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1

The severity of coronary artery disease evaluated by central systolic pressure and fractional diastolic pressure  

OpenAIRE

Background: Central pulse pressure, pulse pressure index and fractional pulse pressure have been confirmed to be associated with increased risk of cardiovascular disease, but if the severity of cardiovascular disease, specifically for the coronary artery disease, is evaluated by central systolic pressure and fractional diastolic pressure has been not well studied. Aims: This study was designed to examine if central systolic pressure and fractional diastolic pressure could act as a predicting ...

Song-Tao An; Qi, Yan-yan; Li-Xia Wang

2010-01-01

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Proportional Relations Between Systolic, Diastolic and Mean Pulmonary Artery Pressure are Explained by Vascular Properties  

OpenAIRE

Recently, it was shown that proportional relationships exist between systolic, diastolic and mean pulmonary artery pressure (Psys, Pdia and Pmean) and that they are maintained under various conditions in both health and disease. An arterial-ventricular interaction model was used to study the contribution of model parameters to the ratios Psys/Pmean, and Pdia/Pmean. The heart was modeled by a time-varying elastance function, and the arterial system by a three-element windkessel model consistin...

Kind, Taco; Faes, Theo J. C.; Vonk-noordegraaf, Anton; Westerhof, Nico

2010-01-01

3

Increased response of diastolic blood pressure to exercise in patients with coronary artery disease: an index of latent ventricular dysfunction?  

OpenAIRE

OBJECTIVE--To determine whether an abnormal response of diastolic blood pressure during treadmill exercise stress testing correlated with the number of obstructed vessels and with left ventricular systolic function in patients with coronary artery disease. DESIGN--Diastolic blood pressure was measured invasively during exercise stress testing and coronary angiograms and left ventriculograms were obtained at rest in patients with coronary artery disease. The abnormal (> or = 15 mm Hg) diastoli...

Paraskevaidis, I. A.; Kremastinos, D. T.; Kassimatis, A. S.; Karavolias, G. K.; Kordosis, G. D.; Kyriakides, Z. S.; Toutouzas, P. K.

1993-01-01

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Abnormal shortened diastolic time length at increasing heart rates in patients with abnormal exercise-induced increase in pulmonary artery pressure  

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Full Text Available Abstract Background The degree of pulmonary hypertension is not independently related to the severity of left ventricular systolic dysfunction but is frequently associated with diastolic filling abnormalities. The aim of this study was to assess diastolic times at increasing heart rates in normal and in patients with and without abnormal exercise-induced increase in pulmonary artery pressure (PASP. Methods. We enrolled 109 patients (78 males, age 62 ± 13 years referred for exercise stress echocardiography and 16 controls. The PASP was derived from the tricuspid Doppler tracing. A cut-off value of PASP ? 50 mmHg at peak stress was considered as indicative of abnormal increase in PASP. Diastolic times and the diastolic/systolic time ratio were recorded by a precordial cutaneous force sensor based on a linear accelerometer. Results At baseline, PASP was 30 ± 5 mmHg in patients and 25 ± 4 in controls. At peak stress the PASP was normal in 95 patients (Group 1; 14 patients (Group 2 showed an abnormal increase in PASP (from 35 ± 4 to 62 ± 12 mmHg; P Conclusion The first and second heart sound vibrations non-invasively monitored by a force sensor are useful for continuously assessing diastolic time during exercise. Exercise-induced abnormal PASP was associated with reduced diastolic time at heart rates beyond 100 beats per minute.

Bombardini Tonino

2011-11-01

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Oscillometric measurement of systolic and diastolic blood pressures validated in a physiologic mathematical model  

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Full Text Available Abstract Background The oscillometric method of measuring blood pressure with an automated cuff yields valid estimates of mean pressure but questionable estimates of systolic and diastolic pressures. Existing algorithms are sensitive to differences in pulse pressure and artery stiffness. Some are closely guarded trade secrets. Accurate extraction of systolic and diastolic pressures from the envelope of cuff pressure oscillations remains an open problem in biomedical engineering. Methods A new analysis of relevant anatomy, physiology and physics reveals the mechanisms underlying the production of cuff pressure oscillations as well as a way to extract systolic and diastolic pressures from the envelope of oscillations in any individual subject. Stiffness characteristics of the compressed artery segment can be extracted from the envelope shape to create an individualized mathematical model. The model is tested with a matrix of possible systolic and diastolic pressure values, and the minimum least squares difference between observed and predicted envelope functions indicates the best fit choices of systolic and diastolic pressure within the test matrix. Results The model reproduces realistic cuff pressure oscillations. The regression procedure extracts systolic and diastolic pressures accurately in the face of varying pulse pressure and arterial stiffness. The root mean squared error in extracted systolic and diastolic pressures over a range of challenging test scenarios is 0.3 mmHg. Conclusions A new algorithm based on physics and physiology allows accurate extraction of systolic and diastolic pressures from cuff pressure oscillations in a way that can be validated, criticized, and updated in the public domain.

Babbs Charles F

2012-08-01

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Oscillometric measurement of systolic and diastolic blood pressures validated in a physiologic mathematical model  

OpenAIRE

Abstract Background The oscillometric method of measuring blood pressure with an automated cuff yields valid estimates of mean pressure but questionable estimates of systolic and diastolic pressures. Existing algorithms are sensitive to differences in pulse pressure and artery stiffness. Some are closely guarded trade secrets. Accurate extraction of systolic and diastolic pressures from the envelope of cuff pressure oscillations remains an open problem in biomedical engineering. Methods A new...

Babbs Charles F

2012-01-01

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Influence of the observer's level of experience on systolic and diastolic arterial blood pressure measurements using Doppler ultrasonography in healthy conscious cats.  

Science.gov (United States)

The objective of this study was to determine the influence of the observer's level of experience on within- and between-day variability, and the percentage of successful systolic (SAP) and diastolic arterial blood pressure (DAP) measurements obtained by Doppler ultrasonography (DU) in awake cats. For this purpose, six healthy conscious cats were used and four observers with different levels of training performed 144 SAP and DAP measurements on 4 days using DU. Measurements were recorded five consecutive times, and mean values were used for statistical analysis. Only the two most skilled observers - a PhD student in cardiology and a Dipl ECVIM-CA (cardiology) - had within- and between-day coefficients of variation (CVs) for SAP ?16% (13-16%). Conversely, the two less experienced observers - a fifth-year student and an assistant - had high between-day CVs (61% and 73%). For DAP, only the most experienced observer (Dipl ECVIM-CA) succeeded in 100% of the attempts, with within- and between-day CVs of 11% and 4%, respectively. Conversely, DAP could not be measured by the other three observers in 8%, 19% and 56% of attempts (from the highest to the lowest level of experience); therefore, the corresponding CV values could not be calculated. In conclusion, SAP may be assessed using DU in healthy awake cats with good repeatability and reproducibility by a well-trained observer. Measurement of DAP is more difficult than of SAP, and needs a longer training period, which represents one of the limitations of DU in cats. PMID:24782457

Gouni, Vassiliki; Tissier, Renaud; Misbach, Charlotte; Balouka, David; Bueno, Hanna; Pouchelon, Jean-Louis; Lefebvre, Hervé P; Chetboul, Valérie

2015-02-01

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Diastolic blood pressure influences cerebrovascular reactivity measured by means of 123I-iodoamphetamine brain single photon emission computed tomography in medically treated patients with occlusive carotid or middle cerebral artery disease  

International Nuclear Information System (INIS)

Impaired cerebrovascular reactivity (CVR) to vasodilating agents is a predictor of the onset and prognosis of ischemic stroke. It is realized that the CVR improves or worsens when measured periodically during the clinical course in medically treated patients with occlusive cerebrovascular disease. In these patients, we investigated the possible relationship between the interval change in CVR and that in systemic blood pressure (BP). Forty-two patients (14 females and 28 males, mean age±SD: 65.3±8.8 years) with severe stenosis or occlusion of the common carotid, internal carotid, or middle cerebral arteries repeatedly underwent single photon emission computed tomography (SPECT) studies using 123I-iodoamphetamine to measure cerebral blood flow (CBF) distribution and CVR at a more-than-6-month interval (mean±SD: 18.5±8.8 months). The CVR was separately estimated in cerebral hemispheres ipsilateral and contralateral to the most severe vascular lesion as the % increase in CBF after acetazolamide loading to CBF at rest. Systemic BP was measured four times at enrollment and the follow-up SPECT studies during resting and acetazolamide loading. Average BP at each SPECT study was an average of BP measurements during resting and acetazolamide loading. Interval changes in CVR were correlated with those in average systolic BP, average diastolic BP, and average mean arterial BP. The interval changes in CVR were significantly correlated with those in average diastolicelated with those in average diastolic BP in the ipsilateral hemisphere (y=0.71x+1.43, r2=0.11, p2=0.16, p123I-IMP SPECT was influenced by the diastolic BP at the SPECT studies. Monitoring diastolic BP is important to evaluate interval change in CVR. (author)

9

Reversal of diastolic flow in the middle cerebral artery of the fetus during the second half of pregnancy.  

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This study obtained data on 22 fetuses in whom reversal of diastolic flow in the middle cerebral artery (MCA) was seen. In 59% of cases there was normal heart function and in 28% there was isolated tricuspid valve regurgitation. The majority (73%) of cases presented with normal fetal anatomy and most (82%) had a normal amniotic fluid index and normal fetal growth. In all cases, Doppler results of the umbilical artery and vein were normal. Of the women, 65% were on no medication and 73% did not smoke during pregnancy. The reversal of diastolic flow in the MCA was seen temporarily in the majority of cases (for 2-30 min); however, in one case with rhesus factor disease and a rim of ascites, it was observed for a longer period (about 2 h) and on the following day, intrauterine demise was recorded. In most of the cases without structural malformations, the neonatal outcome was normal. We conclude that reversed diastolic flow in the MCA is a rare and usually transient event. In one of our cases prolonged reversed flow preceded intrauterine demise. Therefore, this may be an ominous sign and careful fetal surveillance should be undertaken when this observation is made. There are a few possible pathomechanisms of reversed diastolic flow in the MCA. In the majority of cases the cause of the observed phenomenon remains unknown, but an increased pressure in the right ventricle and possible tricuspid regurgitation should be considered. PMID:9201876

Respondek, M; Woch, A; Kaczmarek, P; Borowski, D

1997-05-01

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Relationship between occupational exposure to lead and local arterial stiffness and left ventricular diastolic function in individuals with arterial hypertension  

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Relationship between occupational exposure to lead and frequency of complications in persons with arterial hypertension has been poorly investigated. This study aimed at evaluation of the relationship between occupational exposure to lead and manifestation of an increased local arterial stiffness and left ventricular diastolic dysfunction. The studies included 105 men (mean age: 44.47 ± 9.12 years) with arterial hypertension, treated with hypotensive drugs: group I - men occupationally exposed to lead (n = 53), and group II - men not exposed to lead (n = 52). In echocardiographic examination, the left ventricular diastolic dysfunction was diagnosed significantly more frequently in group I than in group II. In eTracking examination mean values of stiffness parameter (?), augmentation index (AI) and one-point pulse wave velocity (PWV-?) were significantly higher and mean values of arterial compliance (AC) were significantly lower in group I than in group II. The logistic regression showed that in the group of persons with arterial hypertension occupationally exposed to lead a more advanced age, higher blood lead concentration and higher mean values of augmentation index represent independent risk factors of left ventricular diastolic dysfunction. The multifactorial regression showed that amongst persons with arterial hypertension occupationally exposed to lead higher blood zinc protoporphyrin concentration, a more advanced age and higher value of body mass index (BMInd higher value of body mass index (BMI) represent independent risk factors of an increased local arterial stiffness. In summary, we should note that in the group of persons with arterial hypertension occupationally exposed to lead the study has demonstrated a significantly more frequent manifestation of left ventricular diastolic dysfunction and an increase in local arterial stiffness. - Highlights: ? Amongst persons with AH exposed to Pb higher ZnPP represent independent risk factor of increased local arterial stiffness. ? Higher Pb-B represent independent risk factor of left ventricular diastolic dysfunction. ? The study has demonstrated a more frequent manifestation of left ventricular diastolic dysfunction in group exposed to Pb. ? Also, in this group the study has demonstrated a more frequent manifestation of increase in local arterial stiffness.

11

Association between intrarenal arterial resistance and diastolic dysfunction in type 2 diabetes  

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Full Text Available Abstract Background In comparison to the well established changes in compliance that occur at the large vessel level in diabetes, much less is known about the changes in compliance of the cardiovascular system at the end-organ level. The aim of this study was therefore to examine whether there was a correlation between resistance of the intrarenal arteries of the kidney and compliance of the left ventricle, as estimated by measurements of diastolic function, in subjects with type 2 diabetes. Methods We studied 167 unselected clinic patients with type 2 diabetes with a kidney duplex scan to estimate intrarenal vascular resistance, i.e. the resistance index (RI = peak systolic velocity-minimum diastolic velocity/peak systolic velocity and a transthoracic echocardiogram (TTE employing tissue doppler studies to document diastolic and systolic ventricular function. Results Renal RI was significantly higher in subjects with diastolic dysfunction (0.72 ± 0.05 when compared with those who had a normal TTE examination (0.66 ± 0.06, p Conclusion Increasing vascular resistance of the intrarenal arteries was associated with markers of diastolic dysfunction in subjects with type 2 diabetes. These findings are consistent with the hypothesis that vascular and cardiac stiffening in diabetes are manifestations of common pathophysiological mechanisms.

Matthews D Geoffrey

2008-05-01

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Coronary flow and left ventricular pressure during diastole in the anaesthetized dog.  

OpenAIRE

There is controversy about the effect of left ventricular pressure on resistance of the intramyocardial coronary vessels. In anaesthetized dogs the effect of left ventricular pressure on coronary flow during diastole was studied using an extracorporeal circulation and allowing the heart to contract and relax isovolumically. At constant coronary perfusion pressure of about 45 mmHg with maximal coronary vasodilatation, produced by dipyridamole, increases in diastolic left ventricular pressure t...

Losano, Giovanni Alberto; Pagliaro, Pasquale

1992-01-01

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CIRCANNUAL VARIATION IN HUMAN DIASTOLIC BLOOD PRESSURE DURING CONSECUTIVE SOLAR CYCLES  

OpenAIRE

Putative circadecadal modulations of a circannual variation in diastolic blood pressure are explored in a still accumulating 35 year record of self-measurements by a clinically healthy man. Analyses of monthly means by gliding spectra, one-way analysis of variance (ANOVA), and cosinor were carried out after removing data collected during travel across time zones or during illness. An about yearly change in diastolic blood pressure may or may not be detected with statistical significance by co...

Sothern, R. B.; Corne?lissen, G.; Katinas, G.; Mitsutake, G.; Nintcheu-fata, S.; Siegelova?, J.; Fis?er, B.; Homolka, P.; Vank, P.; Halberg, F.

2005-01-01

14

Multivariate Modeling of Body Mass Index, Pulse Pressure, Systolic and Diastolic Blood Pressure in Chinese Twins  

DEFF Research Database (Denmark)

Systolic and diastolic blood pressure, pulse pressure (PP), and body mass index (BMI) are heritable traits in human metabolic health but their common genetic and environmental backgrounds are not well investigated. The aim of this article was to explore the phenotypic and genetic associations among PP, systolic blood pressure (SBP), diastolic blood pressure (DBP), and BMI. The studied sample contained 615 twin pairs (17–84 years) collected in the Qingdao municipality. Univariate and multivariate structural equation models were fitted for assessing the genetic and environmental contributions. The AE model combining additive genetic (A) and unique environmental (E) factors produced the best fit for each four phenotypes. Heritability estimated in univariate analysis ranged from 0.42 to 0.74 with the highest for BMI (95% CI 0.70–0.78), and the lowest for PP (95% CI 0.34–0.49). The multivariate model estimated (1) high genetic correlations for DBP with SBP (0.87), PP with SBP (0.75); (2) low–moderate genetic correlations between PP and DBP (0.32), each BP component and BMI (0.24–0.37); (3) moderate unique environmental correlation for PP with SBP (0.68) and SBP with DBP (0.63); (4) there was no significant unique environmental correlation between PP and BMI. Overall, our multivariate analyses revealed common genetic and environmental backgrounds for PP, BP, and BMI in Chinese twins.

Wu, Yili; Zhang, Dongfeng

2015-01-01

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Casein improves brachial and central aortic diastolic blood pressure in overweight adolescents: a randomised, controlled trial  

DEFF Research Database (Denmark)

Arterial stiffness, blood pressure (BP) and blood lipids may be improved by milk in adults and the effects may be mediated via proteins. However, limited is known about the effects of milk proteins on central aortic BP and no studies have examined the effects in children. Therefore, the present trial examined the effect of milk and milk proteins on brachial and central aortic BP, blood lipids, inflammation and arterial stiffness in overweight adolescents. A randomised controlled trial was conducted in 193 overweight adolescents aged 12–15 years. They were randomly assigned to drink 1 litre of water, skimmed milk, whey or casein for 12 weeks. The milk-based test drinks contained 35 g protein/l. The effects were compared with the water group and a pretest control group consisting of thirty-two of the adolescents followed 12 weeks before the start of the intervention. Outcomes were brachial and central aortic BP, pulse wave velocity and augmentation index, serum C-reactive protein and blood lipids. Brachial and central aortic diastolic BP (DBP) decreased by 2·7% (P= 0·036) and 2·6% (P = 0·048), respectively, within the casein group and the changes were significantly different from those of the pretest control group (P = 0·040 and P = 0·034, respectively). There was a significant increase in central aortic DBP, and in brachial and central systolic BP in the whey group compared with the water group (P = 0·003, P= 0·009 and P = 0·002, respectively). There were no changes in measures of arterial stiffness or blood lipid concentrations. A high intake of casein improves DBP in overweight adolescents. Thus, casein may be beneficial for younger overweight subjects in terms of reducing the longterm risk of CVD. In contrast, whey protein seems to increase BP compared with drinking water; however, water may be considered an active control group.

Arnberg, Karina; Larnkjær, Anni

2013-01-01

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Estimation of left ventricular end diastolic pressure by tissue doppler imaging in patients with acute myocardial infarction  

International Nuclear Information System (INIS)

Objective: To evaluate sensitivity and specificity of E / Ea > 10 for prediction of LVEDP > 15 mmHg in patients with coronary artery disease undergoing left heart catheterization. Materials and Methods: Sixty patients of acute transmural myocardial infarction at Jinnah Hospital Lahore were enrolled in study from December 2008 to December 2009. Patients with sinus rhythm were included in the study. Patients with valvular heart disease, complete right/left bundle branch block, Pacemaker dependence, Atrial fibrillation and Post mitral valve replacement were excluded. All patients were examined by performing trans thoracic Doppler echocardiography. The trans-mitral LV filling signal was traced manually and the following variables were obtained: peak early (E) and late (A) trans-mitral velocities, and E/A ratio. Tissue - Doppler derived indices were recorded at the lateral mitral annulus. These indices included systolic velocities (S'), early diastolic (Ea) velocities and late diastolic (Aa) velocities. Finally, the dimensionless index of E/Ea was calculated. All were averaged from at least three beats. Cardiac catheterization was performed via trans-femoral / trasradial route using six French (6F) sheaths. Left ventricular diastolic pressure was directly measured by fluid filled pigtail catheter attached to a pressure transducer. Results: Mean age of the study population was 56.8 +- 12.7 years. There were 47 (78.3%) males and 13 (21.7%) females. Diabetes mellitus was pres21.7%) females. Diabetes mellitus was present in 12(20%), hypertension in 32 (53.3%), smoking in 35 (58.3%), dyslipidemia in 24 (40%). Anterior wall myocardial infarction occurred in 44 (73.3%) and inferior wall MI in 16 (26.7%). Grade I diastolic dysfunction was present in 22 (36.7%), Grade II in 31 (51.7%) and Grade III in 7 (11.7%) patients. E/E 15 in 9 (15%). Overall 21 patients were true positive, 6 were false positive, 25 were true negative and 8 were false negative. By applying 2 X 2 table sensitivity was 77.7%, specificity was 80.6%, positive predictive value was 77.7% and negative predictive value was 75.7%. Conclusion: Doppler echocardiography provided major insights into the pathophysiology of diastolic LV dysfunction. E/Ea ratio is a reasonably good index for predicting elevated left ventricular filling pressure. E/Ea significantly correlated with LVEDP in the population with high prevalence of coronary artery disease. This method is the standard in measuring pressures in most clinical settings. (author)

17

CIRCANNUAL VARIATION IN HUMAN DIASTOLIC BLOOD PRESSURE DURING CONSECUTIVE SOLAR CYCLES.  

Science.gov (United States)

Putative circadecadal modulations of a circannual variation in diastolic blood pressure are explored in a still accumulating 35 year record of self-measurements by a clinically healthy man. Analyses of monthly means by gliding spectra, one-way analysis of variance (ANOVA), and cosinor were carried out after removing data collected during travel across time zones or during illness. An about yearly change in diastolic blood pressure may or may not be detected with statistical significance by cosinor or ANOVA, apparently as a function of solar cycle number and/or stage. It appears to be, however, 1 year synchronized in the entire span analysed as a whole. A given variable such as diastolic blood pressure may be characterized by multifrequency rhythms that may intermodulate, so that findings in different stages of cycles with the lowest (e.g., circadecadal) frequency mapped may determine different outcomes in cycles with higher frequencies, such as circannuals. PMID:19424514

Sothern, R B; Cornélissen, G; Katinas, G; Mitsutake, G; Nintcheu-Fata, S; Siegelová, J; Fišer, B; Homolka, P; Vank, P; Halberg, F

2005-04-01

18

EFFECT OF GENDER DIFFERENCE AND CIRCADIAN RHYTHM ON DIASTOLIC BLOOD PRESSURE FOR VOLLEYBALL PLAYERS  

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Full Text Available The purpose of the study was to find out the effect of gender difference and circadian rhythm on diastolic blood pressure for volleyball players. METHODS: To achieve the purpose, a total of thirty volleyball players [men (n = 15 and women (n = 15] age between 19 years and 22 years from Einstein College of Engineering, Tamil Nadu, India were selected as subjects. The two independent variables of gender and circadian variations and dependent variable of diastolic blood pressure were selected for this study. The experimental design used was static group factorial design. The data were collected at 02:00, 06:00, 10:00, 14:00, 18:00 and 22:00 hours on diastolic blood pressure by using Erkameter during the academic year of 2009 – 2010. Collected data were subjected to statistical analysis by using two-way factorial (2 x 6 Analysis of Variance (ANOVA and Cosinor analysis. RESULTS: There was insignificant difference between genders, significant difference at different times of the day and insignificant circadian rhythmicity exists on diastolic blood pressure for women and significant for men. CONCLUSION: It is recommended to the physical educators to adopt the findings of this study while planning to improve sports skills for the players and athletes.

I. Rajagopal

2011-04-01

19

The influence of coronary angioplasty of the infarct-dependent artery on systolic and diastolic function of the left ventricle.  

Science.gov (United States)

The target of research is to compare the changes of systolic and diastolic functions of the left ventricle in patients with at least one month infarction after infarct-dependent artery recanalization through elective stenting. The group of 60 patients was selected, 47 men and 13 women, who underwent hospitalization in Central Hospital of Oilworkers in 2006-2007. The investigation was conducted on 30 patients (24 men and 6 women), who underwent elective stenting of LAD. The control group was composed of 30 patients (23 men and 7 women) after anterior myocardial infarction without further stenting of infarct-dependent artery. The clinical diagnosis was confirmed by coronary ventriculography. The patients underwent the echocardiography the day before stenting. The "Sonoline G60 (Siemens, Germany)" machine with 2.5MHz probe has been used. The echocardiography was repeated after 7 days and 3, 6, 12 months after stent implantation. The standard parameters of systolic and diastolic function of the left ventricle were identified during investigation. The statistical processing was delivered through PC with Excel program set. All data are presented in (M+/-m), where the M--mean value, m--standard mean fault. Comparison of the data was conducted with Student criterion. The results of treatment of patients with and without further stenting of infarct-dependent artery were compared. It was found that the stenting of infarct-dependent artery with standard therapy in patients after myocardial infarction has better impact on systolic function, than traditional medical therapy without further reperfusion. The stenting of infarct-dependent artery facilitates earlier improvement of the systolic and diastolic function of the left ventricle. The diastolic relaxation grade of the left ventricle after stenting of the left coronary artery is higher, than in patients without further revascularization. PMID:19644191

Khalilov, Sh D; Guluzade, V U; Alieva, Kh A; Mirzakhanova, L R; Imanov, G G

2009-01-01

20

Coronary Flow Reserve Predicts Cardiopulmonary Fitness in Patients with Coronary Artery Disease Independently of Systolic and Diastolic Function  

DEFF Research Database (Denmark)

Aims Despite revascularization and optimal medical treatment, patients with coronary artery disease (CAD) have reduced exercise capacity. In the absence of coronary artery stenosis, coronary flow reserve (CFR) is a measure of coronary microvascular function, and a marker of future poor outcome in CAD patients. The aim of this study was to examine the relationship among CFR, systolic and diastolic function, peripheral vascular function, and cardiopulmonary fitness in CAD patients. Methods and Results Forty patients with median left ventricular ejection fraction (LVEF) 49 (interquartile 46–55) with documented CAD without significant left anterior descending artery (LAD) stenosis underwent cardiorespiratory exercise test with measurement of VO2peak, digital measurement of endothelial function and arterial stiffness, and an echocardiography with measurement of LVEF using the biplane Simpson model, mitral early (E) and late (A) inflow velocities, and tissue Doppler diastolic (e?) and systolic (s?) velocities. Peak coronary flow velocity (CFV) was measured in the LAD using pulse-wave Doppler. CFR was calculated as the ratio between peak CFV at rest and during vasodilator stress. Median CFR was 2.22 (1.90–2.62) and VO2peak was 21.8 (17.6–25.5). VO2peak correlated significantly with CFR (r = 0.57, P < 0.001), E/e? (r = ?0.35, P = 0.04), and s? (r = 0.41, P = 0.01) and with LVEF (r = 0.35, P = 0.03). CFR remained independently associated with VO2peak after adjustment for systolic and diastolic function. Conclusions Coronary flow reserve measured noninvasively predicts cardiopulmonary fitness independently of resting systolic and diastolic function in CAD patients, indicating that cardiac output during maximal exercise is dependent on the ability of the coronary circulation to adapt to the higher metabolic demands of the myocardium.

Snoer, Martin; Olsen, Rasmus Huan

2014-01-01

21

Arterial pressure measurement: Is the envelope curve of the oscillometric method influenced by arterial stiffness?  

Energy Technology Data Exchange (ETDEWEB)

Measurement of peripheral arterial pressure using the oscillometric method is commonly used by professionals as well as by patients in their homes. This non invasive automatic method is fast, efficient and the required equipment is affordable with a low cost. The measurement method consists of obtaining parameters from a calibrated decreasing curve that is modulated by heart beats witch appear when arterial pressure reaches the cuff pressure. Diastolic, mean and systolic pressures are obtained calculating particular instants from the heart beats envelope curve. In this article we analyze the envelope of this amplified curve to find out if its morphology is related to arterial stiffness in patients. We found, in 33 volunteers, that the envelope waveform width correlates to systolic pressure (r=0.4, p<0.05), to pulse pressure (r=0.6, p<0.05) and to pulse pressure normalized to systolic pressure (r=0.6, p<0.05). We believe that the morphology of the heart beats envelope curve obtained with the oscillometric method for peripheral pressure measurement depends on arterial stiffness and can be used to enhance pressure measurements.

Gelido, G [Electronic department, Universidad Tecnologica Nacional FRBA, Bs. As. (Argentina); Angiletta, S [Electronic department, Universidad Tecnologica Nacional FRBA, Bs. As. (Argentina); Pujalte, A [Electronic department, Universidad Tecnologica Nacional FRBA, Bs. As. (Argentina); Quiroga, P [Electronic department, Universidad Favaloro FICEN, Bs. As. (Argentina); Cornes, P [Electronic department, Universidad Favaloro FICEN, Bs. As. (Argentina); Craiem, D [Electronic department, Universidad Favaloro FICEN, Bs. As. (Argentina)

2007-11-15

22

Arterial pressure measurement: Is the envelope curve of the oscillometric method influenced by arterial stiffness?  

International Nuclear Information System (INIS)

Measurement of peripheral arterial pressure using the oscillometric method is commonly used by professionals as well as by patients in their homes. This non invasive automatic method is fast, efficient and the required equipment is affordable with a low cost. The measurement method consists of obtaining parameters from a calibrated decreasing curve that is modulated by heart beats witch appear when arterial pressure reaches the cuff pressure. Diastolic, mean and systolic pressures are obtained calculating particular instants from the heart beats envelope curve. In this article we analyze the envelope of this amplified curve to find out if its morphology is related to arterial stiffness in patients. We found, in 33 volunteers, that the envelope waveform width correlates to systolic pressure (r=0.4, p<0.05), to pulse pressure (r=0.6, p<0.05) and to pulse pressure normalized to systolic pressure (r=0.6, p<0.05). We believe that the morphology of the heart beats envelope curve obtained with the oscillometric method for peripheral pressure measurement depends on arterial stiffness and can be used to enhance pressure measurements

23

Double product response and diastolic blood pressure in treadmill, stationary bicycle and muscular circuit exercises  

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Full Text Available Among the various causes for cardiovascular problems affecting the world population nowadays, the most relevant risk factors is sedentary lifestyle. Many studies have been carried out to analyse and elucidate main adaptations on the cardiovascular system stimulated by different sorts of exercises.In this way, this study had aimed at comparing the acute response of double product (DP and diastolic blood pressure (DBP after treadmill (TRM, stationary bicycle (BIC or muscle circuit training (MCT exercises. Nine individuals (6 women and 3 men exercised at 60% of heart rate reserve (HRR on the TRM and BIC and at 60% of one repetition maximum (1RM in MCT. The results showed that pre- and post-effort DP were significantly difference in all three exercises. However, DP did not differ among exercise types. The hypotensive DBP pos-effort response was greater in MCT. According to the results, it was concluded that there is no difference on the heart work demand rate estimated by DP among the three exercises and MCT at 60% 1RM provokes a greater hypotensive DBP post-effort response. . Resumo Entre as diversas causas de problemas cardiovasculares que afetam a população mundial, na atualidade, o sedentarismo é apontado como um dos fatores de risco mais relevantes. Vários estudos têm se preocupado em analisar e esclarecer as principais adaptações provocadas pelos diferentes tipos de exercícios sobre o sistema cardiovascular. Seguindo esta linha o presente trabalho teve como objetivo analisar e comparar a resposta aguda do duplo produto (DP e a pressão arterial diastólica (PAD em exercício de esteira, bicicleta estacionária e circuito na musculação. Foram avaliados nove indivíduos sendo seis mulheres e três homens, na esteira, a 60% da freqüência cardíaca de reserva (FCR, na bicicleta estacionária, a 60% FCR e circuito de musculação a 60% de 1 repetição máxima (1RM. Os resultados encontrados apresentaram diferença significativa do DP pré e pós esforço nos três exercícios. Quando comparado, o DP obtido pós esforço, nos três exercícios, não houve diferença significativa. A resposta hipotensiva da PAD pós-esforço foi mais acentuada após exercício de circuito em musculação, quando comparada com as outras modalidades exercício analisadas. De acordo com os procedimentos metodológicos adotados e os resultados obtidos, concluiu-se que não há diferença na taxa de exigência de trabalho do miocárdio entre os três exercicios analisados e que o circuito de musculação, a 60% 1RM, provoca uma maior resposta hipotensiva da PAD pós-esforço.

Leandro Teixeira Paranhos Lopes

2006-08-01

24

Resting early peak diastolic filling rate: a sensitive index of myocardial dysfunction in patients with coronary artery disease  

International Nuclear Information System (INIS)

Resting first-pass radionuclide angiocardiography (RNA) was used to derive left-ventricular (LV) peak diastolic filling rates (PFR) in normals (Group 1:N . 12) and in patients with coronary artery disease (CAD), both without (Group 2:N . 27) and with previous myocardial infarction (Group 3:N . 23). Resting peak filling rates were significantly depressed in both Group 2 (1.61 +/- 0.36; p less than 0.01) and Group 3 (1:35 +/- 0.26; p less than 0.001) patients when compared with Group 1, normals (2.14 +/- 0.63). Even though LV systolic function of Group 2 patients was normal and comparable to that in Group 1 (EF . 0.55 +/- 0.06 against EF 0.55 +/- 0.06 NS), diastolic dysfunction [PFR less than 1.61 end diastolic volume/sec (EDV/sec)] was present at rest in 14 of 27 (52%). Depressed PFR values was also seen in 20 of 23 Group 3 patients (87%). It appears that (a) resting PFR is a sensitive and easily obtainable parameter of the diastolic dysfunction associated with CAD; (b) abnormal PFR values are seen in almost all patients with previous myocardial damage, and (c) a significant proportion of CAD patients without any evidence of abnormal systolic function have depressed resting PFR of the LV

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Accuracy of mean arterial pressure and blood pressure measurements in predicting pre-eclampsia: systematic review and meta-analysis  

OpenAIRE

OBJECTIVE: To determine the accuracy of using systolic and diastolic blood pressure, mean arterial pressure, and increase of blood pressure to predict pre-eclampsia. DESIGN: Systematic review with meta-analysis of data on test accuracy. DATA SOURCES: Medline, Embase, Cochrane Library, Medion, checking reference lists of included articles and reviews, contact with authors. Review methods Without language restrictions, two reviewers independently selected the articles in which the accuracy of b...

Cnossen, J. S.; Vollebregt, K. C.; Vrieze, N.; Ter Riet, G.; Mol, B. W. J.; Franx, A.; Khan, K. S.; Vam Post, J. A. M.

2008-01-01

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Arterial blood pressure measurement and pulse wave analysis—their role in enhancing cardiovascular assessment  

International Nuclear Information System (INIS)

The most common method of clinical measurement of arterial blood pressure is by means of the cuff sphygmomanometer. This instrument has provided fundamental quantitative information on arterial pressure in individual subjects and in populations and facilitated estimation of cardiovascular risk related to levels of blood pressure obtained from the brachial cuff. Although the measurement is taken in a peripheral limb, the values are generally assumed to reflect the pressure throughout the arterial tree in large conduit arteries. Since the arterial pressure pulse becomes modified as it travels away from the heart towards the periphery, this is generally true for mean and diastolic pressure, but not for systolic pressure, and so pulse pressure. The relationship between central and peripheral pulse pressure depends on propagation characteristics of arteries. Hence, while the sphygmomanometer gives values of two single points on the pressure wave (systolic and diastolic pressure), there is additional information that can be obtained from the time-varying pulse waveform that enables an improved quantification of the systolic load on the heart and other central organs. This topical review will assess techniques of pressure measurement that relate to the use of the cuff sphygmomanometer and to the non-invasive registration and analysis of the peripheral and central arterial pressure waveform. Improved assessment of cardiovascular function in relation to treatment and management of high blood pressure will result from future developments in the indirect measurement of arterial blood pressure that involve the conventional cuff sphygmomanometer with the addition of information derived from the peripheral arterial pulse. (topical review)

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The conundrum of arterial stiffness, elevated blood pressure, and aging.  

Science.gov (United States)

Isolated systolic hypertension is a major health burden that is expanding with the aging of our population. There is evidence that central arterial stiffness contributes to the rise in systolic blood pressure (SBP); at the same time, central arterial stiffening is accelerated in patients with increased SBP. This bidirectional relationship created a controversy in the field on whether arterial stiffness leads to hypertension or vice versa. Given the profound interdependency of arterial stiffness and blood pressure, this question seems intrinsically challenging, or probably naïve. The aorta's function of dampening the pulsatile flow generated by the left ventricle is optimal within a physiological range of distending pressure that secures the required distal flow, keeps the aorta in an optimal mechanical conformation, and minimizes cardiac work. This homeostasis is disturbed by age-associated, minute alterations in aortic hemodynamic and mechanical properties that induce short- and long-term alterations in each other. Hence, it is impossible to detect an "initial insult" at an epidemiological level. Earlier manifestations of these alterations are observed in young adulthood with a sharp decline in aortic strain and distensibility accompanied by an increase in diastolic blood pressure. Subsequently, aortic mechanical reserve is exhausted, and aortic remodeling with wall stiffening and dilatation ensue. These two phenomena affect pulse pressure in opposite directions and different magnitudes. With early remodeling, there is an increase in pulse pressure, due to the dominance of arterial wall stiffness, which in turn accelerates aortic wall stiffness and dilation. With advanced remodeling, which appears to be greater in men, the effect of diameter becomes more pronounced and partially offsets the effect of wall stiffness leading to plateauing in pulse pressure in men and slower increase in pulse pressure (PP) than that of wall stiffness in women. The complex nature of the hemodynamic changes with aging makes the "one-size-fits-all" approach suboptimal and urges for therapies that address the vascular profile that underlies a given blood pressure, rather than the blood pressure values themselves. PMID:25687599

AlGhatrif, Majd; Lakatta, Edward G

2015-02-01

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Higher diastolic blood pressure at admission and antiedema therapy is associated with acute kidney injury in acute ischemic stroke patients  

Directory of Open Access Journals (Sweden)

Full Text Available Hasan Micozkadioglu Department of Nephrology, Faculty of Medicine Hospital of Adana, Baskent University School of Medicine, Adana, Turkey Abstract: Antiedema therapy with mannitol and furosemide is widely used for prevention and management of cerebral edema, elevated intracranial pressure, and cerebral hernia. There are some reports about mannitol and furosemide as risk factors of acute kidney injury (AKI. We investigated the risk factors for AKI including antiedema therapy in acute ischemic stroke patients. The subjects were 129 patients with acute ischemic stroke including 56 females and 73 males with a mean age 68.16±12.29 years. Patients were divided into two groups: patients with AKI and without AKI according to Acute Kidney Injury Network criteria. All patients had undergone cranial, carotid, and vertebral artery evaluation with magnetic resonance imaging. The number of patients with AKI was 14 (10.9%. Subjects experiencing atrial fibrillation (P=0.043 and higher diastolic blood pressure (DBP (P=0.032 treated with mannitol (P=0.019 and furosemide (P=0.019 disclosed significant association with AKI. Regression analysis revealed that higher DBP (P=0.029 and management with mannitol (P=0.044 were the risk factors for AKI. Higher DBP at admission is the most important risk factor for AKI. However antiedema therapy should be used carefully in patients with acute ischemic stroke. Serum creatinine levels or estimated glomerular filtration rate should be watched frequently to prevent AKI. Keywords: furosemide, mannitol, renal failure, cerebrovascular disease

Micozkadioglu H

2014-02-01

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Comparison of directly measured arterial blood pressure at various anatomic locations in anesthetized dogs.  

Science.gov (United States)

OBJECTIVE To determine whether directly measured arterial blood pressure differs among anatomic locations and whether arterial blood pressure is influenced by body position. ANIMALS 33 client-owned dogs undergoing anesthesia. PROCEDURES Dogs undergoing anesthetic procedures had 20-gauge catheters placed in both the superficial palmar arch and the contralateral dorsal pedal artery (group 1 [n = 20]) or the superficial palmar arch and median sacral artery (group 2 [13]). Dogs were positioned in dorsal recumbency, and mean arterial blood pressure (MAP), systolic arterial blood pressure (SAP), and diastolic arterial blood pressure (DAP) were recorded for both arteries 4 times (2-minute interval between successive measurements). Dogs were positioned in right lateral recumbency, and blood pressure measurements were repeated. RESULTS Differences were detected between pressures measured at the 2 arterial sites in both groups. This was especially true for SAP measurements in group 1, in which hind limb measurements were a mean of 16.12 mm Hg higher than carpus measurements when dogs were in dorsal recumbency and 14.70 mm Hg higher than carpus measurements when dogs were in lateral recumbency. Also, there was significant dispersion about the mean for all SAP, DAP, and MAP measurements. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that arterial blood pressures may be dependent on anatomic location and body position. Because this may affect outcomes of studies conducted to validate indirect blood pressure measurement systems, care must be used when developing future studies or interpreting previous results. PMID:25710763

Acierno, Mark J; Domingues, Michelle E; Ramos, Sara J; Shelby, Amanda M; da Cunha, Anderson F

2015-03-01

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Spectral analysis of heart rate and arterial pressure variability after nitric oxide synthase inhibition.  

Science.gov (United States)

The experiments were performed on male, conscious Wistar rats. Femoral arterial pressure was registered by Statham GOULD P23 ID pressure transducer connected to MP 100WS BIOPAC work station after analog to digital conversion during 40 minutes long control period. Nitric oxide synthase inhibition was performed by injection of 100 microliters, 10 mg/kg b.w. N-omega-nitro-L-arginine methyl ester (L-NAME) in saline through femoral vein catheter. Twenty minutes later arterial pressure registration was started and was continued for 40 minutes. The pulse-by-pulse values of systolic, diastolic and mean arterial pressure as well as the pulse intervals were measured by peak and rate detectors of the AcqKnowledge 2.0 software. Row data were processed using a virtual instrument developed in our laboratory in the graphical programming environment Lab VIEW 3.1.1. L-NAME increased systolic, diastolic and mean arterial pressure by 16.6%, 25% and 35%, respectively. The PMF/PHF ratio in heart rate spectrum decreased, indicating an increased vagal effect on the heart. Nitric oxide synthase inhibition increased the low-frequency component of systolic arterial blood pressure variability by 39.5%. Nitric oxide is a physiological regulator of rapid fluctuations of arterial blood pressure. PMID:10672333

Mikhov, D; Markova, P; Girchev, R

1998-01-01

31

Correlation of radiological assessment of congestive heart failure with left ventricular end-diastolic pressure  

International Nuclear Information System (INIS)

Left ventricular end-diastolic pressure (LVEDP) has been considered a reliable indicator of left ventricular function. The purpose of this study was to correlate the radiologic assessment of congestive heart failure with LVEDP. The population of the study consisted of 85 consecutive cases in four ranges of LVEDP (24). The PA chest radiographs obtained 1 day prior to cardiac catherization were assessed for radiological evidence of congestive heart failure and were graded from normal to abnormal (0-3). The results will be summarized in the authors' presentation. The discordance of radiological assessment of congestive heart failure in patients with elevated LVEDP will be discussed in light of recent advances in pathophysiologic understanding of left ventricular function and the impact of new classes of drugs in the management of these patients

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Determinantes clínicos de la presión de fin de diástole Clinical determining factors of the end of diastole's pressure  

Directory of Open Access Journals (Sweden)

Full Text Available Introducción: la falla cardiaca sobreviene a los pacientes con múltiples enfermedades cardiovasculares. Se encuentra con frecuencia, que algunos pacientes no empeoran su clase funcional, a pesar de reunir condiciones clínicas que suponen una severa alteración fisiopatológica. Estos hallazgos son confirmados al medir la presión de fin de diástole (PFD en el laboratorio de hemodinamia. Objetivo: determinar qué factores clínicos inciden en la PFD. Material y métodos: estudio retrospectivo, descriptivo de 200 pacientes estudiados (muestra aleatoria de 1730 pacientes durante el año 2005, con análisis de las relaciones entre la variable dependiente PFD y las variables independientes: edad, sexo, peso, superficie corporal, factores de riesgo, cuadro clínico, fracción de eyección (FE, alteraciones estructurales ventriculares (dilatación o hipertrofia, compromiso coronario (uno, dos o tres vasos, angiográficamente sanos, o presencia de flujo lento intracoronario, y la arteria coronaria comprometida. Se aplicó un modelo de regresión lineal simple mediante el paquete estadístico STATA Versión 9. Resultados: las variaciones de aumento de la PFD están relacionadas con: hipertensión arterial (HTA, dilatación ventricular izquierda, mayor compromiso coronario (tres vasos y presencia de ateromatosis significativa de las arterias descendente anterior y coronaria derecha. Las variaciones decrecientes de la PFD se presentaron ante el aumento de la FE y la presencia de arterias sanas. Conclusiones: se confirman algunos factores conocidos que inciden sobre la PFD, pero sorprende la ausencia de cambios significativos de la PFD ante cuadros clínicos más inestables y ante la presencia de hipertrofia. Este estudio provee elementos significativos para futuras investigaciones clínicas en el campo.Abstract Introduction: many cardiovascular diseases may cause heart failure, because of impairment of systolic or diastolic function, or both. It is frequently observed that regardless of physiopathological processes that were presumed to cause major symptoms, some patients have normal or quite normal functional class of dyspnea. This observation is sometimes confirmed in the cath lab, when the measured end diastolic pressure (EDP is normal. Objective: to study which clinical factors are related with changes in EDP. Methods: 200 patients were included in a sample of 1.730 patients studied in the Cath Lab during 2005. This retrospective, descriptive and analytic study seeked for association between EDP and independent variables such as: age, sex gender, weight, clinical risk factor for coronary artery disease, the clinical presentation, ejection fraction (EF measured, structural changes in left ventricle morphology (dilatation or hypertrophy, extent of coronary disease (one, two or three-vessel disease, normal coronaries, or reduced intracoronary flow, and the coronary artery involved. Statistically, a simple linear regression model was applied in the STATA 9 program. Results: increasing variability in the EDP was found to be significantly related with: hypertension, dilated left ventricle, 3-vessel disease, left coronary descendant and right coronary artery involvement. Decreasing variability of EDP presented with increasing EF and normal coronary arteries. Conclusions: some clinical factors were confirmed as related with altered EDP, but others, such as the more unstable clinical conditions and hypertrophy, surprisingly showed no significant relation with EDP variations. This investigation offers new pathways to future clinical studies in this area.

Luis Miguel Benítez

33

Determinantes clínicos de la presión de fin de diástole / Clinical determining factors of the end of diastole's pressure  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish Introducción: la falla cardiaca sobreviene a los pacientes con múltiples enfermedades cardiovasculares. Se encuentra con frecuencia, que algunos pacientes no empeoran su clase funcional, a pesar de reunir condiciones clínicas que suponen una severa alteración fisiopatológica. Estos hallazgos son con [...] firmados al medir la presión de fin de diástole (PFD) en el laboratorio de hemodinamia. Objetivo: determinar qué factores clínicos inciden en la PFD. Material y métodos: estudio retrospectivo, descriptivo de 200 pacientes estudiados (muestra aleatoria de 1730 pacientes) durante el año 2005, con análisis de las relaciones entre la variable dependiente PFD y las variables independientes: edad, sexo, peso, superficie corporal, factores de riesgo, cuadro clínico, fracción de eyección (FE), alteraciones estructurales ventriculares (dilatación o hipertrofia), compromiso coronario (uno, dos o tres vasos, angiográficamente sanos, o presencia de flujo lento intracoronario), y la arteria coronaria comprometida. Se aplicó un modelo de regresión lineal simple mediante el paquete estadístico STATA Versión 9. Resultados: las variaciones de aumento de la PFD están relacionadas con: hipertensión arterial (HTA), dilatación ventricular izquierda, mayor compromiso coronario (tres vasos) y presencia de ateromatosis significativa de las arterias descendente anterior y coronaria derecha. Las variaciones decrecientes de la PFD se presentaron ante el aumento de la FE y la presencia de arterias sanas. Conclusiones: se confirman algunos factores conocidos que inciden sobre la PFD, pero sorprende la ausencia de cambios significativos de la PFD ante cuadros clínicos más inestables y ante la presencia de hipertrofia. Este estudio provee elementos significativos para futuras investigaciones clínicas en el campo. Abstract in english Abstract Introduction: many cardiovascular diseases may cause heart failure, because of impairment of systolic or diastolic function, or both. It is frequently observed that regardless of physiopathological processes that were presumed to cause major symptoms, some patients have normal or quite norm [...] al functional class of dyspnea. This observation is sometimes confirmed in the cath lab, when the measured end diastolic pressure (EDP) is normal. Objective: to study which clinical factors are related with changes in EDP. Methods: 200 patients were included in a sample of 1.730 patients studied in the Cath Lab during 2005. This retrospective, descriptive and analytic study seeked for association between EDP and independent variables such as: age, sex gender, weight, clinical risk factor for coronary artery disease, the clinical presentation, ejection fraction (EF) measured, structural changes in left ventricle morphology (dilatation or hypertrophy), extent of coronary disease (one, two or three-vessel disease, normal coronaries, or reduced intracoronary flow), and the coronary artery involved. Statistically, a simple linear regression model was applied in the STATA 9 program. Results: increasing variability in the EDP was found to be significantly related with: hypertension, dilated left ventricle, 3-vessel disease, left coronary descendant and right coronary artery involvement. Decreasing variability of EDP presented with increasing EF and normal coronary arteries. Conclusions: some clinical factors were confirmed as related with altered EDP, but others, such as the more unstable clinical conditions and hypertrophy, surprisingly showed no significant relation with EDP variations. This investigation offers new pathways to future clinical studies in this area.

Luis Miguel, Benítez; José Vicente, Narváez.

2007-09-15

34

Positive-end Expiratory Pressure Influences Echocardiographic Measures of Diastolic Function: A Randomized, Crossover Study in Cardiac Surgery Patients  

DEFF Research Database (Denmark)

Ultrasonography of the cardiovascular system is pivotal for hemodynamic assessment. Diastolic function is evaluated with a combination of tissue Doppler (e' and a') and pulsed Doppler (E and A) measures of transmitral- and mitral valve annuli velocities. However, accurate echocardiographic evaluation in the intensive care unit or perioperative setting is contingent on relative resistance to positive pressure ventilation and changes in preload. This study aimed to evaluate the effects of positive end-expiratory pressure (PEEP) and positioning on echocardiographic measures of diastolic function.

Juhl-Olsen, Peter; Hermansen, Johan Fridolf

2013-01-01

35

Echocardiographic Measures of Diastolic Function Are Preload Dependent during Triggered Positive Pressure Ventilation: A Controlled Crossover Study in Healthy Subjects  

OpenAIRE

Background. The use of echocardiography in intensive care settings impacts decision making. A prerequisite for the use of echocardiography is relative resistance to changes in volume status and levels of positive pressure ventilation (PPV). Studies on indices of diastolic function report conflicting results with regard to dependence on volume status. Evidence is scarce on PPV. Methods. Ten healthy subjects were exposed to 6 levels of positive end-expiratory pressure (PEEP) and pressure suppor...

Peter Juhl-Olsen; Christian Alcaraz Frederiksen; Johan Fridolf Hermansen; Carl-Johan Jakobsen; Erik Sloth

2012-01-01

36

Understanding the need of ventricular pressure for the estimation of diastolic biomarkers  

OpenAIRE

The diastolic function (i.e., blood filling) of the left ventricle (LV) is determined by its capacity for relaxation, or the decay in residual active tension (AT) generated during systole, and its constitutive material properties, or myocardial stiffness. The clinical determination of these two factors (diastolic residual AT and stiffness) is thus essential for assessing LV diastolic function. To quantify these two factors, in our previous work, a novel model-based parameter estimation approa...

Xi, Jiahe; Shi, Wenzhe; Rueckert, Daniel; Razavi, Reza; Smith, Nicolas P.; Lamata, Pablo

2013-01-01

37

Post-exercise contractility, diastolic function, and pressure: Operator-independent sensor-based intelligent monitoring for heart failure telemedicine  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background New sensors for intelligent remote monitoring of the heart should be developed. Recently, a cutaneous force-frequency relation recording system has been validated based on heart sound amplitude and timing variations at increasing heart rates. Aim To assess sensor-based post-exercise contractility, diastolic function and pressure in normal and diseased hearts as a model of a wireless telemedicine system. Methods We enrolled 150 patients and 22 controls referred for exercise-stress echocardiography, age 55 ± 18 years. The sensor was attached in the precordial region by an ECG electrode. Stress and recovery contractility were derived by first heart sound amplitude vibration changes; diastolic times were acquired continuously. Systemic pressure changes were quantitatively documented by second heart sound recording. Results Interpretable sensor recordings were obtained in all patients (feasibility = 100%. Post-exercise contractility overshoot (defined as increase > 10% of recovery contractility vs exercise value was more frequent in patients than controls (27% vs 8%, p 1 in 20 patients and in none of the controls (p 1 in only 3 patients (p Conclusion Post-exercise contractility, diastolic time and pressure changes can be continuously measured by a cutaneous sensor. Heart disease affects not only exercise systolic performance, but also post-exercise recovery, diastolic time intervals and blood pressure changes – in our study, all of these were monitored by a non-invasive wearable sensor.

Giannoni Massimo

2009-05-01

38

Calpain-5 gene variants are associated with diastolic blood pressure and cholesterol levels  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Genes implicated in common complex disorders such as obesity, type 2 diabetes mellitus (T2DM or cardiovascular diseases are not disease specific, since clinically related disorders also share genetic components. Cysteine protease Calpain 10 (CAPN10 has been associated with T2DM, hypertension, hypercholesterolemia, increased body mass index (BMI and polycystic ovary syndrome (PCOS, a reproductive disorder of women in which isunlin resistance seems to play a pathogenic role. The calpain 5 gene (CAPN5 encodes a protein homologue of CAPN10. CAPN5 has been previously associated with PCOS by our group. In this new study, we have analysed the association of four CAPN5 gene variants(rs948976A>G, rs4945140G>A, rs2233546C>T and rs2233549G>A with several cardiovascular risk factors related to metabolic syndrome in general population. Methods Anthropometric measurements, blood pressure, insulin, glucose and lipid profiles were determined in 606 individuals randomly chosen from a cross-sectional population-based epidemiological survey in the province of Segovia in Central Spain (Castille, recruited to investigate the prevalence of anthropometric and physiological parameters related to obesity and other components of the metabolic syndrome. Genotypes at the four polymorphic loci in CAPN5 gene were detected by polymerase chain reaction (PCR. Results Genotype association analysis was significant for BMI (p ? 0.041, diastolic blood pressure (p = 0.015 and HDL-cholesterol levels (p = 0.025. Different CAPN5 haplotypes were also associated with diastolic blood pressure (DBP (0.0005 ? p ? 0.006 and total cholesterol levels (0.001 ? p ? 0.029. In addition, the AACA haplotype, over-represented in obese individuals, is also more frequent in individuals with metabolic syndrome defined by ATPIII criteria (p = 0.029. Conclusion As its homologue CAPN10, CAPN5 seems to influence traits related to increased risk for cardiovascular diseases. Our results also may suggest CAPN5 as a candidate gene for metabolic syndrome.

Morón Francisco J

2007-01-01

39

Alterations in Pulse Pressure Affect Artery Function  

OpenAIRE

Pulse pressure changes in response to cardiovascular diseases and interventions, but its effect on vascular wall structure and function is poorly understood. We examined the effect of increased or decreased pulse pressure on artery function, cellular function, and extracellular matrix remodeling. Porcine carotid arteries were cultured under non-pulsatile (100 mmHg), pulsatile (70-130 mmHg), or hyper-pulsatile pressure (50-150 mmHg) for 1 to 3 days. Vasomotor response, wall permeability, cell ...

Hayman, Danika M.; Xiao, Yangming; Yao, Qingping; Jiang, Zonglai; Lindsey, Merry L.; Han, Hai-chao

2012-01-01

40

Effect of magnesium deficiency on blood pressure and mechanical properties of rat carotid artery.  

Science.gov (United States)

The purpose of this study was to determine the effect of dietary Mg deficiency (80 mg/kg versus control diet: 960 mg/kg) on blood pressure and mechanical properties of the rat common carotid artery. The internal diameter and intra-arterial pressure of carotid artery were measured continuously with an echo-tracking device. At 19 weeks, systolic, diastolic, and mean blood pressures were higher in Mg-deficient rats. Histological examination showed an increase in cross-sectional area, intima-media thickness, and media-to-lumen ratio in carotid artery of Mg-deficient rats. Mg deficiency did not modify the arterial distensibility-blood pressure curve. At mean blood pressure, arterial distensibility was significantly less in 19-week-old rats than in 5-week-old rats of both control and Mg-deficient groups. A significant interaction between age and Mg-deficient diet on arterial distensibility (Pincremental elastic modulus-stress curve. In conclusion, the increased blood pressure and the vascular morphological alterations observed in Mg-deficient rats may contribute to an accelerated alteration of the wall material, which in turn leads to a stiffening of the carotid artery. PMID:10334795

Laurant, P; Hayoz, D; Brunner, H R; Berthelot, A

1999-05-01

41

Association of left ventricular diastolic dysfunction with 24-h aortic ambulatory blood pressure: the SAFAR study.  

Science.gov (United States)

Aortic blood pressure (BP) and 24-h ambulatory BP are both better associated with target organ damage than office brachial BP. However, it remains unclear whether a combination of these two techniques would be the optimal methodology to evaluate patients' BP in terms of left ventricular diastolic dysfunction (LVDD) prevention. In 230 participants, office brachial and aortic BPs were measured by a validated BP monitor and a tonometry-based device, respectively. 24-h ambulatory brachial and aortic BPs were measured by a validated ambulatory BP monitor (Mobil-O-Graph, Germany). Systematic assessment of patients' LVDD was performed. After adjustment for age, gender, hypertension and antihypertensive treatment, septum and lateral E/Ea were significantly associated with office aortic systolic BP (SBP) and pulse pressure (PP) and 24-h brachial and aortic SBP and PP (P?0.04), but not with office brachial BP (P?0.09). Similarly, 1 standard deviation in SBP was significantly associated with 97.8±20.9, 86.4±22.9, 74.1±23.3 and 51.3±22.6 in septum E/Ea and 68.6±20.1, 54.2±21.9, 37.9±22.4 and 23.1±21.4 in lateral E/Ea, for office and 24-h aortic and brachial SBP, respectively. In qualitative analysis, except for office brachial BP, office aortic and 24-h brachial and aortic BPs were all significantly associated with LVDD (P?0.03), with the highest odds ratio in 24-h aortic SBP. Furthermore, aortic BP, no matter in the office or 24-h ambulatory setting, showed the largest area under receiver operating characteristic curves (P?0.02). In conclusion, 24-h aortic BP is superior to other BPs in the association with LVDD.Journal of Human Hypertension advance online publication, 13 November 2014; doi:10.1038/jhh.2014.101. PMID:25391758

Zhang, Y; Kollias, G; Argyris, A A; Papaioannou, T G; Tountas, C; Konstantonis, G D; Achimastos, A; Blacher, J; Safar, M E; Sfikakis, P P; Protogerou, A D

2014-11-13

42

Prognostic Significance of Home Arterial Stiffness Index Derived From Self-Measurement of Blood Pressure: The Ohasama Study  

OpenAIRE

BackgroundArterial stiffness is a stroke risk factor. The home arterial stiffness index (HASI) can be calculated from self-measured blood pressure using the same formula as the calculation of ambulatory arterial stiffness index (AASI).MethodsIn 2,377 inhabitants (baseline age, 35-96 years) without a history of stroke, home blood pressure was measured once every morning for 26 days (median). HASI was defined as 1 minus the regression slope of diastolic over systolic on home blood pressure in i...

Kikuya, Masahiro; Ohkubo, Takayoshi; Satoh, Michihiro; Hashimoto, Takanao; Hirose, Takuo; Metoki, Hirohito; Obara, Taku; Inoue, Ryusuke; Asayama, Kei; Hoshi, Haruhisa; Totsune, Kazuhito; Satoh, Hiroshi; Staessen, Jan A.; Imai, Yutaka

2012-01-01

43

Relação entre gordura corporal e pressão arterial sistólica e diastólica em escolares entre 14 e 17 anos de Floriano-Piauí-Brasil / Relationship between body fat and systolic and diastolic blood pressure in students between 14 and 17 years of age in Floriano-Piauí-Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese As doenças cardiovasculares estão associadas ao estilo de vida. Com isso, este estudo tem como objetivo descrever e analisar a associação entre gordura corporal e pressão arterial sistólica entre escolares da cidade de Floriano-PI. Caracteriza-se como um estudo observacional de prevalência do tipo d [...] escritivo com delineamento de corte transversal. A população de estudo incluiu escolares com idade entre 14 e 17 anos, de ambos os sexos. Realizou-se análise descritiva de tendência central e dispersão, análise univariada e bivariada (com nível de significância de p?0,05). O índice de confiança considerado foi de 95%. Os principais resultados demonstram altas taxas de gordura corporal (51,1%) e de hipertensão arterial (18%) para os escolares, além de associação positiva significativa entre pressão arterial sistólica e gordura corporal entre os escolares do sexo feminino. Conclui-se que os escolares de Floriano apresentam fatores de riscos para o desenvolvimento de doenças crônicas não transmissíveis. Abstract in english Cardiovascular diseases are associated with lifestyle. Thus, this study aimed to describe and analyze the association between body fat and systolic blood pressure among schoolchildren in the city of Floriano-PI. It can be characterized as an observational study of prevalence with a descriptive, cros [...] s-sectional design. The study population included adolescents aged between 14 and 17 years, of both sexes. We conducted a descriptive analysis of central tendency and dispersion, with one- and two-way analysis (significance level p

Irineu de, Sousa Júnior; Márcia Cristiane, Araújo; Nanci Maria de, França.

2013-09-01

44

Effects of music on systolic blood pressure, diastolic blood pressure, and heart rate: a meta-analysis.  

Science.gov (United States)

There are a handful of studies that have been done investigating the effect of music on various vital signs, namely systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR). Many studies have also assessed effects of music on self-reported anxiety level, attributing some degree of music-induced anxiety relief to the beneficial impacts of music on vital signs. Several randomised studies have shown varying effects of music on these vital parameters and so a meta-analysis was done to compare the effect of music on them. The fixed effects model was used as studies were homogenous. A two-sided alpha error < 0.05 was considered to be statistically significant. Compared to those who did not receive music therapy, those who did receive music therapy had a significantly greater decrease in SBP before and after (difference in means, -2.629, confidence interval (CI), -3.914 to -1.344, P < 0.001), a significantly greater decrease in DBP (difference in means, -1.112, CI, -1.692 to -0.532, P < 0.001), and a significantly greater decrease in HR (difference in means, -3.422, CI, -5.032 to -1.812, P < 0.001). PMID:22664817

Loomba, Rohit S; Arora, Rohit; Shah, Parinda H; Chandrasekar, Suraj; Molnar, Janos

2012-01-01

45

High intensity interior aircraft noise increases the risk of high diastolic blood pressure in Indonesian Air Force pilots  

OpenAIRE

Aim: To analyze the effects of aircraft noise, resting pulse rate, and other factors on the risk of high diastolic blood pressure (DBP) in Indonesian Air Force pilots.Methods: A nested case-control study was conducted using data extracted from annual medical check-ups indoctrination aerophysiologic training records at the Saryanto Aviation and Aerospace Health Institute (LAKESPRA) in Jakarta from January 2003 – September 2008. For analysis of DBP: the case group with DBP ? 90 mmHg were co...

Minarma Siagian; Bastaman Basuki; Dede Kusmana

2009-01-01

46

La hipertensión arterial en la tercera edad High blood pressure in third age  

Directory of Open Access Journals (Sweden)

Full Text Available A partir de la quinta o sexta décadas de la vida, la hipertensión arterial adopta formas y obedece a causas diferentes a las del niño o a las del adulto joven. En este caso, la presión arterial sistólica aumenta (> 140 mmHg y la diastólica se mantiene o disminuye (From the fifth or sixth decades of life, high blood pressure adopts ways and is due to different causes to that of child or to that of young adult. In this case, systolic arterial pressure increases (> 140 mmHg, and the diastolic one remains or decreases (< 90 mmHg, and differential pressure increases. The cause is conduction artery stiffness by atherosclerosis as well as the action of some hormones including: adrenaline, noradrenaline, agiotensin II, and aldosterone on the arterial medium wall. Diagnosis is made verifying presence of an isolated systolic high blood pressure in patients aged over 50. In youngest, in addition to high systolic pressure with a normal or low diastolic pressure, it is advisable measurement of others indicators of aortic stiffness. Systolic pressure in third age may to be associated with: left ventricular and arterial hypertrophy, a relaxation decrease of cardiac and coronary walls, myocardial ischemia, nephroesclerosis, cognitive decline or even dementia. Treatment requires special cares and must to adjust to the frequent morbidity of old age. The more effective antihypertensive groups according to randomized assays include: agiotensin-converting enzyme (ACE inhibitors, agiotensin II blockers, aldosterone antagonists, and calcium blockers. Nitrates and diuretic agents have been used to reduce systolic pressure, especially when there is an aortic valvular regurgitation. Decrease of systolic pressure to result in a delay or an arrest of cardiovascular complications, of cognitive decline, and dementia in third age patients.

