Blood Pressure Curve Research Articles

J-Curve Phenomenon—Current Understanding and Clinical Implications

J-curve can be defined as an increase in event rates when the blood pressure (BP) goes below a particular level. Now that we have safe and powerful drugs available for treatment of hypertension, it has become possible to bring down the BP to very low levels. However, the concept of “lower is better” is now being questioned. Trials looking at J-curve have given conflicting results. Probably, there is no J-curve for systolic BP. J-curve for stroke and renal end points is also debatable. It is in patients with significant obstructive coronary artery disease that there are data for a J curve for diastolic BP. In such patients, we should gradually titrate the dose of drugs, carefully watching for increasing angina. Isolated systolic hypertension (ISH) is another situation wherein care has to be taken when aggressively reducing systolic BP. Even here, there are questions to be answered. The low diastolic BP could be a marker of increased aortic stiffness. Or, the low diastolic BP may be due to other associated comorbid conditions. The fear of J-curve should not lead to undertreatment and thus deny patients the benefit of BP reduction.

Arterial Stiffness and Trace Elements in Apparently Healthy Population- A Cross-sectional Study.

Stiffening of arteries is a natural ageing process. Any diseases/disorders or risk factors that escalate oxidative stress, microvascular inflammation and endothelial damage may promote to premature vascular stiffening. Any imbalance in these trace element levels may independently contribute to the changes in the components in the arterial wall and thus, arterial stiffness via one or more mechanisms. To evaluate the severity of arterial stiffness in apparently healthy population and also to evaluate role of various risk factors and trace elements in the severity of arterial stiffness. Male and female subjects living in urban and rural areas of Nellore district, Andhra Pradesh, India, between 20-60 years, apparently normal as judged by the clinician basing on clinical and laboratory findings, were studied. Carotid-Femoral Pulse Wave Velocity (cf-PWV) a marker of arterial stiffness was assessed using non-invasive blood pressure curve monitoring (periscope). Furthermore, we also estimated serum levels of Copper (Cu), Zinc (Zn), Selenium (Se), chromium (Cr), Aluminium (Al), silicon (Si), Manganese (Mn), Molybdenum (Mb), Vanadium (Vn) and lead (Pb) using atomic absorption spectrophotometer. ANOVA and Chi-Square test were used to study the clinical correlations between severity of arterial stiffness, risk factors and trace elements. A total of 737 apparently healthy subjects participated in this cross-sectional study. Of the total 542 (73.5%) were from rural and the remaining 195 (26.5%) were living in urban areas, 328 (44.5%) were males, and 409 (55.5%) were females. A 63.5% (468/737) had normal arterial stiffness followed by 14.5% (107/737) with mild stiffness, 7% (57/737) had moderate stiffness and 14.2% (105/737) had severe arterial stiffness. Smoking, alcohol, blood pressures, fasting blood sugar, and total cholesterol, Cu, Al and Vn correlated (p<0.05) with different grades of arterial stiffness. A 36.5% had high arterial stiffness despite being apparently healthy. Smoking, alcohol, blood pressures, fasting blood sugars, and total cholesterol, Cu, Al and Vn could have contributed for such an abnormality. Caution has to be executed while understanding the study results since the pathophysiological process is complex.

Hypertension and chronic kidney disease: respective contribution of mean and pulse pressure and arterial stiffness.

