a 60-minute period. The 3 RE protocols resulted in hypotensive SBP (HI = -3.8%, LI = -3.3%, LI + BFR = -5.5%) responses during the 60 minutes (p ≤ 0.05). The LI + BFR protocol promoted hypotensive (-11.5%) responses in DBP during the 60 minutes (p ≤ 0.05), and both the HI and LI + BFR protocols resulted in mean blood pressure (MBP) hypotension between 30 (-7.0%, -7.7%) and 60 minutes (-3.6%, -8.8%), respectively. In conclusion, postexercise hypotension may occur after all 3 exercise protocols with greater reductions in SBP after HI and LI + BFR, in DBP after LI + BFR, and in MBP after HI and LI + BFR protocols.

Does the Ponseti technique affect the vascular development in patients with congenital talipes equinovarus?

In this study, we have evaluated the changes observed in the main arteries of the foot before and after the Ponseti technique. Arterial structures of seven patients were examined using Doppler ultrasound and the parameters studied included the course of the arteries, lumen filling, flow direction, pattern, and velocity. Before the treatment, the side with congenital talipes equinovarus deformity showed decreased blood flow in all arteries, except for the posterior tibial artery. At the second examination, the increase in the flow velocity of both arteries except tibialis anterior arteries was statistically significant. The Ponseti method results in normalization of the arterial structures in extremities with congenital talipes equinovarus.

Differential mechanisms for insulin-induced relaxations in mouse posterior tibial arteries and main mesenteric arteries.

The characteristics of endothelium-dependent relaxations in response to insulin and acetylcholine (ACh) in the mouse posterior tibial artery (PTA) were studied on wire myograph, and compared to those in the mouse main mesenteric artery (MMA). Insulin-induced relaxation in PTA was reversed by PI3K and Akt inhibitors, LY294002 and triciribine, but not by nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME) or guanylate cyclase inhibitor, ODQ. The relaxation in PTA was also inhibited by apamin (small-conductance Ca(2+)-activated K(+) channel blocker) plus charybdotoxin (intermediate-conductance Ca(2+)-activated K(+) channel blocker), elevated KCl or ouabain (Na(+)-K(+) ATPase inhibitor) plus BaCl(2) [inwardly rectifying K(+) (K(IR)) channel inhibitor]; whereas L-NAME but not triciribine inhibited ACh-induced relaxation in PTA. On the other hand, nitric oxide and endothelium-derived hyperpolarizing factor albeit to a less extent mediated both insulin- and ACh-induced relaxations in MMA. The present study is for the first time dissecting out the components of endothelium-dependent relaxation in mouse PTA and suggesting differential responses to different agonists in distinctive blood vessels.

Evaluation of blood pressure control using a new arterial stiffness parameter, cardio-ankle vascular index (CAVI).

Arterial stiffness has been known to be a surrogate marker of arteriosclerosis, and also of vascular function. Pulse wave velocity (PWV) had been the most popular index and was known to be a predictor of cardiovascular events. But, it depends on blood pressure at measuring time. To overcome this problem, cardio-ankle vascular index (CAVI) is developed. CAVI is derived from stiffness parameter ß by Hayashi, and the equation of Bramwell-Hill, and is independent from blood pressure at a measuring time. Then, CAVI might reflect the proper change of arterial wall by antihypertensive agents. CAVI shows high value with aging and in many arteriosclerotic diseases and is also high in persons with main coronary risk factors. Furthermore, CAVI is decreased by an administration of α1 blocker, doxazosin for 2-4 hours, Those results suggested that CAVI reflected the arterial stiffness composed of organic components and of smooth muscle cell contracture. Angiotensin II receptor blocker, olmesartan decreased CAVI much more than that of calcium channel antagonist, amlodipine, even though the rates of decreased blood pressure were almost same. CAVI might differentiate the blood pressure-lowering agents from the point of the effects on proper arterial stiffness. This paper reviewed the principle and rationale of CAVI, and the possibilities of clinical applications, especially in the studies of hypertension.