David García Barreto

2009-06-01

47

Investigation Of Arterial Blood Pressure Level And Metabolic Indices In Patients With Arterial Hypertension At Pharmacotherapy With Antihypertensive Medicines Of Various Chemical Structure  

Directory of Open Access Journals (Sweden)

Full Text Available The research goal is to carry on the comparative analysis of medicines of various chemical structure, Telmisar-tan and Bisoprolol, and to reveal their effect on the arterial blood pressure level and the indices of various metabolic processes in patients with arterial hypertension. 60 out-patients with arterial hypertension (stage II risk III both males and females aged 33-55 have been under study taking Telmisartan and Bisoprolol for 3 months. While treating the patients the arterial blood pressure level control and biochemical investigations for determination the indices of metabolic processes have been carried out. The investigated medications have provided the decrease of systolic and diastolic arterial pressure parameters, the increase of concentration of total and ionized calcium, chlorine ions, urea and total bilirubin in blood plasma. Therapy with Telmisartan has shown more significant increase of potassium level in erythro-cytes, decrease of levels of natrium, glucose, glycolized hemoglobin and triglycerides and increased contents of alani-naminotransferase and aspartataminotransferase. The course of therapy with Bisoprolol has restored the normal level of magnesium in blood plasma, has not have any influence on carbohydrate and lipid metabolism, increased the level of alaninaminotransferase and significantly increased the contents of total and ionized calcium, urea and creatinine. 3-months therapy with Telmisartan and Bisoprolol has proved the decrease of systolic and diastolic arterial pressure in patients with arterial hypertension. The medications under study have had active and variable effects on metabolic indices

G.Kh. Glybochko

2009-12-01

48

Echocardiographic Measures of Diastolic Function Are Preload Dependent during Triggered Positive Pressure Ventilation : A Controlled Crossover Study in Healthy Subjects  

DEFF Research Database (Denmark)

Background. The use of echocardiography in intensive care settings impacts decision making. A prerequisite for the use of echocardiography is relative resistance to changes in volume status and levels of positive pressure ventilation (PPV). Studies on indices of diastolic function report conflicting results with regard to dependence on volume status. Evidence is scarce on PPV. Methods. Ten healthy subjects were exposed to 6 levels of positive end-expiratory pressure (PEEP) and pressure support (PS) following a baseline reading. All ventilator settings were performed at three positions: horizontal, reverse-Trendelenburg, and Trendelenburg. Echocardiography was performed throughout. Results. During spontaneous breathing, early diastolic transmitral velocity (E) changed with positioning (P <0.001), whereas early diastolic velocity of the mitral annulus (e') was independent (P = 0.263). With PPV, E and e' proved preload dependent (P ??values <0.001). Increases in PEEP, PS, or a combination influenced E and e' in reverse-Trendelenburg- and horizontal positions, but not in the Trendelenburg position. Discussion. The change towards preload dependency of e' with PPV suggests that PPV increases myocardial preload sensitivity. The susceptibility of E and e' to preload changes during PPV discourages their use in settings of volume shifts or during changes in ventilator settings. Conclusion. Positioning and PPV affect E and e'.

Juhl-Olsen, Peter; Frederiksen, Christian Alcaraz

2012-01-01

49

Effects of verapamil and propranolol on left ventricular systolic function and diastolic filling in patients with coronary artery disease: radionuclide angiographic studies at rest and during exercise  

International Nuclear Information System (INIS)

To determine the effects of verapamil on left ventricular (LV) systolic function and diastolic filling in patients with coronary artery disease (CAD), researchers performed gated radionuclide angiography at rest and during exercise in 16 symptomatic patients before and during oral verapamil therapy (480 mg/day). Twelve patients were also studied during oral propranolol. LV ejection fraction at rest was normal in 13 patients, but abnormal diastolic filling at rest, defined as peak filling rate (PFR) less than 2.5 end-diastolic volumes (EDV)/sec or time to PFR greater than 180 msec, was present in 15. During verapamil, resting ejection fraction decreased, but resting diastolic filling improved: PFR increased and time to PFR decreased. Exercise ejection fraction did not change during verapamil, but exercise PFR increased, and exercise time to PFR decreased. In contrast, propranolol did not alter ejection fraction, PFR, or time to PFR at rest or during exercise. Thus, LV ejection fraction is decreased by verapamil at rest but is unchanged during exercise. While LV systolic function is not improved by verapamil, LV diastolic filling is enhanced by verapamil, both at rest and during exercise. These mechanisms may account in part for the symptomatic improvement in many patients during verapamil therapy

50

Measurement of Blood Pressure Using an Arterial Pulsimeter Equipped with a Hall Device  

Directory of Open Access Journals (Sweden)

Full Text Available To measure precise blood pressure (BP and pulse rate without using a cuff, we have developed an arterial pulsimeter consisting of a small, portable apparatus incorporating a Hall device. Regression analysis of the pulse wave measured during testing of the arterial pulsimeter was conducted using two equations of the BP algorithm. The estimated values of BP obtained by the cuffless arterial pulsimeter over 5 s were compared with values obtained using electronic or liquid mercury BP meters. The standard deviation between the estimated values and the measured values for systolic and diastolic BP were 8.3 and 4.9, respectively, which are close to the range of values of the BP International Standard. Detailed analysis of the pulse wave measured by the cuffless radial artery pulsimeter by detecting changes in the magnetic field can be used to develop a new diagnostic algorithm for BP, which can be applied to new medical apparatus such as the radial artery pulsimeter.

Jong-Gu Choi

2011-01-01

51

ORIGINAL PAPER
The effect of hormone replacement therapy on the left ventricle systolic and diastolic function in postmenopausal women with coronary artery disease
 

OpenAIRE

Introduction: The aim of this study was to evaluate the effect of hormone replacement therapy (HRT) on the left ventricle systolic and diastolic function. Materials and methods: Fifty-six postmenopausal women with proven coronary artery disease (CAD) were enrolled into the study (31 were assigned to HRT and 25 were matched as a control group). Clinically both groups were comparable. All patients had standard 2D and Doppler echocardiography study at the baseline and after 12 months of follow u...

Piotr Br?borowicz; Tatiana Mularek-Kubzdela; Zofia Oko-Sarnowska; Olga Trojnarska; Marzena Maciejewska; El?bieta Br?borowicz; Alina Warenik-Szymankiewicz; Andrzej Cie?li?ski

2005-01-01

52

Validation of optoelectronic monitoring system for ear arterial pressure waveforms in practical use  

Science.gov (United States)

A newly developed optoelectronic monitoring systems for ear arterial pressure waveform (Earpres) was tested in ergonomics and sports science. Changes in systolic and diastolic blood pressures and heart rate were continuously measured by the system during VDT operations such as word processing and computer games, and during two different styles of weight lifting, one-hand and two-hands curls, with three different weights respectively. Statistical analysis of the results showed that systolic and diastolic blood pressures and heart rate increased during VDT operation, and in the extreme case the increments of those were as high as 78 mmHg and 50mmHg respectively during computer game operation and 50 bpm during word processor operation. It was also statistically clarified that systolic and diastolic blood pressures and heart rate increased in accordance with weight during one-hand and two-hands curls. It was ascertained that the results obtained by Earpres agreed for the most part with physiological knowledge; some results might be new findings. Earpres was thus validated as a physiologically and ergonomically useful apparatus. Additionally, an apparatus was constructed to detect the exact location of an artery in the ear, composed of a halogen lamp, a band-pass filter, a bundle of optical fibers, and a CCD device. With the apparatus, Earpres became much easier to handle.

Imachi, Yu; Sasayama, Satoshi; Yagi, Tamotsu; Imachi, Kou; Ono, Toshirou; Man-i, Masando

1994-02-01

53

Isometric handgrip training reduces arterial pressure at rest without changes in sympathetic nerve activity  

Science.gov (United States)

The purpose of this study was to determine whether isometric handgrip (IHG) training reduces arterial pressure and whether reductions in muscle sympathetic nerve activity (MSNA) mediate this drop in arterial pressure. Normotensive subjects were assigned to training (n = 9), sham training (n = 7), or control (n = 8) groups. The training protocol consisted of four 3-min bouts of IHG exercise at 30% of maximal voluntary contraction (MVC) separated by 5-min rest periods. Training was performed four times per week for 5 wk. Subjects' resting arterial pressure and heart rate were measured three times on 3 consecutive days before and after training, with resting MSNA (peroneal nerve) recorded on the third day. Additionally, subjects performed IHG exercise at 30% of MVC to fatigue followed by muscle ischemia. In the trained group, resting diastolic (67 +/- 1 to 62 +/- 1 mmHg) and mean arterial pressure (86 +/- 1 to 82 +/- 1 mmHg) significantly decreased, whereas systolic arterial pressure (116 +/- 3 to 113 +/- 2 mmHg), heart rate (67 +/- 4 to 66 +/- 4 beats/min), and MSNA (14 +/- 2 to 15 +/- 2 bursts/min) did not significantly change following training. MSNA and cardiovascular responses to exercise and postexercise muscle ischemia were unchanged by training. There were no significant changes in any variables for the sham training and control groups. The results indicate that IHG training is an effective nonpharmacological intervention in lowering arterial pressure.

Ray, C. A.; Carrasco, D. I.

2000-01-01

54

Soybean oil increases SERCA2a expression and left ventricular contractility in rats without change in arterial blood pressure  

OpenAIRE

Abstract Background Our aim was to evaluate the effects of soybean oil treatment for 15 days on arterial and ventricular pressure, myocardial mechanics and proteins involved in calcium handling. Methods Wistar rats were divided in two groups receiving 100 ?L of soybean oil (SB) or saline (CT) i.m. for 15 days. Ventricular performance was analyzed in male 12-weeks old Wistar rats by measuring left ventricle diastolic and systolic pressure in isolated perfused hearts according to the Langendor...

Vassallo Dalton; Magalhães Siman Fabiana; Batista Priscila; Meira Eduardo; Fernandes Aurélia; Ribeiro Rogério; Padilha Alessandra; Stefanon Ivanita

2010-01-01

55

Rarefaction and blood pressure in systemic and pulmonary arteries  

OpenAIRE

The effects of vascular rarefaction (the loss of small arteries) on the circulation of blood are studied using a multiscale mathematical model that can predict blood flow and pressure in the systemic and pulmonary arteries. We augmented a model originally developed for the systemic arteries (Olufsen et al. 1998, 1999, 2000, 2004) to (a) predict flow and pressure in the pulmonary arteries, and (b) predict pressure propagation along the small arteries in the vascular beds. The systemic and pulm...

Olufsen, Mette S.; Hill, N. A.; Vaughan, Gareth D. A.; Sainsbury, Christopher; Johnson, Martin

2012-01-01

56

Effects of pressure gradients between branches of the left coronary artery on the pressure axis intercept and the shape of steady state circumflex pressure-flow relations in dogs  

International Nuclear Information System (INIS)

When steady state pressure-flow relations are studied in the circumflex coronary artery, pressure gradients develop between it and other branches of the left coronary artery. To assess the effects of these pressure gradients, the pressure axis intercept and shape of steady state circumflex pressure-flow relations were compared in the presence and absence of gradients after autoregulation was abolished, both in the beating heart and during long diastoles in dogs. The authors used peripheral coronary pressures and radionuclide-labeled microspheres to assess arterial collateral flow. In the beating heart, interarterial pressure gradients reduced the curvature at low circumflex pressures, and overestimated the mean pressure axis intercept by 7.8 mm Hg (P less than 0.05). The results were similar for the pressure-flow relations derived during long diastoles. This overestimation exaggerates the difference between the pressure axis intercept and coronary sinus pressure. The peripheral coronary pressure and microsphere results indicate that these effects are mediated largely by arterial collateral flow

57

Pressão arterial em adolescentes durante teste ergométrico / Arterial blood pressure in adolescents during exercise stress testing  

Scientific Electronic Library Online (English)

Full Text Available OBJETIVO: Descrever a resposta da pressão arterial em adolescentes submetidos ao teste de esforço. MÉTODOS: Foi realizado estudo transversal de 218 adolescentes entre 10 e 19 anos (131 do sexo masculino) submetidos a teste ergométrico, e descrita a freqüência cardíaca máxima, tempo de exercício, con [...] sumo máximo de oxigênio, pressão arterial sistólica (PAS) e diastólica (PAD) de repouso, no esforço máximo e aos seis minutos da recuperação. RESULTADOS: No repouso, a PAS teve valores maiores no sexo masculino e a PAD não mostrou diferença entre os sexos, porém ambas aumentaram com a idade. No exercício ocorreu elevação da PAS e queda da PAD em ambos os sexos. A variação da PAS foi maior no sexo masculino, principalmente acima dos 14 anos. CONCLUSÃO: A análise dos resultados demonstrou que a PAS durante o exercício teve relação direta com idade, peso, altura e índice de massa corpórea do indivíduo e a PAD teve relação apenas com a idade. Abstract in english OBJECTIVE: Describe arterial blood pressure response in adolescents undergoing exercise stress testing. METHODS: This was a cross-sectional study conducted with 218 adolescents (131 of whom were males), aged between 10 to 19 years, undergoing exercise stress testing. Maximum heart rate, total exerci [...] se time, maximum oxygen uptake, systolic blood pressure (SBP) and diastolic (DBP) at rest, during maximal physical exertion and at six minutes of recovery were measured. RESULTS: At rest, SBP values were greater in males and no difference was found in DBP between genders, although both increased with age. During exercise, SBP rose and DBP fell in both genders. SBP variation was greater in men, particularly in those over 14 years of age. CONCLUSION: Analysis of results showed that during physical exercise, SBP had a direct relationship with the individual’s age, weight, height and body mass index, whereas DBP bore a relationship to age only.

Mônica de Moraes Chaves, Becker; Odwaldo Barbosa e, Silva; Isaura Elaine Gonçalves, Moreira; Edgar Guimarães, Victor.

2007-03-01

58

Effects of verapamil and propranolol on left ventricular systolic function and diastolic filling in patients with coronary artery disease: radionuclide angiographic studies at rest and during exercise  

International Nuclear Information System (INIS)

To determine the effects of verapamil on left ventricular (LV) systolic function and diastolic filling in patients with coronary artery disease (CAD), we performed gated radionuclide angiography at rest and during exercise in 16 symptomatic patients before and during oral verapamil therapy (480 mg/day). Twelve patients were also studied during oral propranolol (160-320 mg/day). LV ejection fraction at rest was normal in 13 patients, but abnormal diastolic filling at rest, defined as peak filling rate (PFR) 180 msec, was present in 15. During verapamil, resting ejection fraction decreased (control 50 + 10% [ + SD ], verapamil 45 + 12%, p < 0.005), but resting diastolic filling improved: PFR increased (control 1.9 + 0.6 EDV/sec, verapamil 2.3 + 0.9 EDV/sec, p < 0.005) and time to PFR decreased (control 185 + 38 mssec, verapamil 161 + 27 msec, p < 0.05). Exercise ejection fraction did not change during verapamil (control 42 + 13%, verapamil 43 + 12%. NS), but exercise PFR increased (control 3.1 + 0.9 EDV/sec, verapamil 3.6 + 1.1 EDV/sec, p < 0.05) and exercise time to PFR decreased (control 108 + 30 msec, verapamil 91 + 17 msec, p < 0.05). In contrast, propranolol did not alter ejection fraction, PFR, or time to PFR at rest or during exercise. Thus, LV ejection fraction is decreased by verapamil at rest but is unchanged during exercise. While LV systolic function is not improved by verapamil, LV diastolic filling is ved by verapamil, LV diastolic filling is enhanced by verapamil, both at rest and during exercise. These mechanisms may account in part for the symptomatic improvement in many patients during verapamil therapy

59

Heart and Artery Damage and High Blood Pressure  

Science.gov (United States)

Heart and Artery Damage and High Blood Pressure Updated:Sep 11,2014 There are several harmful consequences for your arteries and heart because high blood pressure, also called HBP or hypertension, ...

60

A 3-month oral vitamin D supplementation marginally improves diastolic blood pressure in Saudi patients with type 2 diabetes mellitus.  

Science.gov (United States)

The aim of the current study was to determine whether oral cholecalciferol (45000 IU) per week for the 2 months and once on the 3rd month could translate to full vitamin D status correction and improved metabolic profile among patients with suboptimal vitamin D status. A total of 248 Saudi patients with T2DM were screened for vitamin D deficiency. Two hundred out of the 248 patients had suboptimal vitamin D levels, and were randomly assigned to receive vitamin D oral supplementation (45000 IU/week for 2 months and a single 45000 IU in the last month) or placebo for 3 months. Anthropometrics and fasting blood samples were taken at baseline and after 3 months. Serum glucose, HBA1c and lipid profile were measured routinely and serum 25-OH vitamin D using ELISA. More than half of the subjects (59.8%) were vitamin D deficient at screening. Both groups had significant improvements in vitamin D levels after 3 months, with most of the treatment group achieving status correction. In the treatment group, a significant improvement in the diastolic blood pressure was observed after 3 months (P = 0.021), while the rest of the variables were comparable. Vitamin D supplementation of 45000 IU/week for 2 months and once on the 3rd month was able to improve vitamin D status among vitamin D deficient T2DM patients and marginally improve diastolic blood pressure. PMID:25664051

Al-Zahrani, Mansour K; Elnasieh, Abdulrahman M; Alenezi, Farhan M; Almoushawah, Abdulrahman A; Almansour, Mohammed; Alshahrani, Fahad; Rahman, Saeed Ur; Al-Zahrani, Abdullah

2014-01-01

61

Age, arterial stiffness, and components of blood pressure in Chinese adults.  

Science.gov (United States)

Blood pressure (BP) changes with age. We conducted a cross-sectional study in rural Chinese adults to investigate: (1) what is the relationship between age, arterial stiffness, and BP in Chinese men and women; and (2) to what degree can the age-BP relationship be explained by arterial stiffness, controlling for other covariables. These analyses included a total of 1688 subjects (males/females: 623/1065), aged 40 to 88 years. Among them, 353 (20.9%) had hypertension (defined as systolic blood pressure (SBP) ? 140 mm Hg or diastolic blood pressure (DBP) ? 90 mm Hg). Arterial stiffness was measured by brachial-ankle pulse wave velocity (baPWV). baPWV appeared to be more strongly correlated with BP (including SBP, DBP, mean arterial pressure [MAP], pulse pressure [PP]) than age (P < 0.001 for comparisons between Spearman correlation coefficients). Furthermore, baPWV was associated with BP (including SBP, DBP, MAP, and PP) and risk of hypertension in a dose-response fashion, independent of age; in contrast, the age-BP associations were either attenuated or became negative after adjusting for baPWV. Arterial stiffness appears to be an independent contributor to hypertension, even after adjusting for age and other covariables. In contrast, age-BP associations became attenuated or negative after adjusting for baPWV. The utility of baPWV as a diagnostic, prognostic, and therapeutic indicator for hypertension warrants further investigation. PMID:25546666

Zheng, Meili; Xu, Xiping; Wang, Xiaobin; Huo, Yong; Xu, Xin; Qin, Xianhui; Tang, Genfu; Xing, Houxun; Fan, Fangfang; Cui, Wei; Yang, Xinchun

2014-12-01

62

New Cardiovascular Indices Based on a Nonlinear Spectral Analysis of Arterial Blood Pressure Waveforms  

CERN Document Server

A new method for analyzing arterial blood pressure is presented in this report. The technique is based on the scattering transform and consists in solving the spectral problem associated to a one-dimensional Schr\\"odinger operator with a potential depending linearly upon the pressure. This potential is then expressed with the discrete spectrum which includes negative eigenvalues and corresponds to the interacting components of an N-soliton. The approach is similar to a nonlinear Fourier transform where the solitons play the role of sine and cosine components. The method provides new cardiovascular indices that seem to contain relevant physiological information. We first show how to use this approach to decompose the arterial blood pressure pulse into elementary waves and to reconstruct it or to separate its systolic and diastolic phases. Then we analyse the parameters computed from this technique in two physiological conditions, the head-up 60 degrees tilt test and the isometric handgrip test, widely used for...

Laleg, Taous-Meriem; Papelier, Yves; Crépeau, Emmanuelle; Sorine, Michel

2007-01-01

63

Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure  

Science.gov (United States)

Numerous genetic loci influence systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans 1-3. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N=74,064) and follow-up studies (N=48,607), we identified at genome-wide significance (P= 2.7×10-8 to P=2.3×10-13) four novel PP loci (at 4q12 near CHIC2/PDGFRAI, 7q22.3 near PIK3CG, 8q24.12 in NOV, 11q24.3 near ADAMTS-8), two novel MAP loci (3p21.31 in MAP4, 10q25.3 near ADRB1) and one locus associated with both traits (2q24.3 near FIGN) which has recently been associated with SBP in east Asians. For three of the novel PP signals, the estimated effect for SBP was opposite to that for DBP, in contrast to the majority of common SBP- and DBP-associated variants which show concordant effects on both traits. These findings indicate novel genetic mechanisms underlying blood pressure variation, including pathways that may differentially influence SBP and DBP. PMID:21909110

Wain, Louise V; Verwoert, Germaine C; O’Reilly, Paul F; Shi, Gang; Johnson, Toby; Johnson, Andrew D; Bochud, Murielle; Rice, Kenneth M; Henneman, Peter; Smith, Albert V; Ehret, Georg B; Amin, Najaf; Larson, Martin G; Mooser, Vincent; Hadley, David; Dörr, Marcus; Bis, Joshua C; Aspelund, Thor; Esko, Tõnu; Janssens, A Cecile JW; Zhao, Jing Hua; Heath, Simon; Laan, Maris; Fu, Jingyuan; Pistis, Giorgio; Luan, Jian’an; Arora, Pankaj; Lucas, Gavin; Pirastu, Nicola; Pichler, Irene; Jackson, Anne U; Webster, Rebecca J; Zhang, Feng; Peden, John F; Schmidt, Helena; Tanaka, Toshiko; Campbell, Harry; Igl, Wilmar; Milaneschi, Yuri; Hotteng, Jouke-Jan; Vitart, Veronique; Chasman, Daniel I; Trompet, Stella; Bragg-Gresham, Jennifer L; Alizadeh, Behrooz Z; Chambers, John C; Guo, Xiuqing; Lehtimäki, Terho; Kühnel, Brigitte; Lopez, Lorna M; Polašek, Ozren; Boban, Mladen; Nelson, Christopher P; Morrison, Alanna C; Pihur, Vasyl; Ganesh, Santhi K; Hofman, Albert; Kundu, Suman; Mattace-Raso, Francesco US; Rivadeneira, Fernando; Sijbrands, Eric JG; Uitterlinden, Andre G; Hwang, Shih-Jen; Vasan, Ramachandran S; Wang, Thomas J; Bergmann, Sven; Vollenweider, Peter; Waeber, Gérard; Laitinen, Jaana; Pouta, Anneli; Zitting, Paavo; McArdle, Wendy L; Kroemer, Heyo K; Völker, Uwe; Völzke, Henry; Glazer, Nicole L; Taylor, Kent D; Harris, Tamara B; Alavere, Helene; Haller, Toomas; Keis, Aime; Tammesoo, Mari-Liis; Aulchenko, Yurii; Barroso, Inês; Khaw, Kay-Tee; Galan, Pilar; Hercberg, Serge; Lathrop, Mark; Eyheramendy, Susana; Org, Elin; Sõber, Siim; Lu, Xiaowen; Nolte, Ilja M; Penninx, Brenda W; Corre, Tanguy; Masciullo, Corrado; Sala, Cinzia; Groop, Leif; Voight, Benjamin F; Melander, Olle; O’Donnell, Christopher J; Salomaa, Veikko; d’Adamo, Adamo Pio; Fabretto, Antonella; Faletra, Flavio; Ulivi, Sheila; Del Greco, M Fabiola; Facheris, Maurizio; Collins, Francis S; Bergman, Richard N; Beilby, John P; Hung, Joseph; Musk, A William; Mangino, Massimo; Shin, So-Youn; Soranzo, Nicole; Watkins, Hugh; Goel, Anuj; Hamsten, Anders; Gider, Pierre; Loitfelder, Marisa; Zeginigg, Marion; Hernandez, Dena; Najjar, Samer S; Navarro, Pau; Wild, Sarah H; Corsi, Anna Maria; Singleton, Andrew; de Geus, Eco JC; Willemsen, Gonneke; Parker, Alex N; Rose, Lynda M; Buckley, Brendan; Stott, David; Orru, Marco; Uda, Manuela; van der Klauw, Melanie M; Zhang, Weihua; Li, Xinzhong; Scott, James; Chen, Yii-Der Ida; Burke, Gregory L; Kähönen, Mika; Viikari, Jorma; Döring, Angela; Meitinger, Thomas; Davies, Gail; Starr, John M; Emilsson, Valur; Plump, Andrew; Lindeman, Jan H; ’t Hoen, Peter AC; König, Inke R; Felix, Janine F; Clarke, Robert; Hopewell, Jemma C; Ongen, Halit; Breteler, Monique; Debette, Stéphanie; DeStefano, Anita L; Fornage, Myriam; Mitchell, Gary F; Smith, Nicholas L; Holm, Hilma; Stefansson, Kari; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Samani, Nilesh J; Preuss, Michael; Rudan, Igor; Hayward, Caroline; Deary, Ian J; Wichmann, H-Erich; Raitakari, Olli T; Palmas, Walter; Kooner, Jaspal S; Stolk, Ronald P; Jukema, J Wouter; Wright, Alan F; Boomsma, Dorret I; Bandinelli, Stefania; Gyllensten, Ulf B; Wilson, James F; Ferrucci, Luigi; Schmidt, Reinhold; Farrall, Martin; Spector, Tim D; Palmer, Lyle J; Tuomilehto, Jaakko; Pfeufer, Arne; Gasparini, Paolo; Siscovick, David; Altshuler, David; Loos, Ruth JF; Toniolo, Daniela; Snieder, Harold; Gieger, Christian; Meneton, Pierre; Wareham, Nicholas J; Oostra, Ben A; Metspalu, Andres; Launer, Lenore; Rettig, Rainer; Strachan, David P; Beckmann, Jacques S; Witteman, Jacqueline CM; Erdmann, Jeanette; van Dijk, Ko Willems; Boerwinkle, Eric; Boehnke, Michael; Ridker, Paul M; Jarvelin, Marjo-Riitta; Chakravarti, Aravinda; Abecasis, Goncalo R; Gudnason, Vilmundur; Newton-Cheh, Christopher; Levy, Daniel; Munroe, Patricia B; Psaty, Bruce M; Caulfield, Mark J; Rao, Dabeeru C

2012-01-01

64

A novel transmission-based test of association for multivariate phenotypes: an application to systolic and diastolic blood pressure levels.  

Science.gov (United States)

Unlike case-control studies, family-based tests for association are protected against population stratification. Complex genetic traits are often governed by quantitative precursors and it has been argued that it may be a more powerful strategy to analyze these quantitative precursors instead of the clinical end point trait. Although methods have been developed for family-based association tests for single quantitative traits, it is of interest to develop such methods for multivariate phenotypes. We propose a novel transmission-based approach based on a trio design using a simple logistic regression to test for association with a multivariate phenotype. We use our proposed method to analyze data on systolic and diastolic blood pressure levels provided in Genetic Analysis Workshop 18. However, we find that the bivariate analysis of the two phenotypes did not provide more promising results compared to univariate analyses, suggesting a possibility of a different set of major genetic variants modulating the two phenotypes. PMID:25519341

Haldar, Tanushree; Mukhopadhyay, Indranil; Ghosh, Saurabh

2014-01-01

65

High intensity interior aircraft noise increases the risk of high diastolic blood pressure in Indonesian Air Force pilots  

Directory of Open Access Journals (Sweden)

Full Text Available Aim: To analyze the effects of aircraft noise, resting pulse rate, and other factors on the risk of high diastolic blood pressure (DBP in Indonesian Air Force pilots.Methods: A nested case-control study was conducted using data extracted from annual medical check-ups indoctrination aerophysiologic training records at the Saryanto Aviation and Aerospace Health Institute (LAKESPRA in Jakarta from January 2003 – September 2008. For analysis of DBP: the case group with DBP ? 90 mmHg were compared with contral group with DBP < 79 mmHG. One case matched to 12 controls.Results: Out of 567 pilots, 544 (95.9% had complete medical records. For this analysis there were 40 cases of high DBP and 480 controls for DBP. Pilots exposed to aircraft noise 90-95 dB rather than 70-80 dB had a 2.7-fold increase for high DBP [adjusted odds ratio (ORa = 2.70; 95% confi dence interval (CI = 1.05-6.97]. Pilots with resting pulse rates of ? 81/minute rather than ? 80/minute had a 2.7-fold increase for high DBP (ORa = 2.66; 95% CI = 1.26-5.61. In terms of total fl ight hours, pilots who had 1401-11125 hours rather than 147-1400 hours had a 3.2-fold increase for high DBP (ORa = 3.18; 95% CI = 1.01-10.03.Conclusion: High interior aircraft noise, high total flight hours,  and high resting pulse rate, increased risk for high DBP. Self assessment of resting pulse rate can be used to control the risk of high DBP. (Med J Indones 2009; 276: 276-82Keywords: diastolic blood pressure, aircraft noise, resting pulse rate, military pilots

Minarma Siagian

2009-11-01

66

The influence of decreased low-molecular-weight heparin nadroparin dose on diastolic blood pressure in patients on hemodialysis.  

Science.gov (United States)

The aim of present study was to assess the impact of decreasing single bolus dose of nadroparin on blood pressure in patients on hemodialysis (HD). Forty HD patients were included in this study. The bolus dose of nadroparin was decreased twice by 25%; this lower dose was maintained for last 4 weeks, during which the dose was adjusted. There were no significant differences between the first and the last predialysis: systolic blood pressure ([pre-SBP]; 131.05 ± 25.58 vs 125.92 ± 25.49 mm Hg; P = .133), diastolic blood pressure ([pre-DBP]; 73.82 ± 11.82 vs 72.89 ± 9.13 mm Hg; P = .653), and pulse pressure ([pre-PP]; 57.24 ± 20.39 vs 53.03 ± 21.20 mm Hg; P = .121). We found correlation between delta nadroparin and pre-DBP in the last HD (rho = 0.310; P = .031) but not between delta nadroparin and pre-SBP and pre-PP values. This is the first report of influence of nadroparin dose lowering on pre-DBP in HD patients. PMID:22166588

Sain, Milenka; Ljutic, Dragan; Kovacic, Vedran; Radic, Josipa; Jelicic, Ivo

2012-09-01

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Arterial stiffness and 24 h ambulatory blood pressure monitoring in young healthy volunteers: the early vascular ageing Aristotle University Thessaloniki Study (EVA-ARIS Study).  

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Differences in 24 h blood pressure (BP) monitoring parameters such as average 24 h BP, day to night BP ratio and BP variability could have an impact in arterial stiffness. The study hypothesis was that despite similar average BP values in ambulatory blood pressure monitoring subjects with increased 24 h BP variability may have increased arterial stiffness. The study population consisted of 115 consecutive young healthy volunteers. Carotid-femoral PWV was measured in all subjects. Clinic BP was measured and an appropriate cuff was fitted on the non-dominant arm of each subject for a 24 h ambulatory blood pressure monitoring session. Waist to hip ratio as well as BMI was measured. Family history and smoking habits were recorded. In univariate analysis, estimated carotid-femoral PWV showed a significant correlation with age, weight, waist circumference, height, clinic systolic and diastolic BP, 24-h systolic and diastolic BP, 24-h pulse pressure, 24-h systolic and diastolic BP variability, daytime systolic and diastolic BP, daytime pulse pressure, daytime systolic and diastolic BP variability, nighttime systolic BP, nighttime pulse pressure and nighttime systolic BP variability. In multivariate regression analysis, age (B=0.95, P<0.001) and 24 h systolic BP variability (B=0.28, P<0.001) were independent determinanats of arterial stiffness. In conclusions, increased 24 h systolic BP variability is associated with arterial stiffness in young healthy volunteers. Pulse wave velocity in a young healthy population is useful to identify determinants of premature arterial stiffness, thus further elucidating the aspects of early vascular ageing. PMID:21840525

Kotsis, Vasilios; Stabouli, Stella; Karafillis, Ioannis; Papakatsika, Sofia; Rizos, Zoe; Miyakis, Spiros; Goulopoulou, Sofia; Parati, Gianfranco; Nilsson, Peter

2011-11-01

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Arterial blood pressure and vascular function in human saphenous vein.  

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Hypertension is a risk factor for accelerated saphenous vein (SV) graft disease and endothelial dysfunction in a number of vascular territories. We examined the relationship between blood pressure (BP) and vascular function in SV from 94 male patients undergoing coronary artery bypass grafting (CABG). Patients were pretreated with respect to cholesterol (3.4±1.2 mmol/L) and BP (systolic 139±22 mmHg, diastolic 74±13 mmHg). All patients were taking aspirin, 85% statins, 50% angiotensin-converting enzyme inhibitors and 70% beta-blockers. We demonstrate in human SV rings ex vivo that increased BP has no effect on acetylcholine-mediated vasodilatation (p=0.58), nor on the constrictor response to L-NMMA (p=0.98), but has a positive association with the constrictor response to phenylephrine (p=0.008) and a negative correlation with the vasodilator response to sodium nitroprusside (p=0.03). These results may provide further explanation for the high incidence of early vein graft failure after CABG in hypertensive patients and support an aggressive approach to optimize BP before surgery. PMID:24963039

Momin, A; Sharabiani, Mta; Wendler, O; Angelini, G D; Desai, J

2015-04-01

69

Characterization of Aging-Associated Cardiac Diastolic Dysfunction  

Science.gov (United States)

Aims Diastolic dysfunction is common in geriatric heart failure. A reliable parameter to predict myocardium stiffness and relaxation under similar end-diastolic pressure is being developed. We propose a material and mathematical model for calculating myocardium stiffness based on the concept of linear correlation between and wedge pressure. Methods and Results We enrolled 919 patients (male: ). Compared with the younger population of controls (mean age: years; ; male: ), the elderly (mean age: ; ; male: ) had a greater prevalence of hypertension, diabetes mellitus, and coronary artery disease (all ). We collected their M-mode and 2-D echocardiographic volumetric parameters, intraventricular filling pressure, and speckle tracking images to establish a mathematical model. The feasibility of this model was validated. The average early diastolic velocity of the mitral annulus assessed using tissue Doppler imaging was significantly attenuated in the elderly (: vs. ; ) and corresponded to the higher estimated wedge () pressure ( vs. ; ) in that cohort. E (Young's modulus) was calculated to describe the tensile elasticity of the myocardium. With the same intraventricular filling pressure, E was significantly higher in the elderly, especially those with values . Compared with diastolic dysfunction parameters, E also presented sentinel characteristics more sensitive for detecting early myocardial relaxation impairment, which indicates stiffer myocardium in aging hearts. Conclusion Our material and geometric mathematical model successfully described the stiffer myocardium in aging hearts with higher intraventricular pressure. Additional studies that compare individual differences, especially in health status, are needed to validate its application for detecting diastolic heart failure. PMID:24869961

Hung, Yung-Kung; Tsai, Wei-Chuan; Juang, Jer-Nan; Liu, Ping-Yen

2014-01-01

70

Determining the Arterial Blood Pressure of People Living in Yesilyurt Local Healthcare Office  

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Full Text Available AIM: Whereas the prevalance of arterial blood pressure which was a chronical health problem was 20%-25% among 30 year-old people, them showing an increase in aging, the percentage went as high as 50% in 60?s and later ages. What was that worrisome was that despite the high prevalance, only half of these received treathment. This is study was descriptively and cross-sectionally planned to determine whether the people asking their tensions to be measured in and around the Yesilyurt local healthcare office region. METHODS: The environment of the research consisted of 1400 people over 35 age and registered Yesilyurt Local healthcare Office and the whole of the environment were included in this sample. The study was conducted over 340 voluntaries. The data was collected by a questionnaire of 14 questions containing socio-demografic features and by measuring the arterial blood pressure, height and weight of the individuals. In the evaluation of the data, chi-square test was used and the level of significantly was accepted as 0.05. RESULTS: In this study, the rate of high sistolic blood pressure was found to be 21.47% and the rate of high diastolic blood pressure to be 8.23%. It was determined that age and body mass index varrieties were effective on sistolic hipertension. It was also found that in their behaviors of the use of hypertensive medicine, of regular arterial pressure controls and of having the hypertesion diagnosis significant differnces varied statistically on both sistolic and diastolic blood pressure people having. CONCLUSION: In order to improve the health, informative information abouth hypertension was provided for the participants for too days consisting of 4 sessions. [TAF Prev Med Bull 2009; 8(1.000: 53-58

Feyza Dereli

2009-02-01

71

Probing genetic overlap in the regulation of systolic and diastolic blood pressure in Danish and Chinese twins  

DEFF Research Database (Denmark)

Although the phenotypic correlation between systolic blood pressure (SBP) and diastolic blood pressure (DBP) is well known, the genetic basis for the correlation has rarely been investigated. The aim of this paper is to examine the genetic overlap between SBP and DBP by fitting bivariate models to Danish and Chinese twins and comparing ethnic differences between the two samples. Our estimates revealed a high proportion of additive genetic components shared by both SBP and DBP in Danish (0.71, 95% confidence interval (CI): 0.65-0.75) and Chinese (0.62, 95% CI: 0.50-0.71) twins with no statistically significant ethnic differences. The estimated genetic component in phenotypic correlation could serve to guide molecular genetic studies searching for genetic variants that affect both SBP and DBP. The bivariate model also estimated genetic and environmental contributions to SBP and DBP separately, with an overall pattern of higher genetic regulation or heritability in Danish (0.72, 95% CI: 0.67-0.76 for SBP; 0.70, 95% CI: 0.65-0.75 for DBP) than in Chinese (0.54, 95% CI: 0.44-0.63 for SBP; 0.57, 95% CI: 0.47-0.65 for DBP) twins and a higher contribution from unique environmental factors in Chinese compared with Danish twins. The estimated contribution from unique environmental factors suggests that promoting healthy lifestyles may provide an efficient way of controlling high blood pressure, particularly in the Chinese population.

Li, Shuxia; Pang, Zengchang

2014-01-01

72

Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma  

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Full Text Available Introduction. An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. Objective. The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP in women and men with primary open angle glaucoma. Methods. The study included 60 patients (33 males and 27 females older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, >25 mm Hg. They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. Results. Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end- diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. Conclusion. There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure. The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

Marjanovi? Ivan

2013-01-01

73

Valores de presión arterial en escolares sanos de una escuela primaria del municipio Cerro / Arterial pressure values in healthy students from a primary school of Cerro municipality  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish INTRODUCCIÓN: la hipertensión constituye un notable problema de salud en el ámbito mundial que determina una importante causa de morbilidad, en la que están involucrados factores genéticos y ambientales. La presión arterial en la infancia aumenta progresivamente a lo largo de los años, y es una impo [...] rtante variable a considerar. OBJETIVO: caracterizar el comportamiento de algunas variables cardiovasculares y nutricionales en escolares supuestamente sanos. MÉTODOS: se realizó un estudio de tipo descriptivo de cohorte transversal, en el que fueron estudiados escolares supuestamente sanos de una escuela primaria del municipio Cerro, en Ciudad de La Habana, en el período comprendido desde el 1ro. de diciembre de 2006 al 28 de febrero de 2007. El universo estuvo constituido por 358 niños de ambos sexos entre 5 y 11 años de edad. Las variables estudiadas fueron: presión arterial sistólica, presión arterial diastólica, presión arterial media, frecuencia cardiaca, peso, talla e índice de masa corporal. RESULTADOS: los resultados muestran cifras de presión arterial sistólica entre 77 y 104 mmHg, valores de presión arterial diastólica entre 43 a 64 mmHg, mientras que los valores de presión arterial media oscilan en un intervalo de 57 a 72 mmHg. La frecuencia cardiaca fue mayor en escolares de menor edad con respecto a los de mayor edad. El peso, la talla y el índice de masa corporal se incrementan con la edad. CONCLUSIONES: se concluye que los valores de presión arterial sistólica, diastólica y media en escolares de ambos sexos se incrementan con la edad, no así los de frecuencia cardiaca, cuya tendencia es a disminuir a medida que la edad aumenta. Los valores que corresponden al índice de masa corporal se elevan con la edad. Abstract in english INTRODUCTION: hypertension is a marked health problem at world scale determining significant causes of morbidity, in which are involved genetic and environmental factors. Infantile arterial pressure increases progressively during years, and it is a significant variable to be considered. AIM: to char [...] acterize behavior of some cardiovascular and nutritional variables in supposedly healthy students. METHODS: authors made a cross-sectional descriptive study in supposedly health students from a primary school of Cerro municipality in Havana City from December 1st 2006 to February 28, 2007. Sample included 358 children of both sexes aged between 5 and 11. Study variable were: systolic high blood pressure, diastolic arterial pressure, mean arterial pressure, cardiac frequency, weight, height and body mass index (BMI). RESULTS: results show figures of systolic arterial pressure between 77 and 104 mmHg, diastolic arterial pressure between 43 and 64 mmHg, whereas mean arterial pressure oscillate in a interval of 57-72 mmHg. Cardiac frequency was greater in younger ones regarding those oldest. Weight, height and MBI increase with age. CONCLUSIONS: we conclude that systolic, diastolic and mean arterial pressure in students of both sexes increase with age, but not cardiac frequency, whose trend is to decrease insofar as age increases. Values corresponding to BMI increase with age.

Roberto Francisco, Corredera Guerra; Yanet, Villar Badía; Tania Rosa, González Rodríguez; Reynaldo, Gómez Urbina.

2009-03-01

74

Knowledge of blood pressure levels and targets in patients with coronary artery disease in the USA.  

Science.gov (United States)

Little is known about patient awareness of nationally recommended blood pressure targets, especially among patients with cardiac disease. To examine this issue, we interviewed 738 patients hospitalized with coronary artery disease to assess their knowledge of their systolic and diastolic blood pressure levels as well as corresponding national targets. We used bivariate and multivariate analyses to determine if any patient demographic or clinical characteristics were associated with blood pressure knowledge. Only 66.1% of patients could recall their own systolic and diastolic blood pressure levels. Only 48.9% of all patients could correctly name targets for these values. Knowledge of target blood pressure levels was particularly poor among patients who were female (odds ratio (OR) 0.69; 95% confidence interval (CI) 0.49-0.98), aged > or =60 years (OR 0.70, CI 0.51-0.97), without any college education (OR 0.48, CI 0.35-0.65), without a documented history of hypertension (OR 0.57, CI 0.39-0.84), and with known diabetes (OR 0.46, CI 0.33-0.66). Patients in the highest risk group, according to Joint National Committee guidelines stratification, were no more knowledgeable about their blood pressure levels and targets than lower risk patients. A significant proportion of patients hospitalized with coronary artery disease do not know their own blood pressure levels or targets. Current blood pressure education efforts appear inadequate, particularly for certain patient subgroups in which hypertension is an important modifiable risk factor. PMID:16049521

Cheng, S; Lichtman, J H; Amatruda, J M; Smith, G L; Mattera, J A; Roumanis, S A; Krumholz, H M

2005-10-01

75

Influence of the elevation of the left ventricular diastolic pressure on the values of the first temporal derivative of the ventricular pressure (dP/dt)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english PURPOSE: To assess the effects of the elevation of the left ventricular end-diastolic pressure (LVEDP) on the value of the 1st temporal derivative of the ventricular pressure (dP/dt). METHODS: Nineteen anesthetized dogs were studied. The dogs were mechanically ventilated and underwent thoracotomy wi [...] th parasympathetic nervous system block. The LVEDP was controlled with the use of a perfusion circuit connected to the left atrium and adjusted to the height of a reservoir. The elevation of the LVEDP was achieved by a sudden increase in the height of a reservoir filled with blood. Continuous recordings of the electrocardiogram, the aortic and ventricular pressures and the dP/dt were performed. RESULTS: Elevation of the LVEDP did not result in any variation of the heart rate (167±16.0bpm, before the procedure; 167±15.5bpm, after the procedure). All the other variables assessed, including systolic blood pressure (128±18.3mmHg and 150±21.5mmHg), diastolic blood pressure (98±16.9mmHg and 115±19.8mmHg), LVEDP (5.5±2.49 and 9.3±3.60mmHg), and dP/dt (4,855 ± 1,082 mmHg/s and 5,149±1,242mmHg/s) showed significant increases following the expansion of the ventricular cavity. Although the elevation of the dP/dt was statistically significant, 6 dogs curiously showed a decrease in the values of dP/dt. CONCLUSION: Sudden elevation of the LVEDP resulted in increased values of dP/dt; however, in some dogs, this response was not uniform.

Katashi, Okoshi; José Roberto, Fioretto; Rossano César, Bonatto; Maria Teresinha Trovarelli, Tornero; Paulo José, Tucci.

1999-07-01

76

Influence of the elevation of the left ventricular diastolic pressure on the values of the first temporal derivative of the ventricular pressure (dP/dt  

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Full Text Available PURPOSE: To assess the effects of the elevation of the left ventricular end-diastolic pressure (LVEDP on the value of the 1st temporal derivative of the ventricular pressure (dP/dt. METHODS: Nineteen anesthetized dogs were studied. The dogs were mechanically ventilated and underwent thoracotomy with parasympathetic nervous system block. The LVEDP was controlled with the use of a perfusion circuit connected to the left atrium and adjusted to the height of a reservoir. The elevation of the LVEDP was achieved by a sudden increase in the height of a reservoir filled with blood. Continuous recordings of the electrocardiogram, the aortic and ventricular pressures and the dP/dt were performed. RESULTS: Elevation of the LVEDP did not result in any variation of the heart rate (167±16.0bpm, before the procedure; 167±15.5bpm, after the procedure. All the other variables assessed, including systolic blood pressure (128±18.3mmHg and 150±21.5mmHg, diastolic blood pressure (98±16.9mmHg and 115±19.8mmHg, LVEDP (5.5±2.49 and 9.3±3.60mmHg, and dP/dt (4,855 ± 1,082 mmHg/s and 5,149±1,242mmHg/s showed significant increases following the expansion of the ventricular cavity. Although the elevation of the dP/dt was statistically significant, 6 dogs curiously showed a decrease in the values of dP/dt. CONCLUSION: Sudden elevation of the LVEDP resulted in increased values of dP/dt; however, in some dogs, this response was not uniform.

Okoshi Katashi

1999-01-01

77

Stenosis of a Reconstructed Aorta Caused a Paradoxical Diastolic Pressure Gradient After Norwood Operation  

OpenAIRE

An infant with hypoplastic left heart syndrome showed paroxysmal episodes of bradycardia, hypotension, and hypoxemia upon crying after modified Norwood operation. Echocardiography showed decreased right ventricular ejection with grade III tricuspid regurgitation, a markedly enlarged aortic arch, and accelerated blood flow distal to the enlarged aorta. Aortography demonstrated an aneurysmal neo-aorta with an apple-shaped appearance. The pressure measurements revealed intriguing aortic hemodyna...

Satoshi Masutani; Hideaki Senzaki; Hirofumi Saiki; Hirotaka Ishido

2012-01-01

78

Cerebral vasospasm affects arterial critical closing pressure.  

Science.gov (United States)

The effect of cerebral vasospasm (CVS) after aneurysmal subarachnoid hemorrhage (SAH) on critical closing pressure (CrCP) has not been fully delineated. Using cerebral impedance methodology, we sought to assess the behavior of CrCP during CVS. As CrCP expresses the sum of intracranial pressure (ICP) and vascular wall tension, we also explored its role in reflecting changes in vascular tone occurring in small vessels distal to spasm. This retrospective analysis was performed using recordings from 52 patients, diagnosed with CVS through transcranial Doppler measurements. Critical closing pressure was calculated noninvasively using arterial blood pressure and blood flow velocity. Outcome was assessed at both discharge and 3 months after ictus with the Glasgow Outcome Scale. The onset of CVS caused significant decreases in CrCP (P=0.025), without any observed significant changes in ICP (P=0.134). Vasospasm induced asymmetry, with CrCP ipsilateral to CVS becoming significantly lower than contralateral (P=0.025). Unfavorable outcomes were associated with a significantly lower CrCP after the onset of CVS (discharge: P=0.014; 3 months after SAH: P=0.020). Critical closing pressure is reduced in the presence of CVS in both temporal and spatial assessments. As ICP remained unchanged during CVS, reduced CrCP most probably reflects a lower wall tension in dilated small vessels distal to spasm. PMID:25465041

Varsos, Georgios V; Budohoski, Karol P; Czosnyka, Marek; Kolias, Angelos G; Nasr, Nathalie; Donnelly, Joseph; Liu, Xiuyun; Kim, Dong-Joo; Hutchinson, Peter J; Kirkpatrick, Peter J; Varsos, Vassilis G; Smielewski, Peter

2015-02-01

79

Salt, Arterial Pressure, and Cardiovascular and Renal Damage  

OpenAIRE

This brief review deals with some novel developments regarding the possible role of salt in the pathogenesis of cardiovascular and renal disorders. Studies in both humans and experimental animals are discussed. Increased salt intake is usually associated with an increase in arterial pressure although some controversies still exist. Salt sensitivity of arterial pressure (defined as an increase in arterial pressure on dietary salt overload) was demonstrated in many animal species as well as in ...

Susic, Dinko; Fares, Hassan; Frohlich, Edward D.

2009-01-01

80

Results of ambulatory arterial blood pressure monitoring in children with obesity  

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Full Text Available Objectives: The relationship between obesity and essential hypertension is well known. In this study, we aimed to evaluate ambulatory arterial blood pressure monitoring of obese and non-obese children who had similar demographic characteristics.Materials and methods: Seventy one children and adolescents (n=39 obesity, n=32 controls were studied. Blood pressure of the children were measured by 24 hour ambulatory blood pressure monitoring device.Results: Obese children had significantly higher mean blood pressure values (systolic 121.9±11.7 mmHg, diastolic 70.2±5.3 mmHg than control subjects (systolic 109.3±6.7 mmHg, diastolic 65.1±4.6 mmHg, p0.05. Blood pressure load was found to be increased in obese children compared to the controls (%13.6±12.9 and %2.6±3.4, respectively; p<0.05. Serum total cholesterol and LDL-cholesterol levels of obese children (181.1±33.4 and 131.1±23.1mg/dl were significantly higher than those of the controls (134.3±11.1 and 103.3±14.2 mg/dl, p<0.05.Conclusions: Obesity in children and adolescents should not be regarded as variations of normality, but as abnormality with an extremely high risk for the development of hypertension and hyperlipidemia in adulthood.

Faruk Öktem

2010-12-01

81

Effects of mercury on the arterial blood pressure of anesthetized rats  

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Full Text Available SciELO Brazil | Language: English Abstract in english The available data suggests that hypotension caused by Hg2+ administration may be produced by a reduction of cardiac contractility or by cholinergic mechanisms. The hemodynamic effects of an intravenous injection of HgCl2 (5 mg/kg) were studied in anesthetized rats (N = 12) by monitoring left and ri [...] ght ventricular (LV and RV) systolic and diastolic pressures for 120 min. After HgCl2 administration the LV systolic pressure decreased only after 40 min (99 ± 3.3 to 85 ± 8.8 mmHg at 80 min). However, RV systolic pressure increased, initially slowly but faster after 30 min (25 ± 1.8 to 42 ± 1.6 mmHg at 80 min). Both right and left diastolic pressures increased after HgCl2 treatment, suggesting the development of diastolic ventricular dysfunction. Since HgCl2 could be increasing pulmonary vascular resistance, isolated lungs (N = 10) were perfused for 80 min with Krebs solution (continuous flow of 10 ml/min) containing or not 5 µM HgCl2. A continuous increase in pulmonary vascular resistance was observed, suggesting the direct effect of Hg2+ on the pulmonary vessels (12 ± 0.4 to 29 ± 3.2 mmHg at 30 min). To examine the interactions of Hg2+ and changes in cholinergic activity we analyzed the effects of acetylcholine (Ach) on mean arterial blood pressure (ABP) in anesthetized rats (N = 9) before and after Hg2+ treatment (5 mg/kg). Using the same amount and route used to study the hemodynamic effects we also examined the effects of Hg2+ administration on heart and plasma cholinesterase activity (N = 10). The in vivo hypotensive response to Ach (0.035 to 10.5 µg) was reduced after Hg2+ treatment. Cholinesterase activity (µM h-1 mg protein-1) increased in heart and plasma (32 and 65%, respectively) after Hg2+ treatment. In conclusion, the reduction in ABP produced by Hg2+ is not dependent on a putative increase in cholinergic activity. HgCl2 mainly affects cardiac function. The increased pulmonary vascular resistance and cardiac failure due to diastolic dysfunction of both ventricles are factors that might contribute to the reduction of cardiac output and the fall in arterial pressure.

L.V., Rossoni; S.M.C., Amaral; P.F., Vassallo; A., França; E.M., Oliveira; K.J., Varner; J.G., Mill; D.V., Vassallo.

1999-08-01

82

Downstream Hepatic Arterial Blood Pressure Changes Caused by Deployment of the Surefire AntiReflux Expandable Tip  

International Nuclear Information System (INIS)

Purpose: The purpose of this work was to evaluate blood pressure changes caused by deployment of the Surefire antireflux expandable tip. The pressure measurements are relevant because they imply changes in hepatoenteric arterial blood flow within this liver compartment during hepatic artery delivery of cytotoxic agents. Methods: After positioning the Surefire antireflux system in the targeted hepatic artery, blood pressure was obtained initially with the tip collapsed (or through a femoral artery sheath), then again after the tip was expanded before chemoembolization or yttrium 90 (90Y) radioembolization. Results: Eighteen patients with liver malignancy underwent 29 procedures in 29 hepatic arteries (3 common hepatic, 22 lobar, 4 segmental). Systolic, diastolic, and mean blood pressure were all decreased by a mean of 29 mm Hg (p = 0.000004), 14 mm Hg (p = 0.0000004), and 22 mm Hg (p = 0.00000001), respectively. Conclusion: When the Surefire expandable tip is deployed to prevent retrograde reflux of agents, it also results in a significant decrease in blood pressure in the antegrade distribution, potentially resulting in hepatopedal blood flow in vessels that are difficult to embolize, such as the supraduodenal arteries

83

Clinical echocardiographic indices of left ventricular diastolic function correlate poorly with pulmonary capillary wedge pressure at 1 year following heart transplantation.  

Science.gov (United States)

Clinical echocardiographic assessment of left ventricular (LV) systolic and diastolic function is routinely performed following orthotopic heart transplantation (OHT). The purpose of this study was to determine whether echocardiographic indices of LV diastolic function correlate with pulmonary capillary wedge pressure (PCWP) in the transplanted heart. Patients who had OHT between June 2009 and November 2011 underwent transthoracic echocardiography and right heart catheterization (RHC) at approximately 1 year post transplantation. We retrospectively assessed 33 potential parameters of LV diastolic function using 2-dimensional, spectral Doppler and tissue Doppler echocardiography. We measured PCWP by RHC. We compared echocardiographic measures with PCWP using linear regression analysis. Ninety-five patients (mean age 49 ± 13 years, 73 males, mean LV ejection fraction 62 ± 10 %) were included in the study. Overall, echocardiographic parameters of LV diastolic function demonstrated poor correlation with PCWP. By linear regression, the parameter that most strongly correlated with PCWP was left atrial (LA) minimum area in the apical 4-chamber view (p = 0.002, r(2) = 0.1). Comparing patients with PCWP ? 12 mmHg and those with PCWP > 12 mmHg, the parameter that demonstrated the most significant difference was LA minimum area in the apical 2-chamber view (p = 0.002), and comparing patients with PCWP ? 15 mmHg and those with PCWP > 15 mmHg, the most significant difference was peak early diastolic velocity of the mitral annulus (p = 0.02). In patients with cardiac allografts, clinical echocardiographic measures of LV diastolic function correlate poorly with PCWP. PMID:25701392

Okada, David R; Molina, Maria R; Kohari, Maria; Vorovich, Esther E; Owens, Anjali T; Han, Yuchi

2015-04-01

84

Rarefaction and blood pressure in systemic and pulmonary arteries.  

Science.gov (United States)

The effects of vascular rarefaction (the loss of small arteries) on the circulation of blood are studied using a multiscale mathematical model that can predict blood flow and pressure in the systemic and pulmonary arteries. We augmented a model originally developed for the systemic arteries (Olufsen et al. 1998, 1999, 2000, 2004) to (a) predict flow and pressure in the pulmonary arteries, and (b) predict pressure propagation along the small arteries in the vascular beds. The systemic and pulmonary arteries are modelled as separate, bifurcating trees of compliant and tapering vessels. Each tree is divided into two parts representing the `large' and `small' arteries. Blood flow and pressure in the large arteries are predicted using a nonlinear cross-sectional area-averaged model for a Newtonian fluid in an elastic tube with inflow obtained from magnetic resonance measurements. Each terminal vessel within the network of the large arteries is coupled to a vascular bed of small `resistance' arteries, which are modelled as asymmetric structured trees with specified area and asymmetry ratios between the parent and daughter arteries. For the systemic circulation, each structured tree represents a specific vascular bed corresponding to major organs and limbs. For the pulmonary circulation, there are four vascular beds supplied by the interlobar arteries. This manuscript presents the first theoretical calculations of the propagation of the pressure and flow waves along systemic and pulmonary large and small arteries. Results for all networks were in agreement with published observations. Two studies were done with this model. First, we showed how rarefaction can be modelled by pruning the tree of arteries in the microvascular system. This was done by modulating parameters used for designing the structured trees. Results showed that rarefaction leads to increased mean and decreased pulse pressure in the large arteries. Second, we investigated the impact of decreasing vessel compliance in both large and small arteries. Results showed, that the effects of decreased compliance in the large arteries far outweigh the effects observed when decreasing the compliance of the small arteries. We further showed that a decrease of compliance in the large arteries results in pressure increases consistent with observations of isolated systolic hypertension, as occurs in ageing. PMID:22962497

Olufsen, Mette S; Hill, N A; Vaughan, Gareth D A; Sainsbury, Christopher; Johnson, Martin

2012-08-01

85

Association of thyroid function with arterial pressure in normotensive and hypertensive euthyroid individuals: A cross-sectional study  

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Full Text Available Abstract Background Overt hypothyroidism has been associated with arterial hypertension and increased arterial stiffness. Results in euthyroid individuals have been conflicting. We investigated associations of thyroid function with systolic (SAP and diastolic (DAP arterial pressure in euthyroid subjects. Methods 311 euthyroid individuals (185 women, mean age 43.9 ± 9 without a history of diabetes attending a preventive medicine program were examined. Subjects receiving thyroxine (10.6% were excluded; 19.3% had hypertension, 43% had a family history for hypertension. TSH, fT4, thyroid autoantibodies, insulin, glucose were measured. The "fT4.TSH product", which has been suggested as a T4 resistance-index, was calculated. Results TSH range was 0.1–8, median 1.4 mU/L, fT4 range was 11.5–25.2 pmol/L, median 17.4. TSH and the "fT4.TSH product" were positively associated with DAP (p 2 mU/L (35.3% vs 21.3%, p = 0.045. Conclusion In euthyroid individuals the association of thyroid function with diastolic arterial pressure remains significant even when a stricter "normal range" for TSH levels is considered. The "freeT4.TSH" product appears to be an even stronger predictor of DAP, independently of HOMA insulin resistance index and obesity.

Saltiki Katerina

2008-09-01

86

Casein-Derived Lactotripeptides Reduce Systolic and Diastolic Blood Pressure in a Meta-Analysis of Randomised Clinical Trials  

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Full Text Available There is an urgent need to treat individuals with high blood pressure (BP with effective dietary strategies. Previous studies suggest a small, but significant decrease in BP after lactotripeptides (LTP ingestion, although the data are inconsistent. The study aim was to perform a comprehensive meta-analysis of data from all relevant randomised controlled trials (RCT. Medline, Cochrane library, EMBASE and Web of Science were searched until May 2014. Eligibility criteria were RCT that examined the effects of LTP on BP in adults, with systolic BP (SBP and diastolic BP (DBP as outcome measures. Thirty RCT met the inclusion criteria, which resulted in 33 sets of data. The pooled treatment effect for SBP was ?2.95 mmHg (95% CI: ?4.17, ?1.73; p < 0.001, and for DBP was ?1.51 mmHg (95% CI: ?2.21, ?0.80; p < 0.001. Sub-group analyses revealed that reduction of BP in Japanese studies was significantly greater, compared with European studies (p = 0.002 for SBP and p < 0.001 for DBP. The 24-h ambulatory BP (AMBP response to LTP supplementation was statistically non-significant (p = 0.101 for SBP and p = 0.166 for DBP. Both publication bias and “small-study effect” were identified, which shifted the treatment effect towards less significant SBP and non-significant DBP reduction after LTP consumption. LTP may be effective in BP reduction, especially in Japanese individuals; however sub-group, meta-regression analyses and statistically significant publication biases suggest inconsistencies.

Ágnes A. Fekete

2015-01-01

87

Is Nocturnal Systolic Blood Pressure Rise Associated with Central Hemodynamics and Arterial Stiffness?  

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Full Text Available OBJECTIVE: The aim of this study was to assess central hemodynamics and parameters of arterial stiffness of cases with nocturnal blood pressure rise. MATERIAL and METHODS: In this retrospective study, ambulatory blood pressure monitoring of 252 hypertensive patients was performed with the Mobil-O-Graph Arteriograph. RESULTS: 174 (%69.0 out of 252 patients were female and 78 (%31 were male and the mean age was 54.5±14.4. When Pearson's correlation test was performed, the nocturnal systolic blood pressure (SBP decline was associated with age (r=-0.169, p=0.008, diurnal pulse wave velocity (PWV (r=-0.179, p=0.005, nocturnal diastolic blood pressure (DBP decline (r=0.790, p<0.001, nocturnal central SBP (r=-0.410, p<0.001, and nocturnal augmentation index (Aix@75 (r=-0.215, p=0.001. When patients were divided into three groups as 10 % or more nocturnal SBP decline, less than 10 % nocturnal SBP decline and nocturnal SBP increase, there were statistically signifi cant differences regarding nocturnal pulse pressure (p<0.001, nocturnal DBP decline (p<0.001, nocturnal Aix@75 (p<0.001, and nocturnal peripheral resistance (p<0.001. CONCLUSION: We believe that strict follow up of conventional risk factors causing arterial stiffness in patients with less than 10 % nocturnal BP decline or increase and also the use of chronotherapy may be useful.

Gülperi ÇEL?K

2012-05-01

88

A new technique for assessing arterial pressure wave forms and central pressure with tissue Doppler  

OpenAIRE

Abstract Background Non-invasive assessment of arterial pressure wave forms using applanation tonometry of the radial or carotid arteries can be technically challenging and has not found wide clinical application. 2D imaging of the common carotid arteries is routinely used and we sought to determine whether arterial waveform measurements could be derived from tissue Doppler imaging (TDI) of the carotid artery. Methods We studied 91 subjects (52 men, age 52 ± 14 years) with and without cardio...

Carlier Stephane G; Mottram Phillip M; Jeffriess Leanne; Haluska Brian A; Marwick Thomas H

2007-01-01

89

Coronary artery disease, left ventricular hypertrophy and diastolic dysfunction are associated with stroke in patients affected by persistent non-valvular atrial fibrillation: a case-control study  

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Full Text Available Persistent non-valvular atrial fibrillation (NVAF is associated with an increased risk of cardiovascular events such as stroke, and its rate is expected to rise because of the ageing population. The absolute rate of stroke depends on age and comorbidity. Risk stratification for stroke in patients with NVAF derives from populations enrolled in randomized clinical trials. However, participants in clinical trials are often not representative of the general population. Many stroke risk stratification scores have been used, but they do not include transthoracic echocardiogram (TTE, pulsate wave Doppler (PWD and tissue Doppler imaging (TDI, simple and non-invasive diagnostic tools. The role of TTE, PWD and TDI findings has not been previously determined. Our study goal was to determine the association between TTE and PWD findings and stroke prevalence in a population of NVAF prone outpatients. Patients were divided into two groups: P for stroke prone and F for stroke free. There were no statistically significant differences between the two groups concerning cardiovascular risk factors, age (p=0.2, sex (p=0.2, smoking (p=0.3, diabetes (p=0.1 and hypercholesterolemia (p=0.2; hypertension was statistically significant (p less than 0.001. There were statistically significant differences concerning coronary artery disease, previous acute myocardial infarction (AMI (p less than 0.05 and non- AMI coronaropathy (p less than 0.04, a higher rate being in the P group. Concerning echo-Doppler findings, a higher statistically significant rate of left ventricular hypertrophy (LVH (p less than  0.05 and left ventricular diastolic dysfunction (p less than 0.001 was found in the P group and dilated left atrium (p less than  0.04 in the F group, the difference was not significant for mitral regurgitation (p=0.7. Stroke prone NVAF patients have a higher rate of hypertension, coronary artery disease, with and without AMI, LVH and left ventricular diastolic dysfunction, but not left atrial dilatation. M-B mode echocardiography and PWD examination help to identify high-risk stroke patients among NVAF subjects; therefore, they may help in the selection of appropriate therapy for each patient.