Hypertension (HTN) in chronic kidney disease (CKD) is influenced by blood pressure (BP) and the progression of CKD, including hemodialysis and renal transplantation. To date, the efficacy of antihypertensive drug strategies has chiefly been assessed by measuring steady-state systolic, diastolic and mean arterial pressures (MAP). However, recently elucidated features of the BP curve have highlighted other important goals, that is, the specific roles of pulse pressure (PP), arterial stiffness, pulse wave velocity (PWV) and wave reflections as potentially deleterious factors affecting the progression of HTN and CKD. Pharmacological strategies to date have included progressive withdrawal of alpha-blocking agents; efficacy of beta-blockers for coronary prevention; use of angiotensin blockade in HTN with glomerular injury, using angiotensin-converting enzyme inhibition or receptor blockade, as mono but never double-blockade, to avoid major complications; development of combination therapies with diuretics and/or calcium channel blockers. Nowadays, most clinical trials show that SBP, DBP and MAP-lowering is an effective strategy, although results no longer show preference for any specific drug class.Studies of arterial stiffness in CKD have become crucial. In older individuals, PWV is considerably elevated. The 'stiffness gradient' disappears or is inverted (normally, aortic PWV is lower than brachial PWV). Despite BP-lowering, PP is insufficiently dampened, thus promoting microcirculatory damage, progression of arterial calcifications and disturbed wave reflections, which all increase the risk of mortality. In the absence of effective hemodialysis or graft, increased arterial stiffness is therefore a major cardiovascular risk factor in CKD.

FPGA controlled artificial vascular system

Abstract Monitoring the oxygen saturation of an unborn child is an invasive procedure, so far. Transabdominal fetal pulse oximetry is a promising method under research, used to estimate the oxygen saturation of a fetus noninvasively. Due to the nature of the method, the fetal information needs to be extracted from a mixed signal. To properly evaluate signal processing algorithms, a phantom modeling fetal and maternal blood circuits and tissue layers is necessary. This paper presents an improved hardware concept for an artificial vascular system, utilizing an FPGA based CompactRIO System from National Instruments. The experimental model to simulate the maternal and fetal blood pressure curve consists of two identical hydraulic circuits. Each of these circuits consists of a pre-pressure system and an artificial vascular system. Pulse curves are generated by proportional valves, separating these two systems. The dilation of the fetal and maternal artificial vessels in tissue substitutes is measured by transmissive and reflective photoplethysmography. The measurement results from the pressure sensors and the transmissive optical sensors are visualized to show the functionality of the pulse generating systems. The trigger frequency for the maternal valve was set to 1 per second, the fetal valve was actuated at 0.7 per second for validation. The reflective curve, capturing pulsations of the fetal and maternal circuit, was obtained with a high power LED (905 nm) as light source. The results show that the system generates pulse curves, similar to its physiological equivalent. Further, the acquired reflective optical signal is modulated by the alternating diameter of the tubes of both circuits, allowing for tests of signal processing algorithms.

Classifying individuals based on a densely captured sequence of vital signs: An example using repeated blood pressure measurements during hemodialysis treatment

Electronic Health Records (EHRs) present the opportunity to observe serial measurements on patients. While potentially informative, analyzing these data can be challenging. In this work we present a means to classify individuals based on a series of measurements collected by an EHR. Using patients undergoing hemodialysis, we categorized people based on their intradialytic blood pressure. Our primary criteria were that the classifications were time dependent and independent of other subjects. We fit a curve of intradialytic blood pressure using regression splines and then calculated first and second derivatives to come up with four mutually exclusive classifications at different time points. We show that these classifications relate to near term risk of cardiac events and are moderately stable over a succeeding two-week period. This work has general application for analyzing dense EHR data.

The Change of Circadian Pattern of Blood Pressure in Patients with Chronic Kidney Disease Before and After Kidney Transplantation in Cipto Mangunkusumo Hospital

