A Cross-Sectional Study Evaluating the Association of Brachial Artery Flow Mediated Vasodilation with Physical Activity Measured by Accelerometry in Patients with the Overlap of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease.

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in Overlap Syndrome (OS), the co-occurrence of Obstructive Sleep Apnea and Chronic Obstructive Pulmonary Disease. Clustering of patients in subgroups with similar pre-clinical manifestations (ie, endothelial dysfunction) may identify relevant therapeutic phenotype categories for patients with OS who are at high risk of CVD. We therefore conducted a cross-sectional pilot study of endothelial function in 7 patients with OS (Forced Expiratory Volume in 1 second/Forced Vital Capacity < 0.7) on continuous positive airway pressure therapy (n = 7) to assess the relationship between FMD and physical activity. We found a strong association between FMD and step counts (rho = 0.77, p = 0.04); and FMD and moderate physical activity (rho = 0.9, p = 0.005). Further, larger studies are needed to confirm that FMD may identify patients with OS at high risk of CVD who benefit from increased physical activity.

Short-term vascular responses to spring and fall daylight savings time shifts.

Daylight saving time (DST) is a Western biannual time transition, setting the clock back 1 h in the fall and forward 1 h in the spring. There is an epidemiological link between DST and acute myocardial infarction risk in the first week following the spring shift; however, the mechanisms underlying the effect of DST on cardiovascular function remain unclear. The purpose of this study was to explore the short-term cardiovascular changes induced by fall and spring shifts in DST in a convenience sample of healthy adults. We hypothesized that spring, but not fall, DST shifts would acutely increase central pulse wave velocity, the gold standard measurement of central arterial stiffness. Twenty-one individuals (fall: n = 10; spring: n = 11) participated in four visits, occurring 1 wk before and at +1, +3, and +5 days after spring and fall time transitions. Central, brachial, and radial pulse wave velocity as well as carotid augmentation index were assessed with applanation tonometry. Sleep quality and memory function were assessed via questionnaire and the Mnemonic Similarities Task, respectively. Neither fall or spring transition resulted in changes to cardiovascular variables (carotid-femoral pulse wave velocity, carotid-brachial pulse wave velocity, carotid-radial pulse wave velocity, heart rate, mean arterial pressure, or augmentation index), sleep quality, or cognitive function (all P > 0.05). Our findings do not provide evidence that DST shifts influence cardiovascular outcomes in healthy adults. This study emphasizes the need for further research to determine the mechanisms of increased cardiovascular disease risk with DST that help explain epidemiological trends.NEW & NOTEWORTHY The debate of whether to abolish daylight savings time (DST) is, in part, motivated by the population-level increase in all-cause mortality and incidence of cardiovascular events following DST; however, there is an absence of data to support a physiological basis for risk. We found no changes in pulse wave velocity or augmentation index during the subacute window of DST. Large multisite trials are necessary to address the small, but meaningful, effects brought on by a societal event.

Ultrasound-guided thrombin injection in the management of brachial artery pseudoaneurysm with median nerve compression.

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Unilateral identification of a rare superficial brachioulnoradial artery contributing to the superficial palmar arch and brachial artery continuing as the interosseous artery: a case report.

The occurrence of variations in human arterial branching of the upper limb has been commonly reported in peer-reviewed literature. However, the variability of upper limb arterial patterns may be underappreciated in medical practice, which can result in clinical and surgical errors. Here we report a case of a rare, unilateral arterial variation of the left upper limb of a 76-year-old Caucasian male cadaver, discovered during a routine educational dissection. Observed characteristics of the variation include a high brachial artery bifurcation into a superficial brachioulnoradial artery and brachial artery continuing as the interosseous artery and then a bifurcation of the superficial brachioulnoradial artery into a superficial radial and a superficial ulnar artery, which eventually contribute to the formation of the superficial palmar arch. The anatomical characteristics, prevalence, embryological origin, and clinical significance of the variation are discussed.

[Clinical effect of anterolateral thigh flow-through chimeric perforator free flap transplantation in the treatment of upper limb complex tissue defects with main artery injury].

