Quantitative Evaluation of Right Ventricular Workload Based on the Stroke Work Index in Patients after Right Ventricular Outflow Tract Reconstruction.

The evaluation of right ventricular workload is sometimes complicated in patients after right ventricular outflow tract reconstruction (RVOTR) because both stenotic and regurgitation lesions are involved. In this study, we modified the right ventricular stroke work index (RVSWI) and evaluated the relationship between the modified RVSWI (mRVSWI) and patient prognosis after RVOTR.We enrolled 69 patients who underwent RVOTR (the RVOTR group), including those who needed early reoperation (early reoperation subgroup) and those who did not (follow-up subgroup), and 13 age-matched control participants (control group). Based on the catheterization results 1 year after RVOTR, we compared the mRVSWI between these groups. Additionally, we evaluated the influence of the mRVSWI on the reoperation avoidance rate and survival.The mRVSWI in the RVOTR group was significantly greater than that in the control group (17.7 ± 8.6 vs. 11.0 ± 2.7 g·m/m2, p = 0.008). The mRVSWI in the early reoperation subgroup was significantly greater than that in the follow-up subgroup (32.5 ± 11.1 vs. 15.8 ± 6.0 g·m/m2, p < 0.0001). In the follow-up subgroup, patients with an mRVSWI higher than the upper limit of normal (16.4 g·m/m2) had a greater rate of reoperation than did the other patients (p = 0.0013). One patient died suddenly, and her mRVSWI was consistently high throughout her life.We established the mRVSWI as an index that integrates the pressure and volume load on the right ventricle. Our results indicate the utility of the mRVSWI for predicting patient prognosis after RVOTR.

Computational Analysis of the Effects of Fiber Deformation on the Microstructure and Permeability of Blood Oxygenator Bundles.

Mechanical loads on the polymeric fibers of oxygenating bundles are commonly present due to bundle press-fitting during device assembly and blood pressure load. However, computational fluid dynamics (CFD) simulations for fiber bundle optimization neglect possible changes in microstructure due to such deformations. The aim of this study is to investigate the impact of fiber deformability on bundle microstructure and fluid dynamics mainly in terms of permeability. Fibers from commercial mats typically used for blood oxygenators were mechanically tested and based on these experimental data, a material model was developed to simulate the structural deformations the fibers undergo under press-fitting and blood pressure loads. Then, CFD simulations were performed on deformed bundle repetitive units to investigate permeability under varying loading conditions. The effects of different bundle geometric parameters on the variation of bundle permeability due to press-fitting were evaluated. Bundle press-fitting results in significant changes in microstructure that are reflected in a bundle permeability more than halved for a 15% press-fitting. This impact on permeability is present in all the simulated fiber bundles and becomes more pronounced as the pitch between fibers and thus bundle porosity decreases. Instead, the analyses on pressurized bundle show only small deformations caused by pressure load, with permeability changes below 1%. While blood pressure effects could be neglected, bundle press-fitting turns out to have a significant impact on bundle microstructure and permeability. Neglecting such microstructure variations during CFD simulations could also lead to incorrect assessment of the local fluid dynamics within the bundle.

The effects of obstructive sleep apnea on blood pressure variability and load in patients with hypertension.