Background: Circadian pattern of blood pressure (BP) is a 24 hours BP curve. Decreasing of BP 10–20% at night is called a dipper, while less than 10% a nondipper. Prevalence of hypertension and nondipper in Chronic Kidney Disease stage 5 on Dialysis (CKD 5D) are still very high. Kidney transplantation will improve BP and nondipper. Objective: To determine the change of dipper and nondipper, and the mean of 24 hours BP in CKD before, and one month after kidney transplantation. Methods: Design of the study is before and after design. 15 subjects CKD 5D before kidney transplantation, age 16–60 years, were conducted in Cipto Mangunkusumo Hospital during October to December 2014. 24 hours BP measurement were recorded with 24 hours Ambulatory Blood Pressure Monitoring in all subjects, before and one month after kidney transplantation. McNemar and t dependent test were used in statistical analysis. Results: Before kidney transplantation, 12 subjects were nondippers and 3 subjects were dippers. One month after kidney transplantation, all subjects (15) became nondippers. The decreasing of the mean of 24 hours systolic BP was found in all CKD one month after kidney transplantation, but statistically not significant (p > 0.05), while decreasing of the mean of 24 hours diastolic BP was statistically significant (p < 0.05). Conclusion: There were still no improvement in nondipper. There were a decrease in the mean of 24 hours systolic BP but not significant and a decrease in the mean of 24 hours diastolic BP significantly in patients one month after kidney transplantation.

PP.10.08

Objective: The change of blood pressure (BP) with age is well established. The trajectory of BP with ageing using repeated data is less studied, and difference in longitudinal BP curves could contribute the population specific rates of age-dependent outcomes. We investigated the trajectory of BP in serial measurements in ageing population sample in Russia. Design and method: The representative population samples of men and women aged 45–69 years at baseline were examined in 2003/05 in Novosibirsk (Russia) and re-examined 3 years later (aged 48–72 years, response rate = 77%) as part of the HAPIEE Project. Two types of analyses were made: (i) cross-sectional analyses of BP vs. age, and (ii) longitudinal analyses of repeated measurements of BP in 5564 persons with two repeated measurements over a mean 3.1 (SD 0.7) year follow-up. The difference (DIFF) in BP values between two examinations was calculated. Results: In cross-sectional analyses of re-examination data, both SBP and DBP increased with age (b = 0.882 and b = 0.093, respectively, both p-values < 0.001). In longitudinal analyses over the follow up, the mean systolic (SBP) and diastolic blood pressure (DBP) increased by 5.3 and 1.5 mm Hg, respectively. The increases in SBP were similar in men and women but changes of DBP in men were not statistically significant. After restricting analysis to those not receiving antihypertensive treatment, SBP trajectory remained consistently upward and DBP trajectory became insignificantly downward. The curves of both SBP DIFF and DBP DIFF were decreasing (b = -0.191, p < 0.001 and b = -0.053, p = 0.021, respectively). Conclusions: In this Russian population sample of middle aged and older persons, SBP increased with age in both cross-sectional and longitudinal analyses. However, association of longitudinal DBP with age was not statistically significant. These findings reflect the limitations of BP control, and may suggest the peculiarities of BP gradient with ageing in the Siberian population; this might contribute the high rates of age-dependent outcomes.

Doppler spectrum of intrarenal blood flow and circadian blood pressure rhythm in hypertensive patients

The aim of the study was to assess relationship of results of 24-h ambulatory blood pressure (24-h ABPM) monitoring on the parameters of renal hemodynamic in hypertensive patients. The renal hemodynamic was evaluated by ultrasound Doppler. The glomerular filtration rate (on a clearance of endogenous creatinine) has been measured out before and after the acute oral protein loading for evaluation of renal functional reserve. The results of one-way ANOVA showed, that the «blood pressure load index» – areas under systolic and diastolic blood pressure curves and systolic and diastolic blood pressure-time index 24 h' influenced extremely negatively on renal pulsating index. These data and their values of 24-h ABPM may be useful for the clinical assessment of hypertensive patient by identifying those at high risk for the presence of renal injury.

Comparison of the effects of bimatoprost and a fixed combination of latanoprost and timolol on 24-hour blood and ocular perfusion pressures: the results of a randomized trial.