Objective: To investigate the clinical effect of anterolateral thigh flow-through chimeric perforator free flap transplantation in the treatment of upper limb complex tissue defects with main artery injury. Methods: The study was a retrospective observational study. From May 2019 to January 2022, 11 patients with upper limb complex tissue defects combined with main artery injury who met the inclusion criteria were admitted to the Department of Hand, Foot and Ankle Surgery of General Hospital of Ningxia Medical University, including 7 males and 4 females, aged from 18 to 56 years. After debridement, the area of skin and soft tissue defects was from 20 cm×6 cm to 32 cm×10 cm, and the exposed area of dead cavity or deep tissue was from 7 cm×4 cm to 10 cm×7 cm. Three patients had radial artery defects with a length of 4 to 7 cm; two patients had ulnar artery defects with a length of 5 to 8 cm; 4 patients had defects in both ulnar and radial arteries with a length of 3 to 7 cm; and in two patients, the ulnar, radial and brachial arteries were all defective with a length of 4 to 8 cm. The anterolateral thigh flow-through chimeric perforator flap was designed and cut. The skin flap area was from 22 cm×7 cm to 32 cm×11 cm, the chimeric muscle flap area was from 7 cm×4 cm to 10 cm×7 cm, and the length of the flow-through vessel in the "T" shaped vessel pedicle was from 4 to 8 cm. When transplanting the skin flap, the proximal end of the vascular pedicle was anastomosed with the proximal end of the recipient site, and the distal end of the vascular pedicle was anastomosed with the more normal blood vessel at the distal end of the forearm; the invalid cavity was filled with the muscle flap. The donor site wounds of tissue flap were closed directly or treated with skin grafting. After operation, the blood supply and survival of the flap, the survival of the distal limb, and the survival of the skin graft at the flap donor site were observed. Computed tomography angiography (CTA) was performed to observe the patency of the proximal and distal anastomotic arteries from 2 to 4 weeks after surgery. During follow-up, the texture of the flap, the survival of the grafted skin and the healing of the donor area were observed. Results: One patient (complete forearm disconnection) developed distal limb blood disorder on 5 days after surgery. CTA examination suggested embolization of the distal anastomosis of the flow-through artery. more muscle and skin and soft tissue necrosis of the distal limb showed in emergency exploration. So, amputation was performed ultimately. No vascular crisis occurred in the skin flaps of the remaining 10 patients, and all skin flaps, distal limbs and the skin grafts in flap donor sites survived well. Two to 4 weeks after surgery, the proximal and distal ends of the anastomosed arteries were good in the patency. Follow-up for 11-37 months, the flap texture was good, and all donor site wounds healed well. Conclusions: The use of anterolateral thigh flow-through chimeric perforator flap to repair upper limb complex tissue defects accompanied by main artery injury can improve the success rate of limb salvage, which can be promoted in clinical practice.

True brachial artery aneurysm: A systematic review.