BACKGROUND: Hypertension frequently coexists with obstructive sleep apnea (OSA), and their interplay substantially impacts the prognosis of affected individuals. Investigating the influence of OSA on blood pressure variability (BPV) and blood pressure load (BPL) in hypertensive patients has become a focal point of clinical research. METHODS: This cross-sectional study recruited hypertensive patients (n = 265) without discrimination and classified them into four groups based on their apnea-hypopnea index (AHI): control group (n = 40), AHI < 5; mild group (n = 74), 5 ≤ AHI ≤ 15; moderate group (n = 68), 15 < AHI ≤ 30; severe group (n = 83), AHI > 30. All participants underwent comprehensive assessments, including polysomnography (PSG) monitoring, 24-h ambulatory blood pressure (ABP) monitoring, cardiac Doppler ultrasound, and additional examinations when indicated. RESULTS: BPV and BPL exhibited significant elevations in the moderate and severe OSA groups compared to the control and mild OSA groups (P < 0.05). Moreover, interventricular septum thickness and left ventricular end-diastolic volume (LVEDV) demonstrated higher values in the moderate and severe OSA groups (P < 0.05). Multiple stepwise regression analysis identified noteworthy risk factors for elevated BPV in hypertensive patients with OSA, including AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea. CONCLUSION: Hypertensive patients with moderate to severe OSA exhibited substantially increased BPV and BPL. Moreover, BPV was correlated with AHI, maximum apnea time, total times of oxygen reduction, and mean time of apnea in hypertensive patients with OSA.

Cumulative blood pressure load and hypertensive nephropathy in Han Chinese hypertensive patients.

The study aims to assess the relationship between cumulative blood pressure load (cBPL) and the risk of renal function decline in hypertensive patients and determine the blood pressure (BP) threshold required to prevent hypertensive nephropathy. A single-center prospective cohort study was conducted on hypertensive patients. The cBPL was defined as the proportion of area beyond variable BP cutoffs under ambulatory BP monitoring. Renal events were defined as > 25% (minor) or > 50% (major) decline of baseline estimated glomerular filtration rate (eGFR). Cox regression analysis was conducted between cBPL, other ambulatory BP parameters, and renal events. The results revealed a total of 436 Han Chinese hypertensive patients were eligible for enrollment. During an average follow-up period of 5.1 ± 3.3 years, a decline of > 25% and > 50% in eGFR was observed in 77 and eight participants, respectively. Cox regression analysis revealed that cSBPL140 (hazard ratio [HR], 1.102; 95% confidence interval [CI], 1.017-1.193; p = .017), cSBPL130 (HR, 1.076; 95% CI, 1.019-1.137; p = .008), and cSBPL120 (HR, 1.054; 95% CI, 1.010-1.099; p = .015) were independently associated with minor renal events. Similarly, cSBPL140 (HR, 1.228; 95% CI, 1.037-1.455; p = .017), cSBPL130 (HR, 1.189; 95% CI, 1.045-1.354; p = .009), and cSBPL120 (HR, 1.155; 95% CI, 1.039-1.285; p = .008) were independently associated with major renal events. In conclusion, cBPL is associated with renal function decline in hypertensive patients. Minimizing cBPL120 may decrease the risk of hypertensive nephropathy.

Echocardiographic multiparameter assessment for patients with heart failure with preserved ejection fraction and atrial fibrillation.

We aimed to assess the echocardiographic parameters of cardiac structure and function in patients with heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF). Thirty-seven HFpEF patients with AF were selected, while 38 patients with simple HFpEF in the same period were selected as controls. Three-dimensional speckle-tracking echocardiography was performed on both groups and the parameters were compared. The early diastolic longitudinal peak strain rates [early diastolic longitudinal strain rate (LSRE), early diastolic circumferential strain rate (CSRE), early diastolic radial strain rate (RSRE) and early diastolic rotational strain rate (RotRE)], late diastolic longitudinal peak strain rates (LSRA, CSRA, RSRA and RotRA) and untwisting parameters [untwisting rate during isovolumic relaxation time (UTRIVR) and early peak untwisting rate (UTRE)] were all negatively correlated with the ratio of early diastolic transmitral velocity to early diastolic mitral annular velocity ( E/E') (p < 0.01). The cardiac event-free survival rate of the simple HFpEF group (92.11%) was significantly higher than that of the HFpEF + AF group (81.08%) (p < 0.0001). UTRIVR had a more significant correlation with E/E' ratio than the other indicators and could serve as a sensitive indicator for evaluating the diastolic function of patients with HFpEF + AF.

