Winter metabolic depression does not change arterial baroreflex control of heart rate in the tegu lizard Salvator merianae.

Science.gov (United States)

Zena, Lucas A; Dantonio, Valter; Gargaglioni, Luciane H; Andrade, Denis V; Abe, Augusto S; Bícego, Kênia C

2016-03-01

Baroreflex regulation of blood pressure is important for maintaining appropriate tissue perfusion. Although temperature affects heart rate (fH) reflex regulation in some reptiles and toads, no data are available on the influence of temperature-independent metabolic states on baroreflex. The South American tegu lizard Salvator merianae exhibits a clear seasonal cycle of activity decreasing fH along with winter metabolic downregulation, independent of body temperature. Through pharmacological interventions (phenylephrine and sodium nitroprusside), the baroreflex control of fH was studied at ∼ 25 °C in spring-summer- and winter-acclimated tegus. In winter lizards, resting and minimum fH were lower than in spring-summer animals (respectively, 13.3 ± 0.82 versus 10.3 ± 0.81 and 11.2 ± 0.65 versus 7.97 ± 0.88 beats min(-1)), while no acclimation differences occurred in resting blood pressure (5.14 ± 0.38 versus 5.06 ± 0.56 kPa), baroreflex gain (94.3 ± 10.7 versus 138.7 ± 30.3% kPa(-1)) or rate-pressure product (an index of myocardial activity). Vagal tone exceeded the sympathetic tone of fH, especially in the winter group. Therefore, despite the lower fH, winter acclimation does not diminish the fH baroreflex responses or rate-pressure product, possibly because of increased stroke volume that may arise because of heart hypertrophy. Independent of acclimation, fH responded more to hypotension than to hypertension. This should imply that tegus, which have no pressure separation within the single heart ventricle, must have other protection mechanisms against pulmonary hypertension or oedema, presumably through lymphatic drainage and/or vagal vasoconstriction of pulmonary artery. Such a predominant fH reflex response to hypotension, previously observed in anurans, crocodilians and mammals, may be a common feature of tetrapods. © 2016. Published by The Company of Biologists Ltd.

Baroreflex failure: a neglected type of secondary hypertension

NARCIS (Netherlands)

Timmers, H. J. L. M.; Wieling, W.; Karemaker, J. M.; Lenders, J. W. M.

2004-01-01

The arterial baroreflex buffers abrupt transients of blood pressure and prevents pressure from rising or falling excessively. In experimental animals, baroreceptor denervation results in temporary or permanent increases in blood pressure level and variability, depending on the extent of denervation.

Baroreflex failure: a neglected type of secondary hypertension.

NARCIS (Netherlands)

Timmers, H.J.L.M.; Wieling, W.; Karemaker, J.M.; Lenders, J.W.M.

2004-01-01

The arterial baroreflex buffers abrupt transients of blood pressure and prevents pressure from rising or falling excessively. In experimental animals, baroreceptor denervation results in temporary or permanent increases in blood pressure level and variability, depending on the extent of denervation.

Baroreflex buffering in sedentary and endurance exercise-trained healthy men.

Science.gov (United States)

Christou, Demetra D; Jones, Pamela Parker; Seals, Douglas R

2003-06-01

Baroreflex buffering plays an important role in arterial blood pressure control. Previous reports suggest that baroreflex sensitivity may be altered in endurance exercise-trained compared with untrained subjects. It is unknown, however, if in vivo baroreflex buffering is altered in the endurance exercise-trained state in humans. Baroreflex buffering was determined in 36 healthy normotensive men (18 endurance exercise-trained, 41+/-5 [SEM] years; 18 untrained, 41+/-4 years) by measuring the potentiation of the systolic blood pressure responses to a phenylephrine bolus and to incremental phenylephrine infusion during compared with before ganglionic blockade with trimethaphan. The exercise-trained men had a lower resting heart rate and higher maximal oxygen consumption and heart rate variability than the sedentary control subjects (all P=0.01). Mean levels and variability of blood pressure, cardiovagal baroreflex sensitivity (change in heart rate/change in systolic blood pressure), and basal muscle sympathetic nerve activity were not different in the two groups. The systolic blood pressure responses to phenylephrine were not different in the endurance-trained and untrained men before or during ganglionic blockade (P>0.6). Measures of baroreflex buffering with the use of a phenylephrine bolus (3.9+/-0.8 versus 4.0+/-0.7, trained versus untrained, P=0.85) and incremental infusion (2.8+/-0.4 versus 2.5+/-0.6, P=0.67) were similar in the two groups. Baroreflex buffering does not differ in endurance exercise-trained compared with untrained healthy men. These results support the concept that habitual vigorous endurance exercise does not modulate in vivo baroreflex buffering in healthy humans.

A single inhalation exposure to acrolein desensitizes baroreflex responsiveness in Wistar-Kyoto and Spontaneously Hypertensive rats.

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Arterial baroreflex is one of the body's homeostatic mechanisms that regulate blood pressure (BP) by changing heart rate (HR) and vasoconstriction. Increases in BP reflexively cause HR to decrease, whereas decreases in BP depress the baroreflex and cause HR to rise. As such, baro...

A method for assessment of the dynamic response of the arterial baroreflex

DEFF Research Database (Denmark)

Lund, Morten T; Salomonsson, Max; Jonassen, Thomas E N

2018-01-01

AIM: The baroreflex is a key mechanism in cardiovascular regulation and alterations in baroreceptor function are seen in many diseases, including heart failure, obesity and hypertension. We propose a new method for analyzing baroreceptor function from continuous blood pressure and heart rate...... in both health and disease. METHODS: 48-hour data series of blood pressure and heart rate were collected with telemetry. Sprague-Dawley rats on standard chow (n=11) served as controls, while rats on a high-fat, high-fructose diet (n=6) constituted the obese-hypertensive model. A third group of rats...

Baroreflex and neurovascular responses to skeletal muscle mechanoreflex activation in humans: an exercise in integrative physiology.

Science.gov (United States)

Drew, Rachel C

2017-12-01

Cardiovascular adjustments to exercise resulting in increased blood pressure (BP) and heart rate (HR) occur in response to activation of several neural mechanisms: the exercise pressor reflex, central command, and the arterial baroreflex. Neural inputs from these feedback and feedforward mechanisms integrate in the cardiovascular control centers in the brain stem and modulate sympathetic and parasympathetic neural outflow, resulting in the increased BP and HR observed during exercise. Another specific consequence of the central neural integration of these inputs during exercise is increased sympathetic neural outflow directed to the kidneys, causing renal vasoconstriction, a key reflex mechanism involved in blood flow redistribution during increased skeletal muscle work. Studies in humans have shown that muscle mechanoreflex activation inhibits cardiac vagal outflow, decreasing the sensitivity of baroreflex control of HR. Metabolite sensitization of muscle mechanoreceptors can lead to reduced sensitivity of baroreflex control of HR, with thromboxane being one of the metabolites involved, via greater inhibition of cardiac vagal outflow without affecting baroreflex control of BP or baroreflex resetting. Muscle mechanoreflex activation appears to play a predominant role in causing renal vasoconstriction, both in isolation and in the presence of local metabolites. Limited investigations in older adults and patients with cardiovascular-related disease have provided some insight into how the influence of muscle mechanoreflex activation on baroreflex function and renal vasoconstriction is altered in these populations. However, future research is warranted to better elucidate the specific effect of muscle mechanoreflex activation on baroreflex and neurovascular responses with aging and cardiovascular-related disease. Copyright © 2017 the American Physiological Society.

Targeted deletion of neurokinin-1 receptor expressing nucleus tractus solitarii neurons precludes somatosensory depression of arterial baroreceptor-heart rate reflex.

Science.gov (United States)

Potts, J T; Fong, A Y; Anguelov, P I; Lee, S; McGovern, D; Grias, I

2007-03-30

Neurokinin-1 receptor (NK1-R) expressing neurons are densely distributed throughout the nucleus tractus solitarii (NTS). However, their fundamental role in arterial baroreflex function remains debated. Previously, our group has shown that activation of contraction-sensitive somatic afferents evoke substance P (SP) release in the NTS and resets the arterial baroreflex via activation of a GABAergic NTS circuit. Based on these findings, we hypothesized that modulation of arterial baroreflex function by somatic afferents is mediated by NK1-R dependent inhibition of barosensitive NTS circuits. In the present study, SP-conjugated saporin toxin (SP-SAP) was used to ablate NK1-R expressing NTS neurons. Contraction-sensitive somatic afferents were activated by electrically-evoked muscle contraction and the arterial baroreceptor-heart rate reflex was assessed by constructing reflex curves using a decerebrate, arterially-perfused preparation. Baseline baroreflex sensitivity was significantly attenuated in SP-SAP-treated rats compared with control rats receiving either unconjugated SAP or vehicle. Muscle contraction significantly attenuated baroslope in SAP and vehicle-treated animals and shifted the baroreflex curves to higher systemic pressure. In contrast, somatic afferent stimulation failed to alter baroslope or shift the baroreflex curves in SP-SAP-treated animals. Moreover, when reflex sensitivity was partially restored in SP-SAP animals, somatic stimulation failed to attenuate baroreflex bradycardia. In contrast, SP-SAP and somatic stimulation failed to blunt the reflex bradycardia evoked by the peripheral chemoreflex. Immunohistochemistry revealed that pretreatment with SP-SAP significantly reduced the number of NK1-R expressing neurons in the caudal NTS, while sparing NK1-R expressing neurons rostral to the injection site. This was accompanied by a significant reduction in the number of glutamic acid decarboxylase (GAD67) expressing neurons at equivalent levels of the

Impaired baroreflex function in mice overexpressing alpha-synuclein

Directory of Open Access Journals (Sweden)

Sheila eFleming

2013-07-01

Full Text Available Cardiovascular autonomic dysfunction, such as orthostatic hypotension consequent to baroreflex failure and cardiac sympathetic denervation, is frequently observed in the synucleinopathy Parkinson’s disease (PD. In the present study, the baroreceptor reflex was assessed in mice overexpressing human wildtype alpha-synuclein (Thy1-aSyn, a genetic mouse model of synucleinopathy. The beat-to-beat change in heart rate, computed from R-R interval, in relation to blood pressure was measured in anesthetized and conscious mice equipped with arterial blood pressure telemetry transducers during transient bouts of hypertension and hypotension. Compared to wildtype, tachycardia following nitroprusside-induced hypotension was significantly reduced in Thy1-aSyn mice. Thy1-aSyn mice also showed an abnormal cardiovascular response (i.e., diminished tachycardia to muscarinic blockade with atropine. We conclude that Thy1-aSyn mice have impaired basal and dynamic range of sympathetic and parasympathetic-mediated changes in heart rate and will be a useful model for long-term study of cardiovascular autonomic dysfunction associated with PD.

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans

OpenAIRE

Silvani, Alessandro; Calandra-Buonaura, Giovanna; Johnson, Blair D.; van Helmond, Noud; Barletta, Giorgio; Cecere, Anna G.; Joyner, Michael J.; Cortelli, Pietro

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological mechanisms that mediate the coupling between HP and SAP in response to different postures, we analyzed the cross-correlation functions between low-frequency HP and SAP fluctuations and estimated cBR...

Changes in plasma volume and baroreflex function following resistance exercise

Science.gov (United States)

Ploutz, L. L.; Tatro, D. L.; Dudley, G. A.; Convertino, V. A.

1993-01-01

The dynamics of change in plasma volume (PV) and baroreflex responses have been reported over 24 h immediately following maximal cycle exercise. The purpose of this study was to determine if PV and baroreflex showed similar changes for 24 h after resistance exercise. Eight men were studied on 2 test days, 1 week apart. On 1 day, per cent change (% delta) in PV was estimated at 0,3, and 6 h after resistance exercise using haematocrit and haemoglobin. Baseline PV was measured 24 h after exercise using Evans blue dye. The carotid baroreceptor-cardiac reflex response was measured before, and 3, 6, 9, 12, and 24 h post-exercise. Each subject performed six sets of the bench press and leg press with 10 repetitions per set with a load that induced failure within each set. On a control day, the protocol was used without exercise. Plasma volume did not change during the control day. There was a 20% decrease in PV immediately post-exercise; the recovery of the PV was rapid and complete within 3 h. PV was 20% greater 24 h post-exercise than on the control day. There were no differences in any of the baroreflex measurements. Therefore, it is suggested that PV shifts may occur without altering baroreflex sensitivity.

Baroreflex Sensitivity And Autonomic Nervous System Function In Carotid Sinus Hypersensitivity

DEFF Research Database (Denmark)

Brinth, Louise Schouborg; Pors, Kirsten; Theibel, Ann Cathrine

2015-01-01

hypersensitivity ranging from reduced to increased sensitivity compared to controls. We wanted to establish whether measures of baroreflex sensitivity and autonomic function differed between patients diagnosed with carotid sinus hypersensitivity and age matched controls. We included 36 patients (12 women; 74 +/-10...... sensitivity may not follow the same neuronal pathways as those responding to the crude external pressures applied during carotid sinus massage...

Time-dependent effects of training on cardiovascular control in spontaneously hypertensive rats: role for brain oxidative stress and inflammation and baroreflex sensitivity.

Directory of Open Access Journals (Sweden)

Gustavo S Masson

Full Text Available Baroreflex dysfunction, oxidative stress and inflammation, important hallmarks of hypertension, are attenuated by exercise training. In this study, we investigated the relationships and time-course changes of cardiovascular parameters, pro-inflammatory cytokines and pro-oxidant profiles within the hypothalamic paraventricular nucleus of the spontaneously hypertensive rats (SHR. Basal values and variability of arterial pressure and heart rate and baroreflex sensitivity were measured in trained (T, low-intensity treadmill training and sedentary (S SHR at weeks 0, 1, 2, 4 and 8. Paraventricular nucleus was used to determine reactive oxygen species (dihydroethidium oxidation products, HPLC, NADPH oxidase subunits and pro-inflammatory cytokines expression (Real time PCR, p38 MAPK and ERK1/2 expression (Western blotting, NF-κB content (electrophoretic mobility shift assay and cytokines immunofluorescence. SHR-S vs. WKY-S (Wistar Kyoto rats as time control showed increased mean arterial pressure (172±3 mmHg, pressure variability and heart rate (358±7 b/min, decreased baroreflex sensitivity and heart rate variability, increased p47phox and reactive oxygen species production, elevated NF-κB activity and increased TNF-α and IL-6 expression within the paraventricular nucleus of hypothalamus. Two weeks of training reversed all hypothalamic changes, reduced ERK1/2 phosphorylation and normalized baroreflex sensitivity (4.04±0.31 vs. 2.31±0.19 b/min/mmHg in SHR-S. These responses were followed by increased vagal component of heart rate variability (1.9-fold and resting bradycardia (-13% at the 4th week, and, by reduced vasomotor component of pressure variability (-28% and decreased mean arterial pressure (-7% only at the 8th week of training. Our findings indicate that independent of the high pressure levels in SHR, training promptly restores baroreflex function by disrupting the positive feedback between high oxidative stress and increased pro

Baroreflex sensitivity during rest and executive functioning in attention-deficit/hyperactivity disorder. The TRAILS study

NARCIS (Netherlands)

Dietrich, A.; Althaus, M.; Hartman, C.A.; Buitelaar, J.K.; Minderaa, R.B.; van den Hoofdakker, B.J.; Hoekstra, P.J.

Children with attention-deficit/hyperactivity disorder (ADHD) often show executive function (EF) problems and neurophysiological hypoarousal. Baroreceptor activation, as part of the baroreflex short-term blood pressure regulatory mechanism, has been linked to cortical inhibition and attenuated

Baroreflex sensitivity during rest and executive functioning in attention-deficit/hyperactivity disorder. The TRAILS study.

NARCIS (Netherlands)

Dietrich, A.; Althaus, M.; Hartman, C.A.; Buitelaar, J.K.; Mindera, R.B.; Hoofdakker, B.J. van den; Hoekstra, P.J.

2012-01-01

Children with attention-deficit/hyperactivity disorder (ADHD) often show executive function (EF) problems and neurophysiological hypoarousal. Baroreceptor activation, as part of the baroreflex short-term blood pressure regulatory mechanism, has been linked to cortical inhibition and attenuated

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans.

Science.gov (United States)

Silvani, Alessandro; Calandra-Buonaura, Giovanna; Johnson, Blair D; van Helmond, Noud; Barletta, Giorgio; Cecere, Anna G; Joyner, Michael J; Cortelli, Pietro

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological mechanisms that mediate the coupling between HP and SAP in response to different postures, we analyzed the cross-correlation functions between low-frequency HP and SAP fluctuations and estimated cBRS with the sequence technique in healthy male subjects during passive head-up tilt test (HUTT, n = 58), during supine wakefulness, supine slow-wave sleep (SWS), and in the seated and active standing positions ( n = 8), and during progressive loss of 1 L blood ( n = 8) to decrease central venous pressure in the supine position. HUTT, SWS, the seated, and the standing positions, but not blood loss, entailed significant increases in the positive correlation between HP and the previous SAP values, which is the expected result of arterial baroreflex control, compared with baseline recordings in the supine position during wakefulness. These increases were mirrored by increases in the low-frequency variability of SAP in each condition but SWS. cBRS decreased significantly during HUTT, in the seated and standing positions, and after blood loss compared with baseline during wakefulness. These decreases were mirrored by decreases in the RMSSD index, which reflects cardiac vagal modulation. These results support the view that the cBRS decrease associated with the upright posture is a byproduct of decreased cardiac vagal modulation, triggered by the arterial baroreflex in response to central hypovolemia. Conversely, the greater baroreflex contribution to cardiac control associated with upright posture may be explained, at least in part, by enhanced fluctuations of SAP, which elicit a more effective entrainment of HP fluctuations by the arterial baroreflex. These SAP fluctuations may result

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans

NARCIS (Netherlands)

Silvani, A.; Calandra-Buonaura, G.; Johnson, B.D.; Helmond, N. van; Barletta, G.; Cecere, A.G.; Joyner, M.J.; Cortelli, P.

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological

Protective effect of the daming capsule on impaired baroreflexes in STZ-induced diabetic rats with hyperlipoidemia

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Lu Guan-Yi

2010-12-01

Full Text Available Abstract Background The Daming capsule (DMC is a traditional Chinese medicine used to treat hyperlipoidemia. Both clinic trials and studies on animal models have demonstrated that DMC is beneficial against diabetic symptoms. Impairment of the baroreflex can cause life-threatening arrhythmias and sudden cardiac death in patients with diabetes mellitus (DM. This study was designed to elucidate the effects of DMC on baroreflexes in streptozocin (STZ-induced diabetic rats with hyperlipoidemia. Methods Wistar rats were randomly divided into three groups: untreated controls, rats pretreated STZ and high lipids (a diabetes model or DM rats, and DM rats treated with DMC. The baroreflex sensitivity was examined during intravenous injection of phenylephrine (PE or sodium nitroprusside (SNP and quantified by the change in heart rate over the change in mean arterial blood pressure (ΔHR/ΔMABP. Morphological remodeling of baroreceptors was analyzed by transmission electron microscopy (TEM. The mRNA levels and expression of GluR2 and a GABAA receptor subunit were measured by quantitative RT-PCR and Western blotting. Results Compared to untreated DM rats, DMC significantly elevated the ratio of ΔHR/ΔMABP by enhancing the compensatory reduction in HR (-ΔHR in response to PE-induced hypertension (+ΔMABP (P P P A receptor expression. Conclusion The Daming capsule partially reversed the parasympathetic baroreflex impairment observed in STZ-induced diabetic rats with hyperlipoidemia. Treatment with DMC also prevented the degeneration of neurons and myelinated axons in the brain stem NAm and reversed the down-regulation of GluR2 mRNA. Rescue of NAm function may contribute to the medicinal properties of DMC in diabetic rats.

Modeling baroreflex regulation of heart rate during orthostatic stress

DEFF Research Database (Denmark)

Olufsen, Mette; Tran, Hien T.; Ottesen, Johnny T.

2006-01-01

. The model uses blood pressure measured in the finger as an input to model heart rate dynamics in response to changes in baroreceptor nerve firing rate, sympathetic and parasympathetic responses, vestibulo-sympathetic reflex, and concentrations of norepinephrine and acetylcholine. We formulate an inverse...... in healthy and hypertensive elderly people the hysteresis loop shifts to higher blood pressure values and its area is diminished. Finally, for hypertensive elderly people the hysteresis loop is generally not closed indicating that during postural change from sitting to standing, the blood pressure resettles......During orthostatic stress, arterial and cardiopulmonary baroreflexes play a key role in maintaining arterial pressure by regulating heart rate. This study, presents a mathematical model that can predict the dynamics of heart rate regulation in response to postural change from sitting to standing...

Endogenous leptin contributes to baroreflex suppression within the solitary tract nucleus of aged rats

Science.gov (United States)

Arnold, Amy C.

2014-01-01

The decline in cardiovagal baroreflex function that occurs with aging is accompanied by an increase in circulating leptin levels. Our previous studies showed that exogenous leptin impairs the baroreflex sensitivity for control of heart rate in younger rats, but the contribution of this hormone to baroreflex dysfunction during aging is unknown. Thus we assessed the effect of bilateral leptin microinjection (500 fmol/60 nl) within the solitary tract nucleus (NTS) on the baroreflex sensitivity in older (66 ± 2 wk of age) urethane/chloralose anesthetized Sprague-Dawley rats with elevated circulating leptin levels. In contrast to the 63% reduction observed in younger rats, leptin did not alter the baroreflex sensitivity for bradycardia evoked by phenylephrine in older rats (0.76 ± 0.19 baseline vs. 0.71 ± 0.15 ms/mmHg after leptin; P = 0.806). We hypothesized that this loss of sensitivity reflected endogenous suppression of the baroreflex by elevated leptin, rather than cardiovascular resistance to the peptide. Indeed, NTS administration of a leptin receptor antagonist (75 pmol/120 nl) improved the baroreflex sensitivity for bradycardia in older rats (0.73 ± 0.13 baseline vs. 1.19 ± 0.26 at 10 min vs. 1.87 ± 0.32 at 60 min vs. 1.22 ± 0.54 ms/mmHg at 120 min; P = 0.002), with no effect in younger rats. There was no effect of the leptin antagonist on the baroreflex sensitivity for tachycardia, responses to cardiac vagal chemosensitive fiber activation, or resting hemodynamics in older rats. These findings suggest that the actions of endogenous leptin within the NTS, either produced locally or derived from the circulation, contribute to baroreflex suppression during aging. PMID:25260611

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

Science.gov (United States)

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

2013-01-01

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 interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the "Guyton-Coleman model", no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. representing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.

Spontaneous baroreflex sensitivity

DEFF Research Database (Denmark)

Barthel, Petra; Bauer, Axel; Müller, Alexander

2012-01-01

Low baroreflex sensitivity (BRS) indicates poor prognosis after acute myocardial infarction. Noninvasive BRS assessment is complicated by nonstationarities and noise in electrocardiogram and pressure signals. Phase-rectified signal averaging is a novel signal processing technology overcoming thes...

Estimated Aortic Stiffness is Independently Associated with Cardiac Baroreflex Sensitivity in Humans: Role of Aging and Habitual Endurance Exercise

Science.gov (United States)

Pierce, Gary L.; Harris, Stephen A.; Seals, Douglas R.; Casey, Darren P.; Barlow, Patrick B.; Stauss, Harald M.

2016-01-01

We hypothesized that differences in cardiac baroreflex sensitivity (BRS) would be independently associated with aortic stiffness and augmentation index (AI), clinical biomarkers of cardiovascular disease (CVD) risk, among young sedentary and middle-aged/older sedentary and endurance-trained adults. A total of 36 healthy middle-aged/older (age 55-76 years, n=22 sedentary; n=14 endurance-trained) and 5 young sedentary (age 18-31 years) adults were included in a cross-sectional study. A subset of the middle-aged/older sedentary adults (n=12) completed an 8-week aerobic exercise intervention. Invasive brachial artery blood pressure waveforms were used to compute spontaneous cardiac BRS (via sequence technique) and estimated aortic pulse wave velocity (PWV) and AI (AI, via brachial-aortic transfer function and wave separation analysis). In the cross-sectional study, cardiac BRS was 71% lower in older compared with young sedentary adults (Pendurance exercise (P=0.03). In a regression model that included age, sex, resting heart rate, mean arterial pressure (MAP), body mass index and maximal exercise oxygen uptake, estimated aortic PWV (β±SE = −5.76 ± 2.01, P=0.01) was the strongest predictor of BRS (Model R2=0.59, Pendurance exercise-related differences in cardiac BRS are independently associated with corresponding alterations in aortic PWV among healthy adults, consistent with a mechanistic link between variations in the sensitivity of the baroreflex and aortic stiffness with age and exercise. PMID:26911535

Estimated aortic stiffness is independently associated with cardiac baroreflex sensitivity in humans: role of ageing and habitual endurance exercise.

Science.gov (United States)

Pierce, G L; Harris, S A; Seals, D R; Casey, D P; Barlow, P B; Stauss, H M

2016-09-01

We hypothesised that differences in cardiac baroreflex sensitivity (BRS) would be independently associated with aortic stiffness and augmentation index (AI), clinical biomarkers of cardiovascular disease risk, among young sedentary and middle-aged/older sedentary and endurance-trained adults. A total of 36 healthy middle-aged/older (age 55-76 years, n=22 sedentary and n=14 endurance-trained) and 5 young sedentary (age 18-31 years) adults were included in a cross-sectional study. A subset of the middle-aged/older sedentary adults (n=12) completed an 8-week-aerobic exercise intervention. Invasive brachial artery blood pressure waveforms were used to compute spontaneous cardiac BRS (via sequence technique), estimated aortic pulse wave velocity (PWV) and AI (AI, via brachial-aortic transfer function and wave separation analysis). In the cross-sectional study, cardiac BRS was 71% lower in older compared with young sedentary adults (Pendurance exercise (P=0.03). In a regression model that included age, sex, resting heart rate, mean arterial pressure (MAP), body mass index and maximal exercise oxygen uptake, estimated aortic PWV (β±s.e.=-5.76±2.01, P=0.01) was the strongest predictor of BRS (model R(2)=0.59, Pendurance-exercise-related differences in cardiac BRS are independently associated with corresponding alterations in aortic PWV among healthy adults, consistent with a mechanistic link between variations in the sensitivity of the baroreflex and aortic stiffness with age and exercise.

Heart rate variability and baroreflex sensitivity in bilateral lung transplant recipients.

Science.gov (United States)

Fontolliet, Timothée; Gianella, Pietro; Pichot, Vincent; Barthélémy, Jean-Claude; Gasche-Soccal, Paola; Ferretti, Guido; Lador, Frédéric

2018-01-09

The effects of lung afferents denervation on cardiovascular regulation can be assessed on bilateral lung transplantation patients. The high-frequency component of heart rate variability is known to be synchronous with breathing frequency. Then, if heart beat is neurally modulated by breathing frequency, we may expect disappearance of high frequency of heart rate variability in bilateral lung transplantation patients. On 11 patients and 11 matching healthy controls, we measured R-R interval (electrocardiography), blood pressure (Portapres ® ) and breathing frequency (ultrasonic device) in supine rest, during 10-min free breathing, 10-min cadenced breathing (0·25 Hz) and 5-min handgrip. We analysed heart rate variability and spontaneous variability of arterial blood pressure, by power spectral analysis, and baroreflex sensitivity, by the sequence method. Concerning heart rate variability, with respect to controls, transplant recipients had lower total power and lower low- and high-frequency power. The low-frequency/high-frequency ratio was higher. Concerning systolic, diastolic and mean arterial pressure variability, transplant recipients had lower total power (only for cadenced breathing), low frequency and low-frequency/high-frequency ratio during free and cadenced breathing. Baroreflex sensitivity was decreased. Denervated lungs induced strong heart rate variability reduction. The higher low-frequency/high-frequency ratio suggested that the total power drop was mostly due to high frequency. These results support the hypothesis that neural modulation from lung afferents contributes to the high frequency of heart rate variability. © 2018 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

[Baroreflexes originated in vertebral artery zones upon peripheral vein tonus, systemic arterial blood pressure, and external respiration].

Science.gov (United States)

Agadzhanian, N A; Kupriianov, S V

2008-06-01

The investigation was intended to study the role ofbaroreceptors ofhemodynamically isolated zone of vertebral arteries in regulation of peripheral veins tonus, arterial pressure and external respiration. Pressure decrease in this vascular reflexogenic zone led to reflex responses of increase in femoral vein tonus, elevation of blood pressure level and stimulation of external respiration. The opposite reflex responses of cardio-respiratory functional system to initial pressure activation of vertebral arteries baroreceptors are observed. Basing on generalization of our own findings and similar physiological and morphological researches of other authors, it is established that afferentation from the vertebral artery zone is a reflexogenic factor of somatic muscles' veins tonus regulation. These reflexes of capacity vessels tonic activity changes are part of cardio-respiratory responses of maintaining the tissue gaseous exchange.

Baroreflex dysfunction in sick newborns makes heart rate an unreliable surrogate for blood pressure changes.

Science.gov (United States)

Govindan, Rathinaswamy B; Al-Shargabi, Tareq; Massaro, An N; Metzler, Marina; Andescavage, Nickie N; Joshi, Radhika; Dave, Rhiya; du Plessis, Adre

2016-06-01

Cerebral pressure passivity (CPP) in sick newborns can be detected by evaluating coupling between mean arterial pressure (MAP) and cerebral blood flow measured by near infra-red spectroscopy hemoglobin difference (HbD). However, continuous MAP monitoring requires invasive catheterization with its inherent risks. We tested whether heart rate (HR) could serve as a reliable surrogate for MAP in the detection of CPP in sick newborns. Continuous measurements of MAP, HR, and HbD were made and partitioned into 10-min epochs. Spectral coherence (COH) was computed between MAP and HbD (COHMAP-HbD) to detect CPP, between HR and HbD (COHHR-HbD) for comparison, and between MAP and HR (COHMAP-HR) to quantify baroreflex function (BRF). The agreement between COHMAP-HbD and COHHR-HbD was assessed using ROC analysis. We found poor agreement between COHMAP-HbD and COHHR-HbD in left hemisphere (area under the ROC curve (AUC) 0.68) and right hemisphere (AUC 0.71). Baroreflex failure (COHMAP-HR not significant) was present in 79% of epochs. Confining comparison to epochs with intact BRF showed an AUC of 0.85 for both hemispheres. In these sick newborns, HR was an unreliable surrogate for MAP required for the detection of CPP. This is likely due to the prevalence of BRF failure in these infants.

Assessment of baroreflex sensitivity from spontaneous oscillations of blood pressure and heart rate: proven clinical value?

International Nuclear Information System (INIS)

Pinna, Gian Domenico; Maestri, Roberto; La Rovere, Maria Teresa

2015-01-01

The baroreceptor-heart rate reflex (baroreflex sensitivity, BRS) is a key mechanism contributing to the neural regulation of the cardiovascular system. Several methods have been proposed so far to assess BRS by analyzing the spontaneous beat-to-beat fluctuations of arterial blood pressure and heart rate. These methods are inherently simple, non-invasive and low-cost. This study is an attempt to address the question of whether spontaneous baroreflex methods have proven to be of value in the clinical setting. In the first part of this article, we critically review most representative clinical studies using spontaneous BRS techniques either for risk stratification or treatment evaluation, these being major issues in the clinical management of the patients. In the second part, we address two important aspects of spontaneous BRS measurements: measurability and reliability. Estimation of BRS in the studies selected for the review was performed according to the sequence, transfer function, alpha-index and phase-rectified signal averaging method. Arterial blood pressure was recorded non-invasively during supine, short-term (<30 min) laboratory recordings. The conclusion from this review is that spontaneous BRS techniques have been shown to be of great value in clinical practice but further work is needed to confirm the validity of previous findings and to widen the field of clinical applications. Measurability and reliability can be a major issue in the measurement of spontaneous BRS, particularly in some patient populations like post-myocardial infarction and heart failure patents. Main causes of poor measurability are: non-sinus rhythm, a high rate of ectopic beats and the need for recorded time series of RR interval and arterial blood pressure to satisfy the constraints of the different BRS estimation algorithms. As for reliability, within-subject variability is rather high in the measurements of spontaneous BRS and, therefore, should be carefully taken into account

Dynamic Aerobic Exercise Induces Baroreflex Improvement in Diabetic Rats

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Luciana Jorge

2012-01-01

Full Text Available The objective of the present study was to investigate the effects of an acute aerobic exercise on arterial pressure (AP, heart rate (HR, and baroreflex sensitivity (BRS in STZ-induced diabetic rats. Male Wistar rats were divided into control (n=8 and diabetic (n=8 groups. AP, HR, and BRS, which were measured by tachycardic and bradycardic (BR responses to AP changes, were evaluated at rest (R and postexercise session (PE on a treadmill. At rest, STZ diabetes induced AP and HR reductions, associated with BR impairment. Attenuation in resting diabetes-induced AP (R: 103±2 versus PE: 111±3 mmHg and HR (R: 290±7 versus PE: 328±10 bpm reductions and BR dysfunction (R: -0.70±0.06 versus PE: -1.21±0.09 bpm/mmHg was observed in the postexercise period. In conclusion, the hemodynamic and arterial baro-mediated control of circulation improvement in the postexercise period reinforces the role of exercise in the management of cardiovascular risk in diabetes.

