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Background: The elevated blood pressure (BP) and lower cardiac autonomic modulation (CAM) are associated with higher morbidity mortality risk among older adults. Although exercise is an important intervention for cardiovascular promotion, it is unclear whether combat sports training could benefit cardiovascular outcomes as much as autonomic in this population. This study compared the effects of 12 weeks of Muay Thai (MT) training against functional training (FT) on CAM and hemodynamic parameters in older adults., Methods: The sample consisted of 50 older adults (41 women; 66.0 ± 5.3 years old), who were equaly randomized into FT (n = 25) and MT (n = 25) intervention groups. CAM was measured by 30-min rest heart rate variability. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and resting heart rate (RHR) were measured using an automatic oscillometric device. Pulse pressure (PP) and the double product (DP) were also calculated. The interventions were carried out three times a week, with 60-min length per session, during 12 consecutive weeks. The intensity of the interventions was measured using the subjective perception of exertion scale and by accelerometer. Two-factor repeated measures analysis of covariance was used for groups comparison, considering intervention group and body mass as factors. The 95% confidence interval of the difference (95%CIdif) was also calculated and the effect size was measured using partial eta squared (η 2 p )., Results: CAM indices did not show significant changes across moments and intervention groups. In hemodynamic parameters, only in DBP was there an effect of the moment (F 1,39  = 8.206; P = 0.007; η 2 p  = 0.174, large) and interaction effect between group*moment (F 1,39  = 7.950; P = 0.008; η 2 p  = 0.169, large). Specifically, the MT group at the post-training moment showed lower DBP (P = 0.010; 95%CI dif  = -13.3; -1.89) in relation to the FT group. Furthermore, the MT group showed a decrease in DBP during training (P = 0.002; 95%CI dif  = -10.3; -2.6). Also, an increase in training intensity was also found over the 12 weeks in FT, with no difference between the groups., Conclusion: After 12 weeks of MT practice there was a reduction in DBP compared to FT in older adults., Trial Registration: NCT03919968 Registration date: 01/02/2019., (© 2024. The Author(s).)

Radial applanation tonometry is a well-established technique for hemodynamic monitoring and is becoming popular in affordable non-invasive wearable healthcare electronics. To assess the central aortic pressure using radial-based measurements, there is an essential need to develop mathematical approaches to estimate the central pressure waveform. In this study, we propose a new Fourier-based machine learning (F-ML) methodology to transfer non-invasive radial pressure measurements to the central pressure waveform. To test the method, collection of tonometry recordings of the radial and carotid pressure measurements are used from the Framingham Heart Study (2640 individuals, 55 % women) with mean (range) age of 66 (40-91) years. Method-derived estimates are significantly correlated with the measured ones for three major features of the pressure waveform (systolic blood pressure, r=0.97, p < 0.001; diastolic blood pressure, r=0.99, p < 0.001; and mean blood pressure, r=0.99, p < 0.001). In all cases, the Bland-Altman analysis shows negligible bias in the estimations and error is bounded to 5.4 mmHg. Findings also suggest that the F-ML approach reconstructs the shape of the central pressure waveform accurately with the average normalized root mean square error of 5.5 % in the testing population which is blinded to all stages of machine learning development. The results show that the F-ML transfer function outperforms the conventional generalized transfer function, particularly in terms of reconstructing the shape of the central pressure waveform morphology. The proposed F-ML transfer function can provide accurate estimates for the central pressure waveform, and ultimately expand the usage of non-invasive devices for central hemodynamic assessment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hemodynamic assessment of patients with pulmonary embolism (PE) remains a fundamental component of early risk stratification that in turn, influences subsequent monitoring and therapeutic strategies. The current body of literature and international evidence-based clinical practice guidelines focus mainly on the use of systolic blood pressure (SBP). The accuracy of this single hemodynamic parameter, however, and its optimal values for the identification of hemodynamic instability have been recently questioned by clinicians. For example, abnormal SBP or shock index may be a late indicator of adverse outcomes, signaling a patient in whom the cascade of hemodynamic compromise is already well underway. The aim of the present article is to review the current evidence supporting the use of SBP and analyze the potential integration of other parameters to assess the hemodynamic stability, impending clinical deterioration, and guide the reperfusion treatment in patients with PE, as well as to suggest potential strategies to further investigate this issue., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Context: Energy drinks (EDs) are beverages that contain ingredients that may pose a risk to consumers' cardiovascular health. But current evidence is conflicting and warrants further investigation., Objective: A systematic review and meta-analysis was conducted on studies that examined the acute effects of ED consumption on systolic blood pressure (SBP), diastolic blood pressure (DBP), resting heart rate, cardiac output (CO), endothelial function, and QT/QTc interval in healthy adults., Data Sources: The databases PubMed, EMBASE, Cochrane, LILACS, Web of Science, SportDiscus, and the gray literature were searched to identify randomized controlled trials (RCTs)., Data Extraction: Two independent evaluators screened 2014 studies and extracted relevant data from those selected for the analysis. A risk of bias assessment was also performed with the RoB 2 tool and a strength of evidence assessment was performed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE)., Data Analysis: A total of 17 RCTs were included in the meta-analysis. With regard to risk of bias, 11 studies were rated as having "some concerns" and 6 as "high risk of bias." The consumption of EDs increased SBP, DBP, and CO in different time frames. More pronounced effects were seen on SBP at 60-80 minutes (4.71 mmHg; 95% CI: 2.97-6.45; GRADE: moderate), DBP at 120 minutes (4.51 mmHg; 95% CI: 2.60-6.42; GRADE: low), and CO at 30-40 minutes after consumption (0.43 L; 95% CI: 0.08-0.77; GRADE: very low). The effects of ED consumption on resting heart rate and QT/QTc interval were not significant (P ≤ 0.05). The assessment of endothelial function effects was not performed due to the absence of any RCTs meeting the inclusion criteria., Conclusions: Acute consumption of EDs increases SBP, DBP, and CO in healthy adults. However, no alterations were observed in other cardiovascular parameters. The results should be interpreted with caution due to the limited number of studies included in the analysis., Systematic Review Registration: PROSPERO registration no. CRD42022295335., (© The Author(s) 2023. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study was conducted to investigate the systemic hemodynamic and vascular changes in women during and after two commonly used clinical blood flow restriction (BFR) pressures at rest. There are minimal data regarding the independent effects of BFR on hemodynamic and systemic vascular changes due to pressor response, particularly among women. Therefore, this study investigated BFR-induced alterations in pressor response and systemic flow redistribution at rest during two commonly used pressures (50% and 80% limb occlusion pressure [LOP]). Fifteen women (22.1 ± 4.2 years) completed two randomised sessions involving 8-min of bilateral, lower limb restriction at 50% or 80% LOP followed by 8-min of recovery post-deflation. Changes in vascular (arterial diameter [DIA], time-averaged mean velocity [TAMV], volume flow [VF], and area) and hemodynamic (heart rate [HR] and blood pressure) measures over time (pre-, during, post-occlusion) and by session (50% vs. 80% LOP) were tested using repeated measures analysis of variance. Repeated measures correlations (r rm ) quantified common intraindividual associations between BFR-induced hemodynamic and vascular responses. HR increased from baseline during 50% LOP and remained elevated during recovery (p < 0.05). HR increased from baseline during 80% LOP, while tibial VF and TAMV decreased (p < 0.03 for all). HR and TAMV values returned to baseline during recovery, while brachial artery VF decreased (p < 0.05). Changes in HR, brachial VF, and brachial TAMV were similar between 50% and 80% LOP (r rm  = 0.32-0.70, p < 0.05 for all). At 80% LOP, changes in HR were positively correlated with brachial VF (r rm  = 0.38) and TAMV (r rm  = 0.43) and negatively correlated with tibial VF (r rm  = -0.36) and TAMV (r rm  = -0.30) (p < 0.05 for all). Results suggest that BFR at 80% LOP elicits an acute systemic pressor reflex without concomitant increases in brachial arterial flow, while 50% LOP elicits a subdued response., (© 2024 Scandinavian Society of Clinical Physiology and Nuclear Medicine.)