The Role of Blood Pressure Load in Ambulatory Blood Pressure Monitoring in Adults: A Literature Review of Current Evidence.

BACKGROUND: The blood pressure load (BPL) is commonly defined as the percentage of readings in a 24-h ambulatory blood pressure monitoring (ABPM) study above a certain threshold, usually the upper normal limit. While it has been studied since the 1990s, the benefits of using this index have not been clearly demonstrated in adults. We present the first review on the associations of BPL with target organ damage (TOD) and clinical outcomes in adults, the major determinants for its role and utility in blood pressure measurement. We emphasize studies which evaluated whether BPL has added benefit to the average blood pressure indices on ABPM in predicting adverse outcomes. METHODS: PubMed search for all English language papers mentioning ABPM and BPL. RESULTS: While multiple studies assessed this question, the cumulative sample size is small. Whereas the associations of BPL with various TODs are evident, the available literature fails to demonstrate a clear and consistent added value for the BPL over the average blood pressure indices. CONCLUSIONS: There is a need for prospective studies evaluating the role of BPL in blood pressure measurement. The current literature does not provide sound support for the use of BPL in clinical decisions.

New estimation method of limit pressures for thick curved pipes under internal pressure applicable to various bend angles.

In this study, a new estimation method of limit pressures (loads) is suggested for reliability design of curved pipes under high internal pressure and temperature. The curved pipes are used in boiler pipes in a supercritical thermal power plants. To find any design parameters and their dimensions in reliability design of curved pipes, various boilers in supercritical thermal power plants in operation were investigated. In order to analyse the effect of the design parameters on the limit pressure, the design of experiment (DOE) was applied to design a curved pipes with various combinations of design parameters, and then the FE limit load analyses were performed to obtain limit pressures. The thickness of the curved pipe has the greatest effect on the limit pressure among the design parameters. Although the bend angle is design parameter, the proposed estimation methods for easily calculating the limit load do not include the bend angle and then there have been difficulties in reliability design of curved pipes with any band angle. Therefore, to solve such difficulties, two estimation methods of limit pressure (load) including bend angle were suggested and the validity of the proposed estimation methods of limit load (plastic pressure) under internal pressure was objectively verified through statistical error analysis with the 60 FE analysis results which are different from the data used when the method was derived. The proposed estimation method applicable to various bend angles shows the best results in the evaluation of mean error, maximum error, and standard deviation of error, which are evaluation criteria. The proposed estimation method shows a very good result compared to existing methods, having the mean error of 0.89%, a maximum error of 2.50%, and a standard deviation of 0.70% for all data regardless of the bend angle.

Home Blood Pressure Monitoring And Nocturia In Adults.

Although widely viewed as a urological condition, nocturia has been increasingly recognized to accompany various non-urological conditions such as hypertension and blood pressure (BP) elevation on office determination. Home BP monitoring (HBPM) has been shown superior to office-based readings and provides an opportunity to assess potential relationships between nocturia and novel indices derived from multiple BP recordings including BP load, BP variability, and arterial stiffness, which have prognostic significance. We retrospectively studied 103 home BP logs and nocturia frequencies provided by 61 stable cardiology patients ≥ 21 years without medication change. Nocturnal voids ranged from 0 to 5 voids per night, median: 1.5. Nocturia frequency was significantly correlated with home and office systolic BPs and with BP load, but not with diastolic BPs, BP variability or arterial stiffness. On Poisson regression analysis, the estimated prevalence ratio (PR) for home and office systolic BPs were 1.025 (CI: 1.01, 1.04; p < .001) and 1.01 (CI:1.00, 1.02; p = .019), indicating 2.5% and 1% increases in the risk of nocturia per mmHg increases in BP respectively. In conclusion, higher mean home and office systolic BPs are associated with self-reported nocturia frequency with stronger associations seen for home BP measurement. Nocturia frequency appears unrelated to mean home and office diastolic BPs. Nocturia may be related to BP load, (percentage of elevated BP values), but not to BP variability or arterial stiffness. Future prospective studies using HBPM are needed to confirm these findings and to contribute to the understanding of the elevated BP-nocturia link.