Objective: To identify and critically appraise literature on true brachial artery aneurysm, exploring its demographic characteristics, aetiologies, clinical manifestations and different methods of repair along with complication rates to determine future treatment strategies. METHODS: The systematic review was conducted at Liaquat National Hospital, Karachi, from September 30, 2021, to November 30, 2022, in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Literature was searched on MEDLINE, EMBASE and Cochrane databases for relevant studies in English language or with English translation published till May 31, 2022. The key words used for the search were "brachial artery aneurysm". Data was noted on a proforma and was subjected to descriptive analysis. RESULTS: Of 113 articles, 6 (5.3%) were retrospective studies, 7 (6.1%) were case series and 100 (88.4%) were case reports. The total number of patients involved was 157 with mean age 43.1±23.4 years (range: 2 months to 84 years). The gender was mentioned for 152(96.8%) patients; 111(73%) males and 41(27%) females. The mean diameter of true brachial artery aneurysm was 36.2 ±17.5mm and 106(67.5%) patients presented with localised swelling, 65(41.4%) with pain, 41(26.1%) with distal ischaemic symptoms, and 28(17.8%) with median nerve compression. True brachial artery aneurysms were more common in renal failure patients having a history of arteriovenous fistula creation in the affected limb and were on immunosuppressant drugs due to renal transplant 81(51.5%). Less common causes included primary/idiopathic 27(17.1%), trauma 13(8.2%), connective tissue disorders 8(5%) and vasculitis 7(4.5%). The treatment of choice was aneurysmectomy in 142(90.4%) cases, with revascularisation of limb primarily with reversed great saphenous vein graft 79(50.3 %), followed by end-to-end anastomosis of brachial artery 17(10.8%) and synthetic grafting 17(10.8%). Endovascular intervention was performed in 6(3.8%) cases to exclude true brachial artery aneurysm, and to re-establish adequate blood flow to the associated limb. Conclusion: True brachial artery aneurysm, although a rarity, may lead to significant neurological and vascular problems if ignored. Arteriovenous fistula and immunosuppression are identified as two significant risk factors in the development of true brachial artery aneurysm. Therefore, an effective long-term follow up in renal failure patients is recommended to prevent its complications. Open surgical repair has been the most preferred mode of treatment, but further significant studies are needed to explore and compare different modes of surgical intervention, like open versus endovascular, to plan future treatment strategies.

Acute inspiratory resistance training enhances endothelium-dependent dilation and retrograde shear rate in healthy young adults.

Inspiratory resistance training (IRT) yields significant reductions in resting blood pressure and improves vascular endothelial function. Our objective was to quantify the acute effects of IRT on brachial artery flow-mediated dilation (FMD) and shear rates (SRs) in healthy men and women. Twenty young adults (22.9 ± 3.4 years; 10 male, 10 female) completed a single bout of IRT or Rest condition in a randomized crossover design. Brachial artery FMD was performed before, 10 min after, and 40 min after the assigned condition. Brachial artery blood flow velocities were collected during IRT, separated by breathing cycle phase, and converted into SRs. FMD improved 10 min post-IRT (+1.86 ± 0.61%; p = 0.025) but returned to baseline by 40 min post-IRT (p = 0.002). Anterograde SR decreased by 10% and retrograde SR increased 102% during resisted inspiration, relative to baseline SR (p < 0.001). Anterograde SR increased by 7% in men and women (p < 0.001) and retrograde SR decreased by 12% in women but not men (p = 0.022) during unresisted expiration, relative to baseline SR. A single bout of IRT elicits a transient enhancement in FMD in both men and women. Acute IRT-related enhancements in SRs may contribute to sustained improvements in FMD that have been reported previously.

Ultrasonic AccV: a potential indicator of peripheral arteriosclerosis in patients with chronic obstructive pulmonary disease.

OBJECTIVE: This study aimed to investigate the risk factors for peripheral arteriosclerosis (PAS) and peripheral artery disease (PAD) in chronic obstructive pulmonary disease (COPD) patients and potential ultrasound indicators that could be used to improve detection. METHOD: Outpatients seeking care between January 1, 2017, and December 31, 2020, in The First Affiliated Hospital of China Medical University were prospectively recruited. Subjects were divided into COPD and non-COPD (control) groups, and the COPD group was further divided into PAD and non-PAD subgroup, at the same time, PAS and non-PAS subgroup. Indicators of PAD -ankle-brachial index (ABI), indicators of PAS- pulse wave velocity (PWV), and ultrasound indices -peak systolic blood flow velocity (PSV) and blood flow acceleration velocity (AccV) were compared. RESULT: Sixty-nine (61.6%) of 112 enrolled subjects had COPD. COPD patients had higher age, and blood pressure (BP)lower than controls. Seventeen (24.6%) COPD patients had PAD, the prevalence of PAD increases with the decrease of lung function, and seven (16.3%) non-COPD patients had PAD, however, there was no significant statistical difference between COPD and non-COPD groups. Fifty (72.5%) COPD patients had PAS, and thirty-four (79.1%) non-COPD patients had PAS, however, there was also no significant difference. The PAS subgroup had higher age, body mass index(BMI), body fat percentage(BFP), lower FEV1 and FEV1/FVC, as well as higher levels of right brachial artery and left dorsalis pedis artery AccV. Factors that correlated with ABI were 6MWD, post-bronchodilator FEV1, FEV1/ FVC, and maximal middle expiratory flow between 75% and 25% of FVC. Age, BP, and 6MWD, but not pulmonary function, were associated with brachial-ankle PWV (baPWV). There was a positive correlation between baPWV and radial artery AccV bilaterally. CONCLUSION: Radial artery AccV correlated well with baPWV, which suggests that ultrasound could be used to assess both morphological and functional changes in vessels, may serving as a better method to identify PAS in high-risk COPD patients.