Andrea Passantino

2009-04-01

90

La hipertensión arterial en la tercera edad / High blood pressure in third age  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish A partir de la quinta o sexta décadas de la vida, la hipertensión arterial adopta formas y obedece a causas diferentes a las del niño o a las del adulto joven. En este caso, la presión arterial sistólica aumenta (> 140 mmHg) y la diastólica se mantiene o disminuye ([...] ión diferencial. La causa es la rigidez de las arterias de conductancia por la aterosclerosis y la acción de algunas hormonas como: adrenalina, noradrenalina, angiotensina II y aldosterona sobre la pared media arterial. El diagnóstico se hace constatando hipertensión sistólica aislada en pacientes mayores de 50 años. En jóvenes, además de la presión sistólica elevada con presión diastólica normal o baja, es conveniente medir otros indicadores de rigidez aórtica. La hipertensión sistólica en la tercera edad suele asociarse a: hipertrofia arterial y ventricular izquierda, disminución de la relajación de las paredes cardíacas y coronarias, isquemia miocárdica, nefrosclerosis, declinación cognoscitiva o incluso, demencia. El tratamiento requiere cuidados especiales y se debe adaptar a la frecuente comorbilidad de la edad avanzada. Los grupos antihipertensivos más efectivos, según ensayos al azar, son: los inhibidores de la enzima conversora de angiotensina, los bloqueadores de la angiotensina II, los antagonistas de la aldosterona y los bloqueadores de calcio. Los nitratos y los diuréticos se han empleado para reducir la presión sistólica, especialmente cuando concurre regurgitación valvular aórtica. La disminución de la presión sistólica, parece traer como consecuencia un retardo o detención de las complicaciones cardiovasculares, de la declinación cognoscitiva y de la demencia en pacientes de edad avanzada. Abstract in english From the fifth or sixth decades of life, high blood pressure adopts ways and is due to different causes to that of child or to that of young adult. In this case, systolic arterial pressure increases (> 140 mmHg), and the diastolic one remains or decreases ([...] ases. The cause is conduction artery stiffness by atherosclerosis as well as the action of some hormones including: adrenaline, noradrenaline, agiotensin II, and aldosterone on the arterial medium wall. Diagnosis is made verifying presence of an isolated systolic high blood pressure in patients aged over 50. In youngest, in addition to high systolic pressure with a normal or low diastolic pressure, it is advisable measurement of others indicators of aortic stiffness. Systolic pressure in third age may to be associated with: left ventricular and arterial hypertrophy, a relaxation decrease of cardiac and coronary walls, myocardial ischemia, nephroesclerosis, cognitive decline or even dementia. Treatment requires special cares and must to adjust to the frequent morbidity of old age. The more effective antihypertensive groups according to randomized assays include: agiotensin-converting enzyme (ACE) inhibitors, agiotensin II blockers, aldosterone antagonists, and calcium blockers. Nitrates and diuretic agents have been used to reduce systolic pressure, especially when there is an aortic valvular regurgitation. Decrease of systolic pressure to result in a delay or an arrest of cardiovascular complications, of cognitive decline, and dementia in third age patients.

David, García Barreto; Julio, Álvarez González; Raymid, García Fernández; Juan, Valiente Mustelier; Alberto, Hernández Cañero.

2009-06-01

91

Increased serum urea to creatinine ratio and its negative correlation with arterial pressure in canine babesiosis.  

Science.gov (United States)

The increase of the serum urea to creatinine ratio (UCR) was observed in dogs infected with Babesia canis. Previous studies have suggested that decrease of blood pressure can be one of the reasons for this phenomenon. In this work statistically significant increase of the UCR was observed in dogs with babesiosis. Comparison of the UCR between 23 azotaemic dogs and 25 non-azotaemic dogs infected with Babesia canis showed statistically significantly higher mean of the UCR in azotaemic dogs. Correlations between UCR and systolic, diastolic and mean arterial pressure (SAP, DAP and MAP) in 48 dogs infected with B. canis were negative (UCR and SAP: r = -0.3909; UCR and DAP: r = -0.3182; UCR and MAP: r = -0.3682) and statistically significant (p babesiosis. However, the correlations were not high, and there was no statistically significant correlation between UCR and arterial pressures in azotaemic dogs. Thus, it seems that decrease of blood pressure in dogs with babesiosis explains only partially the cause of increased UCR in infected dogs. The other authors suggested hyperureagenesis and myocardial injury as a potential reason for the increased UCR in canine babesiosis. Thus, further studies are needed to determine causes of increased UCR in dogs with babesiosis, especially on the connection between UCR changes and the concentrations of plasma cardiac troponins and ammonia, and the occurrence of occult blood on fecal examination. PMID:25119372

Zygner, Wojciech; Gójska-Zygner, Olga

2014-09-01

92

Machine Learning Techniques for Arterial Pressure Waveform Analysis  

OpenAIRE

The Arterial Pressure Waveform (APW) can provide essential information about arterial wall integrity and arterial stiffness. Most of APW analysis frameworks individually process each hemodynamic parameter and do not evaluate inter-dependencies in the overall pulse morphology. The key contribution of this work is the use of machine learning algorithms to deal with vectorized features extracted from APW. With this purpose, we follow a five-step evaluation methodology: (1) a custom-designed, non...

João Cardoso; Carlos Correia; Mariano Pego; Tânia Pereira; Catarina Pereira, H.; João Vieira; Pedro Santos; Almeida, Va?nia G.

2013-01-01

93

MONITORIZACIÓN AMBULATORIA DE LA PRESIÓN ARTERIAL, MÉTODOS, INDICACIONES Y UTILIDADES / AMBULATORY BLOOD PRESSURE MONITORING. METHODS, INDICATIONS AND UTILITIES  

Scientific Electronic Library Online (English)

Full Text Available Introducción. El exámen registra automáticamente la presión arterial en el paciente, en forma intermitente, durante sus actividades habituales, en vigilia y en sueño; es útil para: diagnóstico de hipertensión arterial y valoración del efecto de los antihipertensivos. Objetivos. Mostrar resultados de [...] l registro de 24 horas de la presión arterial, sus indicaciones y utilidades y establecer frecuencia y valores de referencia. Métodos. Estudiados 245 pacientes. El registro fue dividido en dos periodos: vigilia y sueño. Se consideraron estudios validos, aquellos mayores a 40. Variables analizadas: edad, sexo, motivos de estudio: sospecha de hipertensión, de hipotensión y evaluación de tratamiento antihipertensivo, caida nocturna, cargas presóricas, alzas tensionales. Criterios de anormalidad: cifras de presión anormales, ausencia de caida nocturna, cargas presóricas mayores de 50%, alzas tensionales mayores a 3, hipotensión arterial. Resultados. Edad media, 52 años. Mujeres 63%. Sospecha de hipertensión 125, de hipotensión 9 y evaluación de tratamiento 111. En 14% no hubo caída nocturna. Cargas presóricas anormales en 27%. Alzas tensionales en 64%. Hipertensión de bata blanca en 33%. Presiones medias anormales en 23%. Tratamiento insuficiente en 69%. Resultados anormales en 70%, por presiones aumentadas en 36% , en 55% por alzas tensionales, en 6%,por hipotensión y en 2% por ausencia de caída nocturna. Conclusiones. Se muestra la experiencia inicial del registro ambulatorio de la presión arterial. Se menciona la utilidad del examen, para definir la variación circadiana y las presiones medias de 24 horas, sistólicas y diastólicas, en vigilia y en sueño. Abstract in english Introduction. The test automatically recorded blood pressure in the patient, intermittently, during their usual activities in wakefulness and sleep and is useful for diagnosing hypertension arterial and assessing the effect of the antihypertensive drugs. Objetives. Show, results of 24 hour record of [...] blood pressure, indications, Utilities and to establish frecuency an reference values. For study: suspicion of hypertension, hypotension and evaluation of antihypertensive treatment: sleeping blood pressure declines, blood pressure load, pressures peaks. Criteria of abnormality: Abnormal pressure levels, absence of sleeping blood pressure declines, pressure loads greater than 50%, pressure peaks greater than 3, low blood pressure. Results. Average age: 52. Women 63%. Suspected hipertensión 125, hypotension 9 and evaluation treatment 111. In 14% there was no sleeping blood pressure decline. Blood pressure loads abnormal 27%. Pressure peaks 64%. White coat hypertension 33%. Mean pressures abnormal 23%. Insufficient treatment 69%. Abnormal results 70%, increased presures in 36%, in 55% pressure peaks, hypotension in 6% and 2% for lack sleeping blood pressure declines. Conclusions. Shows the initial experience of the ambulatory recording arterial blood pressure. The usefulness of the test is mentioned, to define the circadian variation and the average pressures of 24 hours, systolic an diastolic, in waking and sleep.

Roberto, Lavadenz Morales.

94

Effect of angiotensin II blockade on central blood pressure and arterial stiffness in subjects with hypertension  

OpenAIRE

In hypertension, the blood pressure curve may be divided into two sets of components. The first set is mean arterial pressure, steady flow, and vascular resistance, thus acting on small arteries; the second set refers to large arteries, hence to pulse pressure, arterial stiffness, and wave reflections. The angiotensin-converting enzyme (ACE) inhibitor perindopril not only reduces mean arterial pressure but also acts specifically on pulse pressure. The effect on pulse pressure predominates on ...

Safar, Michel E.

2010-01-01

95

Evaluación de la presión arterial media durante la cirugía de implante dental / Evaluation of mean arterial blood pressure during dental implant surgery  

Scientific Electronic Library Online (English)

Full Text Available Introducción: Los eventos de estrés, como una cirugía bucal, pueden elevar los niveles de catecolaminas circulantes produciendo un alza en la presión arterial a niveles dañinos para el organismo. Nuestra investigación tiene como propósito determinar si existe una variación estadísticamente significa [...] tiva de la presión arterial durante la cirugía de implantes. Materiales y método: Se registró la presión arterial sistólica (PS) y diastólica (PD) a 30 individuos sometidos a una cirugía de implantes mediante un monitor Dinamap Pro 400. Se calculó el valor de la presión arterial media (PM) y, finalmente, se determinó la diferencia entre la PM inicial de cada individuo y el valor más alto de la PM alcanzado durante la cirugía. Resultados: El promedio de las PM iniciales fue de 91,452 mmHg y el promedio de las PM máximas alcanzadas durante la cirugía fue de 104,476 mmHg, existiendo diferencia estadísticamente significativa (p = 0,0005). Conclusión: Se observa un alza significativa en los valores de PM registrados en los individuos durante la cirugía de implantes, por lo que es importante considerar esta alza en todos los pacientes que serán sometidos a dicho procedimiento y más aún en aquellos que ya posean valores elevados de su presión arterial de manera a evitar posibles complicaciones. Abstract in english Introduction: The stress situations like an oral surgery can increase the blood catecholamines, producing an increased arterial blood pressure to levels that could damage health. This study attempt to determine whether there is a statistically significant variation in the arterial blood pressure dur [...] ing dental implant surgery. Materials and method: We registered the blood pressure - systolic (SP) and diastolic (DP)- to 30 subjects undergoing implant surgery with the Dina map Pro 400 monitor. We calculated the mean arterial blood pressure (MP) and finally we determined the difference between initial mean blood pressure and the highest blood pressure value reached at surgery. Results: The mean of the initial mean blood pressure was 91.452 mmHg and the mean of highest mean blood pressure reached during surgery was 104.476 mmHg, obtaining statistically significant differences (P=.0005). Conclusion: As there was a significant increase in the MP values recorded in subjects during dental implant surgery, this should be taken into account in all patients undergoing to this procedure, and particularly in those with hypertension, to avoid possible complications.

Rolando, Carrasco; Erita, Cordero; Ian, Goldberg; Benjamín, Martínez; Cristóbal, Pacheco.

2014-09-01

96

Dipeptidylpeptidase Inhibition Is Associated with Improvement in Blood Pressure and Diastolic Function in Insulin-Resistant Male Zucker Obese Rats  

OpenAIRE

Diastolic dysfunction is a prognosticator for future cardiovascular events that demonstrates a strong correlation with obesity. Pharmacological inhibition of dipeptidylpeptidase-4 (DPP-4) to increase the bioavailability of glucagon-like peptide-1 is an emerging therapy for control of glycemia in type 2 diabetes patients. Accumulating evidence suggests that glucagon-like peptide-1 has insulin-independent actions in cardiovascular tissue. However, it is not known whether DPP-4 inhibition improv...

Aroor, Annayya R.; Sowers, James R.; Bender, Shawn B.; Nistala, Ravi; Garro, Mona; Mugerfeld, Irina; Hayden, Melvin R.; Johnson, Megan S.; Salam, Muhammad; Whaley-connell, Adam; Demarco, Vincent G.

2013-01-01

97

Effects of smoking cessation on central blood pressure and arterial stiffness  

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Full Text Available Takeshi Takami1,Yoshihiko Saito21Department of Internal Medicine, Clinic Jingumae, Kashihara, Nara, Japan; 2First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, JapanPurpose: Smoking affects arterial stiffness, thus causing an elevation in central blood pressure (CBP. The present study was designed to examine whether smoking cessation treatment improved CBP and arterial stiffness.Patients and methods: We conducted an observational study of 70 patients receiving smoking cessation treatment. Before and 60 weeks after the start of a 12-week varenicline treatment, we measured brachial blood pressure, CBP, brachial-ankle pulse wave velocity (baPWV, normalized radial augmentation index (rAIx@75, left ventricular weight, and left ventricular diastolic function of each patient. The data were compared between the patients who succeeded in quitting smoking (smoking cessation group; n = 37 and those who failed to quit smoking (smoking group; n = 33.Results: Baseline characteristics were similar in both groups. Brachial blood pressure remained unchanged in both groups. CBP, baPWV, and rAIx@75 decreased significantly in the smoking cessation group, while these parameters showed no significant change in the smoking group. Thus, CBP, baPWV, and rAIx@75 showed greater decrease in the smoking cessation group than in the smoking group (CBP, ?7.1 ± 1.4 mmHg vs 1.2 ± 2.7 mmHg; P < 0.01; baPWV, ?204 ± 64 cm/s vs ?43 ± 72 cm/s; P < 0.01; rAIx@75, ?6.4 ± 2.8% vs ?1.0 ± 3.9%; P < 0.01. Left ventricular weight and left ventricular diastolic function remained unchanged in both groups.Conclusion: Patients in the smoking cessation group showed significant improvement in CBP, baPWV, and rAIx@75. These results indicate that smoking cessation can improve arterial stiffness and CBP.Keywords: central blood pressure, augmentation index, brachial-ankle pulse wave velocity, smoking cessation, varenicline

Takami T

2011-10-01

98

Dynamic Stress Analysis of the Arterial Wall Utilizing Physiological Pressure Waveforms  

OpenAIRE

Arterial diseases, promoted by alterations in arterial wall properties, are among the main causes of mortality. Mechanical stresses of the arterial wall caused by pulsatile luminal pressure define arterial function in normal and pathological conditions. This study aims to determine dynamic stress distribution in the arterial wall subjected to physiological pressure waveforms. Finite element models of a typical artery are developed to evaluate Von Misses stress in the arterial wall due to phys...

Khani, M. M.; Shadpour, M. T.; Delavarpour, S.; Naghizadeh, S.; Avolio, A.

2008-01-01

99

The effect of siesta in parameters of cardiac structure and in interpretation of ambulatory arterial blood pressure monitoring  

Scientific Electronic Library Online (English)

Full Text Available OBJECTIVE: To evaluate the influence of the siesta in ambulatory blood pressure (BP) monitoring and in cardiac structure parameters. METHODS: 1940 ambulatory arterial blood pressure monitoring tests were analyzed (Spacelabs 90207, 15/15 minutes from 7:00 to 22:00 hours and 20/20 minutes from 22:01 t [...] o 6.59hours) and 21% of the records indicated that the person had taken a siesta (263 woman, 52±14 years). The average duration of the siesta was 118±58 minutes. RESULTS: (average ± standard deviation) The average of systolic/diastolic pressures during wakefulness, including the napping period, was less than the average for the period not including the siesta (138±16/85±11 vs 139±16/86±11 mmHg, p5%. CONCLUSION: The siesta influenced the heart structure parameters and from a statistical point of view the average of systolic and diastolic pressures and the respective pressure loads of the wakeful period.

Marco A.M., Gomes; Angela M.G., Pierin; Décio, Mion Jr.

2000-04-01

100

The effect of siesta in parameters of cardiac structure and in interpretation of ambulatory arterial blood pressure monitoring  

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Full Text Available OBJECTIVE: To evaluate the influence of the siesta in ambulatory blood pressure (BP monitoring and in cardiac structure parameters. METHODS: 1940 ambulatory arterial blood pressure monitoring tests were analyzed (Spacelabs 90207, 15/15 minutes from 7:00 to 22:00 hours and 20/20 minutes from 22:01 to 6.59hours and 21% of the records indicated that the person had taken a siesta (263 woman, 52±14 years. The average duration of the siesta was 118±58 minutes. RESULTS: (average ± standard deviation The average of systolic/diastolic pressures during wakefulness, including the napping period, was less than the average for the period not including the siesta (138±16/85±11 vs 139±16/86±11 mmHg, p5%. CONCLUSION: The siesta influenced the heart structure parameters and from a statistical point of view the average of systolic and diastolic pressures and the respective pressure loads of the wakeful period.

Marco A.M. Gomes

2000-04-01

101

Early diastolic filling dynamics in diastolic dysfunction  

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Full Text Available Abstract Background The aim of the study was to determine the relationship between the rate of peak early mitral inflow velocity and the peak early diastolic mitral annular tissue velocities in normal controls and to compare them with subjects with diastolic dysfunction. Methods The relationship between early passive diastolic transmitral flow and peak early mitral annular velocity in the normal and in diastolic dysfunction was studied. Two groups comprising 22 normal controls and 25 patients with diastolic dysfunction were studied. Results Compared with the normal group, those with diastolic dysfunction had a lower E/A ratio (0.7 ± 0.2 vs. 1.9 ± 0.5, p 2 vs. 871 ± 128.1 cm/sec2, p Conclusions This investigation provides information on the acceleration of early diastolic filling and its relationship to mitral annular peak tissue velocity (Ea recorded by Doppler tissue imaging. It supports not only the premise that recoil is an important mechanism for rapid early diastolic filling but also the existence of an early diastolic mechanism in normal.

Crean Peter A

2003-07-01

102

[Potency disorders before and after pelvic artery reconstruction: objectification by measuring penile artery pressure].  

Science.gov (United States)

Penile artery pressure was measured in 38 patients before and after aorto-iliac reconstruction using the Doppler technique. In 14 patients a markedly reduced penile pressure was found preoperatively which was significantly enhanced in 71% after operation. In 16% of all cases postoperative penile pressure was lower than the preoperative value. An improvement of sexual impairment was observed in 37% of the patients, while 26% reported a decrease of sexual function after operation. The reason seems to be an operative damage to the preaortal nerve plexus in most cases. Therefore, in younger patients with unilateral iliac artery occlusive disease an extraanatomical reconstruction is recommended. PMID:6714015

Schweiger, H; Zirngibl, H; Raithel, D

1984-02-01

103

Dança de salão: respostas crônicas na pressão arterial de hipertensos medicados / Ballroom dance: chronic responses on blood pressure in medicated hypertensives  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese A importância da prática de exercícios físicos para portadores de hipertensão arterial sistêmica está bem estabelecida na literatura, entretanto, a Dança de Salão, neste contexto, tem sido pouco explorada. O objetivo do estudo foi verificar o efeito crônico da prática de dança de salão sobre a press [...] ão arterial sistêmica de hipertensos medicados. Considerou-se como amostra o número de medidas obtidas da pressão arterial dos pacientes durante a participação no programa de dança. Assim, 92 medidas da pressão arterial foram realizadas, sendo divididas em quatro grupos: 1) pressão arterial sistólica pré-programa; 2) pressão arterial sistólica pós-programa; 3) pressão arterial diastólica pré-programa e; 4) pressão arterial diastólica pós-programa. Utilizaram-se esfigmomanômetro de coluna de mercúrio e estetoscópio. Considerou-se o protocolo de mensuração da Diretriz Brasileira. A pressão arterial foi aferida antes e após cada sessão de dança. Os 23 hipertensos medicados estudados tinham idade média de 62,5±7 anos e 34,8% eram do sexo masculino. Quarenta sessões de dança foram realizadas, três vezes/semana, com duração de uma hora/sessão. O valor médio da pressão arterial sistólica pré-programa foi de 131,8±17mmHg e após 117,8±13mmHg com diferença estatística significativa (p Abstract in english The importance of physical exercise for patients with systemic hypertension is well established in the literature. However, ballroom dance has been little investigated in this context. The objective of this study was to determine the chronic effect of ballroom dance on blood pressure in medicated hy [...] pertensives. The sample was the number of blood pressure measurements obtained during the patients' participation in the dance program. Thus, 92 blood pressure measurements were taken and divided into four groups: 1) pre-session systolic blood pressure, 2) post-session systolic blood pressure, 3) pre-session diastolic blood pressure, 4) post-session diastolic blood pressure. We used a mercury sphygmomanometer and stethoscope. As measuring protocol, we considered the Brazilian Guidelines. Blood pressure was measured before and after each ballroom dance session. The mean age of the 23 medicated hypertensive patients studied was 62.5 ± 7 years and 34.8% of them were male. Forty sessions were held three times a week, lasting one hour/session. The mean pre-session systolic blood pressure was 131,8 ± 17mmHg and 117,8±13mmHg after the session, with statistically significant difference (p

Fernanda Christina de Souza, Guidarini; Isabel de Castro, Schenkel; Victor Carvalho, Kessler; Tânia Rosane Bertoldo, Benedetti; Tales de, Carvalho.

2013-04-01

104

Pressure natriuresis and the renal control of arterial blood pressure.  

Science.gov (United States)

The regulation of extracellular fluid volume by renal sodium excretion lies at the centre of blood pressure homeostasis. Renal perfusion pressure can directly regulate sodium reabsorption in the proximal tubule. This acute pressure natriuresis response is a uniquely powerful means of stabilizing long-term blood pressure around a set point. By logical extension, deviation from the set point can only be sustained if the pressure natriuresis mechanism is impaired, suggesting that hypertension is caused or sustained by a defect in the relationship between renal perfusion pressure and sodium excretion. Here we describe the role of pressure natriuresis in blood pressure control and outline the cascade of biophysical and paracrine events in the renal medulla that integrate the vascular and tubular response to altered perfusion pressure. Pressure natriuresis is impaired in hypertension and mechanistic insight into dysfunction comes from genetic analysis of blood pressure disorders. Transplantation studies in rats show that blood pressure is determined by the genotype of the kidney and Mendelian hypertension indicates that the distal nephron influences the overall natriuretic efficiency. These approaches and the outcomes of genome-wide-association studies broaden our view of blood pressure control, suggesting that renal sympathetic nerve activity and local inflammation can impair pressure natriuresis to cause hypertension. Understanding how these systems interact is necessary to tackle the global burden of hypertension. PMID:25107929

Ivy, Jessica R; Bailey, Matthew A

2014-09-15

105

Association of sleep duration with arterial blood pressure profile of Gujarati Indian adolescents  

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Full Text Available Background and Aim: Recently, National Health and Nutritional Examination Survey-1 data analysis found short sleep duration as a risk factor for hypertension in the U.S. population. However, since ethnic differences exist in the aetiopathogenesis of diseases, the current study was undertaken to study the effect of sleep duration on the blood pressure profile of Gujarati Indian adolescents. Materials and Methods: A cross-sectional study was conducted on 489 Gujarati Indian adolescents of age group 16-19 years studying in school and colleges in the local population. The participants were assessed for their sleep duration, physical activity status, body composition, blood pressure profile and cardiovascular reactivity. The sleep duration was reported by the subjects as the number of hours they slept on most of the nights in a week over the last one year. The observations of the study were then analyzed after grouping them into: 1 Adequate Sleep Duration at Night, ASDN (? 7 hrs and 2 Inadequate Sleep Duration at Night, ISDN (< 7 hrs groups. Student?s unpaired t-test was used to study if any significant difference (P< 0.05 existed between the groups. Results: No significant difference was found in Systolic blood pressure, Diastolic blood pressure, Pulse pressure and Mean arterial pressure between the ASDN group and the ISDN group. Physical activity status also did not differ between the two groups. However, adolescents of ISDN group showed a significantly higher level of adiposity and cardiovascular reactivity as compared to adolescents of ASDN group. Conclusion: Although short sleep duration is associated with a higher level of adiposity and cardiovascular reactivity in Gujarati Indian adolescents, it does not affect the resting blood pressure profile of these adolescents. However, longitudinal studies would be required to observe if the changes in adiposity and cardiovascular reactivity affect these adolescents in later life.

Shaikh Wasim

2010-01-01

106

Stratification of Ambulatory Blood Pressure Monitoring Findings by Cluster Analysis in Patients with Arterial Hypertension, Obesity and Albuminuria  

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Full Text Available The aim of the investigation was to study the characteristics of ambulatory blood pressure monitoring (ABPM indices in the combination of arterial hypertension (AH with obesity and albuminuria using cluster analysis. Material and Methods. The study involved 70 AH patients randomly chosen, aged from 23 to 71 years (mean age — 47.9 years. ABPM was performed before antihypertensive therapy administration. We estimated body mass index and albuminuria level. ABPM indices were stratified into clusters. Results. Clusters with normal heart rate prevailed in patients with normal weight and overweight, I degree obesity in all AH varuants. Hypertensive clusters with tachycardia were found to prevail in patients with II–III degree obesity. AH structure changed with body mass increase. In overweight and I degree obesity there grows the occurrence of systolic-diastolic AH clusters. In II–III degree obesity the clusters of systolic-diastolic and isolated diastolic AH were revealed less frequently than in normal body weight, while isolated systolic AH clusters were found more frequently. Their occurrence increased in patients with a high albuminuria level as well. Conclusion. ABPM data can be grouped into clusters, and their own pathogenic mechanisms of AH maintenance and regulation seem to prevail in each cluster. In overweight and I degree obesity patients the occurrence of systolic-diastolic AH increases. With obesity degree increase there is the tendency for heart rate rise, and hemodynamic AH variants are redistributed towards the increase of isolated systolic AH, which is likely to be due to the increase in AH severity with vascular wall remodeling progression. Isolated systolic AH prevalence is increasing not only in II–III degree obesity, but also in high albuminuria supporting the significance of systolic AH in albuminuria development. No interaction between albuminuria and heart rate was revealed.

S.V. Samoyavcheva

2013-11-01

107

Relation of pulse and systolic and mean blood pressure to severe renal artery stenosis in patients undergoing concurrent coronary and renal angiography.  

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Abrupt onset of renal ischemia is associated with increased blood pressure (BP), but it is unknown whether BP remains elevated in patients with chronic severe atherosclerotic renal artery stenosis (RAS). Patients undergoing coronary angiography who had concurrent renal angiography were divided into 3 groups: severe (stenosis ?70% diameter reduction), moderate (10%-69%), and minimal RAS. Aortic BP was measured at the time of angiography. Renal angiography was performed in 762 (5.4%) of 14,181 patients undergoing coronary angiography. The mean age was 62 ± 12 years, 52% were women, 93% had hypertension, and 42% had diabetes mellitus. Minimal, moderate, or severe RAS was found in 62%, 30%, and 9% of patients. Patients with minimal RAS were younger, less likely to have hypercholesterolemia or coronary artery disease, and had a lower creatinine than patients with severe RAS. Severe RAS was associated with a lower diastolic BP and mean BP and a higher pulse pressure (PP), but there was no difference in systolic BP or the number of antihypertensive medications between the 3 groups. The degree of RAS had a weak positive correlation with PP, a weak negative correlation with diastolic BP, and almost no correlation with systolic BP or mean BP. In multivariate linear regression analysis, there was an association between severity of RAS and PP but not with mean BP or systolic BP. In conclusion, PP, but not systolic BP, diastolic BP, mean BP, or number of antihypertensive medications, was elevated in patients with severe RAS. PMID:23523062

Bazemore, Taylor C; Meredith, Dane; Bumgarner, Joseph M; Stouffer, George A

2013-06-01

108

Relation of noninvasive parameters and pulmonary artery mean pressure in patients with chronic obstructive lung disease.  

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A series of 31 patients with various degrees of chronic obstructive pulmonary disease (COPD) underwent radionuclide ventriculography with right heart catheterization. The patients were divided into 2 groups on the basis of their reduction in forced expiratory volume in 1 s (FEV1). In patients with FEV1 greater than or equal to 1,300 ml (group 1) the oxygen partial pressure (PaO2) did not significantly change with exercise, while in patients with FEV1 less than or equal to 1,200 ml (group 2) the PaO2 significantly decreased (p less than 0.05) with exercise. The groups were significantly different from each other as to the correlation between hemodynamic and noninvasive parameters. In the resting state, the correlation between pulmonary artery mean pressure (PAP) and both residual volume to total lung capacity (RV/TLC) and PaO2 was close only in group 2. By contrast, the right ventricular end diastolic wall thickness (RWD) correlated closely with PAP in both groups. With exercise close correlations were observed between PAP and the noninvasive parameters: RWD, PaO2 and right ventricular ejection fraction in both groups. Arterial CO2 partial pressure (PaCO2) was only increased (greater than or equal to 45 mm Hg) in group 2. This parameter correlated moderately closely with PAP both in the resting and the exercise state only in group 2. The predictive value of PaCO2 greater than or equal to 45 mm Hg for estimation of PAP greater than 35 mm Hg during exercise was 100%. We conclude that separation of patients with COPD into groups with different impairments of the lung function parameter FEV1 can improve the correlation coefficients between noninvasive and invasive parameters. The exercise values obviously correlate more closely than the resting values. An increased value of echocardiographically determined RWD seems to be a reliable parameter for prediction of PAP. PMID:3402158

Seibold, H; Bunjes, D; Kohler, J; Schmidt, A

1988-01-01

109

The effects of dexmedetomidine administration on the pulmonary artery pressure and the transpulmonary pressure gradient after the bidirectional superior cavopulmonary shunt.  

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The hemodynamic effects of dexmedetomidine (DEX) on pulmonary artery pressure (PAP) are not fully understood in patients with a single-ventricle physiology. The objective of this retrospective study was to characterize the effect of perioperative DEX infusion on PAP and the transpulmonary pressure gradient after a bidirectional superior cavopulmonary shunt (BCPS) operation. We retrieved physiologic data including the heart rate, incidence of cardiac pacing, systolic and diastolic arterial blood pressure (ABP), and superior vena cava (SVC) and inferior vena cava (IVC) pressures from the medical records of all patients Kaye-Stansel procedure, those with additional pulmonary blood flow, and those without both a SVC and an IVC catheter were excluded from the present study. Following the BCPS operation, the SVC pressure is equivalent to the PAP. Similarly, the IVC pressure is equivalent to the common atrial pressure (CAP). Accordingly, we can directly assess the transpulmonary pressure gradient, defined as the difference between the PAP and the CAP, using simultaneous SVC and IVC pressure measurements. Twenty-nine patients were included in the present study. We did not find any increase in the PAP, CAP, PAP/systolic ABP ratio, or the transpulmonary pressure gradient as of 6 h after admission to the intensive care unit when the patients were treated with DEX infusion at a median (interquartile ranges) dose of 0.6 mcg/kg/h (0.4, 0.64 mcg/kg/h). We concluded that the administration of DEX to children with a single-ventricle physiology is acceptable. PMID:25113519

Nishibe, Shinichi; Imanishi, Hirokazu; Mieda, Tsutomu; Tsujita, Miki

2015-01-01

110

Mini invasive hemodynamic monitoring: from arterial pressure to cardiac output  

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Full Text Available To evaluate the Cardiac Output (CO the standard invasive pulmonary artery catheter (PAC is considered today the gold standard. The major criticism to the PAC is that its level of invasiveness is not supported by an improvement in patient's outcome. The interest to lesser and lesser invasive techniques is high. Therefore, the alternative techniques have been recently developed.Cardiac Output can be monitored continuously by different devices that analyze the arterial waveform to track changes in stroke volume (SV and CO. The analysis of the arterial pressure wave to determine cardiac output is classified as Pulse Contour analysis or Pulse Pressure Analysis. Starting from a similar principle three main devices are now available on the market, with different algorithms and features:• PiCCO System (Pulsion Medical System, Munich, Germany• LiDCOTM plus System (LidCO, Cambridge, UK• Flotrac technology and Vigileo Monitor (Edwards Lifesciences, Irvine, CA, USA.The algorithm used by all these devices has been also implemented even with the analysis of the variation of stroke volume (SVV and of the pulse pressure (PPV. SVV and PPV represent the variation of stroke volume and of the pulse pressure during the respiratory cycle. In sedated ventilated patients these indexes have proven to predict the response to a fluid challenge. A high variation (>10-12% identifies with good sensitivity and specificity responders and not responders.

GIORGIO DELLA ROCCA

2008-02-01

111

Sildenafil and diastolic dysfunction after acute myocardial infarction in patients with preserved ejection fraction  

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BACKGROUND: Diastolic dysfunction is frequently seen after myocardial infarction and is characterized by a disproportionate increase in filling pressure during exercise to maintain stroke volume. We hypothesized that sildenafil would reduce filling pressure during exercise in patients with diastolic dysfunction after myocardial infarction. METHODS AND RESULTS: Seventy patients with diastolic dysfunction and near normal left ventricular ejection fraction on echocardiography were randomly assigned sildenafil 40 mg thrice daily or matching placebo for 9 weeks. Before randomization and after 9 weeks of treatment patients underwent simultaneous echocardiography and right heart catheterization at rest and during exercise. Primary end point was pulmonary capillary wedge pressure, and secondary end points comprised cardiac index and pulmonary arterial pressure at rest and during exercise after 9 weeks. After 9 weeks there were no differences in pulmonary capillary wedge pressure at rest (13±4 versus 13±3 mm Hg, P=0.25) or at peak exercise (35±8 mm Hg versus 31±7 mm Hg, P=0.07). However, with treatment cardiac index increased at rest (P=0.006) and peak exercise (P=0.02) in the sildenafil group, and systemic vascular resistance index (resting, P=0.0002; peak exercise, P=0.007) and diastolic blood pressure (resting, P=0.005; peak exercise, P=0.02) were lower in the sildenafil group. Resting left ventricular end-diastolic volume index increased (P=0.001) within the sildenafil group but was unchanged in the placebo group. CONCLUSIONS: Sildenafil did not decrease filling pressure at rest or during exercise in post-myocardial infarction patients with diastolic dysfunction. However, there were effects on secondary end points, which require further studies.

Andersen, Mads J; ErsbØll, Mads

2013-01-01

112

Modeling left ventricular diastolic dysfunction: classification and key indicators  

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Full Text Available Abstract Background Mathematical modeling can be employed to overcome the practical difficulty of isolating the mechanisms responsible for clinical heart failure in the setting of normal left ventricular ejection fraction (HFNEF. In a human cardiovascular respiratory system (H-CRS model we introduce three cases of left ventricular diastolic dysfunction (LVDD: (1 impaired left ventricular active relaxation (IR-type; (2 increased passive stiffness (restrictive or R-type; and (3 the combination of both (pseudo-normal or PN-type, to produce HFNEF. The effects of increasing systolic contractility are also considered. Model results showing ensuing heart failure and mechanisms involved are reported. Methods We employ our previously described H-CRS model with modified pulmonary compliances to better mimic normal pulmonary blood distribution. IR-type is modeled by changing the activation function of the left ventricle (LV, and R-type by increasing diastolic stiffness of the LV wall and septum. A 5th-order Cash-Karp Runge-Kutta numerical integration method solves the model differential equations. Results IR-type and R-type decrease LV stroke volume, cardiac output, ejection fraction (EF, and mean systemic arterial pressure. Heart rate, pulmonary pressures, pulmonary volumes, and pulmonary and systemic arterial-venous O2 and CO2 differences increase. IR-type decreases, but R-type increases the mitral E/A ratio. PN-type produces the well-described, pseudo-normal mitral inflow pattern. All three types of LVDD reduce right ventricular (RV and LV EF, but the latter remains normal or near normal. Simulations show reduced EF is partly restored by an accompanying increase in systolic stiffness, a compensatory mechanism that may lead clinicians to miss the presence of HF if they only consider LVEF and other indices of LV function. Simulations using the H-CRS model indicate that changes in RV function might well be diagnostic. This study also highlights the importance of septal mechanics in LVDD. Conclusion The model demonstrates that abnormal LV diastolic performance alone can result in decreased LV and RV systolic performance, not previously appreciated, and contribute to the clinical syndrome of HF. Furthermore, alterations of RV diastolic performance are present and may be a hallmark of LV diastolic parameter changes that can be used for better clinical recognition of LV diastolic heart disease.

Ma Tony S

2011-05-01

113

Treinamento resistido controla a pressão arterial de ratos hipertensos induzidos por l-NAME / Resistance training controls arterial blood pressure in rats with L-NAME- induced hypertension  

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Full Text Available FUNDAMENTO: A hipertensão arterial é uma síndrome multifatorial, crônica, causada tanto por fatores congênitos ou adquiridos. OBJETIVO: Avaliar os efeitos do treinamento físico resistido (TR) sobre pressão arterial, reatividade e morfologia vascular de ratos hipertensos induzidos por L-NAME. MÉTODOS [...] : Ratos Wistar machos (200-250 g) foram divididos em 3 grupos: normotenso sedentário (NS), hipertenso sedentário (HS) e hipertenso treinado (HT). A hipertensão foi induzida pela administração de L-NAME (40 mg/kg) na água de beber por 4 semanas. A pressão arterial foi avaliada antes e após o TR. O TR foi realizado utilizando 50% de 1RM, em 3 séries de 10 repetições, 3 vezes por semana, durante quatro semanas. A reatividade vascular foi mensurada em artéria mesentérica superior por curvas concentração resposta ao nitroprussiato de sódio (NPS) e fenilefrina (FEN). Além disso, foram realizadas análises histológicas e estereológicas. RESULTADOS: O TR inibiu o aumento das pressões arteriais média e diastólica. Foi observada uma redução significativa na resposta máxima e na potência da FEN entre os grupos HS e HT. A análise histológica evidenciou aspecto normal para as túnicas íntima, média e adventícia em todos os grupos. Não houve diferença significativa nas áreas do lúmen, da túnica média e total das artérias dos grupos HS e HT em relação ao NS. A razão parede/lúmen arterial do grupo HS apresentou diferença significativa em relação ao NS (p Abstract in english BACKGROUND: Arterial hypertension is a multifactorial chronic condition caused by either congenital or acquired factors. OBJECTIVE: To evaluate the effects of Resistance Training (RT) on arterial pressure, and on vascular reactivity and morphology, of L-NAME-treated hypertensive rats. METHODS: Male [...] Wistar rats (200 - 250 g) were allocated into Sedentary Normotensive (SN), Sedentary Hypertensive (SH) and Trained Hypertensive (TH) groups. Hypertension was induced by adding L-NAME (40 mg/Kg) to the drinking water for four weeks. Arterial pressure was evaluated before and after RT. RT was performed using 50% of 1RM, 3 sets of 10 repetitions, 3 times per week for four weeks. Vascular reactivity was measured in rat mesenteric artery rings by concentration-response curves to sodium nitroprusside (SNP); phenylephrine (PHE) was also used for histological and stereological analysis. RESULTS: Resistance training inhibited the increase in mean and diastolic arterial pressures. Significant reduction was observed in Rmax (maximal response) and pD2 (potency) of PHE between SH and TH groups. Arteries demonstrated normal intima, media and adventitia layers in all groups. Stereological analysis demonstrated no significant difference in luminal, tunica media, and total areas of arteries in the SH and TH groups when compared to the SN group. Wall-to-lumen ratio of SH arteries was significantly different compared to SN arteries (p

Ayslan Jorge Santos de, Araujo; Anne Carolline Veríssimo dos, Santos; Karine dos Santos, Souza; Marlúcia Bastos, Aires; Valter Joviniano, Santana-Filho; Emerson Ticona, Fioretto; Marcelo Mendonça, Mota; Márcio Roberto Viana, Santos.

2013-04-01

114

Influence of Age and Arterial Blood Pressure on the Anti-hypertensive Action of Dihydro-pyridine Compounds in Hypertensive Patients  

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Full Text Available ABSTRACT To study the antihypertensive effect of dihydropyridines and correlate with the patient’s age, the degree of hypertension and mean arterial pressure, in three groups of eight hypertensive patients with mild, moderate and severe hypertension selected from the Clinical Pharmacology Unit of Va [...] rgas Hospital in Caracas. Mean age, weight and height of the selected patients were 55.66 ± 3.4, years, 67 ± 3.05 Kg and 1.63 ± 0.01 m, respectively. Three acute experimental designs compared with placebo were followed and each group of patients received amlodipine, nitrendipine or isradipine at different times, in single doses of 10, 20 and 5 mg, respectively. The cardiovascular parameters evaluated were: mean arterial pressure, systolic blood pressure, diastolic blood pressure and cardiac frequency at regular intervals during 48, 6 and 24 hours for amlodipine, nitrendipine and isradipine, respectively. Acute administration of amlodipine (10 mg) to hypertensive patients, significantly reduced blood pressure form 185 ± 11.21/100 ± 7.07 to 150.5 ± 10.6/88.6 ± 7.8 mmHg at 8 hours and to 162 ± 10.9/91 ± 5.6 mmHg at 48 hours. Cardiac frequency also increased significantly at 8 and 48 hours in 10 and 9 beats/min, respectively. There was a positive correlation between patient’s age and mean arterial pressure decrease and also between pretreatment and decreased arterial pressure. Two hours after acute administration of isradipine (5 mg) to hypertensive patients, blood pressure decreased significantly from 179.50 ± 7.6/100.26 ± 3.28 mmHg to 143.75 ± 4.7/82 ± 5.18 mmHg. Cardiac frequency increased in 5 beats/min at the same time of measure. There was a positive correlation between patient’s age and arterial pressure decrease and a slight but not significant correlation between pretreatment and mean arterial blood pressure decrease. Acute dose of nitrendipine (20 mg) to hypertensive patients induced a significant fall of arterial blood pressure from 172.25 ± 7.8/107.13 ± 3.58 to 134.5 ± 5.08/81 ± 5.84 mmHg two hours after the administration of the drug, and the cardiac frequency increased significantly in 11 beats/min during this time. There was no significant correlation between patient’s age and the mean arterial pressure fall, neither between pretreatment and the decrease of arterial blood pressure.

M, Bermúdez; E, Lezama; A, Luchsinger; F, Contreras; MA, De la Parte; Manuel, Velasco.

2000-07-01

115

Obese children and adolescents have elevated nighttime blood pressure independent of insulin resistance and arterial stiffness  

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BACKGROUND: Insulin resistance has been related to elevated blood pressure (BP) in obese children and may adversely affect the vasculature by arterial stiffening. The objective was to investigate whether daytime and nighttime BP were elevated and related to insulin resistance and arterial stiffness in obese children and adolescents. METHODS: Ninety-two obese patients aged 10-18 years were compared with 49 healthy control individuals. Insulin resistance was measured as the homeostatic assessment model (HOMA), and arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV). RESULTS: Mean ± SD daytime systolic BP (SBP) (obese: 125±8.3mm Hg; control: 121±10.1mm Hg; P = 0.03) and nighttime SBP (obese: 108±10.7mm Hg; control: 102±8.2mm Hg; P = 0.0001) were higher in the obese group when compared with the control group. No difference was found in daytime diastolic BP (DBP), whereas nighttime DBP (obese: 60±6.6mm Hg; control: 57±4.8mm Hg; P = 0.001) and night-to-day BP ratios were higher in the obese group. Nighttime SBP was related to BMI z score (? = 6.0; 95% confidence interval (CI) = 2.9-9.1; P = 0.0002) and waist/height ratio (? = 36.7; 95% CI = 5.6-67.9; P = 0.02) in the obese group. HOMA index (obese: median = 3.7, interquartile range (IQR) = 2.3-6.0; control: median = 2.6, IQR = 1.8-3.4; P = 0.002) was higher, whereas cfPWV (obese: 4.8±0.8 m/s; control: 5.1±0.6 m/s; P = 0.03) was lower in the obese group. CfPWV was not related to logHOMA index. In multiple regression analyses, the higher nighttime BP in the obese group was independent of logHOMA and cfPWV. CONCLUSIONS: Obese children had a higher nighttime BP when compared with the control group independently of insulin resistance and arterial stiffness. No relationship was found between insulin resistance and arterial stiffness. CLINICAL TRIAL REGISTRATION Clinicaltrials.gov identifier NCT01310088.

Hvidt, Kristian N; Olsen, Michael H

2014-01-01

116

Associação entre a Incisura Diastólica das Artérias Uterinas e a Histologia do Leito Placentário em Grávidas com Pré-eclâmpsia Association between Diastolic Notch of Uterine Artery and the Histology of the Placental Bed in Pregnant Women with Preeclampsia  

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Full Text Available Objetivo: avaliar a associação entre a presença da incisura diastólica nas artérias uterinas maternas e as alterações histopatológicas dos vasos útero-placentários. Métodos: estudo transversal incluindo 144 pacientes com gestação única interrompida por via abdominal entre a 27ª e a 41ª semana. Destas, 84 gestações estavam associadas à pré-eclâmpsia e 60 não apresentaram intercorrências clínicas. Neste grupo realizou-se dopplerfluxometria de ambas as artérias uterinas e biópsia do leito placentário. Resultados: das 144 pacientes, 88 (61% tiveram o fragmento da biópsia considerado representativo do leito placentário. A incisura diastólica estava presente em 40 (70% dos casos de alterações fisiológicas inadequadas e ausente em 28 (90% dos casos de alterações fisiológicas presentes (p=0,05. A dopplerfluxometria apresentou sensibilidade de 70%, especificidade de 90% e valores preditivos positivo e negativo de 44 e 97%, respectivamente. A associação entre a presença de incisura diastólica bilateral das artérias uterinas e arteriopatia decidual também foi significativa (dos 25 casos de arteriopatia decidual a incisura estava presente em 24, p=0,05. A sensibilidade da dopplerfluxometria foi de 96%, especificidade de 70% e valores preditivos positivo e negativo de 26 e 99%, respectivamente, ao passo que para a arteriolosclerose a dopplerfluxometria apresentou sensibilidade de 80%, especificidade de 55% e valores preditivos positivo e negativo de 17 e 96%, respectivamente. Conclusões: a incisura diastólica nas artérias uterinas maternas é indicador seguro de vasculopatia no leito placentário. A adequada invasão trofoblástica do leito placentário, revelada por histologia típica de alterações fisiológicas, resulta na ausência de incisura diastólica bilateral das artérias uterinas maternas.Purpose: to evaluate the association between the presence of diastolic notch in the maternal uterine arteries, and the histopathological changes of the uteroplacental vessels. Methods: transversal study of 144 women with single pregnancy interrupted by cesarean section between 27 and 41 weeks. In this sample, 84 had pregnancies complicated by preeclampsia and the other 60 were normal. In this group, Doppler study of both uterine arteries and placental bed biopsy was performed. Results: of the total of 144 patients, 88 patients (61% had a biopsy fragment that was considered representative of the placental bed. The diastolic notch was present in 40 patients (70% of the total of cases with inadequate physiologic alterations and absent in 28 patients (90% of the total of cases with physiologic alterations (p=0.0000. The Doppler study showed 70% sensitivity, 90% specificity, 44% positive predictive value and 97% negative predictive value. The association between bilateral diastolic notch of uterine arteries and acute atherosis in the placental bed was also significant (24 out of 25 cases -- p=0.000. The Doppler study showed 96% sensitivity, 70% specificity, 26% positive predictive value and 99% negative predictive value, while for arteriolosclerosis its results were 80% sensitivity, 55% specificity, 17% positive predictive value and 96% negative predictive value. Conclusions: the diastolic notch in the maternal uterine is a safe indicator of pathological vessel alteration in the placental bed. The adequate trophoblast migration into the myometrium, revealed by physiologic changes, results in the absence of bilateral diastolic notch of the maternal uterine arteries.

Regina Amélia Lopes Pessoa de Aguiar

2001-08-01

117

Monitorização ambulatorial da pressão arterial em pacientes normotensos com hipotireoidismo subclínico / Ambulatory blood pressure monitoring in normotensive patients with subclinical hypothyroidism  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese FUNDAMENTO: O hipotireoidismo manifesto está associado com elevação da pressão arterial diastólica; entretanto, a associação entre o hipotireoidismo subclínico (HS) e alteração da pressão arterial (PA) é desconhecida. OBJETIVO: O objetivo do presente estudo foi avaliar a monitorização ambulatorial d [...] a pressão arterial (MAPA) por 24 horas em pacientes normotensos com HS em comparação a indivíduos normotensos eutireóideos (EU). MÉTODOS: Foi realizado um estudo transversal com 50 participantes (HS = 30 e EU = 20) que não apresentavam diferenças em relação a fatores de risco para hipertensão. A monitorização ambulatorial de pressão arterial foi realizada com um monitor Dynamapa®, utilizando-se um método oscilométrico validado pela AAMI (Association for the Advancement of Medical Instrumentation) e pela BHS (British Hypertension Society). RESULTADOS: Os níveis séricos médios de TSH e T4 livre foram respectivamente 6,9 ± 2,2 µUI/ml e 1,1 ± 0,2 ng/dl em pacientes com HS. Apesar de não haver diferença em relação à média da pressão arterial sistólica e diastólica entre os dois grupos, houve uma correlação positiva entre os níveis de pressão arterial diastólica média (PADM) e os valores séricos de TSH em pacientes com HS (r:0,477; p = 0,004). Essa correlação foi detectada por medidas diurnas (r:0,498; p = 0,002) e noturnas (r:0,322; p = 0,032). CONCLUSÃO: A pressão arterial não diferiu entre pacientes com ou sem HS; contudo, os resultados sugerem que a progressão de hipotireoidismo subclínico para níveis mais elevados de TSH pode aumentar o risco cardiovascular através do aumento da pressão arterial diastólica. Abstract in english BACKGROUND: Overt hypothyroidism is associated with elevation of diastolic blood pressure; however the association of subclinical hypothyroidism (SH) with arterial blood pressure (ABP) alteration is unknown. OBJECTIVE: The aim of the present study was to evaluate ambulatory blood pressure monitoring [...] (ABPM), over 24 hours, in normotensive patients with SH in comparison to euthyroid (EU) normotensive individuals. METHODS: A cross-sectional study was performed with 50 participants (SH = 30 and EU = 20) that did not differ regarding risk factors for hypertension. The ABPM was carried out with a DINAMAPA TM monitor, using the oscillometric method validated by AAMI (Association for the Advancement of Medical Instrumentation) and by the BHS (British Hypertension Society). RESULTS: The mean serum TSH and FT4 were respectively 6.9 ± 2.2 µUI/ml and 1.1 ± 0.2 ng/dl in SH patients. Although there was no difference in the mean values of systolic and diastolic blood pressure between the two groups, there was a positive correlation between the mean values of diastolic blood pressure (DBP) and serum TSH levels in SH patients (r:0.477; p = 0.004). These correlations were detected at daytime (r:0.498; p = 0.002) and sleep-time (r:0.322; p = 0.032) measurements. CONCLUSION: The blood pressure was not different between patients with or without SH; however, the results suggest that the progression of subclinical hypothyroidism to higher levels of TSH may increase the cardiovascular risk by increasing diastolic blood pressure.

Marcia Martins, Ferreira; Patricia de Fatima dos Santos, Teixeira; Vera Aleta R., Mansur; Vaneska Spinelli, Reuters; Cloyra Paiva, Almeida; Mario, Vaisman.

2010-06-01

118

Comportamiento de la presión pulmonar y función del ventrículo derecho intraesfuerzo / Pulmonary Artery Pressure and Right Ventricular Function during Exercise  

Scientific Electronic Library Online (English)

Full Text Available Introducción El comportamiento fisiológico de la presión pulmonar durante el ejercicio continúa sin establecerse con precisión. La literatura es discordante con respecto a los valores considerados patológicos de presión pulmonar intraesfuerzo (PPI) en ausencia de valvulopatía mitral e incluso, las ú [...] ltimas guías no recomiendan utilizar la presión pulmonar media ? 30 mmHg con el esfuerzo para definir hipertensión pulmonar. Es escasa la información disponible en relación a la respuesta hemodinámica y funcional del ventrículo derecho (VD) con el esfuerzo y tampoco sobre el hecho de si podría discriminar entre una respuesta fisiológica o patológica de la presión pulmonar. Objetivo Determinar el comportamiento de la PPI y comparar los parámetros ecocardiográficos de función sistólica y diastólica del VD en relación a sus niveles. Material y Métodos Se incluyeron 94 pacientes sin cardiopatías significativas, con adecuada factibilidad para estimar presión pulmonar sistólica (PPS) basal y en máxima carga durate el eco-estrés en ejercicio. De acuerdo al valor de presión pulmonar con el ejercicio, la población fue estratificada en dos grupos: a) PI Abstract in english Background The physiological behavior of pulmonary artery pressure during exercise has not been precisely established yet. There is lack of agreement in the published literature about the abnormal values of pulmonary artery pressure (PAP) during exercise in the absence of mitral valve disease. Indee [...] d, the last guidelines do not recommend using mean pulmonary artery pressure value ? 30 mmHg during exercise to define pulmonary hypertension. There is scarce information about the hemodynamic and functional response of the right ventricle (RV) during exercise and if it is useful to discriminate between a physiological or abnormal response of the pulmonary artery pressure. Objectives To determine the behavior of PAP during exercise and to compare the echocardiographic parameters of systolic and diastolic RV function in relation to PAP levels. Material and Methods A total of 94 patients without significant heart disease were included. Systolic pulmonary artery pressure (SPAP) at rest and maximum exercise during dobutamine stress echocardiography was adequately measured in all patients. The population was divided into two groups according to the value of pulmonary artery pressure during exercise: a) PAP

Adrián J, Lescano; Roberto G, García Eleisequi; Carlos C, Canet; Martín J, Lombardero; Roberto O, Martingano.

2011-06-01

119

Relationship of daily arterial blood pressure monitoring readings and arterial stiffness profile in male patients with chronic obstructive pulmonary disease combined with arterial hypertension  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the study was to determine correlation between arterial blood pressure daily rhythm and daily profile of arterial stiffness in male patients with chronic obstructive pulmonary disease (COPD and arterial hypertension. Materials et methods: Prospective investigation comprised 45 male patients with COPD and arterial hypertension. Individuals of 40 years younger and 80 years elder, patients with diabetes, stroke, angina pectoris, or heart infarction, vascular diseases, and exacerbation of chronic disease, bronchial and pulmonary diseases of other etiology were excluded from the analyses. Comparison group included 47 patients with essential arterial hypertension and without chronic respiratory diseases closely similar on general parameters with patients from main clinical series. Twenty-four-hour arterial blood pressure monitoring (ABPM and daily arterial stiffness monitoring were performed using BPLab® MnSDP-2 apparatus (Petr Telegin, Russian Federation. Results: Patients with COPD combined with arterial hypertension with raised arterial stiffness measures prevail over individuals in essential hypertension group. There is pathological alteration of the ABPM circadian rhythm and raised «Pressure load» values in raised arterial stiffness group. Conclusion: We found ABPM raised parameters in patients with COPD and arterial hypertension. It confirms necessity of ABPM in daily arterial stiffness assessment in patients with COPD.

Karoli N.A.

2013-06-01

120

Effects of PDE type 5 inhibitors on Left Ventricular Diastolic Dysfunction in Resistant Hypertension / Efeitos dos Inibidores da PDE do Tipo 5 sobre a Disfunção Diastólica Ventricular Esquerda na Hipertensão Arterial Resistente  

Scientific Electronic Library Online (English)

Full Text Available Resistant hypertension (RHTN) is a multifactorial disease characterized by blood pressure (BP) levels above goal (140/90 mmHg) in spite of the concurrent use of three or more antihypertensive drugs of different classes. Moreover, it is well known that RHTN subjects have high prevalence of left ventr [...] icular diastolic dysfunction (LVDD), which leads to increased risk of heart failure progression. This review gathers data from studies evaluating the effects of phosphodiesterase-5 (PDE-5) inhibitors (administration of acute sildenafil and short-term tadalafil) on diastolic function, biochemical and hemodynamic parameters in patients with RHTN. Acute study with sildenafil treatment found that inhibition of PDE-5 improved hemodynamic parameters and diastolic relaxation. In addition, short-term study with the use of tadalafil demonstrated improvement of LVDD, cGMP and BNP-32 levels, regardless of BP reduction. No endothelial function changes were observed in the studies. The findings of acute and short-term studies revealed potential therapeutic effects of IPDE-5 drugs on LVDD in RHTN patients.

Ana Paula Cabral de, Faria; Rodrigo, Modolo; Beatriz Vaz Domingues, Moreno; Heitor, Moreno.

2015-01-01

121

Effects of PDE type 5 inhibitors on Left Ventricular Diastolic Dysfunction in Resistant Hypertension / Efeitos dos Inibidores da PDE do Tipo 5 sobre a Disfunção Diastólica Ventricular Esquerda na Hipertensão Arterial Resistente  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Resistant hypertension (RHTN) is a multifactorial disease characterized by blood pressure (BP) levels above goal (140/90 mmHg) in spite of the concurrent use of three or more antihypertensive drugs of different classes. Moreover, it is well known that RHTN subjects have high prevalence of left ventr [...] icular diastolic dysfunction (LVDD), which leads to increased risk of heart failure progression. This review gathers data from studies evaluating the effects of phosphodiesterase-5 (PDE-5) inhibitors (administration of acute sildenafil and short-term tadalafil) on diastolic function, biochemical and hemodynamic parameters in patients with RHTN. Acute study with sildenafil treatment found that inhibition of PDE-5 improved hemodynamic parameters and diastolic relaxation. In addition, short-term study with the use of tadalafil demonstrated improvement of LVDD, cGMP and BNP-32 levels, regardless of BP reduction. No endothelial function changes were observed in the studies. The findings of acute and short-term studies revealed potential therapeutic effects of IPDE-5 drugs on LVDD in RHTN patients.

Ana Paula Cabral de, Faria; Rodrigo, Modolo; Beatriz Vaz Domingues, Moreno; Heitor, Moreno.

122

Influence of arterial wall compliance on the pressure drop across coronary artery stenoses under hyperemic flow condition.  

Science.gov (United States)

Hemodynamic endpoints such as flow and pressure drop are often measured during angioplasty procedures to determine the functional severity of a coronary artery stenosis. There is a lack of knowledge regarding the influence of compliance of the arterial wall-stenosis on the pressure drop under hyperemic flows across coronary lesions. This study evaluates the influence in flow and pressure drop caused by variation in arterial-stenosis compliance for a wide range of stenosis severities. The flow and pressure drop were evaluated for three different severities of stenosis and tested for limiting scenarios of compliant models. The Mooney-Rivlin model defined the non-linear material properties of the arterial wall and the plaque regions. The non-Newtonian Carreau model was used to model the blood flow viscosity. The fluid (blood)-structure (arterial wall) interaction equations were solved numerically using the finite element method. Irrespective of the stenosis severity, the compliant models produced a lower pressure drop than the rigid artery due to compliance of the plaque region. A wide variation in the pressure drop was observed between different compliant models for significant (90% area occlusion) stenosis with 41.0, 32.1, and 29.8 mmHg for the rigid artery, compliant artery with calcified plaque, and compliant artery with smooth muscle cell proliferation, respectively. When compared with the rigid artery for significant stenosis the pressure drop decreased by 27.7% and 37.6% for the calcified plaque and for the smooth muscle cell proliferation case, respectively. These significant variations in pressure drop for the higher stenosis may lead to misinterpretation and misdiagnosis of the stenosis severity. PMID:21391325

Konala, Bhaskar Chandra; Das, Ashish; Banerjee, Rupak K

2011-03-01

123

Continuous cardiac output and left atrial pressure monitoring by long time interval analysis of the pulmonary artery pressure waveform: proof of concept in dogs.  

Science.gov (United States)

We developed a technique to continuously (i.e., automatically) monitor cardiac output (CO) and left atrial pressure (LAP) by mathematical analysis of the pulmonary artery pressure (PAP) waveform. The technique is unique to the few previous related techniques in that it jointly estimates the two hemodynamic variables and analyzes the PAP waveform over time scales greater than a cardiac cycle wherein wave reflections and inertial effects cease to be major factors. First, a 6-min PAP waveform segment is analyzed so as to determine the pure exponential decay and equilibrium pressure that would eventually result if cardiac activity suddenly ceased (i.e., after the confounding wave reflections and inertial effects vanish). Then, the time constant of this exponential decay is computed and assumed to be proportional to the average pulmonary arterial resistance according to a Windkessel model, while the equilibrium pressure is regarded as average LAP. Finally, average proportional CO is determined similar to invoking Ohm's law and readily calibrated with one thermodilution measurement. To evaluate the technique, we performed experiments in five dogs in which the PAP waveform and accurate, but highly invasive, aortic flow probe CO and LAP catheter measurements were simultaneously recorded during common hemodynamic interventions. Our results showed overall calibrated CO and absolute LAP root-mean-squared errors of 15.2% and 1.7 mmHg, respectively. For comparison, the root-mean-squared error of classic end-diastolic PAP estimates of LAP was 4.7 mmHg. On future successful human testing, the technique may potentially be employed for continuous hemodynamic monitoring in critically ill patients with pulmonary artery catheters. PMID:19057003

Xu, Da; Olivier, N Bari; Mukkamala, Ramakrishna

2009-02-01

124

Correlation analysis of the changes in arterial blood pressure in people with acute mountain sickness when exposed to high altitude  

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Full Text Available Objectives ?To investigate the changes in arterial blood pressure in the healthy lowlanders when they were exposed to different altitudes and duration, and the relationship of the exposure with the prevalence and susceptibility of acute mountain sickness (AMS, in order to evaluate the significance of arterial blood pressure changes in the diagnosis of AMS and its clinical risk. Methods ?Demographic data and blood pressure parameters [systolic blood pressure (SBP, diastolic blood pressure (DBP, mean arterial BP (MABP] of healthy lowlanders (inhabitants in ?500m were collected after being exposed to 3700m on day 1, 3, 5 and 7, and also after being exposed to 4400m on day 5, while healthy young men living at low altitude were randomly selected as the control group. Simultaneously the AMS symptoms Questionnaire was filled. The Lake Louise acute mountain sickness scoring system (LLS was used to diagnose AMS. The changes in arterial blood pressure in people above and its correlation with AMS were analyzed. Results ?After acute exposure to 3700m (day 1, SBP, DBP and MABP rose obviously, and then descended moderately after adaptation for about a week, but still higher than that of LA level (P<0.05. And then SBP, DBP and MABP rose again at high-altitude of 4400m, but lower than the levels of day 1 at 3700m. MABP at 3700m and 4400m were related to LLS (r=0.138, P=0.048; r=0.145, P=0.045, respectively. MABP levels for diagnosis of AMS at 3700m showed an cut-off point of 98.5mmHg with sensitivity of 32.8% and specificity of 73.7% (P<0.05, and MABP levels for diagnosis of AMS at 4400m showed an cut-off point of 97.8mmHg with sensitivity of 42.4% and specificity of 75.5% (P<0.05. Conclusions ?After exposure to acute hypoxia, MABP may serve as a predictive parameter for diagnosis of AMS. However, the clinical application of MABP as a diagnostic criterion is limited because of its poor specificity or sensitivity. The use of MABP as a diagnostic criterion should be combined with other indicators such as arterial blood oxygen saturation (SaO2 for the diagnosis of AMS. DOI: 10.11855/j.issn.0577-7402.2014.03.12

Yang LIU

2014-03-01

125

Dynamic Stress Analysis of the Arterial Wall Utilizing Physiological Pressure Waveforms  

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Full Text Available Arterial diseases, promoted by alterations in arterial wall properties, are among the main causes of mortality. Mechanical stresses of the arterial wall caused by pulsatile luminal pressure define arterial function in normal and pathological conditions. This study aims to determine dynamic stress distribution in the arterial wall subjected to physiological pressure waveforms. Finite element models of a typical artery are developed to evaluate Von Misses stress in the arterial wall due to physiological pressure waveforms and with differing mechanical properties. Mechanical parameters include Young's modulus of elasticity, non-linear stress-strain relationship and visco-elastic parameter. The appropriate boundary conditions are allocated to allow radial expansion. Application of physiological pulsatile pressure results in stress waves with the values and waveforms markedly influenced by mechanical properties of the arterial wall and blood pressure pulse. Elevated elastic modulus of the arterial wall results in significant increase in maximum stress. Viscoelastic property leads to reduction of the peak stress and smoothening of the stress waveform. The pressure waveform is also a major parameter affecting the stress pattern in arterial wall. Hypertensive arteries result in higher and sharper stress waves not only because of a higher systolic value but also because of the sharper waveform. The combination of these parameters produces the resultant stress pattern in the arterial wall.