Inspiratory muscle training can improve the breathing, balance and walking of persons with Parkinson′s disease / 中华物理医学与康复杂志

Objective:To observe any effect of threshold pressure loaded inspiratory muscle training on the balance of persons with Parkinson′s disease (PD).Methods:Forty-eight persons with PD were randomly divided into an observation group and a control group, each of 24. Both groups were given conventional neurological drug treatment and conventional rehabilitation training. The observation group additionally completed inspiratory muscle training using a threshold pressure load trainer, 5 days per week for 8 weeks. Before and after the treatment, both groups′ inspiratory muscle functioning was quantified using ultrasound to assess diaphragm mobility and thickness, and maximum inspiratory pressure (MIP). Balance was quantified using Trunk Injury Scale (TIS) scoring, the Berg Balance Scale (BBS), limits of stability (LOS), and the timed up and go test (TUGT). Walking was evaluated using the 10-metre walk test (10MWT) and the Dynamic Gait Index (DGI).Results:After the treatment all of the indicators had improved significantly in both groups, on average, but those of the observation group were then significantly better. Correlation analysis showed that the difference in MIP of the observation group before and after treatment was significantly negatively correlated with the TUGT and 10MWT times.Conclusion:Threshold pressure loaded inspiratory muscle training combined with conventional rehabilitation therapy significantly improves the inspiratory muscle strength, balance and walking of persons with PD.

Arterial stiffness in aortic stenosis - complex clinical and prognostic implications.

Arterial stiffness and degenerative aortic stenosis (AoS) are frequently associated leading to a combined valvular and vascular load imposed on the left ventricle (LV). Vascular load consists of a pulsatile load represented by arterial stiffness and a steady load corresponding to vascular resistance. Increased vascular load in AoS has been associated with LV dysfunction and poor prognosis in pre-intervention state, as well as after aortic valve replacement (AVR), suggesting that the evaluation of arterial load in AoS may have clinical benefits. Nevertheless, studies that investigated arterial stiffness in AoS either before or after AVR used various methods of measurement and their results are conflicting. The aim of the present review was to summarize the main pathophysiological mechanisms which may explain the complex valvulo-arterial interplay in AoS and their consequences on LV structure and function on the patients' outcome. Future larger studies are needed to clarify the complex hemodynamic modifications produced by increased vascular load in AoS and its changes after AVR. Prospective evaluation is needed to confirm the prognostic value of arterial stiffness in patients with AoS. Simple, non-invasive, reliable methods which must be validated in AoS still remain to be established before implementing arterial stiffness measurement in patients with AoS in clinical practice.

The SGLT2i Dapagliflozin Reduces RV Mass Independent of Changes in RV Pressure Induced by Pulmonary Artery Banding.

BACKGROUND: Sodium glucose linked transporter 2 (SGLT2) inhibition not only reduces morbidity and mortality in patients with diagnosed heart failure but also prevents the development of heart failure hospitalization in those at risk. While studies to date have focused on the role of SGLT2 inhibition in left ventricular failure, whether this drug class is efficacious in the treatment and prevention of right heart failure has not been explored. HYPOTHESIS: We hypothesized that SGLT2 inhibition would reduce the structural, functional, and molecular responses to pressure overload of the right ventricle. METHODS: Thirteen-week-old Fischer F344 rats underwent pulmonary artery banding (PAB) or sham surgery prior to being randomized to receive either the SGLT2 inhibitor: dapagliflozin (0.5 mg/kg/day) or vehicle by oral gavage. After 6 weeks of treatment, animals underwent transthoracic echocardiography and invasive hemodynamic studies. Animals were then terminated, and their hearts harvested for structural and molecular analyses. RESULTS: PAB induced features consistent with a compensatory response to increased right ventricular (RV) afterload with elevated mass, end systolic pressure, collagen content, and alteration in calcium handling protein expression (all p < 0.05 when compared to sham + vehicle). Dapagliflozin reduced RV mass, including both wet and dry weight as well as normalizing the protein expression of SERCA 2A, phospho-AMPK and LC3I/II ratio expression (all p < 0.05). SIGNIFICANCE: Dapagliflozin reduces the structural, functional, and molecular manifestations of right ventricular pressure overload. Whether amelioration of these early changes in the RV may ultimately lead to a reduction in RV failure remains to be determined.