Statin administration improves vascular function in heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is characterized by impaired vascular endothelial function that may be improved by hydroxy-methylglutaryl-CoA (HMG-CoA) reductase enzyme inhibition. Thus, using a parallel, double-blind, placebo-controlled design, this study evaluated the efficacy of 30-day atorvastatin administration (10 mg daily) on peripheral vascular function and biomarkers of inflammation and oxidative stress in 16 patients with HFpEF [Statin: n = 8, 74 ± 6 yr, ejection fraction (EF) 52-73%; Placebo: n = 8, 67 ± 9 yr, EF 56-72%]. Flow-mediated dilation (FMD) and sustained-stimulus FMD (SS-FMD) during handgrip (HG) exercise, reactive hyperemia (RH), and blood flow during HG exercise were evaluated to assess conduit vessel function, microvascular function, and exercising muscle blood flow, respectively. FMD improved following statin administration (pre, 3.33 ± 2.13%; post, 5.23 ± 1.35%; P < 0.01), but was unchanged in the placebo group. Likewise, SS-FMD, quantified using the slope of changes in brachial artery diameter in response to increases in shear rate, improved following statin administration (pre: 5.31e-5 ± 3.85e-5 mm/s-1; post: 8.54e-5 ± 4.98e-5 mm/s-1; P = 0.03), with no change in the placebo group. Reactive hyperemia and exercise hyperemia responses were unchanged in both statin and placebo groups. Statin administration decreased markers of lipid peroxidation (malondialdehyde, MDA) (pre, 0.652 ± 0.095; post, 0.501 ± 0.094; P = 0.04), whereas other inflammatory and oxidative stress biomarkers were unchanged. Together, these data provide new evidence for the efficacy of low-dose statin administration to improve brachial artery endothelium-dependent vasodilation, but not microvascular function or exercising limb blood flow, in patients with HFpEF, which may be due in part to reductions in oxidative stress.NEW & NOTEWORTHY This is the first study to investigate the impact of statin administration on vascular function and exercise hyperemia in patients with heart failure with preserved ejection fraction (HFpEF). In support of our hypothesis, both conventional flow-mediated dilation (FMD) testing and brachial artery vasodilation in response to sustained elevations in shear rate during handgrip exercise increased significantly in patients with HFpEF following statin administration, beneficial effects that were accompanied by a decrease in biomarkers of oxidative damage. However, contrary to our hypothesis, reactive hyperemia and exercise hyperemia were unchanged in patients with HFpEF following statin therapy. These data provide new evidence for the efficacy of low-dose statin administration to improve brachial artery endothelium-dependent vasodilation, but not microvascular reactivity or exercising muscle blood flow in patients with HFpEF, which may be due in part to reductions in oxidative stress.

Accurate detection of Korotkoff sounds reveals large discrepancy between intra-arterial systolic pressure and simultaneous noninvasive measurement of blood pressure with brachial cuff sphygmomanometry.