BackgroundTo compare the effect of bimatoprost and the fixed combination latanoprost-timolol (LTFC) on 24-hour systolic (SBP) and diastolic (DBP) blood pressure and on 24-hour ocular perfusion pressure (OPP).Methods200 patients with glaucoma or ocular hypertension, controlled on the unfixed combination of latanoprost and timolol or eligible for dual therapy being not being fully controlled on monotherapy were enrolled in a randomized, double-masked, placebo-controlled, multicentre clinical trial. They were randomized to LTFC (8 a.m.) or bimatoprost (8 p.m.) and received 24-hour IOP curve at baseline, 6 and 12 weeks (supine and sitting position IOPs were recorded at 8 p.m., midnight, 5 a.m., 8a.m., noon and 4 p.m.). Holter 24-hour blood pressure curve was obtained between weeks 2 and 12. SBP, DBP, OPP were calculated and compared with ANOVA. Rates of diastolic OPP (DPP) ≤50, ≤40, ≤30 mmHg in the 2 groups were calculated and compared using Fisher’s test.ResultsMean baseline SBP and DBP were 136.5 ± 18.3 vs 134.2 ± 20.1 mmHg (p = 0.1) and 79.1 ± 10.2 vs 78.2 ± 10.1 mmHg (p = 0.4) in the bimatoprost and LTFC groups respectively. Holter SBP was significantly higher for bimatoprost (135.1 mmHg vs 128.1 mmHg, p = 0.04), while no statistically significant difference in DBP was found. DPP was similar in the 2 groups, and proportions of patients with at least one value of the 24-hour curve ≤50, ≤40, ≤30 mmHg were 94%, 86%, 41% respectively.ConclusionsBimatoprost and LTFC had similar DBPs and OPPs; SBP was significantly lower with LTFC. In this study, the percentage of “dippers” was considerably higher than the one described in previous studies on the role of perfusion pressure in glaucoma.Trial registrationNCT02154217, May 21, 2014.

Effects of a contraceptive containing drospirenone and ethinylestradiol on blood pressure, metabolic profile and neurohumoral axis in hypertensive women at reproductive age

The use of combined oral contraceptives is widespread among hypertensive women despite being associated with increased cardiovascular risk. Contraceptives containing drospirenone, which has antimineralocorticoid properties, may have a positive or neutral effect on neurohumoral activation and metabolic homeostasis of hypertensive women at reproductive age. ObjectivesTo evaluate the effect of combined oral contraceptive containing drospirenone+ethinylestradiol on the systemic blood pressure, metabolic variables and neurohumoral axis in hypertensive women in reproductive age. DesignProspective controlled trial with 56 hypertensive women allocated in two groups: 30 volunteers under oral combined contraceptive use and 26 volunteers using non-hormonal contraceptive methods. Subjects were tested before the introduction of the contraceptive method and 6 months after its use. For data acquisition, we used continuous non-invasive beat-to-beat blood pressure curve recordings and, for the biochemical and hormonal analyses two blood samples were obtained. Student's t test was used to determine differences between groups and moments and p<0.05 was considered statistically significant. ResultsComparing antropometric and blood pressure measurements, cardiac sympatho-vagal modulation, baroreceptor sensitivity, metabolic and neurohumoral axis variables between baseline and after 6 months, no significant difference was detected in each group or between groups. Except serum triglyceride levels which increased in the group of women using EE+DRSP after 6 months of use. ConclusionA contraceptive containing 20mcg of ethinyl estradiol and 3mg of drospirenone causes no significant changes in clinical and autonomic parameters, metabolic variables and neurohumoral axis of hypertensive women.