Objectives: Hemodynamic gain index (HGI), a novel hemodynamic index obtained from cardiopulmonary exercise testing (CPX), is associated with adverse cardiovascular outcomes. However, its specific relationship with ventricular arrhythmias (VAs) is unknown. We aimed to assess the association of HGI with risk of VAs in a prospective study. Design: Hemodynamic gain index was estimated using heart rate and systolic blood pressure (SBP) responses ascertained in 1945 men aged 42-61 years during CPX from rest to maximum exercise, using the formula: [(Heart rate max x SBP max ) - (Heart rate rest x SBP rest )]/(Heart rate rest x SBP rest ). Cardiorespiratory fitness (CRF) was measured using respiratory gas exchange analysis. Hazard ratios (HRs) (95% confidence intervals, CIs) were estimated for VAs. Results: Over a median follow-up duration of 28.2 years, 75 cases of VA were recorded. In analysis adjusted for established risk factors, a unit (bpm/mmHg) higher HGI was associated with a decreased risk of VA (HR 0.72, 95% CI: 0.55-0.95). The results remained consistent on adjustment for lifestyle factors and comorbidities (HR 0.72, 95% CI: 0.55-0.93). Comparing the top versus bottom tertiles of HGI, the corresponding adjusted HRs (95% CIs) were 0.51 (0.27-0.96) and 0.52 (0.28-0.94), respectively. The associations were attenuated on addition of CRF to the model. HGI improved risk discrimination beyond established risk factors but not CRF. Conclusions: Higher HGI is associated with a reduced risk of VAs in middle-aged and older Caucasian men, but dependent on CRF levels. Furthermore, HGI improves the prediction of the long-term risk for VAs beyond established risk factors but not CRF.

The cold pressor test (CPT) involves cold water immersion of either the upper or lower limb(s) and elicits increases in sympathetic nervous activity (SNA), heart rate (HR), and mean arterial pressure (MAP) via stimulation of pain and cutaneous thermoreceptors. Greater pain perception during the CPT is associated with greater increases in SNA and more robust physiological responses. Due to potential differential sensitivity to both painful and thermal stimuli between upper and lower limbs, as well as potential effects of total exposure area, it is unclear whether the choice of limb(s) in CPT protocol design differentially affects systemic and cerebral hemodynamic responses. Our objective was to assess systemic and cerebral hemodynamic and ventilatory responses to different CPT protocols of the hand (CPT H ), foot (CPT F ), or bilateral feet (CPT BF ). We hypothesized CPT BF would elicit greatest physiological responses due to increased exposure area to the cold stimulus. Twenty-eight (14 M, 14 F) healthy young adults [23.4 (SD: 2.4) yr] participated in three 3-min CPT protocols during a single visit. Blood pressure, HR, middle cerebral artery blood velocity (MCAv) and cerebrovascular conductance index, and end-tidal carbon dioxide ([Formula: see text]) were averaged over the final 30 s of each minute of the CPT for each protocol, and perceived pain was recorded at the end of each minute of the CPT. We found significant effects of the time-CPT protocol interaction on systolic blood pressure ( P = 0.02), diastolic blood pressure ( P < 0.01), MAP ( P < 0.01), and HR ( P < 0.001). There were no differences between CPT protocols on either MCAv ( P = 0.4) or cerebrovascular conductance index ( P = 0.1). HR responses peaked in the first minute of the CPT, and changes from baseline were greater in CPT BF [Δ14(16) beats/min] compared with CPT H [Δ5(13) beats/min; P = 0.01] and CPT F [Δ4.04(13.3) beats/min; P = 0.02]. MAP responses peaked in minute 2 of the CPT, and changes from baseline were greater in CPT H [Δ12(8) mmHg) and CPT BF (Δ13(9) mmHg] compared with CPT F [Δ8(7) mmHg; P < 0.01]. Perceived pain was significantly greater in the CPT BF [CPT1 7(2.3), CPT2 6.5(2.3), CPT3 6(3)] condition compared with CPT H [CPT1 6(1.3), CPT2 6(2.3), CPT3 6(2.3)] and CPT F [CPT1 6(3.0), CPT2 6(2.0), CPT3 5.5(3.0)] protocols at all three stages of the CPT ( P ≤ 0.01). Our findings suggest choice of limb(s) in CPT protocols may lead to differences in systemic hemodynamic responses, with pain perception potentially influencing these responses. Based on our results, we suggest that choice of limb should be considered in future design of CPT studies, with hand CPT providing the best balance between participant tolerability and robust physiological responses. NEW & NOTEWORTHY Choice of limb(s) in cold pressor test (CPT) studies appears to influence systemic hemodynamics. Hand and bilateral feet induce more robust responses than single-foot CPT, potentially due to increased exposure area and pain perception. Despite no significant cerebrovascular effects, a sustained hyperventilatory response was noted in bilateral feet CPT. Hand CPTs may provide a balance between robust physiological responses and tolerability. These findings underscore the need for careful limb selection in future CPT studies.

Background: Cuff blood pressure (BP) is recommended for guiding hypertension management. However, central BP has been proposed as a superior clinical measurement. This study aimed to determine whether controlling hypertension as measured by central BP was beneficial in reducing left ventricular mass index beyond control of standard cuff hypertension., Methods: This multicenter, open-label, blinded-end point trial was conducted in individuals treated for uncomplicated hypertension with controlled cuff BP (<140/90 mm Hg) but elevated central BP (≥0.5 SD above age- and sex-specific normal values). Participants were randomized to 24-months intervention with spironolactone 25 mg/day (n=148) or usual care control (n=153). The primary outcome was change in left ventricular mass index measured by cardiac MRI. Cuff and central BPs were measured by clinic, 7-day home and 24-hour ambulatory BPs., Results: At 24-months, there was a greater reduction in left ventricular mass index (-3.2 [95% CI, -5.0 to -1.3] g/m 2 ; P =0.001) with intervention compared with control. Cuff and central BPs were lowered by a similar magnitude across all BP measurement modes (eg, clinic cuff systolic BP, -6.16 [-9.60 to -2.72] mm Hg and clinic central systolic BP, -4.96 [-8.06 to -1.86] mm Hg; P ≥0.48 all). Secondary analyses found that changes in left ventricular mass index correlated to changes in BP, with the magnitude of effect nearly identical for BP measured by cuff (eg, 24-hour systolic BP, β, 0.17 [0.02-0.31] g/m 2 ) or centrally (24-hour systolic BP, β, 0.16 [0.01-0.32] g/m 2 )., Conclusions: Among individuals with central hypertension, spironolactone had beneficial effects in reducing LV mass. Secondary analyses showed that changes in LV mass were equally well associated with lower measured standard cuff BP and central BP., Registration: URL: https://www.anzctr.org.au/; Unique identifier: ACTRN12613000053729., Competing Interests: Disclosures J.E. Sharman is principal investigator of a National Health and Medical Research Council of Australia partnership grant (S0026615) that includes a medical technology company that manufactures a central blood pressure (BP) device, not referred to in this article. He has no personal financial conflicts relating to BP technology. S. Stewart is supported by a National Health and Medical Research Council of Australia Fellowship (GNT 1135894). The other authors report no conflicts.

Objective: Given the scarcity of studies analyzing the clinical predictors of pediatric septic cases that would progress to septic shock, this study aimed to determine strong predictors for pediatric emergency department (PED) patients with sepsis at risk for septic shock and mortality., Methods: We conducted chart reviews of patients with ≥ 2 age-adjusted quick Sequential Organ Failure Assessment score (qSOFA) criteria to recognize patients with an infectious disease in two tertiary PEDs between January 1, 2021, and April 30, 2022. The age range of included patients was 1 month to 18 years. The primary outcome was development of septic shock within 48 h of PED attendance. The secondary outcome was sepsis-related 28-day mortality. Initial important variables in the PED and hemodynamics with the highest and lowest values during the first 24 h of admission were also analyzed., Results: Overall, 417 patients were admitted because of sepsis and met the eligibility criteria for the study. Forty-nine cases progressed to septic shock within 48 h after admission and 368 were discharged without progression. General demographics, laboratory data, and hemodynamics were analyzed by multivariate analysis. Only the minimum diastolic blood pressure/systolic blood pressure ratio (D/S ratio) during the first 24 h after admission remained as an independent predictor of progression to septic shock and 28-day mortality. The best cutoff values of the D/S ratio for predicting septic shock and 28-day mortality were 0.52 and 0.47, respectively., Conclusions: The D/S ratio is a practical bedside scoring system in the PED and had good discriminative ability in predicting the progression of septic shock and in-hospital mortality in PED patients. Further validation is essential in other settings., (© 2024. The Author(s).)