Cardiovascular disease is the number 1 cause of death globally, with elevated blood pressure (BP) being the single largest risk factor. Hence, BP is an important physiological parameter used as an indicator of cardiovascular health. Noninvasive cuff-based automated monitoring is now the dominant method for BP measurement and irrespective of whether the oscillometric or the auscultatory method is used, all are calibrated according to the Universal Standard (ISO 81060-2:2019), which requires two trained operators to listen to Korotkoff K1 sounds for SBP and K4/K5 sounds for DBP. Hence, Korotkoff sounds are fundamental to the calibration of all NIBP devices. In this study of 40 lightly sedated patients, aged 64.1 ±â€Š9.6 years, we compare SBP and DBP recorded directly by intra-arterial fluid filled catheters to values recorded from the onset (SBP-K) and cessation (DBP-K) of Korotkoff sounds. We demonstrate that whilst DBP-K measurements are in good agreement, with a mean difference of -0.3 ±â€Š5.2 mmHg, SBP-K underestimates true intra-arterial SBP (IA-SBP) by an average of 14 ±â€Š9.6 mmHg. The underestimation arises from delays in the re-opening of the brachial artery following deflation of the brachial cuff to below SBP. The reasons for this delay are not known but appear related to the difference between SBP and the pressure under the cuff as blood first begins to flow, as the cuff deflates. Linear models are presented that can correct the underestimation in SBP resulting in estimates with a mean difference of 0.2 ±â€Š7.1 mmHg with respect to intra-arterial SBP.

Intermediate versus morning chronotype has lower vascular insulin sensitivity in adults with obesity.

AIM: Chronotype reflects a circadian rhythmicity that regulates endothelial function. While the morning chronotype (MORN) usually has low cardiovascular disease risk, no study has examined insulin action on endothelial function between chronotypes. We hypothesized intermediate chronotypes (INT) would have lower vascular insulin sensitivity than morning chronotype (MORN). MATERIALS AND METHODS: Adults with obesity were classified per Morningness-Eveningness Questionnaire (MEQ) as either MORN (n = 27, 22 female, MEQ = 63.7 ± 4.7, 53.8 ± 6.7 years, 35.3 ± 4.9 kg/m2) or INT (n = 29, 23 female, MEQ = 48.8 ± 6.7, 56.6 ± 9.0 years, 35.7 ± 6.1 kg/m2). A 120 min euglycaemic-hyperinsulinaemic clamp (40 mU/m2/min, 90 mg/dl) was conducted to assess macrovascular insulin sensitivity via brachial artery flow-mediated dilation (%FMD; conduit artery), post-ischaemic flow velocity (resistance arteriole), as well as microvascular insulin sensitivity via contrast-enhanced ultrasound [e.g. microvascular blood volume (perfusion)]. Fasting plasma arginine and citrulline, as well as fasting and clamp-derived plasma endothelin-1 and nitrate/nitrite, were assessed as surrogates of vasoconstriction and nitric oxide-mediated vasodilation. Aerobic fitness (VO2max) and body composition (dual-energy X-ray absorptiometry) were also collected. RESULTS: MORN had a higher VO2max compared with INT (p < .01), although there was no difference in fat mass. While fasting FMD was similar between groups, insulin lowered FMD corrected to shear stress and microvascular blood volume in INT compared with MORN after co-varying for VO2max (both p ≤ .02). INT also had a lower fasting nitrate (p = .03) and arginine (p = .07). Higher MEQ correlated with elevated FMD (r = 0.33, p = .03) and lower post-ischaemic flow velocity (r = -0.33, p = .03) as well as shear rate (r = -0.36, p = .02) at 120 min. CONCLUSION: When measured during the morning, INT had a lower vascular insulin sensitivity than MORN. Additional work is needed to understand endothelial function differences among chronotypes to optimize cardiovascular disease risk reduction.

Does perceived caloric and nutrient intake influence the acute effect of beverage consumption on cardiovascular function?