Dynamic Aerobic Exercise Induces Baroreflex Improvement in Diabetic Rats

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Jorge, Luciana; da Pureza, Demilto Y.; Dias, Danielle da Silva; Conti, Filipe Fernandes; Irigoyen, Maria-Cláudia; De Angelis, Kátia

2012-01-01

The objective of the present study was to investigate the effects of an acute aerobic exercise on arterial pressure (AP), heart rate (HR), and baroreflex sensitivity (BRS) in STZ-induced diabetic rats. Male Wistar rats were divided into control (n = 8) and diabetic (n = 8) groups. AP, HR, and BRS, which were measured by tachycardic and bradycardic (BR) responses to AP changes, were evaluated at rest (R) and postexercise session (PE) on a treadmill. At rest, STZ diabetes induced AP and HR reductions, associated with BR impairment. Attenuation in resting diabetes-induced AP (R: 103 ± 2 versus PE: 111 ± 3 mmHg) and HR (R: 290 ± 7 versus PE: 328 ± 10 bpm) reductions and BR dysfunction (R: −0.70 ± 0.06 versus PE: −1.21 ± 0.09 bpm/mmHg) was observed in the postexercise period. In conclusion, the hemodynamic and arterial baro-mediated control of circulation improvement in the postexercise period reinforces the role of exercise in the management of cardiovascular risk in diabetes. PMID:22203833

Baroreflex Responses to Acute Changes in Blood Volume in Humans

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Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

1990-01-01

To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro-reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationship, of the cardio-pulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venous Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). The results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulmonary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

Four faces of baroreflex failure: hypertensive crisis, volatile hypertension, orthostatic tachycardia, and malignant vagotonia

Science.gov (United States)

Ketch, Terry; Biaggioni, Italo; Robertson, RoseMarie; Robertson, David

2002-01-01

BACKGROUND: The baroreflex normally serves to buffer blood pressure against excessive rise or fall. Baroreflex failure occurs when afferent baroreceptive nerves or their central connections become impaired. In baroreflex failure, there is loss of buffering ability, and wide excursions of pressure and heart rate occur. Such excursions may derive from endogenous factors such as stress or drowsiness, which result in quite high and quite low pressures, respectively. They may also derive from exogenous factors such as drugs or environmental influences. METHODS AND RESULTS: Impairment of the baroreflex may produce an unusually broad spectrum of clinical presentations; with acute baroreflex failure, a hypertensive crisis is the most common presentation. Over succeeding days to weeks, or in the absence of an acute event, volatile hypertension with periods of hypotension occurs and may continue for many years, usually with some attenuation of pressor surges and greater prominence of depressor valleys during long-term follow-up. With incomplete loss of baroreflex afferents, a mild syndrome of orthostatic tachycardia or orthostatic intolerance may appear. Finally, if the baroreflex failure occurs without concomitant destruction of the parasympathetic efferent vagal fibers, a resting state may lead to malignant vagotonia with severe bradycardia and hypotension and episodes of sinus arrest. CONCLUSIONS: Although baroreflex failure is not the most common cause of the above conditions, correct differentiation from other cardiovascular disorders is important, because therapy of baroreflex failure requires specific strategies, which may lead to successful control.

First-order differential-delay equation for the baroreflex predicts the 0.4-Hz blood pressure rhythm in rats.

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Burgess, D E; Hundley, J C; Li, S G; Randall, D C; Brown, D R

1997-12-01

We have described a 0.4-Hz rhythm in renal sympathetic nerve activity (SNA) that is tightly coupled to 0.4-Hz oscillations in blood pressure in the unanesthetized rat. In previous work, the relationship between SNA and fluctuations in mean arterial blood pressure (MAP) was described by a set of two first-order differential equations. We have now modified our earlier model to test the feasibility that the 0.4-Hz rhythm can be explained by the baroreflex without requiring a neural oscillator. In this baroreflex model, a linear feedback term replaces the sympathetic drive to the cardiovascular system. The time delay in the feedback loop is set equal to the time delay on the efferent side, approximately 0.5 s (as determined in the initial model), plus a time delay of 0.2 s on the afferent side for a total time delay of approximately 0.7 s. A stability analysis of this new model yields feedback resonant frequencies close to 0.4 Hz. Because of the time delay in the feedback loop, the proportional gain may not exceed a value on the order of 10 to maintain stability. The addition of a derivative feedback term increases the system's stability for a positive range of derivative gains. We conclude that the known physiological time delay for the sympathetic portion of the baroreflex can account for the observed 0.4-Hz rhythm in rat MAP and that the sensitivity of the baroreceptors to the rate of change in blood pressure, as well as average blood pressure, would enhance the natural stability of the baroreflex.

Induction of hypertension blunts baroreflex inhibition of vasopressin neurons in the rat.

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Han, Su Young; Bouwer, Gregory T; Seymour, Alexander J; Korpal, Aaron K; Schwenke, Daryl O; Brown, Colin H

2015-11-01

Vasopressin secretion from the posterior pituitary gland is determined by action potential discharge of hypothalamic magnocellular neurosecretory cells. Vasopressin is a potent vasoconstrictor, but vasopressin levels are paradoxically elevated in some patients with established hypertension. To determine whether vasopressin neurons are excited in hypertension, extracellular single-unit recordings of vasopressin neurons from urethane-anaesthetized Cyp1a1-Ren2 rats with inducible angiotensin-dependent hypertension were made. The basal firing rate of vasopressin neurons was higher in hypertensive Cyp1a1-Ren2 rats than in non-hypertensive Cyp1a1-Ren2 rats. The increase in firing rate was specific to vasopressin neurons because oxytocin neuron firing rate was unaffected by the induction of hypertension. Intravenous injection of the α1-adrenoreceptor agonist, phenylephrine (2.5 μg/kg), transiently increased mean arterial blood pressure to cause a baroreflex-induced inhibition of heart rate and vasopressin neuron firing rate (by 52 ± 9%) in non-hypertensive rats. By contrast, intravenous phenylephrine did not inhibit vasopressin neurons in hypertensive rats, despite a similar increase in mean arterial blood pressure and inhibition of heart rate. Circulating angiotensin II can excite vasopressin neurons via activation of afferent inputs from the subfornical organ. However, the increase in vasopressin neuron firing rate and the loss of inhibition by intravenous phenylephrine were not blocked by intra-subfornical organ infusion of the angiotensin AT1 receptor antagonist, losartan. It can be concluded that increased vasopressin neuron activity at the onset of hypertension is driven, at least in part, by reduced baroreflex inhibition of vasopressin neurons and that this might exacerbate the increase in blood pressure at the onset of hypertension. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Non-invasive baroreflex sensitivity assessment using wavelet transfer function-based time–frequency analysis

International Nuclear Information System (INIS)

Keissar, K; Gilad, O; Maestri, R; Pinna, G D; La Rovere, M T

2010-01-01

A novel approach for the estimation of baroreflex sensitivity (BRS) is introduced based on time–frequency analysis of the transfer function (TF). The TF method (TF-BRS) is a well-established non-invasive technique which assumes stationarity. This condition is difficult to meet, especially in cardiac patients. In this study, the classical TF was replaced with a wavelet transfer function (WTF) and the classical coherence was replaced with wavelet transform coherence (WTC), adding the time domain as an additional degree of freedom with dynamic error estimation. Error analysis and comparison between WTF-BRS and TF-BRS were performed using simulated signals with known transfer function and added noise. Similar comparisons were performed for ECG and blood pressure signals, in the supine position, of 19 normal subjects, 44 patients with a history of previous myocardial infarction (MI) and 45 patients with chronic heart failure. This yielded an excellent linear association (R > 0.94, p < 0.001) for time-averaged WTF-BRS, validating the new method as consistent with a known method. The additional advantage of dynamic analysis of coherence and TF estimates was illustrated in two physiological examples of supine rest and change of posture showing the evolution of BRS synchronized with its error estimations and sympathovagal balance

The estrogen-dependent baroreflex dysfunction caused by nicotine in female rats is mediated via NOS/HO inhibition: Role of sGC/PI3K/MAPK{sub ERK}

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Fouda, Mohamed A.; El-Gowelli, Hanan M.; El-Gowilly, Sahar M.; El-Mas, Mahmoud M., E-mail: mahelm@hotmail.com

2015-12-15

We have previously reported that estrogen (E2) exacerbates the depressant effect of chronic nicotine on arterial baroreceptor activity in female rats. Here, we tested the hypothesis that this nicotine effect is modulated by nitric oxide synthase (NOS) and/or heme oxygenase (HO) and their downstream soluble guanylate cyclase (sGC)/phosphatidylinositol 3-kinase (PI3K)/mitogen-activated protein kinases (MAPKs) signaling. We investigated the effects of (i) inhibition or facilitation of NOS or HO on the interaction of nicotine (2 mg/kg/day i.p., 2 weeks) with reflex bradycardic responses to phenylephrine in ovariectomized (OVX) rats treated with E2 or vehicle, and (ii) central pharmacologic inhibition of sGC, PI3K, or MAPKs on the interaction. The data showed that the attenuation by nicotine of reflex bradycardia in OVXE2 rats was abolished after treatment with hemin (HO inducer) or L-arginine (NOS substrate). The hemin or L-arginine effect disappeared after inhibition of NOS (Nω-Nitro-L-arginine methyl ester hydrochloride, L-NAME) and HO (zinc protoporphyrin IX, ZnPP), respectively, denoting the interaction between the two enzymatic pathways. E2-receptor blockade (ICI 182,780) reduced baroreflexes in OVXE2 rats but had no effect on baroreflex improvement induced by hemin or L-arginine. Moreover, baroreflex enhancement by hemin was eliminated following intracisternal (i.c.) administration of wortmannin, ODQ, or PD98059 (inhibitors of PI3K, sGC, and extracellular signal-regulated kinases, MAPK{sub ERK}, respectively). In contrast, the hemin effect was preserved after inhibition of MAPK{sub p38} (SB203580) or MAPK{sub JNK} (SP600125). Overall, NOS/HO interruption underlies baroreflex dysfunction caused by nicotine in female rats and the facilitation of NOS/HO-coupled sGC/PI3K/MAPK{sub ERK} signaling might rectify the nicotine effect. - Highlights: • Hemin or L-arginine blunts baroreflex dysfunction caused by nicotine in OVXE2 rats. • NO/CO crosstalk mediates

The degree of cardiac baroreflex involvement during active standing is associated with the quality of life in fibromyalgia patients.

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Antonio Roberto Zamunér

Full Text Available Fibromyalgia syndrome (FMS is a rheumatologic disorder characterized by chronic widespread pain, fatigue and other symptoms. Baroreflex dysfunction has been observed in women with FMS. However, it is unknown whether the limited involvement of the baroreflex control during an orthostatic stimulus has some impact on the quality of life of the FMS patient. Therefore, the aim of the study is evaluate the relationship between the quality of life of the FMS patient and indexes of the cardiovascular autonomic control as estimated from spontaneous fluctuations of heart period (HP and systolic arterial pressure (SAP. We enrolled 35 women with FMS (age: 48.8±8.9 years; body mass index: 29.3±4.3 Kg/m2. The electrocardiogram, non-invasive finger blood pressure and respiratory activity were continuously recorded during 15 minutes at rest in supine position (REST and in orthostatic position during active standing (STAND. Traditional cardiovascular autonomic control markers were assessed along with a Granger causality index assessing the strength of the causal relation from SAP to HP (CRSAP→HP and measuring the degree of involvement of the cardiac baroreflex. The impact of FMS on quality of life was quantified by the fibromyalgia impact questionnaire (FIQ and visual analog score for pain (VAS pain. No significant linear association was found between FIQ scores and the traditional cardiovascular indexes both at REST and during STAND (p>0.05. However, a negative relationship between CRSAP→HP during STAND and FIQ score was found (r = -0.56, p<0.01. Similar results were found with VAS pain. In conclusion, the lower the degree of cardiac baroreflex involvement during STAND in women with FMS, the higher the impact of FMS on the quality of life, thus suggesting that Granger causality analysis might be clinically helpful in assessing the state of the FMS patient.

A computational analysis of the long-term regulation of arterial pressure [v1; ref status: indexed, http://f1000r.es/1xq

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Daniel A. Beard

2013-10-01

Full Text Available 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 interacting neurohumoral mechanisms, result in chronic relationships between water and salt excretion and pressure that are much steeper than the acute relationships. While the view that renal function is the dominant controller of arterial pressure has been supported by computer models of the cardiovascular system known as the “Guyton-Coleman model”, no unambiguous description of a computer model capturing chronic adaptation of acute renal function in blood pressure control has been presented. Here, such a model is developed with the goals of: 1. capturing the relevant mechanisms in an identifiable mathematical model; 2. identifying model parameters using appropriate data; 3. validating model predictions in comparison to data; and 4. probing hypotheses regarding the long-term control of arterial pressure and the etiology of primary hypertension. The developed model reveals: long-term control of arterial blood pressure is primarily through the baroreflex arc and the renin-angiotensin system; and arterial stiffening provides a sufficient explanation for the etiology of primary hypertension associated with ageing. Furthermore, the model provides the first consistent explanation of the physiological response to chronic stimulation of the baroreflex.

Orthostatic blood pressure control before and after spaceflight, determined by time-domain baroreflex method

NARCIS (Netherlands)

Gisolf, J.; Immink, R. V.; van Lieshout, J. J.; Stok, W. J.; Karemaker, J. M.

2005-01-01

Reduction in plasma volume is a major contributor to orthostatic tachycardia and hypotension after spaceflight. We set out to determine time- and frequency-domain baroreflex (BRS) function during preflight baseline and venous occlusion and postflight orthostatic stress, testing the hypothesis that a

The benefits of soluble non-bacterial fraction of kefir on blood pressure and cardiac hypertrophy in hypertensive rats are mediated by an increase in baroreflex sensitivity and decrease in angiotensin-converting enzyme activity.

Science.gov (United States)

Brasil, Girlandia Alexandre; Silva-Cutini, Mirian de Almeida; Moraes, Flávia de Souza Andrade; Pereira, Thiago de Melo Costa; Vasquez, Elisardo Corral; Lenz, Dominik; Bissoli, Nazaré Souza; Endringer, Denise Coutinho; de Lima, Ewelyne Miranda; Biancardi, Vinícia Campana; Maia, June Ferreira; de Andrade, Tadeu Uggere

We aimed to evaluate whether long-term treatment with the soluble non-bacterial fraction of kefir affects mean arterial pressure (MAP) and cardiac hypertrophy through the modulation of baroreflex sensitivity, ACE activity, and the inflammatory-to-anti-inflammatory cytokine ratio in spontaneously hypertensive rats (SHRs). SHRs were treated with the soluble non-bacterial kefir fraction (SHR-kefir) or with kefir vehicle (SHR-soluble fraction of milk). Normotensive control Wistar Kyoto animals received the soluble fraction of milk. All treatments were administered by gavage (0.3 mL/100g/body weight), once daily for eight weeks. At the end, after basal MAP and Heart Rate (HT) measurement, barorreflex sensitivity was evaluated through in bolus administrations of sodium nitroprusside and phenylephrine (AP 50 [arterial pressure 50%], the lower plateau, and HR range were measured). ACE activity and cytokines (TNF-α and IL-10) were evaluated by ELISA. Cardiac hypertrophy was analysed morphometrically. Compared to SHR control, SHR-kefir exhibited a significant decrease in both MAP (SHR: 184 ± 5; SHR-Kefir: 142 ± 8 mmHg), and HR (SHR: 360 ± 10; SHR-kefir: 310 ± 14 bpm). The non-bacterial fraction of kefir also reduced cardiac hypertrophy, TNF-α-to-IL10 ratio, and ACE activity in SHRs. SHR-kefir baroreflex sensitivity, resulted in a partial but significant recovery of baroreflex gain, as demonstrated by improvements in AP 50 , the lower plateau, and HR range. In summary, our results indicate that long-term administration of the non-bacterial fraction of kefir promotes a significant decrease in both MAP and HR, by improving baroreflex, and reduces cardiac hypertrophy in SHRs, likely via ACE inhibition, and reduction of the TNF-α-to-IL10 ratio. Copyright © 2018 Elsevier Inc. All rights reserved.

The degree of cardiac baroreflex involvement during active standing is associated with the quality of life in fibromyalgia patients.

Science.gov (United States)

Zamunér, Antonio Roberto; Porta, Alberto; Andrade, Carolina Pieroni; Forti, Meire; Marchi, Andrea; Furlan, Raffaello; Barbic, Franca; Catai, Aparecida Maria; Silva, Ester

2017-01-01

Fibromyalgia syndrome (FMS) is a rheumatologic disorder characterized by chronic widespread pain, fatigue and other symptoms. Baroreflex dysfunction has been observed in women with FMS. However, it is unknown whether the limited involvement of the baroreflex control during an orthostatic stimulus has some impact on the quality of life of the FMS patient. Therefore, the aim of the study is evaluate the relationship between the quality of life of the FMS patient and indexes of the cardiovascular autonomic control as estimated from spontaneous fluctuations of heart period (HP) and systolic arterial pressure (SAP). We enrolled 35 women with FMS (age: 48.8±8.9 years; body mass index: 29.3±4.3 Kg/m2). The electrocardiogram, non-invasive finger blood pressure and respiratory activity were continuously recorded during 15 minutes at rest in supine position (REST) and in orthostatic position during active standing (STAND). Traditional cardiovascular autonomic control markers were assessed along with a Granger causality index assessing the strength of the causal relation from SAP to HP (CRSAP→HP) and measuring the degree of involvement of the cardiac baroreflex. The impact of FMS on quality of life was quantified by the fibromyalgia impact questionnaire (FIQ) and visual analog score for pain (VAS pain). No significant linear association was found between FIQ scores and the traditional cardiovascular indexes both at REST and during STAND (p>0.05). However, a negative relationship between CRSAP→HP during STAND and FIQ score was found (r = -0.56, pquality of life, thus suggesting that Granger causality analysis might be clinically helpful in assessing the state of the FMS patient.

The effects of baroreflex activation therapy on blood pressure and sympathetic function in patients with refractory hypertension

DEFF Research Database (Denmark)

Gordin, Daniel; Fadl Elmula, Fadl Elmula M; Andersson, Bert

2017-01-01

). Results: The primary end point is the reduction in 24-hour systolic ABPM by BAT at 8 months, as compared to pharmacotherapy. Secondary and tertiary endpoints are effects of BAT on home and office blood pressures, measures of indices of cardiac and vascular structure and function during follow......Objective: To explore the effects of baroreflex activation therapy (BAT) on hypertension in patients with treatment resistant or refractory hypertension. Methods: This investigator-initiated randomized, double-blind, 1:1 parallel-design clinical trial will include 100 patients with refractory...... hypertension from 6 tertiary referral hypertension centers in the Nordic countries. A Barostim Neo System will be implanted and after 1 month patients will be randomized to either BAT for 16 months or continuous pharmacotherapy (BAT off) for 8 months followed by BAT for 8 months. A second randomization...

Efeitos da exposição à fumaça lateral do cigarro sobre o barorreflexo em ratos adultos Efectos de la exposición al humo lateral del cigarrillo sobre el barorreflejo en ratones adultos Sidestream cigarette smoke exposure effects on baroreflex in adult rats

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Vitor E. Valenti

2011-02-01

�N: Nuestros datos sugieren que tres semanas de exposición a la HLC no son suficientes para causar daño significativo a los parámetros cardiovasculares y sensibilidad barorreflexa en ratones Wistar normotensos.BACKGROUND: It has been evidenced in the literature that exposure to cigarette smoke causes hypertension in rats; however, it has not been demonstrated if the baroreflex function is impaired before the animal becomes hypertensive. OBJECTIVE: We evaluated short-term effects of sidestream cigarette smoke (SSCS exposure on baroreflex function in Wistar normotensive rats. METHODS: Rats were exposed to SSCS during three weeks, 180 minutes, five days per week, at a concentration of monoxide carbon between 100-300 ppm. Mean arterial pressure (MAP and heart rate (HR were evaluated through cannulation of the femoral vein and artery. RESULTS: There was no significant difference between control and SSCS groups regarding basal mean arterial pressure and heart rate, sympathetic and parasympathetic components of the baroreflex function. CONCLUSION: Our data suggest that three weeks of exposure to SSCS is not enough to significantly impair cardiovascular parameters and baroreflex sensitivity in normotensive Wistar rats.

Antenatal hypoxia induces programming of reduced arterial blood pressure response in female rat offspring: role of ovarian function.

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DaLiao Xiao

Full Text Available In utero exposure to adverse environmental factors increases the risk of cardiovascular disease in adulthood. The present study tested the hypothesis that antenatal hypoxia causes a gender-dependent programming of altered arterial blood pressure response (BP in adult offspring. Time-dated pregnant rats were divided into normoxic and hypoxic (10.5% O2 from days 15 to 21 of gestation groups. The experiments were conducted in adult offspring. Antenatal hypoxia caused intrauterine growth restriction, and resulted in a gender-dependent increase Angiotensin II (Ang II-induced BP response in male offspring, but significant decrease in BP response in female offspring. The baroreflex sensitivity was not significantly altered. Consistent with the reduced blood pressure response, antenatal hypoxia significantly decreased Ang II-induced arterial vasoconstriction in female offspring. Ovariectomy had no significant effect in control animals, but significantly increased Ang II-induced maximal BP response in prenatally hypoxic animals and eliminated the difference of BP response between the two groups. Estrogen replacement in ovariectomized animals significantly decreased the BP response to angiotensin II I only in control, but not in hypoxic animals. The result suggests complex programming mechanisms of antenatal hypoxia in regulation of ovary function. Hypoxia-mediated ovary dysfunction results in the phenotype of reduced vascular contractility and BP response in female adult offspring.

Time course analysis of baroreflex sensitivity during postural stress

NARCIS (Netherlands)

Westerhof, Berend E.; Gisolf, Janneke; Karemaker, John M.; Wesseling, Karel H.; Secher, Niels H.; van Lieshout, Johannes J.

2006-01-01

Postural stress requires immediate autonomic nervous action to maintain blood pressure. We determined time-domain cardiac baroreflex sensitivity (BRS) and time delay (tau) between systolic blood pressure and interbeat interval variations during stepwise changes in the angle of vertical body axis

Arterial endothelial function measurement method and apparatus

Energy Technology Data Exchange (ETDEWEB)

Maltz, Jonathan S; Budinger, Thomas F

2014-03-04

A "relaxoscope" (100) detects the degree of arterial endothelial function. Impairment of arterial endothelial function is an early event in atherosclerosis and correlates with the major risk factors for cardiovascular disease. An artery (115), such as the brachial artery (BA) is measured for diameter before and after several minutes of either vasoconstriction or vasorelaxation. The change in arterial diameter is a measure of flow-mediated vasomodification (FMVM). The relaxoscope induces an artificial pulse (128) at a superficial radial artery (115) via a linear actuator (120). An ultrasonic Doppler stethoscope (130) detects this pulse 10-20 cm proximal to the point of pulse induction (125). The delay between pulse application and detection provides the pulse transit time (PTT). By measuring PTT before (160) and after arterial diameter change (170), FMVM may be measured based on the changes in PTT caused by changes in vessel caliber, smooth muscle tone and wall thickness.

Arterial function of carotid and brachial arteries in postmenopausal vegetarians

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Su T

2011-08-01

Full Text Available Ta-Chen Su1, Pao-Ling Torng2, Jiann-Shing Jeng3, Ming-Fong Chen1, Chiau-Suong Liau1,41Division of Cardiology, Department of Internal Medicine, 2Department of Obstetrics and Gynecology, 3Department of Neurology, National Taiwan University Hospital, National Taiwan University College of Medicine, 4Cardiovascular Center, Taipei Buddist Tzu-Chi Hospital, Hsin-Dian, Taipei, TaiwanBackground: Vegetarianism is associated with a lower risk of cardiovascular disease. However, studies of arterial function in vegetarians are limited.Methods: This study investigated arterial function in vegetarianism by comparing 49 healthy postmenopausal vegetarians with 41 age-matched omnivores. The arterial function of the common carotid artery was assessed by carotid duplex, while the pulse dynamics method was used to measure brachial artery distensibility (BAD, compliance (BAC, and resistance (BAR. Fasting blood levels of glucose, lipids, lipoprotein (a, high-sensitivity C-reactive protein, homocysteine, and vitamin B12 were also measured.Results: Vegetarians had significantly lower serum cholesterol, high-density and low-density lipoprotein, and glucose compared with omnivores. They also had lower vitamin B12 but higher homocysteine levels. Serum levels of lipoprotein (a and high-sensitivity C-reactive protein were no different between the two groups. There were no significant differences in carotid beta stiffness index, BAC, and BAD between the two groups even after adjustment for associated covariates. However, BAR was significantly lower in vegetarians than in omnivores. Multiple linear regression analysis revealed that age and pulse pressure were two important determinants of carotid beta stiffness index and BAD. Vegetarianism is not associated with better arterial elasticity.Conclusion: Apparently healthy postmenopausal vegetarians are not significantly better in terms of carotid beta stiffness index, BAC, and BAD, but have significantly decreased BAR than

Ovarian hormone deprivation reduces oxytocin expression in Paraventricular Nucleus preautonomic neurons and correlates with baroreflex impairment in rats

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Vitor Ulisses De Melo

2016-10-01

Full Text Available The prevalence of cardiovascular diseases including hypertension increases dramatically in women after menopause, however the mechanisms involved remain incompletely understood. Oxytocinergic (OTergic neurons are largely present within the paraventricular nucleus of the hypothalamus (PVN. Several studies have shown that OTergic drive from PVN to brainstem increases baroreflex sensitivity and improves autonomic control of the circulation. Since preautonomic PVN neurons express different types of estrogen receptors, we hypothesize that ovarian hormone deprivation causes baroreflex impairment, autonomic imbalance and hypertension by negatively impacting OTergic drive and oxytocin levels in pre-autonomic neurons. Here, we assessed oxytocin gene and protein expression (qPCR and immunohistochemistry within PVN subnuclei in sham-operated and ovariectomized Wistar rats. Conscious hemodynamic recordings were used to assess resting blood pressure and heart rate and the autonomic modulation of heart and vessels was estimated by power spectral analysis. We observed that the ovarian hormone deprivation in ovariectomized rats decreased baroreflex sensitivity, increased sympathetic and reduced vagal outflows to the heart and augmented the resting blood pressure. Of note, ovariectomized rats had reduced PVN oxytocin mRNA and protein expression in all pre-autonomic PVN subnuclei. Furthermore, reduced PVN oxytocin protein levels were positively correlated with decreased baroreflex sensitivity and negatively correlated with increased LF/HF ratio. These findings suggest that reduced oxytocin expression in OTergic neurons of the PVN contributes to the baroreflex dysfunction and autonomic dysregulation observed with ovarian hormone deprivation.

Strain differences in baroceptor reflex in adult Wistar Kyoto rats

Directory of Open Access Journals (Sweden)

Vitor E. Valenti

2010-01-01

Full Text Available OBJECTIVES: A subset of normotensive Sprague-Dawley rats show lower baroreflex sensitivity; however, no previous study investigated whether there are differences in baroreflex sensitivity within this subset. Our study compared baroreflex sensitivity among conscious rats of this specific subtype. METHODS: Male Wistar Kyoto (WKY rats (16 weeks old were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure (MAP and heart rate (HR. Baroreflex gain was calculated as the ratio between change in HR and MAP variation (ΔHR/ΔMAP in response to a depressor dose of sodium nitroprusside (SNP, 50 µg/kg, i.v. and a pressor dose of phenylephrine (PE, 8 µg/kg, i.v.. Rats were divided into four groups: 1 low bradycardic baroreflex (LB, baroreflex gain (BG between -1 and -2 bpm/mmHg tested with PE; 2 high bradycardic baroreflex (HB, BG < -2 bpm/mmHg tested with PE; 3 low tachycardic baroreflex (LT, BG between -1 and -2 bpm/mmHg tested with SNP and; 4 high tachycardic baroreflex (HT, BG < -2 bpm/mmHg tested with SNP. Significant differences were considered for p < 0.05. RESULTS: Approximately 37% of the rats showed a reduced bradycardic peak, bradycardic reflex and decreased bradycardic gain of baroreflex while roughly 23% had a decreased basal HR, tachycardic peak, tachycardic reflex and reduced sympathetic baroreflex gain. No significant alterations were noted with regard to basal MAP. CONCLUSION: There is variability regarding baroreflex sensitivity among WKY rats from the same laboratory.

Cardiovascular regulation during body unweighting by lower body positive pressure.

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Evans, Joyce M; Mohney, Lindsay; Wang, Siqi; Moore, Rachel K; Elayi, Samy-Claude; Stenger, Michael B; Moore, Fritz B; Knapp, Charles F

2013-11-01

We hypothesized that human cardiovascular responses to standing in reduced gravity environments, as on the Moon or Mars, could be modeled using a lower body positive pressure (LBPP) chamber. Heart rate, blood pressure, body segment fluid shifts, ECG, indexes of sympathetic, parasympathetic balance, and baroreflex control of the heart and periphery plus echocardiographic measures of cardiac function were recorded from seven men and seven women supine and standing at 100% (Earth), 40% (-Mars), and 20% (-Moon) bodyweights (BW). The fluid shifted from the chest was greater when standing at 100% BW than at 20% and 40% BW, while fluid pooled in the abdomen was similar at all BWs. Compared to moving from supine to standing at 100% BW, moving to 20% and 40% BW resulted in smaller decreases in stroke volume and pulse pressure, smaller increases in heart rate and smaller decreases in parasympathetic control of heart rate, baroreflex slope, numbers of blood pressure ramps, and much reduced indexes of sympathetic drive to the heart and periphery. However, peripheral vascular resistance, systolic pressure, and baroreflex effectiveness were elevated during 20% and 40% BW, compared to supine and standing at 100% BW. Standing at reduced bodyweight suppressed indexes of sympathetic control of heart rate and peripheral vasomotion. Regulatory responses indicated a combination of arterial and cardiopulmonary baroreflex control: mean heart rate, vasomotion, and baroreflex sensitivity appeared to be more under cardiopulmonary control while baroreflex effectiveness appeared to be driven more by the arterial baroreflex.

Assessing the strength of cardiac and sympathetic baroreflex controls via transfer entropy during orthostatic challenge

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Porta, Alberto; Marchi, Andrea; Bari, Vlasta; De Maria, Beatrice; Esler, Murray; Lambert, Elisabeth; Baumert, Mathias

2017-05-01

The study assesses the strength of the causal relation along baroreflex (BR) in humans during an incremental postural challenge soliciting the BR. Both cardiac BR (cBR) and sympathetic BR (sBR) were characterized via BR sequence approaches from spontaneous fluctuations of heart period (HP), systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and muscle sympathetic nerve activity (MSNA). A model-based transfer entropy method was applied to quantify the strength of the coupling from SAP to HP and from DAP to MSNA. The confounding influences of respiration were accounted for. Twelve young healthy subjects (20-36 years, nine females) were sequentially tilted at 0°, 20°, 30° and 40°. We found that (i) the strength of the causal relation along the cBR increases with tilt table inclination, while that along the sBR is unrelated to it; (ii) the strength of the causal coupling is unrelated to the gain of the relation; (iii) transfer entropy indexes are significantly and positively associated with simplified causality indexes derived from BR sequence analysis. The study proves that causality indexes are complementary to traditional characterization of the BR and suggests that simple markers derived from BR sequence analysis might be fruitfully exploited to estimate causality along the BR. This article is part of the themed issue `Mathematical methods in medicine: neuroscience, cardiology and pathology'.

Impaired baroreflex sensitivity, carotid stiffness, and exaggerated exercise blood pressure: a community-based analysis from the Paris Prospective Study III.

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Sharman, James E; Boutouyrie, Pierre; Perier, Marie-Cécile; Thomas, Frédérique; Guibout, Catherine; Khettab, Hakim; Pannier, Bruno; Laurent, Stéphane; Jouven, Xavier; Empana, Jean-Philippe

2018-02-14

People with exaggerated exercise blood pressure (BP) have adverse cardiovascular outcomes. Mechanisms are unknown but could be explained through impaired neural baroreflex sensitivity (BRS) and/or large artery stiffness. This study aimed to determine the associations of carotid BRS and carotid stiffness with exaggerated exercise BP. Blood pressure was recorded at rest and following an exercise step-test among 8976 adults aged 50 to 75 years from the Paris Prospective Study III. Resting carotid BRS (low frequency gain, from carotid distension rate, and heart rate) and stiffness were measured by high-precision echotracking. A systolic BP threshold of ≥ 150 mmHg defined exaggerated exercise BP and ≥140/90 mmHg defined resting hypertension (±antihypertensive treatment). Participants with exaggerated exercise BP had significantly lower BRS [median (Q1; Q3) 0.10 (0.06; 0.16) vs. 0.12 (0.08; 0.19) (ms2/mm) 2×108; P < 0.001] but higher stiffness [mean ± standard deviation (SD); 7.34 ± 1.37 vs. 6.76 ± 1.25 m/s; P < 0.001) compared to those with non-exaggerated exercise BP. However, only lower BRS (per 1SD decrement) was associated with exaggerated exercise BP among people without hypertension at rest {specifically among those with optimal BP; odds ratio (OR) 1.16 [95% confidence intervals (95% CI) 1.01; 1.33], P = 0.04 and high-normal BP; OR, 1.19 (95% CI 1.07; 1.32), P = 0.001} after adjustment for age, sex, body mass index, smoking, alcohol, total cholesterol, high-density lipoprotein cholesterol, resting heart rate, and antihypertensive medications. Impaired BRS, but not carotid stiffness, is independently associated with exaggerated exercise BP even among those with well controlled resting BP. This indicates a potential pathway from depressed neural baroreflex function to abnormal exercise BP and clinical outcomes. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For

Ovarian function after uterine artery embolisation

African Journals Online (AJOL)

2009-08-05

Aug 5, 2009 ... Objective. To evaluate ovarian function in 29 patients who underwent uterine artery embolisation ... of FSH levels, kidney function, blood count and clotting time. .... Funding: Departmental funds and routine services in hospital;.