Background: Septic shock is the progression of sepsis, defined as cardiovascular dysfunction during systemic infection, and it has a mortality rate of 40 %-80 %. Loss of vascular tone is an important pathophysiological feature of septic shock. Diastolic blood pressure (DBP) was reported to be associated with vascular tone. This study aimed to identify the associations of several hemodynamic indices, especially DBP, with outcome in pediatric septic shock to allow for timely interventions., Methods: Children with persistent catecholamine-resistant shock had a pulse index continuous cardiac output (PiCCO®) system implanted for invasive hemodynamic monitoring and were enrolled in the current study. Serial cardiac index, systemic vascular resistance index (SVRI), systolic blood pressure (SBP), mean arterial pressure (MAP), and DBP were recorded during the first 24 h following PiCCO® initiation. All hemodynamic parameters associated with 28-day mortality were further analyzed using receiver operating characteristic curve analysis., Results: Thirty-three children with persistent catecholamine-resistant shock were enrolled. The median age was 12 years and the youngest children were 5 years old. Univariate analysis noted that SVRI, SBP, MAP, and DBP were significantly higher, and shock index was significant lower, in survivors compared with non-survivors (p < 0.05). In the multivariate analysis, only SVRI and DBP remained independent predictors of 28-day mortality. DBP had the best correlation with SVRI (r = 0.718, n = 219, p < 0.001). The area under the receiver operating characteristic curves of SVRI and DBP for predicting 28-day mortality during the first 24 h of persistent catecholamine-resistant shock were >0.75, indicating a good prediction for mortality., Conclusions: DBP correlated well with SVRI and it can serve as a predictor for mortality in pediatric septic shock. Furthermore, DBP was a superior discriminator of mortality when compared with SBP and MAP. A lower DBP was an independent hemodynamic factor associated with 28-day mortality., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Taiwan Pediatric Association. Published by Elsevier B.V. All rights reserved.)

Purpose: We determined the effect of habitual endurance exercise and age on aortic pulse wave velocity (aPWV), augmentation pressure (AP) and systolic blood pressure (aSBP), with statistical adjustments of aPWV and AP for heart rate and aortic mean arterial pressure, when appropriate. Furthermore, we assessed whether muscle sympathetic nerve activity (MSNA) correlates with AP in young and middle-aged men., Methods: Aortic PWV, AP, aortic blood pressure (applanation tonometry; SphygmoCor) and MSNA (peroneal microneurography) were recorded in 46 normotensive men who were either young or middle-aged and endurance-trained runners or recreationally active nonrunners (10 nonrunners and 13 runners within each age-group). Between-group differences and relationships between variables were assessed via ANOVA/ANCOVA and Pearson product-moment correlation coefficients, respectively., Results: Adjusted aPWV and adjusted AP were similar between runners and nonrunners in both age groups (all, P > 0.05), but higher with age (all, P < 0.001), with a greater effect size for the age-related difference in AP in runners (Hedges' g, 3.6 vs 2.6). aSBP was lower in young (P = 0.009; g = 2.6), but not middle-aged (P = 0.341; g = 1.1), runners compared to nonrunners. MSNA burst frequency did not correlate with AP in either age group (young: r = 0.00, P = 0.994; middle-aged: r = - 0.11, P = 0.604)., Conclusion: There is an age-dependent effect of habitual exercise on aortic haemodynamics, with lower aSBP in young runners compared to nonrunners only. Statistical adjustment of aPWV and AP markedly influenced the outcomes of this study, highlighting the importance of performing these analyses. Further, peripheral sympathetic vasomotor outflow and AP were not correlated in young or middle-aged normotensive men., (© 2022. The Author(s).)

Several limitations regarding pulse pressure variation (PPV) use have been reported. Our aim was to describe changes in the PPV operative performance as a predictor of fluid responsiveness during the development of a swine endotoxin shock model and to assess hemodynamic variables associated with PPV changes. A swine porcine endotoxin shock model was established (Escherichia Coli 055:B5 endotoxin) in 7 pigs, and 3 pigs were included in the control group. The endotoxin was infused until the mean arterial pressure (MAP) dropped below 50 mmHg (TH0); then, the model animal was reanimated with fluids and vasopressors. We performed fluid challenges every hour for 6 h. ROC curve analysis and a linear mixed model were performed. The area under the curve of PPV decreased from 0.95 (0.81-1.00) to 0.60 (0.17-1.00) at TH0. Its cutoff increased from 10.5 to 22.00% at TH0. PPV showed an inverse relationship with stroke volume, mean systemic filling pressure, MAP, and systemic vascular resistance (SVR) (p < 0.001, AIC = 111.85). The PPV operative performance as a predictor of fluid responsiveness decreased with the progression of shock. This could lead to an inverse association between PPV and the following variables: MAP and SVR., (© 2022. The Author(s).)

Background: Arterial compliance assists the cardiovascular system with three key roles: (i) storing up to 50% of the stroke volume; (ii) ensuring blood flow during diastole; (iii) dampening pressure oscillations through arterial distension. In mock circulation loops (MCLs), arterial compliance was simulated either with membrane, spring, or Windkessel chambers. Although they have been shown to be suitable for cardiac device testing, their passive behavior can limit stress-based testing of arteries. Here we present an active compliance chamber with a feedback control of variable compliance as part of an MCL designed for biomechanical evaluation of arteries under physiological waveforms., Materials and Methods: The chamber encloses a piston that changes the volume via a cascaded controller when there is a difference between the real-time pressure and the physiological reference pressure with the aim to equilibrate both pressures., Results: The experimental results showed repeatable physiological waveforms of aortic pressure in health (80-120 mm Hg), systemic hypertension (90-153 mm Hg), and heart failure reduced ejection fraction (78-108 mm Hg). Statistical validation (n = 20) of the function of the chamber is presented against compared raw data., Conclusion: We demonstrate that the active compliance chamber can track the actual pressure of the MCL and balance it in real time (every millisecond) with the reference values in order to shape the given pressure waveform. The active compliance chamber is an advanced tool for MCL applications for biomechanical examination of stented arteries and for preclinical evaluation of vascular implants., (© 2021 The Authors. Artificial Organs published by International Center for Artificial Organ and Transplantation (ICAOT) and Wiley Periodicals LLC.)

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Background: Hemodynamic disturbances cause half of the perioperative strokes following carotid endarterectomy (CEA). Guidelines strongly recommend strict pre- and postoperative blood pressure (BP) monitoring in CEA patients, but do not provide firm practical recommendations. Although in the Netherlands 50 centres perform CEA, no national protocol on perioperative hemodynamic, and cerebral monitoring exists. To assess current monitoring policies of all Dutch CEA-centres, a national survey was conducted., Methods: Between May and July 2017 all 50 Dutch CEA-centres were invited to complete a 42-question survey addressing perioperative hemodynamic and cerebral monitoring during CEA. Nonresponders received a reminder after 1 and 2 months. By November 2017 the survey was completed by all centres., Results: Preoperative baseline BP was based on a single bilateral BP-measurement at the outpatient-clinic in the majority of centres (n = 28). In 43 centres (86%) pre-operative monitoring (transcranial Doppler (TCD, n = 6), electroencephalography (EEG, n = 11), or TCD + EEG (n = 26)) was performed as a baseline reference. Intraoperatively, large diversity for type of anaesthesia (general: 45 vs. local [LA]:5) and target systolic BP (>100 mm hg - 160 mm hg [n = 12], based on preoperative outpatient-clinic or admission BP [n = 18], other [n = 20]) was reported. Intraoperative cerebral monitoring included EEG + TCD (n = 28), EEG alone (n = 13), clinical neurological examination with LA (n = 5), near-infrared spectroscopy with stump pressure (n = 1), and none due to standard shunting (n = 3). Postoperatively, significant variation was reported in standard duration of admission at a recovery or high-care unit (range 3-48 hr, mean:12 hr), maximum accepted systolic BP (range >100 mm hg - 180 mm Hg [n = 32]), postoperative cerebral monitoring (standard TCD [n = 16], TCD on indication [n = 5] or none [n = 24]) and in timing of postoperative cerebral monitoring (range directly postoperative - 24 hr postoperative; median 3 hr)., Conclusions: In Dutch centres performing CEA the perioperative hemodynamic and cerebral monitoring policies are widely diverse. Diverse policies may theoretically lead to over- or under treatment. The results of this national audit may serve as the baseline dataset for development of a standardized and detailed (inter)national protocol on perioperative hemodynamic and cerebral monitoring during CEA., (Copyright © 2021. Published by Elsevier Inc.)

Background: Brachial systolic blood pressure (BP) is the most commonly used metric for monitoring hypertension. However, recent studies suggest that brachial systolic BP underestimates left ventricle (LV) systolic load in patients with coarctation of aorta (COA). Since brachial systolic BP is used as a surrogate of arterial afterload in clinical practice, it is important to determine how well it correlates with LV remodeling and stiffness in patients with COA as compared to patients with idiopathic hypertension., Methods: This is cross-sectional study of COA patients with hypertension (COA group) and adults with idiopathic hypertension (control group). Both groups were matched 1:1 based on age, sex, BMI and systolic BP. We hypothesized that the COA group will have higher LV systolic and diastolic stiffness, and more advanced left atrial remodeling and pulmonary hypertension. We assessed LV systolic stiffness using end-systolic elastance, and diastolic stiffness using LV stiffness constant and chamber capacitance (LV-end-diastolic volume at an end-diastolic pressure of 20mm Hg) RESULTS: There were 112 patients in each group. Although both groups had similar systolic BP, the COA group had a higher end-systolic elastance (2.37 ± 0.74 vs 2.11 ± 0.54 mm Hg/mL, P= .008), higher LV stiffness constant (6.91 ± 0.81 vs 5.93 ± 0.79, P= .006) and lower LV-end-diastolic volume at an end-diastolic pressure of 20mm Hg (58 ± 9 vs 67 ± 11 mL/m 2 , P< .001). Additionally, the COA group had more advanced left atrial remodeling and higher pulmonary artery pressures which is corroborating evidence of high LV filling pressure., Conclusions: COA patients have more LV stiffness and abnormal hemodynamics compared to non-COA patients with similar systolic BP, suggesting that systolic BP may underestimate LV systolic load in this population. Further studies are required to determine whether the observed LV stiffness and dysfunction translates to more cardiovascular events during follow-up, and whether adopting a stricter systolic BP target in clinical practice or changing threshold for COA intervention will lead to less LV stiffness and better clinical outcomes., (Copyright © 2021. Published by Elsevier Inc.)