Our objective was to explore whether consuming the same high-fat/sugar beverage affects endothelial function differently depending on whether it is presented as "unhealthy" [accurate high calorie (kcal), fat, and sugar information displayed] versus "healthy" (inaccurate low kcal, fat, and sugar information displayed). Twenty-five, young (21 ± 2 yr), healthy, food-stress/shame-prone women completed three conditions: milkshake consumption (540 kcal, 80 g sugar, and 14 g fat) where correct, "unhealthy" nutritional information was shown to participants (milkshake condition), consumption of the same milkshake but with incorrect, "healthy" information shown to participants (100 kcal, 3 g sugar, and 4 g fat; sham-nutrishake condition), and water consumption (control condition). Pre- and postbeverage we assessed 1) endothelial function via standard brachial artery flow-mediated dilation (FMD); 2) perceived shame, stress, beverage healthiness, and harm; and 3) blood (plasma) glucose, insulin, triglycerides and oral fluid cortisol, and tumor necrosis factor-alpha (TNFα) receptor binding. Glucose, triglycerides, and insulin increased in the milkshake and sham-nutrishake conditions (P < 0.05). The milkshake was perceived as less healthy (P < 0.001) and more harmful (P < 0.001) than the sham-nutrishake. Shame, stress, oral fluid cortisol and TNFα receptor binding did not increase postconsumption. FMD decreased after the milkshake condition (pre: 7.4 ± 3.3%; post-60 min: 4.9 ± 2.9%; post-90 min: 4.5 ± 3.1%, P < 0.001) but not the sham-nutrishake (pre: 5.7 ± 2.2%; post-60 min: 5.5 ± 2.6%; post-90 min: 5.0 ± 2.4%, P = 0.43) or control conditions (pre: 7.0 ± 2.6%; post-60 min: 6.6 ± 4.1%; post-90 min: 6.0 ± 3.2%, P = 0.29). Shear rate stimulus covariation did not alter FMD results. Lower perceived beverage healthiness was significantly associated with a greater reduction in FMD (ρ = 0.36, P = 0.002). In conclusion, a high-fat/sugar milkshake reduced FMD only when presented as high in fat, sugar, and calories. This suggests that perceptions about nutritional information contribute to the impact of food intake on endothelial function and that nocebo effects could be involved in cardiovascular disease etiology.NEW & NOTEWORTHY This was the first study to investigate how perceived nutritional content influences the impact of a high-sugar/fat beverage on endothelial function. We found that a high-sugar/fat beverage only reduced endothelial function when it was presented to participants as high in calories, fat, and sugar. This suggests that perceived nutritional information contributes to the impact of high sugar and fat intake on endothelial function.

A novel wire-guided prefenestration technique for patients with type B aortic dissection: A case report.

RATIONALE: Acute type B aortic dissection (ABAD) is a fatal and severe cardiovascular disease. There are various strategies for dissection involving the left subclavian artery, but limited by the variety and cost of stents, the treatment brings certain obstacles. The aim of this study is to evaluate the effectiveness and safety of the wire-guided prefenestration technique for treating left subclavian artery involvement in patients with arterial dissection. PATIENT CONCERNS: A 48-year-old man was transferred to our hospital due to persistent chest and back pain that had lasted for 6 hours. DIAGNOSES: Preoperative computed tomography angiogram (CTA) of the thoracic and abdominal aorta diagnosed with ABAD that affected his left subclavian artery, who needed emergency endovascular treatment due to malperfusion of the lower limb arteries. INTERVENTIONS: To perform the procedure, a guide wire was inserted through the left brachial artery, exited through the right femoral artery, and then entered the pre-fenestrated hole leading to the main stent. The stent was released while the guide wire was in position, and the left subclavian artery was reconstructed using viabahn. OUTCOMES: Thoracic endovascular aortic repair was successfully completed for ABAD. A follow-up CT angiogram of the thoracic and abdominal aorta revealed positive vascular remodeling and no signs of significant internal leakage after one month. LESSONS: This innovative approach offers a secure and efficient treatment option for aortic dissection in individuals who have undergone left subclavian artery reconstruction.

The vascular response to acute sauna heating is similar in young and middle-aged adults.