GPER Mediates Functional Endothelial Aging in Renal Arteries.

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Meyer, Matthias R; Rosemann, Thomas; Barton, Matthias; Prossnitz, Eric R

2017-01-01

Aging is associated with impaired renal artery function, which is partly characterized by arterial stiffening and a reduced vasodilatory capacity due to excessive generation of reactive oxygen species by NADPH oxidases (Nox). The abundance and activity of Nox depends on basal activity of the heptahelical transmembrane receptor GPER; however, whether GPER contributes to age-dependent functional changes in renal arteries is unknown. This study investigated the effect of aging and Nox activity on renal artery tone in wild-type and GPER-deficient (Gper-/-) mice (4 and 24 months old). In wild-type mice, aging markedly impaired endothelium-dependent, nitric oxide (NO)-mediated relaxations to acetylcholine, which were largely preserved in renal arteries of aged Gper-/- mice. The Nox inhibitor gp91ds-tat abolished this difference by greatly enhancing relaxations in wild-type mice, while having no effect in Gper-/- mice. Contractions to angiotensin II and phenylephrine in wild-type mice were partly sensitive to gp91ds-tat but unaffected by aging. Again, deletion of GPER abolished effects of Nox inhibition on contractile responses. In conclusion, basal activity of GPER is required for the age-dependent impairment of endothelium-dependent, NO-mediated relaxation in the renal artery. Restoration of relaxation by a Nox inhibitor in aged wild-type but not Gper-/- mice strongly supports a role for Nox-derived reactive oxygen species as the underlying cause. Pharmacological blockers of GPER signaling may thus be suitable to inhibit functional endothelial aging of renal arteries by reducing Nox-derived oxidative stress and, possibly, the associated age-dependent deterioration of kidney function. © 2017 S. Karger AG, Basel.

Bradykinin receptor blockade restores the baroreflex control of renal sympathetic nerve activity in cisplatin-induced renal failure rats.

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Abdulla, M H; Duff, M; Swanton, H; Johns, E J

2016-11-01

This study investigated the effect of renal bradykinin B1 and B2 receptor blockade on the high- and low-pressure baroreceptor reflex regulation of renal sympathetic nerve activity (RSNA) in rats with cisplatin-induced renal failure. Cisplatin (5 mg/kg) or saline was given intraperitoneally 4 days prior to study. Following chloralose/urethane anaesthesia, rats were prepared for measurement of mean arterial pressure (MAP), heart rate and RSNA and received intrarenal infusions of either Lys-[des-Arg 9 , Leu 8 ]-bradykinin (LBK), a bradykinin B1 receptor blocker, or bradyzide (BZ), a bradykinin B2 receptor blocker. RSNA baroreflex gain curves and renal sympatho-inhibitory responses to volume expansion (VE) were obtained. In the control and renal failure groups, basal MAP (89 ± 3 vs. 80 ± 8 mmHg) and RSNA (2.0 ± 0.3 vs. 1.7 ± 0.6 μV.s) were similar but HR was lower in the latter group (331 ± 8 vs. 396 ± 9 beats/min). The baroreflex gain for RSNA in the renal failure rats was 39% (P renal failure rats. Intrarenal LBK infusion in the renal failure rats normalized the VE induced renal sympatho-inhibition whereas BZ only partially restored the response. These findings suggest that pro-inflammatory bradykinin acting at different receptors within the kidney generates afferent neural signals which impact differentially within the central nervous system on high- and low-pressure regulation of RSNA. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

Bronchial arteries: anatomy, function, hypertrophy, and anomalies.

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Walker, Christopher M; Rosado-de-Christenson, Melissa L; Martínez-Jiménez, Santiago; Kunin, Jeffrey R; Wible, Brandt C

2015-01-01

The two main sources of blood supply to the lungs and their supporting structures are the pulmonary and bronchial arteries. The bronchial arteries account for 1% of the cardiac output but can be recruited to provide additional systemic circulation to the lungs in various acquired and congenital thoracic disorders. An understanding of bronchial artery anatomy and function is important in the identification of bronchial artery dilatation and anomalies and the formulation of an appropriate differential diagnosis. Visualization of dilated bronchial arteries at imaging should alert the radiologist to obstructive disorders that affect the pulmonary circulation and prompt the exclusion of diseases that produce or are associated with pulmonary artery obstruction, including chronic infectious and/or inflammatory processes, chronic thromboembolic disease, and congenital anomalies of the thorax (eg, proximal interruption of the pulmonary artery). Conotruncal abnormalities, such as pulmonary atresia with ventricular septal defect, are associated with systemic pulmonary supply provided by aortic branches known as major aortopulmonary collaterals, which originate in the region of the bronchial arteries. Bronchial artery malformation is a rare left-to-right or left-to-left shunt characterized by an anomalous connection between a bronchial artery and a pulmonary artery or a pulmonary vein, respectively. Bronchial artery interventions can be used successfully in the treatment of hemoptysis, with a low risk of adverse events. Multidetector computed tomography helps provide a vascular road map for the interventional radiologist before bronchial artery embolization. RSNA, 2015

Baroreflex sensitivity in the elderly : influence of age, breathing and spectral methods

NARCIS (Netherlands)

Gerritsen, J; TenVoorde, B J; Dekker, J M; Kostense, P J; Bouter, L M; Heethaar, R M

2000-01-01

Baroreflex sensitivity (BRS) has been proposed as a diagnostic parameter for neurological disorders and as a survival-prognosis parameter in diabetic and cardiac patients. Therefore reference values and the reproducibility of BRS were assessed, taking into account the possible influence of age,

Dll4-Notch signaling determines the formation of native arterial collateral networks and arterial function in mouse ischemia models.

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Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C; Iruela-Arispe, M Luisa; Nih, Lina R; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand

2013-04-01

Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4(+/-) mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4(+/-) mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality.

Dll4-Notch signaling determines the formation of native arterial collateral networks and arterial function in mouse ischemia models

Science.gov (United States)

Cristofaro, Brunella; Shi, Yu; Faria, Marcella; Suchting, Steven; Leroyer, Aurelie S.; Trindade, Alexandre; Duarte, Antonio; Zovein, Ann C.; Iruela-Arispe, M. Luisa; Nih, Lina R.; Kubis, Nathalie; Henrion, Daniel; Loufrani, Laurent; Todiras, Mihail; Schleifenbaum, Johanna; Gollasch, Maik; Zhuang, Zhen W.; Simons, Michael; Eichmann, Anne; le Noble, Ferdinand

2013-01-01

Arteriogenesis requires growth of pre-existing arteriolar collateral networks and determines clinical outcome in arterial occlusive diseases. Factors responsible for the development of arteriolar collateral networks are poorly understood. The Notch ligand Delta-like 4 (Dll4) promotes arterial differentiation and restricts vessel branching. We hypothesized that Dll4 may act as a genetic determinant of collateral arterial networks and functional recovery in stroke and hind limb ischemia models in mice. Genetic loss- and gain-of-function approaches in mice showed that Dll4-Notch signaling restricts pial collateral artery formation by modulating arterial branching morphogenesis during embryogenesis. Adult Dll4+/- mice showed increased pial collateral numbers, but stroke volume upon middle cerebral artery occlusion was not reduced compared with wild-type littermates. Likewise, Dll4+/- mice showed reduced blood flow conductance after femoral artery occlusion, and, despite markedly increased angiogenesis, tissue ischemia was more severe. In peripheral arteries, loss of Dll4 adversely affected excitation-contraction coupling in arterial smooth muscle in response to vasopressor agents and arterial vessel wall adaption in response to increases in blood flow, collectively contributing to reduced flow reserve. We conclude that Dll4-Notch signaling modulates native collateral formation by acting on vascular branching morphogenesis during embryogenesis. Dll4 furthermore affects tissue perfusion by acting on arterial function and structure. Loss of Dll4 stimulates collateral formation and angiogenesis, but in the context of ischemic diseases such beneficial effects are overruled by adverse functional changes, demonstrating that ischemic recovery is not solely determined by collateral number but rather by vessel functionality. PMID:23533173

Arterial stiffness and functional outcome in acute ischemic stroke.

Science.gov (United States)

Lee, Yeong-Bae; Park, Joo-Hwan; Kim, Eunja; Kang, Chang-Ki; Park, Hyeon-Mi

2014-03-01

Arterial stiffness is a common change associated with aging and can be evaluated by measuring pulse wave velocity (PWV) between sites in the arterial tree, with the stiffer artery having the higher PWV. Arterial stiffness is associated with the risk of stroke in the general population and of fatal stroke in hypertensive patients. This study is to clarify whether PWV value predicts functional outcome of acute ischemic stroke. ONE HUNDRED PATIENTS WERE ENROLLED WITH A DIAGNOSIS OF ACUTE ISCHEMIC STROKE AND CATEGORIZED INTO TWO GROUPS: large-artery atherosclerosis (LAAS) or small vessel disease (SVD) subtype of Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification. Each group was divided into two sub-groups based on the functional outcome of acute ischemic stroke, indicated by modified Rankin Scale (mRS) at discharge. Poor functional outcome group was defined as a mRS ≥ 3 at discharge. Student's t-test or Mann-Whitney U-test were used to compare maximal brachial-ankle PWV (baPWV) values. Twenty-four patients whose state was inadequate to assess baPWV or mRS were excluded. There were 38 patients with good functional outcome (mRS vs. 1,789.80 ± 421.91, p = 0.022), while there was no significant difference of baPWV among patients with LAAS subtype (2,071.76 ± 618.42 vs. 1,878.00 ± 365.35, p = 0.579). Arterial stiffness indicated by baPWV is associated with the functional outcome of acute ischemic stroke. This finding suggests that measurement of baPWV predicts functional outcome in patients with stroke especially those whose TOAST classification was confirmed as SVD subtype.

Cone pathway function in relation to asymmetric carotid artery stenosis

DEFF Research Database (Denmark)

Kofoed, Peter Kristian; Munch, Inger Christine; Holfort, Stig K

2013-01-01

Purpose:  To examine retinal function in relation to retinal perfusion pressure in patients with carotid artery stenosis. Methods:  Thirteen patients with carotid artery stenosis without clinical eye disease underwent assessment of ophthalmic artery systolic blood pressure (OSP) by ocular...... pneumoplethysmography, carotid artery obstructive disease by ultrasonography, intraocular pressure by applanation tonometry, retinal perfusion by fluorescein angiography and retinal function by multifocal electroretinography (mfERG). Data analysis compared the eye on the most stenotic side with the fellow eye...... pressure (p = 0.0028, 0.011, 0.041 for N1, P1, N2 implicit times, respectively, and p = 0.0086, 0.016, 0.040 for N1, P1, N2 for amplitudes, respectively, corrected for OSP). Conclusion:  Cone function deviation was observed in clinically healthy eyes on the side with highest degree of carotid artery...

Physical exercise performance in temperate and warm environments is decreased by an impaired arterial baroreflex.

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Washington Pires

Full Text Available The present study aimed to investigate whether running performance in different environments is dependent on intact arterial baroreceptor reflexes. We also assessed the exercise-induced cardiovascular and thermoregulatory responses in animals lacking arterial baroafferent signals. To accomplish these goals, male Wistar rats were subjected to sinoaortic denervation (SAD or sham surgery (SHAM and had a catheter implanted into the ascending aorta to record arterial pressure and a telemetry sensor implanted in the abdominal cavity to record core temperature. After recovering from these surgeries, the animals were subjected to constant- or incremental-speed exercises performed until the voluntary interruption of effort under temperate (25° C and warm (35° C conditions. During the constant-speed exercises, the running time until the rats were fatigued was shorter in SAD rats in both environments. Although the core temperature was not significantly different between the groups, tail skin temperature was higher in SAD rats under temperate conditions. The denervated rats also displayed exaggerated increases in blood pressure and double product compared with the SHAM rats; in particular, in the warm environment, these exaggerated cardiovascular responses in the SAD rats persisted until they were fatigued. These SAD-mediated changes occurred in parallel with increased variability in the very low and low components of the systolic arterial pressure power spectrum. The running performance was also affected by SAD during the incremental-speed exercises, with the maximal speed attained being decreased by approximately 20% in both environments. Furthermore, at the maximal power output tolerated during the incremental exercises, the mean arterial pressure, heart rate and double product were exaggerated in the SAD relative to SHAM rats. In conclusion, the chronic absence of the arterial baroafferents accelerates exercise fatigue in temperate and warm

The Neural Baroreflex Pathway in Subjects With Metabolic Syndrome

OpenAIRE

Zanoli, Luca; Empana, Jean-Philippe; Estrugo, Nicolas; Escriou, Guillaume; Ketthab, Hakim; Pruny, Jean-Francois; Castellino, Pietro; Laude, Dominique; Thomas, Frederique; Pannier, Bruno; Jouven, Xavier; Boutouyrie, Pierre; Laurent, Stephane

2016-01-01

Abstract The mechanisms that link metabolic syndrome (MetS) to increased cardiovascular risk are incompletely understood. We examined whether MetS is associated with the neural baroreflex pathway (NBP) and whether any such associations are independent of blood pressure values. This study involved the cross-sectional analysis of data on 2835 subjects aged 50 to 75 years from the Paris Prospective Study 3. The prevalence of MetS was defined according to the American Heart Association/National H...

Arterial Stiffness and Functional Outcome in Acute Ischemic Stroke

OpenAIRE

Lee, Yeong-Bae; Park, Joo-Hwan; Kim, Eunja; Kang, Chang-Ki; Park, Hyeon-Mi

2014-01-01

Objective Arterial stiffness is a common change associated with aging and can be evaluated by measuring pulse wave velocity (PWV) between sites in the arterial tree, with the stiffer artery having the higher PWV. Arterial stiffness is associated with the risk of stroke in the general population and of fatal stroke in hypertensive patients. This study is to clarify whether PWV value predicts functional outcome of acute ischemic stroke. Methods One hundred patients were enrolled with a diagnosi...

Influence of a multideficient diet from northeastern Brazil on resting blood pressure and baroreflex sensitivity in conscious, freely moving rats

Directory of Open Access Journals (Sweden)

F.M.F. Monteiro

2001-02-01

Full Text Available The "regional basic diet" or RBD is a multideficient diet (providing 8% protein which is known to produce dietary deficiencies in some populations in northeastern Brazil. The present study investigated the effects of RBD-induced malnutrition on resting blood pressure and baroreflex sensitivity in conscious rats. Malnourished rats were obtained by feeding dams the RBD during mating and pregnancy (RBD-1 group or during nursing and a 10-day period after weaning (RBD-2 group. At 90 days of age, only RBD-2 rats weighed significantly (P<0.001 less than control rats born to dams fed a standard commercial diet (23% protein during pregnancy and nursing. Baseline mean arterial pressure and heart rate of both RBD-1 and RBD-2 rats were comparable to those of controls. The slopes for both reflex bradycardia and tachycardia (bpm/mmHg induced by intravenous phenylephrine and sodium nitroprusside, respectively, were unchanged in either RBD-1 (-2.08 ± 0.11 and -3.10 ± 0.43, respectively or RBD-2 (-2.32 ± 0.30 and -3.73 ± 0.53, respectively rats, when compared to controls (-2.09 ± 0.10 and -3.17 ± 0.33, respectively. This study shows that, after a prolonged period of nutritional recovery, the patterns of resting blood pressure and baroreflex sensitivity of both pre- and postnatally malnourished rats were similar to those of controls. The decreased body weight and the tendency to increased reflex tachycardia in RBD-2 rats may suggest that this type of maternal malnutrition during lactation is more critical than during pregnancy.

RESTING SYMPATHETIC BAROREFLEX SENSITIVITY IN SUBJECTS WITH LOW AND HIGH TOLERANCE TO CENTRAL HYPOVOLEMIA INDUCED BY LOWER BODY NEGATIVE PRESSURE

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Carmen eHinojosa-Laborde

2014-06-01

Full Text Available Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock. The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA and sympathetic baroreflex sensitivity (BRS are attenuated in male and female subjects who have low tolerance (LT to central hypovolemia induced by lower body negative pressure (LBNP. MSNA and diastolic arterial pressure (DAP were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms. LT subjects experienced presyncopal symptoms prior to completing LBNP of -60 mm Hg, and subjects with high tolerance (HT experienced presyncopal symptoms after completing LBNP after -60 mmHg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n= 9; HT: n=28, and BRS was not different between LT and HT (-1.8 ± 0.3 vs. -2.2 ± 0.2 bursts•(100 beats-1•mmHg-1, p=0.29. We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS.

Cardiac impairment evaluated by transesophageal echocardiography and invasive measurements in rats undergoing sinoaortic denervation.

Directory of Open Access Journals (Sweden)

Raquel A Sirvente

Full Text Available BACKGROUND: Sympathetic hyperactivity may be related to left ventricular (LV dysfunction and baro- and chemoreflex impairment in hypertension. However, cardiac function, regarding the association of hypertension and baroreflex dysfunction, has not been previously evaluated by transesophageal echocardiography (TEE using intracardiac echocardiographic catheter. METHODS AND RESULTS: We evaluated exercise tests, baroreflex sensitivity and cardiovascular autonomic control, cardiac function, and biventricular invasive pressures in rats 10 weeks after sinoaortic denervation (SAD. The rats (n = 32 were divided into 4 groups: 16 Wistar (W with (n = 8 or without SAD (n = 8 and 16 spontaneously hypertensive rats (SHR with (n = 8 or without SAD (SHRSAD (n = 8. Blood pressure (BP and heart rate (HR did not change between the groups with or without SAD; however, compared to W, SHR groups had higher BP levels and BP variability was increased. Exercise testing showed that SHR had better functional capacity compared to SAD and SHRSAD. Echocardiography showed left ventricular (LV concentric hypertrophy; segmental systolic and diastolic biventricular dysfunction; indirect signals of pulmonary arterial hypertension, mostly evident in SHRSAD. The end-diastolic right ventricular (RV pressure increased in all groups compared to W, and the end-diastolic LV pressure increased in SHR and SHRSAD groups compared to W, and in SHRSAD compared to SAD. CONCLUSIONS: Our results suggest that baroreflex dysfunction impairs cardiac function, and increases pulmonary artery pressure, supporting a role for baroreflex dysfunction in the pathogenesis of hypertensive cardiac disease. Moreover, TEE is a useful and feasible noninvasive technique that allows the assessment of cardiac function, particularly RV indices in this model of cardiac disease.

Baroreflex Coupling Assessed by Cross-Compression Entropy

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Andy Schumann

2017-05-01

Full Text Available Estimating interactions between physiological systems is an important challenge in modern biomedical research. Here, we explore a new concept for quantifying information common in two time series by cross-compressibility. Cross-compression entropy (CCE exploits the ZIP data compression algorithm extended to bivariate data analysis. First, time series are transformed into symbol vectors. Symbols of the target time series are coded by the symbols of the source series. Uncoupled and linearly coupled surrogates were derived from cardiovascular recordings of 36 healthy controls obtained during rest to demonstrate suitability of this method for assessing physiological coupling. CCE at rest was compared to that of isometric handgrip exercise. Finally, spontaneous baroreflex interaction assessed by CCEBRS was compared between 21 patients suffering from acute schizophrenia and 21 matched controls. The CCEBRS of original time series was significantly higher than in uncoupled surrogates in 89% of the subjects and higher than in linearly coupled surrogates in 47% of the subjects. Handgrip exercise led to sympathetic activation and vagal inhibition accompanied by reduced baroreflex sensitivity. CCEBRS decreased from 0.553 ± 0.030 at rest to 0.514 ± 0.035 during exercise (p < 0.001. In acute schizophrenia, heart rate, and blood pressure were elevated. Heart rate variability indicated a change of sympathovagal balance. The CCEBRS of patients with schizophrenia was reduced compared to healthy controls (0.546 ± 0.042 vs. 0.507 ± 0.046, p < 0.01 and revealed a decrease of blood pressure influence on heart rate in patients with schizophrenia. Our results indicate that CCE is suitable for the investigation of linear and non-linear coupling in cardiovascular time series. CCE can quantify causal interactions in short, noisy and non-stationary physiological time series.

Teaching baroreflex physiology to medical students

DEFF Research Database (Denmark)

Berg, Ronan M G; Plovsing, Ronni R.; Damgaard, Morten

2012-01-01

quizzes individually and in groups with conventional teaching on the immediate learning during a laboratory exercise. We implemented two quizzes in a mandatory 4-h laboratory exercise on baroreflex physiology. A total of 155 second-year medical students were randomized to solve quizzes individually...... (intervention group I, n = 57), in groups of three to four students (intervention group II, n = 56), or not to perform any quizzes (control; intervention group III, n = 42). After the laboratory exercise, all students completed an individual test, which encompassed two recall questions, two intermediate...... questions, and two integrated questions. The integrated questions were of moderate and advanced difficulty, respectively. Finally, students completed an evaluation form. Intervention group I reached the highest total test scores and proved best at answering the integrated question of advanced difficulty...

Monosodium glutamate neonatal treatment induces cardiovascular autonomic function changes in rodents

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Signorá Peres Konrad

2012-10-01

Full Text Available OBJECTIVES: The aim of this study was to evaluate cardiovascular autonomic function in a rodent obesity model induced by monosodium glutamate injections during the first seven days of life. METHOD: The animals were assigned to control (control, n = 10 and monosodium glutamate (monosodium glutamate, n = 13 groups. Thirty-three weeks after birth, arterial and venous catheters were implanted for arterial pressure measurements, drug administration, and blood sampling. Baroreflex sensitivity was evaluated according to the tachycardic and bradycardic responses induced by sodium nitroprusside and phenylephrine infusion, respectively. Sympathetic and vagal effects were determined by administering methylatropine and propranolol. RESULTS: Body weight, Lee index, and epididymal white adipose tissue values were higher in the monosodium glutamate group in comparison to the control group. The monosodium glutamate-treated rats displayed insulin resistance, as shown by a reduced glucose/insulin index (-62.5%, an increased area under the curve of total insulin secretion during glucose overload (39.3%, and basal hyperinsulinemia. The mean arterial pressure values were higher in the monosodium glutamate rats, whereas heart rate variability (>7 times, bradycardic responses (>4 times, and vagal (~38% and sympathetic effects (~36% were reduced as compared to the control group. CONCLUSION: Our results suggest that obesity induced by neonatal monosodium glutamate treatment impairs cardiac autonomic function and most likely contributes to increased arterial pressure and insulin resistance.

Additive effects of heating and exercise on baroreflex control of heart rate in healthy males.

Science.gov (United States)

Peçanha, Tiago; Forjaz, Cláudia L M; Low, David A

2017-12-01

This study assessed the additive effects of passive heating and exercise on cardiac baroreflex sensitivity (cBRS) and heart rate variability (HRV). Twelve healthy young men (25 ± 1 yr, 23.8 ± 0.5 kg/m 2 ) randomly underwent two experimental sessions: heat stress (HS; whole body heat stress using a tube-lined suit to increase core temperature by ~1°C) and normothermia (NT). Each session was composed of a preintervention rest (REST1); HS or NT interventions; postintervention rest (REST2); and 14 min of cycling exercise [7 min at 40%HR reserve (EX1) and 7 min at 60%HR reserve (EX2)]. Heart rate and finger blood pressure were continuously recorded. cBRS was assessed using the sequence (cBRS SEQ ) and transfer function (cBRS TF ) methods. HRV was assessed using the indexes standard deviation of RR intervals (SDNN) and root mean square of successive RR intervals (RMSSD). cBRS and HRV were not different between sessions during EX1 and EX2 (i.e., matched heart rate conditions: EX1 = 116 ± 3 vs. 114 ± 3 and EX2 = 143 ± 4 vs. 142 ± 3 beats/min but different workloads: EX1 = 50 ± 9 vs. 114 ± 8 and EX2 = 106 ± 10 vs. 165 ± 8 W; for HS and NT, respectively; P heat stress to exercise does not affect cBRS and HRV. Alternatively, in workload-matched conditions, the addition of heat to exercise results in reduced cBRS and HRV compared with exercise in normothermia. NEW & NOTEWORTHY The present study assessed cardiac baroreflex sensitivity during the combination of heat and exercise stresses. This is the first study to show that prior whole body passive heating reduces cardiac baroreflex sensitivity and autonomic modulation of heart rate during exercise. These findings contribute to the better understanding of the role of thermoregulation on cardiovascular regulation during exercise.

Baroreflex dysfunction and augmented sympathetic nerve responses during mental stress in veterans with post-traumatic stress disorder.

Science.gov (United States)

Park, Jeanie; Marvar, Paul J; Liao, Peizhou; Kankam, Melanie L; Norrholm, Seth D; Downey, Ryan M; McCullough, S Ashley; Le, Ngoc-Anh; Rothbaum, Barbara O

2017-07-15

Patients with post-traumatic stress disorder (PTSD) are at a significantly higher risk of developing hypertension and cardiovascular disease. The mechanisms underlying this increased risk are not known. Studies have suggested that PTSD patients have an overactive sympathetic nervous system (SNS) that could contribute to cardiovascular risk; however, sympathetic function has not previously been rigorously evaluated in PTSD patients. Using direct measurements of sympathetic nerve activity and pharmacological manipulation of blood pressure, we show that veterans with PTSD have augmented SNS and haemodynamic reactivity during both combat-related and non-combat related mental stress, impaired sympathetic and cardiovagal baroreflex sensitivity, and increased inflammation. Identifying the mechanisms contributing to increased cardiovascular (CV) risk in PTSD will pave the way for developing interventions to improve sympathetic function and reduce CV risk in these patients. Post-traumatic stress disorder (PTSD) is associated with increased cardiovascular (CV) risk. We tested the hypothesis that PTSD patients have augmented sympathetic nervous system (SNS) and haemodynamic reactivity during mental stress, as well as impaired arterial baroreflex sensitivity (BRS). Fourteen otherwise healthy Veterans with combat-related PTSD were compared with 14 matched Controls without PTSD.  Muscle sympathetic nerve activity (MSNA), continuous blood pressure (BP) and electrocardiography were measured at baseline, as well as during two types of mental stress:  combat-related mental stress using virtual reality combat exposure (VRCE) and non-combat related stress using mental arithmetic (MA). A cold pressor test (CPT) was administered for comparison. BRS was tested using pharmacological manipulation of BP via the Modified Oxford technique at rest and during VRCE. Blood samples were analysed for inflammatory biomarkers. Baseline characteristics, MSNA and haemodynamics were similar between

Reduced Baroreflex Sensitivity in Cluster Headache Patients

DEFF Research Database (Denmark)

Barloese, Mads C J; Mehlsen, Jesper; Brinth, Louise

2015-01-01

by baroreflex sensitivity (BRS) in CH patients. METHODS: Twenty-six active CH patients and an equal number of age-, sex-, and BMI-matched controls underwent head-up tilt table test and BRS was determined by the sequence method. RESULTS: Compared with controls, patients exhibited a blunted reactivity of RR...... patients who had not (n = 13, 16.0 ms/mmHg, P = .1523). In the tilted position, the drop in SBP at the carotid sinuses was higher in patients who had recently suffered an attack. Despite this, they exhibited a less marked shortening of RR intervals when compared with patients who had been attack free...... of the autonomic nervous system or in the central relay of impulses from the baroreceptors....

Transcutaneous measurement of the arterial input function in positron emission tomography

International Nuclear Information System (INIS)

Litton, J.E.; Eriksson, L.

1990-01-01

Positron emission tomography (PET) provides a powerful tool in medical research. Biochemical function can be both precisely localized and quantitatively measured. To achieve reliable quantitation it is necessary to know the time course of activity concentration in the arterial blood during the measurement. In this study the arterial blood curve from the brachial artery is compared to the activity measured in the internal carotid artery with a new transcutaneous detector

[Changes of brain function and cognitive function after carotid artery stenting].

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Lu, Z X; Deng, G; Wei, H L; Zhao, G F; Wen, L Z; Chen, X

2017-10-24

Objective: To investigate the effect of carotid artery stenting(CAS) on cognitive function and brain function based on changes of a battery of neuropsychological tests and magnetic resonance imaging. Methods: Thirty-three patients were included with 17 in the stent-placement group and 16 in the control group (receiving medical treatment), among whom, the unilateral or bilateral severe internal carotid artery stenosis was confirmed by cerebral vascular angiography in the department of Interventional Radiology and Vascular Surgery of Zhongda Hospital Southeast University from June 2015 to September 2016.Neuropsychological tests and rest-state blood oxygenation level dependent fMRI were performed at the baseline and six months follow-up.The baseline characteristics and follow-up changes were compared in each group. Results: The overall cognitive function of the stent-placement group was statistically significantly improved ( P function, memory, attention and other aspects.The value of amplitude of low-frequency fluctuation(ALFF) showed statistically significant increase ( P left prefrontal cortex ( t =5.861 3, P left superior parietal lobe( t =5.601 2, P left retrosplenial cingulate cortex( t =-5.590 4, P left insular cortex ( t =-6.340 8, P right insular cortex ( t =-8.129 9, P left dorsal anterior cingulate cortex ( t =-5.584 8, P 0.05, Alphasim correction)between baseline and follow-up results in control group.Besides, the ALFF changes of the left insular cortex ( r =-0.591, P =0.033) and bilateral motor cortical area ( r =-0.659, P =0.014) were negatively correlated with auditory verb learning test (AVLT) score changes.The ALFF change of bilateral motor cortical area was negatively correlated with the AVLT-delay score change ( r =-0.588, P =0.034). And the ALFF change on right insular cortex and the frontal assessment battery (FAB) score change was positively correlated ( r =0.638, P =0.025). Conclusions: The overall cognitive function of patients with carotid

Autonomic and Vascular Control in Prehypertensive Subjects with a Family History of Arterial Hypertension

Directory of Open Access Journals (Sweden)

Josária Ferraz Amaral

2018-02-01

Full Text Available Abstract Background: Individuals with a family history of systemic arterial hypertension (FHSAH and / or prehypertension have a higher risk of developing this pathology. Objective: To evaluate the autonomic and vascular functions of prehypertensive patients with FHSAH. Methods: Twenty-five young volunteers with FHSAH, 14 normotensive and 11 prehypertensive subjects were submitted to vascular function evaluation by forearm vascular conductance(VC during resting and reactive hyperemia (Hokanson® and cardiac and peripheral autonomic modulation, quantified, respectively, by spectral analysis of heart rate (ECG and systolic blood pressure (SBP (FinometerPRO®. The transfer function analysis was used to measure the gain and response time of baroreflex. The statistical significance adopted was p ≤ 0.05. Results: Pre-hypertensive individuals, in relation to normotensive individuals, have higher VC both at rest (3.48 ± 1.26 vs. 2.67 ± 0.72 units, p = 0.05 and peak reactive hyperemia (25, 02 ± 8.18 vs. 18.66 ± 6.07 units, p = 0.04. The indices of cardiac autonomic modulation were similar between the groups. However, in the peripheral autonomic modulation, greater variability was observed in prehypertensive patients compared to normotensive individuals (9.4 [4.9-12.7] vs. 18.3 [14.8-26.7] mmHg2; p < 0.01 and higher spectral components of very low (6.9 [2.0-11.1] vs. 13.5 [10.7-22.4] mmHg2, p = 0.01 and low frequencies (1.7 [1.0-3.0] vs. 3.0 [2.0-4.0] mmHg2, p = 0.04 of SBP. Additionally, we observed a lower gain of baroreflex control in prehypertensive patients compared to normotensive patients (12.16 ± 4.18 vs. 18.23 ± 7.11 ms/mmHg, p = 0.03, but similar delay time (-1.55 ± 0.66 vs. -1.58 ± 0.72 s, p = 0.90. Conclusion: Prehypertensive patients with FHSAH have autonomic dysfunction and increased vascular conductance when compared to normotensive patients with the same risk factor.

The effects of postural changes of baroreflex gain in normal and hypertensive pregnancies.

Science.gov (United States)

Miyake, Yoshiaki; Ohnishi, Miyako; Fujii, T K; Yamamoto, Tatsuo; Yoneda, Chika; Takahashi, Sachie; Ichimaru, Yuhei

2002-01-01

In order to understand the changes of baroreflex gain due to postural changes in normal pregnancies, we measured percentage changes (% changes) in blood pressure (SBP, DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) as well as cardiac autonomic nervous function (HF as an index of parasympathetic and LF/HF as an index of sympathetic function) and compared these parameters in normal pregnancies with those found in hypertensive pregnancies, such as chronic hypertensive (CHP) and severe preeclamptic pregnancies (PE), in late pregnancy (after 32 wks). When the position was changed from supine to standing in normal and non-pregnant women, the % changes of HR, DBP, TPR and LF/HF were increased and SBP, SV, CO and HF were decreased. The % changes of these parameters, however, were gradually decreased as pregnancy progressed, especially after 20-24 wks of gestation. In hypertensive pregnancies, however, even in late pregnancy, the decreased SBP and increased TPR was still observed and the profound decrease of CO and SV and increase of TPR were characteristic in PE when compared to CHP.

Optimal Testing Intervals in the Squatting Test to Determine Baroreflex Sensitivity

OpenAIRE

Ishitsuka, S.; Kusuyama, N.; Tanaka, M.