M. M. Khani

2008-01-01

126

Efeito do treinamento com pesos na pressão arterial de repouso em idosas normotensas / Effect of resistence training in blood pressure at rest in normotensive elderly  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese INTRODUÇÃO: O treinamento com pesos (TP) tem sido amplamente empregado em adultos idosos com objetivo de minimizar ou reverter os efeitos deletérios do processo de envelhecimento no sistema neuromuscular. No entanto, os potenciais benefícios do TP para a pressão arterial e frequência cardíaca de rep [...] ouso de adultos idosos ainda permanecem controversos. OBJETIVO: Analisar o efeito de oito semanas de TP na pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), pressão arterial média (PAM) e frequência cardíaca (FC) de repouso em idosas sem hipertensão arterial. MÉTODOS: Dezessete mulheres idosas (66,0 ± 5,8 anos) sem experiência em TP foram separadas aleatoriamente em grupo treinamento (GT; n = 10) e grupo controle (GC; n = 7). As variáveis hemodinâmicas de repouso foram avaliadas pelo método auscultatório (esfigmomanômetro de mercúrio) e frequencímetro cardíaco (Polar), antes e após oito semanas do período experimental. RESULTADOS: Reduções atribuíveis ao TP foram encontradas apenas para a PAS (-13,4 mmHg; p Abstract in english INTRODUCTION: Resistance training (RT) has been widely used for older adults in order to minimize or reverse the deleterious effects of aging in the neuromuscular system. However, the potential benefits of RT on arterial blood pressure and heart rate at rest in older adults remain controversial. OBJ [...] ECTIVE: To analyze the effect of eight weeks of RT on systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) in older women without hypertension. METHODS: Seventeen women (aged 66.0 ± 5.8 years) without previous experience in RT were randomly assigned to either a training (TG, n = 10) or control (CG, n = 7) groups. Hemodynamic parameters at rest were evaluated by auscultatory method (mercury sphygmomanometer) and HR monitor (Polar), before and after eight weeks of experimental period. RESULTS: Reductions attributable to RT were found only to SBP (-13.4 mmHg, p

André Luiz Demantova, Gurjão; Raquel, Gonçalves; Nelson Hilário, Carneiro; Marilia, Ceccato; José Claudio, Jambassi Filho; Sebastião, Gobbi.

2013-06-01

127

Cerebral autoregulation with changes in arterial and cerebral venous pressure  

International Nuclear Information System (INIS)

The effect of cerebral venous pressure (Pcv) elevation on cerebral autoregulation has been incompletely studied. The authors compared the effect of decreased cerebral perfusion pressure (CPP) by elevated Pcv and decreased arterial pressure (Pa) on cerebral blood flow (CBF) in a canine modified bypass model. CPP of 80, 70, 60, 50, 40 and 30 mmHg were produced by decreasing Pa with intracranial pressure (ICP) and Pcv maintained at 0 mmHg (group 1, n = 5), or by elevating Pcv as Pa was maintained at 80 mmHg (group 2, n = 5. CBF was measured using radiolabeled microspheres, and CMRO2 = CBF times arterial-sagittal sinus O2 content difference. Cerebrovascular resistance (CVR) = CPP/CBF. In group 1 CBF (ml/100 gm/min) was unchanged from control (36 +/- 4) as CPP was decreased from 80 to 40 mmHg. As CPP was decreased to 30 mmHg, CBF decreased to 28 +/- 1. CVR (mmHg/ml/min/100 gm) was 2.3 +/- 0.3 and progressively decreased to 1.0 +/- 0.1 at CPP of 30 mmHg. In group 2 CBF was 34 +/- 3 and was unchanged as CPP decreased to 50 mmHg. At CPP of 40 and 30 mmHg CBF decreased to 25 +/- 3 and 22 +/- 2 respectively. Control CRV was 2.4 +/- 0.2 and progressively decreased to 1.4 +/- 0.1 as CPP decreased to 30 mmHg. CMRO2 was unchanged from control in both groups. Thus, CBF is maintained to low CPP regardless of whether vascular transmural pressure was decreased (decrease Pa) or increased (increased Pcv) demonstrating that the myogenic mechanism of autoregulation may be unimportant in normoxic dogs

128

Regulation of optic nerve head blood flow during combined changes in intraocular pressure and arterial blood pressure  

OpenAIRE

In the choroid, there is evidence that blood flow does not only depend on ocular perfusion pressure (OPP), but also on absolute mean arterial pressure (MAP) and intraocular pressure (IOP). The present study included 40 healthy subjects to investigate whether such behavior is also found in the optic nerve head (ONH). The ONH blood flow (ONHBF) was studied using laser Doppler flowmetry during a separate increase in IOP and MAP as well as during a combined elevation. Mean arterial pressure was i...

Boltz, Agnes; Schmidl, Doreen; Werkmeister, Rene? M.; Lasta, Michael; Kaya, Semira; Palkovits, Stefan; Told, Reinhard; Napora, Katarzyna J.; Popa-cherecheanu, Alina; Garho?fer, Gerhard; Schmetterer, Leopold

2013-01-01

129

Machine Learning Techniques for Arterial Pressure Waveform Analysis  

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Full Text Available The Arterial Pressure Waveform (APW can provide essential information about arterial wall integrity and arterial stiffness. Most of APW analysis frameworks individually process each hemodynamic parameter and do not evaluate inter-dependencies in the overall pulse morphology. The key contribution of this work is the use of machine learning algorithms to deal with vectorized features extracted from APW. With this purpose, we follow a five-step evaluation methodology: (1 a custom-designed, non-invasive, electromechanical device was used in the data collection from 50 subjects; (2 the acquired position and amplitude of onset, Systolic Peak (SP, Point of Inflection (Pi and Dicrotic Wave (DW were used for the computation of some morphological attributes; (3 pre-processing work on the datasets was performed in order to reduce the number of input features and increase the model accuracy by selecting the most relevant ones; (4 classification of the dataset was carried out using four different machine learning algorithms: Random Forest, BayesNet (probabilistic, J48 (decision tree and RIPPER (rule-based induction; and (5 we evaluate the trained models, using the majority-voting system, comparatively to the respective calculated Augmentation Index (AIx. Classification algorithms have been proved to be efficient, in particular Random Forest has shown good accuracy (96.95% and high area under the curve (AUC of a Receiver Operating Characteristic (ROC curve (0.961. Finally, during validation tests, a correlation between high risk labels, retrieved from the multi-parametric approach, and positive AIx values was verified. This approach gives allowance for designing new hemodynamic morphology vectors and techniques for multiple APW analysis, thus improving the arterial pulse understanding, especially when compared to traditional single-parameter analysis, where the failure in one parameter measurement component, such as Pi, can jeopardize the whole evaluation.

João Cardoso

2013-05-01

130

Machine learning techniques for arterial pressure waveform analysis.  

Science.gov (United States)

The Arterial Pressure Waveform (APW) can provide essential information about arterial wall integrity and arterial stiffness. Most of APW analysis frameworks individually process each hemodynamic parameter and do not evaluate inter-dependencies in the overall pulse morphology. The key contribution of this work is the use of machine learning algorithms to deal with vectorized features extracted from APW. With this purpose, we follow a five-step evaluation methodology: (1) a custom-designed, non-invasive, electromechanical device was used in the data collection from 50 subjects; (2) the acquired position and amplitude of onset, Systolic Peak (SP), Point of Inflection (Pi) and Dicrotic Wave (DW) were used for the computation of some morphological attributes; (3) pre-processing work on the datasets was performed in order to reduce the number of input features and increase the model accuracy by selecting the most relevant ones; (4) classification of the dataset was carried out using four different machine learning algorithms: Random Forest, BayesNet (probabilistic), J48 (decision tree) and RIPPER (rule-based induction); and (5) we evaluate the trained models, using the majority-voting system, comparatively to the respective calculated Augmentation Index (AIx). Classification algorithms have been proved to be efficient, in particular Random Forest has shown good accuracy (96.95%) and high area under the curve (AUC) of a Receiver Operating Characteristic (ROC) curve (0.961). Finally, during validation tests, a correlation between high risk labels, retrieved from the multi-parametric approach, and positive AIx values was verified. This approach gives allowance for designing new hemodynamic morphology vectors and techniques for multiple APW analysis, thus improving the arterial pulse understanding, especially when compared to traditional single-parameter analysis, where the failure in one parameter measurement component, such as Pi, can jeopardize the whole evaluation. PMID:25562520

Almeida, Vânia G; Vieira, João; Santos, Pedro; Pereira, Tânia; Pereira, H Catarina; Correia, Carlos; Pego, Mariano; Cardoso, João

2013-01-01

131

Adolescencia e hipertensión arterial / Adolescence and high blood pressure  

Scientific Electronic Library Online (English)

Full Text Available Introducción: se desconocen las características demográficas y clínicas de la hipertensión arterial en niños y adolescentes en Guane. Objetivo: caracterizar la hipertensión arterial en adolescentes de 10-15 años en Guane en el año 2013. Material y método: se realizó una investigación observacional, [...] descriptiva, transversal, con componente analítico en 360 niños de las edades mencionadas, en los que se comprobó: tensión arterial, índice de masa corporal, circunferencia de la cintura, tabaquismo y actividad física, todos con referencia a la edad y al sexo. Se resumieron las variables cualitativas en frecuencias absolutas y relativas porcentuales, y la asociación entre las mismas se midió mediante las pruebas de X² y Odds Ratio al 95 % de certeza. Resultados: hubo 175 normotensos en las edades 10-12 años, 8 pre-hipertensos y 9 hipertensos en el grupo de 13-15 años. Hubo prevalencia estadísticamente significativa (x²) de normotensos en el sexo femenino (p = 0.008). La obesidad estaba incrementada más de 5 veces en los varones (p = 0,002) y en edades de 13-15 años. Existió un incremento significativo de hipertensos en el grupo de 13-15 años con aumento de la circunferencia abdominal (p Abstract in english Introduction: the demographic and clinical characteristics of high blood pressure in Guane children and adolescents are unknown. Objective: to characterize high blood pressure in Guane 10-15-year-old adolescents, 2013. Material and method: an observational, descriptive, cross-sectional research was [...] carried out, with an analytical component, on 360 children of the mentioned ages, in which we analyzed: blood pressure, body mass index, waist circumference, smoking and physical activity, all of which with reference to age and sex. The quantitative variants were defined in percentage absolute and relative frequencies, while association among them was measured by chi-square and Odds Ratio tests at 95% of certitude. Results: there were 175 with normal blood pressure between 10-12 years old, 8 pre-hypertensives aged 13-15 years old. There was a statistically significant prevalence of female patients with normal blood pressure (p=0.008). Obesity increased five times in male patients (p=0.002) and in ages 13-15 years old. There was a significant increase in hypertensive patients aged 13-15 years old, with increase in the waist circumference (p

Gabriela Elizabeth, Galarza Carrión.

2014-10-01

132

Left ventricular diastolic dysfunction and N-terminal probrain sodium-uretic peptid level in patients with atrial fibrillation  

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Full Text Available In our study 100 consecutive non-valvular permanent atrial fibrillation patients with NYHA I – III heart failure, 43 - 86 years old (65 men and 35 women were examined. Control group consisted of 30 patients with arterial hypertension and coronary artery disease matched by age, sex with basic group. Relationship of NT-proBNP with echocardiographic parameters of left heart were studied. Transthoracic echocardiography with tissue doppler measurements were performed on echocardiograph “SONOS 7500”. For left ventricular filling pressure assessment ratio Em/Ea was used due to its diagnostic value in atrial fibrillation (regardless of left ventricular ejection fraction. Mean left ventricular filling pressure was increased in patients with heart failure: in atrial fibrillation group and controls as well. In comparison with controls atrial fibrillation group was more likely to have higher both systolic and diastolic left atrial square and volume. According to Em/Ea in 95% of patients with non-valvular atrial fibrillation high left ventricular filling pressure was observed, this testifies to diastolic dysfunction. This parameter correlated well with left atrial square and volume during systole and diastole. Correlation between NT pro-BNP level and NYHA class of heart failure, left ventricular filling pressure was determined in patients with atrial fibrillation. Tissue doppler echocardiography makes it possible to diagnose left ventricular diastolic dysfunction in atrial fibrillation patients.

Dzyak G.V.

2013-06-01

133

HIF isoforms in the skin differentially regulate systemic arterial pressure.  

Science.gov (United States)

Vascular flow through tissues is regulated via a number of homeostatic mechanisms. Localized control of tissue blood flow, or autoregulation, is a key factor in regulating tissue perfusion and oxygenation. We show here that the net balance between two hypoxia-inducible factor (HIF) transcription factor isoforms, HIF-1? and HIF-2?, is an essential mechanism regulating both local and systemic blood flow in the skin of mice. We also show that balance of HIF isoforms in keratinocyte-specific mutant mice affects thermal adaptation, exercise capacity, and systemic arterial pressure. The two primary HIF isoforms achieve these effects in opposing ways that are associated with HIF isoform regulation of nitric oxide production. We also show that a correlation exists between altered levels of HIF isoforms in the skin and the degree of idiopathic hypertension in human subjects. Thus, the balance between HIF-1? and HIF-2? expression in keratinocytes is a control element of both tissue perfusion and systemic arterial pressure, with potential implications in human hypertension. PMID:24101470

Cowburn, Andrew S; Takeda, Norihiko; Boutin, Adam T; Kim, Jung-Whan; Sterling, Jane C; Nakasaki, Manando; Southwood, Mark; Goldrath, Ananda W; Jamora, Colin; Nizet, Victor; Chilvers, Edwin R; Johnson, Randall S

2013-10-22

134

Non-invasive assessment of arterial stiffness using oscillometric blood pressure measurement  

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Full Text Available Abstract Background Arterial stiffness is a major contributor to cardiovascular diseases. Because current methods of measuring arterial stiffness are technically demanding, the purpose of this study was to develop a simple method of evaluating arterial stiffness using oscillometric blood pressure measurement. Methods Blood pressure was conventionally measured in the left upper arm of 173 individuals using an inflatable cuff. Using the time series of occlusive cuff pressure and the amplitudes of pulse oscillations, we calculated local slopes of the curve between the decreasing cuff pressure and corresponding arterial volume. Whole pressure-volume curve was derived from numerical integration of the local slopes. The curve was fitted using an equation and we identified a numerical coefficient of the equation as an index of arterial stiffness (Arterial Pressure-volume Index, API. We also measured brachial-ankle (baPWV PWV and carotid-femoral (cfPWV PWV using a vascular testing device and compared the values with API. Furthermore, we assessed carotid arterial compliance using ultrasound images to compare with API. Results The slope of the calculated pressure-volume curve was steeper for compliant (low baPWV or cfPWV than stiff (high baPWV or cfPWV arteries. API was related to baPWV (r = -0.53, P r = -0.49, P r = 0.32, P Conclusions These results suggest that our method can simply and simultaneously evaluate arterial stiffness and blood pressure based on oscillometric measurements of blood pressure.

Komine Hidehiko

2012-02-01

135

[Perioperative care of patients with diastolic heart failure. Interface to anesthesia].  

Science.gov (United States)

Diastolic heart failure leads to an increase in perioperative morbidity and mortality. The prevalence of this disease is rising and multiple risk factors have already been identified. Besides higher age and female gender, arterial hypertension, diabetes mellitus and coronary artery disease in particular have to be considered. Clinical examination and laboratory analyses are important for preoperative evaluation; however, echocardiography plays the most important role in the diagnostics of diastolic heart failure. The transmitral flow profile can be used to differentiate the grades of diastolic dysfunction using the ratio between early passive ventricular filling (E) and late active filling due to atrial contraction (A). Data concerning the ideal anesthesia technique are for the most part lacking; however, the application of thoracic epidural anesthesia seems to be beneficial. A great deal of attention has to be paid to the intraoperative volume status of patients with diastolic dysfunction as hypovolemia and hypervolemia can both have detrimental effects. Arrhythmias and major changes in blood pressure put this special group of patients at additional risks. PMID:25501914

Heschl, S; Colantonio, C; Pieske, B; Toller, W

2014-12-01

136

Obesidad e hipertensión arterial: señales ateroscleróticas tempranas en los escolares Obesity and high blood pressure: early atherosclerosis signs  

Directory of Open Access Journals (Sweden)

Full Text Available INTRODUCCIÓN. La hipertensión arterial y la obesidad son dos importantes factores de riesgo, muy relacionados con la aterosclerosis. Su detección desde edades tempranas permite prevenir o modificar favorablemente el desarrollo de esta enfermedad en la adultez. El objetivo de este trabajo fue identificar la presencia de obesidad e hipertensión en escolares de 3 escuelas primarias. MÉTODOS. Se realizó un estudio observacional y analítico de tipo transversal en 3 escuelas primarias del municipio Plaza de la Revolución en Ciudad de La Habana, que incluyó a 986 niños de 5 a 12 años de edad. Se utilizaron estadísticas descriptivas (medias y desviación estándar, la prueba de la t de Student y ji al cuadrado, y se consideró significativo un valor de p INTRODUCTION. The obesity and the high blood pressure are two important risk factor very related to atherosclerosis. Its detection from early ages allows to prevent or to modify favourably the development of this disease in adulthood. The aim of present paper was to identify the presence of obesity and high blood pressure in pupils from three primary schools. METHODS. A observational, analytical and cross-sectional study was conducted in three primary schools from the Plaza de la Revolución municipality in Ciudad de La Habana including 986 children aged from 5 to 12. Descriptive statistics were used (means and standard deviation, Student t test and Chi² test taking into account as significant a value of p<0,05. RESULTS. From the 482 males pupils 79 were obeses (16,3% and 58 (12% had a excess weight; from the total of girls pupils, 86 (17,6% were obeses and 63 (12,9% had excess weight. Regarding the study pupils, these figures represent a 17% of obesity and a 12,5% of excess weight. Analyzing the arterial pressure it was possible to note that from the 58 hypertensive pupils there were 23 males (40% and 35 girls (60%. Among the 66 pre-hypertensives 31 were males (47% and 35 (53% were girls. The total of hypertensives ones represented a 6% of all the pupils and the pre-hypertensives ones constituted the 6,8%. There was also a greater frequency in girls. Means of systolic and diastolic arterial tension were present in malnourished children, those with excess weight and the obeses ones in relation to those thins and those with a normal weight. CONCLUSIONS. Relating the nutritional assessment to classification of arterial pressure it was noted that the nutritional status of to be malnourished, to have excess weight and to be obese influenced significantly in the rise of the arterial tension (p ? 0,001.

Marlene Ferrer Arrocha

2010-12-01

137

Correlation between antrhopometric indicators and blood pressure in adolescents / Correlação entre indicadores antropométricos e pressão arterial de adolescentes / Correlación entre los indicadores antropométricos y presión arterial de los adolescentes  

Scientific Electronic Library Online (English)

Full Text Available O objetivo deste estudo foi analisar a correlação entre indicadores antropométricos e pressão arterial de adolescentes de Imperatriz-MA. Trata-se de estudo quantitativo do tipo transversal, desenvolvido entre setembro e novembro de 2012 com 218 estudantes. O questionário utilizado contemplou dados d [...] e identificação, antropométricos e pressão arterial sistólica e diastólica. Quanto aos valores de pressão arterial, verificou-se que 4,6%, 2,4% e 1,3% da amostra estavam inseridos na categoria limítrofe, hipertensão em estágio I e II, respectivamente. Entre o sexo feminino, o índice de adiposidade central e todas as pregas cutâneas apresentaram valores médios superiores ao masculino e, ainda, constatou-se correlação positiva entre pressão arterial sistólica e altura (r=0,18), peso (r=0,20) e circunferência da cintura (r=0,17); negativa entre pressão arterial diastólica e índice de adiposidade central (r=-0,18). A medida da circunferência do pescoço e da cintura foi a única medida antropométrica com correlação positiva e simultânea com pressão arterial sistólica em ambos os sexos. Abstract in spanish El objetivo de este estudio fue analizar la correlación entre la presión antropométrico y sangre de los adolescentes de Imperatriz-MA. Se trata de un estudio transversal, realizado entre septiembre y noviembre de 2012 con 218 estudiantes. El cuestionario incluía datos de identificación, antropométri [...] cas y de presión arterial sistólica y diastólica. En el análisis de las pruebas de correlación de Pearson y de Spearman utilizado bajo criterios preestablecidos. Sólo el 8,3% de la muestra tenía cifras de presión arterial fuera del rango normal, siendo un 4,6%, 2,4% y 1,3% en el límite de la categoría hipertensión en estadio I y II, respectivamente. En las mujeres la tasa de obesidad central y pliegues cutáneos mostraron los mayores valores medios que los hombres. En las niñas hay una correlación positiva entre la presión arterial sistólica y la altura (r=0,18), el peso (r=0,20) y la circunferencia de la cintura (r=0,17); correlación negativa entre la presión arterial diastólica y el índice de adiposidad central (r=-0,18). Una sola medida antropométrica que se correlaciona positivamente con la presión arterial sistólica y simultánea en ambos sexos es la medida de la circunferencia del cuello y la cintura. Abstract in english The objective of the present study was to analyze the correlation between anthropometric indicators and blood pressure of adolescents from Imperatriz, state of Maranhão, Brazil. It is a quantitative cross-sectional study, developed between September and November of 2012 with 218 students. We used a [...] questionnaire to collect data regarding identification, anthropometrics, and systolic and diastolic blood pressure. Considering blood pressure, we found that 4.6%, 2.4% and 1.3% of the sample were included in the borderline, stage 1 and stage 2 hypertension categories, respectively. Among female participants, body adiposity index and skinfold presented higher mean values than those of their male counterparts. Furthermore, we observed a positive correlation between systolic blood pressure and height (r=0.18), weight (r=0.20) and waist circumference (r=0.17), and a negative correlation between diastolic blood pressure and body adiposity index (r=-0.18). The measures of neck and waist circumference were the only anthropometric measures with positive and simultaneous correlations with systolic blood pressure for both genders.

Aline Viana de, Oliveira; Ana Cristina Pereira de Jesus, Costa; Lívia Maia, Pascoal; Leonardo Hunaldo dos, Santos; Emilia Soares, Chaves; Márcio Flávio Moura de, Araújo.

2014-12-01

138

Blood pressure changes in dogs with babesiosis  

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Full Text Available Systemic arterial blood pressures were measured in 30 dogs with acute babesiosis, 10 each with mild uncomplicated, severe uncomplicated and complicated disease. Ten healthy dogs were used as controls. Hypotension was defined as more than 3 standard deviations below the control mean. Normal mean pressures (±SD were: systolic arterial pressure 151 (±11 mm Hg, diastolic arterial pressure 89 (±8 mm Hg and mean arterial pressure 107 (±10 mmHg. Hypotension was the most frequent abnormality, and increased strikingly in incidence as disease severity increased, with 5/10 dogs in the complicated group being hypotensive for systolic, diastolic and mean arterial pressures, compared with 2/10 in the severe uncomplicated group and 0/10 in the mild uncomplicated group. Systolic, diastolic and mean arterial pressures in the complicated group and severe uncomplicated group, and systolic pressure in the mild uncomplicated group, were significantly lower than in the controls. There were no significant relationships between arterial pressures and age, pulse rate, respiratory rate, temperature, mucous membrane colour or haematocrit. There was a significant negative correlation between arterial pressures and white cell and immature neutrophil counts. Arterial pressures differed significantly between dogs that were clinically collapsed and those that were not, but not between survivors and non-survivors. Pulse pressure (systolic - diastolic was low in 7/10 complicated, 1/10 mild uncomplicated, and 1/10 severe uncomplicated cases, and differed significantly between the complicated and control groups. The high incidence of hypotension in clinically severe babesiosis has important implications for therapy.

L.S. Jacobson

2012-07-01

139

Perfusion of veins at arterial pressure increases the expression of KLF5 and cell cycle genes in smooth muscle cells  

International Nuclear Information System (INIS)

Vascular smooth muscle cell (VSMC) proliferation remains a major cause of veno-arterial graft failure. We hypothesised that exposure of venous SMCs to arterial pressure would increase KLF5 expression and that of cell cycle genes. Porcine jugular veins were perfused at arterial or venous pressure in the absence of growth factors. The KLF5, c-myc, cyclin-D and cyclin-E expression were elevated within 24 h of perfusion at arterial pressure but not at venous pressure. Arterial pressure also reduced the decline in SM-myosin heavy chain expression. These data suggest a role for KLF5 in initiating venous SMCs proliferation in response to arterial pressure.

140

Diastolic dysfunction and diastolic heart failure: diagnostic, prognostic and therapeutic aspects  

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Full Text Available Abstract Left ventricular (LV diastolic dysfunction (DD and diastolic heart failure (HF, that is symptomatic DD, are due to alterations of myocardial diastolic properties. These alterations involve relaxation and/or filling and/or distensibility. Arterial hypertension associated to LV concentric remodelling is the main determinant of DD but several other cardiac diseases, including myocardial ischemia, and extra-cardiac pathologies involving the heart are other possible causes. In the majority of the studies, isolated diastolic HF has been made equal to HF with preserved systolic function (= normal ejection fraction but the true definition of this condition needs a quantitative estimation of LV diastolic properties. According to the position of the European Society of Cardiology and subsequent research refinements the use of Doppler echocardiography (transmitral inflow and pulmonary venous flow and the new ultrasound tools has to be encouraged for diagnosis of DD. In relation to uncertain definitions, both prevalence and prognosis of diastolic heart failure are very variable. Despite an apparent lower death rate in comparison with LV systolic HF, long-term follow-up (more than 5 years show similar mortality between the two kinds of HF. Recent studies performed by Doppler diastolic indexes have identified the prognostic power of both transmitral E/A ratio 1.5 (restrictive patterns. The therapy of LV DD and HF is not well established but ACE-inhibitors, angiotensin inhibitors, aldosterone antagonists and ?-blockers show potential beneficial effect on diastolic properties. Several trials, completed or ongoing, have been planned to treat DD and diastolic HF.

Galderisi Maurizio

2005-04-01

141

Stiffness Indices and Fractal Dimension relationship in Arterial Pressure and Diameter Time Series in-Vitro  

International Nuclear Information System (INIS)

The advent of vascular diseases, such as hypertension and atherosclerosis, is associated to significant alterations in the physical properties of arterial vessels. Evaluation of arterial biomechanical behaviour is related to the assessment of three representative indices: arterial compliance, arterial distensibility and arterial stiffness index. Elasticity is the most important mechanical property of the arterial wall, whose natures is strictly non-linear. Intervention of elastin and collagen fibres, passive constituent elements of the arterial wall, is related to the applied wall stress level. Concerning this, appropriate tools are required to analyse the temporal dynamics of the signals involved, in order to characterize the whole phenomenon. Fractal geometry can be mentioned as one of those techniques. The aim of this study consisted on arterial pressure and diameter signals processing, by means of nonlinear techniques based on fractal geometry. Time series morphology was related to different arterial stiffness states, generated by means of blood flow variations, during experiences performed in vitro.

142

Intraspecific scaling of arterial blood pressure in the Burmese python.  

Science.gov (United States)

Interspecific allometric analyses indicate that mean arterial blood pressure (MAP) increases with body mass of snakes and mammals. In snakes, MAP increases in proportion to the increased distance between the heart and the head, when the heart-head vertical distance is expressed as ?gh (where ? is the density of blood, G: is acceleration due to gravity and h is the vertical distance above the heart), and the rise in MAP is associated with a larger heart to normalize wall stress in the ventricular wall. Based on measurements of MAP in Burmese pythons ranging from 0.9 to 3.7 m in length (0.20-27 kg), we demonstrate that although MAP increases with body mass, the rise in MAP is merely half of that predicted by heart-head distance. Scaling relationships within individual species, therefore, may not be accurately predicted by existing interspecific analyses. PMID:24737752

Enok, Sanne; Slay, Christopher; Abe, Augusto S; Hicks, James W; Wang, Tobias

2014-07-01

143

An Inexpensive Arterial Pressure Wave Sensor and its application in different physiological condition  

OpenAIRE

Arterial Blood Pressure wave monitoring is considered to be important in assessment of cardiovascular system. We developed a novel pulse wave detection system using low frequency specific piezoelectric material as pressure wave sensor. The transducer detects the periodic change in the arterial wall diameter produced by pressure wave and the amplified signal after integration represents the pressure wave. The signal before integration is proportional to the rate of change of ...

Sur, Shantanu; Ghatak, S. K.

2005-01-01

144

SPIRAL ARTERIAL REMODELING IS NOT ESSENTIAL FOR NORMAL BLOOD PRESSURE REGULATION IN PREGNANT MICE  

OpenAIRE

Maternal cardiovascular adaptations occur in normal pregnancy, systemically and within the uterus. In humans, gestational control of blood pressure is clinically important. Transient structural remodeling of endometrial spiral arteries normally occurs in human and mouse pregnancies. In mice, this is dependent on uterine Natural Killer cell function. Using normal and immune deficient mice, we asked whether spiral artery remodeling critically regulates gestational mean arterial pressure and/or ...

Burke, Suzanne D.; Barrette, Vale?rie F.; Bianco, Juares; Thorne, Julie G.; Yamada, Aureo T.; Pang, Stephen C.; Adams, Michael A.; Croy, B. Anne

2010-01-01

145

A proposed cybernetic program for the study of renin-dependent arterial pressure.  

Science.gov (United States)

The mathematical definition of arterial pressure is an essential requisite if one is to develop an informatic model. By applying analytical calculus we can set up a cybernetic model. We have proposed a cybernetic program for the study of renin-dependent arterial pressure. PMID:1828197

Gavelli, M S

1991-03-15

146

Blood pressure and associated cardiovascular risk factors in adolescents of Mexico City / Tensión arterial y su asociación con factores de riesgo cardiovascular en adolescentes de México, D.F.  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish Objetivo: Determinar la prevalencia de tensión arterial elevada y su asociación con factores de riesgo cardiovascular en adolescentes mexicanos. Métodos: Se realizó un estudio transversal en 770 hombres y 1,076 mujeres (12 a 16 años de edad) de ocho escuelas secundarias seleccionadas aleatoriamente [...] de la Ciudad de México. Se determinaron las medidas antropométricas, la tensión arterial, los lípidos y las lipoproteínas. Resultados: Las mediciones de tensión arterial fueron ajustadas por edad, género y estatura. La tasa de prevalencia de hipertensión (tensión arterial sistólica y/o la tensión arterial diastólica > a la percentila 95) y la prevalencia de pre-hipertensión (tensión arterial sistólica y diastólica > percentila 90 y Abstract in english Objective: To determine the prevalence of high blood pressure and associated cardiovascular risk factors in Mexican adolescents. Methods: A cross-sectional study was conducted in 770 male and 1076 female students (12 to 16 years old) from eight randomly selected high schools in Mexico City. Anthropo [...] metry, blood pressure and fasting lipids and lipoproteins were measured. Results: Blood pressure levels were adjusted for age, gender, and height. The prevalence rates of hypertension (systolic blood pressure (SBP) and/or diastolic (DBP) > 95th percentile), and pre-hypertension (SBP or DBP > 90th but

Juan Gabriel, Juárez-Rojas; Guillermo C, Cardoso-Saldaña; Rosalinda, Posadas-Sánchez; Aída Xóchitl, Medina-Urrutia; Liria, Yamamoto-Kimura; Carlos, Posadas-Romero.

2008-12-01

147

Effect of iohexol and diatrizoate on pulmonary arterial pressure following pulmonary angiography  

International Nuclear Information System (INIS)

A clinical comparison of the effects on pulmonary arterial pressure produced by iohexol and diatrizoate, following selective pulmonary angiography, was made in 17 patients with a normal pressure before the injection of the contrast medium. A double blind crossover study was performed and each contrast medium was administered in random order. The pulmonary arterial pressure was continuously recorded before, during and after the injection for 3 minutes. The effect of iohexol on the pulmonary arterial pressure was significantly less than that of diatrizoate. The results indicated that iohexol should be better tolerated than diatrizoate and therefore a safer contrast medium for selective pulmonary angiography. (orig.)

148

Blood pressure and arterial stiffness in obese children and adolescents.  

Science.gov (United States)

Obesity, elevated blood pressure (BP) and arterial stiffness are risk factors for cardiovascular disease. A strong relationship exists between obesity and elevated BP in both children and adults. Obesity and elevated BP in childhood track into adult life increasing the risk of cardiovascular disease in adulthood. Ambulatory BP is the most precise measure to evaluate the BP burden, whereas carotid-femoral pulse wave velocity (cfPWV) is regarded as the gold standard for evaluating arterial (i.e. aortic) stiffness. These measures might contribute to a better understanding of obesity's adverse impact on the cardiovascular system, and ultimately a better prevention and treatment of childhood obesity. The overall aim of the present PhD thesis is to investigate arterial stiffness and 24-hour BP in obese children and adolescents, and evaluate whether these measures are influenced by weight reduction. The present PhD thesis is based on four scientific papers.  In a cross-sectional design, 104 severe obese children and adolescents with an age of 10-18 years were recruited when newly referred to the Children's Obesity Clinic, Holbæk University Hospital, and compared to 50 normal weighted age and gender matched control individuals. Ambulatory BP was measured, and cfPWV was investigated in two ways in respect to the distance measure of aorta; the previously recommended length - the so called subtracted distance, and the currently recommended length - the direct distance. In a longitudinal design, the obese patients were re-investigated after one-year of lifestyle intervention at the Children's Obesity Clinic in purpose of reducing the degree of obesity. In the cross-sectional design, the obese group had higher measures of obesity, while matched for age, gender and height, when compared to the control group. In the longitudinal design, 74% of the 72 followed up obese patients experienced a significant weight reduction. CfPWV was dependent on the method used to measure the length of the aorta. The subtracted distance was not consistent in its relation to height in the obese and the control group. Opposite, the direct distance was consistent in its relation to height in the two groups. Therefore, cfPWV using the direct distance (cfPWV-direct) was regarded as the appropriate measure of arterial stiffness. CfPWV-direct was reduced in the obese group after adjustment for known confounders. In the longitudinal design, weight reduction across one year did not have an impact on cfPWV-direct in the obese patients. In fact, cfPWV-direct was higher at follow-up, which was explained by the increased age and partly by changes in BP and heart rate. The obese group had a relatively higher night- than day-time BP when compared to the control group. The obesity-related elevated night-time BP was independent of arterial stiffness and insulin resistance. Although night-time systolic BP was related to arterial stiffness and tended to be related to insulin resistance, insulin resistance and arterial stiffness were not related. In the longitudinal design, changes in anthropometric obesity measures across one year were associated with changes in 24-hour, day- and night-time BP, and consistent when evaluated in standardised values that accounted for growth. No association was found between changes in anthropometric obesity measures and changes in clinic BP. In conclusion, the results suggest that obesity in children is not "yet" associated with structural changes in aorta when evaluated with the appropriate new method of cfPWV. In this respect, weight reduction did not have an impact on arterial stiffness. The ambulatory BP, namely the night-time BP, was elevated in the obese patients, whereas changes in anthropometric obesity measures were related to changes in ambulatory BP but not to changes in clinic BP. In perspective, it is reassuring that weight changes are accompanied with a change in 24-hour BP as ambulatory BP is the most precise measure to evaluate the BP burden, and it emphasises the use of 24-hour ambulatory BP measurements in childr

Hvidt, Kristian Nebelin

2015-03-01

149

Critical buckling pressure in mouse carotid arteries with altered elastic fibers.  

Science.gov (United States)

Arteries can buckle axially under applied critical buckling pressure due to a mechanical instability. Buckling can cause arterial tortuosity leading to flow irregularities and stroke. Genetic mutations in elastic fiber proteins are associated with arterial tortuosity in humans and mice, and may be the result of alterations in critical buckling pressure. Hence, the objective of this study is to investigate how genetic defects in elastic fibers affect buckling pressure. We use mouse models of human disease with reduced amounts of elastin (Eln+/-) and with defects in elastic fiber assembly due to the absence of fibulin-5 (Fbln5-/-). We find that Eln+/- arteries have reduced buckling pressure compared to their wild-type controls. Fbln5-/- arteries have similar buckling pressure to wild-type at low axial stretch, but increased buckling pressure at high stretch. We fit material parameters to mechanical test data for Eln+/-, Fbln5-/- and wild-type arteries using Fung and four-fiber strain energy functions. Fitted parameters are used to predict theoretical buckling pressure based on equilibrium of an inflated, buckled, thick-walled cylinder. In general, the theoretical predictions underestimate the buckling pressure at low axial stretch and overestimate the buckling pressure at high stretch. The theoretical predictions with both models replicate the increased buckling pressure at high stretch for Fbln5-/- arteries, but the four-fiber model predictions best match the experimental trends in buckling pressure changes with axial stretch. This study provides experimental and theoretical methods for further investigating the influence of genetic mutations in elastic fibers on buckling behavior and the development of arterial tortuosity. PMID:25771258

Luetkemeyer, Callan M; James, Rhys H; Devarakonda, Siva Teja; Le, Victoria P; Liu, Qin; Han, Hai-Chao; Wagenseil, Jessica E

2015-06-01

150

Cerebral blood flow velocity declines before arterial pressure in patients with orthostatic vasovagal presyncope  

Science.gov (United States)

OBJECTIVES: We studied hemodynamic changes leading to orthostatic vasovagal presyncope to determine whether changes of cerebral artery blood flow velocity precede or follow reductions of arterial pressure. BACKGROUND: Some evidence suggests that disordered cerebral autoregulation contributes to the occurrence of orthostatic vasovagal syncope. We studied cerebral hemodynamics with transcranial Doppler recordings, and we closely examined the temporal sequence of changes of cerebral artery blood flow velocity and systemic arterial pressure in 15 patients who did or did not faint during passive 70 degrees head-up tilt. METHODS: We recorded photoplethysmographic arterial pressure, RR intervals (electrocardiogram) and middle cerebral artery blood flow velocities (mean, total, mean/RR interval; Gosling's pulsatility index; and cerebrovascular resistance [mean cerebral velocity/mean arterial pressure, MAP]). RESULTS: Eight men developed presyncope, and six men and one woman did not. Presyncopal patients reported light-headedness, diaphoresis, or a sensation of fatigue 155 s (range: 25 to 414 s) before any cerebral or systemic hemodynamic change. Average cerebral blood flow velocity (CBFV) changes (defined by an iterative linear regression algorithm) began 67 s (range: 9 to 198 s) before reductions of MAP. Cerebral and systemic hemodynamic measurements remained constant in nonsyncopal patients. CONCLUSIONS: Presyncopal symptoms and CBFV changes precede arterial pressure reductions in patients with orthostatic vasovagal syncope. Therefore, changes of cerebrovascular regulation may contribute to the occurrence of vasovagal reactions.

Dan, Dan; Hoag, Jeffrey B.; Ellenbogen, Kenneth A.; Wood, Mark A.; Eckberg, Dwain L.; Gilligan, David M.

2002-01-01

151

Echocardiographic evaluation of left ventricular diastolic function: an update.  

Science.gov (United States)

Echocardiographic evaluation of diastolic properties and assessment of hemodynamic status of the right and the left ventricle have been traditionally applied for many years in clinical practice. Establishment of diagnosis of diastolic dysfunction, grading, and estimation of filling pressures noninvasively adds prognostic information to the clinician, which may affect treatment management. Novel methods, including left atrium strain, left ventricular diastolic strain rate, and left ventricular untwisting rate, have been imported in clinical practice attempting to provide a more comprehensive and more accurate understanding of the mechanisms and diagnosis of diastolic dysfunction. PMID:25618306

Maragiannis, Dimitrios; Nagueh, Sherif F

2015-02-01

152

Avaliação das pressões sistólica, diastólica e pressão de pulso como fator de risco para doença aterosclerótica coronariana grave em mulheres com angina instável ou infarto agudo do miocárdio sem supradesnivelamento do segmento ST / Evaluation of systolic, diastolic, and pulse pressure as risk factors for severe coronary arteriosclerotic disease in women with unstable angina non-ST-elevation acute myocardial infarction  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese OBJETIVO: Avaliar se as pressões, medidas na raiz da aorta, são fatores de risco para doença aterosclerótica coronariana grave em mulheres com angina instável ou infarto agudo do miocárdio sem supradesnivelamento do segmento ST (AI/IAMSS). MÉTODO:As pressões, assim como os fatores de risco para doen [...] ça arterial coronariana (DAC) foram prospectivamente coletados de março/1993 a agosto/2001 em 593 mulheres com diagnóstico de AI/IAMSS submetidas à cinecoronariografia. Lesões coronarianas definidas como graves estenoses > 70%. RESULTADOS: Idade média de 59,2±11,2 anos, significantemente mais alta nas pacientes com DAC: 61,9 ± 10,8 anos vs 56.4 ± 10,8 anos; tabagismo, diabetes e climatério foram mais freqüentes nas pacientes com DAC. As médias das pressões sistólica e arterial média foram iguais nos dois grupos, entretanto as médias das pressões diastólicas do ventrículo esquerdo (17.6 ± 8.7 x 15.1 ± 8.1, p=0.001) e da pressão de pulso aórtica foram significantemente maiores nas pacientes com DAC (75.5 ± 22 x 70 ± 19, p=0.002), enquanto a média da pressão diastólica aórtica foi significantemente mais alta nas pacientes sem DAC (75.3 ± 17.5 x 79.8 ± 16, p=0.003). Na análise multivariada a pressão de pulso > 80 mmHg e pressão sistólica > 165 foram independentemente associadas a DAC com razão de chance de 2.12 e 2.09, p 80 mmHg e pressão sistólica > 165 mmHg determinaram risco duas vezes maior de lesão coronariana grave. Abstract in english OBJECTIVE: To evaluate pressures assessed at the aortic root as risk factors for severe atherosclerotic coronary heart disease in women with unstable angina/compatible clinical history associated with increase in cardiac enzymes (total CPK and CK-MB) 2 times greater than the standard value used in t [...] he hospital, with the absence of new Q waves on the electrocardiogram (UA/NSTEMI). METHODS: Five hundred and ninety-three female patients with clinical diagnosis of UA/NSTEMI underwent cinecoronariography from March 1993 to August 2001, and the risk factors for CHD were studied. During examination the pressures, at the aortic root, and coronary obstructions were visually assessed by 2 interventional cardiologists, and those stenosis over 70% were considered severe. RESULTS: Eight-one per cent of the population was white and 18.3% was black. Mean age was 59.2±11.2 years, and it was significantly higher in patients with severe coronary lesions: 61.9 ± 10.8 years versus 56.4 ± 10.8 years; smoking, diabetes mellitus and climacteric were more frequent in patients with CHD. The average mean arterial pressure and mean systolic blood pressure was the same in both groups, however, average left ventricle diastolic pressure (17.6 ± 8.7 x 15.1 ± 8.1, p=0.001), and aortic pulse pressure were significantly greater in patients with CHD (75.5 ± 22 x 70 ± 19, p=0.002), while average aortic diastolic pressure was significantly greater in patients without CHD (79.8 ± 16 x 75.3 ± 17.5, p=0.003). In the multivariated analysis, pulse pressure > 80 mmHg and systolic blood pressure > 165 were independently associated with severe CHD with odds ratio of 2.12 and 2.09, p 80 mmHg and systolic blood pressure > 165 mmHG determined risk two times greater of severe coronary disease.

José Marconi Almeida de, Sousa; João L. V., Hermann; João B., Guimarães; Pedro Paulo O., Menezes; Antonio Carlos Camargo, Carvalho.

2004-05-01

153

Drinking and arterial blood pressure responses to ANG II in young and old rats  

OpenAIRE

We investigated water drinking and arterial blood pressure responses to intravenous infusions of ANG II in young (4 mo), middle-aged adult (12 mo), and old (29 mo) male Brown Norway rats. Infusions of ANG II began with arterial blood pressure either at control levels or at reduced levels following injection of the vasodilator minoxidil. Under control conditions, mean arterial pressure (MAP) in response to ANG II rose to the same level for all groups, and middle-aged and old rats drank as much...

Thunhorst, Robert L.; Beltz, Terry G.; Johnson, Alan Kim

2010-01-01

154

Path Length Entropy Analysis of Diastolic Heart Sounds  

OpenAIRE

Early detection of coronary artery disease (CAD) using the acoustic approach, a noninvasive and cost-effective method, would greatly improve the outcome of CAD patients. To detect CAD, we analyze diastolic sounds for possible CAD murmurs. We observed diastolic sounds to exhibit 1/f structure and developed a new method, path length entropy (PLE) and a scaled version (SPLE), to characterize this structure to improve CAD detection. We compare SPLE results to Hurst exponent, Sample entropy and Mu...

Griffel, B.; Zia, M. K.; Fridman, V.; Saponieri, C.; Semmlow, J. L.

2013-01-01

155

Ankle blood pressure measured by automatic oscillotonometry: a comparison with Doppler pressure measurements.  

OpenAIRE

Oscillotonometry using Dinamap machine was investigated for the measurement of ankle and brachial blood pressures in our vascular practice. It was validated by comparison with intra-arterial pressure measured by transducer. Systolic ankle and brachial pressures in 43 patients were compared using the Dinamap and Doppler techniques, and significant correlation was found. Ankle and brachial systolic, diastolic and mean pressures and ankle/brachial pressure indices for all three pressures were me...

Adiseshiah, M.; Cross, F. W.; Belsham, P. A.

1988-01-01

156

Measurement of Blood Pressure Using an Arterial Pulsimeter Equipped with a Hall Device  

OpenAIRE

To measure precise blood pressure (BP) and pulse rate without using a cuff, we have developed an arterial pulsimeter consisting of a small, portable apparatus incorporating a Hall device. Regression analysis of the pulse wave measured during testing of the arterial pulsimeter was conducted using two equations of the BP algorithm. The estimated values of BP obtained by the cuffless arterial pulsimeter over 5 s were compared with values obtained using electronic or liquid mercury BP meters. The...

Jong-Gu Choi; Keun-Ho Kim; Woo-Beom Lee; Dong-Hyun Nam; Il-Ho Son; You-Sik Hong; Sang-Suk Lee

2011-01-01

157

A computational analysis of the long-term regulation of arterial pressure  

OpenAIRE

The asserted dominant role of the kidneys in the chronic regulation of blood pressure and in the etiology of hypertension has been debated since the 1970s. At the center of the theory is the observation that the acute relationships between arterial pressure and urine production—the acute pressure-diuresis and pressure-natriuresis curves—physiologically adapt to perturbations in pressure and/or changes in the rate of salt and volume intake. These adaptations, modulated by various interacti...

Beard, Daniel A.; Pettersen, Klas H.; Carlson, Brian E.; Omholt, Stig W.; Bugenhagen, Scott M.

2013-01-01

158

Altered diastolic function and aortic stiffness in Alzheimer’s disease  

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Full Text Available Ali Nazmi Çalik,3 Kazim Serhan Özcan,4 Gülbün Yüksel,2 Baris Güngör,1 Emre Arugarslan,1 Figen Varlibas,2 Ahmet Ekmekci,1 Damirbek Osmonov,1 Mustafa Adem Tatlisu,1 Mehmet Karaca,1 Osman Bolca,1 Izzet Erdinler1 1Department of Cardiology, Siyami Ersek Cardiovascular and Thoracic Surgery Center, Istanbul, Turkey; 2Department of Neurology, Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey; 3Department of Cardiology, Yozgat State Hospital, Yozgat, Turkey; 4Department of Cardiology, Derince Training and Research Hospital, Kocaeli, Turkey Background: Alzheimer’s disease (AD is closely linked to cardiovascular risk factors.Methods: Echocardiographic studies were performed, including left ventricular diastolic functions, left and right atrial conduction times, and arterial stiffness parameters, namely stiffness index, pressure-strain elastic modulus, and distensibility, on 29 patients with AD and 24 age-matched individuals with normal cognitive function.Results: The peak mitral flow velocity of the early rapid filling wave (E was lower, and the peak velocity of the late filling wave caused by atrial contraction (A, deceleration time of peak E velocity, and isovolumetric relaxation time were higher in the AD group. The early myocardial peak (Ea velocity was significantly lower in AD patients, whereas the late diastolic (Aa velocity and E/Ea ratio were similar between the two groups. In Alzheimer patients, stiffness index and pressure-strain elastic modulus were higher, and distensibility was significantly lower in the AD group compared to the control. Interatrial electromechanical delay was significantly longer in the AD group.Conclusion: Our findings suggest that patients with AD are more likely to have diastolic dysfunction, higher atrial conduction times, and increased arterial stiffness compared to the controls of same sex and similar age. Keywords: diastolic dysfunction, atrial conduction time

Çal?k AN

2014-07-01

159

Comportamento da pressão arterial em filhos de normotensos e filhos de hipertensos submetidos a estímulos pressóricos Arterial blood pressure responses in children of normotensive and hypertensive parents submitted to pressor tests  

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Full Text Available OBJETIVO: Comparar a pressão arterial (PA basal e as respostas a estímulos pressóricos de filhos de normotensos e filhos de hipertensos. MÉTODOS: Foram examinados 32 adolescentes, do sexo masculino, brancos, na faixa etária entre 13 e 18 anos, sendo que 16 eram filhos de hipertensos e 16 filhos de normotensos. Para cada indivíduo foi aferida a PA basal seguida da aplicação de três testes pressóricos: teste do exercício isométrico com o handgrip, teste pressor ao frio e teste do exercício aritmético mental. Para a aferição da PA foi utilizado um dispositivo oscilométrico, digital, previamente calibrado. RESULTADOS: Os filhos de hipertensos exibiram valores basais de PA, tanto sistólica quanto diastólica, maiores que os filhos de normotensos (pPURPOSE: To compare cardiovascular reactivity in adolescents with and without family history of hypertension. METHODS: Thirty two subjects, males, students, aging between 13 to 18 years old were examined. One half of them had no family history of hypertension and the other half had at least one hypertensive parent. Basal blood pressure level was obtained before the application of the following selected tests: isometric handgrip exercise test, cold pressor test and arithmetic mental stress test. The blood pressure values were obtained by a digital, oscilometric device, previously calibrated. RESULTS: The subjects with family history of hypertension exhibited higher basal levels of both systolic and diastolic blood pressure (p<0,10. Concerning the tests applied, the subjects with family history of hypertension also exhibited higher responses, but only the response of the diastolic blood pressure to the mental stress test was statistically significant (p<0,10. CONCLUSION: Our findings point to the need of a special follow-up of children with a family history of hypertension.

José Wilson S. Cavalcante

1997-11-01

160

Uniform Transmural Strain in Pre-Stressed Arteries Occurs at Physiological Pressure  

OpenAIRE

Residual deformation (strain) exists in arterial vessels, and has been previously proposed to induce homogeneous transmural strain distribution. In this work, we present analytical formulations that predict the existence of a finite internal (homeostatic) pressure for which the transmural deformation is homogenous, and the corresponding stress field. We provide evidence on the physical existence of homeostatic pressure when the artery is modeled as an incompressible tube with orthotropic cons...

Destrade, Michel; Liu, Yi; Murphy, Jeremiah G.; Kassab, Ghassan S.

2012-01-01

161

Acompanhamento da pressão arterial: estudo com crianças e adolescentes com história familiar de hipertensão Acompañamiento de la presión arterial: investigación con niños y adolescentes con historia familiar de hipertensión Blood pressure tracking: study with children and adolescents with familial history of hypertension  

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Full Text Available Objetivou-se analisar a evolução dos percentis de pressão arterial em crianças e adolescentes com história familiar de hipertensão arterial. Estudo longitudinal desenvolvido em uma comunidade de Fortaleza, Ceará. A pressão arterial foi avaliada em cinco encontros domiciliares, de janeiro de 2004 a dezembro de 2006. Grupo de 141 participantes, dos quais 92 crianças e 49 adolescentes. Das crianças, 67,4% permaneceram sem alterações dos percentis de pressão arterial em todas as avaliações; dos adolescentes, 65,3% permaneceram nesta condição. A maior parte dos indivíduos mantiveram seus valores e percentis de pressões arteriais sistólica e diastólica elevados, e muitos que não apresentavam inicialmente alterações passaram a mostrá-las no decorrer do acompanhamento. Confirma-se a necessidade de monitoração da pressão arterial rotineira de crianças e adolescentes tanto para a detecção precoce como para a prevenção de complicações.El objetivo fue analizar la evolución de los percentiles de presión arterial en niños y adolescentes con historia familiar de hipertensión arterial. Estudio longitudinal en una comunidad de Fortaleza, Ceará, Brasil. La presión arterial fue evaluada en cinco encuentros en los sitios, de enero de 2004 a diciembre de 2006. El grupo fue de 141 participantes, de los cuales 92 niños y 49 adolescentes. De los niños, 67,4% permanecieron sin alteraciones de los percentiles de presión arterial en todas las evaluaciones; de los adolescentes, 65,3% permanecieron en ésta condición. La mayor parte de los individuos mantenieron sus valores y percentiles de presión arterial sistólica y presión arterial diástolica muy altos, y muchos que no presentaban inicialmente alteraciones, pasaron a señalalas en el decurrir del acompañamiento. Así, se comprueba la necesidad de monitoración de la presión arterial rutinera de niños y adolescentes tanto para la detección como para la prevención de complicaciones.The purpose of this study is to analyze the evolution of the percentiles of blood pressure in children and adolescents with familial history of arterial hypertension. This is a longitudinal study developed in a community in Fortaleza, Ceará, Brazil. The blood pressure was evaluated in five home visits from January, 2004 to December, 2006. The group was composed of 141 participants, of which 92 were children and 49 adolescents. Of the children, 67,4% remained with no alterations of the percentiles of blood pressure in all the evaluations; of the adolescents, 65,3% remained in the same condition. Most individuals kept their values and percentiles of systolic blood pressure and diastolic blood pressure, and many that did not initially present alterations started to show some during the follow up. As a result, routine monitoring of blood pressure of children and adolescents proves necessary for the early detection and prevention of complications.

Emilia Soares Chaves

2010-03-01

162

Arterial blood pressure regulation following aorta clamping and declamping during surgery.  

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In this paper, we propose the use of black box models for the system identification of the cardiopulmonary baroreflex control of arterial resistance and of ventricular contractility and of arterial baroreflex control of heart rate (HR) from invasive, continuous measurements of arterial blood pressure (ABP) and central venous pressure (CVP), and non invasive, continuous recordings of ECG and respiration. Two crucial phases of the abdominal aortic aneurism (AAA) repair were investigated: the clamping and declamping of aorta. The objective of the present work is to evaluate and to test the ability to monitor baroreflex responses to clamping and declamping maneuvers preceding and following aneurism removal. PMID:22256303

Ferrario, Manuela; Aletti, Federico; Toschi, Nicola; Canichella, Antonio; Coniglione, Filadelfo; Sabato, Elisabetta; Della Badia Giussi, Florencia; Dauri, Mario; Sabato, Alessandro F; Guerrisi, Maria; Cerutti, Sergio

2011-01-01

163

FSI simulation for the analysis of pulse wave velocity in artery  

International Nuclear Information System (INIS)

In this study, we developed an arterial network model to simulate the arterial pressures and PWV (Pulse Wave Velocity) in arteries. The model can provide the clinician with a more refined method of non-invasively determining the hemodynamics. It is based upon a numerical solution of the one-dimensional fluid-structure interaction in a geometrically accurate branching network of the arterial system including energy losses at bifurcations. Using this method, we simulated the pulse wave velocity in arterial networks and evaluated the effect of arterial wall stiffening on PWV. Computational results showed that the PWV increased according to arterial wall stiffening. For the stiffened artery, systolic blood pressure increased whereas the diastolic pressure decreased, indicating that arterial wall stiffening can give rise to ventricular hypertrophy.

164

Effect of topical ketanserin administration on intraocular pressure.  

OpenAIRE

The effect of topical ketanserin on intraocular pressure (IOP) in normotensive and hypertensive eyes was evaluated. The study was performed on 10 healthy volunteers and 10 glaucomatous patients. Systolic arterial blood pressure (SBP), diastolic arterial blood pressure (DBP), heart rate (HR), IOP, tonographic outflow facility, pupil diameter, corneal thickness, and tear secretion were recorded at baseline and at 1 hour intervals for 12 hours after topical administration of 0.5% ketanserin or p...

Costagliola, C.; Iuliano, G.; Rinaldi, M.; Russo, V.; Scibelli, G.; Mastropasqua, L.

1993-01-01

165

Spontaneous changes in arterial blood pressure and renal interstitial hydrostatic pressure in conscious rats.  

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1. Previous work has demonstrated a positive relationship between experimentally induced changes in arterial pressure (AP) and renal interstitial hydrostatic pressure (RIHP). The purpose of the present study was to test the hypothesis that RIHP is positively correlated with the normal changes in AP that occur spontaneously in conscious rats. 2. Rats were chronically instrumented for the recording of AP (via an aortic catheter) and RIHP. RIHP was measured by implanting a Millar microtransducer, whose tip had been encapsulated in a 35 microns pore polyethylene matrix (5 mm long, 2 mm o.d.), approximately 5 mm below the renal cortical surface. 3. A total of 56 h of simultaneous analog recording of AP and RIHP was obtained from ten rats. Each 1 h segment was digitized and evaluated at frequencies of 1, 0.1, 0.02 and 0.01 Hz. 4. In forty-nine out of fifty-six of these 1 h recordings taken at 1 Hz, there were significant positive linear correlations between AP and RIHP (mean r = 0.32) with a mean slope of 0.11 mmHg RIHP/1 mmHg AP. Low-pass filtering to 0.01 Hz significantly increased the r value to 0.48. 5. These results demonstrate that spontaneous changes in AP and RIHP are positively correlated. The spontaneous coupling of AP and RIHP may be of importance in the regulation of salt and water excretion by the pressure diuresis mechanism. PMID:7707240

Skarlatos, S; Brand, P H; Metting, P J; Britton, S L

1994-12-15

166

Intra-arterial Infusion of Leptin does not Affect Blood Pressure in Salt-loaded Rabbits  

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Full Text Available The aim of this research is to see the effect of intra-arterial infusion of leptin on blood pressure of salt loaded rabbits in vivo. Increased blood pressure was produced in rabbits by giving diets containing 8% sodium chloride for 5 weeks. Leptin in different concentrations was infused intra-arterially into rabbits fed on high salt diets and the response was compared in rabbits fed with low salt diets. High salt diets produced significant increase in blood pressure. In rabbits fed with low salt diet, leptin infused intra-arterially caused an increase in blood pressure while infusion of leptin into rabbits fed with high salt diets does not affect the blood pressure. In conclusion, salt loading to rabbits abolishes the effect of leptin on cardiovascular system. This may indicate that leptin effect on sympathetic activity is altered by high salt diets in these animals.

Mohammad Nidal Khabaz

2010-01-01

167

Decrease of blood pressure by community-based strategies / Descenso de la presión arterial por estrategias comunitarias  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: English Abstract in spanish La ciudad de Rauch presentaba en 1997 alta prevalencia de hipertensión arterial (HA) y bajos niveles de tratamiento y control. Para evaluar el impacto de actividades de intervención comunitarias sobre la presión arterial (PA) reencuestamos en el año 2003 a una cohorte de 1526 habitantes de 15-75 año [...] s. Las actividades de intervención fueron el estudio inicial, la indicación de concurrir a su médico cuando se hallaban alteraciones, la provisión gratuita de antihipertensivos y la difusión por medios masivos de los resultados del estudio y de hábitos saludables de vida. La PA fue medida en el domicilio por enfermeras especialmente entrenadas, considerando PA sistólica y diastólica (PAS y PAD) a los promedios de tres registros en una ocasión. Se reencuestaron 1307 individuos (85.65%). La PAS descendió de 137.98 ± 0.57 a 132.49 ± 0.53 mm Hg (p Abstract in english In a cross section study performed in Rauch in 1997 we found a high prevalence of hypertension and low levels of treatment and control. To evaluate the impact of the community-based intervention activities on blood pressure (BP), we made a cohort study in 1526 inhabitants aged between 15 and 75 year [...] s in 2003. The initial study, the advice to consult the family doctor when alterations were found, the free provision of antihypertensive drugs, the press diffusion of the study results and a healthy lifestyle were included among the intervention activities. BP was measured in the subjects' residence by especially trained nurses, considering systolic BP (SBP) and diastolic BP (DBP) as the average of three measurements in one occasion. A total of 1307 subjects (85.65%) were re-interviewed. SBP decreased from 137.98 ± 0.57 to 132.49 ± 0.53 mm Hg (p

Martín R., Salazar; Horacio A., Carbajal; Marcelo, Aizpurua; Beatriz, Riondet; Horacio F., Rodrigo; Valentín, Rechifort; Susana M., Quaini; Raúl F., Echeverria.

2005-12-01

168

Optimizing mean arterial pressure in septic shock: a critical reappraisal of the literature.  

Science.gov (United States)

Guidelines recommend that a mean arterial pressure (MAP) value greater than 65 mm Hg should be the initial blood pressure target in septic shock, but what evidence is there to support this statement? We searched Pubmed and Google Scholar by using the key words 'arterial pressure', 'septic shock', and 'norepinephrine' and retrieved human studies published between 1 January 2000 and 31 July 2014. We identified seven comparative studies: two randomized clinical trials and five observational studies. The results of the literature review suggest that a MAP target of 65 mm Hg is usually sufficient in patients with septic shock. However, a MAP of around 75 to 85 mm Hg may reduce the development of acute kidney injury in patients with chronic arterial hypertension. Because of the high prevalence of chronic arterial hypertension in patients who develop septic shock, this finding is of considerable importance. Future studies should assess interactions between time, fluid volumes administered, and doses of vasopressors. PMID:25777887

Leone, Marc; Asfar, Pierre; Radermacher, Peter; Vincent, Jean-Louis; Martin, Claude

2015-12-01

169

Variabilidad de la medición de la presión arterial en Pediatría: estudio de práctica clínica Variability of the blood pressure measurement in Pediatrics. A clinical practice study  

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Full Text Available Objetivo. Estudiar la precisión y concordancia de la medición de presión arterial en pacientes pediátricos con dispositivos aneroides y oscilométricos de uso común.
Métodos. Estudio transversal de evaluación de medidas repetidas con distintos dispositivos y diferentes observadores de la presión arterial en una muestra consecutiva de 121 pacientes pediátricos mayores de 4 años ingresados. Análisis de la adecuación del tamaño del manguito empleado a las medidas de perímetro y longitud del brazo y su repercusión en la concordancia entre medidas. Estimación de medias y diferencias de medidas repetidas, coeficientes de correlación intraclase y análisis de Bland-Altman.
Resultados. Las mediciones realizadas con el dispositivo oscilométrico superaron a las del aneroide (2,6 unidades para la sistólica y 1,5 para la diastólica. La diferencia entre métodos se asociaba discretamente a un desajuste con respecto al perímetro del brazo, tanto para la presión sistólica (sobreestimación media 2,55 mmHg como para la diastólica (sobrestimación media de 2,44 mmHg. La concordancia entre medidas repetidas fue alta y aceptable entre dispositivos. Las diferencias medias y sus intervalos de concordancia fueron para la tensión sistólica de 2,6 mmHg (-8,3 a +13,5 y para la diastólica 1,5 mmHg (-11,4 a +14,4. Todas las diferencias se adecuaban al grado A de la British Hypertension Society, salvo para el criterio de 5 mmHg de la presión arterial diastólica (grado C.
Conclusiones. Considerando la aceptable precisión, la facilidad de aplicación y la objetividad de los dispositivos oscilométricos parece recomendable su uso como método de cribado habitual, aunque, mientras no esté aclarada la validez de sus mediciones, si éstas se sitúan en valores anormales, deberían confirmarse con otros instrumentos. Objective. To study the reliability and consistency of measuring blood pressure in pediatric patients with aneroid and oscillometric devices of common use.
Methods. A cross-sectional was carried out, with evaluation of repeated measurements of blood pressure by different devices and observers in a sample of 121 consecutive pediatric hospitalised patients over 4 years old. The adequacy of cuff size used to the measures of perimeter and length of arm and its impact on the consistency between measures were analyzed. Means and differences of repeated measurements, intraclass correlation coefficients and Bland-Altman analysis were estimated.
Results. The measurements with the oscillometric device exceeded those of the aneroid (2.6 units for systolic and 1.5 for diastolic. The difference between methods was associated discreetly to a mismatch with respect to arm circumference, both for systolic pressure (mean overestimation of 2.55 mmHg and for diastolic (mean overestimation of 2.44 mmHg. The agreement between repeated measures was high and between devices acceptable. Mean differences and their concordance intervals ranges were for systolic blood pressure of 2.6 mmHg (-8.3 to +13.5 and for diastolic 1.5 mmHg (-11.4 to 14.4. All differences were suitable for the A grade of the British Hypertension Society, except for the criterion of 5 mm Hg of the diastolic blood pressure (Grade C.
Conclusions. Considering the acceptable accuracy, ease of application and the objectivity of oscillometric devices, they seem recommendable for use as a common screening method, though, while the validity of their measurements was not clarified, whether they are at abnormal levels, should be confirmed with other instruments.