Sauna has been linked to a reduction of cardiovascular disease risk and is a promising nonpharmacological treatment for populations at risk of cardiovascular disease. This study examined the vascular response to an acute bout of sauna heating in young and middle-aged individuals. Ten young (25 ± 4 yr, 6 males and 4 females) and eight middle-aged adults (56 ± 4 yr, 4 males and 4 females) underwent 40 min of sauna exposure at 80°C. Esophageal and intramuscular temperatures, brachial and superficial femoral artery blood flow, artery diameter, and shear rates were recorded at baseline and following heat exposure. Brachial artery flow-mediated dilation (FMD) was measured at baseline and following 90 min of recovery. Esophageal and muscle temperatures increased similarly in the young and middle-aged adults by 1.5 ± 0.53 and 1.95 ± 0.70°C, respectively (P < 0.05). The shear rate increased by 170-200% (P < 0.001), while blood flow increased by 180-390% (P < 0.001) in the superficial femoral and brachial arteries, respectively, and did not differ between age groups (P = 0.190-0.899). Systolic blood pressure was reduced from 135 ± 17 to 122 ± 20 mmHg (P = 0.017) in middle-aged participants. These data indicate that young and middle-aged adults have similar vascular responses to acute sauna heating.NEW & NOTEWORTHY Sauna therapy has been shown to improve cardiovascular health and function in older adults and individuals with cardiovascular disease risk factors. Specifically, improvements in vascular function have been reported and have been attributed to the increased hemodynamic stimuli on the vasculature associated with thermal stress. The present study quantified this hemodynamic response to a sauna protocol associated with improved cardiovascular health across the lifespan. Our data show that middle-aged adults have the same shear rate and blood flow response to sauna as young adults.

Optimization and validation of a suprasystolic brachial cuff-based method for noninvasively estimating central aortic blood pressure.

Clinical studies have extensively demonstrated that central aortic blood pressure (CABP) has greater clinical significance in comparison with peripheral blood pressure. Despite the existence of various techniques for noninvasively measuring CABP, the clinical applications of most techniques are hampered by the unsatisfactory accuracy or large variability in measurement errors. In this study, we proposed a new method for noninvasively estimating CABP with improved accuracy and reduced uncertain errors. The main idea was to optimize the estimation of the pulse wave transit time from the aorta to the occluded lumen of the brachial artery under a suprasystolic cuff by identifying and utilizing the characteristic information of the cuff oscillation wave, thereby improving the accuracy and stability of the CABP estimation algorithms under various physiological conditions. The method was firstly developed and verified based on large-scale virtual subject data (n = 800) generated by a computational model of the cardiovascular system coupled to a brachial cuff, and then validated with small-scale in vivo data (n = 34). The estimation errors for the aortic systolic pressure were -0.05 ± 0.63 mmHg in the test group of the virtual subjects and -1.09 ± 3.70 mmHg in the test group of the patients, both demonstrating a good performance. In particular, the estimation errors were found to be insensitive to variations in hemodynamic conditions and cardiovascular properties, manifesting the high robustness of the method. The method may have promising clinical applicability, although further validation studies with larger-scale clinical data remain necessary.

Elevated blood flow in people with type 1 and type 2 diabetes.

AIMS: The study aimed to evaluate blood flow (BF) and microvascular function in the forearm of people with type 1 and type 2 diabetes at rest and after ischemia. Microvascular function plays a crucial role in regulating BF in peripheral tissues based on metabolic demand. METHODS: People with diabetes and sex-matched healthy controls were recruited. Brachial artery diameter and blood velocity were continuously measured at rest and after ischemia by an automatic tracking system. BF and vascular conductance were then calculated. RESULTS: Forty-nine people with diabetes and 49 controls were enrolled. BF at rest and after ischemia was significantly higher in people with diabetes than controls: Type 1, 243 ± 116 and 631 ± 233 ml/min; controls, 180 ± 106 and 486 ± 227 ml/min; Type 2, 332 ± 149 and 875 ± 293 ml/min; controls 222 ± 106 and 514 ± 224 ml/min. Vascular conductance was significantly higher in Type 2 than in controls at rest and after ischemia. CONCLUSIONS: People with diabetes exhibited significantly increased BF, with Type 2 also showing heightened vascular conductance. Activating metabolic pathways triggered by hyperglycemia may lead to distinct vascular redistribution, potentially impairing blood flow over time. These findings of the study underscore the importance of understanding overall vascular dynamics in diabetes and its implications for vascular health.