2014-01-01

The recently introduced “squatting test” (ST) utilizes a simple postural change to perturb the blood pressure and to assess baroreflex sensitivity (BRS). In our study, we estimated the reproducibility of and the optimal testing interval between the STs in healthy volunteers. Thirty-four subjects free of cardiovascular disorders and taking no medication were instructed to perform the repeated ST at 30-sec, 1-min, and 3-min intervals in duplicate in a random sequence, while the systolic blood p...

Resting spontaneous baroreflex sensitivity and cardiac autonomic control in anabolic androgenic steroid users

OpenAIRE

Santos, Marcelo R. dos; Sayegh, Ana L.C.; Armani, Rafael; Costa-Hong, Valéria; Souza, Francis R. de; Toschi-Dias, Edgar; Bortolotto, Luiz A.; Yonamine, Mauricio; Negrão, Carlos E.; Alves, Maria-Janieire N.N.

2018-01-01

OBJECTIVES: Misuse of anabolic androgenic steroids in athletes is a strategy used to enhance strength and skeletal muscle hypertrophy. However, its abuse leads to an imbalance in muscle sympathetic nerve activity, increased vascular resistance, and increased blood pressure. However, the mechanisms underlying these alterations are still unknown. Therefore, we tested whether anabolic androgenic steroids could impair resting baroreflex sensitivity and cardiac sympathovagal control. In addition, ...

Bidirectional interactions between the baroreceptor reflex and arousal: an update.

Science.gov (United States)

Silvani, Alessandro; Calandra-Buonaura, Giovanna; Benarroch, Eduardo E; Dampney, Roger A L; Cortelli, Pietro

2015-02-01

Studies involving genetic engineering on animal models and mathematical analysis of cardiovascular signals on humans are shedding new light on the interactions between the arterial baroreceptor reflex (baroreflex) and arousal. Baroreceptor stimulation, if very mild or performed under anaesthesia, may inhibit cortical arousal. However, substantial increases or decreases in baroreflex activation cause arousal in animal models and human subjects in physiological conditions. On the other hand, cardiovascular changes during autonomic arousals and between the states of wakefulness and sleep involve changes in the baroreflex set point and balance with central autonomic commands. Neural connectivity and functional data suggest that the nucleus of the solitary tract, adrenergic C1 neurons of the medulla, and the parabrachial nucleus of the pons mediate the bidirectional interactions between the baroreflex and arousal. These interactions may constitute a positive feedback loop that facilitates sharp and coordinated brain state and autonomic transitions upon arousal: upon arousal, central autonomic commands may increase blood pressure, thereby loading baroreceptors and further increasing arousal. Anomalies of this feedback loop may play a role in the pathophysiology of disease conditions associated with cardiovascular and sleep-wake cycle alterations. These conditions include: obstructive sleep apnoea syndrome, with its association with excessive daytime sleepiness and baroreflex impairment; and insomnia, with its association with autonomic hyperarousal and hypertension. When faced with disorders associated with cardiovascular and sleep-wake cycle alterations, clinical reasoning should entertain the possibility that both conditions are strongly influenced by anomalies of baroreflex function. Copyright © 2014 Elsevier B.V. All rights reserved.

Gender Differences in Baroreflex Sensitivity after Bed Rest

Science.gov (United States)

Arzeno, Natalia M.; Stenger, M. B.; Ribeiro, L. C.; Lee, S. M.; Platts, S. H.

2009-01-01

Two potential contributing factors to post-spaceflight orthostatic intolerance are decreases in baroreflex sensitivity (BRS) and sympathetic nervous system response. The purpose of this study was to examine the shape of the BRS curve and sympathetic response to a wide range of blood pressures (BP) before and during 6 head-down bed rest (BR). METHODS: Normal volunteers were tested one day before BR (20M, 1 0F) and near BR days 30 (20M, 10F), 60 (16M, 8F), and 90 (1 0M, 5F). BP was pharmacologically manipulated by 10-min infusions of phenylephrine (PE) and sodium nitroprusside (SNP) at 3 increasing concentrations with a 20-min rest between PE and SNP. Electrocardiogram and continuous finger blood pressure were recorded. A blood sample was drawn at the end of each infusion to measure plasma norepinephrine levels. The spontaneous baroreflex slope (SBS), a measure of BRS, was calculated as the slope of a sequence of 3 or more beats in which the systolic BP (SBP) and following R-R interval (RR) both increased or decreased. The data included saturated responses at the upper but not the lower end of the BP range. Mean response curves were constructed using second-order mixed model analysis. Results are based on term significance in the models. RESULTS RR: RR was lower during BR than pre BR (pgenders were modeled by a linear response; compared to males, females had an attenuated (lower slope) RR response to changes in SBP (p=0.031). SBS: SBS vs SBP analysis showed a lower SBS during BR (pgender and BR. Not only do gender and BR baseline differences exist, but gender and BR also influence the slope and saturation of the BRS curves. Attenuated and saturating RR and SBS responses, as well as differences in baseline values, may contribute to the higher rates of orthostatic intolerance in women and after bed rest.

Peritumoral Artery Scoring System: a Novel Scoring System to Predict Renal Function Outcome after Laparoscopic Partial Nephrectomy.

Science.gov (United States)

Zhang, Ruiyun; Wu, Guangyu; Huang, Jiwei; Shi, Oumin; Kong, Wen; Chen, Yonghui; Xu, Jianrong; Xue, Wei; Zhang, Jin; Huang, Yiran

2017-06-06

The present study aimed to assess the impact of peritumoral artery characteristics on renal function outcome prediction using a novel Peritumoral Artery Scoring System based on computed tomography arteriography. Peritumoral artery characteristics and renal function were evaluated in 220 patients who underwent laparoscopic partial nephrectomy and then validate in 51 patients with split and total glomerular filtration rate (GFR). In particular, peritumoral artery classification and diameter were measured to assign arteries into low, moderate, and high Peritumoral Artery Scoring System risk categories. Univariable and multivariable logistic regression analyses were then used to determine risk factors for major renal functional decline. The Peritumoral Artery Scoring System and four other nephrometry systems were compared using receiver operating characteristic curve analysis. The Peritumoral Artery Scoring System was significantly superior to the other systems for predicting postoperative renal function decline (p system was a superior independent predictor of estimated glomerular filtration rate (eGFR) decline (area-under-the-curve = 0.865, p renal function outcome after laparoscopic partial nephrectomy.

Arterial stiffness and wave reflection: sex differences and relationship with left ventricular diastolic function.

Science.gov (United States)

Russo, Cesare; Jin, Zhezhen; Palmieri, Vittorio; Homma, Shunichi; Rundek, Tatjana; Elkind, Mitchell S V; Sacco, Ralph L; Di Tullio, Marco R

2012-08-01

Increased arterial stiffness and wave reflection have been reported in heart failure with normal ejection fraction (HFNEF) and in asymptomatic left ventricular (LV) diastolic dysfunction, a precursor of HFNEF. It is unclear whether women, who have higher frequency of HFNEF, are more vulnerable than men to the deleterious effects of arterial stiffness on LV diastolic function. We investigated, in a large community-based cohort, whether sex differences exist in the relationship among arterial stiffness, wave reflection, and LV diastolic function. Arterial stiffness and wave reflection were assessed in 983 participants from the Cardiovascular Abnormalities and Brain Lesions study using applanation tonometry. The central pulse pressure/stroke volume index, total arterial compliance, pulse pressure amplification, and augmentation index were used as parameters of arterial stiffness and wave reflection. LV diastolic function was evaluated by 2-dimensional echocardiography and tissue-Doppler imaging. Arterial stiffness and wave reflection were greater in women compared with men, independent of body size and heart rate (all Pfunction in both sexes. Further adjustment for cardiovascular risk factors attenuated these relationships; however, a higher central pulse pressure/stroke volume index predicted LV diastolic dysfunction in women (odds ratio, 1.54; 95% confidence intervals, 1.03 to 2.30) and men (odds ratio, 2.09; 95% confidence interval, 1.30 to 3.39), independent of other risk factors. In conclusion, in our community-based cohort study, higher arterial stiffness was associated with worse LV diastolic function in men and women. Women's higher arterial stiffness, independent of body size, may contribute to their greater susceptibility to develop HFNEF.

Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight

NARCIS (Netherlands)

Di Rienzo, Marco; Castiglioni, Paolo; Iellamo, Ferdinando; Volterrani, Maurizio; Pagani, Massimo; Mancia, Giuseppe; Karemaker, John M.; Parati, Gianfranco

2008-01-01

Di Rienzo M, Castiglioni P, Iellamo F, Volterrani M, Pagani M, Mancia G, Karemaker JM, Parati G. Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight. J Appl Physiol 105: 1569-1575, 2008. First published August 28, 2008;

Chronic hindlimb ischemia impairs functional vasodilation and vascular reactivity in mouse feed arteries

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Trevor R Cardinal

2011-12-01

Full Text Available Vasodilation of lower leg arterioles is impaired in animal models of chronic peripheral ischemia. In addition to arterioles, feed arteries are a critical component of the vascular resistance network, accounting for as much as 50% of the pressure drop across the arterial circulation. Despite the critical importance of feed arteries in blood flow control, the impact of ischemia on feed artery vascular reactivity is unknown. At 14 days following unilateral resection of the femoral-saphenous artery-vein pair, functional vasodilation of the profunda femoris artery was severely impaired, 11 ± 9% versus 152 ± 22%. Although endothelial and smooth muscle-dependent vasodilation were both impaired in ischemic arteries compared to control arteries (Ach: 40 ± 14% vs 81 ± 11%, SNP: 43 ± 12% vs and 85 ± 11%, the responses to acetylcholine and sodium nitroprusside were similar, implicating impaired smooth muscle-dependent vasodilation. Conversely, vasoconstriction responses to norepinephrine were not different between ischemic and control arteries, -68 ± 3% versus -66 ± 3%, indicating that smooth muscle cells were functional following the ischemic insult. Finally, maximal dilation responses to acetylcholine, in vitro, were significantly impaired in the ischemic artery compared to control, 71 ± 9% versus 97 ± 2%, despite a similar generation of myogenic tone to the same intravascular pressure (80 mmHg. These data indicate that ischemia impairs feed artery vasodilation by impairing the vascular wall’s responsiveness to vasodilating stimuli. Future studies to examine the mechanistic basis for these observations or treatment strategies to improve feed artery vasodilation following ischemia could provide the foundation for an alternative therapeutic paradigm for peripheral arterial occlusive disease.

Functional effects of renal artery stent placement on treated and contralateral kidneys.

NARCIS (Netherlands)

Leertouwer, T.C.; Derkx, F.H.M.; Pattynama, P.M.; Deinum, J.; Dijk, L.C. van; Schalekamp, M.A.D.H.

2002-01-01

BACKGROUND: This study examined the effects of stent placement for renal artery stenosis on the function of treated and contralateral kidneys. METHODS: Eighteen patients who underwent stent placement for unilateral renal artery stenosis presenting with hypertension and/or renal failure were studied

Morphology and function of dog arterial grafts preserved in UW-solution

NARCIS (Netherlands)

Vischjager, M.; van Gulik, T. M.; Pfaffendorf, M.; van Zwieten, P. A.; van Marle, J.; Kromhout, J. G.; Klopper, P. J.; Jacobs, M. J.

1995-01-01

To assess the function of arterial grafts after prolonged preservation in the University of Wisconsin solution (UW), in vitro and in vivo. Carotid arteries were harvested from dogs and stored for 1-21 days at 4 degrees C in UW (n = 10) or in PBS (0.9% NaCl, pH 7.4), (PBS) (n = 10). Slices were

Effect of dark chocolate on arterial function in healthy individuals.

Science.gov (United States)

Vlachopoulos, Charalambos; Aznaouridis, Konstantinos; Alexopoulos, Nikolaos; Economou, Emmanuel; Andreadou, Ioanna; Stefanadis, Christodoulos

2005-06-01

Epidemiologic studies suggest that high flavonoid intake confers a benefit on cardiovascular outcome. Endothelial function, arterial stiffness, and wave reflections are important determinants of cardiovascular performance and are predictors of cardiovascular risk. The effect of flavonoid-rich dark chocolate (100 g) on endothelial function, aortic stiffness, wave reflections, and oxidant status were studied for 3 h in 17 young healthy volunteers according to a randomized, single-blind, sham procedure-controlled, cross-over protocol. Flow-mediated dilation (FMD) of the brachial artery, aortic augmentation index (AIx), and carotid-femoral pulse wave velocity (PWV) were used as measures of endothelial function, wave reflections, and aortic stiffness, respectively. Plasma oxidant status was evaluated with measurement of plasma malondialdehyde (MDA) and total antioxidant capacity (TAC). Chocolate led to a significant increase in resting and hyperemic brachial artery diameter throughout the study (maximum increase by 0.15 mm and 0.18 mm, respectively, P chocolate throughout the study (maximum absolute decrease 7.8%, P chocolate, indicating no alterations in plasma oxidant status. Our study shows for the first time that consumption of dark chocolate acutely decreases wave reflections, that it does not affect aortic stiffness, and that it may exert a beneficial effect on endothelial function in healthy adults. Chocolate consumption may exert a protective effect on the cardiovascular system; further studies are warranted to assess any long-term effects.

Effect of dark chocolate on arterial function in healthy individuals: cocoa instead of ambrosia?

Science.gov (United States)

Vlachopoulos, Charalambos; Alexopoulos, Nikolaos; Stefanadis, Christodoulos

2006-06-01

Cocoa has been consumed for at least 2500 years, and for long time it has been regarded as a medicine. Arterial function is of paramount importance for the proper function and integrity of the cardiovascular system. Dark chocolate and flavonoid-rich cocoa have beneficial acute and short-term effects on endothelial function and wave reflections in normal individuals, in adults with cardiovascular risk factors, and in patients with coronary artery disease. Furthermore, dark chocolate and flavonoid-rich cocoa may have a blood pressure-lowering effect. These effects can be attributed to flavonoids and are mainly mediated through increased nitric oxide bioavailability. Further research is needed to demonstrate whether these effects of chocolate on arterial function are translated into clinical benefit.

Functional assessment of sequential coronary artery fistula and coronary artery stenosis with fractional flow reserve and stress adenosine myocardial perfusion imaging

Directory of Open Access Journals (Sweden)

Kuan Leong Yew

2015-10-01

Full Text Available Coronary artery fistula is an abnormal connection between one coronary artery to another coronary artery or cardiac chambers. The coronary artery fistula may cause significant shunting of blood and cause “pseudo-stenosis” or “steal phenomenon”. This will also accentuate pre-existing mild-moderate de novo coronary lesions with resultant greater pressure gradient difference across the lesions. Thus, fractional flow reserve can be a useful tool to guide intervention decision on the coronary artery fistula. There are very few published reports regarding the use of FFR to assess coronary artery fistula. In fact, there is no outcome data regarding the deferment of coronary artery fistula intervention when the FFR is not physiologically significant. This case highlighted the use of FFR to evaluate the functional significance of coronary fistula in the setting of ischemia evaluation and it was proven to be safe to defer intervention with good 3 year clinical outcome. Stress adenosine myocardial perfusion imaging correlated with the FFR result.

Changes of heart rate variability and baroreflex sensitivity in patients soon after orthotopic heart transplantation

Czech Academy of Sciences Publication Activity Database

Fráňa, P.; Kára, T.; Souček, M.; Halámek, Josef; Řiháček, I.; Orban, O.; Toman, J.; Bartosikova, L.; Nečas, J.; Dzurova, J.

2002-01-01

Roč. 20, č. 4 (2002), s. S293 ISSN 0263-6352. [Scientific meeting of the international society of hypertension - european meeting on hypertension. 23.06.2002-27.06.2002, Praha] R&D Projects: GA ČR GA102/00/1262; GA ČR GA102/02/1339 Institutional research plan: CEZ:AV0Z2065902 Keywords : baroreflex * heart transplantation * ANS Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

Exercise training improves endothelial function in resistance arteries of young prehypertensives.

Science.gov (United States)

Beck, D T; Martin, J S; Casey, D P; Braith, R W

2014-05-01

Prehypertension is associated with reduced conduit artery endothelial function and perturbation of oxidant/antioxidant status. It is unknown whether endothelial dysfunction persists to resistance arteries and whether exercise training affects oxidant/antioxidant balance in young prehypertensives. We examined resistance artery function using venous occlusion plethysmography measurement of forearm (FBF) and calf blood flow (CBF) at rest and during reactive hyperaemia (RH), as well as lipid peroxidation (8-iso-PGF2α) and antioxidant capacity (Trolox-equivalent antioxidant capacity; TEAC) before and after exercise intervention or time control. Forty-three unmedicated prehypertensive and 15 matched normotensive time controls met screening requirements and participated in the study (age: 21.1±0.8 years). Prehypertensive subjects were randomly assigned to resistance exercise training (PHRT; n=15), endurance exercise training (PHET; n=13) or time-control groups (PHTC; n=15). Treatment groups exercised 3 days per week for 8 weeks. Peak and total FBF were lower in prehypertensives than normotensives (12.7±1.2 ml min(-1) per100 ml tissue and 89.1±7.7 ml min(-1) per 100 ml tissue vs 16.3±1.0 ml min(-1) per 100 ml tissue and 123.3±6.4 ml min(-1) per 100 ml tissue, respectively; Pendurance training are effective in improving resistance artery endothelial function and oxidant/antioxidant balance in young prehypertensives.

Adolescent vulnerability to cardiovascular consequences of chronic social stress: Immediate and long-term effects of social isolation during adolescence.

Science.gov (United States)

Cruz, Fábio C; Duarte, Josiane O; Leão, Rodrigo M; Hummel, Luiz F V; Planeta, Cleopatra S; Crestani, Carlos C

2016-01-01

It has been demonstrated that disruption of social bonds and perceived isolation (loneliness) are associated with an increased risk of cardiovascular morbidity and mortality. Adolescence is proposed as a period of vulnerability to stress. Nevertheless, the impact of chronic social stress during this ontogenic period in cardiovascular function is poorly understood. Therefore, the purpose of this study was to compare the impact in cardiovascular function of social isolation for 3 weeks in adolescent and adult male rats. Also, the long-term effects of social isolation during adolescence were investigated longitudinally. Social isolation reduced body weight in adolescent, but not in adult animals. Disruption of social bonds during adolescence increased arterial pressure without affecting heart rate and pulse pressure (PP). Nevertheless, social isolation in adulthood reduced systolic arterial pressure and increased diastolic arterial pressure, which in turn decreased PP without affecting mean arterial pressure. Cardiovascular changes in adolescents, but not adults, were followed by facilitation of both baroreflex sensitivity and vascular reactivity to the vasodilator agent acetylcholine. Vascular responsiveness to either the vasodilator agent sodium nitroprusside or the vasoconstrictor agent phenylephrine was not affected by social isolation. Except for the changes in body weight and baroreflex sensitivity, all alterations evoked by social isolation during adolescence were reversed in adulthood after moving animals from isolated to collective housing. These findings suggest a vulnerability of adolescents to the effects of chronic social isolation in cardiovascular function. However, results indicate minimal cardiovascular consequences in adulthood of disruption of social bonds during adolescence. © 2015 Wiley Periodicals, Inc.

Biomarkers of coagulation, fibrinolysis, endothelial function, and inflammation in arterialized venous blood

DEFF Research Database (Denmark)

Gram, Anne Sofie; Skov, Jane; Ploug, Thorkil

2014-01-01

Effects of venous blood arterialization on cardiovascular risk markers are still unknown. We evaluated biomarkers of inflammation, coagulation, fibrinolysis, and endothelial function in arterialized compared with regular venous blood. Cubital venipunctures were obtained from 10 healthy volunteers....... Arterialization was generated by 10 min heating of the contralateral hand. Concentrations of albumin, C-reactive protein (CRP), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), and von Willebrand factor (vWF) were measured by validated assays. Concentrations of albumin......, CRP, and vWF were significantly lower in arterialized than in venous blood (albumin: 43.8 g/l and 44.8 g/l, P = 0.02). Differences in CRP and vWF became insignificant after adjusting for albumin. The endogenous thrombin potential (ETP) was significantly higher in arterialized than in venous blood...

Appropriate control time constant in relation to characteristics of the baroreflex vascular system in 1/R control of the total artificial heart.

Science.gov (United States)

Mizuta, Sora; Saito, Itsuro; Isoyama, Takashi; Hara, Shintaro; Yurimoto, Terumi; Li, Xinyang; Murakami, Haruka; Ono, Toshiya; Mabuchi, Kunihiko; Abe, Yusuke

2017-09-01

1/R control is a physiological control method of the total artificial heart (TAH) with which long-term survival was obtained with animal experiments. However, 1/R control occasionally diverged in the undulation pump TAH (UPTAH) animal experiment. To improve the control stability of the 1/R control, appropriate control time constant in relation to characteristics of the baroreflex vascular system was investigated with frequency analysis and numerical simulation. In the frequency analysis, data of five goats in which the UPTAH was implanted were analyzed with first Fourier transform technique to examine the vasomotion frequency. The numerical simulation was carried out repeatedly changing baroreflex parameters and control time constant using the elements-expanded Windkessel model. Results of the frequency analysis showed that the 1/R control tended to diverge when very low frequency band that was an indication of the vasomotion frequency was relative high. In numerical simulation, divergence of the 1/R control could be reproduced and the boundary curves between the divergence and convergence of the 1/R control varied depending on the control time constant. These results suggested that the 1/R control tended to be unstable when the TAH recipient had high reflex speed in the baroreflex vascular system. Therefore, the control time constant should be adjusted appropriately with the individual vasomotion frequency.

The study of the value of applying the special functions of DSA during uterine artery embolization

International Nuclear Information System (INIS)

Wang Ting; Zhao Zhenhua; Lv Weigong

2007-01-01

Objective: To study the value of applying the special functions of DSA during uterine artery embolization. Methods: 122 cases were performed uterine artery embolization, including 67 cases with traditional operation and 55 cases with applying the special functions of DSA: rotary DSA angiography, the best work position and road map technology. We recorded the correlative operative indices to compare and analyse the mean exposure time, the mean operative time, the mean dosage of contrast medium, the probability of vasospasm and injury of blood vessel during operation. Results: The mean exposure time, mean operative time and the mean dosage of contrast medium were reduced with the special functions of DSA during uterine artery embolization. There is significant difference between traditional operation and the operation applying the special functions of DSA (P<0.01). Conclusion: Applying the special functions of DSA during uterine artery embolization can reduce the operative time, operative risk and economic burden. (authors)

Obesity and overweight associated with increased carotid diameter and decreased arterial function in young otherwise healthy men.

Science.gov (United States)

Kappus, Rebecca M; Fahs, Christopher A; Smith, Denise; Horn, Gavin P; Agiovlasitis, Stomatis; Rossow, Lindy; Jae, Sae Y; Heffernan, Kevin S; Fernhall, Bo

2014-04-01

Obesity is linked to cardiovascular disease, stroke, increased mortality and vascular remodeling. Although increased arterial diameter is associated with multiple cardiovascular risk factors and obesity, it is unknown whether lumen enlargement is accompanied by unfavorable vascular changes in young and otherwise healthy obese individuals. The purpose of this study was to compare carotid and brachial artery diameter, blood pressure, arterial stiffness, and endothelial function in young, apparently healthy, normal-weight, overweight, and obese male subjects. One hundred sixty-five male subjects (27.39±0.59 years) were divided into 3 groups (normal weight, overweight, and obese) according to body mass index. Subjects underwent cardiovascular measurements to determine arterial diameter, function, and stiffness. After adjusting for age, the obese group had significantly greater brachial, carotid, and aortic pressures, brachial pulse wave velocity, carotid intima media thickness, and carotid arterial diameter compared with both the overweight and normal-weight groups. Obesity is associated with a much worse arterial profile, as an increased carotid lumen size was accompanied by higher blood pressure, greater arterial stiffness, and greater carotid intima media thickness in obese compared with overweight or normal-weight individuals. These data suggest that although obesity may be a factor in arterial remodeling, such remodeling is also accompanied by other hemodynamic and arterial changes consistent with reduced arterial function and increased cardiovascular risk.

The influence of tobacco smoking on the relationship between pressure and flow in the middle cerebral artery in humans.

Science.gov (United States)

Peebles, Karen C; Horsman, Helen; Tzeng, Yu-Chieh

2013-01-01

Cigarette smoking is associated with an increased risk of stroke but the mechanism is unclear. The study examined whether acute and chronic cigarette smoking alters the dynamic relationship between blood pressure and cerebral blood flow. We hypothesised that acute and chronic smoking would result in a cerebral circulation that was less capable of buffering against dynamic fluctuations in blood pressure. Further, these changes would be accompanied by a reduction in baroreflex sensitivity, which is reduced after smoking (acute smoking). We recruited 17 non-smokers and 15 habitual smokers (13 ± 5 pack years). Continuous measurements of mean cerebral blood flow velocity (transcranial Doppler ultrasound), blood pressure (finger photoplethysmography) and heart rate enabled transfer function analysis of the dynamic relationship between pressure and flow (gain, normalised gain, phase and coherence) and baroreflex sensitivity during supine rest before and after smoking a single cigarette (acute smoking). There were no between-group differences in gain, phase or coherence before acute smoking. However, both groups showed a reduction in gain and coherence, associated with a reduction in baroreflex sensitivity, and increase in phase after acute smoking. Contrary to our hypothesis, these findings suggest that in the face of a reduction in baroreflex sensitivity acute smoking may potentially improve the ability of the cerebral circulation to buffer against changes in blood pressure. However, chronic smoking did not alter the dynamic relationship between blood pressure and cerebral blood flow velocity. These results have implications on understanding mechanisms for attenuating stroke risk.

Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

DEFF Research Database (Denmark)

Kneifel, M; Scholze, A; Burkert, A

2006-01-01

It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

Energy Technology Data Exchange (ETDEWEB)

Tolezani, Elaine Cristina; Costa-Hong, Valéria, E-mail: hong.valeria@gmail.com; Correia, Gustavo; Mansur, Alfredo José; Drager, Luciano Ferreira; Bortolotto, Luiz Aparecido [Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

2014-11-15

Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients. To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations. This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years) with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior{sup ®} device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound. The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01) and triglycerides (p = 0.02); intima-media thickness, to age (p < 0.01); diameter, to creatinine (p = 0.03) and age (p = 0.02); relative distensibility, to age (p < 0.01) and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively). Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01) and with relative distensibility (p < 0.01), while diameter showed a positive correlation with distensibility (p = 0.03). In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic blood pressure related to the carotid functional measure

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

International Nuclear Information System (INIS)

Tolezani, Elaine Cristina; Costa-Hong, Valéria; Correia, Gustavo; Mansur, Alfredo José; Drager, Luciano Ferreira; Bortolotto, Luiz Aparecido

2014-01-01

Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients. To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations. This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years) with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior ® device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound. The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01) and triglycerides (p = 0.02); intima-media thickness, to age (p < 0.01); diameter, to creatinine (p = 0.03) and age (p = 0.02); relative distensibility, to age (p < 0.01) and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively). Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01) and with relative distensibility (p < 0.01), while diameter showed a positive correlation with distensibility (p = 0.03). In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic blood pressure related to the carotid functional measure. The

Determinants of Functional and Structural Properties of Large Arteries in Healthy Individuals

Directory of Open Access Journals (Sweden)

Elaine Cristina Tolezani

2014-11-01

Full Text Available Background: Changes in the properties of large arteries correlate with higher cardiovascular risk. Recent guidelines have included the assessment of those properties to detect subclinical disease. Establishing reference values for the assessment methods as well as determinants of the arterial parameters and their correlations in healthy individuals is important to stratify patients. Objective: To assess, in healthy adults, the distribution of the values of pulse wave velocity, diameter, intima-media thickness and relative distensibility of the carotid artery, in addition to assessing the demographic and clinical determinants of those parameters and their correlations. Methods: This study evaluated 210 individuals (54% women; mean age, 44 ± 13 years with no evidence of cardiovascular disease. The carotid-femoral pulse wave velocity was measured with a Complior® device. The functional and structural properties of the carotid artery were assessed by using radiofrequency ultrasound. Results: The means of the following parameters were: pulse wave velocity, 8.7 ± 1.5 m/s; diameter, 6,707.9 ± 861.6 μm; intima-media thickness, 601 ± 131 μm; relative distensibility, 5.3 ± 2.1%. No significant difference related to sex or ethnicity was observed. On multiple linear logistic regression, the factors independently related to the vascular parameters were: pulse wave velocity, to age (p < 0.01 and triglycerides (p = 0.02; intima-media thickness, to age (p < 0.01; diameter, to creatinine (p = 0.03 and age (p = 0.02; relative distensibility, to age (p < 0.01 and systolic and diastolic blood pressures (p = 0.02 and p = 0.01, respectively. Pulse wave velocity showed a positive correlation with intima media thickness (p < 0.01 and with relative distensibility (p < 0.01, while diameter showed a positive correlation with distensibility (p = 0.03. Conclusion: In healthy individuals, age was the major factor related to aortic stiffness, while age and diastolic

Renal artery stenting in solitary functioning kidneys: Technical and clinical results

International Nuclear Information System (INIS)

Sahin, Sinan; Cimsit, Cagatay; Andac, Nurten; Baltacioglu, Feyyaz; Tuglular, Serhan; Akoglu, Emel

2006-01-01

Objective: To evaluate the clinical and technical results of renal artery stenting for the treatment of renovascular hypertension and renal failure in patients with solitary functioning kidney. Materials and methods: Fifteen patients with solitary functioning kidney underwent renal artery stenting and were followed up for 12-60 months. Before the procedures, systolic and diastolic blood pressures and serum creatinine levels were measured and the number of antihypertensive drugs was recorded and followed up after stenting. In case of restenosis, either in-stent percutaneous transluminal renal angioplasty or stent-in-stent placement was performed. Results: Primary technical success rate was 100%. One lesion was nonostial while 14 were ostial. Primary patency rates were 100% for 6 months, 92.3% for 12 months, and 69.2% for 24 months. The secondary patency rate at 24 months was 100%. The differences between the baseline and postprocedural values of systolic blood pressures, diastolic blood pressures and the number of antihypertensive drug were statistically significant (P < 0.05), except the values of serum creatinine. Hypertension was cured in 1 (6.7%) patient, improved in 4 (26.6%) and stabilized in 10 (66.7%) patients. Renal function improved in 9 (60%), stabilized in 4 (26.6%), and deteriorated in 2 (13.4%) patients. Minor complication rate was 13.4% and major complication rate was 13.4%. Conclusion: Revascularization of renal artery stenosis using stent in solitary functioning kidneys is a safe and efficient procedure with high primary technical results, low restenosis rates and acceptable complication rates. It has an improving and controlling effect on blood pressure and renal functions

Renal artery stenting in solitary functioning kidneys: Technical and clinical results

Energy Technology Data Exchange (ETDEWEB)

Sahin, Sinan [Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Hospital, Department of Radiology, Istanbul (Turkey)]. E-mail: sinan.sahin@e-kolay.net; Cimsit, Cagatay [Marmara University, School of Medicine, Department of Radiology, Istanbul (Turkey); Andac, Nurten [Marmara University, School of Medicine, Department of Radiology, Istanbul (Turkey); Baltacioglu, Feyyaz [Marmara University, School of Medicine, Department of Radiology, Istanbul (Turkey); Tuglular, Serhan [Marmara University, School of Medicine, Department of Nephrology, Istanbul (Turkey); Akoglu, Emel [Marmara University, School of Medicine, Department of Nephrology, Istanbul (Turkey)

2006-01-15

Objective: To evaluate the clinical and technical results of renal artery stenting for the treatment of renovascular hypertension and renal failure in patients with solitary functioning kidney. Materials and methods: Fifteen patients with solitary functioning kidney underwent renal artery stenting and were followed up for 12-60 months. Before the procedures, systolic and diastolic blood pressures and serum creatinine levels were measured and the number of antihypertensive drugs was recorded and followed up after stenting. In case of restenosis, either in-stent percutaneous transluminal renal angioplasty or stent-in-stent placement was performed. Results: Primary technical success rate was 100%. One lesion was nonostial while 14 were ostial. Primary patency rates were 100% for 6 months, 92.3% for 12 months, and 69.2% for 24 months. The secondary patency rate at 24 months was 100%. The differences between the baseline and postprocedural values of systolic blood pressures, diastolic blood pressures and the number of antihypertensive drug were statistically significant (P < 0.05), except the values of serum creatinine. Hypertension was cured in 1 (6.7%) patient, improved in 4 (26.6%) and stabilized in 10 (66.7%) patients. Renal function improved in 9 (60%), stabilized in 4 (26.6%), and deteriorated in 2 (13.4%) patients. Minor complication rate was 13.4% and major complication rate was 13.4%. Conclusion: Revascularization of renal artery stenosis using stent in solitary functioning kidneys is a safe and efficient procedure with high primary technical results, low restenosis rates and acceptable complication rates. It has an improving and controlling effect on blood pressure and renal functions.

Determination of baroreflex sensitivity during the modified Oxford maneuver by trigonometric regressive spectral analysis.