The Correlation Between ABPM Parameters and Left Ventricular Hypertrophy in Pediatric Essential Hypertension.

Objective: To explore the association of dipping pattern and blood pressure load with left ventricular hypertrophy (LVH) in pediatric essential hypertension. Materials and Methods: Through an echocardiography monitor and an ambulatory blood pressure monitor of 425 children and adolescents diagnosed with essential hypertension with no treatment received, we identified 140 cases of LVH. Grouping patients according to LVH (LVH, N = 140; n-LVH, N = 285), we further evaluated their ambulatory blood pressure monitoring (ABPM) parameters by comparing dipping patterns between groups. A multivariable logistic regression analysis was used to determine the effect of blood pressure load on LVH. Results: No significant difference was found in systolic or diastolic blood pressure dipping patterns between groups (P = 0.161, P = 0.139). However, compared to the n-LVH group, the LVH group presented significant elevated nighttime systolic blood pressure (SBP) (P < 0.05), while nighttime DBP remained stable (P = 0.391), resulting in higher daytime and nighttime SBP loads, higher nighttime DBP load, and higher 24-h SBP load (P < 0.05). Notably, our multivariable logistic regression has shown that this trend of 24-h SBP load acts independently as a critical risk factor for LVH. Conclusion: Collectively, we observed a correlation between BP load and LVH in pediatric hypertension. Our data demonstrated that SBP load has a more significant weight in LVH progression, and 24-h SBP load, in particular, acts as a critical early prognostic parameter for LVH in pediatric hypertension.

Neuregulin-1 enhances cell-cycle activity, delays cardiac fibrosis, and improves cardiac performance in rat pups with right ventricular pressure load.

OBJECTIVES: Right ventricular (RV) failure is a leading cause of death in patients with congenital heart disease. RV failure is kept at bay during childhood. Limited proliferation of cardiomyocytes is present in the postnatal heart. We propose that cardiomyocyte proliferation improves RV adaptation to pressure load (PL). We studied adaptation in response to increased RV PL and the role of increased cardiomyocyte cell cycle activity (CCA) in rat pups growing into adulthood. METHODS: We induced RV PL at day of weaning in rats (3 weeks; 30-40 g) by pulmonary artery banding and followed rats into adulthood (300 g). We performed histological analyses and RNA sequencing analysis. To study the effects of increased cardiomyocyte cell cycle activity, we administered neuregulin-1 (NRG1), a growth factor involved in cardiac development. RESULTS: PL induced an increase in CCA, with subsequent decline of CCA (sham/PL at 4 weeks: 0.14%/0.83%; P = .04 and 8 weeks: 0.00%/0.00%; P = .484) and cardiac function (cardiac index: control/PL 4 weeks: 4.41/3.29; P = .468 and 8 weeks: 3.57/1.44; P = .024). RNA sequencing analysis revealed delayed maturation and increased CCA pathways. NRG1 stimulated CCA (PL vehicle/NRG1 at 2 weeks: 0.62%/2.28%; P = .003), improved cardiac function (cardiac index control vs vehicle/NRG1 at 2 weeks: 4.21 vs 3.07/4.17; P = .009/.705) and postponed fibrosis (control vs vehicle/NRG1 at 4 weeks: 1.66 vs 4.82%/2.97%; P = .009/.078) in RV PL rats during childhood. CONCLUSIONS: RV PL during growth induces a transient CCA increase. Further CCA stimulation improves cardiac function and delays fibrosis. This proof-of-concept study shows that stimulation of CCA can improve RV adaptation to PL in the postnatal developing heart and might provide a new approach to preserve RV function in patients with congenital heart disease.