Estenosis pulmonar pura

La ayuda invalorable de los nuevos procedimientos de investigación cardiológica nos ha permitido realizar un mejor estudio de las diferentes anomalías cardíacas. Entre ellos juega un papel importante el cateterismo intracardíaco, el que nos permite determinar datos tales como la gasometría y las curvas de presiones; la cineangiocardiografía puede detectar pequeñas anomalías que escapan incluso al cateterismo intracardíaco y el gran auge que tiene en nuestros días la cirugía cardíaca por medio de la circulación extracorpórea. Así, tenemos que, revisando los estudios realizados en décadas pasadas sobre todo en lo que se refiere a cardiopatías congénitas y entre ellas la Estenosis Pulmonar Pura encontramos conceptos y porcentajes que han variado. Desde Morgagni en 1791, que describió el primer caso de estenosis pulmonar valvular, pasando por Abbot (9 casos), Brock y Campbell (18 casos) Abrahams y Wood (26 casos) Kírklín y col. (100 casos) y otros, llegamos a 1961 en que Sherf realiza un estudio en forma exhaustiva de esta anomalía con la ayuda de la angiocardiografía. Por lo anterior se puede apreciar que la estenosis pulmonar aislada no es de excepcional rareza (63) como se pensó en un principio. Conforme se ha ido perfeccionando los métodos de diagnóstico auxiliares se ha podido demostrar que más bien es frecuente; ocupando el tercer o cuarto lugar entre las cardiopatías congénitas. El propósito del presente trabajo es relatar el estudio de 22 casos de Estenosis Pulmonar Pura, que fueron vistos, en el Servicio de Cardiología del Hospital Militar Central entre los años 1960-1964.

Continuous blood pressure assessment from a photoplethysmographic signal with Deep Belief Networks (LB674)

Continuous blood pressure assessment from a photoplethysmographic signal with Deep Belief Networks Vicent J. Ribas Ripoll PhD; Anna Wojdel PhD; Anna Sáez de Tejada Cuenca; Juan C. Ruiz‐Rodríguez, MD; Adolf Ruiz‐Sanmartín, MD; Miriam de Nadal MD, PhD; Enrique Romero PhD; Alfredo Vellido PhD A prospective study was conducted at a critical care department and post‐anesthesia care unit of a university teaching hospital in Barcelona, Spain. The study recruited 707 patients with invasive BP and finger PPG waves over a period of 26 months. Exclusion criteria were presence of major arrhythmia, immediate death condition and disturbances in the arterial or PPG curve morphology. For each patient we automatically recorded the systolic blood pressure (SBP), mean arterial pressure (MAP), diastolic blood pressure (DBP) and PPG curve for 30 minutes. The PPG signal was further processed to obtain a set of features that were used to construct a Deep Belief Network with Gaussian Restricted Boltzmann Machine (DBN‐RBM). The available dataset was split into three subsets (Training, Validation and Testing). The training and validation datasets included 85% of data and the testing dataset included 15% of the available data. The regression error was assessed through a Bland‐Altman analysis and the AAMI standard. The mean prediction error were ‐2.98+‐19.35 mmHg for SBP, ‐3.38+‐10.35 mmHg for MAP and 3.65+‐8.69 mmHg for DBP.The results obtained are promising for the assessment of MAP and DBP with DBN‐RBM. Further research and clinical validation are needed to bring this technology to standard medical practice.Grant Funding Source: Supported by Shockomics (FP7 framework)

Cardiothoracic impedance does not reflect beat‐to‐beat changes in cardiac stroke volume during mild lower body negative pressure (707.1)

Background: Variability in cardiac stroke volume (SVV) has been proposed as a clinical tool to assess the magnitude of acute hemorrhage. We investigated how three non‐invasive methods represent the beat‐to‐beat changes of cardiac stroke volume (SV).Methods: Ten healthy subjects underwent mild simulated hemorrhage through lower body negative pressure (LBNP) at ‐30 mmHg after a five minutes resting period at baseline. SV beat‐to‐beat was estimated simultaneously by three non‐invasive methods: Ultrasound Doppler (SV_usd), finger arterial blood pressure curve (SV_bpc) and cardiothoracic impedance (SV_imp). SVV was calculated at respiratory frequency between 0.15 and 0.40 Hz from spectral analysis. The median and 95% confidence intervals (CI) were calculated by Hodges‐Lehman’s estimates from epochs of 120 seconds at baseline and at ‐30 mmHg of LBNP. Statistical differences were calculated by Wilcoxon matched‐pairs signed rank test.Results: SVV_usd and SVV_bpc decreased at ‐30 mmHg LBNP to 32% (18%, 47%) and 32% (21%, 43%) of baseline variability. In contrast, SVV_imp was unchanged at ‐30 mmHg (88% (42%, 182%), p=0.82) relative to baseline.Conclusion: Cardiac stroke volume estimated by Ultrasound Doppler and finger arterial blood pressure curve reflect the same variations beat‐to‐beat during simulated hemorrhage. Cardiothoracic impedance does not reflect beat‐to‐beat changes in SV.Grant Funding Source: The Research Council of Norway