Directory of Open Access Journals (Sweden)

Julia Gasch

Full Text Available BACKGROUND: Differences in spontaneous and drug-induced baroreflex sensitivity (BRS have been attributed to its different operating ranges. The current study attempted to compare BRS estimates during cardiovascular steady-state and pharmacologically stimulation using an innovative algorithm for dynamic determination of baroreflex gain. METHODOLOGY/PRINCIPAL FINDINGS: Forty-five volunteers underwent the modified Oxford maneuver in supine and 60° tilted position with blood pressure and heart rate being continuously recorded. Drug-induced BRS-estimates were calculated from data obtained by bolus injections of nitroprusside and phenylephrine. Spontaneous indices were derived from data obtained during rest (stationary and under pharmacological stimulation (non-stationary using the algorithm of trigonometric regressive spectral analysis (TRS. Spontaneous and drug-induced BRS values were significantly correlated and display directionally similar changes under different situations. Using the Bland-Altman method, systematic differences between spontaneous and drug-induced estimates were found and revealed that the discrepancy can be as large as the gain itself. Fixed bias was not evident with ordinary least products regression. The correlation and agreement between the estimates increased significantly when BRS was calculated by TRS in non-stationary mode during the drug injection period. TRS-BRS significantly increased during phenylephrine and decreased under nitroprusside. CONCLUSIONS/SIGNIFICANCE: The TRS analysis provides a reliable, non-invasive assessment of human BRS not only under static steady state conditions, but also during pharmacological perturbation of the cardiovascular system.

Favorable effects of concord grape juice on endothelial function and arterial stiffness in healthy smokers.

Science.gov (United States)

Siasos, Gerasimos; Tousoulis, Dimitris; Kokkou, Eleni; Oikonomou, Evangelos; Kollia, Maria-Eleni; Verveniotis, Aleksis; Gouliopoulos, Nikolaos; Zisimos, Konstantinos; Plastiras, Aris; Maniatis, Konstantinos; Stefanadis, Christodoulos

2014-01-01

Smoking is associated with impaired vascular function. Concord grape juice (CGJ), a rich source of flavonoids, can modify cardiovascular risk factors. Endothelial function and arterial stiffness are surrogate markers of arterial health. We examined the impact of CGJ on arterial wall properties in healthy smokers. We studied the effect of a 2-week oral treatment with CGJ in 26 healthy smokers on 3 occasions (day 0 (baseline), day 7, and day 14) in a randomized, placebo-controlled, double-blind, crossover study. Measurements were taken before (pSm), immediately after (Sm0), and 20 minutes after (Sm20) cigarette smoking. Endothelial function was evaluated by flow-mediated dilation (FMD) of the brachial artery. Carotid-femoral pulse wave velocity (PWV) was measured as an index of aortic stiffness. Compared with placebo, treatment with CGJ resulted in a significant improvement in pSm values of FMD (P = 0.02) and PWV (P = 0.04). At baseline, smoking decreased FMD in both the CGJ group (P FMD on day 7 (P = 0.02) and day 14 (P < 0.001). Moreover, at baseline, smoking induced a significant elevation in PWV in both the CGJ group (P = 0.02) and the placebo group (P = 0.04). Treatment with CGJ prevented the smoking-induced elevation in PWV on day 7 (P = 0.003) and day 14 (P < 0.001). CGJ consumption improved endothelial function and vascular elastic properties of the arterial tree in healthy smokers and attenuated acute smoking-induced impairment of arterial wall properties.

Metabolic liver function measured in vivo by dynamic (18)F-FDGal PET/CT without arterial blood sampling.

Science.gov (United States)

Horsager, Jacob; Munk, Ole Lajord; Sørensen, Michael

2015-01-01

Metabolic liver function can be measured by dynamic PET/CT with the radio-labelled galactose-analogue 2-[(18)F]fluoro-2-deoxy-D-galactose ((18)F-FDGal) in terms of hepatic systemic clearance of (18)F-FDGal (K, ml blood/ml liver tissue/min). The method requires arterial blood sampling from a radial artery (arterial input function), and the aim of this study was to develop a method for extracting an image-derived, non-invasive input function from a volume of interest (VOI). Dynamic (18)F-FDGal PET/CT data from 16 subjects without liver disease (healthy subjects) and 16 patients with liver cirrhosis were included in the study. Five different input VOIs were tested: four in the abdominal aorta and one in the left ventricle of the heart. Arterial input function from manual blood sampling was available for all subjects. K*-values were calculated using time-activity curves (TACs) from each VOI as input and compared to the K-value calculated using arterial blood samples as input. Each input VOI was tested on PET data reconstructed with and without resolution modelling. All five image-derived input VOIs yielded K*-values that correlated significantly with K calculated using arterial blood samples. Furthermore, TACs from two different VOIs yielded K*-values that did not statistically deviate from K calculated using arterial blood samples. A semicircle drawn in the posterior part of the abdominal aorta was the only VOI that was successful for both healthy subjects and patients as well as for PET data reconstructed with and without resolution modelling. Metabolic liver function using (18)F-FDGal PET/CT can be measured without arterial blood samples by using input data from a semicircle VOI drawn in the posterior part of the abdominal aorta.

Hyperuricemia in Destabilization of Endothelial Function in Adolescents with Arterial Hypertension

Directory of Open Access Journals (Sweden)

N.M. Korenev

2013-08-01

Full Text Available The objective of this work was to study the correlation of uric acid level in blood serum and parameters of endothelial function and non-specific inflammation in adolescents with arterial hypertension considering their body weight. In the most of patients with arterial hypertension endothelial dysfunction was detected; endothelium-dependent vasodilation was more altered in the patients with obesity and especially in those with hyperuricemia. An increase in C-reactive protein serum level was mainly associated with obesity; a decrease in systolic-diastolic ratio — with hyperuricemia.

Sensing of Blood Pressure Increase by Transient Receptor Potential Vanilloid 1 Receptors on Baroreceptors

OpenAIRE

Sun, Hao; Li, De-Pei; Chen, Shao-Rui; Hittelman, Walter N.; Pan, Hui-Lin

2009-01-01

The arterial baroreceptor is critically involved in the autonomic regulation of homoeostasis. The transient receptor potential vanilloid 1 (TRPV1) receptor is expressed on both somatic and visceral sensory neurons. Here, we examined the TRPV1 innervation of baroreceptive pathways and its functional significance in the baroreflex. Resiniferatoxin (RTX), an ultrapotent analog of capsaicin, was used to ablate TRPV1-expressing afferent neurons and fibers in adult rats. Immunofluorescence labeling...

Coconut oil supplementation and physical exercise improves baroreflex sensitivity and oxidative stress in hypertensive rats.

Science.gov (United States)

Alves, Naiane F B; Porpino, Suênia K P; Monteiro, Matheus M O; Gomes, Enéas R M; Braga, Valdir A

2015-04-01

The hypothesis that oral supplementation with virgin coconut oil (Cocos nucifera L.) and exercise training would improve impaired baroreflex sensitivity (BRS) and reduce oxidative stress in spontaneously hypertensive rats (SHR) was tested. Adult male SHR and Wistar Kyoto rats (WKY) were divided into 5 groups: WKY + saline (n = 8); SHR + saline (n = 8); SHR + coconut oil (2 mL·day(-1), n = 8); SHR + trained (n = 8); and SHR + trained + coconut oil (n = 8). Mean arterial pressure (MAP) was recorded and BRS was tested using phenylephrine (8 μg/kg, intravenous) and sodium nitroprusside (25 μg·kg(-1), intravenous). Oxidative stress was measured using dihydroethidium in heart and aorta. SHR + saline, SHR + coconut oil, and SHR + trained group showed higher MAP compared with WKY + saline (175 ± 6, 148 ± 6, 147 ± 7 vs. 113 ± 2 mm Hg; p coconut oil, SHR + trained group, and SHR + trained + coconut oil groups presented lower MAP compared with SHR + saline group (148 ± 6, 147 ± 7, 134 ± 8 vs. 175 ± 6 mm Hg; p Coconut oil combined with exercise training improved BRS in SHR compared with SHR + saline group (-2.47 ± 0.3 vs. -1.39 ± 0.09 beats·min(-1)·mm Hg(-1); p coconut oil group presented reduced oxidative stress compared with SHR + saline in heart (622 ± 16 vs. 774 ± 31 AU, p coconut oil reduced oxidative stress in SHR compared with SHR + saline group (454 ± 33 vs. 689 ± 29 AU, p coconut oil combined with exercise training improved impaired BRS and reduced oxidative stress in SHR.

Chewing-induced hypertension in afferent baroreflex failure: a sympathetic response?

Science.gov (United States)

Fuente Mora, Cristina; Norcliffe-Kaufmann, Lucy; Palma, Jose-Alberto; Kaufmann, Horacio

2015-11-01

What is the central question of this study? Our goal was to understand the autonomic responses to eating in patients with congenital afferent baroreflex failure, by documenting changes in blood pressure and heart rate with chewing, swallowing and stomach distension. What is the main finding and its importance? Patients born with lesions in the afferent baroreceptor pathways have an exaggerated pressor response to food intake. This appears to be a sympathetically mediated response, triggered by chewing, that occurs independently of swallowing or distension of the stomach. The chewing-induced pressor response may be useful as a counter-manoeuvre to prevent orthostatic hypotension in these patients. Familial dysautonomia (FD) is a rare genetic disease with extremely labile blood pressure resulting from baroreflex deafferentation. Patients have marked surges in sympathetic activity, frequently surrounding meals. We conducted an observational study to document the autonomic responses to eating in patients with FD and to determine whether sympathetic activation was caused by chewing, swallowing or stomach distension. Blood pressure and R-R intervals were measured continuously while chewing gum (n = 15), eating (n = 20) and distending the stomach by percutaneous endoscopic gastrostomy tube feeding (n = 9). Responses were compared with those of normal control subjects (n = 10) and of patients with efferent autonomic failure (n = 10) who have chronically impaired sympathetic outflow. In patients with FD, eating was associated with a marked but transient pressor response (P Chewing gum evoked a similar increase in blood pressure that was higher in patients with FD than in control subjects (P = 0.0001), but was absent in patients with autonomic failure. In patients with FD, distending the stomach by percutaneous endoscopic gastrostomy tube feeding failed to elicit a pressor response. The results provide indirect evidence that chewing triggers sympathetic

The effects of baroreflex activation therapy on blood pressure and sympathetic function in patients with refractory hypertension: the rationale and design of the Nordic BAT study.

Science.gov (United States)

Gordin, Daniel; Fadl Elmula, Fadl Elmula M; Andersson, Bert; Gottsäter, Anders; Elf, Johan; Kahan, Thomas; Christensen, Kent Lodberg; Vikatmaa, Pirkka; Vikatmaa, Leena; Bastholm Olesen, Thomas; Groop, Per-Henrik; Olsen, Michael Hecht; Tikkanen, Ilkka

2017-10-01

To explore the effects of baroreflex activation therapy (BAT) on hypertension in patients with treatment resistant or refractory hypertension. This investigator-initiated randomized, double-blind, 1:1 parallel-design clinical trial will include 100 patients with refractory hypertension from 6 tertiary referral hypertension centers in the Nordic countries. A Barostim Neo System will be implanted and after 1 month patients will be randomized to either BAT for 16 months or continuous pharmacotherapy (BAT off) for 8 months followed by BAT for 8 months. A second randomization will take place after 16 months to BAT or BAT off for 3 months. Eligible patients have a daytime systolic ambulatory blood pressure (ABPM) of  ≥145 mm Hg, and/or a daytime diastolic ABPM of  ≥95 mm Hg after witnessed drug intake (including  ≥3 antihypertensive drugs, preferably including a diuretic). The primary end point is the reduction in 24-hour systolic ABPM by BAT at 8 months, as compared to pharmacotherapy. Secondary and tertiary endpoints are effects of BAT on home and office blood pressures, measures of indices of cardiac and vascular structure and function during follow-up, and safety. This academic initiative will increase the understanding of mechanisms and role of BAT in the refractory hypertension.

Blood pressure responses to dietary sodium: Association with autonomic cardiovascular function in normotensive adults.

Science.gov (United States)

Matthews, Evan L; Brian, Michael S; Edwards, David G; Stocker, Sean D; Wenner, Megan M; Farquhar, William B

2017-12-01

Blood pressure responses to dietary sodium vary widely person-to-person. Salt sensitive rodent models display altered autonomic function, a trait thought to contribute to poor cardiovascular health. Thus, we hypothesized that increased salt sensitivity (SS) in normotensive humans would be associated with increased muscle sympathetic nerve activity (MSNA), decreased high frequency heart rate variability (HF-HRV), and decreased baroreflex sensitivity. Healthy normotensive men and women completed 1week of high (300mmol·day -1 ) and 1week of low (20mmol·day -1 ) dietary sodium (random order) with 24h mean arterial pressure (MAP) assessed on the last day of each diet to assess SS. Participants returned to the lab under habitual sodium conditions for testing. Forty-two participants are presented in this analysis, 19 of which successful MSNA recordings were obtained (n=42: age 39±2yrs., BMI 24.3±0.5kg·(m 2 ) -1 , MAP 83±1mmHg, habitual urine sodium 93±7mmol·24h -1 ; n=19: MSNA burst frequency 20±2 bursts·min -1 ). The variables of interest were linearly regressed over the magnitude of SS. Higher SS was associated with increased MSNA (burst frequency: r=0.469, p=0.041), decreased HF-HRV (r=-0.349, p=0.046), and increased LF/HF-HRV (r=0.363, p=0.034). SS was not associated with sympathetic or cardiac baroreflex sensitivity (p>0.05). Multiple regression analysis accounting for age found that age, not SS, independently predicted HF-HRV (age adjusted no longer significant; p=0.369) and LF/HF-HRV (age adjusted p=0.273). These data suggest that age-related salt sensitivity of blood pressure in response to dietary sodium is associated with altered resting autonomic cardiovascular function. Copyright © 2017 Elsevier B.V. All rights reserved.

Flow-mediated dilation and peripheral arterial tonometry are disturbed in preeclampsia and reflect different aspects of endothelial function.

Science.gov (United States)

Mannaerts, Dominique; Faes, Ellen; Goovaerts, Inge; Stoop, Tibor; Cornette, Jerome; Gyselaers, Wilfried; Spaanderman, Marc; Van Craenenbroeck, Emeline M; Jacquemyn, Yves

2017-11-01

Endothelial function and arterial stiffness are known to be altered in preeclamptic pregnancies. Previous studies have shown conflicting results regarding the best technique for assessing vascular function in pregnancy. In this study, we made a comprehensive evaluation of in vivo vascular function [including flow-mediated dilatation (FMD), peripheral arterial tonometry (PAT), and arterial stiffness] in preeclamptic patients and compared them with normal pregnancies. In addition, we assessed the relation between vascular function and systemic inflammation. Fourteen patients with preeclampsia (PE) and 14 healthy pregnant controls were included. Endothelial function was determined by FMD and PAT and arterial stiffness by carotid-femoral pulse-wave velocity and augmentation index. Systemic inflammation was assessed using mean platelet volume (MPV) and neutrophil-lymphocyte ratio (NLR). The reactive hyperemia index, assessed using PAT, is decreased at the third trimester compared with the first trimester in a normal, uncomplicated pregnancy ( P = 0.001). Arterial stiffness is significantly higher in PE versus normal pregnancy ( P function, obtained by FMD, is deteriorated in PE versus normal pregnancy ( P = 0.015), whereas endothelial function assessment by PAT is improved in PE versus normal pregnancy ( P = 0.001). Systemic inflammation (MPV and NLR) increases during normal pregnancy. FMD and PAT are disturbed in PE. Endothelial function, assessed by FMD and PAT, shows distinct results. This may indicate that measurements with FMD and PAT reflect different aspects of endothelial function and that PAT should not be used as a substitute for FMD as a measure of endothelial function in pregnancy. Copyright © 2017 the American Physiological Society.

Feasibility study of the non-invasive estimation of the β+ arterial input function for human PET imaging

International Nuclear Information System (INIS)

Hubert, X.

2009-12-01

This work deals with the estimation of the concentration of molecules in arterial blood which are labelled with positron-emitting radioelements. This concentration is called 'β + arterial input function'. This concentration has to be estimated for a large number of pharmacokinetic analyses. Nowadays it is measured through series of arterial sampling, which is an accurate method but requiring a stringent protocol. Complications might occur during arterial blood sampling because this method is invasive (hematomas, nosocomial infections). The objective of this work is to overcome this risk through a non-invasive estimation of β + input function with an external detector and a collimator. This allows the reconstruction of blood vessels and thus the discrimination of arterial signal from signals in other tissues. Collimators in medical imaging are not adapted to estimate β + input function because their sensitivity is very low. During this work, they are replaced by coded-aperture collimators, originally developed for astronomy. New methods where coded apertures are used with statistical reconstruction algorithms are presented. Techniques for analytical ray-tracing and for the acceleration of reconstructions are proposed. A new method which decomposes reconstructions on temporal sets and on spatial sets is also developed to efficiently estimate arterial input function from series of temporal acquisitions. This work demonstrates that the trade-off between sensitivity and spatial resolution in PET can be improved thanks to coded aperture collimators and statistical reconstruction algorithm; it also provides new tools to implement such improvements. (author)

Effects of cranberry juice consumption on vascular function in patients with coronary artery disease.

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Dohadwala, Mustali M; Holbrook, Monika; Hamburg, Naomi M; Shenouda, Sherene M; Chung, William B; Titas, Megan; Kluge, Matthew A; Wang, Na; Palmisano, Joseph; Milbury, Paul E; Blumberg, Jeffrey B; Vita, Joseph A

2011-05-01

Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk. The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease. We completed an acute pilot study with no placebo (n = 15) and a chronic placebo-controlled crossover study (n = 44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease. In the chronic crossover study, subjects with coronary heart disease consumed a research preparation of double-strength cranberry juice (54% juice, 835 mg total polyphenols, and 94 mg anthocyanins) or a matched placebo beverage (480 mL/d) for 4 wk each with a 2-wk rest period between beverages. Beverage order was randomly assigned, and participants refrained from consuming other flavonoid-containing beverages during the study. Vascular function was measured before and after each beverage, with follow-up testing ≥12 h after consumption of the last beverage. Mean (±SD) carotid-femoral pulse wave velocity, a measure of central aortic stiffness, decreased after cranberry juice (8.3 ± 2.3 to 7.8 ± 2.2 m/s) in contrast with an increase after placebo (8.0 ± 2.0 to 8.4 ± 2.8 m/s) (P = 0.003). Brachial artery flow-mediated dilation, digital pulse amplitude tonometry, blood pressure, and carotid-radial pulse wave velocity did not change. In the uncontrolled pilot study, we observed improved brachial artery flow-mediated dilation (7.7 ± 2.9% to 8.7 ± 3.1%, P = 0.01) and digital pulse amplitude tonometry ratio (0.10 ± 0.12 to 0.23 ± 0.16, P = 0.001) 4 h after consumption of a single 480-mL portion of cranberry juice. Chronic cranberry juice consumption reduced carotid femoral pulse wave velocity-a clinically relevant measure of arterial stiffness. The uncontrolled pilot study suggested an acute benefit; however, no chronic effect on measures of endothelial vasodilator function was found. This trial

Obesity, arterial function and arterial structure – a systematic review and meta‐analysis

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Ne, J. Y. A.; Cai, T. Y.; Celermajer, D. S.; Caterson, I. D.; Gill, T.; Lee, C. M. Y.

2017-01-01

Summary Objective Obesity is an established risk factor for cardiovascular disease. The mechanisms by which obesity affects cardiovascular risk have not been fully elucidated. This paper reports a comprehensive systematic review and meta‐analysis on obesity and two key aspects of vascular health using gold‐standard non‐invasive measures – arterial endothelial function (brachial flow‐mediated dilatation) and subclinical atherosclerosis (carotid intima‐media thickness). Methods Electronic searches for ‘Obesity and flow‐mediated dilatation’ and ‘Obesity and intima‐media thickness’ were performed using Ovid Medline and Embase databases. A meta‐analysis was undertaken for brachial flow‐mediated dilatation and carotid intima‐media thickness to obtain pooled estimates for adults with obesity and those with healthy weight. Results Of the 5,810 articles retrieved, 19 studies on flow‐mediated dilatation and 19 studies on intima‐media thickness were included. Meta‐analysis demonstrated that obesity was associated with lower flow‐mediated dilatation (−1.92 % [95% CI −2.92, −0.92], P = 0.0002) and greater carotid intima‐media thickness (0.07 mm [95% CI 0.05, 0.08], P Obesity is associated with poorer arterial endothelial function and increased subclinical atherosclerosis, consistent with these aspects of vascular health at least partially contributing to the increased risk of cardiovascular events in adults with obesity. These estimated effect sizes will enable vascular health benefits in response to weight loss treatment to be put in greater perspective, both in the research setting and potentially also clinical practice. PMID:28702212

Evaluation of pulmonary arterial morphology and function in cyanotic congenital heart disease by MRI and cine MRI

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Hashimoto, Ikuo; Tsubata, Shinichi; Miyazaki, Ayumi; Ichida, Fukiko; Okada, Toshio; Murakami, Arata; Futatsuya, Ryuusuke; Nakajima, Kenshuu; Nakajima, Akio

1993-01-01

Pulmonary arterial anatomy was evaluated by magnetic resonance imaging (MRI), angiography and two-dimensional echocardiography in 20 patients with cyanotic heart disease associated with decreased pulmonary blood flow. Excellent correlation between MRI and angiographic estimates of pulmonary artery diameter was obtained (main pulmonary artery, r=0.87; right pulmonary artery, r=0.96; left pulmonary artery, r=0.95). However, echocardiography could not describe peripheral pulmonary arteries obviously, especially left pulmonary artery. In the assessment of peripheral pulmonary stenosis or obstruction, cine MRI was superior to echocardiography. We conclude that MRI and cine MRI will play an important role in the serial evaluation of pulmonary arterial morphology and function in patients with cyanotic congenital heart disease before and after surgical repair. (author)

Evaluation of pulmonary arterial morphology and function in cyanotic congenital heart disease by MRI and cine MRI

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Hashimoto, Ikuo; Tsubata, Shinichi; Miyazaki, Ayumi; Ichida, Fukiko; Okada, Toshio; Murakami, Arata; Futatsuya, Ryuusuke; Nakajima, Kenshuu; Nakajima, Akio [Toyama Medical and Pharmaceutical Univ. (Japan)

1993-01-01

Pulmonary arterial anatomy was evaluated by magnetic resonance imaging (MRI), angiography and two-dimensional echocardiography in 20 patients with cyanotic heart disease associated with decreased pulmonary blood flow. Excellent correlation between MRI and angiographic estimates of pulmonary artery diameter was obtained (main pulmonary artery, r=0.87; right pulmonary artery, r=0.96; left pulmonary artery, r=0.95). However, echocardiography could not describe peripheral pulmonary arteries obviously, especially left pulmonary artery. In the assessment of peripheral pulmonary stenosis or obstruction, cine MRI was superior to echocardiography. We conclude that MRI and cine MRI will play an important role in the serial evaluation of pulmonary arterial morphology and function in patients with cyanotic congenital heart disease before and after surgical repair. (author).

Autonomic modulation of arterial pressure and heart rate variability in hypertensive diabetic rats Modulação autonômica da pressão arterial e variabilidade da freqüência cardíaca em ratos hipertensos e diabéticos

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Vera de Moura Azevedo Farah

2007-01-01

Full Text Available OBJECTIVE: The aim of the present study was to evaluate the autonomic modulation of the cardiovascular system in streptozotocin (STZ-induced diabetic spontaneously hypertensive rats (SHR, evaluating baroreflex sensitivity and arterial pressure and heart rate variability. METHODS: Male SHR were divided in control (SHR and diabetic (SHR+DM, 5 days after STZ groups. Arterial pressure (AP and baroreflex sensitivity (evaluated by tachycardic and bradycardic responses to changes in AP were monitored. Autoregressive spectral estimation was performed for systolic AP (SAP and pulse interval (PI with oscillatory components quantified as low (LF:0.2-0.6Hz and high (HF:0.6-3.0Hz frequency ranges. RESULTS: Mean AP and heart rate in SHR+DM (131±3 mmHg and 276±6 bpm were lower than in SHR (160±7 mmHg and 330±8 bpm. Baroreflex bradycardia was lower in SHR+DM as compared to SHR (0.55±0.1 vs. 0.97±0.1 bpm/mmHg. Overall SAP variability in the time domain (standard deviation of beat-by-beat time series of SAP was lower in SHR+DM (3.1±0.2 mmHg than in SHR (5.7±0.6 mmHg. The standard deviation of the PI was similar between groups. Diabetes reduced the LF of SAP (3.3±0.8 vs. 28.7±7.6 mmHg2 in SHR, while HF of SAP were unchanged. The power of oscillatory components of PI did not differ between groups. CONCLUSIONS: These results show that the association of hypertension and diabetes causes an impairment of the peripheral cardiovascular sympathetic modulation that could be, at least in part, responsible for the reduction in AP levels. Moreover, this study demonstrates that diabetes might actually impair the reduced buffer function of the baroreceptors while reducing blood pressure.OBJETIVO: O objetivo do presente estudo foi investigar a modulação autonômica do sistema cardiovascular em ratos espontâneamente hipertensos (SHR e diabéticos por estreptozotocina (STZ, avaliando a sensibilidade do reflexo barorreceptor e a variabilidade da pressão arterial e da

Acute arterial occlusion - kidney

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... main artery to the kidney is called the renal artery. Reduced blood flow through the renal artery can hurt kidney function. ... need include: Duplex Doppler ultrasound exam of the renal arteries to test blood flow MRI of the kidney arteries, which can show ...

Renal sympathetic denervation in uncontrolled arterial hypertension after successful repair for aortic coarctation.

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Lurz, Philipp; Okon, Thomas; Riede, Thomas; Wagner, Robert; Schuler, Gerhard; Daehnert, Ingo; Desch, Steffen

2016-01-01

Uncontrolled arterial hypertension is a frequent problem after successful repair of CoA and has been attributed to increased central sympathetic drive as well as a blunted baroreceptor reflex. RSD is a promising therapy to reduce central sympathetic drive and improve baroreflex sensitivity. 8 patients (age: 27±6 years) with previous surgical and/or percutaneous repair of CoA, absence of any relevant restenosis (invasive gradient across the site of previous treatment 3±4 mmHg) and resistant arterial hypertension (daytime SBP≥140 mmHg on 24 hour ambulatory blood pressure measurements [ABPM] in spite of the concurrent use of 3 antihypertensive agents of different classes or intolerance to BP medications) were included. Bilateral RSD was performed using the Symplicity Flex™ catheter (Medtronic, MN, USA). RSD was successful in all patients with no procedural complications and no evidence for renal artery stenosis 6 months post procedure. From baseline to 6 month follow-up, RSD was followed by a significant reduction in average daytime systolic BP (150.4±7.8 to 143.1±8.0 mmHg; p=0.0117) as well as systolic BP throughout 24 h (146.8±7.3 vs. 140.5±7.8, p=0.04). The BP reductions observed in these patients justify engaging in a larger clinical trial on the efficacy of RSD in this specific type of secondary hypertension and bares the hope that RSD might extend the currently very limited armory against arterial hypertension in young adults with previous repair of CoA. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Effect of Physical Resistance Training on Baroreflex Sensitivity of Hypertensive Rats

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Moisés Felipe Pereira Gomes

Full Text Available Abstract Background: Baroreceptors act as regulators of blood pressure (BP; however, its sensitivity is impaired in hypertensive patients. Among the recommendations for BP reduction, exercise training has become an important adjuvant therapy in this population. However, there are many doubts about the effects of resistance exercise training in this population. Objective: To evaluate the effect of resistance exercise training on BP and baroreceptor sensitivity in spontaneously hypertensive rats (SHR. Method: Rats SHR (n = 16 and Wistar (n = 16 at 8 weeks of age, at the beginning of the experiment, were randomly divided into 4 groups: sedentary control (CS, n = 8; trained control (CT, n = 8; sedentary SHR (HS, n = 8 and trained SHR (HT, n = 8. Resistance exercise training was performed in a stairmaster-type equipment (1.1 × 0.18 m, 2 cm between the steps, 80° incline with weights attached to their tails, (5 days/week, 8 weeks. Baroreceptor reflex control of heart rate (HR was tested by loading/unloading of baroreceptors with phenylephrine and sodium nitroprusside. Results: Resistance exercise training increased the soleus muscle mass in SHR when compared to HS (HS 0.027 ± 0.002 g/mm and HT 0.056 ± 0.003 g/mm. Resistance exercise training did not alter BP. On the other hand, in relation to baroreflex sensitivity, bradycardic response was improved in the TH group when compared to HS (HS -1.3 ± 0.1 bpm/mmHg and HT -2.6 ± 0.2 bpm/mmHg although tachycardia response was not altered by resistance exercise (CS -3.3 ± 0.2 bpm/mmHg, CT -3.3 ± 0.1 bpm/mmHg, HS -1.47 ± 0.06 bpm/mmHg and HT -1.6 ± 0.1 bpm/mmHg. Conclusion: Resistance exercise training was able to promote improvements on baroreflex sensitivity of SHR rats, through the improvement of bradycardic response, despite not having reduced BP.

Relationship of carotid arterial functional and structural changes to left atrial volume in untreated hypertension.

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Jaroch, Joanna; Rzyczkowska, Barbara; Bociąga, Zbigniew; Vriz, Olga; Driussi, Caterina; Loboz-Rudnicka, Maria; Dudek, Krzysztof; Łoboz-Grudzień, Krystyna

2016-04-01

The contribution of arterial functional and structural changes to left ventricular (LV) diastolic dysfunction has been the area of recent research. There are some studies on the relationship between arterial stiffness (a.s.) and left atrial (LA) remodelling as a marker of diastolic burden. Little is known about the association of arterial structural changes and LA remodelling in hypertension (H). The aim of this study was to examine the relationship between carotid a.s. and intima-media thickness (IMT) and LA volume in subjects with H. The study included 245 previously untreated hypertensives (166 women and 79 men, mean age 53.7 ± 11.8 years). Each patient was subjected to echocardiography with measurement of LA volume, evaluation of left ventricular hypertrophy (LVH) and LV systolic/diastolic function indices, integrated assessment of carotid IMT and echo-tracking of a.s. and wave reflection parameters. Univariate regression analysis revealed significant correlations between indexed LA volume and selected clinical characteristics, echocardiographic indices of LVH and LV diastolic/systolic function and a.s./wave reflection parameters. The following parameters were identified as independent determinants of indexed LA volume on multivariate regression analysis: diastolic blood pressure (beta = -0.229, P arterial stiffness but not intima-media thickness and LA volume in patients with untreated hypertension.

Influence of carotid artery stenting on cognitive function

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Quasar Grunwald, Iris [Saarland University Clinic, Department for Diagnostic and Interventional Neuroradiology, Homburg (Germany); Department of Neuroradiology, Homburg (Germany); Papanagiotou, Panagiotis; Backens, Martin; Politi, Maria; Vedder, Verena; Zercher, K. [Saarland University Clinic, Department for Diagnostic and Interventional Neuroradiology, Homburg (Germany); Reith, Wolfgang; Supprian, Tilman; Muscalla, B.; Haass, Anton; Krick, Christoph M. [Saarland University Clinic, Clinic for Neurology, Homburg (Germany); Saarland University Clinic, Clinic for Psychiatry and Psychotherapy, Homburg (Germany)

2010-01-15

There have only been a few studies on cognitive changes in patients with carotid occlusive disease, and the results of these show major discrepancies in the extent to which treatment affects neuropsychological function. We sought to clarify these discrepancies by evaluating the effects of carotid artery stenting (CAS) on the cognitive function. Forty-one asymptomatic CAS patients were administered a test battery of neuropsychological tests measuring cognitive speed and memory function before and 3 months after the procedure. A control group was also evaluated. To test for thromboembolic lesions, diffusion-weighted imaging was used. CAS led to a significant increase in cognitive speed (p < 0.001) but did not afford any change in memory function. This was regardless of the degree or side of stenosis or patient age or gender. CAS significantly improved functions that involve cognitive speed. Earlier studies did not differentiate between speed and memory tests and thus might have missed these changes. Further studies correlating changes in brain perfusion with increase in cognitive speed are needed. (orig.)

Influence of carotid artery stenting on cognitive function

International Nuclear Information System (INIS)

Quasar Grunwald, Iris; Papanagiotou, Panagiotis; Backens, Martin; Politi, Maria; Vedder, Verena; Zercher, K.; Reith, Wolfgang; Supprian, Tilman; Muscalla, B.; Haass, Anton; Krick, Christoph M.

2010-01-01

There have only been a few studies on cognitive changes in patients with carotid occlusive disease, and the results of these show major discrepancies in the extent to which treatment affects neuropsychological function. We sought to clarify these discrepancies by evaluating the effects of carotid artery stenting (CAS) on the cognitive function. Forty-one asymptomatic CAS patients were administered a test battery of neuropsychological tests measuring cognitive speed and memory function before and 3 months after the procedure. A control group was also evaluated. To test for thromboembolic lesions, diffusion-weighted imaging was used. CAS led to a significant increase in cognitive speed (p < 0.001) but did not afford any change in memory function. This was regardless of the degree or side of stenosis or patient age or gender. CAS significantly improved functions that involve cognitive speed. Earlier studies did not differentiate between speed and memory tests and thus might have missed these changes. Further studies correlating changes in brain perfusion with increase in cognitive speed are needed. (orig.)

Effect of age on left ventricular function during exercise in patients with coronary artery disease

International Nuclear Information System (INIS)

Hakki, A.H.; DePace, N.L.; Iskandrian, A.S.