Sedentary time has recently been included in the 24-h activity guidelines. However, the impact of habitual sedentary patterns on autonomic cardiovascular regulation are unclear. We tested the hypothesis that more sedentary time and fewer sedentary breaks were associated with lower cardiovagal baroreflex sensitivity. More frequent sedentary breaks, but not total sedentary time, was independently and positively associated with vagally mediated blood pressure control. Breaking up sedentary time could be more important than total sedentary time for cardiovascular health. Novelty: Breaks in sedentary time is an independent predictor of cardiovagal baroreflex sensitivity, with more frequent breaks associated with better vagally mediated blood pressure regulation.

We present a novel framework for investigating the role of vascular structure on arterial haemodynamics in large vessels, with a special focus on the human common carotid artery (CCA). The analysis is carried out by adopting a three-dimensional (3D) derived, fibre-reinforced, hyperelastic structural model, which is coupled with an axisymmetric, reduced order model describing blood flow. The vessel transmural pressure and lumen area are related via a Holzapfel-Ogden type of law, and the residual stresses along the thickness and length of the vessel are also accounted for. After a structural characterization of the adopted hyperelastic model, we investigate the link underlying the vascular wall response and blood-flow dynamics by comparing the proposed framework results against a popular tube law. The comparison shows that the behaviour of the model can be captured by the simpler linear surrogate only if a representative value of compliance is applied. Sobol's multi-variable sensitivity analysis is then carried out in order to identify the extent to which the structural parameters have an impact on the CCA haemodynamics. In this case, the local pulse wave velocity (PWV) is used as index for representing the arterial transmission capacity of blood pressure waveforms. The sensitivity analysis suggests that some geometrical factors, such as the stress-free inner radius and opening angle, play a major role on the system's haemodynamics. Subsequently, we quantified the differences in haemodynamic variables obtained from different virtual CCAs, tube laws and flow conditions. Although each artery presents a distinct vascular response, the differences obtained across different flow regimes are not significant. As expected, the linear tube law is unable to accurately capture all the haemodynamic features characterizing the current model. The findings from the sensitivity analysis are further confirmed by investigating the axial stretching effect on the CCA fluid dynamics. This factor does not seem to alter the pressure and flow waveforms. On the contrary, it is shown that, for an axially stretched vessel, the vascular wall exhibits an attenuation in absolute distension and an increase in circumferential stress, corroborating the findings of previous studies. This analysis shows that the new model offers a good balance between computational complexity and physics captured, making it an ideal framework for studies aiming to investigate the profound link between vascular mechanobiology and blood flow., (© 2021. The Author(s).)

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[Figure: see text].

Background: Elevated level of plasma uric acid (PUA) has been associated with cardiovascular disease, but whether uric acid is an independent risk factor or merely a marker remains controversial., Methods: We investigated in a cross-sectional setting the association of PUA with hemodynamics in 606 normotensive and never-medicated hypertensive subjects (295 men, 311 women, age range 19-73 years) without cardiovascular disease or gout. In all except 15 individuals, PUA was within the normal range. Supine hemodynamics were recorded using whole-body impedance cardiography and radial tonometric pulse wave analysis., Results: The mean concentrations of PUA in age, sex and body mass index adjusted quartiles were 234, 278, 314, and 373 µmol/l, respectively. The highest PUA quartile presented with higher aortic to popliteal pulse wave velocity (PWV) than the lowest quartile (8.7 vs. 8.2 m/s, p = 0.026) in analyses additionally adjusted for plasma concentrations of C-reactive protein, low density lipoprotein cholesterol, triglycerides, and mean aortic blood pressure. No differences in radial and aortic blood pressure, wave reflections, heart rate, cardiac output, and systemic vascular resistance were observed between the quartiles. In linear regression analysis, PUA was an independent explanatory factor for PWV (β = 0.168, p < 0.001, R 2 of the model 0.591), but not for systolic or diastolic blood pressure. When the regression analysis was performed separately for men and women, PUA was an independent predictor of PWV in both sexes., Conclusions: PUA concentration was independently and directly associated with large arterial stiffness in individuals without cardiovascular disease and PUA levels predominantly within the normal range. Trial registration ClinicalTrials.gov NCT01742702.

Background Increased potassium intake lowers blood pressure in patients with hypertension, but increased potassium intake also elevates plasma concentrations of the blood pressure-raising hormone aldosterone. Besides its well-described renal effects, aldosterone is also believed to have vascular effects, acting through mineralocorticoid receptors present in endothelial and vascular smooth muscle cells, although mineralocorticoid receptors-independent actions are also thought to be involved. Methods and Results To gain further insight into the effect of increased potassium intake and potassium-stimulated hyperaldosteronism on the human cardiovascular system, we conducted a randomized placebo-controlled double-blind crossover study in 25 healthy normotensive men, where 4 weeks treatment with a potassium supplement (90 mmol/day) was compared with 4 weeks on placebo. At the end of each treatment period, we measured potassium and aldosterone in plasma and performed an angiotensin II (AngII) infusion experiment, during which we assessed the aldosterone response in plasma. Hemodynamics were also monitored during the AngII infusion using ECG, impedance cardiography, finger plethysmography (blood pressure-monitoring), and Doppler ultrasound. The study showed that higher potassium intake increased plasma potassium (mean±SD, 4.3±0.2 versus 4.0±0.2 mmol/L; P =0.0002) and aldosterone (median [interquartile range], 440 [336-521] versus 237 [173-386] pmol/L; P <0.0001), and based on a linear mixed model for repeated measurements, increased potassium intake potentiated AngII-stimulated aldosterone secretion ( P =0.0020). In contrast, the hemodynamic responses (blood pressure, total peripheral resistance, cardiac output, and renal artery blood flow) to AngII were similar after potassium and placebo. Conclusions Increased potassium intake potentiates AngII-stimulated aldosterone secretion without affecting systemic cardiovascular hemodynamics in healthy normotensive men. Registration EudraCT Number: 2013-004460-66; URL: https://www.ClinicalTrials.gov; Unique identifier: NCT02380157.

Background Exercise stress tests are conventionally performed to assess risk of coronary artery disease. Using the FHS (Framingham Heart Study) Offspring cohort, we related blood pressure (BP) and heart rate responses during and after submaximal exercise to the incidence of heart failure (HF). Methods and Results We evaluated Framingham Offspring Study participants (n=2066; mean age, 58 years; 53% women) who completed 2 stages of an exercise test (Bruce protocol) at their seventh examination (1998-2002). We measured pulse pressure, systolic BP, diastolic BP, and heart rate responses during stage 2 exercise (2.5 mph at 12% grade). We calculated the changes in systolic BP, diastolic BP, and heart rate from stage 2 to recovery 3 minutes after exercise. We used Cox proportional hazards regression to relate each standardized exercise variable (during stage 2, and at 3 minutes of recovery) individually to HF incidence, adjusting for standard risk factors. On follow-up (median, 16.8 years), 85 participants developed new-onset HF. Higher exercise diastolic BP was associated with higher HF with reduced ejection fraction (ejection fraction <50%) risk (hazard ratio [HR] per SD increment, 1.26; 95% CI, 1.01-1.59). Lower stage 2 pulse pressure and rapid postexercise recovery of heart rate and systolic BP were associated with higher HF with reduced ejection fraction risk (HR per SD increment, 0.73 [95% CI, 0.57-0.94]; 0.52 [95% CI, 0.35-0.76]; and 0.63 [95% CI, 0.47-0.84], respectively). BP and heart rate responses to submaximal exercise were not associated with risk of HF with preserved ejection fraction (ejection fraction ≥50%). Conclusions Accentuated diastolic BP during exercise with slower systolic BP and heart rate recovery after exercise are markers of HF with reduced ejection fraction risk.

[Figure: see text].