Differential effect of beetroot bread on postprandial DBP according to Glu298Asp polymorphism in the eNOS gene: a pilot study

Our objective was to investigate whether the presence of Glu298Asp polymorphism in the endothelial NO synthase (eNOS) gene differentially affects the postprandial blood pressure response to dietary nitrate-rich beetroot bread. A randomised, single-blind, controlled, crossover acute pilot study was performed in 14 healthy men (mean age: 34±9 years) who were retrospectively genotyped for Glu298Asp polymorphism (7GG; T carriers 7). Volunteers were randomised to receive 200 g beetroot-enriched bread (1.1 mmol nitrate) or control bread (no beetroot; 0.01 mmol nitrate) on two separate occasions 10 days apart. Baseline and incremental area under the curve of blood pressure and NOx (nitrate/nitrite) were measured for a 6-h postprandial period. A treatment × genotype interaction was observed for diastolic blood pressure (P<0.02), which was significantly lower in T carriers (P<0.01) after consumption of beetroot bread compared with control bread. No significant differences were observed in the GG group. The beneficial diastolic blood pressure reduction was observed only in the T carriers of the Glu298Asp polymorphism in the eNOS gene after consumption of nitrate-rich beetroot bread. These data require confirmation in a larger population group.

Blood Pressure Load Does Not Add to Ambulatory Blood Pressure Level for Cardiovascular Risk Stratification

Experts proposed blood pressure (BP) load derived from 24-hour ambulatory BP recordings as a more accurate predictor of outcome than level, in particular in normotensive people. We analyzed 8711 subjects (mean age, 54.8 years; 47.0% women) randomly recruited from 10 populations. We expressed BP load as percentage (%) of systolic/diastolic readings ≥135/≥85 mm Hg and ≥120/≥70 mm Hg during day and night, respectively, or as the area under the BP curve (mm Hg×h) using the same ceiling values. During a period of 10.7 years (median), 1284 participants died and 1109 experienced a fatal or nonfatal cardiovascular end point. In multivariable-adjusted models, the risk of cardiovascular complications gradually increased across deciles of BP level and load (P<0.001), but BP load did not substantially refine risk prediction based on 24-hour systolic or diastolic BP level (generalized R(2) statistic ≤0.294%; net reclassification improvement ≤0.28%; integrated discrimination improvement ≤0.001%). Systolic/diastolic BP load of 40.0/42.3% or 91.8/73.6 mm Hg×h conferred a 10-year risk of a composite cardiovascular end point similar to a 24-hour systolic/diastolic BP of 130/80 mm Hg. In analyses dichotomized according to these thresholds, increased BP load did not refine risk prediction in the whole study population (R(2)≤0.051) or in untreated participants with 24-hour ambulatory normotension (R(2)≤0.034). In conclusion, BP load does not improve risk stratification based on 24-hour BP level. This also applies to subjects with normal 24-hour BP for whom BP load was proposed to be particularly useful in risk stratification.