1983-01-01

The purpose of this study was to assess the effect of age on left ventricular performance during exercise in 79 patients with coronary artery disease (greater than or equal to 50% narrowing of one or more major coronary arteries). Fifty patients under the age of 60 years (group I) and 29 patients 60 years or older (group II) were studied. Radionuclide angiograms were obtained at rest and during symptom-limited upright bicycle exercise. The history of hypertension, angina or Q wave myocardial infarction was similar in both groups. Multivessel coronary artery disease was present in 30 patients (60%) in group I and in 19 patients (66%) in group II (p . not significant). There were no significant differences between the two groups in the hemodynamic variables (at rest or during exercise) of left ventricular ejection fraction, end-diastolic volume, end-systolic volume and cardiac index. Exercise tolerance was higher in group I than in group II (7.8 +/- 0.4 versus 5.7 +/- 0.4 minutes, p . 0.009), although the exercise heart rate and rate-pressure product were not significantly different between the groups. There was poor correlation between age and ejection fraction, end-diastolic volume and end-systolic volume at rest and during exercise. Abnormal left ventricular function at rest or an abnormal response to exercise was noted in 42 patients (84%) in group I and in 25 patients (86%) in group II (p . not significant). Thus, in patients with coronary artery disease, age does not influence left ventricular function at rest or response to exercise. Older patients with coronary artery disease show changes in left ventricular function similar to those in younger patients with corresponding severity of coronary artery disease

Effect of uterine arterial embolization on the ovarian function in puerpera with postpartum hemorrhage

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Yan-Xian Deng

2017-06-01

Full Text Available Objective: To observe the hemostatic effect of uterine arterial embolization in the treatment of postpartum hemorrhage and the effect on menstruation, sex hormone level, ovarian function, and pelvic floor function. Methods: A total of 45 patients with postpartum hemorrhage who were admitted in the Department of Obstetrics of our hospital from January, 2014 to June, 2016 for uterine arterial embolization were included in the study and served as the treatment group. The postoperative menstruation recovery was recorded. The hormone levels, ovarian function, and pelvic floor function before and after treatment were recorded. A total of 42 normal puerpera were served as the control group. The menstrual status of the two groups after menstruation was compared. Results: Rapid and effective hemostasis could be obtained from patients in the treatment group after treatment with hemostasis success rate of 100%. The comparison of menstruation cycle and menstruation days after treatment between the two groups was not statistically significant. The levels of E2, P, FSH, LH and PRL, ovarian function index RI and PI, pelvic floor muscle fatigue and vaginal dynamic pressure before and after 3 and 6 months had no significant difference, and there was no significant difference between the 2 groups. Conclusions: Uterine arterial embolization in the treatment of postpartum hemorrhage is effective, and has no influence on the patient's menstrual conditions, sex hormone levels, ovarian and pelvic floor functions; therefore, it is worthy of clinical application.

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

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Valentinuzzi Max E

2010-01-01

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

Mechanisms of sympathetic activation and blood pressure elevation by intermittent hypoxia.

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Prabhakar, Nanduri R; Kumar, Ganesh K

2010-11-30

Sleep disordered breathing with recurrent apneas is one of the most frequently encountered breathing disorder in adult humans and preterm infants. Recurrent apnea patients exhibit several co-morbidities including hypertension and persistent sympathetic activation. Intermittent hypoxia (IH) resulting from apneas appears to be the primary stimulus for evoking autonomic changes. The purpose of this article is to briefly review the effects of IH on chemo- and baro-reflexes and circulating vasoactive hormones and their contribution to sympathetic activation and blood pressures. Sleep apnea patients and IH-treated rodents exhibit exaggerated arterial chemo-reflex. Studies on rodent models demonstrated that IH leads to hyperactive carotid body response to hypoxia. On the other hand, baro-reflex function is attenuated in patients with sleep apnea and in IH-treated rodents. Circulating vasoactive hormone levels are elevated in sleep apnea patients and in rodent models of IH. Thus, persistent sympathetic activation and hypertension associated with sleep apneas seems to be due to a combination of altered chemo- and baro-reflexes resulting in sympathetic activation and action of elevated circulating levels of vasoactive hormones on vasculature. Copyright © 2010 Elsevier B.V. All rights reserved.

Cardiac structure and function, and ventricular-arterial interaction 11 years following a pregnancy with preeclampsia.

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Al-Nashi, Maha; Eriksson, Maria J; Östlund, Eva; Bremme, Katarina; Kahan, Thomas

2016-04-01

Preeclampsia (PE) is associated with acute left ventricular dysfunction. Whether these changes eventually resolve remains unclear. This study assessed left and right ventricular structure and function, and ventricular-arterial interaction in 15 women 11 years after a pregnancy with PE and 16 matched control subjects with a normal pregnancy. We found normal left and right ventricular dimensions, systolic function, and global left ventricular strain, with no differences between the groups. In addition, indices of diastolic function, left and right atrial size, and amino-terminal pro-brain natriuretic peptide were normal and did not differ between the groups. Women with a previous PE had impaired night/day ratios for systolic and diastolic ambulatory blood pressure. However, indices of aortic stiffness or ventricular-arterial coupling did not differ between the groups. In conclusion, we could not demonstrate remaining alterations in systolic or diastolic left or right ventricular function, or in ventricular-arterial interaction in women 11 years after PE. Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

[Influence of Sympathetic Denervation of the Renal Artery on the Level of Arterial Blood Pressure, Cerebral Blood Flow and Cognitive Function In Patients With Resistant Arterial Hypertension].

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Efimova, Y N; Lichikaki, A V; Lishmanov, B Y

2017-07-01

To study the effect of radiofrequency ablation of renal arteries on regional cerebral blood flow and cognitive function in patients with resistant arterial hypertension (AH). Transcatheter renal denervation (TRD) was performed in 17 patients with resistant AH. Examination before and after TRD included SPECT with mTc-HMPAO, 24-hours blood pressure (BP) monitoring, and comprehensive neuropsychological testing. Fifteen patients without angiographic signs of carotid atherosclerosis, coronary artery disease and AH, neurological and psychiatric disorders were investigated as control group. Compared with control group patients with AH had decreases of regional cerebral blood flow (rCBF) in right (by 13.5%, p=0.00002) and left (by 15.5%, p=0.0006) inferior frontal lobes, in right temporal brain region (by 11.5%, p=0.008); in right and left occipital lobes (by 8.2%, p=0.04). In 6 months after TRD we observed significant improvement of cognitive function, parameters of 24-hour BP monitoring, and rCBF. We also noted definite close interdependence between changes of rCBF, indices of 24-hours BP monitoring, and dynamics of cognitive function. Improvement of long-term verbal memory correlated with increases of rCBF in left superior frontal and right occipital regions while dynamics of mentation and attention correlated positively with augmentation of rCBF in right posterior parietal region. Changes of perfusion in inferior parts of left frontal lobe and in right occipital region correlated with dynamics of index of diurnal diastolic hypertension time (R2=0.64, p=0.001, and R2=0.60, p=0.03, respectively). Our results suggest, that in patients with resistant AH positive effect of TRD on levels of 24-hour mean BP as well as on indices of BP load leads to in augmentation of rCBF and improvement of cognitive function.

Effect of acute moderate exercise on induced inflammation and arterial function in older adults.

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Ranadive, Sushant Mohan; Kappus, Rebecca Marie; Cook, Marc D; Yan, Huimin; Lane, Abbi Danielle; Woods, Jeffrey A; Wilund, Kenneth R; Iwamoto, Gary; Vanar, Vishwas; Tandon, Rudhir; Fernhall, Bo

2014-04-01

Acute inflammation reduces flow-mediated vasodilatation and increases arterial stiffness in young healthy individuals. However, this response has not been studied in older adults. The aim of this study, therefore, was to evaluate the effect of acute induced systemic inflammation on endothelial function and wave reflection in older adults. Furthermore, an acute bout of moderate-intensity aerobic exercise can be anti-inflammatory. Taken together, we tested the hypothesis that acute moderate-intensity endurance exercise, immediately preceding induced inflammation, would be protective against the negative effects of acute systemic inflammation on vascular function. Fifty-nine healthy volunteers between 55 and 75 years of age were randomized to an exercise or a control group. Both groups received a vaccine (induced inflammation) and sham (saline) injection in a counterbalanced crossover design. Inflammatory markers, endothelial function (flow-mediated vasodilatation) and measures of wave reflection and arterial stiffness were evaluated at baseline and at 24 and 48 h after injections. There were no significant differences in endothelial function and arterial stiffness between the exercise and control group after induced inflammation. The groups were then analysed together, and we found significant differences in the inflammatory markers 24 and 48 h after induction of acute inflammation compared with sham injection. However, flow-mediated vasodilatation, augmentation index normalized for heart rate (AIx75) and β-stiffness did not change significantly. Our results suggest that acute inflammation induced by influenza vaccination did not affect endothelial function in older adults.

[Features of daily rhythm of arterial pressure in patients with primary arterial hypertension and neurogenic syncope conditions].

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Musaeva, Z A; Oknin, V Iu; Khapaev, B A; Fedotova, A V; Veĭn, A M

2002-01-01

A comparative analysis of parameters of systemic BP in patients with primary arterial hypotension (PAH) and in patients with neurogenic syncopes (NS) in the cycle sleep-awake. Blood pressure was investigated in 20 patients with PAH aged 16-44 years and 18 patients with NS aged 16-49 years. 24-h ambulatory monitoring of BP was made on the monitor ABPM-02/M (Meditech, Hungary). Rhythm indices of BP in NS patients corresponded to age normal criteria. 24-h arrhythmia of BP in PAH patients manifests with excessive drop of diastolic BP in sleep (55% patients were overdippers). PAH and NS patients differ maximally by hypotonic load in sleep: 1.0 +/- 0.7% in NS vs 15.4 +/- 3.2% in PAH. Hypotonia episodes in awake PAH patients were registered at each 4th-5th measurement of BP, in NS patients--at each 11th-13th. Heart rate in awake PAH patients is higher than in healthy subjects. Hypotonic load in sleep carries the highest differentially-diagnostic importance. This makes more perspective examinations of such patients in the cycle sleep-awake. The changes observed in PAH patients evidence for activation of cerebral sympathico-adrenal systems participating in baroreflex regulation.

[Echo-tracking technology for evaluating femoral artery endothelial function in patients with Grave's disease].

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Wei, Wei; Wang, Jingyuan; Zhao, Qiaoling; Yang, Jinru

2012-10-01

To assess the value of echo-tracking technology in evaluating endothelial function of the femoral artery in patients with Grave's disease. Thirty-four patients with Grave's disease patients and 30 normal adults as controls were recruited in this study. The intima-media thickness (IMT), arterial stiffness (β), pressure strain elastic modulus (Ep), arterial compliance (AC), pulse wave conducting velocity (PWVβ) and augmentation index (AI) parameters were examined using echo-tracking technology for evaluating the right femoral arterial elasticity. Compared with the control subjects, the patients with Grave's disease showed significantly increased β, Ep, and PWVβ and significantly decreased AC (P0.05). In patients with Grave's disease, β and Ep were positively correlated with FT3, FT4, TT3, TT4, and PWVβ was positively correlated with FT3 and FT4. Echo-tracking technology can provide more accurate quantitative evidences for early diagnosis of femoral artery endothelial dysfunction in patients with Grave's disease, but the influence of procedural factors on the measurement accuracy should be considered in the evaluation.

The predictive value of arterial stiffness on major adverse cardiovascular events in individuals with mildly impaired renal function

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Han J

2016-08-01

Full Text Available Jie Han,* Xiaona Wang,* Ping Ye, Ruihua Cao, Xu Yang, Wenkai Xiao, Yun Zhang, Yongyi Bai, Hongmei Wu Department of Geriatric Cardiology, Chinese PLA General Hospital, Beijing, People’s Republic of China *These authors contributed equally to this work Objectives: Despite growing evidence that arterial stiffness has important predictive value for cardiovascular disease in patients with advanced stages of chronic kidney disease, the predictive significance of arterial stiffness in individuals with mildly impaired renal function has not been established. The aim of this study was to evaluate the predictive value of arterial stiffness on cardiovascular disease in this specific population. Materials and methods: We analyzed measurements of arterial stiffness (carotid–femoral pulse-wave velocity [cf-PWV] and the incidence of major adverse cardiovascular events (MACEs in 1,499 subjects from a 4.8-year longitudinal study. Results: A multivariate Cox proportional-hazard regression analysis showed that in individuals with normal renal function (estimated glomerular filtration rate [eGFR] ≥90 mL/min/1.73 m2, the baseline cf-PWV was not associated with occurrence of MACEs (hazard ratio 1.398, 95% confidence interval 0.748–2.613; P=0.293. In individuals with mildly impaired renal function (eGFR <90 mL/min/1.73 m2, a higher baseline cf-PWV level was associated with a higher risk of MACEs (hazard ratio 2.334, 95% confidence interval 1.082–5.036; P=0.031. Conclusion: Arterial stiffness is a moderate and independent predictive factor for MACEs in individuals with mildly impaired renal function (eGFR <90 mL/min/1.73 m2. Keywords: epidemiology, arterial stiffness, impaired renal function, predictive value, MACEs

Arg16Gly and Gln27Glu β2 adrenergic polymorphisms influence cardiac autonomic modulation and baroreflex sensitivity in healthy young Brazilians

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Atala, Magda M; Goulart, Alessandra; Guerra, Grazia M; Mostarda, Cristiano; Rodrigues, Bruno; Mello, Priscila R; Casarine, Dulce E; Irigoyen, Maria-Claudia; Pereira, Alexandre C; Consolim-Colombo, Fernanda M

2015-01-01

The association between functional β2 adrenergic receptor (β2-AR) polymorphisms and cardiac autonomic modulation is still unclear. Thus, two common polymorphisms in the β2-AR gene (Gln27Glu β2 and Arg16Gly β2) were studied to determine whether they might affect tonic and reflex cardiac sympathetic activity in healthy young subjects. A total of 213 healthy young white subjects of both genders (53% female), aged 18-30 years (23.5±3.4 y), had their continuous blood pressure curves noninvasively recorded by Finometer at baseline, and other hemodynamic parameters, as cardiac autonomic modulation, baroreflex sensitivity, and allele, genotype, and diplotype frequencies calculated. Associations were made between Arg16Gly β2 and Gln27Glu β2 polymorphisms and between β2-AR diplotypes and all variables. The heart rate was significantly lower (P<0.001) in the presence of homozygous Arg/Arg alleles (60.9±1.5 bpm) than in that of Arg/Gly heterozygotes (65.9±1.0 bpm) or Gly/Gly homozygotes (66.3±1.2 bpm). Homozygous carriers of Arg16 allele had an alpha index (19.2±1.3) significantly higher (P<0.001) than that of the subjects with the Gly allele Gly/Gly (14.5±0.7) or Arg/Gly (14.6±0.7). Furthermore, the recessive Glu27Glu and the heterozygous Gln27Glu genotypes had a higher percentage of low-frequency components (LF%) than the homozygous Gln27Gln (15.1% vs. 16.0% vs. 8.2%, P=0.03, respectively). In healthy young subjects, the presence of β2-AR Arg16 allele in a recessive model was associated with higher baroreflex sensitivity, and increased parasympathetic modulation in studied individuals. PMID:25755837

Gender Differences in the Association between Lipid Profile and Sexual Function among Patients with Coronary Artery Disease

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Shervin Assari

2014-03-01

Full Text Available Background: Although several studies have been conducted on the association between lipid profile and sexual function among men with coronary artery disease, there is a paucity of knowledge about this association among women with coronary artery disease. Objectives: Our study aimed to evaluate the link between lipid profile and sexual function in men and women with coronary artery disease. Methods: One hundred and twenty patients with documented coronary artery disease were consecutively sampled from an outpatient cardiovascular clinic. The patients were assessed for lipid profile and sexual relationship using the Relation and Sexuality Scale (RSS. In addition, the Hospital Anxiety and Depression Scale (HADS was used to measure the symptoms of anxiety and depression. The characteristics of chest pain were also measured using the Rose Angina Questionnaire. The data were analyzed through linear regression analysis. Results: This study was conducted on 91 males (75.8% and 29 females (24.2%. Multivariate analysis showed that low-density lipoprotein cholesterol was correlated with sexual function (B = 0.01, P = 0.010 and total sexual relationship (B = 0.01, P = 0.050. A correlation was also observed between the level of high-density lipoprotein and sexual frequency score (B = -0.02, P = 0.040. Gender moderated these correlations. Among males, serum cholesterol (r = 0.193, P = 0.047 and low-density lipoprotein (r = 0.224, P = 0.037 were correlated to sexual function. In females, however, low-density lipoprotein was correlated to the total sexual relationship (r = 0.426, P = 0.021 and high-density lipoprotein was correlated to sexual frequency (r = -0.334, P = 0.046. Conclusions: The findings of this study showed a relationship between lipid profile and sexual relationship among both male and female patients with coronary artery disease. The link between lipid profile and sexual function of the patients with coronary artery disease is thus beyond just

Kidney transplantation improves arterial function measured by pulse wave analysis and endothelium-independent dilatation in uraemic patients despite deterioration of glucose metabolism

DEFF Research Database (Denmark)

Hornum, Mads; Clausen, Peter; Idorn, Thomas

2011-01-01

for kidney transplantation (uraemic control group, age 47 ± 11 years). Arterial function was estimated by the pulse wave velocity (PWV) of the carotid-femoral pulse wave, aortic augmentation index (AIX), flow-mediated (FMD) and nitroglycerin-induced vasodilatation (NID) of the brachial artery performed......BACKGROUND: The aim of this study is to investigate the effect of kidney transplantation on arterial function in relation to changes in glucose metabolism. METHODS: Included were 40 kidney recipients (Tx group, age 38 ± 13 years) and 40 patients without known diabetes remaining on the waiting list...... before transplantation and after 12 months. PWV recorded sequentially at the carotid and femoral artery is an estimate of arterial stiffness; AIX is an integrated index of vascular and ventricular function. FMD and NID are the dilatory capacities of the brachial artery after increased flow (endothelium...

Functional and structural changes in internal pudendal arteries underlie erectile dysfunction induced by androgen deprivation

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Rhéure Alves-Lopes

2017-01-01

Full Text Available Androgen deficiency is strongly associated with erectile dysfunction (ED. Inadequate penile arterial blood flow is one of the major causes of ED. The blood flow to the corpus cavernosum is mainly derived from the internal pudendal arteries (IPAs; however, no study has evaluated the effects of androgen deprivation on IPA′s function. We hypothesized that castration impairs IPAs reactivity and structure, contributing to ED. In our study, Wistar male rats, 8-week-old, were castrated and studied 30 days after orchiectomy. Functional and structural properties of rat IPAs were determined using wire and pressure myograph systems, respectively. Protein expression was determined by Western blot and immunohistochemistry. Plasma testosterone levels were determined using the IMMULITE 1000 Immunoassay System. Castrated rats exhibited impaired erectile function, represented by decreased intracavernosal pressure/mean arterial pressure ratio. IPAs from castrated rats exhibited decreased phenylephrine- and electrical field stimulation (EFS-induced contraction and decreased acetylcholine- and EFS-induced vasodilatation. IPAs from castrated rats exhibited decreased internal diameter, external diameter, thickness of the arterial wall, and cross-sectional area. Castration decreased nNOS and α-actin expression and increased collagen expression, p38 (Thr180/Tyr182 phosphorylation, as well as caspase 3 cleavage. In conclusion, androgen deficiency is associated with impairment of IPA reactivity and structure and increased apoptosis signaling markers. Our findings suggest that androgen deficiency-induced vascular dysfunction is an event involving hypotrophic vascular remodeling of IPAs.

[Possible effect of E-selectine on structure and function of arterial vessels in patients with metabolic syndrome].

Science.gov (United States)

Voloshyna, O O; Lyzohub, V H; Romanenko, I M

2007-01-01

Endothelial dysfunction and endothelial cells activation as it was shown in patients with ischemic heart disease play important role in atherosclerosis progression and the development of cardiovascular events. Relationship between E-selectine and functional/ structural changes of the arterial vessels in patients with metabolic syndrome was not explored. We revealed that both activation of the endothelial cells and structural/functional changes of the arterial wall mostly depend on obesity and dislipedemia and in less extent on carbohydrates metabolism disorders.

Effects of cranberry juice consumption on vascular function in patients with coronary artery disease123

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Dohadwala, Mustali M; Holbrook, Monika; Hamburg, Naomi M; Shenouda, Sherene M; Chung, William B; Titas, Megan; Kluge, Matthew A; Wang, Na; Palmisano, Joseph; Milbury, Paul E; Blumberg, Jeffrey B; Vita, Joseph A

2011-01-01

Background: Cranberry juice contains polyphenolic compounds that could improve endothelial function and reduce cardiovascular disease risk. Objective: The objective was to examine the effects of cranberry juice on vascular function in subjects with coronary artery disease. Design: We completed an acute pilot study with no placebo (n = 15) and a chronic placebo-controlled crossover study (n = 44) that examined the effects of cranberry juice on vascular function in subjects with coronary artery disease. Results: In the chronic crossover study, subjects with coronary heart disease consumed a research preparation of double-strength cranberry juice (54% juice, 835 mg total polyphenols, and 94 mg anthocyanins) or a matched placebo beverage (480 mL/d) for 4 wk each with a 2-wk rest period between beverages. Beverage order was randomly assigned, and participants refrained from consuming other flavonoid-containing beverages during the study. Vascular function was measured before and after each beverage, with follow-up testing ≥12 h after consumption of the last beverage. Mean (±SD) carotid-femoral pulse wave velocity, a measure of central aortic stiffness, decreased after cranberry juice (8.3 ± 2.3 to 7.8 ± 2.2 m/s) in contrast with an increase after placebo (8.0 ± 2.0 to 8.4 ± 2.8 m/s) (P = 0.003). Brachial artery flow-mediated dilation, digital pulse amplitude tonometry, blood pressure, and carotid-radial pulse wave velocity did not change. In the uncontrolled pilot study, we observed improved brachial artery flow-mediated dilation (7.7 ± 2.9% to 8.7 ± 3.1%, P = 0.01) and digital pulse amplitude tonometry ratio (0.10 ± 0.12 to 0.23 ± 0.16, P = 0.001) 4 h after consumption of a single 480-mL portion of cranberry juice. Conclusions: Chronic cranberry juice consumption reduced carotid femoral pulse wave velocity—a clinically relevant measure of arterial stiffness. The uncontrolled pilot study suggested an acute benefit; however, no chronic effect on measures of

Pressure drop and arterial compliance - Two arterial parameters in one measurement.

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Rotman, Oren M; Zaretsky, Uri; Shitzer, Avraham; Einav, Shmuel

2017-01-04

Coronary artery pressure-drop and distensibility (compliance) are two major, seemingly unrelated, parameters in the cardiovascular clinical setting, which are indicative of coronary arteries patency and atherosclerosis severity. While pressure drop is related to flow, and therefore serves as a functional indicator of a stenosis severity, the arterial distensibility is indicative of the arterial stiffness, and hence the arterial wall composition. In the present study, we hypothesized that local pressure drops are dependent on the arterial distensibility, and hence can provide information on both indices. The clinical significance is that a single measurement of pressure drop could potentially provide both functional and bio-mechanical metrics of lesions, and thus assist in real-time decision making prior to stenting. The goal of the current study was to set the basis for understanding this relationship, and define the accuracy and sensitivity required from the pressure measurement system. The investigation was performed using numerical fluid-structure interaction (FSI) simulations, validated experimentally using our high accuracy differential pressure measurement system. Simplified silicone mock coronary arteries with zero to intermediate size stenoses were used, and various combinations of arterial distensibility, diameter, and flow rate were simulated. Results of hyperemic flow cases were also compared to fractional flow reserve (FFR). The results indicate the potential clinical superiority of a high accuracy pressure drop-based parameter over FFR, by: (i) being more lesion-specific, (ii) the possibility to circumvent the FFR dependency on pharmacologically-induced hyperemia, and, (iii) by providing both functional and biomechanical lesion-specific information. Copyright © 2016 Elsevier Ltd. All rights reserved.

Functional and cosmetic results of fingertip replantation: anastomosing only the digital artery.

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Matsuzaki, Hironori; Yoshizu, Takae; Maki, Yutaka; Tsubokawa, Naoto

2004-10-01

In fingertip amputations, conventional stump plasty provides an almost acceptable functional result. However, replanting fingertips can preserve the nail and minimize loss of function. We investigated the functional and cosmetic results of fingertip replantation at the terminal branch of the digital artery. Outcomes were nailbed width and distal-segment length; sensory recovery; and range of motion (ROM) of thumb-interphalangeal (IP) or finger-distal interphalangeal (DIP) joints, and total active motion (TAM) of the replanted finger. Of 15 fingertips replanted after only arterial anastomosis, 13 were successful, and 12 were studied. After a median of 1.3 years, mean nailbed widths and distal-segment lengths were 95.4% and 93.0%, respectively, of the contralateral finger. Average TAM and ROM of the thumb-IP or finger-DIP joints were 92.0% and 83.0% of normal, respectively. Semmes-Weinstein results were blue (3.22 to 3.61) in 4 fingers and purple (3.84 to 4.31) in 8; the mean result from the 2-point discrimination test was 5.9 mm (range, 3 to 11 mm). Thus, amputated fingertips should be aggressively replanted.

The effect of blood inflow and B(1)-field inhomogeneity on measurement of the arterial input function in axial 3D spoiled gradient echo dynamic contrast-enhanced MRI.

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Roberts, Caleb; Little, Ross; Watson, Yvonne; Zhao, Sha; Buckley, David L; Parker, Geoff J M

2011-01-01

A major potential confound in axial 3D dynamic contrast-enhanced magnetic resonance imaging studies is the blood inflow effect; therefore, the choice of slice location for arterial input function measurement within the imaging volume must be considered carefully. The objective of this study was to use computer simulations, flow phantom, and in vivo studies to describe and understand the effect of blood inflow on the measurement of the arterial input function. All experiments were done at 1.5 T using a typical 3D dynamic contrast-enhanced magnetic resonance imaging sequence, and arterial input functions were extracted for each slice in the imaging volume. We simulated a set of arterial input functions based on the same imaging parameters and accounted for blood inflow and radiofrequency field inhomogeneities. Measured arterial input functions along the vessel length from both in vivo and the flow phantom agreed with simulated arterial input functions and show large overestimations in the arterial input function in the first 30 mm of the vessel, whereas arterial input functions measured more centrally achieve accurate contrast agent concentrations. Use of inflow-affected arterial input functions in tracer kinetic modeling shows potential errors of up to 80% in tissue microvascular parameters. These errors emphasize the importance of careful placement of the arterial input function definition location to avoid the effects of blood inflow. © 2010 Wiley-Liss, Inc.

Restoration of Failed Renal Graft Function After Successful Angioplasty of Pressure-Resistant Renal Artery Stenosis Using a Cutting Balloon: A Case Report

International Nuclear Information System (INIS)

Peregrin, J. H.; Buergelova, M.

2009-01-01

This study is the report of a 37-year-old male with a transplanted kidney from a 3.5-year-old donor: the graft had two arteries transplanted with an aortic patch to an external iliac artery. Four months after transplantation, the graft function deteriorated, together with the development of hypertension. Stenosis of both graft arteries was detected and the patient was referred for angioplasty. The angiographic result was suboptimal, nevertheless, the graft function improved and was more or less stable (serum creatinine, 160-200 μmol/l) for 4 years, along with persistently difficult-to-control hypertension. Five years after transplantation, the graft function deteriorated again and severe graft artery restenosis was detected. The restenosis did not respond to dilatation, graft function failed, hypertension decompensated, and left ventricular failure developed. The patient required dialysis. A cutting balloon angioplasty opened the artery, and kidney function was restored after a few days: the serum creatinine level dropped to 140-160 μmol/l, and the glomerular filtration rate (creatinine clearance) to 0.65 ml/min/1.73 m 2 . The graft function has now been stable for more than 2 years, however, the hypertension is still difficult to control.

Functional dilatation and medial remodeling of the renal artery in response to chronic increased blood flow.

Science.gov (United States)

Roan, Jun-Neng; Yeh, Chin-Yi; Chiu, Wen-Cheng; Lee, Chou-Hwei; Chang, Shih-Wei; Jiangshieh, Ya-Fen; Tsai, Yu-Chuan; Lam, Chen-Fuh

2011-01-01

Renal blood flow (RBF) is tightly regulated by several intrinsic pathways in maintaining optimal kidney blood supply. Using a rat model of aortocaval (AC) fistula, we investigated remodeling of the renal artery following prolonged increased blood flow. An AC fistula was created in the infrarenal aorta of anesthetized rats, and changes of blood flow in the renal artery were assessed using an ultrasonic flow probe. Morphological changes and expression of endothelial nitric oxide synthase and matrix metalloproteinase-2 in the remodeled renal artery were analyzed. Blood flow in the renal artery increased immediately after creation of AC fistula, but normal RBF was restored 8 weeks later. The renal artery dilated significantly 8 weeks after operation. Expression of endothelial nitric oxide synthase and matrix metalloproteinase-2 was upregulated shortly after blood flow increase, and returned to baseline levels after 3 weeks. Histological sections showed luminal dilatation with medial thickening and endothelial cell-to-smooth muscle cell attachments in the remodeled renal artery. Increased RBF was accommodated by functional dilatation and remodeling in the medial layer of the renal artery in order to restore normal blood flow. Our results provide important mechanistic insight into the intrinsic regulation of the renal artery in response to increased RBF. Copyright © 2011 S. Karger AG, Basel.

Correlations Between the Gradient of Contrast Density, Evaluated by Cardio CT, and Functional Significance of Coronary Artery Stenosis

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Orzan Marius

2016-06-01

Full Text Available Background: Assessment of the hemodynamic significance of a coronary artery stenosis is a challenging task, being extremely important for the establishment of indication for revascularization in atherosclerotic coronary artery stenosis. The aim of this study was to evaluate the role of a new marker reflecting the functional significance of a coronary artery stenosis, represented by the attenuation degree of contrast density along the stenosis by Coronary CT.

Neural regulation of the kidney function in rats with cisplatin induced renal failure

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Goulding, Niamh E.; Johns, Edward J.

2015-01-01

Aim: Chronic kidney disease (CKD) is often associated with a disturbed cardiovascular homeostasis. This investigation explored the role of the renal innervation in mediating deranged baroreflex control of renal sympathetic nerve activity (RSNA) and renal excretory function in cisplatin-induced renal failure. Methods: Rats were either intact or bilaterally renally denervated 4 days prior to receiving cisplatin (5 mg/kg i.p.) and entered a chronic metabolic study for 8 days. At day 8, other groups of rats were prepared for acute measurement of RSNA or renal function with either intact or denervated kidneys. Results: Following the cisplatin challenge, creatinine clearance was 50% lower while fractional sodium excretion and renal cortical and medullary TGF-β1 concentrations were 3–4 fold higher in both intact and renally denervated rats compared to control rats. In cisplatin-treated rats, the maximal gain of the high-pressure baroreflex curve was only 20% that of control rats, but following renal denervation not different from that of renally denervated control rats. Volume expansion reduced RSNA by 50% in control and in cisplatin-treated rats but only following bilateral renal denervation. The volume expansion mediated natriuresis/diuresis was absent in the cisplatin-treated rats but was normalized following renal denervation. Conclusions: Cisplatin-induced renal injury impaired renal function and caused a sympatho-excitation with blunting of high and low pressure baroreflex regulation of RSNA, which was dependent on the renal innervation. It is suggested that in man with CKD there is a dysregulation of the neural control of the kidney mediated by its sensory innervation. PMID:26175693

Growth hormone (GH) and atherosclerosis: changes in morphology and function of major arteries during GH treatment.

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Pfeifer, M; Verhovec, R; Zizek, B

1999-04-01

Patients with hypopituitarism have increased carotid artery intima-media thickness and reduced arterial distensibility. The effect of 2 years of growth hormone (GH) replacement therapy on these parameters was studied in 11 GH-deficient men (age range, 24-49 years) with hypopituitarism and compared with 12 healthy, age-matched men with no evidence of pituitary or vascular disease. Before treatment the intima-media of the common carotid arteries and the carotid bifurcations were significantly thicker in patients (P < 0.001) than in the control group. Treatment with GH normalized the intima-media thickness of the common carotid artery within 6 months and of the carotid bifurcation within 3 months. The changes in intima-media thickness of the carotid artery were negatively correlated with changes in serum levels of insulin-like growth factor I during treatment. There was a significant improvement in flow-mediated, endothelium-dependent dilation of the brachial artery at 3 months, which was sustained at 6, 18 and 24 months of GH treatment (P < 0.05). Thus, GH replacement therapy in GH-deficient men reverses early morphological and functional atherosclerotic changes in major arteries, and may reduce rates of vascular morbidity and mortality.

Intravascular ultrasound as a novel tool for the diagnosis and targeted treatment of functional popliteal artery entrapment syndrome

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Anna E. Boniakowski, MD

2017-06-01

Full Text Available Functional popliteal artery entrapment syndrome can be difficult to diagnose, as the imaging modalities presently employed are designed to detect anatomic entrapment. We describe a novel imaging technique to aid in diagnosis in this cohort. A 22-year-old cyclist presented with exercise-limiting claudication. Magnetic resonance angiography with provocative maneuvers was nondiagnostic. Digital subtraction angiography revealed long-segment occlusion of the popliteal artery with plantar flexion; however, the specific site of compression remained unclear. Intravascular ultrasound allowed specific localization of compression and further confirmed the diagnosis. Thus, we report this as an adjunctive imaging modality to definitively diagnose functional popliteal artery entrapment syndrome and to assist in operative planning.

Exercise training and artery function in humans: nonresponse and its relationship to cardiovascular risk factors.