Single and 7-day handgrip and squat exercise prevents endothelial ischemia-reperfusion injury in individuals with cardiovascular disease risk factors.

Whole body exercise provides protection against endothelial ischemia-reperfusion (IR) injury. In this crossover study, we examined the effects of 1) single bout of local exercise (handgrip, squats) on endothelial responses to IR, and 2) if 7 days of daily local exercise bolsters these effects in individuals with cardiovascular disease (CVD) risk factors. Fifteen participants (9 women, 58 ± 5 yr, ≥2 CVD risk factors) attended the laboratory for six visits. Subsequent to familiarization (visit 1), during visit 2 (control) brachial artery flow-mediated dilation (FMD) was measured before and after IR (15-min upper-arm ischemia, 15-min reperfusion). One week later, participants were randomized to 4 × 5-min unilateral handgrip (50% maximal voluntary contraction, 25 rpm) or squat exercises (15 rpm), followed by IR plus FMD measurements. Subsequently, home-based exercise was performed (6 days), followed by another visit to the laboratory for the IR protocol plus FMD measurements (18-24 h after the last exercise bout). After a 2-wk washout period, procedures were repeated with the alternative exercise mode. For a single exercise bout, we found a significant IR injury × exercise mode interaction (P < 0.01) but no main effect of injury (P = 0.08) or condition (P = 0.61). A lower post-IR FMD was evident after control (pre-IR: 4.3 ± 2.1% to post-IR: 2.9 ± 1.9%, P < 0.01) but not after handgrip (pre-IR: 3.8 ± 1.6% to post-IR: 3.4 ± 1.5%, P = 0.31) or squats (pre-IR: 3.9 ± 1.8% to post-IR: 4.0 ± 1.9%, P = 0.74). After 7 days of daily exercise, we found no change in FMD post-IR following handgrip (pre-IR: 4.3 ± 1.9% to post-IR: 4.7 ± 3.2%) or squats (pre-IR: 3.7 ± 2.1% to post-IR: 4.7 ± 3.0%, P > 0.05). Single bouts of dynamic, local exercise (handgrip, squats) provide remote protection against endothelial IR-induced injury in individuals with CVD risk factors, with 1-wk daily, home-based exercise preserving these effects for up to 24 h following the last exercise bout.NEW & NOTEWORTHY We show that single bouts of dynamic handgrip and squat exercise provide remote protection against endothelial ischemia-reperfusion (IR)-induced injury in individuals with cardiovascular disease (CVD) risk factors, with 1-wk daily, home-based exercise preserving these effects for up to 24 h following the last exercise bout.

Omega-3 fatty acids and endothelial function: A GRADE-assessed systematic review and meta-analysis.

INTRODUCTION: N-3 polyunsaturated fatty acids (PUFAs) supplementation has been reported to have an impact on flow-mediated dilatation (FMD), a conventionally used clinical technique for estimating endothelial dysfunction. However, its proven effects on endothelial function are unclear. This systematic review and meta-analysis were conducted to evaluate the effects of n-3 PUFAs supplementation on FMD of the brachial artery. METHOD: This study was performed following the PRISMA guidelines. To identify eligible RCTs, a systematic search was completed in PubMed/Medline, Scopus and Web of Science using relevant keywords. A fixed- or random-effects model was utilized to estimate the weighted mean difference (WMD) and 95% confidence interval (95% CI). RESULTS: Thirty-two studies (with 35 arms) were included in this meta-analysis, involving 2385 subjects with intervention duration ranging from 4 to 48 weeks. The pooled meta-analysis demonstrated a significant effect of omega-3 on FMD (WMD = 0.8%, 95% CI = 0.3-1.3, p = .001) and heterogeneity was significant (I2 = 82.5%, p < .001). CONCLUSION: We found that n-3 PUFA supplementation improves endothelial function as estimated by flow-mediated dilatation of the brachial artery.