Background: Regular exercise is an effective intervention to yield health-related benefits, though an optimal dosage and its ability to improve hemodynamics at rest and during exercise are yet to be established. Therefore, this study aimed to assess the effects of a combined (aerobic and resistance) exercise training program on hemodynamic variables at rest and during exercise in young obese prehypertensive men., Methods: Twenty obese prehypertensive men (age: 20±1.2 years) were randomly assigned to either the combined exercise training group (CBT, N.=10), or the control group (CON, N.=10). The CBT underwent a supervised combined exercise training program incorporating four 60-min sessions per week over 12 weeks, whereas the CON remained in habitual activities. We assessed BP, peak oxygen consumption (V̇O2peak), body composition, muscular strength, and hemodynamic responses to incremental exercise at baseline and post intervention., Results: The study revealed significant improvements in resting systolic blood pressure (SBP) of 4.3% (P<0.05), and rate-pressure product (RPP) of 11.3% (P<0.05) following 12 weeks of training. Significant reductions in SBP and RPP during exercise were also present at every exercise intensity. Moreover, the CBT training improved V̇O2peak by 18.2% (P<0.01), upper body muscle strength by 15.1% (P<0.01), and reduced body fat (P<0.01)., Conclusions: The CBT is effective in reducing SBP and myocardial oxygen demand at rest and during exercise. It can also improve cardiorespiratory fitness, muscular strength, and reduce body fat; especially in terms of abdominal obesity. Thus, we suggest the use of the CBT program for the prevention of future hypertension in young obese prehypertensive men.

Thoracic aortic aneurysm is a disease associated with high morbidity and mortality. Clinically useful strategies for medical management of thoracic aortic aneurysm are critically needed. To address this need, we sought to determine the role of aortic stiffness and pulsatile arterial load on future aneurysm expansion. One hundred five consecutive, unoperated subjects with thoracic aortic aneurysm were recruited and prospectively followed. By combining arterial tonometry with echocardiography, we estimated measures of aortic stiffness, central blood pressure, steady, and pulsatile arterial load at baseline. Aneurysm size was measured at baseline and follow-up with imaging; growth was calculated in mm/y. Stepwise multivariable linear regression assessed associations of arterial stiffness and load measures with aneurysm growth after adjusting for potential confounders. Mean±SD age, baseline aneurysm size, and follow-up time were 62.6±11.4 years, 46.24±3.84 mm, and 2.92±1.01 years, respectively. Aneurysm growth rate was 0.43±0.37 mm/y. After correcting for multiple comparisons, higher central systolic (β±SE: 0.026±0.009, P =0.007), and pulse pressures (β±SE: 0.032±0.009, P =0.0002), carotid-femoral pulse wave velocity (β±SE: 0.032±0.011, P =0.005), amplitudes of the forward (β±SE: 0.044±0.012, P =0.0003) and reflected (β±SE: 0.060±0.020, P =0.003) pressure waves, and lower total arterial compliance (β±SE: -0.086±0.032, P =0.009) were independently associated with future aneurysm growth. Measures of aortic stiffness and pulsatile hemodynamics are independently associated with future thoracic aortic aneurysm growth and provide novel insights into disease activity. Our findings highlight the role of central hemodynamic assessment to tailor novel risk assessment and therapeutic strategies to patients with thoracic aortic aneurysm.

To evaluate the left ventricular end diastolic pressure (LVEDP) in patients with diastolic heart failure by echocardiography and explore the clinical value of echocardiography.From July 2017 to January 2018, 120 patients were prospectively selected from the affiliated hospital of Jiangsu university diagnosed as diastolic heart failure (York Heart Association class ≥II, LVEF ≥50%). The patients were divided into group with LVEDP ≤15 mm hg (1 mm hg = 0.133 kpa) (43 cases) and the group with LVEDP >15 mm hg (77 cases) according to the real-time measurement of LVEDP. Receiver operator characteristic curves of each parameter of echocardiography in diagnosis of LVEDP were compared between the 2 groups.Common ultrasonic parameters such as left ventricular inflow tract blood flow propagation velocity, mitral valve diastole e peak velocity/mitral valve diastole a peak velocity, e peak deceleration time, a peak duration, and early diastole interventricular septum bicuspid annulus velocity e' (e'sep) were used to evaluate LVEDP elevation with low accuracy (AUC is only between 0.5 and 0.7). Other ultrasonic parameters such as left atrial volume index (LAVI), tricuspid regurgitation maximum flow rate (TRmax), early diastole left ventricular sidewall bicuspid annulus velocity e' (e'lat), average e', E/e'sep, E/e'lat, average E/e' were used to evaluate LVEDP elevation with a certain improvement in accuracy (AUC between 0.7 and 0.9). Propagation velocity, mitral valve diastole e peak velocity/mitral valve diastole a peak velocity, e peak deceleration time, a peak duration, e'sep, average e', E/e'sep have very low correlation with LVEDP (r = -0.283 to 0.281); LAVI, TRmax, e'lat, E/e'lat, average E/e' and LVEDP are not highly correlated (r = 0.330-0.478). Through real-time left ventricular manometry, multiple regression analysis showed that TRmax, average e', e'lat, LAVI were independently correlated with the actual measured LVEDP.Echocardiography can recognize the increase of LVEDP in patients with heart failure preserved by LVEF, and estimate the value of LVEDP roughly, which can reflect LVEDP to a certain extent, with high feasibility and accuracy.

A combination of yoga and blood flow restriction, each of which elicits marked pressor responses, may further increase blood pressure and myocardial oxygen demand. To determine the impact of a combination of yoga and blood flow restriction on hemodynamic responses, twenty young healthy participants performed 20 yoga poses with/without blood flow restriction bands placed on both legs. At baseline, there were no significant differences in any of the variables between the blood flow restriction and non-blood flow restriction conditions. Blood pressure and heart rate increased in response to the various yoga poses (p<0.01) but were not different between the blood flow restriction and non-blood flow restriction conditions. Rate-pressure products, an index of myocardial oxygen demand, increased significantly during yoga exercises with no significant differences between the two conditions. Rating of perceived exertion was not different between the conditions. Blood lactate concentration was significantly greater after performing yoga with blood flow restriction bands (p=0.007). Cardio-ankle vascular index, an index of arterial stiffness, decreased similarly after yoga exercise in both conditions while flow-mediated dilation remained unchanged. In conclusion, the use of lower body blood flow restriction bands in combination with yoga did not result in additive or synergistic hemodynamic and pressor responses., Competing Interests: A conflict of interest was declared by Sten Stray-Gundersen, whose family members are employed by BStrongTm, Park City, Utah. For the remaining authors, none were declared., (Thieme. All rights reserved.)

Recently, we reported a mutation in γ-adducin (ADD3) was associated with an impaired myogenic response of the afferent arteriole and hypertension-induced chronic kidney disease (CKD) in fawn hooded hypertensive (FHH) rats. However, the mechanisms by which altered renal blood flow (RBF) autoregulation promotes hypertension-induced renal injury remain to be determined. The present study compared the time course of changes in renal hemodynamics and the progression of CKD during the development of DOCA-salt hypertension in FHH 1 BN congenic rats [wild-type (WT)] with an intact myogenic response versus FHH 1 BN Add3 KO ( Add3 KO) rats, which have impaired myogenic response. RBF was well autoregulated in WT rats but not in Add3 KO rats when blood pressure increased from 100 to 150 mmHg. After 1 wk of hypertension, glomerular filtration rate increased by 38% and glomerular nephrin expression decreased by 20% in Add3 KO rats when blood pressure increased from 100 to 150 mmHg. After 1 wk of hypertension, glomerular filtration rate increased by 38% and glomerular nephrin expression decreased by 20% in Add3 KO rats. Neither were altered in WT rats. Proteinuria doubled in WT rats versus a sixfold increase in Add3 KO rats. The degree of renal injury was greater in Add3 KO than WT rats after 3 wk of hypertension. RBF, glomerular filtration rate, and glomerular capillary pressure were lower by 20%, 28%, and 19% in Add3 KO rats than in WT rats, which was associated with glomerular matrix expansion and loss of capillary filtration area. The results indicated that impaired RBF autoregulation and eutrophic remodeling of preglomerular arterioles increase the transmission of pressure to glomeruli, which induces podocyte loss and accelerates the progression of CKD in hypertensive Add3 KO rats.