NARCIS (Netherlands)

Green, D.J.; Eijsvogels, T.M.; Bouts, Y.M.; Maiorana, A.J.; Naylor, L.H.; Scholten, R.R.; Spaanderman, M.E.; Pugh, C.J.; Sprung, V.S.; Schreuder, T.H.; Jones, H.; Cable, T.; Hopman, M.T.E.; Thijssen, D.H.J.

2014-01-01

The objectives of our study were to examine 1) the proportion of responders and nonresponders to exercise training in terms of vascular function; 2) a priori factors related to exercise training-induced changes in conduit artery function, and 3) the contribution of traditional cardiovascular risk

Corrections of arterial input function for dynamic H215O PET to assess perfusion of pelvic tumours: arterial blood sampling versus image extraction

International Nuclear Information System (INIS)

Luedemann, L; Sreenivasa, G; Michel, R; Rosner, C; Plotkin, M; Felix, R; Wust, P; Amthauer, H

2006-01-01

Assessment of perfusion with 15 O-labelled water (H 2 15 O) requires measurement of the arterial input function (AIF). The arterial time activity curve (TAC) measured using the peripheral sampling scheme requires corrections for delay and dispersion. In this study, parametrizations with and without arterial spillover correction for fitting of the tissue curve are evaluated. Additionally, a completely noninvasive method for generation of the AIF from a dynamic positron emission tomography (PET) acquisition is applied to assess perfusion of pelvic tumours. This method uses a volume of interest (VOI) to extract the TAC from the femoral artery. The VOI TAC is corrected for spillover using a separate tissue TAC and for recovery by determining the recovery coefficient on a coregistered CT data set. The techniques were applied in five patients with pelvic tumours who underwent a total of 11 examinations. Delay and dispersion correction of the blood TAC without arterial spillover correction yielded in seven examinations solutions inconsistent with physiology. Correction of arterial spillover increased the fitting accuracy and yielded consistent results in all patients. Generation of an AIF from PET image data was investigated as an alternative to arterial blood sampling and was shown to have an intrinsic potential to determine the AIF noninvasively and reproducibly. The AIF extracted from a VOI in a dynamic PET scan was similar in shape to the blood AIF but yielded significantly higher tissue perfusion values (mean of 104.0 ± 52.0%) and lower partition coefficients (-31.6 ± 24.2%). The perfusion values and partition coefficients determined with the VOI technique have to be corrected in order to compare the results with those of studies using a blood AIF

Imaging of carotid artery disease: from luminology to function?

Energy Technology Data Exchange (ETDEWEB)

Gillard, J.H. [University Department of Radiology, Addenbrooke' s Hospital, Cambridge (United Kingdom)

2003-10-01

There have been tremendous advances in our ability to image atheromatous disease, particularly in the carotid artery, which is accessible and large enough to image. The repertoire of methodology available is growing, giving anatomical information on luminal narrowing which is approaching the level at which conventional carotid angiography will become very uncommon as CT and contrast-enhanced MR angiographic techniques become the norm. More exciting is the tentative ability to perform functional plaque imaging addressing enhancement patterns and macrophage activity using MR or positron-emission tomography techniques. These techniques, once rigorously evaluated, may, in addition to complex mathematical modelling of plaque, eventually allow us to assess true plaque risk. Time will best judge whether we will be able to move from the use of simple luminology to assessment of plaque function. (orig.)

Imaging of carotid artery disease: from luminology to function?

International Nuclear Information System (INIS)

Gillard, J.H.

2003-01-01

There have been tremendous advances in our ability to image atheromatous disease, particularly in the carotid artery, which is accessible and large enough to image. The repertoire of methodology available is growing, giving anatomical information on luminal narrowing which is approaching the level at which conventional carotid angiography will become very uncommon as CT and contrast-enhanced MR angiographic techniques become the norm. More exciting is the tentative ability to perform functional plaque imaging addressing enhancement patterns and macrophage activity using MR or positron-emission tomography techniques. These techniques, once rigorously evaluated, may, in addition to complex mathematical modelling of plaque, eventually allow us to assess true plaque risk. Time will best judge whether we will be able to move from the use of simple luminology to assessment of plaque function. (orig.)

MR velocity mapping measurement of renal artery blood flow in patients with impaired kidney function

DEFF Research Database (Denmark)

Cortsen, M; Petersen, L.J.; Stahlberg, F

1996-01-01

Renal blood flow (RBF) was measured in 9 patients with chronic impaired kidney function using MR velocity mapping and compared to PAH clearance and 99mTc-DTPA scintigraphy. An image plane suitable for flow measurement perpendicular to the renal arteries was chosen from 2-dimensional MR angiography....... MR velocity mapping was performed in both renal arteries using an ECG-triggered gradient echo pulse sequence previously validated in normal volunteers. Effective renal plasma flow was calculated from the clearance rate of PAH during constant infusion and the split of renal function was evaluated...... by 99mTc-DTPA scintigraphy. A reduction of RBF was found, and there was a significant correlation between PAH clearance multiplied by 1/(1-hematocrit) and RBF determined by MR velocity mapping. Furthermore, a significant correlation between the distribution of renal function and the percent distribution...

Left ventricular diastolic function in patients with coronary artery disease

Energy Technology Data Exchange (ETDEWEB)

Brugger, P.T.

1986-08-01

In 302 patients with confirmed coronary disease we determined the left ventricular diastolic function with the Nuclear Stethoscope by the aid of the Peak Filling Rate (PFR) and the Time to Peak Filling Rate (TPFR). Moreover we investigated the ejection fraction (EF). 201 patients had already suffered a myocardial infarction, of these 99 an anterior wall and 102 an inferior wall infarction. The remaining 101 patients had a CAD without a history of myocardial infarction. The PFR was 2.19 +- 0.65 EDV/sec in the 99 patients after anterior wall infarction and 2.62 +- 0.85 EDV/sec in the 102 patients after inferior wall infarction and 2.79 +- 0.85 EDV/sec in 101 patients with coronary artery disease without a history of myocardial infarction. For the PFR there could be found a statistically significant difference between normal patients and patients after anterior wall infarction (p < 0.0001), normal patients and patients after inferior wall infarction (p < 0.0001) and normal patients and patients with coronary artery disease (p < 0.0001). The TPFR was 180 +- 37.5 msec after anterior - and 158 +- 50.7 msec after inferior wall infarction and 156 +- 45.2 msec in the patients with CAD without previous infarction. The left ventricular diastolic function (PFR and/or TPFR) was abnormal in 88% after anterior- and in 82% after inferior wall infarction and in 69% in coronary patients without previous myocardial infarction. In comparison with this the ejection fraction was reduced in 66% in anterior- and in 61% inferior wall infarction at rest. These results indicate that the diastolic function at rest appears to be more informative for evaluation of a left ventricular dysfunction than the systolic function at rest.

Dissociation of endothelial function and arterial stiffness in nonobese women with polycystic ovary syndrome (PCOS).

Science.gov (United States)

Cussons, Andrea J; Watts, Gerald F; Stuckey, Bronwyn G A

2009-12-01

Polycystic ovary syndrome (PCOS) is associated with cardiovascular risk but it is not clear if this is independent of obesity and insulin resistance. This study therefore investigates endothelial function and arterial stiffness in nonobese, noninsulin resistant women with PCOS. This is cross-sectional case-control study. A total of 19 young women with PCOS, with body mass index (BMI) PCOS and control subjects when assessing the following clinical and biochemical variables: blood pressure, homeostasis model assessment insulin-resistance index, lipids and oestradiol. Women with PCOS had higher free androgen index scores (5.14 ± 3.47 vs. 3.25 ± 1.42, P = 0.036). The PCOS subjects had significantly lower FMD of the brachial artery compared with the controls (6.5 ± 2.9%vs. 10.5 ± 4.0%, P insulin resistance, have abnormal vascular function, but normal arterial stiffness, when compared with age and weight matched control subjects. Whether this leads to a greater risk of cardiovascular disease requires further investigation. © 2009 Blackwell Publishing Ltd.

Recovery coefficients for the quantification of the arterial input function from dynamic pet measurements: experimental and theoretical determination

International Nuclear Information System (INIS)

Brix, G.; Bellemann, M.E.; Hauser, H.; Doll, J.

2002-01-01

Aim: For kinetic modelling of dynamic PET data, the arterial input function can be determined directly from the PET scans if a large artery is visualized on the images. It was the purpose of this study to experimentally and theoretically determine recovery coefficients for cylinders as a function of the diameter and level of background activity. Methods: The measurements were performed using a phantom with seven cylinder inserts (φ = 5-46 mm). The cylinders were filled with an aqueous 68 Ga solution while the main chamber was filled with a 18 F solution in order to obtain a varying concentration ratio between the cylinders and the background due to the different isotope half lives. After iterative image reconstruction, the activity concentrations were measured in the center of the cylinders and the recovery coefficients were calculated as a function of the diameter and the background activity. Based on the imaging properties of the PET system, we also developed a model for the quantitative assessment of recovery coefficients. Results: The functional dependence of the measured recovery data from the cylinder diameter and the concentration ratio is well described by our model. For dynamic PET measurements, the recovery correction must take into account the decreasing concentration ratio between the blood vessel and the surrounding tissue. Under the realized measurement and data analysis conditions, a recovery correction is required for vessels with a diameter of up to 25 mm. Conclusions: Based on the experimentally verified model, the activity concentration in large arteries can be calculated from the measured activity concentration in the blood vessel and the background activity. The presented approach offers the possibility to determine the arterial input function for pharmacokinetic PET studies non-invasively from large arteries (especially the aorta). (orig.) [de

Arterial Stiffness and Autonomic Modulation After Free-Weight Resistance Exercises in Resistance Trained Individuals.

Science.gov (United States)

Kingsley, J Derek; Mayo, Xián; Tai, Yu Lun; Fennell, Curtis

2016-12-01

Kingsley, JD, Mayo, X, Tai, YL, and Fennell, C. Arterial stiffness and autonomic modulation after free-weight resistance exercises in resistance trained individuals. J Strength Cond Res 30(12): 3373-3380, 2016-We investigated the effects of an acute bout of free-weight, whole-body resistance exercise consisting of the squat, bench press, and deadlift on arterial stiffness and cardiac autonomic modulation in 16 (aged 23 ± 3 years; mean ± SD) resistance-trained individuals. Arterial stiffness, autonomic modulation, and baroreflex sensitivity (BRS) were assessed at rest and after 3 sets of 10 repetitions at 75% 1-repetition maximum on each exercise with 2 minutes of rest between sets and exercises. Arterial stiffness was analyzed using carotid-femoral pulse wave velocity (cf-PWV). Linear heart rate variability (log transformed [ln] absolute and normalized units [nu] of low-frequency [LF] and high-frequency [HF] power) and nonlinear heart rate complexity (Sample Entropy [SampEn], Lempel-Ziv Entropy [LZEn]) were measured to determine autonomic modulation. BRS was measured by the sequence method. A 2 × 2 repeated measures analysis of variance (ANOVA) was used to analyze time (rest, recovery) across condition (acute resistance exercise, control). There were significant increases in cf-PWV (p = 0.05), heart rate (p = 0.0001), normalized LF (LFnu; p = 0.001), and the LF/HF ratio (p = 0.0001). Interactions were also noted for ln HF (p = 0.006), HFnu (p = 0.0001), SampEn (p = 0.001), LZEn (p = 0.005), and BRS (p = 0.0001) such that they significantly decreased during recovery from the resistance exercise compared with rest and the control. There was no effect on ln total power, or ln LF. These data suggest that a bout of resistance exercise using free-weights increases arterial stiffness and reduces vagal activity and BRS in comparison with a control session. Vagal tone may not be fully recovered up to 30 minutes after a resistance exercise bout.

A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

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Vriens, Dennis; de Geus-Oei, Lioe-Fee; Oyen, Wim J G; Visser, Eric P

2009-12-01

For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible in practice; IDIFs are biased because of partial-volume effects and cannot be used when no large arterial blood pool is in the field of view. We propose a mathematic function, consisting of an initial linear rising activity concentration followed by a triexponential decay, to describe the APTAC. This function was fitted to 80 oncologic patients and verified for 40 different oncologic patients by area-under-the-curve (AUC) comparison, Patlak glucose metabolic rate (MR(glc)) estimation, and therapy response monitoring (Delta MR(glc)). The proposed function was compared with the gold standard (serial arterial sampling) and the IDIF. To determine the free parameters of the function, plasma time-activity curves based on arterial samples in 80 patients were fitted after normalization for administered activity (AA) and initial distribution volume (iDV) of (18)F-FDG. The medians of these free parameters were used for the model. In 40 other patients (20 baseline and 20 follow-up dynamic (18)F-FDG PET scans), this model was validated. The population-based curve, individually calibrated by AA and iDV (APTAC(AA/iDV)), by 1 late arterial sample (APTAC(1 sample)), and by the individual IDIF (APTAC(IDIF)), was compared with the gold standard of serial arterial sampling (APTAC(sampled)) using the AUC. Additionally, these 3 methods of APTAC determination were evaluated with Patlak MR(glc) estimation and with Delta MR(glc) for therapy effects using serial sampling as the gold standard. Excellent individual fits to the function were derived with significantly different decay constants (P AUC from APTAC(AA/iDV), APTAC(1 sample), and APTAC(IDIF) with the gold standard (APTAC(sampled)) were 0

Estimation of an image derived input function with MR-defined carotid arteries in FDG-PET human studies using a novel partial volume correction method

DEFF Research Database (Denmark)

Sari, Hasan; Erlandsson, Kjell; Law, Ian

2017-01-01

Kinetic analysis of18F-fluorodeoxyglucose positron emission tomography data requires an accurate knowledge the arterial input function. The gold standard method to measure the arterial input function requires collection of arterial blood samples and is an invasive method. Measuring an image deriv...... input function (p > 0.12 for grey matter and white matter). Hence, the presented image derived input function extraction method can be a practical alternative to noninvasively analyze dynamic18F-fluorodeoxyglucose data without the need for blood sampling....

Simultaneous determination of arterial input function of the internal carotid and middle cerebral arteries for dynamic susceptibility contrast MRI

International Nuclear Information System (INIS)

Scholdei, R.; Wenz, F.; Fuss, M.; Essig, M.; Knopp, M.V.

1999-01-01

Purpose: The determination of the arterial input function (AIF) is necessary for absolute quantification of the regional cerebral blood volume and blood flow using dynamic susceptibility contrast MRI. The suitability of different vessels (ICA-internal carotid artery, MCA-middle cerebral artery) for AIF determination was compared in this study. Methods: A standard 1.5 T MR system and a simultaneous dual FLASH sequence (TR/TE1/TE2/α=32/15/25/10 ) were used to follow a bolus of contrast agent. Slice I was chosen to cut the ICA perpendicularly. Slice II included the MCA. Seventeen data sets from ten subjects were evaluated. Results: The number of AIF-relevant pixels, the area under the AIF and the maximum concentration were all lower when the AIF was determined from the MCA compared to the ICA. Additionally, the mean transit time (MTT) and the time to maximum concentration (TTM) were longer in the MCA, complicating the computerized identification of AIF-relevant pixels. Data from one subject, who was examined five times, demonstrated that the intraindividual variance of the measured parameters was markedly lower than the interpersonal variance. Conclusions: It appears to be advantageous to measure the AIF in the ICA rather than the MCA. (orig.) [de

βENaC is a molecular component of a VSMC mechanotransducer that contributes to renal blood flow regulation, protection from renal injury, and hypertension.

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Drummond, Heather A

2012-01-01

Pressure-induced constriction (also known as the "myogenic response") is an important mechano-dependent response in certain blood vessels. The response is mediated by vascular smooth muscle cells (VSMCs) and characterized by a pressure-induced vasoconstriction in small arteries and arterioles in the cerebral, mesenteric, cardiac, and renal beds. The myogenic response has two important roles; it is a mechanism of blood flow autoregulation and provides protection against systemic blood pressure-induced damage to delicate microvessels. However, the molecular mechanism(s) underlying initiation of myogenic response is unclear. Degenerin proteins have a strong evolutionary link to mechanotransduction in the nematode. Our laboratory has addressed the hypothesis that these proteins may also act as mechanosensors in certain mammalian tissues such as VSMCs and arterial baroreceptor neurons. This article discusses the importance of a specific degenerin protein, β Epithelial Na(+) Channel (βENaC) in pressure-induced vasoconstriction in renal vessels and arterial baroreflex function as determined in a mouse model of reduced βENaC (βENaC m/m). We propose that loss of baroreflex sensitivity (due to loss of baroreceptor βENaC) increases blood pressure variability, increasing the likelihood and magnitude of upward swings in systemic pressure. Furthermore, loss of the myogenic constrictor response (due to loss of VSMC βENaC) will permit those pressure swings to be transmitted to the microvasculature in βENaC m/m mice, thus increasing the susceptibility to renal injury and hypertension.

Cardiovascular, cerebrovascular, and respiratory changes induced by different types of music in musicians and non-musicians: the importance of silence.

Science.gov (United States)

Bernardi, L; Porta, C; Sleight, P

2006-04-01

To assess the potential clinical use, particularly in modulating stress, of changes in the cardiovascular and respiratory systems induced by music, specifically tempo, rhythm, melodic structure, pause, individual preference, habituation, order effect of presentation, and previous musical training. Measurement of cardiovascular and respiratory variables while patients listened to music. University research laboratory for the study of cardiorespiratory autonomic function. 12 practising musicians and 12 age matched controls. After a five minute baseline, presentation in random order of six different music styles (first for a two minute, then for a four minute track), with a randomly inserted two minute pause, in either sequence. Breathing rate, ventilation, carbon dioxide, RR interval, blood pressure, mid-cerebral artery flow velocity, and baroreflex. Ventilation, blood pressure, and heart rate increased and mid-cerebral artery flow velocity and baroreflex decreased with faster tempi and simpler rhythmic structures compared with baseline. No habituation effect was seen. The pause reduced heart rate, blood pressure, and minute ventilation, even below baseline. An order effect independent of style was evident for mid-cerebral artery flow velocity, indicating a progressive reduction with exposure to music, independent of style. Musicians had greater respiratory sensitivity to the music tempo than did non-musicians. Music induces an arousal effect, predominantly related to the tempo. Slow or meditative music can induce a relaxing effect; relaxation is particularly evident during a pause. Music, especially in trained subjects, may first concentrate attention during faster rhythms, then induce relaxation during pauses or slower rhythms.

Beta-1-Selective Beta-Blockers and Cognitive Functions in Patients With Coronary Artery Disease: A Cross-Sectional Study.

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Burkauskas, Julius; Noreikaite, Aurelija; Bunevicius, Adomas; Brozaitiene, Julija; Neverauskas, Julius; Mickuviene, Narseta; Bunevicius, Robertas

2016-01-01

The association between current beta-1-selective beta-blocker use and cognitive function was evaluated in 722 patients with coronary artery disease without dementia. Beta-1-selective beta-blocker use was associated with worse incidental learning independently of sociodemographic characteristics, clinical coronary artery disease severity, and depression/anxiety.

Randomised Trial of CPAP and Vardenafil on Erectile and Arterial Function in Men with Obstructive Sleep Apnea and Erectile Dysfunction.

Science.gov (United States)

Melehan, Kerri L; Hoyos, Camilla M; Hamilton, Garun S; Wong, Keith K; Yee, Brendon J; McLachlan, Rob I; O'Meagher, Shamus; Celermajer, David; Ng, Martin K; Grunstein, Ronald R; Liu, Peter Y

2018-02-01

Erectile function is important for life satisfaction and is often impaired in men with obstructive sleep apnea (OSA). Uncontrolled studies show that treating OSA with continuous positive airway pressure (CPAP) improves erectile function. Phosphodiesterase type 5 inhibitors (e.g. vardenafil) are the first-line therapy for erectile dysfunction (ED), but may worsen OSA. To assess the effects of CPAP and vardenafil on ED. Sixty one men with moderate-to-severe OSA and ED were randomised to 12 weeks of CPAP or sham CPAP, and 10mg daily vardenafil or placebo, in a 2x2 factorial design. International Index of Erectile Function (primary endpoint), treatment and relationship satisfaction, sleep related erections, sexual function, endothelial function, arterial stiffness, quality of life, and sleep-disordered breathing. CPAP increased the frequency of sleep-related-erections, overall sexual satisfaction, and arterial stiffness but did not change erectile function or treatment satisfaction or relationship satisfaction. Vardenafil did not alter erectile function, endothelial function, arterial stiffness or sleep disordered breathing, but did improve overall self-esteem and relationship satisfaction, other aspects of sexual function and treatment satisfaction. Adherent CPAP improved erectile function, sexual desire, overall sexual, self-esteem and relationship, and treatment satisfaction, as well as sleepiness, and quality of life. Adherent vardenafil use did not consistently change nocturnal erection quality. CPAP improves overall sexual satisfaction, sleep related erections, and arterial stiffness. Low dose daily vardenafil improves certain aspects of sexual function, and did not worsen OSA. Adherent CPAP or vardenafil use further improves ED and quality of life. Copyright © 2018 Endocrine Society

Dynamic Contrast-Enhanced Perfusion MRI of High Grade Brain Gliomas Obtained with Arterial or Venous Waveform Input Function.

Science.gov (United States)

Filice, Silvano; Crisi, Girolamo

2016-01-01

The aim of this study was to evaluate the differences in dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) perfusion estimates of high-grade brain gliomas (HGG) due to the use of an input function (IF) obtained respectively from arterial (AIF) and venous (VIF) approaches by two different commercially available software applications. This prospective study includes 20 patients with pathologically confirmed diagnosis of high-grade gliomas. The data source was processed by using two DCE dedicated commercial packages, both based on the extended Toft model, but the first customized to obtain input function from arterial measurement and the second from sagittal sinus sampling. The quantitative parametric perfusion maps estimated from the two software packages were compared by means of a region of interest (ROI) analysis. The resulting input functions from venous and arterial data were also compared. No significant difference has been found between the perfusion parameters obtained with the two different software packages (P-value < .05). The comparison of the VIFs and AIFs obtained by the two packages showed no statistical differences. Direct comparison of DCE-MRI measurements with IF generated by means of arterial or venous waveform led to no statistical difference in quantitative metrics for evaluating HGG. However, additional research involving DCE-MRI acquisition protocols and post-processing would be beneficial to further substantiate the effectiveness of venous approach as the IF method compared with arterial-based IF measurement. Copyright © 2015 by the American Society of Neuroimaging.

Surgical neuroangiography. Vol. 1: Functional anatomy of craniofacial arteries

International Nuclear Information System (INIS)

Lasjaunias, P.; Berenstein, A.

1987-01-01

The contents of this book are: Arterial Anatomy: Introduction. - The Internal Maxillary System. - The Pharyngo-occipital System. - The Upper Cervical Vertebral Column: The Cervical Arteries. - The Musculocutaneous Elements of the Head and Mouth. - Thyrolaryngeal Arteries. - The Transosseous Peripheral Nervous System Arterial Supply. - Dangerous Vessels. - Collateral Circulation. - The Pharyngoocipital Collateral Pattern. - The Internal Maxillary Collateral Pattern. - The Linguofacial Collateral Pattern. - Multiple Constraints and Chronology of the Collateral Response. - Angiographic Protocols. - Angiographic Protocol of the Parasellar Region. - Angiographic Protocol of the Posterior Base of the Skull. - Angiographic Protocol of the Carotid Region. - Angiographic Protocol of the Nasomaxillaary Region. - Angiographic Protocol of the Maxillomandibular Region. - Angiographic Protocol of the Temporofacial and Scalp Region. - Angiographic Protocol of the Thyrolaryngeal Region. - References. - Subject Index

Determination of bilateral symmetry of carotid artery structure and function in children and adolescents

Directory of Open Access Journals (Sweden)

Uithoven KE

2017-01-01

Full Text Available Katelyn E Uithoven,1 Justin R Ryder,2 Roland Z Brown,3 Kyle D Rudser,3 Nicholas G Evanoff,1 Donald R Dengel,1,2 Aaron S Kelly2,4 1School of Kinesiology, University of Minnesota, 2Department of Pediatrics, University of Minnesota Medical School, 3Division of Biostatistics, School of Public Health, University of Minnesota, 4Department of Medicine, University of Minnesota Medical School, Minneapolis, MN, USA Abstract: The carotid artery represents an ideal location for noninvasive assessment of subclinical atherosclerosis in youth. Examination of arterial structure and function is generally conducted in the left common carotid. However, if the left common carotid is inaccessible or provides a poor acoustic window, it is unknown if the right common carotid can provide comparable values. The symmetry of carotid arteries in youth with high-resolution ultrasound was compared. Participants (N=230 [121 females], 13.8±2.9 years old were assessed for carotid intima media thickness (cIMT, carotid lumen diameter (cLD, carotid incremental elastic modulus (cIEM, carotid diameter compliance (cDC, carotid cross-sectional compliance (cCSC, carotid diameter distensibility (cDD, and carotid cross-sectional distensibility (cCSD. No significant differences (P>0.05 all were found for cIMT (0.49±0.09 vs 0.49±0.08 mm, cIEM (1095±382 vs 1116±346 mmHg, cDC (0.01±0.0 vs 0.01±0.0 mm/mmHg, cCSC (0.01±0.001/mmHg vs 0.01±0.001/mmHg, cDD (14.0%±3.16% vs 13.7%±3.18%, and cCSD (30.1%±7.37% vs 29.4%±7.36%. Significant differences were found for cLD (6.06±0.62 mm vs 6.33±0.64 mm, P<0.001. The majority of measures for arterial structure and function are comparable between the left and right common carotid arteries. There were differences present for cLD; however, these discrepancies are likely due to anatomical differences between the left and right common carotid arteries. Therefore, if the left common carotid is unable to be assessed properly, the right common

Use of wave intensity analysis of carotid arteries in identifying and monitoring left ventricular systolic function dynamics in rabbits.

Science.gov (United States)

Zhang, Hui; Zheng, Rongqin; Qian, Xiaoxian; Zhang, Chengxi; Hao, Baoshun; Huang, Zeping; Wu, Tao

2014-03-01

Wave intensity analysis (WIA) of the carotid artery was conducted to determine the changes that occur in left ventricular systolic function after administration of doxorubicin in rabbits. Each randomly selected rabbit was subject to routine ultrasound, WIA of the carotid artery, cardiac catheterization and pathologic examination every week and was followed for 16 wk. The first positive peak (WI1) of the carotid artery revealed that left ventricular systolic dysfunction occurred earlier than conventional indexes of heart function. WI1 was highly, positively correlated with the maximum rate of rise in left ventricular pressure in cardiac catheterization (r = 0.94, p function, and the result is highly consistent with cardiac catheterization findings and the apoptosis index of myocardial cells. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Modification of sympathetic neuronal function in the rat tail artery by dietary lipid treatment

International Nuclear Information System (INIS)

Panek, R.L.; Dixon, W.R.; Rutledge, C.O.

1985-01-01

The effect of dietary lipid treatment on sympathetic neuronal function was examined in isolated perfused tail arteries of adult rats. The hypothesis that dietary manipulations alter the lipid environment of receptor proteins which may result in the perturbation of specific membrane-associated processes that regulate peripheral adrenergic neurotransmission in the vasculature was the basis for this investigation. In the present study, rats were fed semisynthetic diets enriched in either 16% coconut oil (saturated fat) or 16% sunflower oil (unsaturated fat). The field stimulation-evoked release of endogenous norepinephrine and total 3 H was decreased significantly in rats receiving the coconut oil diet when compared to either sunflower oil- or standard lab chow-fed rats. Norepinephrine content in artery segments from coconut oil-treated rats was significantly higher compared to either sunflower oil- or standard lab chow-fed rats. Tail arteries from rats receiving the coconut oil diet displayed significantly lower perfusion pressure responses to nerve stimulation at all frequencies tested when compared to the sunflower oil- or standard lab chow-fed rats. Vasoconstrictor responses of perfused tail arteries exposed to exogenous norepinephrine resulted in an EC50 for norepinephrine that was not changed by the dietary treatment, but adult rats receiving the sunflower oil diet displayed a significantly greater maximum response to exogenous norepinephrine (10(-5) M) compared to arteries from either coconut oil- or standard lab chow-fed rats

Autonomic and Renal Alterations in the Offspring of Sleep-Restricted Mothers During Late Pregnancy

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Joyce R.S. Raimundo

Full Text Available OBJECTIVES: Considering that changes in the maternal environment may result in changes in progeny, the aim of this study was to investigate the influence of sleep restriction during the last week of pregnancy on renal function and autonomic responses in male descendants at an adult age. METHODS: After confirmation of pregnancy, female Wistar rats were randomly assigned to either a control or a sleep restriction group. The sleep-restricted rats were subjected to sleep restriction using the multiple platforms method for over 20 hours per day between the 14th and 20th day of pregnancy. After delivery, the litters were limited to 6 offspring that were designated as offspring from control and offspring from sleep-restricted mothers. Indirect measurements of systolic blood pressure (BPi, renal plasma flow, glomerular filtration rate, glomerular area and number of glomeruli per field were evaluated at three months of age. Direct measurements of cardiovascular function (heart rate and mean arterial pressure, cardiac sympathetic tone, cardiac parasympathetic tone, and baroreflex sensitivity were evaluated at four months of age. RESULTS: The sleep-restricted offspring presented increases in BPi, glomerular filtration rate and glomerular area compared with the control offspring. The sleep-restricted offspring also showed higher basal heart rate, increased mean arterial pressure, increased sympathetic cardiac tone, decreased parasympathetic cardiac tone and reduced baroreflex sensitivity. CONCLUSIONS: Our data suggest that reductions in sleep during the last week of pregnancy lead to alterations in cardiovascular autonomic regulation and renal morpho-functional changes in offspring, triggering increases in blood pressure.

Interventional treatment of arterial complications in post renal transplantation

International Nuclear Information System (INIS)

Qian Xiaojun; Dai Dingke; Zhai Renyou

2004-01-01

Objective: To report our experience of interventional procedure for arterial complications in post renal transplantation and to evaluate its clinical value. Methods: In a retrospective analysis of renal transplantations in our center, 52 cases of renal allograft artery abnormalities had taken angiography. Interventional procedure included transluminal angioplasty of arterial stenoses, treatment of arterial occlusion, and embolization of pseudoaneurysm. Results: Renal allograft artery abnormalities included artery stenosis (n=21), artery thrombosis (n=13) and embolision (n=1), renal artery pseudoaneurysms (n=2), and decrease of renal artery flow (n=3). Of the 21 artery stenosis, 2 grafts with artery stenosis were lost because the stenosis could not be corrected, and 3 with mild stenosis received no treatment. Another 16 accepted renal artery angioplasty (balloon dilation, n=12, and stent implantation, n=4). 14 achieved long-term allograft function. 1 graft was lost because renal function failed to recover. Restenosis occurred in one stent implantation, and lost the allograft function after secondary dilation. 13 cases received thrombolytic therapy through artery catheter for thrombosis and 9 achieved long-term allograft function. Thrombolyses failed in 3 cases, and renal function failed to recover in 1 case. One pseudoaneurysm received stent implantation after embolization, and got a short-term allograft function. The other one received allograft excision. Conclusion: Intravascular interventional therapy will be the first-line therapy for any indications of complication in post renal transplantation, and it can surely save the kidney in a majority of instances. (authors)

Ambulatory arterial stiffness index in chronic kidney disease stage 2-5. Reproducibility and relationship with pulse wave parameters and kidney function

DEFF Research Database (Denmark)

Boesby, Lene; Thijs, Lutgarde; Elung-Jensen, Thomas

2012-01-01

Arterial stiffness contributes to the increased cardiovascular risk in patients with chronic kidney disease (CKD). Reproducible and easily obtainable indices of arterial stiffness are needed in order to monitor therapeutic strategies. The ambulatory arterial stiffness index (AASI) has been propos...... as such a marker. The present study investigated the day-to-day reproducibility of AASI in CKD stage 2-5 and its relationship with other markers of arterial stiffness as well as with kidney function....

[Twenty-four hour time and frequency domain variability of systolic blood pressure and heart rate in an experimental model of arterial hypertension plus obesity].

Science.gov (United States)

Pelat, M; Verwaerde, P; Lazartiques, E; Cabrol, P; Galitzky, J; Berlan, M; Montastruc, J L; Senard, J M

1998-08-01

Modifications of heart rate (HR) and systolic blood pressure (SBP) variabilities (V) have been reported in the human syndrome arterial hypertension plus insulin-resistance. The aim of this study was to characterize the 24 h SBPV and HRV in both time and frequency domains during weight increase in dogs fed ad libitum with a high fat diet. Implantable transmitter units for measurement of blood pressure and heart rate were surgically implanted in five beagle male dogs. BP and HR were continuously recorded using telemetric measurements during 24 hours, before and after 6 and 9 weeks of hypercaloric diet in quiet animals submitted to a 12h light-dark cycle. To study nychtemeral cycle of SBP and HR, two periods were chosen: day (from 6.00 h to 19.00 h) and night (from 23.00 h to 6.00 h). Spontaneous baroreflex efficiency was measured using the sequence method. Spectral variability of HR and SBP was analyzed using a fast Fourier transformation on 512 consecutive values and normalized units of low (LF: 50-150 mHz, reflecting sympathetic activity) and high (HF: respiratory rate +/- 50 mHz, reflecting parasympathetic activity) frequency bands were calculated. The energy of total spectrum (from 0.004 to 1 Hz) was also studied. Body weight (12.4 +/- 0.9 vs 14.9 +/- 0.9 kg, p vs 147 +/- 1 mmHg, p vs night: 71 +/- 1 bpm) but not after 9 weeks (day: 91 +/- 4 bpm ; night: 86 +/- 2 bpm). Concomitantly, the efficiency of spontaneous baroreflex decreased at 6 weeks (36 +/- 1 vs 42 +/- 2 mmHg/ms, p energy of HRV was found after 6 but not after 9 weeks. LF energy of SBPV was increased at 6 but not at 9 weeks (table). [table: see text] In conclusion, this study shows that an hyperlipidic and hypercaloric diet induces transient variations in autonomic nervous system activity which could be the physiopathological link between obesity, insulin-resistance and arterial hypertension.