Effects of a contraceptive containing drospirenone and ethinyl estradiol on blood pressure and autonomic tone: a prospective controlled clinical trial

BackgroundThe use of combined oral contraceptives has been associated with an increased risk of adverse cardiovascular events. Whether these drugs alter cardiac autonomic nervous system control is not completely determined. ObjectiveTo evaluate the effect of a contraceptive containing 20mcg of ethinyl estradiol and 3mg of drospirenone on the heart rate variability, baroreflex sensitivity and blood pressure of healthy women. Study designProspective controlled trial with 69 healthy women allocated in two groups: 36 volunteers under oral combined contraceptive use and 33 volunteers using of non-hormonal contraceptive methods. Subjects were tested before the introduction of the contraceptive method and 6 months after its use. For data acquisition, we used continuous non-invasive beat-to-beat blood pressure curve recordings. Multiple ANOVA was used to determine differences between groups and moments and p< 0.05 was considered statistically significant. ResultsAt baseline, there were no differences in demographic and autonomic parameters between groups. Comparing cardiac sympatho-vagal modulation, baroreceptor sensitivity and blood pressure measurements between baseline and after 6 months, no significant difference was detected in each group or between groups. ConclusionA contraceptive containing 20mcg of ethinyl estradiol and 3mg of drospirenone causes no significant changes in clinical, hemodynamic and autonomic parameters of normal women.

Donor hemodynamic profile presages graft survival in donation after cardiac death liver transplantation

Obligatory exposure to a period of warm ischemia is the defining feature of liver allografts from donation after cardiac death (DCD) donors. We explored novel methods for characterizing the dynamic aspects of donor warm ischemia that might be useful in assessing organ quality. The hemodynamic profile during donor warm ischemia was retrospectively studied for 110 Maastricht category III DCD donors. Three methods were used to summarize the hemodynamic changes after extubation: (1) the area under the systolic blood pressure curve (AUCSBP), (2) the slope of the systolic blood pressure regressed onto the time from extubation until cross-clamping, and (3) the slope of the systolic blood pressure regressed onto the time from extubation but calculated with only the values during the first 10 minutes after extubation (SBP10). Stepwise multivariate Cox models were created to study the association of these measures with graft survival. The duration of the donor warm ischemia time (23.6 ± 8.5 minutes) was not associated with graft survival (P = 0.35), although AUCSBP and SBP10 demonstrated significant associations (P = 0.02 and P = 0.05, respectively) in a univariate analysis. Multivariate regression models incorporating donor and recipient covariates indicated that among all covariates, SBP10 had the closest association with graft survival (hazard ratio = 1.08, P = 0.01). This association was even stronger when SBP10 was dichotomized into values above or below the median (-7.2 mm Hg/minute). Patients with SBP10s steeper than the median had an estimated 5-year graft survival rate of 76%, whereas patients with slopes less than the median had a 5-year survival rate of 45% (P < 0.007). In conclusion, the incorporation of novel methods for characterizing the donor warm ischemia time may help in selecting DCD liver allografts with favorable outcomes.

Relationship between 24-hour blood pressure rhythm and carotid scleratheroma in elderly patients with hypertension

Objeetive To investigate the relationship between 24-hour blood pressure rhythm and carotid scleratheroma in elderly patients with hypertension.Methods 193 elderly patients with hypertension were enrolled in the study and divided into study group (91 cases with carotid atherosclerosis) and control group (102 cases).All the patients were given 24h blood pressure rhythm examination.The characteristics of 24hour blood pressure rhythm was compared between the two groups.Results The 24h average systolic blood pressure(24h-SBP),24h average diastolic blood pressure (24h-DBP),24h average pulse pressure (24h-MBP) between the study group and the control group had no significant differences(P ＞ 0.05).The daytime average systolic blood pressure(d-SBP),diurnal mean diastolic blood pressure (d-DBP),diurnal average pulse pressure (d-MBP),nocturnal mean systolic blood pressure (n-SBP),nocturnal mean diastolic blood pressure(n-DBP),nocturnal mean pulse pressure(n-MBP) of the study group were significantly higher than those of the control group (t =16.92,24.68,6.16,12.87,11.59,6.35,all P ＜0.05).In study group,d-SBP,d-DBP,d-MBP were higher than n-SBP,n-DBP,n-MBP,the differences were statistically significant(F =73.61,P ＜ 0.01).The circadian blood pressure variability of the study group was more than 10％,the 24h ambulatory blood pressure curve graph of the study group was non-dipper curve.The circadian blood pressure variability of the control group was less than 5％,the 24h ambulatory blood pressure curve was dipper type curve.Conclusion The MBPS is strongly associated with carotid scleratheroma,and clinical treatment and study could derive from ABPM data analysis. Key words: Hypertension; Periodicity; Carotid artery diseases; Aged