Association between glycated hemoglobin and ambulatory blood pressure or heart rate in hypertensive patients. / é«˜è¡€åŽ‹æ‚£è€ ç³–åŒ–è¡€çº¢è›‹ç™½ä¸ŽåŠ¨æ€è¡€åŽ‹åŠå¿ƒçŽ‡çš„ç›¸å ³æ€§.

OBJECTIVES: To determine the association between glycosylated hemoglobin (HbA1c) and ambulatory blood pressure or heart rate in hypertensive patients. METHODS: A total of 585 patients, who performed ambulatory blood pressure monitoring (ABPM) from September 2018 to April 2019 in Xiangya Hospital, Central South University, were enrolled and assigned into 2 groups (470 in a hypertensive group and 115 in a normal group). HbA1c levels were compared. According to the HbA1c level, the hypertensive group was divided into 2 subgroups: A high HbA1c group (HbA1c≥6.1%, n=142) and a normal HbA1c group (HbA1c<6.1%, n=328). Whole basic data and ABPM parameter were compared among the groups. Pearson/Spearman correlation analysis was applied to study the association between HbA1c and BPV. Multivariate logistic regression was used to explore the influential factors for HbA1c (≥6.1%) and continuous increase of HbA1c in different hypertensive populations, respectively. RESULTS: The hypertensive group had higher HbA1c level than the normal group [(6.1±1.3)% vs (5.1±1.7)%, P<0.05]. In hypertensive patients, nocturnal systolic blood pressure [(131.1±19.2) mmHg vs (122.5±19.2) mmHg], nocturnal systolic blood pressure load [62.5% (15.5%-100%) vs 28.6% (0-75%)], and daytime heart rate [(74.3±11.6) min-1 vs (71.2±11.4) min-1] of the high HbA1c group were higher than those in the normal HbA1c group (all P<0.05). Pearson/Spearman correlation analysis showed that HbA1c was positively correlated with systolic blood pressure and blood pressure load (both P<0.05). Logistic regression analysis showed that nocturnal systolic pressure load was the risk factor for the increase of HbA1c level (OR=1.025, 95% CI 1.003 to 1.048, P<0.05). Multiple linear regression showed that nocturnal systolic pressure load was still positively correlated with HbA1c in total, tertiary, and hypertensive patients without treatment (ß=0.155, ß=0.171, ß=0.384, respectively, all P<0.05). CONCLUSIONS: In hypertensive patients, HbA1c is positively correlated with ambulate blood pressure, blood pressure load, and heart rate, and it has no correlation with blood pressure variability, heart rate variability, or morning blood pressure.

Increased ambulatory arterial stiffness index and blood pressure load in normotensive obese patients.

OBJECTIVES: It has been shown that blood pressure (BP) values measured in obese subjects are higher than the individuals with normal weight, even in normotensive limits. However, data concerning the Ambulatory Arterial Stiffness Index (AASI) and blood pressure load in normotensive obese subjects is lacking. This study was aimed to compare the ambulatory arterial stiffness index and blood pressure load in normotensive obese and healthy controls. METHODS: One hundred normotensive obese and one hundred normal weight subjects were included in this study. All subjects underwent 24-hour ambulatory blood pressure monitoring. Ambulatory arterial stiffness index was calculated from 24-hour ambulatory blood pressure monitoring records. Ambulatory arterial stiffness index was defined as one minus the regression slope of unedited 24-h diastolic on systolic blood pressures. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) load values were calculated from 24-hour ambulatory blood pressure monitoring analysis. RESULTS: Ambulatory arterial stiffness index of the obese subjects was significantly higher than the healthy controls (0.48±0.2 vs. 0.33±0.11, p<0.001). 24-hours systolic blood pressure and diastolic blood pressure loads were significantly higher in obese subjects. Logistic regression analysis revealed that body mass index (BMI) was an independent predictor for an abnormal ambulatory arterial stiffness index (≥0.50) (OR: 1.137, 95% CI: 0.915-1.001, p=0.004). CONCLUSION: Blood pressure load and ambulatory arterial stiffness index are increased in normotensive obese patients. Moreover, body mass index is an independent predictor for an abnormal ambulatory arterial stiffness index. Our results indicate that obese subjects are at higher risk for future cardiovascular events despite normal office BP levels.