Background: Measurement of blood pressure is part of standard monitoring procedures in anesthesia, in addition to the other vital parameters of heart frequency and peripheral oxygen saturation. In recent years the relevance of the duration and extent of perioperative episodes of hypotension for the occurrence of postoperative complications or even increased mortality have become the focus of scientific investigations., Objective: The aim of this review is to briefly recapitulate the physiological aspects of blood pressure and to describe the pathophysiology and risk factors of perioperative hypotension. It describes which potential organ damage can be caused by hypotension and discusses which perioperative blood pressure values are acceptable without harming the patient., Methods: Review and analysis of the currently available literature., Results: Perioperative hypotension is defined by either absolute systolic arterial pressure (SAP) or mean arterial pressure (MAP) thresholds and by relative blood pressure declines from an individual preoperative baseline value. For the definition of absolute and relative thresholds it needs to be considered that the ultimate target is an adequate perfusion pressure (and not the MAP) and that the preinduction blood pressure is a poor reflection of the patients' normal blood pressure profile. Risk factors for an intraoperative drop in blood pressure are advanced age, higher American Society of Anesthesiologists (ASA) status, low blood pressure prior to induction of anesthesia, the premedication, e.g. angiotensin-converting enzyme (ACE) inhibitors, the anesthesia technique (combination of general and epidural anesthesia) and emergency surgery. The lowest tolerable intraoperative blood pressure should be defined according to the individual patient's preoperative blood pressure and risk profile. Individual thresholds should be determined for the severity and duration of intraoperative hypotension. Empirically, MAP values <65 mm Hg and relative pressure declines of >20-30% are often recommended as thresholds. Below critical blood pressure values the risk of postoperative organ damage (myocardium, kidneys and central nervous system) and mortality increases with longer duration of hypotension. Older people and high-risk patients (e.g. patients in vascular surgery) have a poorer and shorter tolerance of low blood pressure. Postoperative organ complications can be minimized by maintenance of an adequate intraoperative blood pressure CONCLUSION: Anesthesiologists should avoid extensive and prolonged hypotension by timely interventions in order to improve the postoperative outcome of patients.

Blood pressure (BP) responses to exercise yield prognostic information beyond resting BP. While habitual higher dietary protein intake is associated with reduced resting BP, few studies have assessed the impact of high-protein meals on acute BP and vasoactive biomarker responses to exercise. To test the hypothesis that consuming a higher-protein, lower fat meal (HP; 30 g protein, 17 g fat, 52 g carbohydrate) would attenuate the BP response to exercise and result in a more robust post-exercise hypotensive response compared to a lower-protein, higher-fat meal (LP; 13 g protein, 25 g fat, 54 g carbohydrate), we recruited 31 pre-hypertensive subjects to complete this randomized, double-blind, cross-over acute feeding study. One hundred sixty-five minutes after consuming the test HP or LP meal, subjects exercised on a cycle ergometer at 70% VO 2 max for 30 minutes. Blood pressure was measured prior to the meal and periodically before, during, and after exercise for a 315-minute period. Blood samples were periodically collected to quantify plasma arginine, arginine metabolites (asymmetric dimethylarginine, symmetric dimethylarginine; ADMA, SDMA), endothelin-1, nitrates, and nitrites in a subset of subjects (n = 15) as shown in Supplemental Table S1. Consuming the HP meal did not influence the BP responses to exercise, including the post-exercise return to baseline BP or systolic BP area under the curve. While the HP meal resulted in greater postprandial plasma arginine concentrations, ADMA, SDMA, endothelin-1, nitrates, and nitrites were unaltered. These results suggest that consuming a higher-protein, lower-fat meal does not influence BP or vasoactive biomarker responses to exercise compared to a lower-protein, higher-fat meal., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aim: Blood flow restriction (BFR) exercise is a common alternative to traditional high-load resistance exercise used to increase muscle size and strength. Some populations utilizing BFR at a low load may wish to limit their cardiovascular response to exercise. Different contraction patterns may attenuate the cardiovascular response, but this has not been compared using BFR., Purpose: To compare the cardiovascular response to unilateral (UNI), bilateral (BIL), and alternating (ALT) BFR exercise contraction patterns., Methods: Twenty healthy participants performed four sets (30 s rest) of knee extensions to failure, using 30% one-repetition maximum, 40% arterial occlusion pressure, and each of the three contraction patterns (on different days, at the same time of day, separated by 2-10 days, randomized). Cardiovascular responses, presented as pre- to post-exercise mean changes (SD), were measured using pulse wave analysis and analyzed with Bayesian RMANOVA., Results: ALT caused greater changes in: aortic systolic [ΔmmHg: ALT = 21(8); UNI = 13(11); BIL = 15(8); BF 10  = 29.599], diastolic [ΔmmHg: ALT = 13(8); UNI = 7(11); BIL = 8(8); BF 10  = 5.175], and mean arterial [ΔmmHg: ALT = 19(8); UNI = 11(11); BIL = 13(7); BF 10  = 48.637] blood pressures. Aortic [ΔmmHg bpm: ALT = 4945(2340); UNI = 3294(1408); BIL = 3428 (1461); BF 10  = 113.659] and brachial [ΔmmHg bpm: ALT = 6134(2761); UNI = 4300(1709); BIL = 4487(1701); BF 10  = 31.845] rate pressure products, as well as heart rate [Δbpm: ALT = 26(14); UNI = 19(8); BIL = 19(11); BF 10  = 5.829] were greatest with ALT. Augmentation index [Δ%: UNI = -6(13); BIL = - 7(11); ALT = - 5(16); BF 10  = 0.155] and wave reflection magnitude [Δ%: UNI = - 5(9); BIL = - 4(7); ALT = - 4(7); BF 10  = 0.150] were not different., Conclusion: Those at risk of a cardiovascular event may choose unilateral or bilateral BFR exercise over alternating until further work determines the degree to which it can be tolerated.

Background:  Physical training (ET) is important to restore the reflex sensitivity involved in controlling blood pressure in various diseases. Recent investigations have demonstrated an interaction between cardiopulmonary baroreceptors and arterial baroreflex during dynamic exercise. Objective: Considering that acute and chronic hemodynamic responses to swimming (SW) are different from the race (RUN), the objective of this study was to evaluate the effect of SW and RUN on baroreflex response before and after acute volume expansion in spontaneously hypertensive rats (SHR). Methods: SHR were divided into three groups: RUN, SW and sedentary (SED) groups. After training, the mean arterial pressure (MAP) and heart rate (HR) were recorded. Baroreflex response was assessed before and after acute volume expansion. Results: Both ET conditions reduced basal levels of HR and MAP. The first volume of injected isotonic saline solution (1.25% of body weight) produced a greater decrease in HR for the SW group (-105.8 ± 8.7 bpm) compared to RUN groups (-68 ± 5.2 bpm) and SED (-49.8 ± 7.2 bpm). Both training modalities increase the baroreflex response in relation to the SED group, but after the total volume expansion, the SW group presented attenuated response (0.7 ± 0.1 μPIms/mmHg) compared to RUN (1.5 ± 0.17 PIms/mmHg) and was not different from SED group (0.8 ± 0.2 mPIms/mmHg). Conclusion:  The results show that the swim-trained group has a different baroreflex response to that observed by the run-trained group after the activation of the load receptors by saline expansion.

Telomeres are short segments in chromosome ends, the length of which is reduced during cell lifecycles. We examined the association of mean leukocyte telomere length (LTL) and short telomere proportion (STP) with hemodynamic variables in normotensive and never-treated hypertensive volunteers (n=566, 19-72 years). STP and mean LTL were determined using Southern blotting, and supine hemodynamics recorded using continuous tonometric pulse wave analysis and whole-body impedance cardiography. The analyses were adjusted for age, body mass index (BMI), alcohol use, smoking, plasma chemistry, and estimated glomerular filtration rate (eGFR). In univariate analyses, mean LTL and STP both correlated with age, BMI, eGFR, aortic blood pressure, augmentation index, and pulse wave velocity (p<0.05 for all). Mean LTL also correlated with systemic vascular resistance (p<0.05). In linear regression analyses of all hemodynamic variables, mean LTL was only an independent explanatory factor for augmentation index (Beta -0.006, p=0.032), while STP was not an explanatory factor for any of the hemodynamic variables, in contrast to age, BMI and several cardiovascular risk factors. To conclude, augmentation index was predominantly related with chronological aging, but also with mean LTL, suggesting that this variable of central wave reflection is a modest marker of vascular biological aging.

We aimed to examine aneurysm hemodynamics with intra-saccular pressure measurement, and compare the effects of coiling, stenting and stent-assisted coiling in proximal segments of intracranial circulation. A cohort of 45 patients underwent elective endovascular coil embolization (with or without stent) for intracranial aneurysm at our department. Arterial pressure transducer was used for all measurements. It was attached to proximal end of the microcatheter. Measurements were taken in the parent artery before and after embolization, at the aneurysm dome before embolization, after stent implantation, and after embolization. Stent-assisted coiling was performed with 4 different stents: LVIS and LVIS Jr (Microvention, Tustin, CA, USA), Leo (Balt, Montmorency, France), Barrel VRD (Medtronic/ Covidien, Irvine, CA, USA). Presence of the stent showed significant reverse correlation with intra-aneurysmal pressure-both systolic and diastolic-after its implantation (r = -0.70 and r = -0.75, respectively), which was further supported by correlations with stent cell size-r = 0.72 and r = 0.71, respectively (P<0.05). Stent implantation resulted in significant decrease in diastolic intra-aneurysmal pressure (p = 0.046). Systolic or mean intra-aneurysmal pressure did not differ significantly. Embolization did not significantly change the intra-aneurysmal pressure in matched pairs, regardless of the use of stent (p>0.05). In conclusion, low-profile braided stents show a potential to divert blood flow, there was significant decrease in diastolic pressure after stent placement. Flow-diverting properties were related to stent porosity. Coiling does not significantly change the intra-aneurysmal pressure, regardless of packing density., Competing Interests: The authors have declared that no competing interests exist.