C-reactive protein and its relation to high blood pressure in overweight or obese children and adolescents

OBJECTIVE To investigate the association between C-reactive protein (CRP) and high blood pressure (BP) in overweight or obese children and adolescents. METHODS Cross-sectional study with 184 overweight or obese children and adolescents aged from two to 18 years old, from April, 2009 to April, 2010. The classification of nutritional status used the body mass index (BMI). Based on the Centers for Disease Control and Prevention curve, individuals were classified as: overweight (BMI between the 85th-95th percentiles), obesity (BMI between 95th-97th percentiles) and severe obesity (BMI >97th percentile). Abnormal values were considered for systolic BP (SBP) and/or diastolic (DBP) if ≥90th percentile of the BP curve recommended for children and adolescents in the V Brazilian Guidelines on Hypertension, for waist circumference (WC) if ≥90th percentile of the curve established by the National Cholesterol Education Program, and for high sensitive CRP (hs-CRP) if >3mg/dL. To evaluate the association of inadequate values of CRP and the studied groups, chi-square test and analysis of variance were applied, using the Statistical Package for the Social Sciences version 17.0 and adopting a significance level of 5%. RESULTS Among the evaluated sample, 66.3% were female, 63.5%, non-white, 64.1% had severe obesity, 78.3% had altered WC and 70.6% presented high BP. There was a significant association of CRP high levels with altered WC and BMI ≥97th percentile. In adolescents, high CRP was related to high SBP. CRP mean values were higher in individuals with elevated SBP. CONCLUSIONS Inadequate values of hs-CRP were associated with severe obesity and high SBP in the studied population. These markers can be used to identify children and adolescents at higher risk for developing atherosclerosis.

Virtual arterial blood pressure feedback improves chest compression quality during simulated resuscitation

IntroductionQuality chest compressions (CC) are the most important factor in successful cardiopulmonary resuscitation. Adjustment of CC based upon an invasive arterial blood pressure (ABP) display would be theoretically beneficial. Additionally, having one compressor present for longer than a 2-min cycle with an ABP display may allow for a learning process to further maximize CC. Accordingly, we tested the hypothesis that CC can be improved with a real-time display of invasively measured blood pressure and with an unchanged, physically fit compressor. MethodsA manikin was attached to an ABP display derived from a hemodynamic model responding to parameters of CC rate, depth, and compression-decompression ratio. The area under the blood pressure curve over time (AUC) was used for data analysis. Each participant (N=20) performed 4 CPR sessions: (1) No ABP display, exchange of compressor every 2min; (2) ABP display, exchange of compressor every 2min; (3) no ABP display, no exchange of the compressor; (4) ABP display, no exchange of the compressor. Data were analyzed by ANOVA. Significance was set at a p-value<0.05. ResultsThe average AUC for cycles without ABP display was 5201mmHgs (95% confidence interval (CI) of 4804–5597mmHgs), and for cycles with ABP display 6110mmHgs (95% CI of 5715–6507mmHgs) (p<0.0001). The average AUC increase with ABP display for each participant was 20.2±17.4% 95 CI (p<0.0001). ConclusionsOur study confirms the hypothesis that a real-time display of simulated ABP during CPR that responds to participant performance improves achieved and sustained ABP. However, without any real-time visual feedback, even fit compressors demonstrated degradation of CC quality.