N. Rodríguez Arias

2011-01-01

170

Relationship between mean arterial pressure and end-tidal partial pressure of carbon dioxide during hemorrhagic shock and volume resuscitation  

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Full Text Available Objectives. We examined the relationship between partial end-tidal CO2 (pet and mean arterial pressure in patients with traumatic hemorrhagic shock, who were receiving constant minute ventilation.Methods. In 61 patients we continuously measured pet CO2 with a capnograph, direct arterial pressure via a cannula, oxygen levels via pulse oximetry and body temperature.Results. We observed significant changes in pet CO2 (increase after volume resuscitation and a quantitative linear relationship between pet CO2 and mean arterial pressure.Conclusions. Partial end-tidal CO2 can be used as a reliable non-invasive monitoring device in patients with hemorrhagic shock when minute ventilation is relatively constant. The monitoring of pet CO2 might also be a useful guide for volume resuscitation in hemorrhagic shock, especially in the pre-hospital setting.

Stefek Grmec

2009-04-01

171

Assessment of the changes in blood pressure circadian profile and variability in patients with chronic heart failure and arterial hypertension during combined therapy including ivabradine  

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Full Text Available Aim. To assess the changes in blood pressure (BP circadian profile and variability in patients with chronic heart failure (CHF of ischemic etiology and arterial hypertension (HT due to the complex therapy including ivabradine.Material and methods. Patients (n=90 with CHF class II–III NYHA associated with stable angina II-III class and HT were examined. The patients were randomized into 3 groups depending on received drugs: perindopril and ivabradine - group 1; perindopril, bisoprolol and ivabradine - group 2; perindopril and bisoprolol - group 3. The duration of therapy was 6 months. Ambulatory BP monitoring (ABPM was assessed at baseline and after treatment.Results. More significant reduction in average 24-hours systolic BP was found in groups 1 and 2 compared to group 3 (?%: -19.4±0,4; -21.1±0.4 and -11.8±0.6, respectively as well as diastolic BP (?%: -10.6±0.6; -12.9±0.4 and -4,3±0.3, respectively and other ABPM indicators. Improvement of BP circadian rhythm was found due to increase in the number of «Dipper» patients (p=0.016. More significant reduction in average daily and night systolic and diastolic BP (p=0.001, as well as daily and night BP variability (p=0.001 was also found in patients of group 2 compared to these of group 1.Conclusion. Moderate antihypertensive effect (in respect of both diastolic and systolic BP was shown when ivabradine was included into the complex therapy of patients with ischemic CHF and HT. The effect was more pronounced when ivabradine was combined with perindopril and bisoprolol. This was accompanied by reduction in high BP daily variability and improvement of the BP circadian rhythm.

M.V. Surovtseva

2012-10-01

172

External negative thigh pressure. Effect upon blood flow and pressure in the foot in patients with occlusive arterial disease.  

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We studied the effect of external application of 35-45 mmHg negative pressure around the thigh on toe blood pressure and skin blood flow in nine patients with occlusion of the superficial femoral artery and rest pain/severe intermittent claudication. The systolic toe blood pressure increased from 32 (range 5-70) mmHg before treatment to 57 (42-75) mmHg (p less than 0.05) during negative thigh pressure and 44 (range 10-88) mmHg after treatment. In addition, the gain in toe blood pressure tended to be greater the lower the pre-test toe pressure was, correlation coefficient r = 0.52 (p greater than 0.05). Relative skin blood flow, measured in the first toe interstice by the 133Xe wash-out method, increased by 304 (range 86-767) percent (p less than 0.05) during the test period compared to the mean wash-out rate obtained before and following the test period. Heart rate, systemic blood pressure, skin temperature, serum protein and haematocrit measured during each phase of the study were similar. We conclude that 35-45 mmHg negative pressure around the thigh in patients with occlusion of the superficial femoral artery induce increased blood perfusion in the foot, possibly due to changes in collateral arterial resistance in the thigh. PMID:2272212

Agerskov, K; Tofft, H P; Jensen, F B; Engell, H C

1990-10-01

173

Low-pressure pulmonary artery aneurysm presenting with pulmonary embolism: a case series  

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Full Text Available Abstract Introduction Pulmonary artery aneurysm is an uncommon disorder with severe complications. The diagnosis is often difficult, since the clinical manifestations are non-specific and the treatment is controversial, as the natural history of the disease is not completely understood. Case presentation We describe the cases of two patients with pulmonary artery aneurysms. The first patient was a 68-year-old Caucasian man with an idiopathic low-pressure pulmonary artery aneurysm together with a pulmonary embolism. The patient preferred a conservative approach and was stable at the 10-month follow-up visit after being placed on anti-coagulant treatment. The second patient was a 66-year-old Caucasian woman with a low-pressure pulmonary artery aneurysm also presented together with a pulmonary embolism. The aneurysm was secondary to pulmonary valve stenosis. She received anti-coagulants and, after stabilization, underwent percutaneous balloon valvuloplasty. Conclusion Pulmonary embolism may be the initial presentation of a low-pressure pulmonary artery aneurysm. No underlying cause for pulmonary embolism was found in either of our patients, suggesting a causal association with low-pressure pulmonary artery aneurysm.

Papoulidis Pavlos

2011-04-01

174

Velocidade da onda de pulso, pressão arterial e adipocitocinas em adultos jovens: estudo do Rio de Janeiro / Pulse wave velocity, blood pressure and adipocytokines in young adults: the Rio de Janeiro study  

Scientific Electronic Library Online (English)

Full Text Available FUNDAMENTO: Dados sobre a avaliação não invasiva vascular e suas relações com variáveis de risco cardiovascular são escassos em jovens. OBJETIVO: Avaliar a relação entre a velocidade de onda de pulso e a pressão arterial,variáveis antropométricas e metabólicas, incluindo as adipocitocinas, em indiví [...] duos adultos jovens. MÉTODOS: Foram avaliados 96 indivíduos (51 homens) do estudo do Rio de Janeiro, de 26 a 35 anos (média 30,09 ± 1,92). Foram obtidos a velocidade de onda de pulso (método Complior), pressão arterial, índice de massa corporal, glicose, perfil lipídico, leptina, insulina, adiponectina e o índice de resistência à insulina HOMA-IR. Os indivíduos foram estratificados em três grupos segundo o tercil da VOP para cada sexo. RESULTADOS: O grupo com maior tercil de VOP mostrou maiores médias de pressão arterial sistólica, pressão arterial diastólica, pressão arterial média, índice de massa corporal, insulina, HOMA-IR e menores médias de adiponectina, além de maiores prevalências de diabetes mellitus/intolerância à glicose e hiperinsulinemia. Houve correlação significativa e positiva da velocidade da onda de pulso com pressão arterial sistólica, pressão arterial diastólica, pressão de pulso e pressão arterial média, índice de massa corporal, e LDL-colesterol e negativa com HDL-colesterol e adiponectina. Em modelo de regressão múltipla, após ajuste do HDL-colesterol, LDL-colesterol e adiponectina para sexo, idade, índice de massa corporal e pressão arterial média, apenas o sexo masculino e a pressão arterial média mantiveram correlação significativa com a velocidade de onda de pulso. CONCLUSÃO: A velocidade de onda de pulso em adultos jovens mostrou relação significativa com variáveis de risco cardiovascular, destacando-se o sexo masculino e a pressão arterial média como importantes variáveis no seu determinismo. Os achados sugerem que a medida da VOP pode ser útil para a identificação do acometimento vascular nessa faixa etária. Abstract in english BACKGROUND: Data on noninvasive vascular assessment and their association with cardiovascular risk variables are scarce in young individuals. OBJECTIVE: To evaluate the association between pulse wave velocity and blood pressure, anthropometric and metabolic variables, including adipocytokines, in yo [...] ung adults. METHODS: A total of 96 individuals aged 26 to 35 years (mean 30.09 ± 1.92; 51 males) were assessed in the Rio de Janeiro study. Pulse wave velocity (Complior method), blood pressure, body mass index, glucose, lipid profile, leptin, insulin, adiponectin and insulin resistance index (HOMA-IR) were analyzed. Subjects were stratified into three groups according to the PWV tertile for each gender. RESULTS: The group with the highest pulse wave velocity (PWV) tertile showed higher mean systolic and diastolic blood pressure, mean blood pressure, body mass index, insulin, and HOMA-IR, as well as lower mean adiponectin; higher prevalence of diabetes mellitus/glucose intolerance and hyperinsulinemia. There was a significant positive correlation of PWV with systolic blood pressure, diastolic blood pressure, pulse pressure and mean blood pressure, body mass index, and LDL-cholesterol, and a negative correlation with HDL-cholesterol and adiponectin. In the multiple regression model, after adjustment of HDL-cholesterol, LDL-cholesterol and adiponectin for gender, age, body mass index and mean blood pressure, only the male gender and mean blood pressure remained significantly correlated with PWV. CONCLUSION: PWV in young adults showed a significant association with cardiovascular risk variables, especially in the male gender, and mean blood pressure as important determinant variables. The findings suggest that PWV measurement can be useful for the identification of vascular impairment in this age group.

Oswaldo Luiz, Pizzi; Andréa Araujo, Brandão; Roberto, Pozzan; Maria Eliane Campos, Magalhães; Erika Maria Gonçalves, Campana; Flavia Lopes, Fonseca; Elizabete Viana de, Freitas; Ayrton Pires, Brandão.

2013-01-01

175

Contexto, percepción de la situación económica y cifras de la tensión arterial / Context, perception of the economic situation and blood pressure figures  

Scientific Electronic Library Online (English)

Full Text Available Introducción: todas las actividades humanas están influenciadas por un contexto, y cualquier atributo, característica o indicador está condicionado por este. La percepción de la situación económica es una de las variables que se ha estudiado en el contexto de la epidemiologia social en las investiga [...] ciones que valoran la autoeficacia y las expectativas de resultados vinculadas con la salud. La hipertensión constituye uno de los factores de riesgo para las enfermedades del corazón. Objetivos: estimar la influencia de la percepción de la situación económica por policlínicos sobre las cifras de tensión arterial. Métodos: estudio descriptivo mediante un muestreo probabilístico de las familias en 12 consultorios del médico y la enfermera de la familia, pertenecientes a siete policlínicos de La Habana. Se recogieron variables como la edad, valoración individual de la percepción de la situación económica. Se empleó como escala de valoración: 1. Excelente, 2. Buena, 3. Regular, 4. Mala y 5. Muy Mala. Se realizaron mediciones individuales (adultos entrevistados) resultantes del examen físico y antropométrico: peso, talla, índice de masa corporal, circunferencia de la cintura y tensión arterial. Resultados: se encontró que los que aprecian que su condición económica es mala o muy mala tienen más alta densidades de hipertensos en las familias. Existe un claro gradiente de la tensión arterial sistólica y diastólica según percepción de la situación económica. Según va empeorando la percepción de la situación económica los valores estandarizados de la tensión arterial van aumentando, sin embargo, por policlínicos se aprecia que las trayectorias de la tensión arterial sistólica y diastólica no son paralelas. Conclusiones: el patrón de asociaciones entre ciertos factores individuales y las cifras de tensión arterial cambiaron de un policlínico a otro. Se pone de manifiesto la modulación de efecto que ejerce el contexto sobre el impacto de los factores individuales y la necesidad de incluir la percepción de la condición económica como correlato de las condiciones de salud en futuros estudios epidemiológicos. Abstract in english Introduction: all human activities occur in a context. Attributes, characteristics and indicators are conditioned by their context. Perception of the economic situation is one of the social epidemiology variables used in research about the self-efficacy and expectations of health outcomes. Hypertens [...] ion is a risk factor for heart disease. Objectives: estimate the influence of perception of the economic situation by polyclinics upon blood pressure figures. Methods: a descriptive study was conducted based on probabilistic sampling of the families in 12 family doctor's and nurse's consultation offices from seven polyclinics in Havana. The variables analyzed were age and individual assessment of the perception of the economic situation. The following assessment scale was used: 1. Excellent, 2. Good, 3. Fair, 4. Bad and 5. Very Bad. During the physical and anthropometric examination of the adults surveyed, the following measurements were taken: weight, height, body mass index, waist circumference and blood pressure. Results: a higher number of hypertensives was found in families that perceive their economic situation as bad or very bad. There is a clear relationship between perception of the economic situation and systolic and diastolic blood pressure. Standardized blood pressure values rise as perception of the economic situation worsens. However, as viewed by polyclinics, systolic and diastolic blood pressure trajectories are not parallel. Conclusions: the pattern of association between certain individual factors and blood pressure figures varies between polyclinics. A modulation effect is exerted by the context upon the impact of individual factors. Perception of the economic situation should be included as a correlate of health conditions in future epidemiological studies.

Georgia, Díaz-Perera Fernández; Jorge, Bacallao Gallestey; Eduardo, Alemañy Pérez.

2014-04-01

176

Effects of ductus arteriosus occlusion on pulmonary artery pressure during in utero ventilation in fetal sheep.  

Science.gov (United States)

Seven fetal sheep were prepared to study the short-term effects of in utero ventilation and ductus arteriosus occlusion on pulmonary artery pressure and on fetal right ventricular function assessed using the right atrial pressure-right ventricular stroke volume relationship. Nine days post-surgery (140 days gestation), blood gas and haemodynamic values were obtained before and during in utero ventilation with 100% O2, and during ventilation with the ductus arteriosus occluded. Oxygen content increased significantly from 7.2 to 14.5 ml dl-1 with ventilation and remained elevated at 14.4 ml dl-1 with ventilation with the ductus arteriosus occluded. In utero ventilation produced a left to right atrial pressure gradient and depression of the right atrial pressure-right ventricular stroke volume relationship. Ductus arteriosus occlusion during in utero ventilation reduced the left to right atrial pressure gradient, and along with a decrease in pulmonary artery pressure, resulted in an upward shift of the right atrial pressure-right ventricular stroke volume relationship, but only to the preventilation level. This study indicates that the fetal right atrial pressure-right ventricular stroke volume relationship is significantly altered, both by changes in the left to right atrial pressure gradient and by changes in pulmonary artery pressure seen with in utero ventilation and subsequent ductus arteriosus occlusion. PMID:7734132

Giraud, G D; Morton, M J; Reid, D L; Reller, M D; Thornburg, K L

1995-01-01

177

Diastolic dysfunction in Diabetes Mellitus  

Directory of Open Access Journals (Sweden)

Conclusion: Echocardiography is a sensitive method to investigate for diastolic dysfunction. There is a high prevalence of diastolic dysfunction in diabetes, which is an early marker of diabetic cardiomyopathy. [Natl J Med Res 2013; 3(3.000: 249-252

Nikhil M Dikshit

2013-06-01

178

Effects of smoking cessation on central blood pressure and arterial stiffness  

OpenAIRE

Takeshi Takami1,Yoshihiko Saito21Department of Internal Medicine, Clinic Jingumae, Kashihara, Nara, Japan; 2First Department of Internal Medicine, Nara Medical University, Kashihara, Nara, JapanPurpose: Smoking affects arterial stiffness, thus causing an elevation in central blood pressure (CBP). The present study was designed to examine whether smoking cessation treatment improved CBP and arterial stiffness.Patients and methods: We conducted an observational study of 70 patients receiving sm...

Takami T; Saito Y

2011-01-01

179

The compliance of the porcine pulmonary artery depends on pressure and heart rate  

OpenAIRE

1. The influence of mean pulmonary arterial pressure (mean Ppa) on dynamic (Cd) and pseudo-static compliance (Cps) of the pulmonary artery was studied at a constant and a changing heart rate. Cd is the change in cross-sectional area (CSA) relative to the change in Ppa throughout a heart cycle. Cps is the change in mean CSA relative to the change in mean Ppa. If Cd is known, pulmonary blood flow can be computed from the Ppa ...

Kornet, L.; Jansen, J. R. C.; Nijenhuis, F. C. A. M. Te; Langewouters, G. J.; Versprille, A.

1998-01-01

180

Numerical simulation of blood flow and pressure drop in the pulmonary arterial and venous circulation  

OpenAIRE

A novel multiscale mathematical and computational model of the pulmonary circulation is presented and used to analyse both arterial and venous pressure and flow. This work is a major advance over previous studies by Olufsen and coworkers (Ottesen et al., 2003; Olufsen et al., 2012) which only considered the arterial circulation. For the first three generations of vessels within the pulmonary circulation, geometry is specified from patient-specific measurements obtained using magnetic resonanc...

Qureshi, M. Umar; Vaughan, Gareth D. A.; Sainsbury, Christopher; Johnson, Martin; Peskin, Charles S.; Olufsen, Mette S.; Hill, N. A.

2014-01-01

181

Understanding the contribution of Guyton's large circulatory model to long-term control of arterial pressure  

OpenAIRE

With the publication in 1972 of a large computer model of circulatory control, Guyton and colleagues challenged the then prevailing views on how blood pressure and cardiac output were controlled. At that time, it was widely accepted that the heart controlled cardiac output and that peripheral resistance controlled arterial blood pressure. By incorporating the empirically demonstrated concepts of blood flow autoregulation and the pressure–natriuresis relationship into their mathematical mode...

Montani, Jean-pierre; Vliet, Bruce N.

2009-01-01

182

Variação da Pressão Arterial em Usuárias de Terapia de Reposição Hormonal Variation of Blood Pressure in Users of Hormone Replacement Therapy  

Directory of Open Access Journals (Sweden)

Full Text Available Objetivo: avaliar os efeitos da terapia de reposição hormonal sobre a pressão arterial sistólica e diastólica de mulheres na pós-menopausa. Casuística e Métodos: foram avaliadas retrospectivamente 166 usuárias e 136 não-usuárias de reposição hormonal, acompanhadas no Ambulatório de Menopausa do Centro de Atenção Integral à Saúde da Mulher da Universidade Estadual de Campinas por um período de três anos. Avaliamos a variação desses parâmetros em relação aos valores iniciais. A análise dos dados foi realizada usando-se o teste t de Student, o Teste de Mann-Whitney e o teste não-paramétrico de Wilcoxon. Resultados: observou-se que a pressão arterial sistólica das usuárias de terapia de reposição hormonal foi menor ao final do terceiro ano de uso quando comparada com os valores iniciais (p = 0,01. Não houve diferença significativa na pressão arterial diastólica entre as usuárias e as não-usuárias. Conclusão: a terapia de reposição hormonal não produziu alterações nos parâmetros estudados em mulheres adequadamente acompanhadas durante o seu uso.Purpose: to evaluate the effects of hormone replacement therapy (HRT on the systolic and diastolic blood pressure of postmenopausal women. Methods: a total of 166 users and 136 non-users of hormone replacement were evaluated retrospectively during a period of three years. All women were assisted at the Menopause Outpatient Clinic of CAISM -- Unicamp, where the variations of these parameters were evaluated at the end of each year in relation to the initial parameters. The data analysis was performed through Student's t test, Mann-Whitney test, and the Wilcoxon nonparametric test. Results: we observed that the systolic blood pressure of HRT users was statistically lower at the end of the third year of use, compared to the initial values (p = 0.01. There was no significant difference in the diastolic blood pressure between users and non-users. Conclusion: hormone replacement therapy did not produce changes in the parameters studied in women properly assisted during the use of HRT.

José Alaércio de Toledo Lima-Junior

2000-06-01

183

Pulse transit time as a surrogate measure of changes in systolic arterial pressure in children during sleep.  

Science.gov (United States)

Pulse transit time has been proposed as a surrogate measure of systolic arterial pressure, as it is dependent upon arterial stiffness. Past research has shown that pulse transit time has a significant inverse relationship to systolic arterial pressure in adults; however, studies in children are limited. This study aimed to explore the relationship between systolic arterial pressure and pulse transit time in children during sleep. Twenty-five children (13.1 ± 1.6 years, 48% male) underwent overnight polysomnography (PSG) with a simultaneous recording of continuous systolic arterial pressure and photoplethysmography. Pulse transit time was calculated as the time delay between the R-wave peak of the electrocardiogram (ECG) to the 50% point of the upstroke of the corresponding photoplethysmography waveform; 500 beats of simultaneous systolic arterial pressure and pulse transit time were analysed in each sleep stage for each child. Pulse transit time was normalized to each subject's mean wake pulse transit time. The ability of pulse transit time to predict systolic arterial pressure change was determined by linear mixed-effects modelling. Significant negative correlations between pulse transit time and systolic arterial pressure were found for individual children for each sleep stage [mean correlations for cohort: non-rapid eye movement (NREM) sleep 1 and 2 r = -0.57, slow wave sleep (SWS) r = -0.76, REM r = -0.65, P sleep stage (P < 0.001). The model of pulse transit time-predicted systolic arterial pressure closely tracked actual systolic arterial pressure changes over time. This study demonstrated that pulse transit time was accurate in tracking systolic arterial pressure changes over time. Thus, the use of pulse transit time as a surrogate measure of changes in systolic arterial pressure in children is a valid, non-invasive and inexpensive method with many potential applications. PMID:24605887

Vlahandonis, Anna; Biggs, Sarah N; Nixon, Gillian M; Davey, Margot J; Walter, Lisa M; Horne, Rosemary S C

2014-08-01

184

Comportamento da pressão arterial em filhos de normotensos e filhos de hipertensos submetidos a estímulos pressóricos / Arterial blood pressure responses in children of normotensive and hypertensive parents submitted to pressor tests  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Comparar a pressão arterial (PA) basal e as respostas a estímulos pressóricos de filhos de normotensos e filhos de hipertensos. MÉTODOS: Foram examinados 32 adolescentes, do sexo masculino, brancos, na faixa etária entre 13 e 18 anos, sendo que 16 eram filhos de hipertensos e 16 filhos de [...] normotensos. Para cada indivíduo foi aferida a PA basal seguida da aplicação de três testes pressóricos: teste do exercício isométrico com o handgrip, teste pressor ao frio e teste do exercício aritmético mental. Para a aferição da PA foi utilizado um dispositivo oscilométrico, digital, previamente calibrado. RESULTADOS: Os filhos de hipertensos exibiram valores basais de PA, tanto sistólica quanto diastólica, maiores que os filhos de normotensos (p Abstract in english PURPOSE: To compare cardiovascular reactivity in adolescents with and without family history of hypertension. METHODS: Thirty two subjects, males, students, aging between 13 to 18 years old were examined. One half of them had no family history of hypertension and the other half had at least one hype [...] rtensive parent. Basal blood pressure level was obtained before the application of the following selected tests: isometric handgrip exercise test, cold pressor test and arithmetic mental stress test. The blood pressure values were obtained by a digital, oscilometric device, previously calibrated. RESULTS: The subjects with family history of hypertension exhibited higher basal levels of both systolic and diastolic blood pressure (p

José Wilson S., Cavalcante; Leonardo P., Cavalcante; Walewska S., Pacheco; Marcus G. F. de, Menezes; Carlos G., Gama Fº.

1997-11-01

185

Sildenafil and diastolic dysfunction after acute myocardial infarction in patients with preserved ejection fraction : the Sildenafil and Diastolic Dysfunction After Acute Myocardial Infarction (SIDAMI) trial  

DEFF Research Database (Denmark)

Diastolic dysfunction is frequently seen after myocardial infarction and is characterized by a disproportionate increase in filling pressure during exercise to maintain stroke volume. We hypothesized that sildenafil would reduce filling pressure during exercise in patients with diastolic dysfunction after myocardial infarction.

Andersen, Mads J; ErsbØll, Mads

2013-01-01

186

Dietary sodium and arterial blood pressure: evidence against genetic susceptibility.  

OpenAIRE

Thirty five subjects with both parents in the top third of their age specific blood pressure distributions and 31 subjects with both parents in the bottom third of their blood pressure distributions restricted their intake of sodium for eight weeks while taking part in a double blind, randomised crossover trial of supplements of sodium and placebo. A comparison of two periods of four weeks at different intakes of sodium showed no differences in blood pressure in either the groups as a whole o...

Watt, G. C.; Foy, C. J.; Hart, J. T.; Bingham, G.; Edwards, C.; Hart, M.; Thomas, E.; Walton, P.

1985-01-01

187

Numerical simulation of blood flow and pressure drop in the pulmonary arterial and venous circulation.  

Science.gov (United States)

A novel multiscale mathematical and computational model of the pulmonary circulation is presented and used to analyse both arterial and venous pressure and flow. This work is a major advance over previous studies by Olufsen et al. (Ann Biomed Eng 28:1281-1299, 2012) which only considered the arterial circulation. For the first three generations of vessels within the pulmonary circulation, geometry is specified from patient-specific measurements obtained using magnetic resonance imaging (MRI). Blood flow and pressure in the larger arteries and veins are predicted using a nonlinear, cross-sectional-area-averaged system of equations for a Newtonian fluid in an elastic tube. Inflow into the main pulmonary artery is obtained from MRI measurements, while pressure entering the left atrium from the main pulmonary vein is kept constant at the normal mean value of 2 mmHg. Each terminal vessel in the network of 'large' arteries is connected to its corresponding terminal vein via a network of vessels representing the vascular bed of smaller arteries and veins. We develop and implement an algorithm to calculate the admittance of each vascular bed, using bifurcating structured trees and recursion. The structured-tree models take into account the geometry and material properties of the 'smaller' arteries and veins of radii ? 50 ?m. We study the effects on flow and pressure associated with three classes of pulmonary hypertension expressed via stiffening of larger and smaller vessels, and vascular rarefaction. The results of simulating these pathological conditions are in agreement with clinical observations, showing that the model has potential for assisting with diagnosis and treatment for circulatory diseases within the lung. PMID:24610385

Qureshi, M Umar; Vaughan, Gareth D A; Sainsbury, Christopher; Johnson, Martin; Peskin, Charles S; Olufsen, Mette S; Hill, N A

2014-10-01

188

Surgical and histopathological effects of topical Ankaferd hemostat on major arterial vessel injury related to elevated intra-arterial blood pressure  

OpenAIRE

Objective: The aim of this study was to assess the surgical and histopathological hemostatic effects of topical Ankaferd blood stopper (ABS) on major arterial vessel injury related to elevated intra-arterial blood pressure in an experimental rabbit model.Materials and Methods: The study included 14 New Zealand rabbits. ABS was used to treat femoral artery puncture on 1 side in each animal and the other untreated side served as the control. Likewise, for abdominal aortic puncture, only 50% of ...

Tulga Ulus, A.; Turan, Nilu?fer N.; Sertan Özyalç?n; Gülden Aydo?; Fatma Ulus; Hakan Göker; Haznedarog?lu, I?brahim C.

2011-01-01

189

Effects of an exercise program on blood pressure in patients with treated hypertension and chronic Chagas' heart disease / Efeitos de um programa de exercícios na pressão arterial de pacientes com hipertensão controlada e cardiopatia chagásica crônica  

Scientific Electronic Library Online (English)

Full Text Available INTRODUÇÃO: Estudos prévios descrevem um desequilíbrio do sistema nervoso autônomo na doença de Chagas causando maior atividade simpática, o que poderia influenciar na gênese da hipertensão arterial. No entanto, pacientes submetidos a exercícios físicos regulares poderiam contrapor esta condição, vi [...] sto que o exercício provoca respostas fisiológicas através de adaptações autonômicas e hemodinâmicas que influenciam positivamente o sistema cardiovascular. O presente estudo se propõe a avaliar os efeitos da reabilitação cardíaca sobre a pressão arterial em pacientes hipertensos com cardiopatia chagásica crônica. MÉTODOS: Foram recrutados 17 pacientes submetidos a um programa regular de exercícios durante 24 semanas, sendo utilizado monitorização ambulatorial da pressão arterial (MAPA) antes e após o treinamento. Foi descrita a diferença da pressão arterial sistólica (PAS), pressão arterial diastólica (PAD) e pressão arterial média (PAM) do início ao fim estudo. RESULTADOS: As pressões foram avaliadas de forma geral e nos períodos de vigília e sono, respectivamente: PAS (p=0,34; 0,23; 0,85), PAD (p=0,46; 0,44; 0,94) e PAM (p=0,41; 0,30; 0,97). CONCLUSÕES: Não houve diferença estatisticamente significativa na variação da pressão arterial após o período de reabilitação cardíaca de 24 semanas, no entanto, evidenciamos que o treinamento físico é seguro em pacientes com cardiopatia chagásica crônica, não ocorrendo aumento da pressão arterial. Abstract in english INTRODUCTION: Previous studies describe an imbalance of the autonomic nervous system in Chagas' disease causing increased sympathetic activity, which could influence the genesis of hypertension. However, patients undergoing regular physical exercise could counteract this condition, considering that [...] exercise causes physiological responses through autonomic and hemodynamic changes that positively affect the cardiovascular system. This study aimed to evaluate the effects of an exercise program on blood pressure in hypertensive patients with chronic Chagas' heart disease. METHODS: We recruited 17 patients to a 24-week regular exercise program and used ambulatory blood pressure monitoring before and after training. We determined the differences in the systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean blood pressure (MBP) from the beginning to the end of the study. RESULTS: The blood pressures were evaluated in general and during periods of wakefulness and sleep, respectively: SBP (p = 0.34; 0.23; 0.85), DBP (p = 0.46; 0.44; 0.94) and MBP (p = 0.41; 0.30; 0.97). CONCLUSIONS: There was no statistically significant change in blood pressure after the 24-week exercise program; however, we concluded that physical training is safe for patients with chronic Chagas' disease, with no incidence of increase in blood pressure.

Claudia Rosa de, Oliveira; Andréa Silvestre de, Sousa; Bráulio, Santos; Paloma Hargreaves, Fialho; Carla Cristiane Soares dos, Santos; Juliana Rega de, Oliveira; Marcus Vinícius, Souza.

2012-12-01

190

Comment on: Serum cholesterol and LDL-C in association with level of diastolic blood pressure in type 2 diabetic patients  

OpenAIRE

Implication for health policy/practice/research/medical education:Monitoring of blood pressure and serum lipids would be beneficial for diabetic patients in preventing the disease progression especially diabetic nephropathy in this population.

Nasri Hamid

2012-01-01

191

Metabólitos séricos da vitamina D não se correlacionam com pressão arterial em adolescentes There are no association between vitamin D metabolites and blood pressure in adolescents  

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Full Text Available OBJETIVO: O objetivo deste estudo foi avaliar a associação entre o estado nutricional da vitamina D, a adiposidade e a pressão arterial (PA em adolescentes. MÉTODOS: Foi realizada avaliação antropométrica, da composição corporal, da ingestão alimentar, de medidas bioquímicas e aferição da PA de 205 adolescentes, com média de idade de 18,2 anos. RESULTADOS: Destes, 12,19% apresentaram PA elevada. O nível sérico médio da 25OHD foi 29,2(0,8 ng/mL, e 62% dos adolescentes apresentaram insuficiência de vitamina D. Não foi encontrada correlação significativa entre a PAS e a PAD com a 25OHD e a 1,25(OH2D. Houve correlação negativa entre a PAD com os níveis séricos de adiponectina, e tanto a PAS quanto a PAD apresentaram correlação positiva com a circunferência da cintura em ambos os sexos. CONCLUSÃO: Não houve relação entre os níveis séricos de vitamina D e a PA. Porém, a gordura visceral apresenta risco potencial para elevação da PA em adolescentes.OBJETIVES: The purpose of this study was to evaluate the relationships between serum levels of vitamin D and blood pressure (BP in adolescents. METHODS: The anthropometric measurements, body composition, dietary intake, blood pressure and biochemical measurements was undertaken. RESULTS: Two hundred and five adolescents, 106 boys and 99 girls, mean aged 18.2 years old, participate of the study. Elevated BP was observed in 12.19% of the adolescents. Mean 25OHD concentration was 29.2(0.8 ng/mL. Vitamin D insufficiency was observed in 62% of adolescents. There were no correlation between systolic and diastolic BP with 25OHD and 1,25(OH2D concentration. An inverse correlation between adiponectin and diastolic BP was observed and positive significant correlation was observed between waist circumference with systolic and diastolic BP in both boys and in girls. In conclusion, no relationships between vitamin D levels and blood pressure were observed. CONCLUSION: However, the intra-abdominal adiposity offers potential risk to BP elevation in adolescents.

Barbara Santarosa Emo Peters

2009-06-01

192

Metabólitos séricos da vitamina D não se correlacionam com pressão arterial em adolescentes / There are no association between vitamin D metabolites and blood pressure in adolescents  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: O objetivo deste estudo foi avaliar a associação entre o estado nutricional da vitamina D, a adiposidade e a pressão arterial (PA) em adolescentes. MÉTODOS: Foi realizada avaliação antropométrica, da composição corporal, da ingestão alimentar, de medidas bioquímicas e aferição da PA de 205 [...] adolescentes, com média de idade de 18,2 anos. RESULTADOS: Destes, 12,19% apresentaram PA elevada. O nível sérico médio da 25OHD foi 29,2(0,8) ng/mL, e 62% dos adolescentes apresentaram insuficiência de vitamina D. Não foi encontrada correlação significativa entre a PAS e a PAD com a 25OHD e a 1,25(OH)2D. Houve correlação negativa entre a PAD com os níveis séricos de adiponectina, e tanto a PAS quanto a PAD apresentaram correlação positiva com a circunferência da cintura em ambos os sexos. CONCLUSÃO: Não houve relação entre os níveis séricos de vitamina D e a PA. Porém, a gordura visceral apresenta risco potencial para elevação da PA em adolescentes. Abstract in english OBJETIVES: The purpose of this study was to evaluate the relationships between serum levels of vitamin D and blood pressure (BP) in adolescents. METHODS: The anthropometric measurements, body composition, dietary intake, blood pressure and biochemical measurements was undertaken. RESULTS: Two hundre [...] d and five adolescents, 106 boys and 99 girls, mean aged 18.2 years old, participate of the study. Elevated BP was observed in 12.19% of the adolescents. Mean 25OHD concentration was 29.2(0.8) ng/mL. Vitamin D insufficiency was observed in 62% of adolescents. There were no correlation between systolic and diastolic BP with 25OHD and 1,25(OH)2D concentration. An inverse correlation between adiponectin and diastolic BP was observed and positive significant correlation was observed between waist circumference with systolic and diastolic BP in both boys and in girls. In conclusion, no relationships between vitamin D levels and blood pressure were observed. CONCLUSION: However, the intra-abdominal adiposity offers potential risk to BP elevation in adolescents.

Barbara Santarosa Emo, Peters; Janaína Pivetta, Roque; Mauro, Fisberg; Lígia Araújo, Martini.

2009-06-01

193

Ranolazine improves diastolic function in spontaneously hypertensive rats.  

Science.gov (United States)

Diastolic dysfunction can lead to heart failure with preserved ejection fraction, for which there is no effective therapeutic. Ranolazine has been reported to reduce diastolic dysfunction, but the specific mechanisms of action are unclear. The effect of ranolazine on diastolic function was examined in spontaneously hypertensive rats (SHRs), where left ventricular relaxation is impaired and stiffness increased. The objective of this study was to determine whether ranolazine improves diastolic function in SHRs and identify the mechanism(s) by which improvement is achieved. Specifically, to test the hypothesis that ranolazine, by inhibiting late sodium current, reduces Ca(2+) overload and promotes ventricular relaxation and reduction in diastolic stiffness, the effects of ranolazine or vehicle on heart function and the response to dobutamine challenge were evaluated in aged male SHRs and Wistar-Kyoto rats by echocardiography and pressure-volume loop analysis. The effects of ranolazine and the more specific sodium channel inhibitor tetrodotoxin were determined on the late sodium current, sarcomere length, and intracellular calcium in isolated cardiomyocytes. Ranolazine reduced the end-diastolic pressure-volume relationship slope and improved diastolic function during dobutamine challenge in the SHR. Ranolazine and tetrodotoxin also enhanced cardiomyocyte relaxation and reduced myoplasmic free Ca(2+) during diastole at high-stimulus rates in the SHR. The density of the late sodium current was elevated in SHRs. In conclusion, ranolazine was effective in reducing diastolic dysfunction in the SHR. Its mechanism of action, at least in part, is consistent with inhibition of the increased late sodium current in the SHR leading to reduced Ca(2+) overload. PMID:24464752

Williams, Sarah; Pourrier, Marc; McAfee, Donald; Lin, Shunping; Fedida, David

2014-03-01

194

Study the effect of exercise on systolic pulmonary artery pressure in healthy subjects  

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Full Text Available Introduction: As no data is available concerning the cut-off value defining abnormal pulmonary artery systolic pressure (PASP response in subjects of various ages, the aim of this study is to assess physiological PASP response to exercise in healthy individuals of various ages. Material and methods: One hundred and twenty three healthy volunteers, aged 30 to 70 years, underwent Doppler echocardiographic measurements at rest and after treadmill exercise test. Pulmonary artery systolic pressure was estimated at rest, and immediately after peak exercise using Bernoulli formula (four times tricuspid valve regurgitation velocity squared adding an estimated right atrial pressure. Results: Lower and upper limits of PASP during rest was 7 and 28 mmHg and after peak exercise was 14 and 48 mmHg respectively. After exercise, PASP increased from rest (14 ± 4 mmHg to peak (25 ± 7 mmHg. Pulmonary artery systolic pressure during rest and peak exercise, increased with age, but has no correlation with body mass index or gender. Conclusion: Pulmonary artery systolic pressure at peak exercise can frequently reach values ? 30 mmHg in healthy individuals with good exercise capacity, especially in elderly individuals, which goes beyond pathologic definitions of pulmonary hypertension.

Mohammad Nourizadeh

2012-04-01

195

Development of a tonometric sensor for measurement and recording of arterial pressure waveform  

Science.gov (United States)

There are many techniques and devices for measurement and recording of arterial blood pressure. Some of them allow (enable) additionally to observe the shape of a wave of arterial pressure, which can be regarded as one of the most important diagnostic parameters of human cardiovascular system. This paper presents a novel design and prototype of a new, non-invasive blood waveform measuring device. It expounds theoretical and experimental (including latest preliminary clinical) results obtained during several years of extensive investigations into blood pressure waveform measuring and monitoring problem. According to investigations performed in the laboratory and preliminary clinical evaluation, the sensor has linear steady-state characteristics and satisfactory dynamic properties. It is an efficient and accurate tool for blood pressure waveform monitoring and assessing the cardiovascular condition of the patients. The novelty of this solution is that the device is equipped with a pneumatic pressure sensor based on the pneumatic nozzle flapper amplifier principle with negative feedback. Due to such a technical solution, the device does not require any cuff, which remains an essential component of the majority of contemporary non-invasive blood pressure measurement devices; therefore, it can be used on the artery where the application of a cuff would be impossible (e.g., carotid artery). This advantage makes possible to obtain an accurate shape of blood pressure waveform with high fidelity, comparable to a direct measurement method. Moreover, during the measurement the device converts directly "pressure into pressure." Such a principle of operation makes possible to eliminate additional calibration (at the current stage of research we have eliminated the necessity of calibration in laboratory conditions).

Tomczuk, K.; Werszko, M.; Sasiadek, J. Z.; Kosek, J.; Berny, W.; Weiser, A.; Feder-Kubis, J.

2013-09-01

196

Avaliação de influências sociais e econômicas sobre a pressão arterial de adolescentes de escolas públicas e privadas: um estudo epidemiológico Assessment of social and economic influences on blood pressure of adolescents in public and private schools: an epidemiological study  

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Full Text Available INTRODUÇÃO: Anteriormente, a alta prevalência de hipertensão arterial em alunos do Ensino Médio de Sorocaba, em São Paulo, foi descrita. Neste estudo, em nova amostra de alunos da mesma faixa etária, oriundos de escolas públicas e privadas, foi avaliado se as diferenças socioeconômicas e o modo de vida podem influenciar os valores da pressão arterial. MÉTODOS: Trata-se de um estudo epidemiológico, inserido entre as atividades de um trabalho comunitário, em que estudantes de Medicina fazem palestras para alunos do Ensino Médio, objetivando estimular hábitos de vida saudáveis e a prevenção primária da hipertensão arterial. Em amostra aleatória de 410 alunos do segundo ano do Ensino Médio (209 de escolas públicas e 201 de escolas privadas, foram determinados o peso, a altura e a pressão arterial, e foi aplicado um questionário epidemiológico e socioeconômico. RESULTADOS: Não há diferenças estatísticas entre os alunos das escolas públicas e privadas quanto à distribuição de sexo, ao índice de massa corporal (IMC, à pressão arterial sistólica e diastólica, à prevalência de hipertensão arterial (16,3%, à porcentagem de fumantes (5,9%, à atividade física regular e aos antecedentes familiares de hipertensão arterial. Nas escolas públicas há maior porcentagem de afro-descendentes, os alunos trabalham fora de casa com maior frequência e têm menor renda familiar. Nas escolas públicas e privadas, os homens têm maior prevalência de hipertensão arterial e a média da pressão arterial é maior que nas mulheres. O IMC tem correlação positiva com a pressão arterial sistólica e diastólica. CONCLUSÕES: A hipertensão arterial e outros fatores de risco cardiovasculares têm início precoce e necessitam de intervenções educativas para a prevenção primária. Fatores socioeconômicos não influenciam a pressão arterial na adolescência.INTRODUCTION: The high prevalence of hypertension in high school students in Sorocaba, São Paulo, Brazil, has already been described. In this study, within a new sample of high school students from public and private schools, we evaluated if socioeconomic and lifestyle influence on blood pressure values. METHODS: This is an epidemiological study, which is part of the activities of a community-based work conducted by medical students. They give speeches to high school students aiming at stimulating a healthy lifestyle and primary prevention of hypertension. In a random sample of 410 students in junior high school (209 from public schools and 201 from private schools, we determined the weight, height, and blood pressure, furthermore, a questionnaire identifying epidemiological and socioeconomic status was applied. RESULTS: No statistical differences were found among students from public and private schools regarding the distribution of gender, body mass index (BMI, systolic and diastolic blood pressure, prevalence of hypertension (16.3%, percentage of smokers (5.9%, regular physical activity, and family history of hypertension. In public schools, there is a higher percentage of African descendents students and a higher percentage of students who also work due to low family income. Men from public and private schools have higher prevalence of hypertension, and their mean blood pressure is higher than in women. BMI has a positive correlation with systolic and diastolic blood pressure. CONCLUSIONS: Hypertension and other cardiovascular risk factors have an early beginning and require educational interventions for primary prevention. Socioeconomic factors do not affect blood pressure in adolescence.

Fernando Antonio de Almeida

2011-06-01

197

Noninvasive Ankle Blood Pressure Measurements by Oscillometry  

OpenAIRE

Noninvasive ankle systolic, mean and diastolic pressures were obtained with an oscillometric instrument available commercially. Systolic pressures were also measured at either the posterior tibial or dorsal pedal artery by using the Doppler technique with the ultrasound probe. Ankle pressures were obtained in normal subjects and in patients with peripheral vascular disease, particularly patients with calcified or incompressible vessels or with different posterior tibial and dorsal pedal Doppl...

Salles-cunha, Sergio X.; Vincent, Dennis G.; Towne, Jonathan B.; Bernhard, Victor M.

1982-01-01

198

Relationship between pulmonary artery volumes at computed tomography and pulmonary artery pressures in patients with- and without pulmonary hypertension  

International Nuclear Information System (INIS)

Objectives: This study was designed to determine the relationship between pulmonary artery (PA) volumes at computed tomography (CT) and PA pressures at right-sided heart catheterization in patients with and without pulmonary hypertension (PAH) to develop a noninvasive CT method of PA pressure quantification. Materials and methods: Sixteen patients with chronic sleep apnea syndrome underwent contrast enhanced helical CT (slice thickness 3 mm; pitch 2; increment 2 mm) at inspiration. Eight patients had PAH while cardiopulmonary disease has been excluded in eight other patients. Vascular volumes were determined using a 3D technique (threshold seeded vascular tracing algorithm; thresholds -600 H [lower] and 3000 H [upper]). Right-sided heart catheterization measurements were available for linear regression analysis of PA volumes and pressures. Results: Correlation between PA pressures and volumes (normalized for BMI), was high in both groups (without PAH: r = .85; with PAH .90, Pearson). Compared to elevated PA pressures in patients with pulmonary hypertension (p < .005), PA volumes also were significantly increased (p < .05) among the groups. Conclusions: High correlation was found between PA volumes and mean PA pressures in patients with- and without PAH. Significant differences in PA volumes at CT-volumetry may admit non-invasive determination of pulmonary hypertension

199

Relationship between pulmonary artery volumes at computed tomography and pulmonary artery pressures in patients with- and without pulmonary hypertension  

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Objectives: This study was designed to determine the relationship between pulmonary artery (PA) volumes at computed tomography (CT) and PA pressures at right-sided heart catheterization in patients with and without pulmonary hypertension (PAH) to develop a noninvasive CT method of PA pressure quantification. Materials and methods: Sixteen patients with chronic sleep apnea syndrome underwent contrast enhanced helical CT (slice thickness 3 mm; pitch 2; increment 2 mm) at inspiration. Eight patients had PAH while cardiopulmonary disease has been excluded in eight other patients. Vascular volumes were determined using a 3D technique (threshold seeded vascular tracing algorithm; thresholds -600 H [lower] and 3000 H [upper]). Right-sided heart catheterization measurements were available for linear regression analysis of PA volumes and pressures. Results: Correlation between PA pressures and volumes (normalized for BMI), was high in both groups (without PAH: r = .85; with PAH .90, Pearson). Compared to elevated PA pressures in patients with pulmonary hypertension (p < .005), PA volumes also were significantly increased (p < .05) among the groups. Conclusions: High correlation was found between PA volumes and mean PA pressures in patients with- and without PAH. Significant differences in PA volumes at CT-volumetry may admit non-invasive determination of pulmonary hypertension.

Froelich, Jens J. [Department of Radiology, Philipps-University Hospital, Baldingerstrasse, 35043 Marburg (Germany)], E-mail: jens.froelich@klinikum-hef.de; Koenig, Helmut [Department of Radiology, Philipps-University Hospital, Baldingerstrasse, 35043 Marburg (Germany)], E-mail: helmut.koenig@siemens.com; Knaak, Lennard [Department of Medicine, Philipps-University Hospital, Baldingerstrasse, 35043 Marburg (Germany)], E-mail: froehlic@staff.uni-marburg.de; Krass, Stefan [MeVis Research, Universitaetsallee 29, 28359 Bremen (Germany)], E-mail: krass@mevis.de; Klose, Klaus J. [Department of Radiology, Philipps-University Hospital, Baldingerstrasse, 35043 Marburg (Germany)], E-mail: klose@med.uni-marburg.de

2008-09-15

200

Cambios en la presión arterial en un grupo de voluntarios normotensos después del consumo de diferentes dosis de café filtrado Changes in blood pressure in a group of normotense volunteers after consumption or different doses of filtered coffee  

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Full Text Available No es clara la asociación entre el consumo de café y los cambios en los niveles de presión arterial; si bien algunos estudios muestran una correlación positiva, otros no logran confirmarla. El objetivo de este estudio fue determinar el cambio en los niveles de presión arterial en un grupo de voluntarios normotensos sometidos al consumo de diferentes dosis de café filtrado. Se trata de un estudio prospectivo, clínico controlado, en el cual se conformaron cuatro grupos y se sometieron por un período de seis semanas al consumo de diferentes cantidades de café filtrado: el grupo uno no consumió café, el grupo dos consumió 200 mL, el tres 400 mL y el cuatro 600 mL. Antes y al final de la intervención, en cada sujeto se midieron los niveles de presión arterial; en el grupo control se midió la concentración de cafeína antes, durante y al final de la intervención. Los resultados mostraron grupos comparables por género, edad e índice de masa corporal, sin diferencias significativas en las condiciones basales. Después de la intervención, la presión arterial sistólica y diastólica no mostró diferencia intragrupos, excepto en el grupo cuatro en el cual disminuyó significativamente (p=0,006 la presión arterial diastólica. Entre grupos los cambios en los niveles de presión sistólica y diastólica no fueron significativos (p=0,510 y 0,430 respectivamente. En conclusión, el consumo de diferentes dosis de café filtrado no ocasionó en sujetos normotensos cambios significativos en los niveles de presión arterial; el grupo que se abstuvo de tomar café no mostró disminución significativa de la presión arterial.The association between coffee consumption and changes in blood pressure values is not clear yet. Although some studies show a positive correlation, others fail to confirm it. The aim of this study was to determine changes in blood pressure values in a group of normotense volunteers submitted to consumption of different doses of filtered coffee. This is a prospective clinical controlled study in which four groups were conformed and were submitted during a period of six weeks to consumption of different doses of filtered coffee: group one did not have coffee, group two consumed 200 mL, group three 400 mL and group four 600 mL. Blood pressure values were measured before and at the end of the intervention in each subject; in the control group coffeine concentration was measured before, during and at the end of the intervention. The results showed comparable groups by gender, age and body mass index, without significant differences in basal conditions. After the intervention, systolic and diastolic blood pressure did not show any difference between the groups, with the exception of group four in which diastolic blood pressure diminished significantly (p=0.006. Between the groups, the changes in systolic and diastolic blood pressure values were not significant (p=0.510 and 0.430 respectively. In conclusion, consumption of different doses of filtered coffee did not cause significant changes in blood pressure values; the group that did not have coffee did not show significant lowering of blood pressure values.

Gloria M Agudelo

2008-12-01

201

Elevated Intraocular Pressure due to Arteriovenous Fistula between External Carotid Artery and Facial Vein.  

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Aqueous outflow via the conventional outflow pathway is dependent on the pressure gradient between intraocular pressure (IOP) and episcleral venous pressure (EVP). Elevated IOP resulting from increased EVP is a well-known complication of arteriovenous fistulas, which are usually between the carotid artery and the cavernous sinus. Arteriovenous malformations usually occur spontaneously, after a trauma or from iatrogenic causes, and they manifest with findings of chemosis, dilatation of the conjunctival vessels, exophthalmos, and extraocular motility limitation. In this study, we present a case of elevated IOP due to facial arteriovenous malformations following a functional neck dissection surgery that caused intraocular pressure elevation. PMID:25349756

Cagatay, Halil Huseyin; Ekinci, Metin; Sendul, Selam Yekta; Uslu, Ceylan; Demir, Mehmet; Ulusay, S?tk? Mert; Uysal, Ender; Seker, Selma

2014-01-01

202

Brachial artery vasomotion and transducer pressure effect on measurements by active contour segmentation on ultrasound  

International Nuclear Information System (INIS)

Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithm's performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging

203

Brachial artery vasomotion and transducer pressure effect on measurements by active contour segmentation on ultrasound  

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Purpose: To use feed-forward active contours (snakes) to track and measure brachial artery vasomotion on ultrasound images recorded in both transverse and longitudinal views; and to compare the algorithm's performance in each view. Methods: Longitudinal and transverse view ultrasound image sequences of 45 brachial arteries were segmented by feed-forward active contour (FFAC). The segmented regions were used to measure vasomotion artery diameter, cross-sectional area, and distention both as peak-to-peak diameter and as area. ECG waveforms were also simultaneously extracted frame-by-frame by thresholding a running finite-difference image between consecutive images. The arterial and ECG waveforms were compared as they traced each phase of the cardiac cycle. Results: FFAC successfully segmented arteries in longitudinal and transverse views in all 45 cases. The automated analysis took significantly less time than manual tracing, but produced superior, well-behaved arterial waveforms. Automated arterial measurements also had lower interobserver variability as measured by correlation, difference in mean values, and coefficient of variation. Although FFAC successfully segmented both the longitudinal and transverse images, transverse measurements were less variable. The cross-sectional area computed from the longitudinal images was 27% lower than the area measured from transverse images, possibly due to the compression of the artery along the image depth by transducer pressure. Conclusions: FFAC is a robust and sensitive vasomotion segmentation algorithm in both transverse and longitudinal views. Transverse imaging may offer advantages over longitudinal imaging: transverse measurements are more consistent, possibly because the method is less sensitive to variations in transducer pressure during imaging.

Cary, Theodore W.; Sultan, Laith R.; Sehgal, Chandra M., E-mail: sehgalc@uphs.upenn.edu [Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Reamer, Courtney B.; Mohler, Emile R. [Department of Medicine, Division of Cardiovascular Medicine, Section of Vascular Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2014-02-15

204

Pulmonary artery pressure responses to increased cardiac output in chickens with raised metabolic rate  

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Previous work has shown remarkable differences in the pressure-flow relations of the pulmonary circulation between birds and mammals. For example several studies suggest that the avian pulmonary blood vessels behave like rigid tubes, very different from the situation in mammalian lung. We therefore speculated that birds would develop high pulmonary artery pressures when the cardiac output was substantially increased during heavy exercise, for example during flight. However because of the tech...

West, John B.; Fu, Zhenxing; Gu, Yusu; Wagner, Harrieth E.; Carr, J. Austin; Peterson, Kirk L.

2010-01-01

205

Fatores preditores para o óbito neonatal em gestações com diástole zero ou reversa na doplervelocimetria da artéria umbilical / Predictor parameters of neonatal death in gestations with absent or reverse end-diastolic flow in the umbilical artery doppler velocimetry  

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Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: avaliar os fatores de risco antenatais e pós-natais para o óbito neonatal em gestações com diástole zero (DZ) ou reversa (DR) na doplervelocimetria da artéria umbilical. MÉTODOS: estudo transversal, retrospectivo, inferencial, a partir de 48 prontuários de gestações únicas com DZ ou DR, id [...] ade gestacional entre 24 e 34 semanas, em uma maternidade no Nordeste do Brasil. A média de idade foi de 27,3 anos (DP: 7,9). Vinte (41,7%) eram primigestas. Síndromes hipertensivas foram observadas em 44 (91,7%) casos. Trinta e cinco (72,9%) apresentavam DZ e 13 (27,1%) DR. Procedeu-se inicialmente à análise univariada (teste t de Student e teste Exato de Fisher), relacionando os parâmetros com o desfecho avaliado (óbito neonatal). As variáveis que apresentaram associação significativa foram incluídas no modelo de regressão logística (Estatística de Wald). O nível de significância utilizado foi de 5%. RESULTADOS: a mortalidade perinatal foi de 64,6% (31/48). Ocorreram cinco óbitos fetais e 26 neonatais. A média de idade gestacional no momento do diagnóstico foi de 27,9 (DP: 2,8) semanas. A resolução da gestação antes de 24 horas após o diagnóstico ocorreu em 52,1% dos casos. Parto abdominal foi realizado em 85,4% dos casos. Os recém-nascidos pesaram em média 975,9 g (DP: 457,5). Vinte e quatro (57,1%) apresentaram Apgar menor que 7 no primeiro minuto e 21,4%, no quinto. A idade gestacional no momento do diagnóstico, o peso ao nascer e o Apgar de primeiro minuto revelaram-se variáveis significativamente relacionadas com o óbito neonatal (valores de p foram, respectivamente, 0,008; 0,004 e 0,020). As razões de chance foi de 6,6; 25,3 e 13,8 para o óbito neonatal, quando o diagnóstico foi estabelecido até a 28ª semana, peso Abstract in english PURPOSE: to evaluate the antenatal and postnatal risk factors of neonatal death in pregnancies with absent (DZ) or reverse (DR) end-diastolic flow in the umbilical artery. METHODS: a cross-sectional retrospective study based on data from 48 medical records of singleton pregnancies with DZ or DR, and [...] gestational age of 24 to 34 weeks, at a maternity in the Brazilian Northeast. Mean age was 27.3 (SD: 7.9) years. Twenty (41.7%) patients were primiparas. Hypertensive disorders were found in 44 (91.7%) cases. Thirty-five women (72.9%) had DZ and 13 (27.1%) had DR. Univariate analysis was firstly done (Student's t-test and Fisher's exact test) correlating the parameters with the assessed outcome (neonatal death). Variables that showed significant association were included in the logistic regression model (Wald statistics). The level of significance was set at 5%. RESULTS: The perinatal mortality rate was 64.6% (31/48). There were five stillbirths and 26 neonatal deaths. The mean gestational age at diagnosis was 27.9 (SD: 2.8) weeks. Deliveries before 24 hours after diagnosis occurred in 52.1% of the cases. Cesarean section was performed in 85.4% of the sample. The newborns weighed 975.9 g on average (SD: 457.5). Twenty-four (57.1%) presented Apgar scores below 7 in the first minute and 21.4% in the fifth minute. Gestational age at diagnosis, birth weight and Apgar of the first minute proved to be variables significantly related to neonatal death (p values were: 0.008, 0.004, and 0.020, respectively). The Odds Ratio was 6.6, 25.3 and 13.8 for neonatal death, when the diagnosis was established at the 28th week, weight was

Manoel, Martins Neto; Francisco Herlânio Costa, Carvalho; Rosa Maria Salani, Mota; Carlos Augusto, Alencar Júnior.

2010-07-01

206

El curso de la hemodiálisis está asociado a cambios en el umbral de dolor y en las relaciones entre presión arterial y dolor / Haemodialysis course is associated to changes in pain threshold and in the relations between arterial pressure and pain  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Antecedentes: La presión arterial se asocia negativamente con la percepción del dolor. Objetivos: En este estudio se comparan el dolor y las relaciones entre presión arterial y umbral doloroso al inicio y final de la hemodiálisis. Métodos: 14 pacientes con trastorno renal crónico bajo diálisis parti [...] ciparon en el estudio. Los umbrales de dolor fueron evaluados mediante algometría de presión de forma bilateral en dos puntos «gatillo»: la segunda costilla y la rodilla. La presión arterial y los umbrales de dolor se evaluaron: 1) 15 minutos después del inicio de la diálisis, y 2) 30 minutos antes de su final. Resultados: La presión arterial no cambió significativamente durante la diálisis. Se observó una disminución significativa del umbral de dolor en la segunda costilla izquierda y en la rodilla izquierda y derecha desde el inicio al final de la hemodiálisis. Al inicio de la diálisis no se obtuvieron correlaciones significativas entre presión arterial y dolor, mientras que al final de la diálisis la presión arterial se correlacionó positivamente con los umbrales de dolor (rs entre 0,552 y 0,806). Conclusiones: La hemodiálisis se asocia a cambios en la sensibilidad al dolor y en las relaciones entre presión arterial y dolor, y sugiere una modificación en el mecanismo de inhibición aferente del dolor originado a nivel cardiovascular. Como posibles explicaciones de este efecto se discuten los cambios que produce la hemodiálisis en las funciones cognitivo-perceptivas, en la regulación autonómica cardiovascular y en la habituación de variables relacionadas con el estrés. Abstract in english Antecedents: Arterial pressure is negatively associated to pain perception. Objectives: In this study, pain and the relations between arterial pressure and pain threshold were compared at the beginning and end of the heamodialysis. Methods: 14 patients with chronic renal disease participated in the [...] study. Pain thresholds were evaluated with pressure algometry bilaterally at two tender points: the second rib and the knee. Arterial pressure and pain thresholds were assessed twice: 1) 15 min alter dialysis onset and 2) 30 min before dialysis ended. Results: Arterial pressure remains unchanged through the dialysis. The course of dialysis was associated to a decrease in pain threshold in the second left rib and left and right knees. At the beginning of dialysis arterial pressure were uncorrelated with pain, while at the end of the dialysis both systolic and diastolic arterial pressure were strongly associated to pain thresholds (rs between 0.552 and 0.806): increased arterial pressure was associated to lower pain in terms of increased threshold. Conclusions: Heamodialysis is associated to changes in pain sensitivity and in the relationships between arterial pressure and pain, suggesting a modification in the ascending pain inhibition system arising from the cardiovascular system. Possible explanations of this effect include the changes produced by heamodialysis in cognitive-perceptive functions, in autonomic cardiovascular regulation, and in the habituation of stress-related variables.

G.A., Reyes del Paso; C.M., Perales Montilla.

207

Noninvasive arterial blood pressure waveform monitoring using two- element ultrasound system.  

Science.gov (United States)

This work details noninvasive arterial blood pressure (ABP) waveform estimation based on an arterial vessel cross-sectional area measurement combined with an elasticity measurement of the vessel, represented by pulse wave velocity (PWV), using a two-element ultrasound system. The overall ABP waveform estimation is validated in a custom-designed experimental setup mimicking the heart and an arterial vessel segment with two single element transducers, assuming a constant hemodynamic system. The estimation of local PWV using the flow-area method produces unbiased elasticity estimation of the tube in a pressure waveform comparison. The measured PWV using 16 cardiac cycles of data is 8.47 + 0.63 m/s with an associated scaling error of -1.56 + 14.0% in a direct pressure waveform comparison, showing negligible bias error on average. The distension waveform obtained from a complex cross-correlation model estimator (C3M) reliably traces small pressure changes reflected by the diameter change. The excellent agreement of an estimated pressure waveform to the reference pressure waveform suggests the promising potential of a readily available, inexpensive, and portable ABP waveform monitoring device. PMID:25881355

Seo, Joohyun; Pietrangelo, Sabino J; Lee, Hae-Seung; Sodini, Charles G

2015-04-01

208

Acute nitric oxide synthase inhibition and endothelin-1-dependent arterial pressure elevation  

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Full Text Available Key evidence that endogenous nitric oxide (NO inhibits the continuous, endothelin (ET-1-mediated drive to elevate arterial pressure includes demonstrations that ET-1 mediates a significant component of the pressure elevated by acute exposure to NO synthase (NOS inhibitors. This review examines the characteristics of this pressure elevation in order to elucidate potential mechanisms associated with the negative regulation of ET-1 by NO and, thereby, provide potential insight into the vascular pathophysiology underlying NO dysregulation. We surmise that the magnitude of the ET-1-dependent component of the NOS inhibitor-elevated pressure is 1 independent of underlying arterial pressure and other pressor pathways activated by the NOS inhibitors and 2 dependent on relatively higher NOS inhibitor dose, release of stored and de novo synthesized ET-1, and ETA receptor-mediated increased vascular resistance. Major implications of these conclusions include: 1 the marked variation of the ET-1-dependent component, i.e., from 0-100% of the pressure elevation, reflects the NO-ET-1 regulatory pathway. Thus, NOS inhibitor-mediated, ET-1-dependent pressure elevation in vascular pathophysiologies is an indicator of the level of compromised/enhanced function of this pathway; 2 NO is a more potent inhibitor of ET-1-mediated elevated arterial pressure than other pressor pathways, due in part to inhibition of intravascular pressure-independent release of ET-1. Thus, the ET-1-dependent component of pressure elevation in vascular pathophysiologies associated with NO dysregulation is of greater magnitude at higher levels of compromised NO.