This article is for clinicians considering impedance cardiography (ICG) for secondary prevention. ICG is an inexpensive noninvasive technology that can be used to assess hemodynamic function of the central cardiovascular system. Diverse abnormalities of ventricular function, systolic and diastolic, can be detected by ICG. Additional data pertaining to decompensation can be obtained by taking ICG readings with the patient performing postural change, from upright to supine, to quantify the compensatory response. Vascular load consists of resistive and pulsatile loads. Systemic vascular resistance can provide a measure of resistive load. Pulsatile load has two components: arterial stiffness and wave reflection. ICG can be used to calculate arterial compliance and detect aortic wave reflection. For stage 1 hypertension, a significant issue is whether a treating clinician should add pharmacotherapy to lifestyle modification. Adults who have multiple cardiovascular risk factors with stage 1 hypertension have early cardiovascular disease. ICG can be used to identify the functional abnormalities associated with the cardiovascular disease. For the management of hypertension, ICG can be used to calculate the underlying hemodynamic parameters of cardiac index and systemic vascular resistance associated with a patient's blood pressure. There can be wide ranges for cardiac index and systemic vascular resistance, with many patients having low cardiac index with high systemic vascular resistance or vice versa. These hemodynamic data can be used to customize pharmacotherapy. Drug titration can be guided by patient response to treatment using the initial hemodynamic data as a baseline for comparison to subsequent measurements from serial office visits.

Background and Purpose- There is debate over an optimal systolic blood pressure (SBP) in secondary stroke prevention of patients with symptomatic intracranial atherosclerotic stenosis (sICAS). We investigated whether translesional pressure gradient across sICAS would alter the relationship between SBP and risk of recurrent stroke in such patients. Methods- We recruited patients with sICAS (50%-99% stenosis) confirmed in computed tomography angiography. We simulated blood flow across sICAS with computed tomography angiography-based computational fluid dynamics models. Translesional pressure ratio (PR=Pressure post-stenotic /Pressure pre-stenotic ) was calculated in each case. Pressure ratio (PR) ≤ median was defined as low PR, indicating larger translesional pressure gradient across sICAS. All patients received optimal medical treatment. We investigated the interaction of translesional PR and mean SBP during follow-up (SBP FU ) in determining the risk of the primary outcome, recurrent ischemic stroke in the same territory within 1 year. Results- Among 157 patients with sICAS, the median PR was 0.93. Multivariate Cox regression revealed significant PR-SBP FU interaction on the primary outcome ( P =0.008): in patients with normal PR, risk of primary outcome significantly decreased with lower SBP FU (hazard ratio for 10 mm Hg decrement =0.46; P =0.018); however, in those with low PR, SBP FU ≤130 mm Hg was associated with significantly increased risk of primary outcome, compared with 130FU <150 mm Hg (hazard ratio=5.08; P =0.043). Conclusions- Low SBP level may be associated with increased risk of stroke recurrence in patients with sICAS with a large translesional pressure gradient. Translesional PR by computational fluid dynamics models may yield a promising indicator to guide more individualized blood pressure management in patients with sICAS, warranting future studies.

Endothelial dysfunction is thought to underpin atherosclerotic cardiovascular disease. The most widely used in vivo test of endothelial function is flow-mediated dilation (FMD). However, the results of FMD may be subject to some confounding factors that are not fully understood. We investigated potential biophysical confounding factors that could cause a disassociation between FMD and true endothelial cell shear stress response (the release of endothelium-dependent relaxing factors in response to wall shear stress). Arterial hemodynamics during FMD was simulated using a novel computational modeling approach. The model included an endothelial response function relating changes in wall shear stress to changes in local vascular stiffness in the arm arteries and accounted for vascular stiffening with increasing blood pressure. The hemodynamic effects of cuff inflation and deflation were modeled by prescribing intraluminal arterial pressure changes and peripheral vasodilation. Evolution of arterial diameter and flow velocity during FMD was assessed by comparison against in vivo data. Our model revealed that vasoconstriction occurring immediately after cuff deflation is independent of endothelial response function and entirely caused by the change in transmural pressure along conduit arteries. Moreover, for the same endothelial response function model, FMD values increased exponentially with increasing peak flow velocity, decreased linearly with increasing arterial stiffness at a rate of 0.95%/MPa, and increased linearly with increasing central blood pressure at a rate of 0.22%/mmHg. Dependence of FMD on confounding factors, such as arterial stiffness and blood pressure, suggests that the current FMD test may not reflect the true endothelial cell response. NEW & NOTEWORTHY First, a novel computational model simulating arterial hemodynamics during flow-mediated dilation (FMD) was proposed. Second, the model was used to explain why FMD may be influenced by endothelium-independent factors, showing that FMD results are 1 ) partly masked by the vasoconstriction due to the change in transmural pressure and 2 ) affected by physiological factors (i.e., arterial stiffness and arterial blood pressure) that are difficult to eliminate due to their multiple interactions.

Purpose: The aim of this study was to investigate the hemodynamic, oxidative stress (OS), and nitric oxide (NO) responses to a submaximal isometric exercise session (IES) involving large muscle mass., Methods: Fourteen hypertensive (HTG: age = 35.9 ± 8.1 yr, height = 1.73 ± 0.10 m, total body mass = 78.0 ± 15.8 kg) and 10 normotensive (NTG: age = 41.1 ± 9.4 yr, height = 1.71 ± 0.12 m, total body mass = 82.3 ± 22.4 kg) participants performed two experimental sessions in the leg press and bench press: (i) control session and (ii) 8 sets × 1 min contraction at 30% maximal voluntary isometric contraction with 2-min rest interval. Blood pressure (BP) was measured at rest and during 60 min postexercise. Blood samples were collected at rest, immediately after the session, and 60 min postexercise. NO was obtained through the Griess reaction method. OS parameters were analyzed using commercial kits. A repeated-measures ANOVA with Bonferroni post hoc test was used to analyze all dependent variables., Results: A significant decrease in systolic BP was observed only for HTG at 45 and 60 min postexercise (baseline vs 45 min: P = 0.03, Δ% = 4.44%; vs 60 min: P = 0.018, Δ% = 5.58%). NO increased immediately postexercise only for HTG (P = 0.008, Δ% = 16.44%). Regarding OS parameters, thiobarbituric acid reactive substances presented a significant reduction 60 min after the IES for NTG and HTG; catalase increased in both groups., Conclusions: The data showed that only 8 min of IES with a large muscle mass elicits an elevated pro-oxidant activity leading to a greater NO bioavailability, increases antioxidant reaction, and consequently reduces BP in hypertensive patients.

Background Two individuals can have a similar pulse pressure (PP) but different levels of systolic blood pressure (SBP), although the underlying mechanisms have not been described. We hypothesized that, for a given level of PP, differences in SBP relate to peripheral vascular resistance (PVR); and we tested this hypothesis in a large cohort of healthy young adults. Methods and Results Demographic, biochemical, and hemodynamic data from 3103 subjects were available for the current analyses. In both men and women, for a given level of PP, higher SBP was associated with significantly higher body weight, body mass index, heart rate, and PVR ( P <0.05 versus those with lower BP for all comparisons). Moreover, stratifying individuals by quartiles of PP and PVR revealed a stepwise increase in SBP from the lowest to highest quartile for each variable, with the highest SBP occurring in those in the highest quartile of both PP and PVR ( P <0.001 for overall trend for both sexes). PVR was also increased with increasing tertile of minimum forearm vascular resistance, in both men ( P =0.002) and women ( P =0.03). Conclusions Increased PVR, mediated in part through altered resistance vessel structure, strongly associates with the elevation of SBP for a given level of PP in young adults. An impaired ability to adapt PVR appropriately to a given level of PP may be an important mechanism underlying elevated SBP in young adults.