Blood Pressure Load: An Effective Indicator of Systemic Circulation Status in Individuals With Acute Altitude Sickness.

Background: Acute high altitude (HA) exposure results in blood pressure (BP) variations in most subjects. Previous studies have demonstrated that higher BP is potentially correlated with acute mountain sickness (AMS). The BP load may be of clinical significance regarding systemic circulation status. Objectives: This study aimed to examine HA-induced BP changes in patients with AMS compared to those in healthy subjects. Further, we provided clinical information about the relationship between variations in 24-h ambulatory parameters (BP level, BP variability, and BP load) and AMS. Methods: Sixty-nine subjects were enrolled and all participants ascended Litang (4,100 m above sea level). They were monitored using a 24-h ambulatory blood pressure device and underwent echocardiography within 24 h of altitude exposure. The 2018 Lake Louise questionnaire was used to evaluate AMS. Results: The AMS group comprised more women than men [15 (65.2%) vs. 13 (28.3%), P < 0.001] and fewer smokers [4 (17.4%) vs. 23 (50.0%), P = 0.009]. The AMS group exhibited significant increases in 24-h BP compared to the non-AMS group (24-h SBP variation: 10.52 ± 6.48 vs. 6.03 ± 9.27 mmHg, P = 0.041; 24-h DBP variation: 8.70 ± 4.57 vs. 5.03 ± 4.98 mmHg, P = 0.004). The variation of mean 24-h cBPL (cumulative BP load) (mean 24-h cSBPL: 10.58 ± 10.99 vs. 4.02 ± 10.58, P = 0.016; 24-h mean cDBPL: 6.03 ± 5.87 vs. 2.89 ± 4.99, P = 0.034) was also obviously higher in AMS subjects than in non-AMS subjects after HA exposure. 24-h mean cSBPL variation (OR = 1.07, P = 0.024) and 24-h mean cDBPL variation (OR = 1.14, P = 0.034) were independent risk factors of AMS. Moreover, variation of 24-h mean cSBPL showed a good correlation with AMS score (R = 0.504, P < 0.001). Conclusions: Our study demonstrated that patients with AMS had higher BP and BP load changes after altitude exposure than healthy subjects. Excessive BP load variations were associated with AMS. Thus, BP load could be an effective indicator regarding systemic circulation status of AMS.

Association between glycated hemoglobin and ambulatory blood pressure or heart rate in hypertensive patients / 中南大学学报(医学版)

OBJECTIVES@#To determine the association between glycosylated hemoglobin (HbA1c) and ambulatory blood pressure or heart rate in hypertensive patients.@*METHODS@#A total of 585 patients, who performed ambulatory blood pressure monitoring (ABPM) from September 2018 to April 2019 in Xiangya Hospital, Central South University, were enrolled and assigned into 2 groups (470 in a hypertensive group and 115 in a normal group). HbA1c levels were compared. According to the HbA1c level, the hypertensive group was divided into 2 subgroups: A high HbA1c group (HbA1c≥6.1%, @*RESULTS@#The hypertensive group had higher HbA1c level than the normal group [(6.1±1.3)% vs (5.1±1.7)%, @*CONCLUSIONS@#In hypertensive patients, HbA1c is positively correlated with ambulate blood pressure, blood pressure load, and heart rate, and it has no correlation with blood pressure variability, heart rate variability, or morning blood pressure.