RobertRapoport

2014-04-01

209

Endogenous Melanocortin System Activity Contributes to the Elevated Arterial Pressure in Spontaneously Hypertensive Rats  

Science.gov (United States)

Previous studies suggest that activation of the CNS melanocortin system reduces appetite while increasing sympathetic activity and arterial pressure. The present study tested whether endogenous activity of the CNS melanocortin 3/4 receptors (MC3/4-R) contributes to elevated arterial pressure in the spontaneously hypertensive rat (SHR), a model of hypertension with increased sympathetic activity. A cannula was placed in the lateral ventricle of male SHR and Wistar (WKY) rats for chronic intracerebroventricular (ICV) infusions (0.5 ?L/h). Mean arterial pressure (MAP) and heart rate (HR) were recorded 24 hour/d using telemetry. After 5-day control period, rats were infused with MC3/4-R antagonist (SHU-9119, 1 nmol/h-ICV) for 12 days, followed by 5-day posttreatment period. MC3/4-R antagonism increased food intake in SHR by 90% and in WKY by 125%, resulting in marked weight gain, insulin resistance, and hyperleptinemia in SHR and WKY. Despite weight gain, MC3/4-R antagonism reduced HR in SHR and WKY (?40 bpm), while lowering MAP to a greater extent in SHR (?22±4 mm Hg) than WKY (?4±3 mm Hg). SHU9119 treatment failed to cause further reductions in MAP during chronic adrenergic blockade with propranolol and terazosin. These results suggest that endogenous activity of the CNS melanocortin system contributes to the maintenance of adrenergic tone and elevated arterial pressure in SHR even though mRNA levels for POMC and MC4R in the mediobasal hypothalamus were not increased compared to WKY. These results also support the hypothesis that weight gain does not raise arterial pressure in the absence of a functional MC3/4-R. PMID:18285617

da Silva, Alexandre A.; do Carmo, Jussara M.; Kanyicska, Bela; Dubinion, John; Brandon, Elizabeth; Hall, John E.

2009-01-01

210

Limitação funcional e claudicação intermitente: impacto das medidas de pressão arterial / Functional limitation and intermittent claudication: impact of blood pressure measurements  

Scientific Electronic Library Online (English)

Full Text Available FUNDAMENTO: A hipertensão arterial é importante fator de risco para Doença Arterial Obstrutiva Periférica dos Membros Inferiores (DAOMI). Entretanto, a correlação entre pressão arterial e Pressão de Pulso (PP) com a gravidade da DAOMI e o prejuízo funcional decorrente dessa doença ainda não está bem [...] estabelecida na população brasileira. OBJETIVO: Verificar se há correlação entre pressão arterial, PP, gravidade da DAOMI e capacidade funcional de pacientes com DAOMI sintomática. MÉTODOS: FORAM avaliados 65 pacientes (62,2 ± 8,1 anos; 56,9% do sexo masculino), divididos em dois grupos: pressão arterial normal (A) e elevada (B). A gravidade da DAOMI foi avaliada por meio do Índice Tornozelo-Braquial (ITB) e a capacidade funcional, pelas distâncias total e livre de dor percorridas em teste de marcha. RESULTADOS: O grupo A foi constituído por 17 (26,1%) pacientes. A Pressão Arterial Sistólica (PAS), diastólica e a PP foram, respectivamente, 125,4 ± 11,7; 74,5 ± 9,1 e 50,9 ±10,0 mmHg, para o grupo A, e 160,7 ± 19,6; 90,0 ± 12,2 e 70,7 ± 20,2 mmHg, para o grupo B. O ITB foi significativamente menor no grupo B (0,66 ± 0,12 vs 0,57 ± 0,13, p 40 mmHg percorreram menores distâncias. CONCLUSÃO: A PAS e a PP correlacionaram-se de forma significativa com as distâncias percorridas em teste de marcha, sugerindo que sejam marcardores clínicos da limitação da capacidade funcional em pacientes com DAOMI sintomática. Abstract in english BACKGROUND: Arterial hypertension is an important risk factor for Lower-Limb Occlusive Arterial Disease (LLOAD). However, the correlation between blood pressure and pulse pressure (PP) with LLOAD severity and functional impairment resulting from this disease is not well established in the Brazilian [...] population. OBJECTIVE: To verify whether there is a correlation between blood pressure, PP, LLOAD severity and functional capacity in patients with symptomatic LLOAD. METHODS: A total of 65 patients (62.2 + 8.1 years, 56.9% males) were evaluated. They were divided into two groups: normal (A) and high (B) blood pressure. LLOAD severity was assessed using the ankle-brachial index (ABI) and functional capacity by the total and pain-free walking distance at the 6-minute walking test (6MWT). RESULTS: Group A consisted of 17 (26.1%) patients. The systolic (SBP), diastolic blood pressure (DBP), and PP were, respectively, 125.4 ±11.7, 74.5 ± 9.1 and 50.9 ± 10.0 mmHg in group A and 160.7 ± 19.6, 90.0 ± 12.2 and 70.7 ± 20.2 mmHg in group B. The ABI was significantly lower in group B (0.66 ± 0.12 vs. 0.57 ± 0.13, p 40 mmHg walked shorter distances. CONCLUSION: SBP and PP significantly correlated with the distances walked in the 6MWT, suggesting they are clinical markers of functional capacity impairment in patients with symptomatic LLOAD.

Rita de Cássia Gengo e, Silva; Cassiana Rosa Galvão, Giribela; Nelson, Wolosker; Fernanda Marciano, Consolim-Colombo.

2012-02-01

211

Limitação funcional e claudicação intermitente: impacto das medidas de pressão arterial Functional limitation and intermittent claudication: impact of blood pressure measurements  

Directory of Open Access Journals (Sweden)

Full Text Available FUNDAMENTO: A hipertensão arterial é importante fator de risco para Doença Arterial Obstrutiva Periférica dos Membros Inferiores (DAOMI. Entretanto, a correlação entre pressão arterial e Pressão de Pulso (PP com a gravidade da DAOMI e o prejuízo funcional decorrente dessa doença ainda não está bem estabelecida na população brasileira. OBJETIVO: Verificar se há correlação entre pressão arterial, PP, gravidade da DAOMI e capacidade funcional de pacientes com DAOMI sintomática. MÉTODOS: FORAM avaliados 65 pacientes (62,2 ± 8,1 anos; 56,9% do sexo masculino, divididos em dois grupos: pressão arterial normal (A e elevada (B. A gravidade da DAOMI foi avaliada por meio do Índice Tornozelo-Braquial (ITB e a capacidade funcional, pelas distâncias total e livre de dor percorridas em teste de marcha. RESULTADOS: O grupo A foi constituído por 17 (26,1% pacientes. A Pressão Arterial Sistólica (PAS, diastólica e a PP foram, respectivamente, 125,4 ± 11,7; 74,5 ± 9,1 e 50,9 ±10,0 mmHg, para o grupo A, e 160,7 ± 19,6; 90,0 ± 12,2 e 70,7 ± 20,2 mmHg, para o grupo B. O ITB foi significativamente menor no grupo B (0,66 ± 0,12 vs 0,57 ± 0,13, p 40 mmHg percorreram menores distâncias. CONCLUSÃO: A PAS e a PP correlacionaram-se de forma significativa com as distâncias percorridas em teste de marcha, sugerindo que sejam marcardores clínicos da limitação da capacidade funcional em pacientes com DAOMI sintomática.BACKGROUND: Arterial hypertension is an important risk factor for Lower-Limb Occlusive Arterial Disease (LLOAD. However, the correlation between blood pressure and pulse pressure (PP with LLOAD severity and functional impairment resulting from this disease is not well established in the Brazilian population. OBJECTIVE: To verify whether there is a correlation between blood pressure, PP, LLOAD severity and functional capacity in patients with symptomatic LLOAD. METHODS: A total of 65 patients (62.2 + 8.1 years, 56.9% males were evaluated. They were divided into two groups: normal (A and high (B blood pressure. LLOAD severity was assessed using the ankle-brachial index (ABI and functional capacity by the total and pain-free walking distance at the 6-minute walking test (6MWT. RESULTS: Group A consisted of 17 (26.1% patients. The systolic (SBP, diastolic blood pressure (DBP, and PP were, respectively, 125.4 ±11.7, 74.5 ± 9.1 and 50.9 ± 10.0 mmHg in group A and 160.7 ± 19.6, 90.0 ± 12.2 and 70.7 ± 20.2 mmHg in group B. The ABI was significantly lower in group B (0.66 ± 0.12 vs. 0.57 ± 0.13, p 40 mmHg walked shorter distances. CONCLUSION: SBP and PP significantly correlated with the distances walked in the 6MWT, suggesting they are clinical markers of functional capacity impairment in patients with symptomatic LLOAD.

Rita de Cássia Gengo e Silva

2012-02-01

212

Resposta da pressão arterial ao esforço em adolescentes: influência do sobrepeso e obesidade / Blood pressure response to physical exertion in adolescents: influence of overweight and obesity  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese FUNDAMENTO: A resposta aguda da pressão arterial ao esforço tem sido utilizada como indicador de risco para o desenvolvimento de hipertensão arterial. Os fatores associados com essa resposta precisam ser esclarecidos a fim de se intervir na prevenção da doença hipertensiva. OBJETIVO: Descrever o com [...] portamento das variáveis cardiovasculares ao esforço agudo em adolescentes com excesso de peso, por meio de teste cardiopulmonar. MÉTODOS: A amostra foi constituída de 104 adolescentes (56 meninos e 48 meninas), divididos nos grupos de sobrepeso/obesos (GSO) e eutróficos (GE). Foram aferidas variáveis antropométricas (peso, estatura e IMC), de composição corporal (dobra cutânea) e variáveis hemodinâmicas de pressão arterial sistólica (PAS) e diastólica (PAD) e freqüência cardíaca (FC), no repouso e no esforço máximo do teste cardiopulmonar. RESULTADOS: No grupo masculino, identificaram-se maiores valores de pressão arterial sistólica de repouso para o GSO, quando comparados com o GE (113 ± 13 vs 106 ± 8 mmHg; p = 0,009), a PAS pré-exercício (120 ± 14 vs 109 ± 10 mmHg; p = 0,003) e de PAS na carga máxima de trabalho (156 ± 20 vs 146 ± 14 mmHg; p = 0,03). No grupo feminino, apenas a PAS pré-exercício foi superior no grupo de sobrepeso, quando isso foi comparado com as eutróficas (114 ± 11 vs 106 ± 10 mmHg; p = 0,009). CONCLUSÃO: A resposta pressórica durante o exercício foi mais exacerbada em adolescentes obesos quando comparada com àquela obtida em eutróficos, o que indica maior reatividade ao estresse físico. Abstract in english BACKGROUND: The acute blood pressure response to physical exertion has been used as an indicator of the risk of developing hypertension. The factors associated with this response need to be clarified for timely intervention in preventing hypertensive disease. OBJECTIVE: To describe the response of c [...] ardiovascular variables to acute physical exertion in overweight adolescents using cardiopulmonary exercise testing. METHODS: The sample consisted of 104 adolescents (56 boys and 48 girls), divided into two groups: the obese/overweight group (OOG) and the eutrophic group (EG). The following variables were measured: anthropometric (weight, height, and BMI), body composition (skin fold thickness), as well as hemodynamic variables such as systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and heart rate (HR), at rest and at maximal physical exertion during the cardiopulmonary test. RESULTS: In the male group, the greatest values of systolic arterial pressure at rest were recorded in the OOG as compared to the EG (113 ± 13 vs 106 ± 8 mmHg; p = 0.009), pre-exertion SAP (120 ± 14 vs 109 ± 10 mmHg; p = 0.003), and SAP during maximal exertion conditions (156 ± 20 vs 146 ± 14 mmHg; p = 0.03). In the female group, only pre-exertion SAP was higher in the overweight group as compared to the eutrophic girls (114 ± 11 vs 106 ± 10 mmHg; p = 0.009). CONCLUSION: The response of arterial blood pressure during physical exercise was most exacerbated in obese adolescents as compared to eutrophic teens, suggesting greater reactivity to physical exertion.

Luciana, Carletti; Anabel Nunes, Rodrigues; Anselmo José, Perez; Dalton Valentim, Vassallo.

2008-07-01

213

Skin perfusion pressure measured with a photo sensor in an air-filled plastic balloon: validity and reproducibility on the lower leg in normal subjects and patients suspected of obliterative arterial disease  

DEFF Research Database (Denmark)

An inflatable small plastic bag including a photo sensor was constructed for measurement of skin perfusion pressure avoiding the rim of the photo sensor over bony and tendineous surfaces of the tibia below the knee, at the ankle, and on the dorsal forefoot. Compression was obtained using a conical blood pressure cuff with continuous decrease from suprasystolic arm pressure. The validity of skin perfusion pressure with the new device was compared to that of isotope washout below the knee in normal subjects and in patients with an ischemic forefoot with acceptable agreement. The method had a high reproducibility within and between days in normal subjects. Compared to systolic arterial pressure measured using a strain gauge with a cuff on the ankle in normal subjects and patients with intermittent claudication the new device showed blood pressure in the skin closer to the diastolic pressure. The new pressure device thus had acceptable validity and reproducibility for estimation of the skin perfusion pressure andcan be used on bony and tendineous sites on the lower limb in regions where critical wound healing is frequent, e.g. ankle and forefoot.

Nielsen, Steen Levin; Nielsen, Anne Lerberg

2011-01-01

214

Cardiac output in idiopathic normal pressure hydrocephalus: association with arterial blood pressure and intracranial pressure wave amplitudes and outcome of shunt surgery  

OpenAIRE

Abstract Background In patients with idiopathic normal pressure hydrocephalus (iNPH) responding to shunt surgery, we have consistently found elevated intracranial pressure (ICP) wave amplitudes during diagnostic ICP monitoring prior to surgery. It remains unknown why ICP wave amplitudes are increased in these patients. Since iNPH is accompanied by a high incidence of vascular co-morbidity, a possible explanation is that there is reduced vascular compliance accompanied by elevated arterial blo...

Eide Per K

2011-01-01

215

Support of arterial blood pressure by major pressor systems in conscious dogs.  

Science.gov (United States)

The roles of the autonomic nervous system, vasopressin, and angiotensin II in support of blood pressure were evaluated in seven conscious, resting dogs while hydrated or dehydrated. Mean arterial blood pressure (MAP) was monitored, and the dogs were given hexamethonium to block autonomic ganglia. Thirty minutes later, they were given captopril, and after another 30 min, a vasopressin V1 antagonist, d(CH2)5TyrMeAVP, was given. The order okf administration of captopril and d(CH2)5TyrMeAVP was alternated in different experiments. Hexamethonium had no effect on steady-state MAP in either hydrated or dehydrated dogs. In hydrated dogs, the average MAP was 100 mmHg; d(CH2)5TyrMeAVP decreased MAP by approximately 12 mmHg, and captopril decreased MAP by 24 mmHg. The magnitude of the effect of these two inhibitors was independent of the order of their administration. Dehydration doubled the effect of d(CH2)5TyrMeAVP on MAP but had no effect on the response to captopril. The results suggest that 1) autonomic function is not essential for maintenance of arterial blood pressure in resting dogs; 2) during autonomic ganglionic blockade, arterial blood pressure is supported by both angiotensin II and vasopressin; and 3) dehydration increases the role of vasopressin in control of blood pressure. PMID:2901232

Brand, P H; Metting, P J; Britton, S L

1988-09-01

216

Fast and accurate pressure-drop prediction in straightened atherosclerotic coronary arteries.  

Science.gov (United States)

Atherosclerotic disease progression in coronary arteries is influenced by wall shear stress. To compute patient-specific wall shear stress, computational fluid dynamics (CFD) is required. In this study we propose a method for computing the pressure-drop in regions proximal and distal to a plaque, which can serve as a boundary condition in CFD. As a first step towards exploring the proposed method we investigated ten straightened coronary arteries. First, the flow fields were calculated with CFD and velocity profiles were fitted on the results. Second, the Navier-Stokes equation was simplified and solved with the found velocity profiles to obtain a pressure-drop estimate (?p (1)). Next, ?p (1) was compared to the pressure-drop from CFD (?p CFD) as a validation step. Finally, the velocity profiles, and thus the pressure-drop were predicted based on geometry and flow, resulting in ?p geom. We found that ?p (1) adequately estimated ?p CFD with velocity profiles that have one free parameter ?. This ? was successfully related to geometry and flow, resulting in an excellent agreement between ?p CFD and ?p geom: 3.9 ± 4.9% difference at Re = 150. We showed that this method can quickly and accurately predict pressure-drop on the basis of geometry and flow in straightened coronary arteries that are mildly diseased. PMID:25113232

Schrauwen, Jelle T C; Koeze, Dion J; Wentzel, Jolanda J; van de Vosse, Frans N; van der Steen, Anton F W; Gijsen, Frank J H

2015-01-01

217

Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion  

International Nuclear Information System (INIS)

Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO2) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO2) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detecheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO2 sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures. Both pulse oximeters showed gradual decrease of saturations during induced hypoperfusion which demonstrate the direct relation between blood volumes (PPG amplitudes), arterial vessel stenosis and blood oxygen saturation. The custom made pulse oximeter was found to be more sensitive to SpO2 changes than the commercial pulse oximeter especially at high occluding pressures

218

[Microproteinuria and circadian rhythm of blood pressure in patients with arterial hypertension].  

Science.gov (United States)

Microproteinuria is a recognized sign of early nephropathy in the course of arterial hypertension. There is few data concerning the excretion of proteins other than albumin in this group of patients. The aim of the study was to examine circadian rhythm of alfa-l-microglobulin (AlMG), albumin (ALB), immunoglobulin G (IgG) excretion and N-acetyl-beta-glukosaminidase (beta NAG)-activity, then to compare the results with the results of 24 hour ambulatory monitoring of arterial blood pressure in patients with arterial hypertension. The study comprised 28 patients. The control group included 27 healthy volunteers. Albumin concentration was determined by Beckman ICS2 nephelometer, using Beckman and Dako reagents. Blood pressure and ECG were monitored by analysis with ABP-system (AMP-USA). In patients with arterial hypertension significantly higher levels of ALB, AlMG, IgG and increased beta NAG activity were observed in morning urine samples. Despite hypotensive treatment blood pressure values were slightly, though significantly higher than in the control group. Among patients in the study circadian BP rhythm was disturbed. The results obtained suggest that in this group of patients subclinical nephropathy develops involving renal glomeruli and proximal tubules--probably resulting from vascular and humoral disorders, with accompanied hypertension. PMID:8677191

Marczewski, K; Krawczyk, W; Grzywna, R; Rózyc, P; Jarosz, M; Raszewski, G; Klimek, K

1996-01-01

219

Comparação entre os valores da pressão arterial central e braquial de pacientes com hipertensão arterial submetidos à cineangiocoronariografia / Comparison between the central and brachial blood pressure values in patients with hypertension undergoing cineangiocoronarography  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Languages: English, Portuguese Abstract in portuguese INTRODUÇÃO: Durante o envelhecimento, a pressão arterial sistólica (PS) e a pressão de pulso (PP) se elevam gradativamente, consequente à redução da elasticidade arterial. A medida da pressão arterial sistêmica (PAS) aferida na raiz da aorta tem sido considerada como um determinante independente da [...] mortalidade cardiovascular superior aos valores PAS braquial. OBJETIVO: Comparar os valores da PAS central e PAS braquial em portadores de hipertensão arterial nas diversas faixas etárias. MÉTODO: Avaliamos a PAS central na raiz da aorta e a PAS braquial no braço esquerdo pelo método oscilométrico em 244 pacientes com hipertensão submetidos à cineangiocoronariografia. Foram constituídos cinco grupos de pacientes: Grupo I, 39-49 anos, n = 36; Grupo II, 50-59 anos, n = 67; Grupo III, 60-69 anos, n = 69; Grupo IV, 70-79 anos, n = 46; e o Grupo V, > 80 anos, n = 26. RESULTADOS: Ao comparar a PS central versus PS braquial, foi possível encontrar significância a partir dos 50 anos de vida. Não encontramos diferença estatística entre a pressão diastólica central versus diastólica braquial, exceto nos pacientes com idade entre 60-69 anos. Na comparação entre a PP central e PP braquial, observamos que a PP central foi significativamente maior (entre 11 a 15 mmHg) em todos os pacientes com idade superior a 50 anos. CONCLUSÃO: Com o envelhecimento, os valores das PS e de PP, aferidas diretamente na raiz da aorta, são superiores àqueles obtidos por método indireto na artéria braquial. Essas diferenças são significantes a partir dos 50 anos de idade. Abstract in english INTRODUCTION: Systolic blood pressure (SP) and pulse pressure (PP) rise gradually during the aging process as a consequence of a reduction in arterial elasticity. The measure of systemic arterial pressure (SAP) taken at the root of the aorta has been considered an independent determinant of cardiova [...] scular mortality superior to the values of brachial SAP. AIM: To compare the values of SAP central to those of braquial SAP in patients of different age brackets who have systemic hypertension. METHOD: We evaluated the central SAP at the root of the aorta and the brachial SAP in the left arm using the ocillometric method 244 hypertensive patients who had been submitted to cineangiocoronarography. Five groups of patients were constituted: Group I, 39-49 years-old (y.o.), n = 36; Group II, 50-59 y.o., n = 67; Group III, 60-69 y.o., n = 69; Group IV, 70-79 y.o., n = 46; Group V, > 80 y.o., n = 26. RESULTS: When central SP was compared to brachial SP, it was possible to find significance in patients who were 50 y.o and upwards. It was not possible to find a statistical difference between central diastolic pressure and brachial except in patients between the ages of 60-69 y.o. When comparing central to brachial PP, we observed that central PP was significantly greater (between 11 and 15 mmHg) in all patient above the age of 50 y.o. CONCLUSION: In older people, the values of SP and PP, taken directly at the root of the aorta, are superior to those obtained by indirect means from the brachial artery. These differences are significant from the age of 50 y.o. onwards.

Bruno Bordin, Pelazza; Cesar Augusto Saldanha, Rosa; Sebastião Rodrigues, Ferreira Filho.

2012-09-01

220

Elevated pressure causes endothelial dysfunction in mouse carotid arteries by increasing local angiotensin signaling.  

Science.gov (United States)

Experiments were performed to determine whether or not acute exposure to elevated pressure would disrupt endothelium-dependent dilatation by increasing local angiotensin II (ANG II) signaling. Vasomotor responses of mouse-isolated carotid arteries were analyzed in a pressure myograph at a control transmural pressure (PTM) of 80 mmHg. Acetylcholine-induced dilatation was reduced by endothelial denudation or by inhibition of nitric oxide synthase (N(G)-nitro-l-arginine methyl ester, 100 ?M). Transient exposure to elevated PTM (150 mmHg, 180 min) inhibited dilatation to acetylcholine but did not affect responses to the nitric oxide donor diethylamine NONOate. Elevated PTM also increased endothelial reactive oxygen species, and the pressure-induced endothelial dysfunction was prevented by the direct antioxidant and NADPH oxidase inhibitor apocynin (100 ?M). The increase in endothelial reactive oxygen species in response to elevated PTM was reduced by the ANG II type 1 receptor (AT1R) antagonists losartan (3 ?M) or valsartan (1 ?M). Indeed, elevated PTM caused marked expression of angiotensinogen, the precursor of ANG II. Inhibition of ANG II signaling, by blocking angiotensin-converting enzyme (1 ?M perindoprilat or 10 ?M captopril) or blocking AT1Rs prevented the impaired response to acetylcholine in arteries exposed to 150 mmHg but did not affect dilatation to the muscarinic agonist in arteries maintained at 80 mmHg. After the inhibition of ANG II, elevated pressure no longer impaired endothelial dilatation. In arteries treated with perindoprilat to inhibit endogenous formation of the peptide, exogenous ANG II (0.3 ?M, 180 min) inhibited dilatation to acetylcholine. Therefore, elevated pressure rapidly impairs endothelium-dependent dilatation by causing ANG expression and enabling ANG II-dependent activation of AT1Rs. These processes may contribute to the pathogenesis of hypertension-induced vascular dysfunction and organ injury. PMID:25485905

Zhao, Yingzi; Flavahan, Sheila; Leung, Susan W; Xu, Aimin; Vanhoutte, Paul M; Flavahan, Nicholas A

2015-02-15

221

The arterial load in pulmonary hypertension  

Directory of Open Access Journals (Sweden)

Full Text Available The anatomical differences between the pulmonary and systemic arterial system are the main cause of the difference in distribution of compliance. In the pulmonary arterial system compliance is distributed over the entire arterial system, and stands at the basis of the constancy of the RC-time. This distribution depends on the number of peripheral vessels, which is ?8–10 times more in the pulmonary system than the systemic tree. In the systemic arterial tree the compliance is mainly located in the aorta (80% of total compliance in thoracic-abdominal aorta. The constant RC-time in the pulmonary bed results in proportionality of systolic and diastolic pressure with mean pressure and, in turn, in the constant ratio of oscillatory and mean power.

A. Vonk-Noordegraaf

2010-09-01

222

The compliance of the porcine pulmonary artery depends on pressure and heart rate.  

Science.gov (United States)

1. The influence of mean pulmonary arterial pressure (mean Ppa) on dynamic (Cd) and pseudo-static compliance (Cps) of the pulmonary artery was studied at a constant and a changing heart rate. Cd is the change in cross-sectional area (CSA) relative to the change in Ppa throughout a heart cycle. Cps is the change in mean CSA relative to the change in mean Ppa. If Cd is known, pulmonary blood flow can be computed from the Ppa using a windkessel model. We investigated whether Cps can be interchanged with Cd. 2. In nine anaesthetized pigs, we determined the mean CSA and Cd of the pulmonary artery at various Ppa levels, ranging from approximately 30 to 10 mmHg, established by bleeding. Two series of measurements were carried out, one series at a spontaneously changing heart rate (n = 9) and one series at a constant heart rate (n = 6). To determine CSA a conductance method was used. 3. Cps depended on pressure. The mean CSA versus mean Ppa curves were sigmoid and steepest in the series with the increasing heart rate (established by bleeding). The CSA versus Ppa loop during a heart cycle, giving Cd, was approximately linear and almost closed. The Cd versus mean Ppa relationship was bell shaped. Its width was smaller if the heart rate increased during the series of measurements. The pressure, where Cd was maximum, was higher at higher heart rates. Furthermore, the maximum Cd was not affected by the heart rate. 4. Because the pulmonary artery constricts with increasing heart rate, Cps will be overestimated during procedures where heart rate increases. Cd should be determined on a beat-to-beat basis to calculate flow because it changes with mean pulmonary arterial pressure and heart rate. PMID:9769432

Kornet, L; Jansen, J R; Nijenhuis, F C; Langewouters, G J; Versprille, A

1998-11-01

223

Pressão arterial elevada, excesso de peso e obesidade abdominal em crianças e adolescentes / High blood pressure, overweigth and abdominal obesity in children and adolescents  

Scientific Electronic Library Online (English)

Full Text Available O objetivo deste estudo foi verificar a frequência de pressão arterial elevada em meninos e meninas de 10 a 16 anos de idade, analisando sua associação com o excesso de peso corporal e a obesidade abdominal. Foram avaliadas 764 crianças e adolescentes (365 meninos e 399 meninas) provenientes de cinc [...] o escolas da rede pública de Curitiba. Avaliaram-se a estatura, o peso corporal, a circunferência abdominal e as pressões arteriais sistólica e diastólica de repouso. Foram utilizados o teste t de Student e Qui-Quadrado. Para todas as análises considerou-se p Abstract in english This study was to investigate the frequency of elevated blood pressure in boys and girls aged 10-16 years, and its association with overweight and abdominal obesity. A total of 764 children and adolescents (365 boys and 399 girls) from five public schools of Curitiba City had their height, weight, w [...] aist circumference, resting systolic and diastolic blood pressure measured. Body mass index (kg/m²) was classified in accordance with national reference, for age and gender. Student T-test, Chi-squared Test were calculated. For all analysis, the level of significance was set at p

Deise Cristiane, Moser; Gerusa Eisfeld, Milano; Lilian Messias Sampaio, Brito; Ana Cláudia Kapp, Titski; Neiva, Leite.

2011-12-01

224

The Effects of Cola Acuminata on Arterial Blood Pressure  

OpenAIRE

Caffeine has been proven to be vasoactive and augments the release of calcium from sarcoplasmic reticulum. Interestingly, caffeine is the most active principle of Cola acuminata-commonly consumed in Nigeria. This study is designed to determine its effects on blood pressure using 20 Sprague dawley rats with an average weight of 150g. The animals were subdivided into 2 groups of 10 rats each (control and test groups). The control rats were fed with rat chow while the test groups were fed with s...

Igbinovia, E. N. S.; Ugwu, A. C.; Nwaopara, A. O.; Otamere, H. O.; Adisa, W. A.

2009-01-01

225

Efeitos de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em hipertensas Effects of aquatic exercise on cardiorespiratory fitness and blood pressure in hypertensive women  

Directory of Open Access Journals (Sweden)

Full Text Available O estudo visou avaliar a influência de um programa de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em mulheres hipertensas. Dez hipertensas participaram do programa de exercícios aquáticos - aeróbicos, de fortalecimento, alongamento e relaxamento - duas vezes por semana durante 7 semanas, totalizando 14 sessões. Foram avaliadas pelo teste de esforço cardiorrespiratório antes e após o desenvolvimento do programa. A pressão arterial foi mensurada ao repouso e aos 10, 20 e 30 minutos após o exercício em cada sessão. As variáveis cardiorrespiratórias não apresentaram alterações significativas após o programa, tanto dos valores de limiar de anaerobiose quanto os do pico de esforço. As pressões arteriais sistólica, diastólica e média de repouso permaneceram estáveis no decorrer do programa. Entretanto, no período pós-exercício, os níveis da pressão arterial sistólica (PAS e média (PAM foram significativamente menores, quando comparados aos valores pré-exercício: houve redução média de 6,43 mmHg da PAS e 3,08 mmHg da PAM aos 30 minutos pós-exercício. Assim, o programa de exercícios aquáticos proposto não promove ganho aeróbico efetivo, mas os resultados sugerem que exercícios aquáticos como os propostos, em intensidade próxima ao limiar de anaerobiose, desencadeiam redução dos níveis de pressão arterial no período pós-exercício, em mulheres hipertensas.The aim of this study was to assess the influence of an aquatic exercise program on cardiorespiratory fitness and blood pressure in hypertensive women. Ten hypertensive women took part in the study. The program consisted of aquatic aerobic, strengthening, and stretching exercises in intensity near the anaerobic threshold, besides relaxation, twice a week during 7 weeks, totalling 14 sessions. They were assessed by cardiorespiratory exercise testing before and after program development. Blood pressure was measured at rest before and at 10, 20, and 30 minutes after exercise, at the end of each session. After the hydrotherapy program, cardiorespiratory ranges did not show significant changes, neither at the anaerobic threshold nor at the effort peak. Systolic (SBP, diastolic (DBP, and mean (MBP blood pressure at rest remained stable all through the program. However, SBP and MBP levels at 30-minute rest after exercises, at the end of the program, were significantly lower when compared to pre-exercise ones: there was a mean 6,43 mmHg SBP decrease and a 3,08 mmHg MBP decrease. The hydrotherapy program thus did not promote effective aerobic increase, but results suggest that the proposed exercises, performed at near-anaerobic threshold, may reduce post-exercise SBP and MBP levels in hypertensive women.

Lisiane Piazza

2008-09-01

226

Efeitos de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em hipertensas / Effects of aquatic exercise on cardiorespiratory fitness and blood pressure in hypertensive women  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O estudo visou avaliar a influência de um programa de exercícios aquáticos sobre a aptidão cardiorrespiratória e a pressão arterial em mulheres hipertensas. Dez hipertensas participaram do programa de exercícios aquáticos - aeróbicos, de fortalecimento, alongamento e relaxamento - duas vezes por sem [...] ana durante 7 semanas, totalizando 14 sessões. Foram avaliadas pelo teste de esforço cardiorrespiratório antes e após o desenvolvimento do programa. A pressão arterial foi mensurada ao repouso e aos 10, 20 e 30 minutos após o exercício em cada sessão. As variáveis cardiorrespiratórias não apresentaram alterações significativas após o programa, tanto dos valores de limiar de anaerobiose quanto os do pico de esforço. As pressões arteriais sistólica, diastólica e média de repouso permaneceram estáveis no decorrer do programa. Entretanto, no período pós-exercício, os níveis da pressão arterial sistólica (PAS) e média (PAM) foram significativamente menores, quando comparados aos valores pré-exercício: houve redução média de 6,43 mmHg da PAS e 3,08 mmHg da PAM aos 30 minutos pós-exercício. Assim, o programa de exercícios aquáticos proposto não promove ganho aeróbico efetivo, mas os resultados sugerem que exercícios aquáticos como os propostos, em intensidade próxima ao limiar de anaerobiose, desencadeiam redução dos níveis de pressão arterial no período pós-exercício, em mulheres hipertensas. Abstract in english The aim of this study was to assess the influence of an aquatic exercise program on cardiorespiratory fitness and blood pressure in hypertensive women. Ten hypertensive women took part in the study. The program consisted of aquatic aerobic, strengthening, and stretching exercises in intensity near t [...] he anaerobic threshold, besides relaxation, twice a week during 7 weeks, totalling 14 sessions. They were assessed by cardiorespiratory exercise testing before and after program development. Blood pressure was measured at rest before and at 10, 20, and 30 minutes after exercise, at the end of each session. After the hydrotherapy program, cardiorespiratory ranges did not show significant changes, neither at the anaerobic threshold nor at the effort peak. Systolic (SBP), diastolic (DBP), and mean (MBP) blood pressure at rest remained stable all through the program. However, SBP and MBP levels at 30-minute rest after exercises, at the end of the program, were significantly lower when compared to pre-exercise ones: there was a mean 6,43 mmHg SBP decrease and a 3,08 mmHg MBP decrease. The hydrotherapy program thus did not promote effective aerobic increase, but results suggest that the proposed exercises, performed at near-anaerobic threshold, may reduce post-exercise SBP and MBP levels in hypertensive women.

Lisiane, Piazza; Marice Regina, Menta; Cristiano, Castoldi; José Basileu Caon, Reolão; Rodrigo, Schmidt; Leonardo, Calegari.

2008-09-01

227

Surgical and histopathological effects of topical Ankaferd hemostat on major arterial vessel injury related to elevated intra-arterial blood pressure  

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Full Text Available Objective: The aim of this study was to assess the surgical and histopathological hemostatic effects of topical Ankaferd blood stopper (ABS on major arterial vessel injury related to elevated intra-arterial blood pressure in an experimental rabbit model.Materials and Methods: The study included 14 New Zealand rabbits. ABS was used to treat femoral artery puncture on 1 side in each animal and the other untreated side served as the control. Likewise, for abdominal aortic puncture, only 50% of the aortic injuries received topical liquid ABS and the others did not (control. The experiment was performed under conditions of normal arterial blood pressure and was repeated with a 50% increase in blood pressure. Histopathological analysis was performed in all of the studied animals.Results: Mean bleeding time in the control femoral arteries was 105.0±18.3 s, versus 51.4±9.8 s (p<0.05 in those treated with ABS. Mean blood loss from the punctured control femoral arteries was 5.0±1.5 mg and 1.6±0.4 mg from those treated with ABS (p<0.05. Histopathological examination of the damaged arterial structures showed that ABS induced red blood cell aggregates.Conclusion: ABS administered to experimental major arterial vessel injury reduced both bleeding time and blood loss under conditions of normal and elevated intra-arterial blood pressure. ABS-induced erythroid aggregation was prominent at the vascular tissue level. These findings will inform the design of future experimental and clinical studies on the anti-bleeding and vascular repairing effects of the novel hemostatic agent ABS.

A. Tulga Ulus

2011-09-01

228

Arterial blood oxygen saturation during blood pressure cuff-induced hypoperfusion  

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Pulse oximetry has been one of the most significant technological advances in clinical monitoring in the last two decades. Pulse oximetry is a non-invasive photometric technique that provides information about the arterial blood oxygen saturation (SpO{sub 2}) and heart rate, and has widespread clinical applications. When peripheral perfusion is poor, as in states of hypovolaemia, hypothermia and vasoconstriction, oxygenation readings become unreliable or cease. The problem arises because conventional pulse oximetry sensors must be attached to the most peripheral parts of the body, such as finger, ear or toe, where pulsatile flow is most easily compromised. Pulse oximeters estimate arterial oxygen saturation by shining light at two different wavelengths, red and infrared, through vascular tissue. In this method the ac pulsatile photoplethysmographic (PPG) signal associated with cardiac contraction is assumed to be attributable solely to the arterial blood component. The amplitudes of the red and infrared ac PPG signals are sensitive to changes in arterial oxygen saturation because of differences in the light absorption of oxygenated and deoxygenated haemoglobin at these two wavelengths. From the ratios of these amplitudes, and the corresponding dc photoplethysmographic components, arterial blood oxygen saturation (SpO{sub 2}) is estimated. Hence, the technique of pulse oximetry relies on the presence of adequate peripheral arterial pulsations, which are detected as photoplethysmographic (PPG) signals. The aim of this study was to investigate the effect of pressure cuff-induced hypoperfusion on photoplethysmographic signals and arterial blood oxygen saturation using a custom made finger blood oxygen saturation PPG/SpO{sub 2} sensor and a commercial finger pulse oximeter. Blood oxygen saturation values from the custom oxygen saturation sensor and a commercial finger oxygen saturation sensor were recorded from 14 healthy volunteers at various induced brachial pressures. Both pulse oximeters showed gradual decrease of saturations during induced hypoperfusion which demonstrate the direct relation between blood volumes (PPG amplitudes), arterial vessel stenosis and blood oxygen saturation. The custom made pulse oximeter was found to be more sensitive to SpO{sub 2} changes than the commercial pulse oximeter especially at high occluding pressures.

Kyriacou, P A [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Shafqat, K [School of Engineering and Mathematical Sciences, City University, London EC1V 0HB (United Kingdom); Pal, S K [St Andrew' s Centre for Plastic Surgery and Burns, Broomfield Hospital, Chelmsford, CM1 7ET (United Kingdom)

2007-10-15

229

Invasive intracranial arterial pressure monitoring during endovascular cerebral aneurysms embolization for cerebral perfusion evaluation.  

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The purpose of the study was to define a method of estimation of cerebral blood flow by a determination of parameters of the hemodynamics during neuroendovascular procedures. Materials and Methods. Extracranial and intracranial mean arterial pressure (MAP) was invasively monitored with the help of a transducing system during an endovascular coiling procedure in 19 patients. The measurements were performed at the tip of the guiding catheter and microcatheter placed into internal carotid artery (ICA) C1 segments and of the microcatheter placed into C4 ICA segments, at different stages of the aneurysm repair. Results. As measured, the diameter of the ICA in the C1 and C4 segments did not differ substantially. MAP in the ICA was determined to be 91.2 ± 9.6 mmHg in the skull cavity, and 102.4 ± 6.3 mmHg outside of the skull cavity, with an average difference of 9.2 ± 3.0 mmHg. Conclusion. The difference in MAP, as measured in the ICA outside and inside the skull cavity, was ascribed to the influence of intracranial pressure. Further investigation is required to check the accuracy of invasive intra-arterial pressure recording for an objective and direct measurement of the cerebral perfusion in reference to the intracranial pressure level. PMID:25366620

Netlyukh, Andriy M; Shevaga, Volodymyr M; Yakovenko, Leonid M; Payenok, Angelika V; Salo, Victor M; Kobyletskiy, Oleg Ja

2015-01-01

230

Contributions of tidal lung inflation to human R-R interval and arterial pressure fluctuations  

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We studied the effects of mechanical lung inflation on respiratory frequency R-R interval and arterial pressure fluctuations in nine healthy young adults undergoing elective orthopedic surgery. We conducted this research to define the contribution of pulmonary and thoracic stretch receptor input to respiratory sinus arrhythmia. We compared fast Fourier transform spectral power during three modes of ventilation: (1) spontaneous, frequency-controlled (0.25 Hz) breathing, (2) intermittent positive pressure ventilation (0.25 Hz, with a tidal volume of 8 ml/kg) and (3) high frequency jet ventilation (5.0 Hz, 2.5 kg/cm2), after sedation and vecuronium paralysis. Mean R-R intervals, arterial pressures and arterial blood gas levels were comparable during all three breathing conditions. Respiratory frequency systolic pressure spectral power was comparable during spontaneous breathing and conventional mechanical ventilation, but was significantly reduced during high frequency jet ventilation (P mechanical, than high frequency jet ventilation (P < 0.05). These results suggest that although phasic inputs from pulmonary and thoracic stretch receptors make a statistically significant contribution to respiratory sinus arrhythmia, that contribution is small.

Koh, J.; Brown, T. E.; Beightol, L. A.; Eckberg, D. L.

1998-01-01

231

Current clinical applications of spectral tissue Doppler echocardiography (E/E' ratio as a noninvasive surrogate for left ventricular diastolic pressures in the diagnosis of heart failure with preserved left ventricular systolic function  

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Full Text Available Abstract Congestive heart failure with preserved left ventricular systolic function has emerged as a growing epidemic medical syndrome in developed countries, which is characterized by high morbidity and mortality rates. Rapid and accurate diagnosis of this condition is essential for optimizing the therapeutic management. The diagnosis of congestive heart failure is challenging in patients presenting without obvious left ventricular systolic dysfunction and additional diagnostic information is most commonly required in this setting. Comprehensive Doppler echocardiography is the single most useful diagnostic test recommended by the ESC and ACC/AHA guidelines for assessing left ventricular ejection fraction and cardiac abnormalities in patients with suspected congestive heart failure, and non-invasively determined basal or exercise-induced pulmonary capillary hypertension is likely to become a hallmark of congestive heart failure in symptomatic patients with preserved left ventricular systolic function. The present review will focus on the current clinical applications of spectral tissue Doppler echocardiography used as a reliable noninvasive surrogate for left ventricular diastolic pressures at rest as well as during exercise in the diagnosis of heart failure with preserved left ventricular systolic function. Chronic congestive heart failure, a disease of exercise, and acute heart failure syndromes are characterized by specific pathophysiologic and diagnostic issues, and these two clinical presentations will be discussed separately.

Roux Emmanuel

2007-03-01

232

Systolic and diastolic short-term blood pressure variability and its determinants in patients with controlled and uncontrolled hypertension: A retrospective cohort study.  

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Abstract Absolute blood pressure (BP) values are not the only causes of adverse cardiovascular consequences. BP variability (BPV) has also been demonstrated to be a predictor of mortality for cardiovascular events; however, its determinants are still unknown. This study considers 426 subjects with ambulatory BP monitoring (ABPM) measuring 24-h, diurnal and nocturnal absolute BP values and their standard deviations of the mean, along with nocturnal fall, age, sex and current treatment. Patients were divided in two subgroups, controlled and uncontrolled BP, and BPV of patients with "true" and "false" resistant hypertension was also analyzed. Nocturnal and 24-h BPV were higher in the group with uncontrolled hypertension. Multiple regression analysis showed that absolute BP, age, nocturnal fall, but not sex predicted BPV. Patients with "true" resistant hypertension had greater BPV than "false" resistant hypertension patients. Absolute BP resulted as the main determinant of 24-h and nocturnal BPV but not daytime BPV. Also nocturnal BP fall and age resulted as predictors of BPV in treated and untreated patients. Patients with "true" resistant hypertension have a higher BPV, suggesting a higher sympathetic activation. Evidence is still limited regarding the importance of short-term BPV as a prognostic factor and assessment of BPV cannot yet represent a parameter for routine use in clinical practice. Future prospective trials are necessary to define which targets of BPV can be achieved with antihypertensive drugs and whether treatment-induced reduction in BPV is accompanied by a corresponding reduction in cardiovascular events. PMID:25555153

Pengo, Martino F; Rossitto, Giacomo; Bisogni, Valeria; Piazza, Daniele; Frigo, Anna Chiara; Seccia, Teresa Maria; Maiolino, Giuseppe; Rossi, Gian Paolo; Pessina, Achille C; Calò, Lorenzo A

2015-04-01

233

Frecuencia de la hipertensión arterial y su relación con algunas variables clínicas en pacientes con diabetes mellitus tipo 2 High blood pressure frequency and its relation to some clinical variables in patients diagnosed with type 2 diabetes mellitus  

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Full Text Available Se realizó un estudio descriptivo transversal con 300 pacientes diabéticos tipo 2 ingresados en el Centro de Atención al Diabético de Bayamo, Granma, en el período comprendido entre octubre de 2007 y mayo de 2008, con el objetivo de conocer la frecuencia de hipertensión arterial y su relación con algunas variables clínicas en estos casos. Se revisaron las historias clínicas de cada uno de ellos para obtener datos de los aspectos siguientes: edad, sexo, color de la piel, hábitos tóxicos, edad al comienzo de la diabetes, estado nutricional, circunferencia de la cintura, tensión arterial y complicaciones crónicas de la diabetes. Se encontró hipertensión arterial en 210 pacientes (70 %; de ellos, 57 (27,1 % presentaron hipertensión sistólica aislada, 39 (18,5 % hipertensión diastólica, y 114 (54,4 % hipertensión sistodiastólica. La hipertensión arterial se presentó desde el inicio de la diabetes en el 62,9 %. El 76,1 % de los pacientes hipertensos tenían sobrepeso u obesidad (P=0,0557. Resultó significativa la asociación entre la hipertensión arterial y la cardiopatía isquémica (p= 0,0117. En relación con el ictus y la insuficiencia arterial periférica, aunque la mayoría de los casos eran hipertensos, no llegó a ser estadísticamente significativo (p= 0,8261, p= 0,8600. El 71,1 % de los pacientes con retinopatía diabética y el 75 % con nefropatía diabética eran hipertensos (p= 0,8261, p= 0,8600. Se concluye que la hipertensión arterial tiene una elevada incidencia en los pacientes con diabetes mellitas tipo 2, porque está presente en un porcentaje importante desde el diagnóstico de la diabetes y se asocia significativamente a la presencia de cardiopatía isquémica.A cross-sectional and descriptive study was conducted in 300 patients with type 2 diabetes admitted in Diabetes Care Center of Bayamo, Granma province between October, 2007 and May, 2008 to know the high blood pressure frequency and its relation to some clinical variables in these cases. Medical records of each patient were reviewed to obtain data on the following features: age, sex, skin color, toxic habits, arterial pressure, and chronic complications of diabetes. High blood pressure was present in 210 patients (70 %, from them 57 (27.1 % had isolated systolic hypertension, 39 (18.5 % diastolic hypertension, and 114 (54.4 % systolic-diastolic hypertension. Arterial hypertension was present from onset of diabetes in 62.9 %. The 76.1 % of hypertensive patients had overweight or obesity (p= 0.0557. The relationship was significant between arterial hypertension and ischemic heart disease (p = 0.0117. With regard to ictus and peripheral arterial failure, although most of cases were hypertensive, there was not statistic significance (p= 0.8261, p= 0.8600. The 71,1 % of patients presenting with diabetic retinopathy and the 75 % with diabetic nephropathy were hypertensive (p= 0.8261, p= 0.8600. We conclude that arterial hypertension shows a high incidence in patients with type 2 diabetes mellitus due to its presence in a significant percentage from the diabetes diagnosis and it is markedly associated with presence of ischemic heart disease.

Eduardo Valdés Ramos

2009-12-01

234

Uncontrolled arterial hypertension in primary care – patient characteristics and associated factors  

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PRINCIPLES: Most patients with arterial hypertension are treated in primary care. The objective is to assess characteristics of patients with uncontrolled arterial hypertension and its associated determinants in Swiss primary care. METHOD: Data on 122 adult patients with uncontrolled hypertension (mm Hg >140 systolic and/or >90 diastolic) was collected from the baseline data of the on-going randomised controlled "CoCo" trial: Colour-coded Blood Pressure Control. Patient and general p...

Chmiel, C.; Wang, M.; Senn, O.; Del Prete, V.; Zoller, M.; Rosemann, T.; Steurer-stey, C.

2012-01-01

235

In the trail of a fiber Bragg grating sensor to assess the central arterial pressure wave profile  

Science.gov (United States)

Cardiovascular diseases are one of the primary causes of death in the world. Hemodynamics is the study of the blood propagation and the physics aspects concerned to it, relating pressure, flow and resistance. One of the most important topics on hemodynamics is the evaluation of arterial wave reflections. Recently this physical parameter of the pressure wave propagation through the arterial tree was considered as a novel strong risk factor for cardiovascular diseases. Arterial pressure reflections can be quantified by central pressure profile analysis. In this work we study in the trial of an optical fibre Bragg grating based sensor of assess the central pressure profile, with the goal of to achieve a superior sensitivity, with a better signal quality than electromechanical probes, measured directly in the carotid artery.

Leitão, Cátia; Antunes, Paulo; Bastos, José M.; André, Paulo; Pinto, João. L.

2013-05-01

236

Pulse pressure and pulse pressure index:prediction for and correlation with the severity of coronary artery lesion in patients with coronary artery disease  

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Full Text Available Objective To investigate the correlation between pulse pressure(PP,pulse pressure index(PPI and the severity of coronary artery lesion in patients with CAD,and evaluate the significance of PP and PPI in predicting CAD.Methods The data of 9847 patients who had undergone coronary angiography were collected.The positive coronary angiography(stenosed major vessels ? 50% served as a diagnostic standard of CAD.CAD severity was assessed by Gensini score,and the number of stenosed arteries was counted.Relationship between PP,PPI and the severity of CAD was evaluated by both single factor analysis and multivariate binary logistic regression analysis.Results The CAD patients were found to have higher PP(54.63±15.82 vs 49.74±14.27,P < 0.001 and PPI(0.40±0.07 vs 0.38±0.07,P < 0.001.Furthermore,the severity of CAD were associated with increased PP and PPI.Binary logistic regression analysis showed that PPI was a prominent predictor of the CAD(OR=4.921,95%CI 2.241~10.808,P < 0.001.Conclusion The levels of PP and PPI are significantly correlated with CAD;PPI is the most prominent predictor in diagnosis of CAD.

Lei ZHANG

2011-04-01

237

Estado nutricional y presión arterial de adolescentes escolares / Nutritional status and blood pressure in adolescent students  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: Spanish Abstract in spanish Introducción. La obesidad es el principal factor de riesgo para la hipertensión arterial y se encuentra asociada a una mayor morbilidad, tanto a corto como a largo plazo. Objetivos. Comparar los indicadores antropométricos y de presión arterial en función del estado nutricional, verificar la asociac [...] ión entre el estado nutricional y la presión arterial, y determinar la prevalencia de hipertensión en función del estado nutricional de adolescentes de ambos sexos. Métodos. Estudio descriptivo transversal en 499 escolares adolescentes de 11-15 años. Se valoraron las medidas de peso, estatura, índice de masa corporal (IMC), porcentaje de grasa y presión arterial. Se utilizó el IMC para clasificar en categorías (normopeso, sobrepeso y obesos) y la prevalencia de hipertensión se determinó a través de valores superiores del percentilo 95. Resultados. De acuerdo con la clasificación según el IMC, el 81% de las mujeres y el 76,5% de los varones mostraron normopeso. El 15,7% de las mujeres y el 15,5% de los varones evidenciaron sobrepeso; y el 8% de los varones y el 3,3% de las mujeres presentaron obesidad. Según la clasificación de la presión arterial, se observó hipertensión en los varones (6,4%) y en las mujeres (9%). Hubo asociación entre el estado nutricional y la presión arterial (varones: ?²= 53,48; y mujeres: ?² = 85,21). Conclusión. Se determinó que los adolescentes con sobrepeso y obesidad presentaron mayor adiposidad corporal y presión arterial que sus similares normopesos. A su vez, se verificó una asociación entre el estado nutricional y la presión arterial en ambos sexos. La prevalencia de hipertensión fue mayor a medida que aumentaba el IMC. Abstract in english Introduction. Obesity is the main risk factor for arterial hypertension andis associatedwitha higher morbidity, both in the short and long term. Objectives. To compare anthropometric and blood pressure indicators in terms of the nutritional status, to verify the relationship between nutritional stat [...] us and blood pressure, and to establish the prevalence of hypertension in terms of the nutritional status in both male and female adolescents. Methods. Cross-sectional, descriptive study on 499 adolescent students aged 11-15 years old. Weight, height, body mass index (BMI), fat percentage, and blood pressure were measured and assessed. The BMI was used to classify participants (normal weight, overweight, obese), and the prevalence of hypertension was determined using values above the 95th percentile. Results. As per the BMI classification, 81% of girls and 76.5% ofboys had normal weight, 15.7% of girls and 15.5% of boys were overweight, and 3.3% of girls and 8% of boys were obese. As per the blood pressure classification, hypertension was observed in 6.4% of boys and in 9% of girls. A relationship was found between nutritional status and blood pressure (boys: c2= 53.48; girls: c2= 85.21). Conclusion. Overweight and obese adolescents had more body fat and a higher blood pressure than normal weight adolescents. Also, a relationship was determined betweennutritional status and blood pressure in both male and female students. The higher the BMI, the higher the prevalence of hypertension.

Marco, Cossio-Bolaños; Wilbert, Cossio-Bolaños; Adriana Araya, Menacho; Rossana, Gómez Campos; Yuri Muniz da, Silva; Carlos Pablos, Abella; Miguel, de Arruda.

2014-08-01

238

Intensidades de treinamento resistido e pressão arterial de idosas hipertensas - um estudo piloto / Resistance training intensities and blood pressure of hypertensive older women - a pilot study  

Scientific Electronic Library Online (English)

Full Text Available INTRODUÇÃO: Observa-se que a literatura apresenta uma lacuna acerca da intensidade ideal de treinamento resistido para idosos hipertensos, os poucos estudos existentes utilizam treinamentos com diferentes intensidades. OBJETIVO: Verificar o efeito de duas intensidades de treinamento resistido sobre [...] a pressão arterial de idosas hipertensas controladas. Métodos: Dezesseis idosas hipertensas, controladas por medicação anti-hipertensiva, foram divididas em dois grupos através de sorteio. Nove pacientes foram submetidas a treinamento resistido moderado (G1) e sete, a treinamento resistido leve (G2). As pacientes realizaram oito semanas de treinamento resistido, com frequência de três vezes por semana em dias alternados, no período vespertino. Os exercícios realizados foram respectivamente: leg press, supino reto, extensão de joelhos, puxada frontal, flexão de joelhos, abdução de ombro, abdução unilateral de quadril com cross over e rosca direta com barra. RESULTADOS: As pacientes do G1 apresentaram redução tanto nos valores de repouso da pressão arterial diastólica (PAD) p Abstract in english BACKGROUND: The optimum intensity of resistance training for hypertensive elderly has not been studied yet and the few studies in the literature used training with distinct intensities. Objective: To verify the effect of two resistance training intensities on blood pressure (BP) of elderly women wit [...] h controlled hypertension. METHODS: Sixteen older women with hypertension controlled by anti-hypertensive drug were randomly divided into two groups. Nine patients were submitted to moderate resistance training (G1) and seven patients were submitted to mild resistance training (G2). The patients underwent eight weeks of resistance training, with frequency of three times per week on alternate days in the afternoon. The exercises performed were: leg press, bench press, knee extension, lat pull-down, knee flexion, shoulder abduction, standing cable hip abduction and biceps curl. RESULTS: G1 patients presented reduction in both resting values in diastolic blood pressure (DBP) p

Eline Silva da, Cunha; Patrícia Angélica de, Miranda; Silva, Nogueira; Eduardo Caldas, Costa; Eliane Pereira da, Silva; Gardênia Maria Holanda, Ferreira.

2012-12-01

239

Intraarterial Pressure Gradients After Randomized Angioplasty or Stenting of Iliac Artery Lesions  

International Nuclear Information System (INIS)

Purpose: To determine initial technical results of percutaneous transluminal angioplasty (PTA) and stent procedures in the iliac artery, mean intraarterial pressure gradients were recorded before and after each procedure. Methods: We randomly assigned 213 patients with typical intermittent claudication to primary stent placement (n= 107) or primary PTA (n= 106), with subsequent stenting in the case of a residual mean pressure gradient of > 10 mmHg (n= 45). Eligibility criteria included angiographic iliac artery stenosis (> 50% diameter reduction) and/or a peak systolic velocity ratio > 2.5 on duplex examination. Mean intraarterial pressures were simultaneously recorded above and below the lesion, at rest and also during vasodilatation in the case of a resting gradient ? 10 mmHg. Results: Pressure gradients in the primary stent group were 14.9 ± 10.4 mmHg before and 2.9 ± 3.5 mmHg after stenting. Pressure gradients in the primary PTA group were 17.3 ± 11.3 mmHg pre-PTA, 4.2 ± 5.4 mmHg post-PTA, and 2.5 ± 2.8 mmHg after selective stenting. Compared with primary stent placement, PTA plus selective stent placement avoided application of a stent in 63% (86/137) of cases, resulting in a considerable cost saving. Conclusion: Technical results of primary stenting and PTA plus selective stenting are similar in terms of residual pressure gradients

240

Medida da pressão arterial em crianças e adolescentes: recomendações das diretrizes de hipertensão arterial e prática médica atual Blood pressure measurement in children and adolescents: guidelines of high blood pressure recommendations and current clinical practice  

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Full Text Available OBJETIVO: Identificar, em crianças e adolescentes (7 a 17 anos, rede pública e privada de ensino, a freqüência de indivíduos já submetidos à medida da pressão arterial (MPA, o número de vezes, os locais em que foi realizada a aferição e o resultado informado. MÉTODOS: Estudo transversal. Amostragem por conglomerados em 40 escolas, nível fundamental e médio, sorteadas. Cálculo da amostra baseado na prevalência esperada de HAS em crianças e adolescentes. Protocolo: questionário sobre realização prévia de MPA (em caso afirmativo, quantas vezes, quando foi a última medida, o local e o resultado da medida e duas MPA. Variáveis independentes: sexo, faixa etária, classe econômica, escola pública ou privada. RESULTADOS: Amostra constituída de 1253 estudantes 1215 responderam ao questionário (97% 531 do sexo masculino média de 12,4 ± 3 anos. Prevalência de HAS: 7,7% 348 estudantes (29% já haviam medido a PA (54% 1 vez 35% 2 a 4 vezes 11% 5 ou mais 53% há menos de 1 ano. Posto de Saúde, residência, hospital e consultório foram os locais mais mencionados (27%, 16%, 15% e 14%, respectivamente. Houve associação significante entre prévia MPA com faixa etária de 15 a 17 anos, classes econômicas A e B e ser estudante de escola privada. CONCLUSÃO: Apesar das recomendações, há baixa freqüência de MPA (29% em crianças e adolescentes, demonstrando que a mesma não foi ainda incorporada na prática clínica.OBJECTIVE: To determine, in a school-based sample of children and adolescents, aged from 7 to 17 years, of both gender, in public and private schools, the frequency of students already submitted to blood pressure measure. METHODS: A cross-sectional study was carried out, sampling from a population pool of elementary and middle schools, randomly selected. The sample was calculated based on the expected prevalence of hypertension for the age group. Data were collected through a questionnaire. Blood pressure was measured twice and hypertension was defined as mean systolic and/or diastolic blood pressure over the 95th percentile. Independent variables studied: sex; age groups; economic status; public/private school. RESULTS: The final sample included 1253 students. The response rate was 97%: 1215 students; 531 males; mean age 12,4±3 years (236 from 7 to 9 years; 638 from 10 to 14 years; 341 from 15 to 17 years. Prevalence of hypertension was 7.7%; 348 students (29% were already submitted to blood pressure measures (54% once; 35% 2 to 4 times; 11% 5 or more times. High economic status, private school and adolescent group were significantly associated to previous blood pressure measure. CONCLUSION: Despite of pediatric consensus statements and guidelines recommendations about importance of blood pressure measure at every examination after age 3 years, there is a very low frequency of this practice (29% in children and adolescents.

Maria Alayde Mendonça da Silva

2007-04-01

241

Influence of anxiety on blood pressure and heart rate during dental treatment / Influência da ansiedade na pressão arterial e frequência cardíaca durante o tratamento odontológico  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese OBJETIVO: Avaliar a influência da ansiedade detectadas por meio de uma escala de ansiedade sobre os níveis de pressão arterial e a frequência cardíaca, durante o atendimento odontológico de pacientes das Clínicas de Odontologia do Centro Universitário de São José do Rio Preto, São Paulo, Brasil. MET [...] ODOLOGIA: Foram selecionados ao acaso 60 voluntários que receberam atendimento odontológico de urgência. Foi utilizada uma escala para avaliar o grau de ansiedade dos voluntários. Foi verificada também a pressão arterial e a frequência cardíaca dos pacientes em três períodos distintos: pré, trans e pós-anestesia odontológica. RESULTADOS: A ansiedade não foi afetada pelas faixas etárias, apenas pelo gênero. A ansiedade não deve ser uma barreira, entre profissional/paciente e, ainda, a ansiedade apresentada não é um sinal clínico levado em consideração para a aplicação de medidas de controle. CONCLUSÃO: Não houve alteração da pressão arterial sistólica, diastólica e da frequência cardíaca em relação ao grau de ansiedade e dor e ao tipo de solução anestésica empregada. Abstract in english PURPOSE: To evaluate the influence of anxiety on blood pressure and heart rate during dental care in patients of the Dentistry Clinic in Rio Preto University Center - UNIRP, São José do Rio Preto, São Paulo, Brazil. METHODS: A sample of 60 volunteers who sought for the dental screening service was s [...] elected. We used a scale to evaluate the volunteers' anxiety level. Blood pressure and heart rate of patients were also checked in different periods of the dental treatment. RESULTS: Most of the volunteers were women. The relation between anxiety and pain before treatment, revealed that 54 (90.0%) had no pain. The patients had low anxiety towards the use of different anesthetic solutions used during dental procedures. There was no statistically significant difference concerning to systolic blood pressure at first and, after application of anesthetic, given the degree of anxiety. Heart rate does not change as a function of anxiety. There is a slight change in heart rate after anesthesia, and it soon gets back to normal. CONCLUSION: There was no difference in behavior of systolic and diastolic blood pressure in relation to the anxiety level and pain, measured before, during and after the procedure. Heart rate did not change during dental treatment in the patient anxiety level.

Jean Carlos Fernandes, Goulart; Matheus Dias, Pinheiro; Rodrigo Ventura, Rodrigues; Fabiano de Sant' Ana dos, Santos; Alex Tadeu, Martins; Fábio Luiz Ferreira, Scannavino.

242

Association between metabolic syndrome and parameters of 24-hour blood pressure ambulatory monitoring / Associação entre síndrome metabólica e parâmetros da monitorização ambulatorial da pressão arterial de 24 horas  

Scientific Electronic Library Online (English)

Full Text Available OBJETIVO: Investigar associação entre síndrome metabólica (SM) e parâmetros da monitorização da pressão arterial de 24 horas (MAPA) como medida de risco cardiovascular (RCV). SUJEITOS E MÉTODOS: Foram estudados 136 pacientes hipertensos, ambos sexos, idade entre 29 e 83 anos. RCV foi definido pela p [...] resença de, no mínimo, três das seguintes condições: 1) pressão arterial sistólica/diastólica ? 140/90 mmHg, ausência/atenuação do descenso noturno e pressão de pulso (PP) ? 53 mmHg, 2) pressão de pulso 24h (PP24h), 3) sono (PPS), 4) vigília (PPV) e 5) descenso noturno. RESULTADOS: PPV, PPS e PP24h estiveram aumentadas em 54% dos pacientes. Hipertrigliceridemia (52%), HDL baixo (72,8%), obesidade abdominal (60,3%), SM (58,1%), dislipidemia (88,8%), sobrepeso (74,3%) e obesidade (33,8%) estavam elevados. SM, ajustada pela idade, foi associada a elevado RCV (OR = 4,5 e OR = 3,6), a PP24h (OR = 2,3 e OR = 4,7) e a PPS (OR = 2,2 e OR = 4,6). CONCLUSÕES: SM foi altamente prevalente e correlacionada aos parâmetros da pressão arterial de 24 horas alterados. Abstract in english OBJECTIVE: To investigate associations between metabolic syndrome (MS) and 24-hour blood pressure parameters as a measure of cardiovascular risk (CVR). SUBJECTS AND METHODS: 136 hypertensive subjects, of both sexes, aged between 29 and 83 years were studied. CVR was defined as having at least three [...] of the following conditions: 1) systolic/diastolic blood pressure (BP) ? 140/90 mmHg, absence/atennuation of nighttime fall in BP during sleep, pulse pressure (PP) ? 53 mmHg; 2) 24-h PP > 53 mmHg, 3) nighttime PP > 53 mmHg, 4) daytime PP > 53 mmHg and 5) nighttime fall in BP during sleep. RESULTS: The 24-h PP, daytime PP and nighttime PP were elevated in 54% of the population. Hypertriglyceridemia (52%), low HDL (72.8%), abdominal obesity (60.3%), MS (58.1%), dyslipidemia (88.8%), overweight (74.3%) and obesity (33.8%) were also elevated. Age-adjusted MS was associated with higher CVR (OR = 4.5 and 3.6), 24-h PP (OR = 2.3 and 4.7), and daytime PP (OR = 2.2 and 4.6). CONCLUSIONS: MS was highly prevalent and correlated with altered 24-hour blood pressure parameters.