In the past decades, substantial effort has been devoted to the development of computational models of the cardiovascular system. Some of these models simulate blood pressure regulation in humans and include components of the circulatory, renal, and neurohormonal systems. Although such human models are intended to have clinical value in that they can be used to assess the effects and reveal mechanisms of hypertensive therapeutic treatments, rodent models would be more useful in assisting the interpretation of animal experiments. Also, despite well-known sexual dimorphism in blood pressure regulation, almost all published models are gender neutral. Given these observations, the goal of this project is to develop the first computational models of blood pressure regulation for male and female rats. The resulting sex-specific models represent the interplay among cardiovascular function, renal hemodynamics, and kidney function in the rat; they also include the actions of the renal sympathetic nerve activity and the renin-angiotensin-aldosterone system as well as physiological sex differences. We explore mechanisms responsible for blood pressure and renal autoregulation and notable sexual dimorphism. Model simulations suggest that fluid and sodium handling in the kidney of female rats, which differs significantly from males, may contribute to their observed lower salt sensitivity as compared with males. Additionally, model simulations highlight sodium handling in the kidney and renal sympathetic nerve activity sensitivity as key players in the increased resistance of females to angiotensin II-induced hypertension as compared with males.

Objective: To evaluate whether changing dopamine infusions every 12 hours and preparing these infusions 30 min before administration reduces blood pressure fluctuations in preterm and term neonates., Design: This was a retrospective study using data from live patients on the neonatal unit and prospective study exploring stability of infusions in a laboratory-based neonatal ward simulation., Setting: Single-centre study in a tertiary neonatal surgical unit in a university teaching hospital., Patients: Neonates who received more than one subsequent dopamine infusion and had invasive arterial blood pressure monitoring, during their admission in the neonatal unit, were included., Interventions: As part of the Quality Improvement project, the standard operating procedure (SOP) was changed, and dopamine infusions were prepared by nursing staff and left to rest for 30 min before administering to the neonate. Additionally, infusions were replaced every 12 hours., Main Outcome Measures: The percentage change in mean arterial pressure (MAP) and the percentage loss in the drug concentration during infusion during changeover., Results: Our findings indicate that up to 15% of the initial dopamine concentration is lost after 24 hours. This results in a sharp variation in the dopamine concentration during infusion changeover that correlates with observed rapid fluctuations in MAP. In changing the SOP, no significant difference in the concentration of dopamine and MAP were observed over 12 hours., Conclusions: Delaying administration of dopamine infusions by 30 min after preparation combined with changing infusions 12 hourly has reduced MAP fluctuations. Therefore, the risks associated with MAP fluctuations, including intraventricular haemorrhages, are reduced., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

The major clinical associations with the progression of diabetic kidney disease (DKD) are glycemic control and systemic hypertension. Recent studies have continued to emphasize vasoactive hormone pathways including aldosterone and endothelin which suggest a key role for vasoconstrictor pathways in promoting renal damage in diabetes. The role of glucose per se remains difficult to define in DKD but appears to involve key intermediates including reactive oxygen species (ROS) and dicarbonyls such as methylglyoxal which activate intracellular pathways to promote fibrosis and inflammation in the kidney. Recent studies have identified a novel molecular interaction between hemodynamic and metabolic pathways which could lead to new treatments for DKD. This should lead to a further improvement in the outlook of DKD building on positive results from RAAS blockade and more recently newer classes of glucose-lowering agents such as SGLT2 inhibitors and GLP1 receptor agonists.

Limited data exist evaluating the effect of blood pressure (BP) on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with mechanical thrombectomy (MT). We sought to evaluate the association of BP levels on clinical outcomes among patients with acute ischemic stroke with large vessel occlusion treated with MT. Studies were identified that reported the association of systolic BP (SBP) or diastolic BP levels before, during, or after MT on the outcomes of patients with acute ischemic stroke treated with MT. Unadjusted and adjusted analyses of studies reporting odds ratios (OR adj ) per 10 mm Hg BP increment were performed. Our analysis included 25 studies comprising 6474 patients. Higher pre-MT mean SBP ( P =0.008) and post-MT maximum SBP ( P =0.009) levels were observed in patients who died within 3 months. Patients with 3-month functional independence were noted to have lower pre-MT ( P <0.001) and post-MT maximum SBP levels ( P <0.001). In adjusted analyses, increasing post-MT maximum SBP and diastolic BP levels were associated with 3-month mortality (OR adj , 1.19 [95% CI,1.00-1.43]; I 2 =78%, P value for Cochran Q test: 0.001) and symptomatic intracranial hemorrhage (OR adj , 1.65 [95% CI, 1.11-2.44]; I 2 =0%, P value for Cochran Q test: 0.80), respectively. Increasing pre- and post-MT mean SBP levels were associated with lower odds of 3-month functional independence (OR adj , 0.86 [95% CI, 0.77-0.96]; I 2 =18%, P value for Cochran Q test: 0.30) and (OR adj , 0.80 [95% CI, 0.72-0.89]; I 2 =0%, P value for Cochran Q test: 0.51), respectively. In conclusion, elevated BP levels before and after MT are associated with adverse outcomes among patients with acute ischemic stroke with large vessel occlusion.

Impaired renal autoregulation permits more transmission of disturbance in systemic blood pressure, which initiates barotrauma in intrarenal microvasculatures such as glomerular and tubulointerstitial capillaries, contributing to the development of kidney damage and deterioration in renal function, especially under the conditions with high blood pressure. Although it has been postulated that autoregulatory efficiency is attenuated in the aging kidney, direct evidence remains lacking. In the present study, we measured the autoregulation of renal blood flow, myogenic response of afferent arteriole (Af-Art), tubuloglomerular feedback in vivo with micropuncture, as well as tubuloglomerular feedback in vitro in isolated perfused juxtaglomerular apparatus in young and aged C57BL/6 mice. We found that renal blood flow was not significantly changed in response to a defined elevation of renal arterial pressure in young mice but significantly increased in aged mice. Additionally, myogenic response of Af-Art measured by microperfusion with a stepwise increase in perfusion pressure was significantly blunted in the aging kidney, which is associated with the attenuation of intraluminal pressure-induced intracellular calcium increases, as well as the reduced expression of integrin α5 (Itga5) in Af-Art. Moreover, both tubuloglomerular feedback in vivo and in vitro were nearly inactive in the aging kidney, which is associated with the significantly reduced expression of adenosine A1 receptor (A1AR) and suppressed vasoconstrictor response to adenosine in Af-Art. In conclusion, this study demonstrates that aging impairs renal autoregulation with blunted myogenic response and inhibited tubuloglomerular feedback response. The underlying mechanisms involve the downregulations of integrin α5 and A1AR in the Af-Art.

Assessment of the cerebrovascular and cardiovascular response to standing has prognostic value for a range of outcomes in the older adult population. Studies generally attempt to control for standing speed differences by asking participants to stand in a specified time but little is known about the range of transition times observed. This study aimed to characterize how standing speed associates with cardiovascular and cerebrovascular measures following transition from supine to standing. Continuous cerebral oxygenation, heart rate, systolic and diastolic blood pressure were monitored for 3 minutes after transitioning from supine to standing. An algorithm was used to calculate the time taken to transition from existing Finometer data (from the height correction unit). Linear mixed-effects models were used to assess the influence of transition time on each of the signals while adjusting for covariates. Transition time ranged from 2 to 27 s with 17% of participants taking >10 s to stand. Faster transition was associated with a more extreme decrease 10 s after standing but improved recovery at 20 s for cerebral oxygenation and blood pressure. Standing faster was associated with an elevated heart rate on initiation of stand and a quicker recovery 10 to 20 s after standing. The speed of transitioning from supine to standing position is associated with cardiovascular and cerebrovascular response in the early period after standing (<40 s). Care should be taken in the interpretation of findings which may be confounded by standing speed and statistical adjustment for standing time should be applied where appropriate.

Cardiovascular adaptations to pregnancy involve physiological mechanisms that increase cardiac output, decrease total vascular resistance, and decrease both systolic and diastolic blood pressure (BP). These maternal hemodynamic changes modulate uteroplacental blood flow and fetal-placental Doppler indices. Our objective was to create maternal cardiac profiles of pregnant women using non-invasive measurements of central BP to identify changes in maternal-fetal hemodynamics as a surrogate to fetal status. This was a prospective cohort study of all singleton pregnancies in a perinatal referral center between January and April 2018. Central BP was measured non-invasively using the BP+ device. The BP+ device is a supra-systolic oscillometric central BP device, which measures BP waveforms peripherally and calculates central BP. We compared various BP+ values for peripheral BP with central BP and stratified by gestational age. We investigated the correlations between peripheral BP, central BP, estimated fetal weight (EFW), and the pulsatility indices (PI) of Doppler velocimetry and demonstrate that both central systolic and diastolic BP correlated to peripheral systolic and diastolic BP. Linear regression analysis confirmed that central BP predicts the middle cerebral artery (MCA) PI. The MCA PI correlated with EFW, specifically higher central systolic BP is associated with a lower MCA PI, implying a possible etiology of fetal brain shunting with poor placental perfusion. Future studies using predictors and markers of fetal outcomes from maternal cardiac parameters should consider maternal cardiovascular measurements to peripheral arterial BP.