Static Tactile Sensing for a Robotic Electronic Skin via an Electromechanical Impedance-Based Approach.

Tactile sensing is paramount for robots operating in human-centered environments to help in understanding interaction with objects. To enable robots to have sophisticated tactile sensing capability, researchers have developed different kinds of electronic skins for robotic hands and arms in order to realize the 'sense of touch'. Recently, Stanford Structures and Composites Laboratory developed a robotic electronic skin based on a network of multi-modal micro-sensors. This skin was able to identify temperature profiles and detect arm strikes through embedded sensors. However, sensing for the static pressure load is yet to be investigated. In this work, an electromechanical impedance-based method is proposed to investigate the response of piezoelectric sensors under static normal pressure loads. The smart skin sample was firstly fabricated by embedding a piezoelectric sensor into the soft silicone. Then, a series of static pressure tests to the skin were conducted. Test results showed that the first peak of the real part impedance signal was sensitive to static pressure load, and by using the proposed diagnostic method, this test setup could detect a resolution of 0.5 N force. Numerical simulation methods were then performed to validate the experimental results. The results of the numerical simulation prove the validity of the experiments, as well as the robustness of the proposed method in detecting static pressure loads using the smart skin.

[Effect of acupuncture at Renying (ST 9) on blood pressure in patients with ischemic stroke complicated with essential hypertension].

OBJECTIVE: To observe the effect of acupuncture at Renying (ST 9) on morning blood pressure, daytime peak blood pressure and 24-hour blood pressure load in patients with ischemic stroke complicated with essential hypertension. METHODS: A total of 80 patients (3 cases dropped off) were randomized into an observation group (39 cases) and a control group (38 cases). Xingnao Kaiqiao acupuncture and nifedipine were given in the control group. On the basis of treatment in the control group, acupuncture at Renying (ST 9) was applied in the observation group, once a day, 6 times a week for 4 weeks. The changes of morning blood pressure, daytime peak blood pressure and blood pressure load were observed before and after treatment in the two groups. RESULTS: Compared before treatment, morning blood pressure, daytime peak blood pressure and blood pressure load after treatment were reduced in the two groups (all P<0.05). The change of morning systolic pressure in the observation group was not significant as compared with that in the control group (P>0.05); the changes of morning diastolic pressure, daytime peak blood pressure and blood pressure load in the observation group were larger than those in the control group (all P<0.05). CONCLUSION: On the basis of Xingnao Kaiqiao acupuncture and nifedipine, acupuncture at Renying (ST 9) can effectively reduce morning blood pressure, daytime peak blood pressure and blood pressure load in patients with ischemic stroke complicated with essential hypertension.

[Relationship between systolic blood pressure load and sleep stability in patients with essential hypertension].

Objective: To explore the relationship between blood pressure load and sleep stability in hypertensive patients by cardiopulmonary coupling monitoring (CPC) and 24-hour ambulatory blood pressure monitoring. Methods: One hundred and fifty-five patients with essential hypertension were divided into high load group and low load group according to whether the blood pressure load was higher than 50%. The relationship between sleep stability and systolic blood pressure load was analyzed by logistic regression. Results: After adjusting for sex, age and body mass index (BMI), logistic regression analysis showed that stable sleep was the protective factor (OR=0.736,P=0.047) for the decrease of nocturnal blood pressure load, and unstable sleep was the risk factor for increasing day time blood pressure load (OR=1.336, P=0.037) in patients with hypertension. Conclusions: The effect of sleep stability on blood pressure load is different between day and night. Stable sleep is the protective factor of nocturnal systolic blood pressure load decrease, and unstable sleep is the harmful factor of daytime systolic blood pressure load increase. Increasing sleep stability helps to reduce systolic blood pressure load.