Mariana Santos, Felisbino-Mendes; Tatiane, Géa-Horta; Antônio Luiz Pinho, Ribeiro; Gilberto, Kac; Salete Maria de Fátima, Silqueira; Gustavo, Velásquez-Meléndez.

2011-08-01

243

Leave-one-out prediction error of systolic arterial pressure time series under paced breathing  

CERN Document Server

In this paper we show that different physiological states and pathological conditions may be characterized in terms of predictability of time series signals from the underlying biological system. In particular we consider systolic arterial pressure time series from healthy subjects and Chronic Heart Failure patients, undergoing paced respiration. We model time series by the regularized least squares approach and quantify predictability by the leave-one-out error. We find that the entrainment mechanism connected to paced breath, that renders the arterial blood pressure signal more regular, thus more predictable, is less effective in patients, and this effect correlates with the seriousness of the heart failure. The leave-one-out error separates controls from patients and, when all orders of nonlinearity are taken into account, alive patients from patients for which cardiac death occurred.

Ancona, N; Marinazzo, D; Nitti, L; Pellicoro, M; Pinna, G D; Stramaglia, S

2004-01-01

244

Accuracy of invasive arterial pressure monitoring in cardiovascular patients: an observational study.  

Science.gov (United States)

IntroductionCritically ill patients and patients undergoing high-risk and major surgery, are instrumented with intra-arterial catheters and invasive blood pressure is considered the ¿gold standard¿ for arterial pressure monitoring. Nonetheless, artifacts due to inappropriate dynamic response of the fluid-filled monitoring systems may lead to clinically relevant differences between actual and displayed pressure values. We sought to analyze the incidence and causes of resonance/underdamping phenomena in patients undergoing major vascular and cardiac surgery.MethodsArterial pressures were measured invasively and, according to the fast-flush Gardner¿s test, each patient was attributed to one of two groups depending on the presence (R-group) or absence (NR-group) of resonance/underdamping. Invasive pressure values were then compared with the non-invasive ones.ResultsA total of 11,610 pulses and 1,200 non-invasive blood pressure measurements were analyzed in 300 patients. Ninety-two out of 300 (30.7%) underdamping/resonance arterial signals were found. In these cases (R-group) systolic invasive blood pressure (IBP) average overestimation of non-invasive blood pressure (NIBP) was 28.5 (15.9) mmHg (P diameter (20 vs. 18 gauge) (P <0.0001; OR¿=¿0.34) and sedation (P =0.0131; OR¿=¿0.5). The ROC curve for the maximal pressure¿time ratio, showed an optimum selected cut-off point of 1.67 mmHg/msec with a specificity of 97% (95% CI: 95.13 to 99.47%) and a sensitivity of 77% (95% CI: 67.25 to 85.28%) and an area under the ROC curve by extended trapezoidal rule of 0.88.ConclusionPhysicians should be aware of the possibility that IBP can be inaccurate in a consistent number of patients due to underdamping/resonance phenomena. NIBP measurement may help to confirm/exclude the presence of this artifact avoiding inappropriate treatments. PMID:25433536

Romagnoli, Stefano; Ricci, Zaccaria; Quattrone, Diego; Tofani, Lorenzo; Tujjar, Omar; Villa, Gianluca; Romano, Salvatore M; De Gaudio, A

2014-11-30

245

Percutaneous renal artery stenting reduces arterial blood pressure, but what about renal function? A single-center experience  

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Full Text Available Objective: To assess the effects of percutaneous transluminal angioplasty and stenting (PTRA/S on arterial blood pressure and renal function.Methods: A retrospective chart review of patients undergoing PTRA/S at our institution between December 2003 and September 2006 was done. Follow-up data were derived from hospital records. Estimated glomerular filtration rate (EGFR was used as the marker of renal function. To evaluate the pre- and post-procedure values in individual patients the paired t test and Wilcoxon signed-rank tests were used.Results: Thirty-six patients (16 women, 30 men; mean age 59±15 years, range: 25-83 years underwent 43 PTRA/S interventions at our institution. The mean duration of follow-up was 9.3±8.6 (range 2-28 months. We observed no significant change in EGFR from pre-procedure to that obtained at follow-up (71.4±40.2 mL/min vs.73.3±39.0 mL/min; p=0.483. Mean arterial blood pressure (MABP, however, was reduced significantly: pre-procedure MABP-123±22 mmHg; post-procedure follow-up value of 101±14 mmHg (p <0.001. The mean number of antihypertensive medications used at the time of intervention was 2.1±1.0 (range: 0-4, whereas at follow-up, this number had decreased to 1.3±1.0 (range: 0-4; p<0.001. In patients with renal impairment (EGFR ?59 mL/min, 41% showed improvement, 29% showed no change and 29% demonstrated deterioration in EGFR. Conclusion: PTRA/S may preserve renal function, especially in patients with pre-procedural impaired renal function.

Erkan Dervi?o?lu

2010-02-01

246

A simple model of cerebral blood flow dependence on arterial blood pressure  

OpenAIRE

It is shown that the dependence of the cerebral blood flow (CBF) on mean arterial blood pressure (MABP) can be described with a simple model having the following assumptions. Below certain MABP (denoted as MABP1) there are no autoregulatory or feedback mechanisms influencing CBF. Between MABP1 and MABP2 (MABP at which breakthrough accurs) there is a linear (on MABP) dependent feedback with a sloap depending very much on the individual considered. The classical autoregulation...

Gersten, Alexander

2011-01-01

247

Synchronization between arterial blood pressure and cerebral oxyhaemoglobin concentration investigated by wavelet cross-correlation.  

OpenAIRE

Wavelet cross-correlation (WCC) is used to analyse the relationship between low-frequency oscillations in near-infrared spectroscopy (NIRS) measured cerebral oxyhaemoglobin (O(2)Hb) and mean arterial blood pressure (MAP) in patients suffering from autonomic failure and age-matched controls. Statistically significant differences are found in the wavelet scale of maximum cross-correlation upon posture change in patients, but not in controls. We propose that WCC analysis of the relationship betw...

Rowley, Ab; Payne, Sj; Tachtsidis, I.; Ebden, Mj; Whiteley, Jp; Gavaghan, Dj; Tarassenko, L.; Smith, M.; Elwell, CE; Delpy, Dt

2007-01-01

248

Mechanisms of Inhaled Fine Particulate Air Pollution–induced Arterial Blood Pressure Changes  

OpenAIRE

Background: Epidemiologic studies suggest a positive association between fine particulate matter and arterial blood pressure, but the results have been inconsistent. Objectives: We investigated the effect of ambient particles on systemic hemodynamics during a 5-hr exposure to concentrated ambient air particles (CAPs) or filtered air (FA) in conscious canines. Methods: Thirteen dogs were repeatedly exposed via permanent tracheostomy to CAPs (358.1 ± 306.7 ?g/m\\(^3\\), mean ± SD) or FA in a c...

Bartoli, Carlo R.; Wellenius, Gregory A.; Akiyama, Ichiro; Lee, Lani M.; Okabe, Kazunori; Diaz, Edgar; Lawrence, Joy E.; Coull, Brent Andrew; Verrier, Richard Leonard; Godleski, John Joseph

2008-01-01

249

Dietary sodium and arterial pressure: problems of studies within a single population.  

OpenAIRE

The nature of the relationship between dietary sodium and arterial pressure remains uncertain, largely because of the difficulty of investigating this relationship within a single population. There are two main hypotheses: one requires that hypertensive and normotensive patients differ in their sodium intake, the other that they differ in their susceptibility to dietary sodium. Neither hypothesis has been fully explored. In this paper the types of study required to test each hypothesis are co...

Watt, G. C.; Foy, C. J.

1982-01-01

250

Effects of ?-adrenergic receptor agonists on drinking and arterial blood pressure in young and old rats  

OpenAIRE

These experiments examined water-drinking and arterial blood pressure responses to ?-adrenergic receptor activation in young (4 mo), “middle-aged” adult (12 mo), and old (29 mo) male rats of the Brown-Norway strain. We used isoproterenol to simultaneously activate ?1- and ?2-adrenergic receptors, salbutamol to selectively activate ?2-adrenergic receptors, and the combination of isoproterenol and the ?2-adrenergic receptor antagonist ICI 118,551 to stimulate only ?1-adrenergic recept...

Thunhorst, Robert L.; Grobe, Connie L.; Beltz, Terry G.; Johnson, Alan Kim

2011-01-01

251

Fourier Analysis of Peripheral Blood Pressure and Flow in Intraoperative Assessment of Infrainguinal Arterial Reconstructions  

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Full Text Available AIM: To assess infrainguinal arterial reconstructions by intraoperative flowmetry under the distal anastomosis using a fast Fourier transformation; calculate and compare the amplitude ratios of peripheral arterial blood pressure and volume flow before and after drug-induced vasodilation of occluded bypass grafts and bypass grafts that have been patent at least for 1 year. To find what magnitude of the change of these ratios indicate a long-term patency of the bypass grafting. PATIENTS AND METHODS: We compared the results of the intraoperative flowmetry tests of 97 patients with infrainguinal arterial reconstructions. The patients were divided into two groups based on the graft status: the grafts in 49 patients were patent for at least a year, and 48 patients had failed bypass. We used a fast Fourier transform (FFT of the pressure and blood flow waves and compared the ratios of their amplitudes before and after administration of a vasodilator drug into the graft. Comparing the ratios obtained before and those after administration of the drug we quantified their change in each group and analysed them. RESULTS: After a drug-induced vasodilation, the blood pressure and flow amplitude ratios for the group with compromised reconstructions were less than 1.9 times smaller than those before drug infusion, while for the group with bypass grafts that had been functional for at least 12 months the ratios declined by more than 1.9?2 times. CONCLUSION: The magnitude of the change of amplitude ratios of the peripheral pressure and volume flow after drug-induced vasodilation can be used to make an assessment of the bypass graft and the distal arterial segment.

Cheshmedzhiev Mihail V.

2014-08-01

252

Pressure profile and morphology of the arteries along the giraffe limb.  

Science.gov (United States)

Giraffes are the tallest animals on earth and the effects of gravity on their cardiovascular system have puzzled physiologists for centuries. The authors measured arterial and venous pressure in the foreleg of anesthetized giraffes, suspended in upright standing position, and determined the ratio between tunica media and lumen areas along the length of the femoral/tibial arteries in the hindleg. Volume fraction of elastin, density of vasa vasorum and innervations was estimated by stereology. Immunohistological staining with S100 was used to examine the innervation. The pressure increase in the artery and vein along the foreleg was not significantly different from what was expected on basis of gravity. The area of the arterial lumen in the hindleg decreased towards the hoof from 11.2 ± 4.2 to 0.6 ± 0.5 mm(2) (n = 10, P = 0.001), but most of this narrowing occurred within 2-4 cm immediately below the knee. This abrupt narrowing was associated with a marked increase in media to lumen area ratio (from 1.2 ± 0.5 to 7.8 ± 2.5; P = 0.001), and a decrease in mean volume fraction of elastin from 38 ± 6% proximal to the narrowing to 5.8 ± 1.1% distally (P = 0.001). The narrowing had a six-fold higher innervation density than the immediate distal and proximal regions. The sudden narrowing was also observed in the hind legs of neonates, indicating that it does not develop as an adaptation to the high transmural pressure in the standing giraffe. More likely it represents a preadaptation to the high pressures experienced by adult giraffes. PMID:21207038

Østergaard, Kristine Hovkjaer; Bertelsen, Mads F; Brøndum, Emil T; Aalkjaer, Christian; Hasenkam, J Michael; Smerup, Morten; Wang, Tobias; Nyengaard, Jens Randel; Baandrup, Ulrik

2011-07-01

253

Pressure profile and morphology of the arteries along the giraffe limb  

DEFF Research Database (Denmark)

Giraffes are the tallest animals on earth and the effects of gravity on their cardiovascular system have puzzled physiologists for centuries. The authors measured arterial and venous pressure in the foreleg of anesthetized giraffes, suspended in upright standing position, and determined the ratio between tunica media and lumen areas along the length of the femoral/tibial arteries in the hindleg. Volume fraction of elastin, density of vasa vasorum and innervations was estimated by stereology. Immunohistological staining with S100 was used to examine the innervation. The pressure increase in the artery and vein along the foreleg was not significantly different from what was expected on basis of gravity. The area of the arterial lumen in the hindleg decreased towards the hoof from 11.2 ± 4.2 to 0.6 ± 0.5 mm(2) (n = 10, P = 0.001), but most of this narrowing occurred within 2-4 cm immediately below the knee. This abrupt narrowing was associated with a marked increase in media to lumen area ratio (from 1.2 ± 0.5 to 7.8 ± 2.5; P = 0.001), and a decrease in mean volume fraction of elastin from 38 ± 6% proximal to the narrowing to 5.8 ± 1.1% distally (P = 0.001). The narrowing had a six-fold higher innervation density than the immediate distal and proximal regions. The sudden narrowing was also observed in the hind legs of neonates, indicating that it does not develop as an adaptation to the high transmural pressure in the standing giraffe. More likely it represents a preadaptation to the high pressures experienced by adult giraffes.

Østergaard, Kristine Hovkjær; Bertelsen, Mads Frost

2011-01-01

254

Fiabilidade da medição da Tensão Arterial: revisão teórica La fiabilidad de la medida de presión arterial: revisión teórica Validity of arterial blood pressure measurement: theoretical review  

Directory of Open Access Journals (Sweden)

Full Text Available A hipertensão arterial é um dos problemas de saúde pública mais importantes, sobretudo nos países desenvolvidos. É razoavelmente comum, facilmente diagnosticada e tem prognóstico reservado quando não tratada. Efectuou-se a pesquisa através das bases de dados EBSCO (Academic Search Premier, Sport diskus e a Medline, utilizando as palavras/ expressões- chave: “validation, accuracy, blood pressure measurement, reproducibility, sphygmomanometer, mercury, oscillometer e dinamap”. Os critérios de selecção basearam-se na pertinência, metodologia e data mais recente de elaboração. O instrumento considerado gold standart é o Esfigmomanómetro (EM; contudo, o mercúrio é tóxico para o ambiente, pelo que surgiu a necessidade da sua substituição por instrumentos com outra tecnologia. Além disso, acredita-se que 50% dos EM não estão em condições de serem utilizados. Braçadeiras menores que o desejável sobrestimam a Tensão Arterial (TA. Acredita-se também que 23% dos profissionais de saúde nunca tenham calibrado os seus instrumentos e que 40% não se recorde da data em que o fez; em 2/3 tal procedimento tinha ocorrido há mais de um ano, apesar de ser simples e pouco dispendioso. Recomenda-se uma calibração anual.La hipertensión es uno de los problemas de salud pública más importantes, sobre todo en los países desarrollados. Es bastante común, fácil de diagnosticar y tiene pronóstico reservado si no es tratada. Se llevó a cabo una investigación a través de las bases de datos EBSCO (Academic Search Premier, Sport diskus e a Medline, utilizando las palabras/expresiones clave: “validation, accuracy, blood pressure measurement, reproducibility, sphygmomanometer, mercury, oscillometer e dinamap”. Los criterios de selección se basaron en la pertinencia, la metodología y la fecha más reciente de elaboración. El instrumento considerado gold standart es el esfigmómetro (EM; sin embargo, el mercurio es tóxico para el medio ambiente, de ahí que surgiera la necesidad de su sustitución por instrumentos con otra tecnología. Además, se cree que el 50% de EM no está en condiciones de ser utilizado. Las abrazaderas menores de lo deseable sobrestiman la tensión arterial (TA. También se cree que el 23% de los profesionales de la salud nunca ha calibrado sus instrumentos y que el 40% no se acuerda de la fecha en la que lo ha hecho; 2/3 habían hecho esta prueba hace más de un año a pesar de ser simple y poco dispendiosa. Se recomienda una calibración anual.Arterial hypertension is one of the most important public health problems, especially in developed countries. It is reasonably common, easy to diagnose and has a limited prognosis when not treated. The research was done using the keywords: validation, accuracy, blood pressure measurement, reproducibility, sphygmomanometer, mercury, oscillometer e dinamap” in “Academic Search Premier, Sport diskus and Medline”; selecting the articles by methodology, relevance and publication date. The “gold standard” instrument is the sphygmomanometer; however, mercury is toxic, and so it must be substituted by other technology. In addition, 50% of sphygmomanometers are not in good condition for clinical use. Cuffs smaller than necessary over-estimate arterial blood pressure. It seems that 23% of health professionals have never calibrated the sphygmomanometer and 40% of the others did not remember when they did this; in 2/3 this situation has continued for longer than one year, despite being cheap and simple. Annual calibration is recommended.

Mónica Santos

2010-07-01

255

Fiabilidade da medição da Tensão Arterial: revisão teórica / Validity of arterial blood pressure measurement: theoretical review / La fiabilidad de la medida de presión arterial: revisión teórica  

Scientific Electronic Library Online (English)

Full Text Available SciELO Portugal | Language: Portuguese Abstract in portuguese A hipertensão arterial é um dos problemas de saúde pública mais importantes, sobretudo nos países desenvolvidos. É razoavelmente comum, facilmente diagnosticada e tem prognóstico reservado quando não tratada. Efectuou-se a pesquisa através das bases de dados EBSCO (Academic Search Premier, Sport dis [...] kus e a Medline), utilizando as palavras/ expressões- chave: “validation, accuracy, blood pressure measurement, reproducibility, sphygmomanometer, mercury, oscillometer e dinamap”. Os critérios de selecção basearam-se na pertinência, metodologia e data mais recente de elaboração. O instrumento considerado gold standart é o Esfigmomanómetro (EM); contudo, o mercúrio é tóxico para o ambiente, pelo que surgiu a necessidade da sua substituição por instrumentos com outra tecnologia. Além disso, acredita-se que 50% dos EM não estão em condições de serem utilizados. Braçadeiras menores que o desejável sobrestimam a Tensão Arterial (TA). Acredita-se também que 23% dos profissionais de saúde nunca tenham calibrado os seus instrumentos e que 40% não se recorde da data em que o fez; em 2/3 tal procedimento tinha ocorrido há mais de um ano, apesar de ser simples e pouco dispendioso. Recomenda-se uma calibração anual. Abstract in spanish La hipertensión es uno de los problemas de salud pública más importantes, sobre todo en los países desarrollados. Es bastante común, fácil de diagnosticar y tiene pronóstico reservado si no es tratada. Se llevó a cabo una investigación a través de las bases de datos EBSCO (Academic Search Premier, S [...] port diskus e a Medline), utilizando las palabras/expresiones clave: “validation, accuracy, blood pressure measurement, reproducibility, sphygmomanometer, mercury, oscillometer e dinamap”. Los criterios de selección se basaron en la pertinencia, la metodología y la fecha más reciente de elaboración. El instrumento considerado gold standart es el esfigmómetro (EM); sin embargo, el mercurio es tóxico para el medio ambiente, de ahí que surgiera la necesidad de su sustitución por instrumentos con otra tecnología. Además, se cree que el 50% de EM no está en condiciones de ser utilizado. Las abrazaderas menores de lo deseable sobrestiman la tensión arterial (TA). También se cree que el 23% de los profesionales de la salud nunca ha calibrado sus instrumentos y que el 40% no se acuerda de la fecha en la que lo ha hecho; 2/3 habían hecho esta prueba hace más de un año a pesar de ser simple y poco dispendiosa. Se recomienda una calibración anual. Abstract in english Arterial hypertension is one of the most important public health problems, especially in developed countries. It is reasonably common, easy to diagnose and has a limited prognosis when not treated. The research was done using the keywords: validation, accuracy, blood pressure measurement, reproducib [...] ility, sphygmomanometer, mercury, oscillometer e dinamap” in “Academic Search Premier, Sport diskus and Medline”; selecting the articles by methodology, relevance and publication date. The “gold standard” instrument is the sphygmomanometer; however, mercury is toxic, and so it must be substituted by other technology. In addition, 50% of sphygmomanometers are not in good condition for clinical use. Cuffs smaller than necessary over-estimate arterial blood pressure. It seems that 23% of health professionals have never calibrated the sphygmomanometer and 40% of the others did not remember when they did this; in 2/3 this situation has continued for longer than one year, despite being cheap and simple. Annual calibration is recommended.

Mónica, Santos; Cláudia, Gomes.

2010-07-01

256

Similarities and Differences between the Pathogenesis and Pathophysiology of Diastolic and Systolic Heart Failure  

OpenAIRE

Pathophysiology of heart failure has been considered to be a damaged state of systolic function of the heart followed by a state of low cardiac output that is, systolic heart failure. Even if systolic function is preserved, left ventricular filling in diastole can be impeded and resulted in elevation of filling pressure and symptoms of heart failure. This kind of heart failure is called diastolic heart failure. Nowadays, diastolic heart failure is referred to as heart failure with preserved e...

Kazuo Komamura

2013-01-01

257

Respuesta de la frecuencia cardiaca y presión arterial en la fase II del programa de rehabilitación cardiaca en Costa Rica / Heart rate and blood pressure response in phase II cardiac rehabilitation program in Costa Rica  

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: Spanish Abstract in spanish Objetivo: describir el comportamiento de la frecuencia cardiaca y presión arterial en pacientes participantes de la fase II del programa de rehabilitación cardiaca del Centro Nacional de Rehabilitación. Métodos: 175 pacientes portadores de enfermedad arterial coronaria admitidos en la fase II del pr [...] ograma de rehabilitación cardiaca, del Centro Nacional de Rehabilitación, entre junio de 2009 y junio de 2011, con una duración de 12 semanas. Se les midió la frecuencia cardiaca y la presión arterial sistólica y diastólica antes del ejercicio y 3 minutos después de finalizado, con seguimiento a 2 años plazo. Resultados: de los 175 pacientes, 134 (76,1%) fueron hombres, con edad promedio de 59,3 años. La frecuencia cardiaca posterior al ejercicio mostró un aumento promedio de 7,9 latidos/ min (13,3%), la presión arterial sistólica una disminución en promedio de 7,80 mmHg (6,98 %) y la presión arterial diastólica mostró un incremento de 2,25 mmHg (3,15 %) el primer mes; 0,71 mmHg (1,24%) el segundo mes y -1,62 mmHg (-1,24%) el tercer mes. A los 2 años se localizó a 121 pacientes de los cuales 10 pacientes sufrieron algún tipo de re-intervención cardiaca y 2 siguen a la espera de un nuevo procedimiento; 88 (72%) se mantienen haciendo ejercicio. No se encontró relación entre el comportamiento de la frecuencia cardiaca y la presión arterial con la incidencia de nuevos eventos o re-intervenciones. Conclusión: el estudio muestra cambios producidos por el ejercicio progresivo en la frecuencia cardiaca y la presión arterial, en un programa de rehabilitación cardiaca fase II. Se encontró un alto porcentaje de adherencia al ejercicio y baja incidencia de eventos a 2 años plazo. Abstract in english Aim: To describe the behavior of heart rate and blood pressure in patients participating in stage II of the Cardiac Rehabilitation Program at the National Rehabilitation Center. Methods: 175 patients with coronary artery disease admitted in phase II of the Cardiac Rehabilitation Program at the Natio [...] nal Rehabilitation Center between June 2009 and June 2011, and a 12-week duration. We recorded heart rate, systolic blood pressure and diastolic blood pressure before and 3 minutes after exercise; with follow-up after 2 years. Results: Out of the 175 patients, 134 (76.1%) were men, with a mean age of 59.3 years old. Heart rate after exercise showed an average increase of 7.9 b/m (13.3%). Systolic blood pressure showed an average decrease of 7.80 mmHg (6.98%) and diastolic blood pressure showed an increase of 2.25 mmHg (3.15%) in the first month, 0.71 mmHg (1.24%) in the second month, and -1.62 mmHg (-1.24%) in the third month. After 2 years we found 121 patients, 10 of them had suffered some kind of cardiac re-intervention and 2 were still waiting for a new procedure; 88 (72%) continue doing exercise. No relationship was found between behavior of heart rate and of blood pressure and the incidence of new cardiac events or re-interventions. Conclusion: This study describes changes in heart rate and blood pressure as a result of progressive exercise in a phase II cardiac rehabilitation program. We found a high percentage of adherence to exercise and a low incidence of events after 2 years.

Manuel, Wong-On; Severita, Carrillo-Barrantes; Milena, Molina-Astúa; Christian, Vargas-Quesada; Sofía, Chaverri Flores.

2014-09-01

258

Analytical Model to Assess Systolic Pressure in Pulmonary Artery in Patients with Bronchial Asthma  

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Full Text Available The aim of the investigation is to study the peculiarities of pulmonary circulatory dynamics in patients with bronchial asthma, develop and apply an analytical model of correlation between systolic pressure in pulmonary artery and respiratory function (RF values. Materials and Methods. 112 patients with severe bronchial asthma (BA were examined. Physical examination, RF and echo Doppler cardiography were performed in all patients. Results. The presence of obstructive syndrome was confirmed when performing RF investigation in patients with severe BA. Severe pulmonary hypertension was also revealed in patients with severe BA. The pressure in pulmonary artery was increasing in bronchial obstruction progression and the reduction of forced expiratory volume per second (FEV1 that was represented by negative significant correlation dependence between the given parameters (r=–0.48; ?=0.005. There was developed an analytical model of dependence between FEV1 and the level of systolic pressure in pulmonary artery based on linear regression analysis. The model enables to assess approximately the main parameters of pulmonary circulatory dynamics in BA patients in clinical practice. Conclusion. Pulmonary hypertension revealed in 53.2% of BA patients has moderate functional character. One of the determining factors of pulmonary hypertension in bronchial asthma is bronchial obstruction. There is strong correlation and analytical interrelation between RF and pulmonary circulatory dynamics values.

S.S. Plastinina

2011-12-01

259

Arterial pressure responses to increasing interstitial potassium in hindlimb muscle of dogs.  

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Static contraction of hindlimb skeletal muscle is known to increase reflexly arterial pressure and heart rate. Potassium is known to be released by the working muscle and is thought to activate the afferents responsible for the reflex cardiovascular responses to muscular contraction. However, it is not known whether potassium, at interstitial concentrations within the range observed during static contraction, is capable of stimulating these afferents. Thus we injected potassium into the gracilis artery of chloralose-anesthetized dogs while we measured interstitial potassium concentrations in the gracilis muscle with potassium-selective electrodes. In 16 dogs, we found that potassium injections, which increased interstitial potassium concentrations by 4.7 +/- 0.3 mM, increased mean arterial pressure by 18 +/- 3 mmHg and heart rate by 12 +/- 8 beats/min; cutting the obturator nerve abolished these increases. These heart rate and blood pressure responses were of short duration (20 +/- 7 s), even though interstitial potassium remained elevated for a period of several minutes. In 5 of the 16 dogs, static contraction of the gracilis muscle for 60 s increased interstitial potassium concentration by 4.3 +/- 0.3 mM. Our data are consistent with the hypothesis that potassium plays a role in causing the reflex cardiovascular responses to static muscular contraction. PMID:6437247

Rybicki, K J; Kaufman, M P; Kenyon, J L; Mitchell, J H

1984-10-01

260

Echocardiographic Characterization of Postnatal Development in Mice with Reduced Arterial Elasticity  

Science.gov (United States)

Purpose Decreased expression of elastin results in smaller, less compliant arteries and high blood pressure. In mice, these differences become more significant with postnatal development. It is known that arterial size and compliance directly affect cardiac function, but the temporal changes in cardiac function have not been investigated in elastin insufficient mice. The aim of this study is to correlate changes in arterial size and compliance with cardiac function in wildtype (WT) and elastin haploinsufficient (Eln+/?) mice from birth to adulthood. Methods Ultrasound scans were performed at the ages of 3, 7, 14, 21, 30, 60, and 90 days on male and female WT and Eln+/? mice. 2-D ultrasound and pulse wave Doppler images were used to measure the dimensions and function of the left ventricle (LV), ascending aorta and carotid arteries. Results Eln+/? arteries are smaller and less compliant at most ages, with significant differences from WT as early as 3 days old. Surprisingly, there are no correlations (R2 < 0.2) between arterial size and compliance with measures of LV hypertrophy or systolic function. There are weak correlations (0.2 < R2 < 0.5) between arterial size and compliance with measures of LV diastolic function. Conclusions Eln+/? mice have similar cardiac function to WT throughout postnatal development, demonstrating the remarkable ability of the developing cardiovascular system to adapt to mechanical and hemodynamic changes. Correlations between arterial size and compliance with diastolic function show that these measures may be useful indicators of early diastolic dysfunction. PMID:23646094

Le, Victoria P.; Wagenseil, Jessica E.

2012-01-01

261

Subclavian steal syndrome presenting as recurrent pulmonary oedema associated with acute left ventricular diastolic dysfunction.  

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Subclavian steal syndrome typically presents as angina in patients with internal mammary artery grafts. Atypical clinical presentations have been rarely described. We report an unusual case of subclavian steal syndrome presenting as pulmonary oedema with acute left ventricular diastolic dysfunction and preserved ejection fraction in a patient with internal mammary artery graft and severe stenosis of the proximal left subclavian artery. After successful angioplasty and stenting of subclavian artery, the patient remained asymptomatic for six months, but then experienced acute diastolic dysfunction and recurrent pulmonary oedema associated with critical subclavian in-stent restenosis with stent deformation. This report points out that, in patients with internal mammary-to-LAD grafts, subclavian steal syndrome may present as acute left ventricular diastolic dysfunction and pulmonary oedema even in the presence of normal ejection fraction. PMID:23036888

Mangialavori, Giuseppe; Ballo, Piercarlo; Michelagnoli, Stefano; Ercolini, Leonardo; Barbanti, Enrico; Passuello, Franco; Abbondanti, Alessandro; Consoli, Lorenzo; Chechi, Tania; Fibbi, Veronica; Nannini, Marco; Chiodi, Leandro; Zuppiroli, Alfredo

2013-01-01

262

Carotid artery disease and low cerebral perfusion pressure: symptomatology, operative risk and outcome.  

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Direct internal carotid artery blood pressure measurements in patients undergoing carotid endarterectomy identified 49 patients, among 239 consecutive cases (21%), who had a reduction in perfusion pressure of 20% or more. The clinical history, objective findings and angiographic data were compared with those of a control group of a further 49 patients selected from the remaining patients operated on over the same period. The two groups were compared for short- and long-term outcome of surgery. We were unable to delineate a symptomatic neurological profile that identified patients with low perfusion pressures. Surgery in patients with low perfusion pressures seemed to be associated with an increased complication rate (12% versus 4%), although this was not statistically significant. Definite postoperative improvements in persisting neurological deficits were observed only in one patient. Long-term results were equal in the two groups with an annual stroke risk of 3%. PMID:1970624

Schroeder, T; Utzon, N P; Aabech, J; Sillesen, H; Sørensen, P S; Engell, H C

1990-03-01

263

Reverse end-diastolic flow in a fetus with a rare liver malformation: a case report  

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Full Text Available Abstract Introduction We describe a case of early and persistent reverse end-diastolic flow in the middle cerebral artery in a fetus with severe ascites. These features are associated with a rare liver malformation known as ductal plate malformation. Case presentation A 28-year-old Caucasian woman was referred to our high-risk obstetric unit at 24 weeks' gestation for fetal ascites detected during a routine ultrasound examination. During her hospitalization we performed medical investigations, including a fetal paracentesis, to detect the etiology of fetal ascites. The cause of fetal ascites (then considered non-immune or idiopathic was not evident, but a subsequent ultrasound examination at 27 weeks' gestation showed a reverse end-diastolic flow in the middle cerebral artery without any other Doppler abnormalities. A cesarean section was performed at 28 weeks' gestation because of the compromised fetal condition. An autopsy revealed a rare malformation of intrahepatic bile ducts known as ductal plate malformation. Conclusion Persistent reverse flow in the middle cerebral artery should be considered a marker of adverse pregnancy outcome. We recommend careful ultrasound monitoring in the presence of this ultrasonographic sign to exclude any other cause of increased intracranial pressure. To better understand the nature of these ultrasonographic signs, additional reports are deemed necessary. In fact in our case, as confirmed by histopathological examination, the fetal condition was extremely compromised due to failure of the fetal liver. Ductal plate malformation altered the liver structures causing hypoproteinemia and probably portal hypertension. These two conditions therefore explain the severe hydrops that compromised the fetal situation.

La Torre Renato

2011-01-01

264

Application of Static Pressure Change in Estimation of Elastic Parameters of Rabbit’s Artery by Doppler Ultrasound  

OpenAIRE

Backgrounds/Objectives : Noninvasive evaluation of elastic properties of vessel wall is hampered by the absence of methods to directly asse ss local elasticity. In order to invasively record the static pressure of carotid artery dur ing cardiac cycle in rabbit s and compare it with noninvasive technique, T–shaped tubes have been designed and constructed and calibrated. A noninvasive method to measure static pressure in arteries and finally estimate the elasticity of vessels is provided. Mat...

Nikanjam, N.; Mokhtari Dizaji, M.; Saberi, H.

2005-01-01

265

Hydrostatic Pressure Independently Increases Elastin and Collagen Co-expression in Small-diameter Engineered Arterial Constructs  

OpenAIRE

Prior studies have demonstrated that smooth muscle cell (SMC) proliferation, migration, and extracellular matrix production increase with hydrostatic pressure in vitro. We have engineered highly compliant small-diameter arterial constructs by culturing primary adult arterial SMCs under pulsatile perfusion on tubular, porous, elastomeric scaffolds composed of poly(glycerol sebacate) (PGS). This study investigates the effect of hydrostatic pressure on the biological and mechanical properties of...

Crapo, Peter M.; Wang, Yadong

2011-01-01

266

Simultaneous recording of continuous arterial pressure, heart rate, and ST segment in ambulant patients with stable angina pectoris.  

OpenAIRE

Simultaneous and accurate recording of arterial blood pressure and ST segment changes is fraught with technical difficulties. We have developed a new system to enable accurate reproduction of the electrocardiogram and intra-arterial blood pressure, using a transducer/perfusion unit conventionally used to study hypertensive subjects, linked to a frequency modulated tape recorder. Detailed methods of digital analysis have been developed to process the data. This system has been used to study 22...

Davies, A. B.; Bala Subramanian, V.; Cashman, P. M.; Raftery, E. B.

1983-01-01

267

La hipertensión arterial como causa de mortalidad / The high blood pressure as a cause of death  

Scientific Electronic Library Online (English)

Full Text Available SciELO Cuba | Language: Spanish Abstract in spanish Introducción: la hipertensión arterial constituye el factor de riesgo mayor sobre la morbilidad y mortalidad de causa cardiovascular, estimado a través de los certificados de defunción. Objetivo: evaluar la repercusión de este factor de riesgo como causa de mortalidad. Métodos: se realizó un estudio [...] descriptivo, retrospectivo de los pacientes fallecidos con hipertensión arterial entre el 2002 y 2007. Las variables estudiadas fueron: edad, sexo, color de la piel, causa directa de muerte, causa básica de muerte, causa contribuyente de muerte y correlación clínica/patológica. Resultados: se encontró que el 9,1 % de los fallecidos eran hipertensos, el grupo de edad más afectado fue el de 65 a 74 años (23,4 %) y la edad promedio fue de 65 años. En 248 fallecidos existió coincidencia diagnóstica total en la causa directa de muerte (74,6 %) y en 236 en la causa básica de muerte (71,0 %). La hipertensión arterial constituyó la causa básica de muerte en el 59,3 % y la causa contribuyente de muerte en el 18,97 %. En más de la mitad de los casos, la hipertensión arterial participó en los mecanismos de muerte a través de la causa básica de muerte y causa contribuyente de muerte. Conclusiones: la hipertensión arterial constituye un determinante causal en la mortalidad y progresión del daño vascular aterosclerótico. Abstract in english Introduction: high blood pressure is a major risk factor on the morbidity and mortality of cardiovascular origin according to the death certificate, Objective: to assess the repercussion of this risk factor as cause of death. Methods: a retrospective and descriptive study was conducted in patients d [...] eceased with high blood pressure between 2002 and 2007. Study variables were: age, sex, skin color, direct cause of death, basic cause of death, contributing cause of death and clinical/pathological correlation. Results: there found that the 9.1 % of deceases were hypertensive, the more involved age group was that of 65-74 years (23.4 %) and the mean age was of 65 years. In 248 deceased there was a total diagnostic coincidence in relation to the direct cause of death (74.6 %) and in 236 deceased in the basic cause of death (71.0 %). High blood pressure was the basic cause of death in the 59.3 % and the contributing cause of death in the 18.97 %. In more than a half of cases, high blood pressure was involved in the death mechanisms through the basic and the contributing cause of death. Conclusions: High blood pressure is a causal determinant factor in the mortality and the progression of atherosclerotic vascular damage.

Vania, Ferrer Santos; Mileidys, Domínguez Hernández; Ariadna, Méndez Rosabal.

2011-06-01

268

Blood pressure decrease prior to initiating pharmacological therapy in nonemergent hypertension.  

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In order to characterize the decrease in blood pressure that occurs in the emergency department (ED) setting in cases of nonemergent hypertension before beginning pharmacological therapy, 94 consecutive cases of hypertension seen at the University of Illinois Hospital were reviewed. Each patient in the analysis had a triage blood pressure recorded by the nursing staff and second blood pressure reading taken between 10 minutes and 2 hours after the triage pressure before pharmacological therapy was begun. Patients with diastolic pressures less than 90 mm Hg were excluded, as were patients with acute end-organ pathology secondary to hypertension. In the remaining 54 cases, the mean arterial pressure fell by 6% (P less than .003), the systolic pressure fell by 6% (P less than .022), and the diastolic pressure fell by 6.4% (P less than .003), suggesting that in nonemergent hypertension, a significant decrease in blood pressure occurs in the ED before pharmacological therapy is begun. The blood pressure decrease was not statistically different when sex and age were considered, but when patients were grouped into those with diastolic pressures between 90 mm Hg and 114 mm Hg and those with diastolic pressures greater than or equal to 115 mm Hg, there was a statistically significant decrease in systolic, diastolic, and mean arterial pressures only in patients with diastolic pressures greater than or equal to 115 mm Hg. Our findings suggest that patients with nonemergent hypertension do not always require immediate and aggressive pharmacological intervention in the ED setting and are best observed for a short period and then reassessed before beginning pharmacological therapy. PMID:2293829

Lebby, T; Paloucek, F; Dela Cruz, F; Leikin, J B

1990-01-01

269

Geometry-based pressure drop prediction in mildly diseased human coronary arteries.  

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Pressure drop (?p) estimations in human coronary arteries have several important applications, including determination of appropriate boundary conditions for CFD and estimation of fractional flow reserve (FFR). In this study a ?p prediction was made based on geometrical features derived from patient-specific imaging data. Twenty-two mildly diseased human coronary arteries were imaged with computed tomography and intravascular ultrasound. Each artery was modelled in three consecutive steps: from straight to tapered, to stenosed, to curved model. CFD was performed to compute the additional ?p in each model under steady flow for a wide range of Reynolds numbers. The correlations between the added geometrical complexity and additional ?p were used to compute a predicted ?p. This predicted ?p based on geometry was compared to CFD results. The mean ?p calculated with CFD was 855±666Pa. Tapering and curvature added significantly to the total ?p, accounting for 31.4±19.0% and 18.0±10.9% respectively at Re=250. Using tapering angle, maximum area stenosis and angularity of the centerline, we were able to generate a good estimate for the predicted ?p with a low mean but high standard deviation: average error of 41.1±287.8Pa at Re=250. Furthermore, the predicted ?p was used to accurately estimate FFR (r=0.93). The effect of the geometric features was determined and the pressure drop in mildly diseased human coronary arteries was predicted quickly based solely on geometry. This pressure drop estimation could serve as a boundary condition in CFD to model the impact of distal epicardial vessels. PMID:24746019

Schrauwen, J T C; Wentzel, J J; van der Steen, A F W; Gijsen, F J H

2014-06-01

270

Effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome  

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AIM: To study the effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome. METHODS: Garlic powder in a capsule form was given to 15 children with hepatopulmonary syndrome (confirmed by contrast echocardiography) at the dosage of 1 g/1.73 m2 per day. Patients were evaluated clinically and by arterial blood gas every four weeks. RESULTS: The garlic capsule was administered to 15 patients with hepatopulmonary syndrome. There were 10 boys and 5 girls with a mean age of 9.4 ± 3.9 years. The underlying problems were biliary tract atresia (4 patients), autoimmune hepatitis (4 patients), cryptogenic cirrhosis (4 patients) and presinusoidal portal hypertension (3 patients). Eight patients (53.3%) showed an increase of 10 mmHg in their mean arterial oxygen pressure. The baseline PaO2 was 65.6 ± 12.1 mmHg in the responder group and 47.1 ± 11.2 mmHg in non-responder group. At the end of treatment the mean PaO2 in responders and non-responders was 92.2 ± 7.75 mmHg and 47.5 ± 11.87 mmHg, respectively (P < 0.01). CONCLUSION: Garlic may increase oxygenation and improve dyspnea in children with hepatopulmonary syndrome. PMID:16688838

Sani, Mehri Najafi; Kianifar, Hamid Reza; Kianee, Abdolrazagh; Khatami, Gholamreza

2006-01-01

271

Systolic and mean pulmonary artery pressures: are they interchangeable in patients with pulmonary hypertension?  

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Pulmonary hypertension (PH) is a common complication of numerous diseases, including left-sided heart diseases and chronic lung diseases and/or hypoxia, where PH is associated with exercise limitation and a worse prognosis. Other forms of PH include pulmonary arterial hypertension (PAH), chronic thromboembolic PH (CTEPH), and PH with unclear multifactorial mechanisms. Over the past decade, it has been documented that systolic pulmonary artery pressure (sPAP) may help estimate mean pulmonary artery pressure (mPAP) in adults with high accuracy and reasonably good precision (mPAP = 0.61 sPAP + 2 mm Hg). This strong linear relationship between sPAP and mPAP was unexpected from a classic physiologic point of view. Consistent results have been obtained from independent teams using either high-fidelity micromanometer-tipped PA catheters or fluid-filled catheters. Overall, the strong link between sPAP and mPAP has been documented over a wide range of PAPs, heart rate, cardiac output, wedge pressure, and causes of PH, during changes in posture and activity, and irrespective of patient's sex, age, and BMI. A review of available invasive data confirms that patients with CTEPH and idiopathic PAH matched for their mPAP exhibit essentially similar sPAP. Pressure redundancy may be explained by the dependence of PA compliance upon mPAP. The 25 mm Hg threshold used to define PH accurately corresponds to an sPAP of 38 mm Hg. Although the limits of the echocardiographic estimation of sPAP are widely documented, results from invasive studies may furnish an evidence-based sPAP-derived mPAP value, potentially useful in the multiparameter echocardiographic approach currently used to diagnose and follow patients with PH. PMID:25846528

Chemla, Denis; Humbert, Marc; Sitbon, Olivier; Montani, David; Hervé, Philippe

2015-04-01

272

Variaciones de riesgo en valores de tensión arterial en pacientes hipertensos durante procedimientos odontológicos / Risk changes in blood pressure in hypertensive patients during dental procedures  

Scientific Electronic Library Online (English)

Full Text Available Introducción: Las variaciones de Tensión Arterial (TA) de origen fisiológico son frecuentes; sin embargo, los procedimientos durante la consulta odontológica podrían generar variaciones a valores de riesgo de TA que pueden alterar el estado sistémico, o generar complicaciones médicas que comprometen [...] la integridad del paciente. Objetivo: Identificar factores que generan variaciones de riesgo de la Tensión Arterial durante los procedimientos odontológicos en pacientes hipertensos y no hipertensos. Materiales y métodos: Se diseñó un estudio observacional descriptivo, en 108 pacientes. Se evaluaron tanto hipertensos como no hipertensos, incluidos por un muestreo probabilístico por conglomerados; se evaluaron variables sociodemográficas, presión arterial antes, durante y después del procedimiento, factores de riesgo cardiovascular y aquellas dependientes del procedimiento. Los datos se procesaron en el programa SPSS 21, utilizando medidas de tendencia central y dispersión, desviación estándar (DE) e intervalos de confianza (IC), frecuencias, chi 2, T test, diferencia de medias, ANOVA de una vía y medidas repetidas. Resultados: La edad media fue 62,3 años con DE 12,5 años; 42(38,9%) fueron no hipertensos y 66(61,1%) hipertensos. Las variaciones de presión sistólica mayor a 20mmHg y diastólica mayor a 10mmHg se presentaron en mayor porcentaje en los hipertensos con control errático. Así mismo las variaciones fueron superiores en mujeres y en procedimientos sin uso de anestésico. Según el tipo de hipertensión, se encontraron diferencias entre el grupo de sanos con los grupos control errático, mal control y sin control. Al aplicar un modelo lineal de medidas repetidas, se encontraron diferencias en las tres mediciones en los diferentes tipos de hipertensión. Conclusiones: Los factores relacionados a variaciones de riesgo fueron el control errático, sexo femenino y duración del procedimiento. Abstract in english Introduction: Physiologic changes in blood pressure are frequent, nevertheless dental procedures could trigger an increase in blood pressure, which may alter the state or even generate systemic vascular injury or medical complications, that compromise patient integrity. Objectives: To identify facto [...] rs, which produce risk variations of blood pressure levels during dental procedures in hypertensive and no hypertensive patients. Materials and Methods: A descriptive study was made in 108 patients; including hypertensive and non-hypertensive patients. Sociodemographic variables were assessed, blood pressure values; before, during and after procedure, cardiovascular risk factors and those dependent of the procedure. Patients were selected using the cluster probability method. The data were processed at SPSS 21, using central tendency measures and dispersion, standard deviation and confidence interval, frequencies, chi2, T test, mean difference, one-way ANOVA and repeated measures. Results: The mean age was 62.3 years with SD 12,5 years, 42 (38.9%) without hypertension and 66(61.1%) hypertensive patients. Changes in systolic pressure greater than 20mmHg in systolic and 10mmHg in diastolic, was present in greater percentage of hypertensive patients with erratic control, in women and procedures without the use of anesthetic. Depending on the type of hypertension, differences were found between the group of healthy control, erratic control group, poorly controlled and uncontrolled group. By applying a linear model repeated measures, we found differences in the measurements of arterial pressure in different types of hypertension. Conclusions The factors related with risk variations in blood pressure occurred in erratic control hypertension patients, women and duration of the procedure.

Gloria C, Aranzazu-Moya; Ronald Y, Delgado-Jaimes; María P, Pieschacón-Gutierrez.

2014-08-01

273

Evaluation of left ventricular diastolic function of CAD patients by radionuclide ventriculography  

International Nuclear Information System (INIS)

To analyze the early and late left ventricular diastolic function in coronary artery disease (CAD), technetium-99m gated equilibrium radionuclide ventriculography was performed in 27 patients with CAD, including 8 old myocardial infarction (group GM), 19 non-myocardial infarction (group GN), and 12 control subjects (group G1). Parameters of diastolic function was obtained from second derivative analysis of time-activity curve. In GM group, indexes of systolic and diastolic function was significantly depressed than those of GN and G1 group (P<0.0001)

274

Balloon Occlusion Test of the Internal Carotid Artery: Correlation with Stump Pressure and 99mTc-HMPAO SPECT  

International Nuclear Information System (INIS)

Purpose: To evaluate the correlation of stump pressure during balloon occlusion test and relative cerebral blood flow (relative CBF) as measured by 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) single-photon emission computed tomography (SPECT) after test occlusion.Material and Methods: Balloon occlusion test of the internal carotid artery (ICA) was performed in 25 patients. The count ratio of occluded hemisphere to non-occluded hemisphere was calculated on 99mTc-HMPAO SPECT. The ratio of mean stump pressure to mean arterial pressure during carotid occlusion during the balloon occlusion test was compared with the count ratio of 99mTc-HMPAO SPECT. Results: Two patients failed to tolerate even brief carotid occlusion. The other 23 patients showed no ischemic deficit during occlusion of the ICA. In 13 of these 23 patients, the ratios of mean stump pressure to mean arterial pressure were more than 50%, and the count ratios on SPECT were more than 85%. In 10 of 23 patients, the ratios of mean stump pressure to mean arterial pressure were less than 50%, and the count ratios on SPECT were variable. Conclusion: Maintenance of a mean stump pressure of 50% or more of the mean systemic pressure during test occlusion indicates adequate cerebral blood flow during carotid occlusion

275

Balloon Occlusion Test of the Internal Carotid Artery: Correlation with Stump Pressure and {sup 99m}Tc-HMPAO SPECT  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To evaluate the correlation of stump pressure during balloon occlusion test and relative cerebral blood flow (relative CBF) as measured by {sup 99m}Tc-hexamethylpropyleneamine oxime ({sup 99m}Tc-HMPAO) single-photon emission computed tomography (SPECT) after test occlusion.Material and Methods: Balloon occlusion test of the internal carotid artery (ICA) was performed in 25 patients. The count ratio of occluded hemisphere to non-occluded hemisphere was calculated on {sup 99m}Tc-HMPAO SPECT. The ratio of mean stump pressure to mean arterial pressure during carotid occlusion during the balloon occlusion test was compared with the count ratio of {sup 99m}Tc-HMPAO SPECT. Results: Two patients failed to tolerate even brief carotid occlusion. The other 23 patients showed no ischemic deficit during occlusion of the ICA. In 13 of these 23 patients, the ratios of mean stump pressure to mean arterial pressure were more than 50%, and the count ratios on SPECT were more than 85%. In 10 of 23 patients, the ratios of mean stump pressure to mean arterial pressure were less than 50%, and the count ratios on SPECT were variable. Conclusion: Maintenance of a mean stump pressure of 50% or more of the mean systemic pressure during test occlusion indicates adequate cerebral blood flow during carotid occlusion.

Kato, K.; Tomura, N.; Takahashi, S.; Sakuma, I.; Sasaki, K.; Kitani, H.; Watarai, J. [Akita Univ. School of Medicine (Japan). Dept. of Radiology

2006-12-15

276

Monounsaturated fatty acid, carbohydrate intake, and diabetes status are associated with arterial pulse pressure  

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Full Text Available Abstract Background Diabetes is a global epidemic. Cardiovascular disease (CVD is one of the most prevalent consequences of diabetes. Nutrition is considered a modifiable risk factor for CVD, particularly for individuals with diabetes; albeit, there is little consensus on the role of carbohydrates, proteins and fats for arterial health for persons with or without diabetes. In this study, we examined the association of macronutrients with arterial pulse pressure (APP, a surrogate measure of arterial health by diabetes status and race. Methods Participants were 892 Mexican Americans (MA, 1059 Black, non-Hispanics (BNH and 2473 White, non-Hispanics (WNH with and without diabetes of a weighted sample from the National Nutrition and Health Examination Survey (NHANES 2007-2008. The cross-sectional analysis was performed with IBM-SPSS version 18 with the complex sample analysis module. The two-year sample weight for the sub-sample with laboratory values was applied to reduce bias and approximate a nationally, representative sample. Arterial stiffness was assessed by arterial pulse pressure (APP. Results APP was higher for MA [B = 0.063 (95% CI 0.015 to 0.111, p = 0.013] and BNH [B = 0.044 (95% CI 0.006 to 0.082, p = 0.018] than WNH, controlling for diabetes, age, gender, body mass index (BMI, fiber intake, energy intake (Kcal and smoking. A two-way interaction of diabetes by carbohydrate intake (grams was inversely associated with APP [B = -1.18 (95% CI -0.178 to -0.058, p = 0.001], controlling for race, age, gender, BMI, Kcal and smoking. BNH with diabetes who consumed more mono-unsaturated fatty acids (MUFA than WNH with diabetes had lower APP [B = -0.112 (95%CI-0.179 to -0.045, p = 0.003] adjusting for saturated fatty acids, Kcal, age, gender, BMI and smoking. Conclusion Higher MUFA and carbohydrate intake for persons with diabetes reflecting lower APP may be due to replacement of saturated fats with CHO and MUFA. The associations of APP with diabetes, race and dietary intake need to be confirmed with intervention and prospective studies. Confirmation of these results would suggest that dietary interventions for minorities with diabetes may improve arterial health.

Vaccaro Joan A

2011-11-01

277

Evaluation of a new arterial pressure-based cardiac output device requiring no external calibration  

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Full Text Available Abstract Background Several techniques have been discussed as alternatives to the intermittent bolus thermodilution cardiac output (COPAC measurement by the pulmonary artery catheter (PAC. However, these techniques usually require a central venous line, an additional catheter, or a special calibration procedure. A new arterial pressure-based cardiac output (COAP device (FloTrac™, Vigileo™; Edwards Lifesciences, Irvine, CA, USA only requires access to the radial or femoral artery using a standard arterial catheter and does not need an external calibration. We validated this technique in critically ill patients in the intensive care unit (ICU using COPAC as the method of reference. Methods We studied 20 critically ill patients, aged 16 to 74 years (mean, 55.5 ± 18.8 years, who required both arterial and pulmonary artery pressure monitoring. COPAC measurements were performed at least every 4 hours and calculated as the average of 3 measurements, while COAP values were taken immediately at the end of bolus determinations. Accuracy of measurements was assessed by calculating the bias and limits of agreement using the method described by Bland and Altman. Results A total of 164 coupled measurements were obtained. Absolute values of COPAC ranged from 2.80 to 10.80 l/min (mean 5.93 ± 1.55 l/min. The bias and limits of agreement between COPAC and COAP for unequal numbers of replicates was 0.02 ± 2.92 l/min. The percentage error between COPAC and COAP was 49.3%. The bias between percentage changes in COPAC (?COPAC and percentage changes in COAP (?COAP for consecutive measurements was -0.70% ± 32.28%. COPAC and COAP showed a Pearson correlation coefficient of 0.58 (p PAC and ?COAP was 0.46 (p Conclusion Although the COAP algorithm shows a minimal bias with COPAC over a wide range of values in an inhomogeneous group of critically ill patients, the scattering of the data remains relative wide. Therefore, the used algorithm (V 1.03 failed to demonstrate an acceptable accuracy in comparison to the clinical standard of cardiac output determination.

Amann Matthias

2007-11-01

278

Ex Vivo and in Silico Study of Human Common Carotid Arteries Pressure Response in Physiological and Inverted State  

Science.gov (United States)

Arterial walls are a multilayer structures with nonlinear material characteristics. Furthermore, residual stresses exist in unloaded state (zero-pressure condition) and they affect arterial behavior. To investigate these phenomena a number of theoretical and numerical studies were performed, however no experimental validation was proposed and realized yet. We cannot get rid of residual stresses without damaging the arterial segment. In this paper we propose a novel experiment to validate a numerical model of artery with residual stresses. The inspiration for our study originates from experiments made by Dobrin on dogs' arteries (1999). We applied the idea of turning the artery inside out. After such an operation the sequence of layer is reversed and the residual stresses are re-ordered. We performed several pressure-inflation tests on human Common Carotid Arteries (CCA) in normal and inverted configurations. The nonlinear responses of arterial behavior were obtained and compared to the numerical model. Computer simulations were carried out using the commercial software which applied the finite element method (FEM). Then, these results were discussed.

Piechna, A.; Cie?licki, K.; Lombarski, L.; Ciszek, B.

2015-02-01

279

Intervenções em Dieta e Pressão Arterial na América Latina - Revisão Sistemática e Meta-Análise / Dietary Interventions and Blood Pressure in Latin America - Systematic Review and Meta-Analysis  

Scientific Electronic Library Online (English)

Full Text Available Fundamento: Pressão arterial elevada é o principal fator de risco para doenças cardiovasculares. Baixos índices de controle da pressão arterial em populações latino-americanas reforçam a necessidade de reunir evidências sobre terapias eficazes. Objetivo: Avaliar o efeito das intervenções de mo [...] dificações de dietas sobre pressão arterial em populações latino-americanas. Métodos: Revisão sistemática. Foram pesquisadas diversas bases de dados (MEDLINE-PubMed, Embase, Cochrane Library, CINAHL, Web of Science, Scopus, SciELO, LILACS e BVS) e realizada busca manual até abril de 2013. Foram incluídos estudos paralelos de intervenções em dieta em populações adultas da América Latina reportando pressão arterial (em mmHg) antes e após a intervenção. Resultados: Dos 405 estudos encontrados, 10 ensaios clínicos randomizados foram incluídos e divididos em 3 subgrupos, de acordo com a dieta proposta como intervenção. Houve redução não significativa da pressão arterial sistólica nos subgrupos de substituição mineral -4,82 (IC 95%: -11,36 a 1,73 mmHg) e padrões complexos -3,17 (IC 95%: -7,62 a 1,28 mmHg). Para a pressão arterial diastólica, com exceção do subgrupo de dietas hiperproteicas, todos os subgrupos apresentaram redução significativa, com -4,66 (IC 95%: -9,21 a -0,12 mmHg) e -4,55 (IC 95%: -7,04 a -2,06 mmHg) para substituição mineral e padrões complexos, respectivamente. Conclusão: A evidência disponível sobre os efeitos de alterações de dieta na pressão arterial em populações latino-americanas indica um efeito homogêneo, porém não significativo, para pressão arterial sistólica. Estudos maiores e com maior rigor metodológico são necessários para construção de evidência robusta. Abstract in english Background: High blood pressure is the major risk factor for cardiovascular disease. Low blood pressure control rates in Latin American populations emphasize the need for gathering evidence on effective therapies. Objective: To evaluate the effects of dietary interventions on blood pressure in [...] Latin American populations. Methods: Systematic review. Electronic databases (MEDLINE/PubMed, Embase, Cochrane Library, CINAHL, Web of Science, Scopus, SciELO, LILACS and VHL) were searched and manual search for studies published up to April 2013 was performed. Parallel studies about dietary interventions in Latin American adult populations assessing arterial blood pressure (mm Hg) before and after intervention were included. Results: Of the 405 studies identified, 10 randomized controlled trials were included and divided into 3 subgroups according to the proposed dietary intervention. There was a non-significant reduction in systolic blood pressure in the subgroups of mineral replacement (-4.82; 95% CI: -11.36 to 1.73) and complex pattern diets (-3.17; 95% CI: -7.62 to 1.28). Regarding diastolic blood pressure, except for the hyperproteic diet subgroup, all subgroups showed a significant reduction in blood pressure: -4.66 mmHg (95% CI: -9.21 to -0.12) and -4.55 mmHg (95% CI: -7.04 to -2.06) for mineral replacement and complex pattern diets, respectively. Conclusion: Available evidence on the effects of dietary changes on blood pressure in Latin American populations indicates a homogeneous effect of those interventions, although not significant for systolic blood pressure. Samples were small and the quality of the studies was generally low. Larger studies are required to build robust evidence.

Caroline Cantalejo, Mazzaro; Flávia Caroline, Klostermann; Bruna Olandoski, Erbano; Nicolle Amboni, Schio; Luiz César, Guarita-Souza; Marcia, Olandoski; José Rocha, Faria-Neto; Cristina Pellegrino, Baena.

2014-04-29

280

Pharmacodynamic and pharmacoeconomic aspects of application of antihypertensive preparations of various groups in patients with arterial hypertension  

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Full Text Available At the background of the therapy for 3 months with Perindopril, Telmisartan and Bisoprolol, the patients with arterial hypertension were noted to decrease systolic and diastolic arterial pressure. The preparations under investigation had different effects on electrolyte metabolism. Therapy with Telmisartan turned out to have the least effect on electrolyte metabolism. Microalbuminuria is a risk factor in patients with arterial hypertension and may influence on the basic blood electrolyte balance. Bisoprolol should be recommended as the most preferable therapy for arterial hypertension from the pharmacoeconomic point of view. In order to control morning systolic arterial pressure the preference should be given to Perindopril, while for controlling evening systolic arterial pressure the preference should be given to Telmisartan

Kurkina T.V.

2010-09-01

281

The haemodynamic effect of intravenous flecainide acetate in patients with coronary artery disease  

OpenAIRE

Flecainide acetate has been shown to be a potent antiarrhythmic agent which is active for more than 8 h, whether given intravenously or orally. However, the negative inotropic effect demonstrated in animal studies could hamper the potential clinical utility of the drug. Ten patients with coronary artery disease but without cardiac failure were given intravenous flecainide (2 mg/kg). Stroke index (SI), left ventricular systolic pressure (LVP), end diastolic pressure (EDP) and LV contractility ...

Serruys, P. W. J. C.; Vanhaleweyk, G.; Brand, M. J. B. M. Den; Verdouw, P. D.; Lubsen, J.; Hugenholtz, P. G.

1983-01-01

282

Arterial line pressure control enhanced extracorporeal blood flow prescription in hemodialysis patients  

OpenAIRE

Abstract Background In hemodialysis, extracorporeal blood flow (Qb) recommendation is 300–500 mL/min. To achieve the best Qb, we based our prescription on dynamic arterial line pressure (DALP). Methods This prospective study included 72 patients with catheter Group 1 (G1), 1877 treatments and 35 arterio-venous (AV) fistulae Group 2 (G2), 1868 treatments. The dialysis staff was trained to prescribe Qb sufficient to obtain DALP between -200 to -250 mmHg. We measured ionic clearance (IK: mL/mi...

Rosales Laura; Flores Nelly; De-La-Cruz Guadalupe; Magaña Salvador; Herrera–Felix Juan P; Mariscal Alfonso; Mora-Bravo Franklin G; Franco Martha; Pérez-Grovas Héctor

2008-01-01

283

Clinical characterization and survival of patients with borderline elevation in pulmonary artery pressure  

OpenAIRE

Normal resting mean pulmonary artery pressure (PAP) is 8–20 mmHg. Pulmonary hypertension is defined as mean PAP of ?25 mmHg. Borderline PAP levels of 21–24 mmHg are of unclear significance. We sought to determine the clinical characteristics and survival of subjects with mean PAP of 21–24 mmHg. We examined 1,491 patients enrolled in the Cleveland Clinic Pulmonary Hypertension Registry between February 1990 and May 2012 with baseline right heart catheterization. The relationship betwee...

Heresi, Gustavo A.; Minai, Omar A.; Tonelli, Adriano R.; Hammel, Jeffrey P.; Farha, Samar; Parambil, Joseph G.; Dweik, Raed A.

2013-01-01

284

Optic Nerve Head Blood Flow Autoregulation during Changes in Arterial Blood Pressure in Healthy Young Subjects  

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Aim In the present study the response of optic nerve head blood flow to an increase in ocular perfusion pressure during isometric exercise was studied. Based on our previous studies we hypothesized that subjects with an abnormal blood flow response, defined as a decrease in blood flow of more than 10% during or after isometric exercise, could be identified. Methods A total of 40 healthy subjects were included in this study. Three periods of isometric exercise were scheduled, each consisting of 2 minutes of handgripping. Optic nerve head blood flow was measured continuously before, during and after handgripping using laser Doppler flowmetry. Blood pressure was measured non-invasively in one-minute intervals. Intraocular pressure was measured at the beginning and the end of the measurements and ocular perfusion pressure was calculated as 2/3*mean arterial pressure –intraocular pressure. Results Isometric exercise was associated with an increase in ocular perfusion pressure during all handgripping periods (p < 0.001). By contrast no change in optic nerve head blood flow was seen. However, in a subgroup of three subjects blood flow showed a consistent decrease of more than 10% during isometric exercise although their blood pressure values increased. In addition, three other subjects showed a consistent decline of blood flow of more than 10% during the recovery periods. Conclusion Our data confirm previous results indicating that optic nerve head blood flow is autoregulated during an increase in perfusion pressure. In addition, we observed a subgroup of 6 subjects (15%) that showed an abnormal response, which is in keeping with our previous data. The mechanisms underlying this abnormal response remain to be shown. PMID:24324774

Boltz, Agnes; Told, Reinhard; Napora, Katarzyna J.; Palkovits, Stefan; Werkmeister, René M.; Schmidl, Doreen; Popa-Cherecheanu, Alina; Garhöfer, Gerhard; Schmetterer, Leopold

2013-01-01

285

Pulmonary artery pressure and cardiac function in children and adolescents after rapid ascent to 3,450 m.  

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High-altitude destinations are visited by increasing numbers of children and adolescents. High-altitude hypoxia triggers pulmonary hypertension that in turn may have adverse effects on cardiac function and may induce life-threatening high-altitude pulmonary edema (HAPE), but there are limited data in this young population. We, therefore, assessed in 118 nonacclimatized healthy children and adolescents (mean ± SD; age: 11 ± 2 yr) the effects of rapid ascent to high altitude on pulmonary artery pressure and right and left ventricular function by echocardiography. Pulmonary artery pressure was estimated by measuring the systolic right ventricular to right atrial pressure gradient. The echocardiography was performed at low altitude and 40 h after rapid ascent to 3,450 m. Pulmonary artery pressure was more than twofold higher at high than at low altitude (35 ± 11 vs. 16 ± 3 mmHg; P young population after rapid ascent to this altitude at which major tourist destinations are located. PMID:22523248

Allemann, Yves; Stuber, Thomas; de Marchi, Stefano F; Rexhaj, Emrush; Sartori, Claudio; Scherrer, Urs; Rimoldi, Stefano F

2012-06-15

286

Effects of small doses of ouabain on the arterial blood pressure of anesthetized hypertensive and normotensive rats  

OpenAIRE

Ouabain increases vascular resistance and may induce hypertension by inhibiting the Na+ pump. The effects of 0.18 and 18 µg/kg, and 1.8 mg/kg ouabain pretreatment on the phenylephrine (PHE; 0.1, 0.25 and 0.5 µg, in bolus)-evoked pressor responses were investigated using anesthetized normotensive (control and uninephrectomized) and hypertensive (1K1C and DOCA-salt treated) rats. Treatment with 18 µg/kg ouabain increased systolic and diastolic blood pressure in all groups studied. However, t...

Rossoni L.V.; Pinto V.D.; Vassallo D.V.

2001-01-01

287

Pressão arterial entre trabalhadores de curtume Blood pressure among tannery workers  

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Full Text Available INTRODUÇÃO: O grupo das doenças cardiovasculares tem sido apontado como a principal causa de óbito no Brasil desde os anos 70, sendo a hipertensão arterial sistêmica (HAS o fator de risco mais importante para esse grupo. Entre os trabalhadores observa-se correlação negativa entre o status ocupacional e a pressão arterial. Tais fatos ressaltam a importância do conhecimento da distribuição da pressão arterial sistêmica entre os distintos grupos profissionais. Assim, foi realizado estudo para descrever o status pressórico de uma população homogênea e estável de trabalhadores do setor secundário da economia, pouco especializados e que ganham baixos salários, estabelecendo a prevalência da HAS nesse grupo específico, relacionando-a com algumas covariáveis biológicas e socioeconômicas, e comparando-a com a prevalência de HAS em outros grupos profissionais no Brasil. MÉTODO: Foram estudados 73 trabalhadores regularmente empregados em julho de 1993 em um curtume situado no Município de Botucatu, cidade de médio porte da região Centro-Oeste do Estado de São Paulo, os quais foram submetidos a exame antropométrico, aferição de pressão arterial, anamnese e exame clínico. Os resultados foram comparados com os obtidos em estudos semelhantes, controlando-se o confundimento da idade por intermédio de diferentes técnicas. RESULTADOS: A prevalência bruta da HAS encontrada foi de 56,1%, sendo 15,8% a prevalência de hipertensão sistólica isolada. Ambas se associaram ao etilismo e ao tabagismo na população estudada. DISCUSSÃO: A prevalência da hipertensão foi consideravelmente alta e significativamente maior do que a encontrada em outros grupos de trabalhadores estudados no Brasil. Tal achado ressalta a necessidade da continuidade da investigação, objetivando o isolamento dos fatores implicados na elevação pressórica do grupo estudado.INTRODUCTION: Cardiovascular diseases have been shown to be the leading cause of death in Brazil since the 1970s. High blood pressure has been the major risk factor among the above mentioned diseases. A negative correlation between occupational qualification and blood pressure has been observed among workers. The above mentioned facts bring out the importance of the knowledge of high blood pressure distribution among the different occupational groups. The aim of the present study was to describe the distribution of blood pressure in stable and homogeneous population of unskilled, low wage larning industrial workers. The Prevalence of high blood pressure was established for this specific group. This prevalence was also related to some biological and socio-economical covariates as compared with that among other occupational groups in Brazil. METHOD: The subjects were 73 active employees at a tannery in Botucatu, state of S.Paulo, Brazil, in July 1993. These subjects underwent blood pressure measurements, anamnesis and clinical examination. The results were compared with those of similar studies carried out in elsewhere Brazil. Age confounding was controlled by different techniques. RESULT: The crude prevalence of high blood pressure detected in this group of workers was of 56.1%, with 15.8% of isolated systolic hypertension. Alcohol abuse and smoking were associated with high blood pressure and isolated systolic hypertension in the population studied. DISCUSSION: Prevalence of hypertension in the group studied is significantly higher than that observed in other groups of workers studied in Brazil. Such a finding points to the need for further investigation so as to isolate those factors involved in the increased blood pressure found in this group.

Ricardo Cordeiro

1998-10-01

288

Application of Static Pressure Change in Estimation of Elastic Parameters of Rabbit’s Artery by Doppler Ultrasound  

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Full Text Available Backgrounds/Objectives : Noninvasive evaluation of elastic properties of vessel wall is hampered by the absence of methods to directly asse ss local elasticity. In order to invasively record the static pressure of carotid artery dur ing cardiac cycle in rabbit s and compare it with noninvasive technique, T–shaped tubes have been designed and constructed and calibrated. A noninvasive method to measure static pressure in arteries and finally estimate the elasticity of vessels is provided. Materials and Methods: In male white rabbits, we estimated the static pressure changes in carotid artery noninvasively by measuring blood flow velocities throughout cardiac cycle using Color Doppler Ultrasound. The blood flow ve locities were converted to static pressure changes by using energy conservation low. The st atic pressure changes of arterial wall were estimated. These parameters were compared wi th measured actual static pressure changes using a T-shaped tube, that was inserted into the carotid artery and the static pressure change was measured in the side br anch of the tube. The elastic parameters in both methods were calculated and compared by pa ired t-test statistical analysis. Results: Statistical analysis of static pressure c hanges and elastic parameters in both methods showed that there was no significant difference between the two methods. Conclusion: By applying this noninvasive approach, we can estimate elastic parameters in arteries of normal people and patients with, or at risk of developing atherosclerosis for determination of disease extent. We propose this noninvasive method as an accurate and safe way suitable for screening of large popula tions of young and symptom-free individuals.

N. Nikanjam

2005-06-01

289

Measuring Partial Pressure of Ammonia in Arterial or Venous Blood VS total Ammonia Levels in Hepatic Encephalopathy  

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Full Text Available AIM: To find out the correlation between clinical grade of hepaticencephalopathy and different serum ammonia levels, namely,serum arterial ammonia, serum venous ammonia, partial pressureof ammonia in arterial plasma and partial pressure of ammonia invenous plasma.METHODS: After informed consent from patients or their relatives,100 patients in hepatic encephalopathy due to advanced liver disease,were examined for their clinical grade of hepatic encephalopathywithin 24 hours of admission. Fasting arterial and venous bloodsamples were collected and sent to lab within 30 min. ection. BloodpH was measured in both samples for each patient. Ammonia levelswere measured directly by an enzymatic UV-Method. Partial pressurein a given sample was calculated by the recommended formula, usingtotal ammonia and blood pH of the respective sample.RESULTS: Maximum number of patients (53% in this study was inclinical grade I of hepatic encephalopathy, 30% were in grade II, and12% were in Grade III. Only 5% were in grade IV. While comparingmeans of serum arterial ammonia (0.26049, serum venous ammonia(0.264, partial pressure of ammonia in arterial blood (4.520 andpartial pressure of ammonia (4.357 in venous blood with clinicalgrades of hepatic encephalopathy, they increased with increasingclinical grade of hepatic encephalopathy with p-values of 0.001, 0.01,0.002, and 0.003 respectively. Partial pressure of ammonia in venousblood was most strongly associated with hepatic encephalopathy(p-value 0.001 followed by serum venous ammonia (p-value 0.002.CONCLUSIONS: Total arterial ammonia, total venous ammonia,partial pressure of arterial ammonia, and partial pressure of venousammonia, all are positively and significantly correlated withworsening clinical grades of hepatic encephalopathy. Partial pressureof ammonia in venous blood followed by that in serum venousammonia were most strongly associated with grade of hepaticencephalopathy.

Mohammad Asif Mehmood

2013-05-01

290

Path length entropy analysis of diastolic heart sounds.  

Science.gov (United States)

Early detection of coronary artery disease (CAD) using the acoustic approach, a noninvasive and cost-effective method, would greatly improve the outcome of CAD patients. To detect CAD, we analyze diastolic sounds for possible CAD murmurs. We observed diastolic sounds to exhibit 1/f structure and developed a new method, path length entropy (PLE) and a scaled version (SPLE), to characterize this structure to improve CAD detection. We compare SPLE results to Hurst exponent, Sample entropy and Multiscale entropy for distinguishing between normal and CAD patients. SPLE achieved a sensitivity-specificity of 80%-81%, the best of the tested methods. However, PLE and SPLE are not sufficient to prove nonlinearity, and evaluation using surrogate data suggests that our cardiovascular sound recordings do not contain significant nonlinear properties. PMID:23930808

Griffel, Benjamin; Zia, Mohammad K; Fridman, Vladamir; Saponieri, Cesare; Semmlow, John L

2013-09-01

291

Modificaciones en la presión arterial y el pulso por ketamina, con y sin succinilcolina / Changes in blood pressure and heart rate by ketamine with and without succinylcholine  

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish Introducción: La ketamina es utilizada como anestésico general, de inducción y como analgésico. Objetivos: Evaluar los cambios en la presión arterial sistólica (PAS), diastólica (PAD) y frecuencia del pulso (FP) producidos por la ketamina, y la influencia de la succinilcolina. Diseño: Comparativo y [...] de observación. Institución: Clínica Maison de Santé, Lima, Perú. Participantes: Pacientes que recibieron ketamina. Intervenciones: La ketamina fue empleada como anestésico general único y de inducción. Por cada modalidad, se consideró doce pacientes. Los doce primeros recibieron ketamina 2 mg/kg endovenosa, con medición de la PAS, PAD y FP antes y después de la anestesia. Los otros doce recibieron ketamina más succinilcolina, midiéndose los parámetros antes y después. Se comparó los cambios. Principales medidas de resultados: Variaciones en la PAS, PAD y FP. Resultados: En los primeros doce pacientes, la ketamina elevó la PAS 26 ± 3 mmHg, p Abstract in english Introduction: Ketamine is used as a general anesthetic as well as for anesthesia induction and analgesia. Objectives: To assess modifications in systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) caused by ketamine, and if there is any influence of succinylcholine. De [...] sign: Comparative and observational study. Setting: Maison de Santé Clinic, Lima, Peru. Participants: Patients receiving ketamine. Interventions: Ketamine was used as a single drug for general anesthesia and for induction. Twelve patients were considered for each modality. The twelve first patients received ketamine, 2 mg/kg IV, and SBP, DBP and HR were measured before and after administering the drug. The second group received ketamine plus succinylcholine, and same parameters were measured. Main outcome measures: SBP, DBP, and HR variations. Results: Following ketamine injection in the first twelve patients there were elevations in SBP 26 ± 3 mmHg, p

Andrés, Callegari M; Pedro P., Álvarez-Falconí; Edmundo, Céspedes.

2011-04-01

292

Efeito da fadiga induzida pelo treino de força na resposta da pressão arterial em sujeitos hipertensos: Uma revisão sistemática / Effect of fatigue induced by strength training on blood pressure response in hypertensive subjects: A systematic review  

Scientific Electronic Library Online (English)

Full Text Available O objetivo do estudo foi proceder a uma revisão sistemática da literatura sobre a resposta da pressão arterial após o treino de força em hipertensos, procurando identificar o efeito da fadiga nessa resposta. Foi realizada uma pesquisa bibliográfica nas bases de dados SciELO, LILACS e PubMed/MedLine. [...] Foram encontrados 9377 estudos e apenas seis atenderam aos critérios de inclusão estabelecidos e foram incluídos na revisão. Cinco estudos (83,3%) verificaram uma redução na pressão arterial sistólica ou diastólica. Relativamente à fadiga, 66,7% (n = 4) dos estudos relataram que realizaram séries até a fadiga, ao passo que 33,3% (n = 2) relataram que as séries eram interrompidas antes da fadiga. Dos quatro estudos que utilizaram protocolos até a fadiga, 75% (n = 3) observaram redução da pressão arterial, e os dois estudos que interromperam as séries antes da fadiga também evidenciaram redução. A magnitude da redução da pressão arterial foi similar entre os estudos que utilizaram os dois protocolos. Sendo assim, os resultados indicaram que a redução da pressão arterial após o treino de força em sujeitos hipertensos é independente da ocorrência de fadiga. Abstract in english The objective of this study was to systematically review the literature on blood pressure response after strength training in hypertensive subjects, trying to identify the effect of failure in this response. We performed a literature search in SciELO, LILACS, PubMed / MedLine databases. Out of 9377 [...] studies, only six met the inclusion criteria and were included in the review. Five studies (83.3%) reported a reduction in systolic or diastolic blood pressure. Regarding failure, 66.7% (n = 4) of the studies performed the sets until failure while 33.3% (n = 2) interrupted exercise before failure. Out of the four studies that used protocols until failure, 75% (n=3) observed a reduction in blood pressure, and the two studies who discontinued before the series also showed a reduction of failure. The magnitude of blood pressure reduction was similar among studies that employed both protocols. Thus, the results indicated that the reduction in blood pressure after strength training in subjects with hypertension is independent of the occurrence of failure.

A.J., Rodrigues-da-Silva; A.A., Lima; S.C., Rodrigues; C.C., Júnior; R.M., Ritti-Dias.

2013-01-01

293

Left and right ventricular diastolic function in hemodialysis patients  

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Full Text Available The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD and the correlation of this func-tion with the duration of HD. The study included 42 patients (22 females and 20 males with chro-nic renal failure (CRF, treated with HD, and 40 healthy subjects (24 females and 16 males with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects under-went detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the inter-ventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E, acceleration time of E wave (AT-E, tricuspid E and A waves (E tr and A tr and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD.

Rudhani Ibrahim

2010-01-01

294

Left and right ventricular diastolic function in hemodialysis patients  

International Nuclear Information System (INIS)

The aim of this prospective study was the assessment of left ventricular and right ventricular diastolic function in patients on hemodialysis (HD) and the correlation of this function with the duration of HD. The study included 42 patients (22 females and 20 males) with chronic renal failure (CRF), treated with HD, and 40 healthy subjects (24 females and 16 males) with no history of cardiovascular disease and with normal renal function, who constituted the control group. The groups were matched for age and sex. All study patients and control subjects unde went detailed history taking and physical examination. They also underwent electrocardiogram, echocardiography and biochemical and hematological blood analyses. Significant differences were noted between the two groups in the two-dimensional and M-mode echocardiography findings concerning aortic root dimension, transverse diameter of the left atrium, thickness of the inter-ventricular septum, thickness of the left ventricular posterior wall, left ventricular diastolic diameter, left ventricular systolic diameter, shortening fraction, ejection fraction as well as findings from the pulse Doppler study, including E wave, A wave, E/A ratio, deceleration time of E wave (DT-E), acceleration time of E wave (AT-E), tricuspid E and A waves (E tr and A tr ) and E tr /A tr , ratio. There were significant changes in HD patients without arterial hypertension as well in the control group subjects. Our study suggests that the left ubjects. Our study suggests that the left ventricular and left atrial dimensions as well as the left ventricular wall thickness are augmented in patients with CRF treated with HD compared with the control group. Additionally, the left and right ventricular diastolic function is also reduced in these patients. These differences were also noted in patients with CRF without arterial hypertension. Left ventricular diastolic dysfunction had no correlation with the duration of HD (Author).

295

In vitro model to study arterial wall dynamics through pressure-diameter relationship analysis  

Scientific Electronic Library Online (English)

Full Text Available SciELO Argentina | Language: English Abstract in english This work describes the biophysical basis of blood vessels' wall dynamics and reports a methodology developed in our laboratory to characterize mechanical vessels' wall properties and those of vascular prostheses. Our study includes in vitro measurements of arteries, veins and ePTFE conduits placed [...] in a circulating loop. Segments are allowed to equilibrate for a period of 15 minutes under a steady state of flow (150 ml/min) and a mean pressure of 93 mmHg, at a stretching rate of 110 beats/min. Data analysis consisted in obtaining pressure-diameter loop in order to calculate: Incremental elastic modulus, wall viscosity, Peterson modulus, pulse wave velocity, characteristic impedance, stiffness index, cross sectional compliance and distensibility. Incremental elastic modulus of ePTFE (48.56±0.82 10(7)dyn/cm²) was significantly higher than that of the veins (26.19±19.90 10(7)dyn/cm²) and that of the arteries (4.06±2.55 10(7)dyn/cm²). This is an important approach, since mechanical wall dynamics plays a major role in vascular disease.

D., Bia; R. L., Armentano; Y., Zócalo; W., Barmak; E., Migliaro; E. I., Cabrera Fischer.

2005-07-01

296

Effect of chlorethylclonidine on arterial blood pressure and heart rate in the conscious rat.  

Science.gov (United States)

The effect of chlorethylclonidine (CEC) on arterial blood pressure and heart rate (HR) has been evaluated in the conscious rat. CEC injection (25 mg/kg i.p.) caused a statistically significant decrease in mean arterial blood pressure (MAP) that was seen 24 hr after treatment. CEC also induced a decrease in HR that was maximal at 45 min but returned to pretreatment levels after 3 hr. CEC had no effect on the ability of isoproterenol to increase HR. CEC treatment had little effect on the pressor dose-response curve of either phenylephrine or BHT 920. When injected into the brain (25 mg/kg, lateral ventricle), CEC had no effect on MAP or HR. Yohimbine injected into the lateral ventricle had no effect on the response to i.p. CEC. Prazosin, used as a standard for comparison, caused a larger fall in MAP than CEC and this hypotension was associated with tachycardia and a marked shift (greater than 300-fold) in the phenylephrine pressor dose-response curve. A reactive analog of prazosin, SZL-49 [1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(2-bicyclo[2,2,2]octa- 2,5-diene-2-carbonyl)piperazine], had effects similar to prazosin on MAP and HR.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1356153

Piascik, M T; Sparks, M S; Pruitt, T A

1992-09-01

297

Optimal systolic and diastolic reconstruction windows for coronary CT angiography using 320-detector rows dynamic volume CT  

Energy Technology Data Exchange (ETDEWEB)

Aim: To investigate the optimal pattern of systolic and diastolic reconstruction windows for coronary computed tomography (CT) angiography using 320-detector rows dynamic volume CT (DVCT). Material and methods: A prospective analysis was performed on the data from 77 patients who were admitted between December 2008 and July 2009 for DVCT. The images were reconstructed in 10% steps throughout the 10-100% of R-R interval. Data sets for the three major coronary arteries [right coronary artery (RCA), left anterior descending artery (LAD), and left circumflex artery (LCX)] were evaluated by two independent readers. The quality of the images from each examined artery was graded from 1 (no motion artefacts) to 4 (severe motion artefacts over the entire vessel). The optimal systolic and diastolic reconstruction windows and the relationship between image quality and heart rate (HR) were analysed. The HR at which the optimal reconstruction window shifted from diastole to systole was predicted. Results: The average HR during imaging was 69.5 {+-} 12.8 beats/min (range 46-102 beats/min). HR was positively correlated with the proportion of systole (r = 0.78, p < 0.001). As HR increased, the optimal reconstruction windows shifted to later phases in both systole and diastole. Image quality for optimal systolic and diastolic reconstructions both deteriorated significantly with higher HRs (r = 0.38, p < 0.001; r = 0.82, p < 0.001). However, image quality in systolic reconstructions did not deteriorate as much as in diastolic reconstructions. The cut-off HRs at which optimal reconstruction intervals turned from diastole to systole was 90.8 beats/min. Conclusions: In patients with a low HR, the optimal coronary reconstruction window is in mid-late diastole. As the HR increases, systolic reconstruction often yields superior image quality compared with diastolic reconstruction.

Sun, G., E-mail: cjr.sungang@vip.163.com [Department of Medical Imaging, Jinan Military General Hospital, Jinan, Shandong Province (China); Li, M., E-mail: limin22000@yahoo.com.cn [Department of Medical Imaging, Jinan Military General Hospital, Jinan, Shandong Province (China); Li, L.; Li, G.-Y.; Zhang, H.; Peng, Z.-H. [Department of Medical Imaging, Jinan Military General Hospital, Jinan, Shandong Province (China)

2011-07-15

298

Estudio comparativo de la presión arterial invasiva frente a la presión arterial no invasiva: Valoración de la diferencia / Comparative study of invasive blood pressure versus non-invasive blood pressure  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish En la práctica clínica, la tensión arterial es un parámetro importante en la valoración hemodinámica del paciente crítico. Existen dos formas de medición: Presión Invasiva (PI) y Presión No Invasiva (PNI). Como objetivos nos planteamos comparar la diferencia entre ambas formas de medición, valorar l [...] as posibles diferencias por la localización arterial, edad y sexo, valorar la influencia de la ventilación mecánica, drogas inotrópicas y antecedentes personales en la diferencia de Presión arterial Invasiva (PI) respecto a la Presión arterial No Invasiva (PNI). Identificar su significación clínica y estimar la fiabilidad de la PNI. Hicimos un estudio descriptivo, longitudinal y comparativo de marzo a diciembre 2008. Se analizó sexo, edad y localización arterial (hemicuerpo y arteria). Incluimos pacientes con arteria con curva óptima y calibración en el momento de medición en decúbito supino. Se tomó la PNI en ambos brazos con 5 minutos de diferencia, registrando la PI al mismo tiempo. Análisis con el Spss 15.0. Se analizó la diferencia en 109 pacientes con diferencias estadísticamente significativas en algún parámetro analizado. Como conclusiones y discusión planteamos que las diferencias encontradas no son clínicamente significativas y por tanto la PI y la PNI son fiables en estado óptimo de calibración. Abstract in english In clinical practice, blood pressure is an important parameter in patient critic hemodynamic valuation. There are two ways of measuring: Invasive Pressure (IP) and Non Invasive Pressure (NIP). As objectives, we set ourselves the task of comparing the difference between both forms of measurement, ass [...] essing the possible differences by arterial location, age and sex, assessing the influence of mechanical ventilation, inotropic drugs and casework in invasive blood pressure difference (IP) and non invasive arterial pressure (NIP). We sought to identify its clinical significance and estimate the reliability of the NIP. We conducted a descriptive, longitudinal and comparative study between March and December 2008. Sex, age and arterial location (hemi-body and artery) were analyzed. We have included patients with artery with optimal curve and calibration at the time of measurement in decubitus. NIP was taken in both arms at an interval of five minutes, and IP was recorded at the same time. Analysis was with SPSS 15.0. The difference was analyzed in 109 patients with statistically significant differences in any scanned parameters. Under discussion and conclusions we propose that the differences found are not clinically significant and therefore the IP and the NIP are reliable in optimal calibration state.

J.A., Simarro Blasco; M.C., Noheda Blasco; M., Bascuñana Blasco; M., Noheda Recuenco; I., Tolmo Aranda; M.I., Romero Carralero.

2011-10-01

299

Control neural de la circulación periférica y de la presión arterial / Neural control of the peripheral circulation and blood pressure  

Scientific Electronic Library Online (English)

Full Text Available En el siglo XIX, Claude Bernard descubrió la acción del sistema nervioso sobre el control de la circulación periférica. A principios del siglo XX, Ewald Hering descubrió el barorreceptor arterial y estudió el control reflejo de la frecuencia cardiaca y de la tensión arterial. Cowley y Guyton demostr [...] aron que la denervación de los barorreceptores de la carótida y de la aorta produce cambios persistentes en la tensión arterial en el animal experimental. El sistema nervioso autónomo es el principal regulador neural de la circulación y de la tensión arterial a corto plazo y latido a latido y ejerce su función mediante diversos reflejos que regulan el tono vasomotor, la frecuencia cardiaca y el gasto cardiaco. Con los nuevos métodos no invasivos que miden la tensión arterial latido a latido como el Finapres y con los métodos de medición de la variabilidad espectral de la frecuencia cardiaca y la tensión arterial, es posible en la actualidad medir muchas de las variables que regulan la circulación periférica y la tensión arterial. En este trabajo se presenta una revisión del control neural de la tensión arterial y de la frecuencia cardiaca, una breve reseña histórica y datos obtenidos con la medición de la tensión arterial latido a latido de manera no invasiva utilizando el sistema conocido como Finapres. Abstract in english In the XIX century Claude Bernard discovered the action of the nervous system on the peripheral circulation. In the first half of the XX century Ewald Hering discovered the baro-receptor and the reflex control of the heart rate and blood pressure. Cowley and Guyton demonstrated that that sino-aortic [...] denervation induces persistent changes in the blood pressure in the dog. The autonomic nervous system is mainly responsible for the regulation of the circulation and blood pressure in the short term on a beat to beat basis. It controls the vasomotor tone, the heart rate and the cardiac output. With the advent of non invasive methods that measure the blood pressure on a beat to beat basis (Finapres) and with the methods of measurement of the variability of the blood pressure in the frequency domain (spectral analysis) we can currently measure many variables including heart rate, blood pressure, stroke volume, peripheral resistances and the baroreceptor sensitivity and make some inferences about their control mechanisms. These variables can be measured at rest in the supine position, standing up, during rhythmic breathing and during the Valsalva maneuver. In this article we present a review of the neural control of the blood pressure and heart rate.

Bruno, Estañol; Manuel, Porras-Betancourt; Gustavo, Sánchez-Torres; Raúl, Martínez-Memije; Oscar, Infante; Horacio, Sentíes-Madrid.

2009-12-01

300

Evidence that blood pressure remains under the control of arterial baroreceptors in renal hypertensive rats  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of the present study was to determine the range of the influence of the baroreflex on blood pressure in chronic renal hypertensive rats. Supramaximal electrical stimulation of the aortic depressor nerve and section of the baroreceptor nerves (sinoaortic denervation were used to obtain a global analysis of the baroreceptor-sympathetic reflex in normotensive control and in chronic (2 months 1-kidney, 1-clip hypertensive rats. The fall in blood pressure produced by electrical baroreceptor stimulation was greater in renal hypertensive rats than in normotensive controls (right nerve: -47 ± 8 vs -23 ± 4 mmHg; left nerve: -51 ± 7 vs -30 ± 4 mmHg; and both right and left nerves: -50 ± 8 vs -30 ± 4 mmHg; P < 0.05. Furthermore, the increase in blood pressure level produced by baroreceptor denervation in chronic renal hypertensive rats was similar to that observed in control animals 2-5 h (control: 163 ± 5 vs 121 ± 1 mmHg; 1K-1C: 203 ± 7 vs 170 ± 5 mmHg; P < 0.05 and 24 h (control: 149 ± 3 vs 121 ± 1 mmHg; 1K-1C: 198 ± 8 vs 170 ± 5 mmHg; P < 0.05 after sinoaortic denervation. Taken together, these data indicate that the central and peripheral components of the baroreflex are acting efficiently at higher arterial pressure in renal hypertensive rats when the aortic nerve is maximally stimulated or the activity is abolished.

A.S. Trindade Jr.

2009-10-01

301

Cerebral white matter blood flow and arterial blood pressure in preterm infants  

DEFF Research Database (Denmark)

Abstract It is generally assumed that one reason why white matter injury is common in preterm infants is the relatively poor vascular supply. Aim: To examine whether blood flow to the white matter is relatively more reduced at low blood pressure than is blood flow to the brain as a whole. Methods: Thirteen normoxic preterm infants had blood flow imaging on 16 occasions with single-photon emission computed tomography (SPECT) using 99Tc labelled hexa-methylpropylenamide oxime (HMPAO) as the tracer. Gestational age was 26-32 weeks. Transcutaneous carbon dioxide was between 4.7 and 8.5 kPa and mean arterial blood pressure between 22 and 55 mmHg. Results: There was no statistically significant direct relation between white matter blood flow percentage and any of the variables. Using non-linear regression, however, assuming a plateau over a certain blood pressure threshold and a positive slope below this threshold, the relation to white matter flow percentage was statistically significant (p = 0.02). The threshold was 29 mmHg (95% confidence limits 26-33). Conclusion: Our analysis supports the concept of periventricular white matter as selectively vulnerable to ischaemia during episodes of low blood pressure.

BØrch, Klaus; Lou, Hans C

2010-01-01

302

Loci influencing blood pressure identified using a cardiovascular gene-centric array  

OpenAIRE

Blood pressure (BP) is a heritable determinant of risk for cardiovascular disease (CVD). To investigate genetic associations with systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP) and pulse pressure (PP), we genotyped ?50 000 single-nucleotide polymorphisms (SNPs) that capture variation in ?2100 candidate genes for cardiovascular phenotypes in 61 619 individuals of European ancestry from cohort studies in the USA and Europe. We identified novel associations between rs347...

Ganesh, Sk; Tragante, V.; Guo, W.; Guo, Y.; Lanktree, Mb; Smith, En; Johnson, T.; Castillo, Ba; Barnard, J.; Baumert, J.; Chang, Yc; Elbers, Cc; Farrall, M.; Fischer, Me; Gaunt, Nf

2013-01-01

303

Heart Rate Variability and Blood Pressure during Dynamic and Static Exercise at Similar Heart Rate Levels  

OpenAIRE

Aim was to elucidate autonomic responses to dynamic and static (isometric) exercise of the lower limbs eliciting the same moderate heart rate (HR) response. Method: 23 males performed two kinds of voluntary exercise in a supine position at similar heart rates: static exercise (SE) of the lower limbs (static leg press) and dynamic exercise (DE) of the lower limbs (cycling). Subjective effort, systolic (SBP) and diastolic blood pressure (DBP), mean arterial pressure (MAP), rate pressure product...

Weippert, Matthias; Behrens, Kristin; Rieger, Annika; Stoll, Regina; Kreuzfeld, Steffi

2013-01-01

304

Relación entre el tamaño renal y el perfil de presión arterial en pacientes con poliquistosis renal autosómica dominante sin insuficiencia renal / Relationship between kidney size and blood pressure profile in patients with autosomal dominant polycystic kidney disease without renal failure  

Scientific Electronic Library Online (English)

Full Text Available SciELO Spain | Language: Spanish Abstract in spanish Antecedentes: El aumento del tamaño renal desempeña un papel importante en el desarrollo de la hipertensión arterial (HTA) en pacientes con poliquistosis renal autosómica dominante (PQRAD) con función renal normal. Material y métodos: Se han practicado a 37 pacientes con PQRAD, filtrado glomerular e [...] stimado (FGe) por MDRD >60 ml/min/1,73 m² y supuestamente normotensos, una monitorización de la presión arterial (MAPA) y una ecografía renovesical para investigar la posible relación entre el aumento del tamaño renal y un perfil patológico de presión arterial (PA) en estadios de prehipertensión. Resultados: 13 pacientes resultaron ser normotensos, 11 presentaron HTA enmascarada, 4 tuvieron HTA de bata blanca y 9, HTA verdadera. Se ha observado en los pacientes normotensos con patrón reductor de la PA una correlación positiva y estadísticamente significativa entre el tamaño renal y la variabilidad de la presión arterial diastólica (PAD). Conclusiones: La MAPA permite realizar un diagnóstico precoz de la HTA e identificar a pacientes con hipertensión enmascarada. Este trabajo sugiere que en pacientes normotensos con PQRAD existe una posible relación entre el tamaño renal y un perfil de PA con mayor riesgo cardiovascular. Abstract in english Background: Enlargement of renal size plays an important role in the development of hypertension in patients with autosomal dominant polycystic kidney disease (ADPKD) and normal renal function. Methods: A 24h blood pressure monitoring (ABPM) and a renal ecography have been performed in 37 patients w [...] ith ADPKD and estimated glomerular filtration rate >60 ml/min/1,73m² to study the relationship between renal size and an altered blood pressure profile in prehypertension stages. Results: 13 patients had normal blood pressure, 11 were diagnosed of masked hypertension, 4 had white coat hypertension and 9 had hypertension. We have found in the normotensive group with a dipper blood pressure profile a positive and statistically significant relationship between renal size and diastolic blood pressure variability. Conclusions: ABPM helps to make an early diagnosis of hypertension and to identify those patients with masked hypertension. This study suggests a relationship between renal size and a blood pressure profile linked to a major cardiovasular risk in normotensive patients with ADPKD.

L., Sans Atxer; A., Roca-Cusachs; R., Torra; F., Calero; P., Arias; J., Ballarin; P., Fernández-Llama.

305

Role of inflammation and the angiotensin type 2 receptor in the regulation of arterial pressure during pregnancy in mice.  

Science.gov (United States)

During normal pregnancy the renin-angiotensin system is activated, yet pregnant women are resistant to the pressor effects of angiotensin II. Our aim was to determine the role of the angiotensin type 2 receptor (AT2R) in the regulation of arterial pressure, natriuresis, and immune cell infiltration during pregnancy. Mean arterial pressure was measured via telemetry, and flow cytometry was used to enumerate immune cell infiltration in 14-week-old wild-type and AT2R knockout mice during gestation. In wild-type mice, mean arterial pressure decreased during gestation, reaching a nadir at gestational day 9 (-6±2 mm?Hg) and returned to near preconception levels during late gestation. In AT2R-deficient mice, the midgestational decrease in mean arterial pressure was absent. Furthermore, mean arterial pressure was significantly increased during late gestation compared with wild-type mice (?10 mm?Hg). As expected, circulating immune cell activation was suppressed during pregnancy. However, this response was absent in AT2R-deficient mice. While renal immune cell infiltration was similar between the genotypes, there was a significant T cell phenotypic switch toward a proinflammatory T-helper 1 phenotype in AT2R-deficient mice. These data indicate that the AT2R plays an important role in arterial pressure regulation and may modulate T cell activation and renal cytokine production during pregnancy. Therefore, deficits in AT2R expression may contribute to pregnancy-induced hypertension and thus represents a potential therapeutic target. PMID:24935937

Mirabito, Katrina M; Hilliard, Lucinda M; Wei, Zihui; Tikellis, Chris; Widdop, Robert E; Vinh, Antony; Denton, Kate M

2014-09-01

306

Continuous Non-Invasive Arterial Pressure Technique Improves Patient Monitoring during Interventional Endoscopy  

Directory of Open Access Journals (Sweden)

Full Text Available Introduction: Close monitoring of arterial blood pressure (BP is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP. Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP®, CN Systems, Graz may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy. Methods: 40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP® in addition to standard monitoring (NIBP, ECG and oxygen saturation. All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP® values were calculated for every interval between two NIBP measurements. Results: 2660 minutes of monitoring were recorded (mean 60.1±34.4 min/patient. All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9±70.3 mg. The mean arterial pressure for CNAP® was 102.4±21.2 mmHg and 106.8±24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP® showed a maximum increase of 30.8±21.7% and a maximum decrease of 22.4±28.3% (mean of all intervals. Discussion: Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP® improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.

Sylvia Siebig, Felix Rockmann, Karl Sabel, Ina Zuber-Jerger, Christine Dierkes, Tanja Brünnler, Christian E. Wrede

2009-01-01

307

Algunas consideraciones sobre la hipertensión arterial en la diabetes mellitus tipo 2 / Some considerations related to arterial high blood pressure in Type 2 diabetes mellitus  

Scientific Electronic Library Online (English)

Full Text Available Se realizó una revisión del tema relacionado con la hipertensión arterial en el paciente diabético tipo 2, con el objetivo de actualizar algunos elementos particulares en este grupo de pacientes. Se plantea que su prevalencia es considerablemente más alta que en la población no diabética, donde la h [...] iperinsulinemia y la disfunción endotelial cobran un papel protagónico en su etiopatogenia. La hipertensión arterial en estos pacientes clínicamente se manifiesta como un patrón non dipper, lo que incrementa la morbimortalidad por esta entidad. El tratamiento medicamentoso es habitualmente necesario, y se usan como drogas de primera línea los inhibidores de la enzima convertidora, los antagonistas de los receptores de angiotensina ll y los calcioantagonistas, aunque se pueden utilizar también los diuréticos tiacídicos a dosis bajas. Abstract in english Authors made a review of the topic related to arterial high blood pressure in the patient presenting with Type 2 diabetes mellitus to update some particular elements in this group of patients. We propose that its prevalence is higher than that present in non-diabetic population, where the hyperinsul [...] inism and the endothelial dysfunction have a leading role in its ethiopathogenesis. The arterial high blood pressure in these patients clinically is manifested as a non-dipper pattern increasing the morbidity and mortality. Drug therapy is commonly necessary and as first line-drugs are used the converting-enzyme inhibitors, the agiotensin-II receptors antagonists, and the antagonists-calcium, although the low-dose thiacidic diuretics.

Miguel Ángel, Yanes Quesada; Marelys, Yanes Quesada; Raúl, Calderín Bouza; Jeddú, Cruz Hernández; Joel, Brooks Durrutí.

2009-09-01

308

Algunas consideraciones sobre la hipertensión arterial en la diabetes mellitus tipo 2 Some considerations related to arterial high blood pressure in Type 2 diabetes mellitus  

Directory of Open Access Journals (Sweden)

Full Text Available Se realizó una revisión del tema relacionado con la hipertensión arterial en el paciente diabético tipo 2, con el objetivo de actualizar algunos elementos particulares en este grupo de pacientes. Se plantea que su prevalencia es considerablemente más alta que en la población no diabética, donde la hiperinsulinemia y la disfunción endotelial cobran un papel protagónico en su etiopatogenia. La hipertensión arterial en estos pacientes clínicamente se manifiesta como un patrón non dipper, lo que incrementa la morbimortalidad por esta entidad. El tratamiento medicamentoso es habitualmente necesario, y se usan como drogas de primera línea los inhibidores de la enzima convertidora, los antagonistas de los receptores de angiotensina ll y los calcioantagonistas, aunque se pueden utilizar también los diuréticos tiacídicos a dosis bajas.Authors made a review of the topic related to arterial high blood pressure in the patient presenting with Type 2 diabetes mellitus to update some particular elements in this group of patients. We propose that its prevalence is higher than that present in non-diabetic population, where the hyperinsulinism and the endothelial dysfunction have a leading role in its ethiopathogenesis. The arterial high blood pressure in these patients clinically is manifested as a non-dipper pattern increasing the morbidity and mortality. Drug therapy is commonly necessary and as first line-drugs are used the converting-enzyme inhibitors, the agiotensin-II receptors antagonists, and the antagonists-calcium, although the low-dose thiacidic diuretics.

Miguel Ángel Yanes Quesada

2009-09-01

309

Clinical significance of inter-arm pressure difference and ankle-brachial pressure index in patients with suspected coronary artery disease  

International Nuclear Information System (INIS)

Although measuring blood pressure at the bilateral brachia is common in medical practice, its clinical significance in patients with suspected coronary artery disease (CAD) has not been fully clarified. The method of this study was to define the significance of inter-arm systolic blood pressure difference in patients with suspected CAD, and to assess the relationship between inter-arm pressure difference and CAD, simultaneous brachial and ankle blood pressure measurements and stress myocardial single-photon emission computed tomography (SPECT) were performed in 386 consecutive patients with suspected CAD, excluding those with previous myocardial infarction or coronary revascularization. Subclavian artery stenosis, defined as ?15 mmHg inter-arm systolic blood pressure difference, was found in 27 patients (7%). Age (65±12 vs 65±11 years), male sex (21/27 vs 244/359), prevalence of hypertension (63% vs 56%), hypercholesterolemia (63% vs 62%), diabetes mellitus (33% vs 38%), cigarette smoking (44% vs 41%) and family history of CAD (15% vs 12%) were similar between patients with subclavian artery stenosis and those without. The incidence of decreased ankle-brachial pressure index (ABI) was higher (37% vs 12%, p=0.001), and percentage ischemic myocardium as assessed by SPECT was greater (9.0±8.5% vs 5.6±6.6%, p=0.05) in patients with subclavian artery stenosis than in those without. Furthermore, significant correlations were observed between inter-arm pressure differed between inter-arm pressure difference and percentage ischemic myocardium (r=0.13; p=0.01), and ABI (r=-0.26, p<0.0001). Among 386 patients, 283 underwent coronary angiography, and 63% of those who had inter-arm blood pressure difference had CAD. Furthermore, 83% of those CAD patients had multi-vessel CAD, which is regarded as a high-risk subset for subsequent cardiac events. Inter-arm pressure difference is often found in patients with suspected CAD, and is associated with significant CAD and peripheral artery disease. Thus, inter-arm pressure difference may be regarded as a simple marker for coronary and peripheral artery diseases. (author)

310

Persistence of Circadian Variation in Arterial Blood Pressure in ?1/?2-Adrenergic Receptor-Deficient Mice  

OpenAIRE

The ?-adrenergic pathway has been considered one important effector of circadian variation in arterial pressure. Experiments were performed in ?1/?2-adrenergic receptor-deficient mice (?1/?2ADR-/-) to assess whether this pathway is required for circadian variation in mean arterial pressure (MAP) and to determine the impact of its loss on the response to changes in dietary salt. Twenty-four hour recordings of MAP, heart rate (HR) and locomotor activity were made in conscious 16-17 week ol...

Kim, Soo Mi; Huang, Yuning; Qin, Yan; Mizel, Diane; Schnermann, Jurgen; Briggs, Josephine P.

2008-01-01

311

Effects of PDE type 5 inhibitors on Left Ventricular Diastolic Dysfunction in Resistant Hypertension.  

Science.gov (United States)

Resistant hypertension (RHTN) is a multifactorial disease characterized by blood pressure (BP) levels above goal (140/90 mmHg) in spite of the concurrent use of three or more antihypertensive drugs of different classes. Moreover, it is well known that RHTN subjects have high prevalence of left ventricular diastolic dysfunction (LVDD), which leads to increased risk of heart failure progression. This review gathers data from studies evaluating the effects of phosphodiesterase-5 (PDE-5) inhibitors (administration of acute sildenafil and short-term tadalafil) on diastolic function, biochemical and hemodynamic parameters in patients with RHTN. Acute study with sildenafil treatment found that inhibition of PDE-5 improved hemodynamic parameters and diastolic relaxation. In addition, short-term study with the use of tadalafil demonstrated improvement of LVDD, cGMP and BNP-32 levels, regardless of BP reduction. No endothelial function changes were observed in the studies. The findings of acute and short-term studies revealed potential therapeutic effects of IPDE-5 drugs on LVDD in RHTN patients.A Hipertensão arterial resistente (HAR) é uma doença multifatorial caracterizada por níveis pressóricos acima das metas (140/90 mmHg), a despeito de tratamento farmacológico otimizado de 3 ou mais fármacos anti-hipertensivos de diferentes classes. Pacientes diagnosticados como hipertensos resistentes apresentam alta prevalência de disfunção diastólica do ventrículo esquerdo (DDVE) que proporciona risco aumentado para insuficiência cardíaca. Esta revisão reúne dados de estudos prévios avaliando os efeitos dos inibidores de fosfodiesterase-5 (PDE-5) (administração aguda de sildenafil e de curto prazo de tadalafil) na função diastólica e nos parâmetros bioquímicos e hemodinâmicos em pacientes com HAR. O estudo agudo com sildenafil demonstrou que a inibição da PDE-5 melhorou os parâmetros hemodinâmicos e de relaxamento diastólico. Além disso, o estudo curto prazo com o uso de tadalafil revelou melhora da DDVE e dos níveis de GMPc e BNP-32, independente de redução de pressão arterial. A função endotelial não apresentou alteração com ambos os tratamentos. Os resultados dos estudos agudo e de curto prazo sugerem efeitos terapêuticos potenciais dos fármacos inibidores da PDE-5 na disfunção diastólica em pacientes com HAR. PMID:25352458

Faria, Ana Paula Cabral de; Modolo, Rodrigo; Moreno, Beatriz Vaz Domingues; Moreno, Heitor

2015-01-01

312

Prediction of Arterial Blood pH and Partial Pressure of Carbon dioxide from Venous Blood Samples in Patients Receiving Mechanical Ventilation  

OpenAIRE

Substitution of arterial with venous blood samples to estimate blood gas status is highly preferable due to practical and safety concerns. Numerous studies support the substitution of arterial by venous blood samples, reporting strong correlations between arterial and venous values. This study further investigated the predictive ability of venous blood samples for arterial Acid-Base Balance (pH) and pressure of carbon dioxide (pCO2). Participants were 51 post-brain surgery patients receiving ...

Tavakol, Kamran; Ghahramanpoori, Bahareh; Fararouei, Mohammad

2013-01-01

313

Effects of Magneto-Hydrodynamic and Hematocrit on Blood Flow in an artery with multiple mild stenosis  

Directory of Open Access Journals (Sweden)

Full Text Available Fluid flow analysis of blood flow through multi stenosis arteries in the presence of magnetic field is investigated. In this paper the effect of magnetic field and shape of stenosis on the flow rate, pressure gradient, wall shear stress and resistance parameter is studied. The blood flowing through the artery is considered to be Newtonian. This model is consistent with the principles of Ferro hydrodynamics and magneto hydrodynamics (MHD. The results indicate that rise in systolic pressure and fall in diastolic pressure are very harmful for weak heart.

Nidhi Verma

2009-01-01

314

Hemodynamics and function of resistance arteries in healthy persons and end stage renal disease patients  

DEFF Research Database (Denmark)

INTRODUCTION: Cardiovascular disease is the leading cause of death in patients with end stage renal disease (ESRD). The vasodilator mechanisms in small resistance arteries are in earlier studies shown to be reduced in patients with end stage renal disease. We studied whether endothelium dependent vasodilatation were diminished in ESRD patients and the interaction between the macro- and microcirculation. METHODS: Eleven patients with ESRD had prior to renal transplant or insertion of peritoneal dialysis catheter measured pulse wave velocity. During surgery, a subcutaneous fat biopsy was extracted. Resistance arteries were then dissected and mounted on a wire myograph for measurements of dilator response to increasing concentrations of acetylcholine after preconstriction with noradrenaline. Twelve healthy kidney donors served as controls. RESULTS: Systolic blood pressure was elevated in patients compared to the healthy controls; no difference in the concentration of asymmetric dimethyl arginine was seen. No significant difference in the endothelium dependent vasodilatation between patients and controls was found. Correlation of small artery properties showed an inverse relationship between diastolic blood pressure and nitric oxide dependent vasodilatation in controls. Pulse pressure was positively correlated to the total endothelial vasodilatation in patients. A negative association between S-phosphate and endothelial derived hyperpolarisation-like vasodilatation was seen in resistance arteries from controls. CONCLUSION: This study finds similar vasodilator properties in kidney patients and controls. However, correlations of pulse pressure and diastolic blood pressure with resistance artery function indicate compensating measures in the microcirculation during end stage renal disease.

Borg, Morten K; Ivarsen, Per

2014-01-01

315

Blood pressure measurement  

Science.gov (United States)

Diastolic blood pressure; Systolic blood pressure; Blood pressure reading; Measuring blood pressure ... or your health care provider will wrap the blood pressure cuff snugly around your upper arm. The ...

316

Changes in vascular properties, not ventricular properties, predominantly contribute to baroreflex regulation of arterial pressure.  

Science.gov (United States)

Baroreflex modulates both the ventricular and vascular properties and stabilizes arterial pressure (AP). However, how changes in those mechanical properties quantitatively impact the dynamic AP regulation remains unknown. We developed a framework of circulatory equilibrium, in which both venous return and cardiac output are expressed as functions of left ventricular (LV) end-systolic elastance (Ees), heart rate (HR), systemic vascular resistance (R), and stressed blood volume (V). We investigated the contribution of each mechanical property using the framework of circulatory equilibrium. In six anesthetized dogs, we vascularly isolated carotid sinuses and randomly changed carotid sinus pressure (CSP), while measuring the LV Ees, aortic flow, right and left atrial pressure, and AP for at least 60 min. We estimated transfer functions from CSP to Ees, HR, R, and V in each dog. We then predicted these parameters in response to changes in CSP from the transfer functions using a data set not used for identifying transfer functions and predicted changes in AP using the equilibrium framework. Predicted APs matched reasonably well with those measured (r2=0.85-0.96, Pfunctions from CSP to mechanical properties using our framework of circulatory equilibrium. Changes in the vascular properties, not the ventricular properties, predominantly determine baroreflex-induced AP regulation. PMID:25362137

Sakamoto, Takafumi; Kakino, Takamori; Sakamoto, Kazuo; Tobushi, Tomoyuki; Tanaka, Atsushi; Saku, Keita; Hosokawa, Kazuya; Onitsuka, Ken; Murayama, Yoshinori; Tsutsumi, Takaki; Ide, Tomomi; Sunagawa, Kenji

2015-01-01

317

Detection of postischemic regional left ventricular delayed outward wall motion or diastolic stunning after exercise-induced ischemia in patients with stable effort angina by using color kinesis.  

Science.gov (United States)

To determine whether postischemic diastolic stunning could be detected using color kinesis, we evaluated regional left ventricular (LV) diastolic wall motion in 36 patients with stable effort angina and a coronary stenosis (> or = 70% of luminal diameter), and in 30 control subjects. Regional LV filling fraction in the short-axis view during the first 30% of the LV filling time (color kinesis diastolic index) was determined before, 20 minutes, 1 hour, and 24 hours after the treadmill exercise test. In 33 of the 36 patients (92%), new regional LV delayed outward motion during early diastole (color kinesis diastolic index exercise. The regional LV delayed diastolic wall motion showed significant improvement but persisted 1 hour afterward in 20 of 36 patients (56%), and disappeared 24 hours after exercise. Detection of regional stunned myocardium with impaired diastolic function may be a useful tool for the diagnosis of coronary artery disease. PMID:18187301

Ishii, Katsuhisa; Miwa, Kunihisa; Sakurai, Takahiro; Kataoka, Kazuaki; Imai, Makoto; Kintaka, Aya; Aoyama, Takeshi; Kawanami, Masaki

2008-04-01

318

Arterial pressure and cerebral blood flow variability: friend or foe? A review  

Directory of Open Access Journals (Sweden)

Full Text Available Variability in arterial pressure and cerebral blood flow has traditionally been interpreted as a marker of cardiovascular decompensation, and has been associated with negative clinical outcomes across varying time scales, from impending orthostatic syncope to an increased risk of stroke. Emerging evidence, however, suggests that increased hemodynamic variability may, in fact, be protective in the face of acute challenges to perfusion, including significant central hypovolemia and hypotension (including hemorrhage, and during cardiac bypass surgery. This review presents the dichotomous views on the role of hemodynamic variability on clinical outcome, including the physiological mechanisms underlying these patterns, and the potential impact of increased and decreased variability on cerebral perfusion and oxygenation. We suggest that reconciliation of these two apparently discrepant views may lie in the time scale of hemodynamic variability; short time scale variability appears to be cerebroprotective, while mid to longer term fluctuations are associated with primary and secondary end-organ dysfunction.

CarolineAliceRickards

2014-04-01

319

Effects of Weather and Heliophysical Conditions on Emergency Ambulance Calls for Elevated Arterial Blood Pressure  

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Full Text Available We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009–2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs, in which the conditions for the emergency calls were made coded I.10–I.15. The Kaunas Weather Station provided daily records of air temperature (T, wind speed (WS, relative humidity, and barometric pressure (BP. We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s increased the daily number of elevated arterial blood pressure (EABP by 12% (RR = 1.12; 95% confidence interval (CI 1.04–1.21; and WS ? 3.5 knots during days of T < 1.5 °C and T ? 12.5 °C by 8% (RR = 1.08; CI 1.04–1.12. An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ? 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population’s sensitivity to different weather conditions.

Jone Vencloviene

2015-02-01

320

Effects of weather and heliophysical conditions on emergency ambulance calls for elevated arterial blood pressure.  

Science.gov (United States)

We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009-2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs), in which the conditions for the emergency calls were made coded I.10-I.15. The Kaunas Weather Station provided daily records of air temperature (T), wind speed (WS), relative humidity, and barometric pressure (BP). We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s) increased the daily number of elevated arterial blood pressure (EABP) by 12% (RR = 1.12; 95% confidence interval (CI) 1.04-1.21); and WS ? 3.5 knots during days of T < 1.5 °C and T ? 12.5 °C by 8% (RR = 1.08; CI 1.04-1.12). An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ? 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population's sensitivity to different weather conditions. PMID:25734792

Vencloviene, Jone; Babarskiene, Ruta M; Dobozinskas, Paulius; Sakalyte, Gintare; Lopatiene, Kristina; Mikelionis, Nerijus

2015-01-01

321

Reflex control of arterial pressure and heart rate in short-term streptozotocin diabetic rats  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Impaired baroreflex sensitivity in diabetes is well described and has been attributed to autonomic diabetic neuropathy. In the present study conducted on acute (10-20 days) streptozotocin (STZ)-induced diabetic rats we examined: 1) cardiac baroreflex sensitivity, assessed by the slope of the linear [...] regression between phenylephrine- or sodium nitroprusside-induced changes in arterial pressure and reflex changes in heart rate (HR) in conscious rats; 2) aortic baroreceptor function by means of the relationship between systolic arterial pressure and aortic depressor nerve (ADN) activity, in anesthetized rats, and 3) bradycardia produced by electrical stimulation of the vagus nerve or by the iv injection of methacholine in anesthetized animals. Reflex bradycardia (-1.4 ± 0.1 vs -1.7 ± 0.1 bpm/mmHg) and tachycardia (-2.1 ± 0.3 vs -3.0 ± 0.2 bpm/mmHg) were reduced in the diabetic group. The gain of the ADN activity relationship was similar in control (1.7 ± 0.1% max/mmHg) and diabetic (1.5 ± 0.1% max/mmHg) animals. The HR response to vagal nerve stimulation with 16, 32 and 64 Hz was 13, 16 and 14% higher, respectively, than the response of STZ-treated rats. The HR response to increasing doses of methacholine was also higher in the diabetic group compared to control animals. Our results confirm the baroreflex dysfunction detected in previous studies on short-term diabetic rats. Moreover, the normal baroreceptor function and the altered HR responses to vagal stimulation or methacholine injection suggest that the efferent limb of the baroreflex is mainly responsible for baroreflex dysfunction in this model of diabetes.

322

Neuronostatin acts in brain to biphasically increase mean arterial pressure through sympatho-activation followed by vasopressin secretion: the role of melanocortin receptors  

OpenAIRE

Neuronostatin is a recently described neuropeptide that is derived from the somatostatin preprohormone. We have shown previously that neuronostatin led to a biphasic, dose-related increase in mean arterial pressure when injected into the lateral cerebroventricle of adult, male rats. Because neuronostatin depolarized both magnocellular and parvocellular, paraventricular nucleus neurons in hypothalamic slice preparations, we hypothesized that neuronostatin elevated mean arterial pressure first ...

Yosten, Gina L. C.; Pate, Alicia T.; Samson, Willis K.

2011-01-01

323

Increasing abdominal pressure with and without PEEP: effects on intra-peritoneal, intra-organ and intra-vascular pressures  

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Full Text Available Abstract Background Intra-organ and intra-vascular pressures can be used to estimate intra-abdominal pressure. The aim of this prospective, interventional study was to assess the effect of PEEP on the accuracy of pressure estimation at different measurement sites in a model of increased abdominal pressure. Methods Catheters for pressure measurement were inserted into the stomach, urinary bladder, peritoneal cavity, pulmonary artery and inferior vena cava of 12 pigs. The pressures were recorded simultaneously at baseline, during 10 cm H20 PEEP, external abdominal pressure (7 kg weight plus PEEP, external abdominal pressure without PEEP, and again under baseline conditions. Results (mean ± SD PEEP alone increased diastolic pulmonary artery and inferior vena cava pressure but had no effect on the other pressures. PEEP and external abdominal pressure increased intraperitoneal pressure from 6 ± 1 mm Hg to 9 ± 2 mm Hg, urinary bladder pressure from 6 ± 2 mm Hg to 11 ± 2 mm Hg (p = 0.012, intragastric pressure from 6 ± 2 mm Hg to 11 ± 2 mm Hg (all p ? 0.001, and inferior vena cava pressure from 11 ± 4 mm Hg to 15 ± 4 mm Hg (p = 0.01. Removing PEEP and maintaining extraabdominal pressure was associated with a decrease in pulmonary artery diastolic but not in any of the other pressures. There was a significant correlation among all pressures. Bias (-1 mm Hg and limits of agreement (3 to -5 mm Hg were similar for the comparisons of absolute intraperitoneal pressure with intra-gastric and urinary bladder pressure, but larger for the comparison between intraperitoneal and inferior vena cava pressure (-5, 0 to -11 mm Hg. Bias (0 to -1 mm Hg and limits of agreement (3 to -4 mm Hg for pressure changes were similar for all comparisons Conclusions Our data suggest that pressure changes induced by external abdominal pressure were not modified by changing PEEP between 0 and 10 cm H20.

Pradl Richard

2010-07-01

324

Diastolic Heart Failure: A Concise Review  

OpenAIRE

The concept of “diastolic” heart failure grew out of the observation that many patients who have the symptoms and signs of heart failure had an apparently normal left ventricular (LV) ejection fraction. Thus it was assumed that since systolic function was “preserved” the problem must lie in diastole, although it is not clear by whom or when this assumption was made. Never...

Aziz, Fahad; Tk, Luqman-arafath; Enweluzo, Chijioke; Dutta, Simanta; Zaeem, Misbah

2013-01-01

325

ORANGE JUICE AND BLOOD PRESSURE  

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Full Text Available

Blood pressure is the force of blood against artery walls. It is measured in millimeters of mercury (mm Hg and recorded as two numbers: systolic pressure (as the heart contracts over diastolic pressure (as the heart relaxes between beats. High blood pressure (hypertension is defined as chronically elevated high blood pressure, with systolic blood pressure (SBP of 140 mm Hg or greater, and diastolic blood pressure (DBP of 90 mm Hg or greater. High blood pressure (HBP, smoking, abnormal blood lipid levels, obesity and diabetes are risk factors for coronary heart disease, the leading cause of death in the US. Lifestyle modifications such as engaging in regular physical activity, quitting smoking and eating a healthy diet (limiting intake of saturated fat and sodium and increasing consumption of fiber, fruits and vegetables are advocated for the prevention, treatment, and control of HBP. As multiple factors influence blood pressure, the effects of each factor are typically modest, particularly in normotensive subjects, yet the combined effects can be substantial. Nutrition plays an important role in influencing blood pressure. Orange juice should be included as part of any low sodium diet and/or any blood pressure reducing eating plan, as it is sodium free, fat-free and can help meet recommended levels of potassium intake that may contribute to lower BP.

M. F. VALIM

2009-01-01

326

Immediate impact of exercise on arterial stiffness in humans  

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Full Text Available Background and objectives: Increased arterial stiffness is an accepted cardiovascular risk factor. Several studies have shown that regular exercise is associated with reduced arterial stiffness. However, the acute effect is not well known. The aim of this study was to evaluate the immediate impact of exercise on arterial stiffness measured by pulse wave velocity (PWV. Subjects and Methods: Data from 100 consecutive patients who underwent graded maximal aerobic exercise test and pulse wave velocity study due to chest pain were analyzed. Results: With respect to brachial-ankle pulse wave velocity (baPWV, it decreased after the exercise test (before vs. after; 1420 ± 260 vs. 1358 ± 245, 1428 ± 255, vs. 1360 ±239 cm/sec; left and right, respectively. Upper extremity systolic blood pressure did not change from baseline. However, upper extremity diastolic blood pressure increased slightly. In addition, lower extremity blood pressure decreased in both systolic and diastolic phases. In both normotensives and hypertensives, baPWV decreased after exercise test. Conclusion: Exercise immediately decreases arterial stiffness. 

Jae-Bin Seo

2013-01-01

327

Neural set point for the control of arterial pressure: role of the nucleus tractus solitarius  

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Full Text Available Abstract Background Physiological experiments have shown that the mean arterial blood pressure (MAP can not be regulated after chemo and cardiopulmonary receptor denervation. Neuro-physiological information suggests that the nucleus tractus solitarius (NTS is the only structure that receives information from its rostral neural nuclei and from the cardiovascular receptors and projects to nuclei that regulate the circulatory variables. Methods From a control theory perspective, to answer if the cardiovascular regulation has a set point, we should find out whether in the cardiovascular control there is something equivalent to a comparator evaluating the error signal (between the rostral projections to the NTS and the feedback inputs. The NTS would function as a comparator if: a its lesion suppresses cardiovascular regulation; b the negative feedback loop still responds normally to perturbations (such as mechanical or electrical after cutting the rostral afferent fibers to the NTS; c perturbation of rostral neural structures (RNS to the NTS modifies the set point without changing the dynamics of the elicited response; and d cardiovascular responses to perturbations on neural structures within the negative feedback loop compensate for much faster than perturbations on the NTS rostral structures. Results From the control theory framework, experimental evidence found currently in the literature plus experimental results from our group was put together showing that the above-mentioned conditions (to show that the NTS functions as a comparator are satisfied. Conclusions Physiological experiments suggest that long-term blood pressure is regulated by the nervous system. The NTS functions as a comparator (evaluating the error signal between its RNS and the cardiovascular receptor afferents and projects to nuclei that regulate the circulatory variables. The mean arterial pressure (MAP is regulated by the feedback of chemo and cardiopulmonary receptors and the baroreflex would stabilize the short term pressure value to the prevailing carotid MAP. The discharge rates of rostral neural projections to the NTS would function as the set point of the closed and open loops of cardiovascular control. No doubt, then, the RNS play a functional role not only under steady-state conditions, but also in different behaviors and pathologies.

Valentinuzzi Max E

2010-01-01

328

Evaluation of Blood Pressure Control using a New Arterial Stiffness Parameter, Cardio-ankle Vascular Index (CAVI)  

OpenAIRE

Arterial stiffness has been known to be a surrogate marker of arteriosclerosis, and also of vascular function. Pulse wave velocity (PWV) had been the most popular index and was known to be a predictor of cardiovascular events. But, it depends on blood pressure at measuring time. To overcome this problem, cardio-ankle vascular index (CAVI) is developed. CAVI is derived from stiffness parameter ? by Hayashi, and the equation of Bramwell-Hill, and is independent from blood pressure at a measuri...

Shirai, Kohji; Utino, Junji; Saiki, Atsuhito; Endo, Kei; Ohira, Masahiro; Nagayama, Daiji; Tatsuno, Ichiro; Shimizu, Kazuhiro; Takahashi, Mao; Takahara, Akira

2013-01-01

329

Outflow boundary conditions for 3D simulations of non-periodic blood flow and pressure fields in deformable arteries.  

OpenAIRE

The simulation of blood flow and pressure in arteries requires outflow boundary conditions that incorporate models of downstream domains. We previously described a coupled multidomain method to couple analytical models of the downstream domains with 3D numerical models of the upstream vasculature. This prior work either included pure resistance boundary conditions or impedance boundary conditions based on assumed periodicity of the solution. However, flow and pressure in art...

Vignon-clementel, Irene; Figueroa, C. A.; Jansen, K. E.; Taylor, C. A.

2010-01-01

330

Arterial wave reflection decreases gradually from supine to upright  

DEFF Research Database (Denmark)

BACKGROUND. An increase in total peripheral resistance (TPR) usually increases arterial wave reflection. During passive head-up tilt (HUT), however, arterial wave reflection decreases with increasing TPR. This study addressed whether arterial wave reflection gradually decreases during HUT. METHODS. In 10 healthy volunteers (22-39 years, nine males), we recorded finger arterial pressures in supine position (0°), and 30°and 70°degrees HUT and active standing (90°). Aortic pressure was constructed from the finger pressure signal and hemodynamics were calculated. Arterial wave reflection was quantified as the augmentation index (AIx) and the reflection magnitude (RM). RESULTS. During HUT, heart rate increased (p <0.001), stroke volume and cardiac output decreased (p <0.001 and p <0.01), diastolic blood pressure increased (p <0.001), whereas systolic blood pressure did not change. TPR increased from 0.9 dyn s/cm(5) at 0? to 1.2, 1.4 and 1.4 dyn s/cm(5) at 30°, 70° and 90° (p <0.001). AIx fell gradually from 25% at0°to 16%, -1% and -10% at 30°, 70° and 90° (p <0.001). The RM decreased from 0.572 at 0°to 0.456 at 90° (p <0.001). CONCLUSION. From supine to upright, arterial wave reflection represented as AIx and RM gradually decreases in the presence of increasing TPR.

van den Bogaard, Bas; Westerhof, Berend E

2011-01-01

331

Investigating complex patterns of blocked intestinal artery blood pressure signals by empirical mode decomposition and linguistic analysis  

International Nuclear Information System (INIS)

In this investigation, surgical operations of blocked intestinal artery have been conducted on pigs to simulate the condition of acute mesenteric arterial occlusion. The empirical mode