Arterial And Ventricular Elastance And Ventriculo-arterial Coupling In Asthmatic Children

International Nuclear Information System (INIS)

Ozkan, E. A.; Gecit, A.; Beysel, P.

2016-01-01

Objective: To compare arterial and ventricular end-systolic elastance and ventriculo-arterial coupling between asthma and healthy children and correlate these all three parameters with pulmonary function tests in subjects with asthma. Study Design: Across-sectional analytical study. Place and Duration of Study: Department of Pediatrics, Bozok University Medical Faculty,Yozgat, Turkey, from January 2012 to November 2014. Methodology: Transthoracic and Doppler echocardiography and pulmonary function tests in patients with asthma aged 7 - 12 years and control subjects. Forty stable asthma patients on prophylactic inhaled corticosteroids and 97 healthy subjects were investigated. Both groups were matched for age, gender, blood pressure, heart rate, body surface area, echocardiographic parameters and pulmonary function tests. Results: There was no difference regarding left ventricular elastance at end-systole derived by single beat/body surface area (Ees(sb)/BSA) between asthmatic patients and healthy children (2.59 ±1.29 mmHg/ml/m2, 2.43 ±1.28 mmHg/ml/m2 respectively, p=0.504), arterial elastance/BSA(Ea/BSA) (2.10 ±0.97, 1.75 ±0.89 respectively, p=0.041), and ventriculoarterial coupling (VAC) (0.83 ±0.13, 0.74 ±0.13, respectively, p < 0.001) were higher in asthmatic group than controls. There was no correlation between Ea, Ees (sb), VAC and pulmonary function tests. Conclusion: Arterial elastance increase and stiffness decrease in asthmatic patients. This may be due to using prophylactic inhaled corticosteroids. Using inhaled corticosteroids have protective effects against atherosclerosis. As a result of this higher arterial elastance, asthmatic children had higher VAC resulting in less efficient cardiovascular function. (author)

Could infarct location predict the long-term functional outcome in childhood arterial ischemic stroke?

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Mauricio López-Espejo

Full Text Available ABSTRACT Objective: To explore the influence of infarct location on long-term functional outcome following a first-ever arterial ischemic stroke (AIS in non-neonate children. Method: The MRIs of 39 children with AIS (median age 5.38 years; 36% girls; mean follow-up time 5.87 years were prospectively evaluated. Infarct location was classified as the absence or presence of subcortical involvement. Functional outcome was measured using the modified Rankin scale (mRS for children after the follow-up assessment. We utilized multivariate logistic regression models to estimate the odds ratios (ORs for the outcome while adjusting for age, sex, infarct size and middle cerebral artery territory involvement (significance < 0.05. Results: Both infarcts ≥ 4% of total brain volume (OR 9.92; CI 1.76 – 55.9; p 0.009 and the presence of subcortical involvement (OR 8.36; CI 1.76 – 53.6; p 0.025 independently increased the risk of marked functional impairment (mRS 3 to 5. Conclusion: Infarct extension and location can help predict the extent of disability after childhood AIS.

A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

NARCIS (Netherlands)

Vriens, D.; Geus-Oei, L.F. de; Oyen, W.J.G.; Visser, E.P.

2009-01-01

For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible

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

DEFF Research Database (Denmark)

Snoer, Martin; Olsen, Rasmus Huan; Monk-Hansen, Tea

2014-01-01

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....... 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...

Functional end-arterial circulation of the choroid assessed by using fat embolism and electric circuit simulation.

Science.gov (United States)

Lee, Ji Eun; Ahn, Ki Su; Park, Keun Heung; Pak, Kang Yeun; Kim, Hak Jin; Byon, Ik Soo; Park, Sung Who

2017-05-30

The discrepancy in the choroidal circulation between anatomy and function has remained unsolved for several decades. Postmortem cast studies revealed extensive anastomotic channels, but angiographic studies indicated end-arterial circulation. We carried out experimental fat embolism in cats and electric circuit simulation. Perfusion defects were observed in two categories. In the scatter perfusion defects suggesting an embolism at the terminal arterioles, fluorescein dye filled the non-perfused lobule slowly from the adjacent perfused lobule. In the segmental perfusion defects suggesting occlusion of the posterior ciliary arteries, the hypofluorescent segment became perfused by spontaneous resolution of the embolism without subsequent smaller infarction. The angiographic findings could be simulated with an electric circuit. Although electric currents flowed to the disconnected lobule, the level was very low compared with that of the connected ones. The choroid appeared to be composed of multiple sectors with no anastomosis to other sectors, but to have its own anastomotic arterioles in each sector. Blood flows through the continuous choriocapillaris bed in an end-arterial nature functionally to follow a pressure gradient due to the drainage through the collector venule.

CARDIAC TRANSPLANT REJECTION AND NON-INVASIVE COMON CAROTID ARTERY WALL FUNCTIONAL INDICES

Directory of Open Access Journals (Sweden)

A. O. Shevchenko

2015-01-01

Full Text Available Allograft rejection would entail an increase in certain blood biomarkers and active substances derived from activated inflammatory cells which could influence entire vascular endothelial function and deteriorate arterial wall stiffness. We propose that carotid wall functional indices measured with non-invasive ultrasound could we valuable markers of the subclinical cardiac allograft rejection. Aim. Our goal was to analyze the clinical utility of functional common carotid wall (CCW variables measured with high-resolution Doppler ultrasound as a non-invasive screening tool for allograft rejection in cardiac transplant patients (pts. Methods. One hundred and seventy one pts included 93 cardiac recipients, 30 dilated cardiomyopathy waiting list pts, and 48 stable coronary artery disease (SCAD pts without decompensated heart failure were included. Along with resistive index (Ri, pulsative index (Pi, and CCW intima-media thickness (IMT, CCW rigidity index (iRIG was estimated using empirical equation. Non-invasive evaluation was performed in cardiac transplant recipients prior the endomyo- cardial biopsy. Results. Neither of Ri, Pi, or CCW IMT were different in studied subgroups. iRIG was signifi- cantly lower in SCAD pts when compared to the dilated cardiomyopathy subgroup. The later had similar values with cardiac transplant recipients without rejection. Antibody-mediated and cellular rejection were found in 22 (23.7% and 17 (18.3% cardiac recipients, respectively. Mean iRIG in pts without rejection was significantly lower in comparison to antibody-mediated rejection and cell-mediated (5514.7 ± 2404.0 vs 11856.1 ± 6643.5 and 16071.9 ± 10029.1 cm/sec2, respectively, p = 0.001. Area under ROC for iRIG was 0.90 ± 0.03 units2. Analysis showed that iRIG values above estimated treshold 7172 cm/sec2 suggested relative risk of any type of rejection 17.7 (95%CI = 6.3–49.9 sensitivity 80.5%, specificity – 81.1%, negative predictive value – 84

[Analysis of variability of cardiac rhythm and sexual function in men with arterial hypertension during therapy with biosporolol and nebivolol].

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Nurmamedova, G S; Mustafaev, I I

2012-01-01

The aim of the work was to study effect of bisoprolol and nebivolol therapy on the sexual function of men with AH. 20 men aged 35-55 (48 +/- 3.5) yr with grade I and II AH received either drug for 2 months. Cardiac rhythm variability (CRV) was estimated in the end of the 4-week placebo period and after 2-month monotherapy. Dopplerography of penile arteries and a questionnaire study (as described by Vasilchenko) were conducted. Both drugs significantly increased the tone of the parasympathetic component of the vegetative nervous system, improved systolic blood flow in cavernous and dorsal arteries. The questionnaire study failed to revel significant changes of the sexual function. It is concluded that biosporolol and nebivolol did not compromise the sexual function of men with AH; they improve spectral CRV characteristics and blood flow in cavernous arteries.

Angiographic predictors of 3-year patency of bypass grafts implanted on the right coronary artery system: a prospective randomized comparison of gastroepiploic artery, saphenous vein, and right internal thoracic artery grafts.

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Glineur, David; D'hoore, William; de Kerchove, Laurent; Noirhomme, Philippe; Price, Joel; Hanet, Claude; El Khoury, Gebrine

2011-11-01

Saphenous vein, in situ right gastroepiploic artery, and right internal thoracic artery grafts are routinely used to revascularize the right coronary artery. Little is known about the predictive value of objective preoperative angiographic parameters on midterm graft patency. We prospectively enrolled 210 consecutive patients undergoing coronary revascularization. Revascularization of the right coronary artery was randomly performed with the saphenous vein grafts in 81 patients and the right gastroepiploic artery in 92 patients. During the same study period, 37 patients received right coronary artery revascularization with the right internal thoracic artery used in a Y-composite fashion. All patients underwent a protocol-driven coronary angiogram 3 years after surgery. Preoperative angiographic parameters included minimum lumen diameter percent stenosis measured by quantitative angiography. A graft was considered "not functional" with patency scores of 0 to 2 and "functional" with patency scores of 3 or 4. Angiographic follow-up was 100% complete. A significant difference in the distribution of flow patterns was observed in the 3 groups. In multivariate analysis, the use of a saphenous vein graft was associated with superior graft functionality compared with the other conduits (odds ratio, 6.1; 95% confidence interval, 2.4-15). Graft function was negatively influenced by the minimum lumen diameter (odds ratio, 0.11; confidence interval, 0.05-0.25). In the right gastroepiploic artery and right internal thoracic artery groups, the proportion of functional grafts was higher when the minimum lumen diameter was below a threshold value in the third minimum lumen diameter quartile (0.64-1.30 mm). Preoperative angiography predicts graft patency in the right gastroepiploic artery and right internal thoracic artery, whereas the flow pattern in saphenous vein grafts is significantly less influenced by quantitative angiographic parameters. Copyright © 2011 The American

Comparing the effects of a cardiac rehabilitation program on functional capacity of obese and non-obese women with coronary artery disease

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Masoumeh Sadeghi

2012-06-01

Full Text Available    BACKGROUND: Obesity and sedentary lifestyle are known as important risk factors of coronary artery disease. The prevalence of obesity has increased among both men and women in the world. Therefore, the present study tried to evaluate the effectiveness of a cardiac rehabilitation program on functional capacity and body mass index (BMI in obese and non-obese women with coronary artery disease.    METHODS: In an observational study during 2000-11, we evaluated a total of 205 women with coronary artery disease who referred to the cardiac rehabilitation unit of Isfahan Cardiovascular Research Institute, Isfahan, Iran. BMI and functional capacity of each patient were assessed before and after the program. The patients were categorized as obese or non-obese based on their BMI. All participants completed the full course of the program. Data was analyzed by independent t-test and paired t-test in SPSS15.    RESULTS: Our finding showed that an 8-week cardiac rehabilitation program had significant effects on functional capacity in obese and non-obese female patients (P < 0.01 for both. The program also resulted in BMI improvements in both groups (P < 0.01 for both. Comparing the changes in the two groups did not reveal any significant differences in functional capacity. However, the two groups were significantly different in terms of BMI changes.    CONCLUSION: Cardiac rehabilitation programs are a major step in restoration of functional capacity and improvement of BMI in obese and non-obese women with coronary artery disease.         Keywords: Cardiac Rehabilitation Program, Coronary Artery Disease, Obesity, Functional Capacity, Body Mass Index.

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

Directory of Open Access Journals (Sweden)

Saltiki Katerina

2008-09-01

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.

The atypical structure and function of newborn arterial endothelium is mediated by Rho/Rho kinase signaling.

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Flavahan, Sheila; Flavahan, Nicholas A

2014-08-15

Endothelium of fetal or newborn arteries is atypical, displaying actin stress fibers and reduced nitric oxide (NO)-mediated dilatation. This study tested the hypothesis that Rho/Rho kinase signaling, which promotes endothelial stress fibers and inhibits endothelial dilatation, contributed to this phenotype. Carotid arteries were isolated from newborn [postnatal day 1 (P1)], P7, and P21 mice. Endothelial dilatation to acetylcholine (pressure myograph) was minimal at P1, increased at P7, and further increased at P21. Inhibition of Rho (C3 transferase) or Rho kinase (Y27632, fasudil) significantly increased dilatation to acetylcholine in P1 arteries but had no effect in P7 or P21 arteries. After inhibition of NO synthase (N(G)-nitro-l-arginine methyl ester), Rho kinase inhibition no longer increased acetylcholine responses in P1 arteries. Rho kinase inhibition did not affect dilatation to the NO donor DEA-NONOate. The endothelial actin cytoskeleton was labeled with phalloidin and visualized by laser-scanning microscopy. In P1 arteries, the endothelium had prominent transcytoplasmic stress fibers, whereas in P7 and P21 arteries, the actin fibers had a significantly reduced intensity and were restricted to cell borders. Phosphorylation of myosin light chains, a Rho kinase substrate, was highest in P1 endothelium and significantly reduced in P7 and P21 endothelium (laser-scanning microscopy). In P1 arteries, inhibition of Rho (C3 transferase) or Rho kinase (Y27632) significantly reduced the intensity of actin fibers, which were restricted to cell borders. Similarly, in P1 arteries, Rho inhibition significantly reduced endothelial levels of phosphorylated myosin light chains. These results indicate that the atypical function and morphology of newborn endothelium is mediated by Rho/Rho kinase signaling. Copyright © 2014 the American Physiological Society.

Functional Analysis of a Novel Genome-Wide Association Study Signal in SMAD3 That Confers Protection From Coronary Artery Disease.

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Turner, Adam W; Martinuk, Amy; Silva, Anada; Lau, Paulina; Nikpay, Majid; Eriksson, Per; Folkersen, Lasse; Perisic, Ljubica; Hedin, Ulf; Soubeyrand, Sebastien; McPherson, Ruth

2016-05-01

A recent genome-wide association study meta-analysis identified an intronic single nucleotide polymorphism in SMAD3, rs56062135C>T, the minor allele (T) which associates with protection from coronary artery disease. Relevant to atherosclerosis, SMAD3 is a key contributor to transforming growth factor-β pathway signaling. Here, we seek to identify ≥1 causal coronary artery disease-associated single nucleotide polymorphisms at the SMAD3 locus and characterize mechanisms whereby the risk allele(s) contribute to coronary artery disease risk. By genetic and epigenetic fine mapping, we identified a candidate causal single nucleotide polymorphism rs17293632C>T (D', 0.97; r(2), 0.94 with rs56062135) in intron 1 of SMAD3 with predicted functional effects. We show that the sequence encompassing rs17293632 acts as a strong enhancer in human arterial smooth muscle cells. The common allele (C) preserves an activator protein (AP)-1 site and enhancer function, whereas the protective (T) allele disrupts the AP-1 site and significantly reduces enhancer activity (Pto the (C) allele. We show that rs17293632 is an expression quantitative trait locus for SMAD3 in blood and atherosclerotic plaque with reduced expression of SMAD3 in carriers of the protective allele. Finally, siRNA knockdown of SMAD3 in human arterial smooth muscle cells increases cell viability, consistent with an antiproliferative role. The coronary artery disease-associated rs17293632C>T single nucleotide polymorphism represents a novel functional cis-acting element at the SMAD3 locus. The protective (T) allele of rs17293632 disrupts a consensus AP-1 binding site in a SMAD3 intron 1 enhancer, reduces enhancer activity and SMAD3 expression, altering human arterial smooth muscle cell proliferation. © 2016 American Heart Association, Inc.

An Innovative Technique to Assess Spontaneous Baroreflex Sensitivity with Short Data Segments: Multiple Trigonometric Regressive Spectral Analysis.

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Li, Kai; Rüdiger, Heinz; Haase, Rocco; Ziemssen, Tjalf

2018-01-01

Objective: As the multiple trigonometric regressive spectral (MTRS) analysis is extraordinary in its ability to analyze short local data segments down to 12 s, we wanted to evaluate the impact of the data segment settings by applying the technique of MTRS analysis for baroreflex sensitivity (BRS) estimation using a standardized data pool. Methods: Spectral and baroreflex analyses were performed on the EuroBaVar dataset (42 recordings, including lying and standing positions). For this analysis, the technique of MTRS was used. We used different global and local data segment lengths, and chose the global data segments from different positions. Three global data segments of 1 and 2 min and three local data segments of 12, 20, and 30 s were used in MTRS analysis for BRS. Results: All the BRS-values calculated on the three global data segments were highly correlated, both in the supine and standing positions; the different global data segments provided similar BRS estimations. When using different local data segments, all the BRS-values were also highly correlated. However, in the supine position, using short local data segments of 12 s overestimated BRS compared with those using 20 and 30 s. In the standing position, the BRS estimations using different local data segments were comparable. There was no proportional bias for the comparisons between different BRS estimations. Conclusion: We demonstrate that BRS estimation by the MTRS technique is stable when using different global data segments, and MTRS is extraordinary in its ability to evaluate BRS in even short local data segments (20 and 30 s). Because of the non-stationary character of most biosignals, the MTRS technique would be preferable for BRS analysis especially in conditions when only short stationary data segments are available or when dynamic changes of BRS should be monitored.

Cardiovascular Structure and Function in Children With Middle Aortic Syndrome and Renal Artery Stenosis.

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Rumman, Rawan K; Slorach, Cameron; Hui, Wei; Matsuda-Abedini, Mina; Langlois, Valerie; Radhakrishnan, Seetha; Lorenzo, Armando J; Amaral, Joao; Mertens, Luc; Parekh, Rulan S

2017-12-01

Middle aortic syndrome (MAS) is a narrowing of the abdominal aorta, often in conjunction with renal artery stenosis (RAS). Structure and function of the cardiovascular system are not well understood. In a prospective cross-sectional study, 35 children with MAS or RAS or both (MAS/RAS) were compared with 140 age-, sex-, and body surface area-matched healthy children. Vascular assessment included carotid intima-media thickness and carotid distensibility using B-mode ultrasound and central and peripheral pulse wave velocities using applanation tonometry. Left ventricular structure and function were assessed by 2-dimensional and speckle-tracking echocardiography. Children with MAS or RAS were 12.5±3.0 years old at enrollment, and 50% were men. Carotid intima-media thickness (0.54±0.10 versus 0.44±0.05 mm; P function (lower E/a ratio and lower e' velocities). Systolic parameters, including ejection fraction, global longitudinal and circumferential strain, were similar to controls. Our findings demonstrate that children with MAS or RAS have evidence of carotid and left ventricular remodeling, without peripheral arterial involvement, which suggests a localized disease process. Left ventricular systolic function is preserved; however, subtle changes in diastolic function are observed. Carotid vessel changes are consistent with a 5- to 10-year aging, which underscores the importance of blood pressure control. © 2017 American Heart Association, Inc.

The Effect of Physical Resistance Training on Baroreflex Sensitivity of Hypertensive Rats.

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Gomes, Moisés Felipe Pereira; Borges, Mariana Eiras; Rossi, Vitor de Almeida; Moura, Elizabeth de Orleans C de; Medeiros, Alessandra

2017-01-01

Baroreceptors act as regulators of blood pressure (BP); however, its sensitivity is impaired in hypertensive patients. Among the recommendations for BP reduction, exercise training has become an important adjuvant therapy in this population. However, there are many doubts about the effects of resistance exercise training in this population. To evaluate the effect of resistance exercise training on BP and baroreceptor sensitivity in spontaneously hypertensive rats (SHR). Rats SHR (n = 16) and Wistar (n = 16) at 8 weeks of age, at the beginning of the experiment, were randomly divided into 4 groups: sedentary control (CS, n = 8); trained control (CT, n = 8); sedentary SHR (HS, n = 8) and trained SHR (HT, n = 8). Resistance exercise training was performed in a stairmaster-type equipment (1.1 × 0.18 m, 2 cm between the steps, 80° incline) with weights attached to their tails, (5 days/week, 8 weeks). Baroreceptor reflex control of heart rate (HR) was tested by loading/unloading of baroreceptors with phenylephrine and sodium nitroprusside. Resistance exercise training increased the soleus muscle mass in SHR when compared to HS (HS 0.027 ± 0.002 g/mm and HT 0.056 ± 0.003 g/mm). Resistance exercise training did not alter BP. On the other hand, in relation to baroreflex sensitivity, bradycardic response was improved in the TH group when compared to HS (HS -1.3 ± 0.1 bpm/mmHg and HT -2.6 ± 0.2 bpm/mmHg) although tachycardia response was not altered by resistance exercise (CS -3.3 ± 0.2 bpm/mmHg, CT -3.3 ± 0.1 bpm/mmHg, HS -1.47 ± 0.06 bpm/mmHg and HT -1.6 ± 0.1 bpm/mmHg). Resistance exercise training was able to promote improvements on baroreflex sensitivity of SHR rats, through the improvement of bradycardic response, despite not having reduced BP. Os barorreceptores atuam como reguladores da pressão arterial (PA); no entanto, sua sensibilidade encontra-se prejudicada em pacientes hipertensos. Dentre as recomendações para a redução da PA, o treinamento f

Evaluation of ventricular function in patients with coronary artery disease

International Nuclear Information System (INIS)

Rocco, T.P.; Dilsizian, V.; Fischman, A.J.; Strauss, H.W.

1989-01-01

The recent expansion of interventional cardiovascular technologies has stimulated a concomitant expansion of noninvasive cardiac studies, both to assist in diagnosis and to evaluate treatment outcomes. Radionuclide ventricular function studies provide a reliable, reproducible means to quantify global left ventricular systolic performance, a critical determinant of prognosis in patients with cardiovascular disease. In addition, the ability to evaluate regional left ventricular wall motion and to assess ventricular performance during exercise have secured a fundamental role for such studies in the screening and treatment of patients with coronary artery disease. Radionuclide techniques have been extended to the evaluation of left ventricular relaxation/filling events, left ventricular systolic/diastolic function in the ambulatory setting, and with appropriate technical modifications, to the assessment of right ventricular performance at rest and with exercise. As a complement to radionuclide perfusion studies, cardiac blood-pool imaging allows for thorough noninvasive description of cardiac physiology and function in both normal subjects and in patients with a broad range of cardiovascular diseases. 122 references

Elastase-2, a Tissue Alternative Pathway for Angiotensin II Generation, Plays a Role in Circulatory Sympathovagal Balance in Mice.

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Becari, Christiane; Durand, Marina T; Guimaraes, Alessander O; Lataro, Renata M; Prado, Cibele M; de Oliveira, Mauro; Candido, Sarai C O; Pais, Paloma; Ribeiro, Mauricio S; Bader, Michael; Pesquero, Joao B; Salgado, Maria C O; Salgado, Helio C

2017-01-01

In vitro and ex vivo experiments indicate that elastase-2 (ELA-2), a chymotrypsin-serine protease elastase family member 2A, is an alternative pathway for angiotensin II (Ang II) generation. However, the role played by ELA-2 in vivo is unclear. We examined ELA-2 knockout (ELA-2KO) mice compared to wild-type (WT) mice and determined whether ELA-2 played a role in hemodynamics [arterial pressure (AP) and heart rate (HR)], cardiocirculatory sympathovagal balance and baroreflex sensitivity. The variability of systolic arterial pressure (SAP) and pulse interval (PI) for evaluating autonomic modulation was examined for time and frequency domains (spectral analysis), whereas a symbolic analysis was also used to evaluate PI variability. In addition, baroreflex sensitivity was examined using the sequence method. Cardiac function was evaluated echocardiographically under anesthesia. The AP was normal whereas the HR was reduced in ELA-2KO mice (425 ± 17 vs. 512 ± 13 bpm from WT). SAP variability and baroreflex sensitivity were similar in both strains. The LF power from the PI spectrum (33.6 ± 5 vs. 51.8 ± 4.8 nu from WT) and the LF/HF ratio (0.60 ± 0.1 vs. 1.45 ± 0.3 from WT) were reduced, whereas the HF power was increased (66.4 ± 5 vs. 48.2 ± 4.8 nu from WT) in ELA-2KO mice, indicating a shift toward parasympathetic modulation of HR. Echocardiographic examination showed normal fractional shortening and an ejection fraction in ELA-2KO mice; however, the cardiac output, stroke volume, and ventricular size were reduced. These findings provide the first evidence that ELA-2 acts on the sympathovagal balance of the heart, as expressed by the reduced sympathetic modulation of HR in ELA-2KO mice.

Effect of simvastatin in the autonomic system is dependent on the increased gain/sensitivity of the baroreceptors

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Moreira, Edson D; Mostarda, Cristiano T; Moraes-Silva, Ivana C; Ferreira, Janaina B; dos Santos, Fernando; Lacchini, Silvia; De Angelis, Kátia; Rodrigues, Bruno; Irigoyen, Maria Cláudia

2013-01-01

A number of mechanisms have been proposed to explain the pleiotropic effect of statin therapy to reduce sympathetic outflow in cardiovascular disease. We tested the hypothesis that statin treatment could improve baroreflex gain-sensitivity triggered by morphological adaptations in the mechanoreceptor site, thus reducing sympathetic activity, regardless of arterial pressure (AP) level reduction. Male spontaneously hypertensive rats (SHR) were divided into control (SHR, n = 8) and SHR-simvastatin (5 mg/kg/day, for 7 days) (SHR-S, n = 8). After treatment, AP, baroreflex sensitivity (BRS) in response to AP-induced changes, aortic depressor nerve activity, and spectral analyses of pulse interval (PI) and AP variabilities were performed. Internal and external carotids were prepared for morphoquantitative evaluation. Although AP was similar between groups, sympathetic modulation, represented by the low frequency band of PI (SHR: 6.84 ± 3.19 vs. SHR-S: 2.41 ± 0.96 msec2) and from systolic AP variability (SHR: 3.95 ± 0.36 vs. SHR-S: 2.86 ± 0.18 mmHg2), were reduced in treated animals. In parallel, simvastatin induced an increase of 26% and 21% in the number of elastic lamellae as well as a decrease of 9% and 25% in the carotid thickness in both, external and internal carotid, respectively. Moreover, improved baroreceptor function (SHR: 0.78 ± 0.03 vs. SHR-S: 1.06 ± 0.04% mv/mmHg) was observed in addition to a 115% increase in aortic depressor nerve activity in SHR-S rats. Therefore, our data suggest that the reduction of sympathetic outflow in hypertension by simvastatin treatment may be triggered by structural changes in the carotid arteries and increased BRS in response to an improvement of the baroreceptors discharge and consequently of the afferent pathway of the baroreflex arch. PMID:24303130

Impact of arterial occlusion during partial nephrectomy on residual renal function. An evaluation with {sup 99m}technetium-dimercaptosuccinic acid scintigraphy

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Kondo, Tsunenori; Nakazawa, Hayakazu; Ito, Fumio; Onitsuka, Shiro; Ryoji, Osamu; Yago, Rie; Hashimoto, Yasunobu; Toma, Hiroshi [Tokyo Women' s Medical Coll. (Japan)

2002-08-01

Partial nephrectomy (PNx) has been performed with temporary renal arterial occlusion and in situ renal hypothermia (conventional PNx). However, the impact of temporary renal arterial occlusion on residual renal function has not been well assessed. To address this question, we performed renal scintigraphy with {sup 99m}technetium-dimercaptosuccinic acid (DMSA) for the quantitative measurement of postoperative residual renal function after conventional PNx and partial nephrectomy without arterial occlusion (non-clamping PNx). Thirty-four patients underwent postoperative DMSA scintigraphy after PNx for renal cell carcinoma. No obvious difference in preoperative renal function between the diseased kidney and the contralateral kidney was found in any of the patients. Of these patients, 24 underwent conventional PNx, and 10 underwent non-clamping PNx. Residual renal function was evaluated using the relative DMSA uptake of the operated kidney. The relative DMSA uptake of the operated kidney was 39.9{+-}7.3% (25.1-58.8) after conventional PNx compared to 34.8{+-}8.9% (13.5-45.5) after non-clamping PNx. This difference was not statistically significant (P=0.15). Total ischemic time during conventional PNx had no adverse influence on the residual renal function. In the analysis of the other determinant factors influencing residual renal function, tumor size was the only significant factor that inversely correlated with the relative DMSA uptake. Our results showed that arterial clamping during PNx has no negative impact on the functional residual capacity as long as in situ renal hypothermia is adequately performed. (author)

[Effect of monotherapy with nebivolol, bisoprolol, carvedilol on the state of vegetative nervous system and sexual function in men with arterial hypertension].

Science.gov (United States)

Mustafaev, I I; Nurmamedova, G S

2013-01-01

Aim of the study was to assess effect of monotherapy with nebivolol, bisoprolol, carvedilol for 2 months on sexual function in men with arterial hypertension (AH). Men with 1-2 degree of AH (n=75, age 35-55 years, mean age 48+/-3,5 years) received monotherapy with these drugs for 2 months. Registration of parameters of heart rate variability (HRV), Dopplerography of penile arteries, and the Vasilchenko questionnaire were implemented at the end of 4 months of placebo period and after 2 months of therapy with a study drug. Therapy with bisoprolol, carvedilol, and nebivolol was associated with significant elevation of parasympathetic part of vegetative nervous system tone, improvement of systolic blood flow in cavernous and dorsal arteries. Analysis of data obtained by Vasilchenko questionnaire demonstrated improvement of psychic and erectile components of sexual function. Thus bisoprolol, carvedilol, and nebivolol did not worsen sexual function of men with AH, improved spectral parameters of HRV and vascular blood flow in arteries of cavernous bodies.

Baroreflexes of the rat. V. Tetanus-induced potentiation of ADN A-fiber responses at the NTS.

Science.gov (United States)

Tang, Xiaorui; Dworkin, Barry R

2007-12-01

In a long-term neuromuscular blocked (NMB) rat preparation, tetanic stimulation of the aortic depressor nerve (ADN) enhanced the A-fiber evoked responses (ERs) in the cardiovascular region, the nucleus of the solitary tract (dmNTS). The potentiation persisted for at least several hours and may be a mechanism for adaptive adjustment of the gain of the baroreflex, with functional implications for blood pressure regulation. Using a capacitance electrode, we selectively stimulated A-fibers and acquired a stable 10-h "A-fiber only" ER baseline at the dmNTS. Following baseline, an A+C-fiber activating tetanus was applied to the ADN. The tetanus consisted of 1,000 "high current" pulses (10 trains; 300 mus, 100 Hz, 1 s), with intertrain interval of 9 s. A 10-h A-fiber only posttetanic test phase repeated the stimulus pattern of the baseline. Fourteen tetanus experiments were done in 12 rats. Compared with the baseline before tetanus, the A-fiber ER magnitudes of posttetanus hours were larger [F(13, 247) = 3.407, P ADN A+C fiber-activating tetanus produced increases in the magnitude of the A-fiber ERs in the dmNTS that persisted for several hours. In an additional rat, application of an NMDA receptor antagonist, prior to the tetanus, blocked the potentiation effect. The stimulus protocols, magnitude and duration of the effect, and pharmacology resemble associative long-term potentiation (LTP).

Comparison of systemic right ventricular function in transposition of the great arteries after atrial switch and congenitally corrected transposition of the great arteries.

Science.gov (United States)

Morcos, Michael; Kilner, Philip J; Sahn, David J; Litt, Harold I; Valsangiacomo-Buechel, Emanuela R; Sheehan, Florence H

2017-12-01

In patients with transposition of the great arteries corrected by interatrial baffle (TGA) and those with congenitally corrected transposition of the great arteries (ccTGA) the right ventricle (RV) is subjected to systemic pressure and fails prematurely. Previous studies have demonstrated RV dysfunction may be more pronounced in patients with TGA. The present study sought to compare patients with TGA and ccTGA using three-dimensional (3D) techniques to comprehensively analyze the shape, volume, global and regional function in the systemic RV. We compared RV size, shape, and regional and global function in 25 patients with TGA, 17 patients with ccTGA, and 9 normal subjects. The RVs were reconstructed from cardiac Magnetic Resonance Images for 3D analyses. Compared to normal, the RV in TGA and ccTGA was dilated, rounded, and reduced in function. Compared to each other, TGA and ccTGA patients had similar RV size and shape. Global RV function was lower in TGA than ccTGA when assessed from ejection fraction (EF) (30 ± 7 vs. 35 ± 7, p = 0.02) and from normalized tricuspid annular systolic plane excursion (TAPSE) (0.10 ± 0.04 vs. 0.18 ± 0.04, p < 0.01). Basilar RV function was poorer in the TGA patients when compared to ccTGA. The systemic RVs in both TGA and ccTGA are dilated, spherical, and poorly functioning. Compared to ccTGA, TGA RVs have reduced TAPSE and worse basilar hypokinesis.

Effect of periodontal therapy on arterial structure and function among aboriginal australians: a randomized, controlled trial.

Science.gov (United States)

Kapellas, Kostas; Maple-Brown, Louise J; Jamieson, Lisa M; Do, Loc G; O'Dea, Kerin; Brown, Alex; Cai, Tommy Y; Anstey, Nicholas M; Sullivan, David R; Wang, Hao; Celermajer, David S; Slade, Gary D; Skilton, Michael R

2014-10-01

Observational studies and nonrandomized trials support an association between periodontal disease and atherosclerotic vascular disease. Both diseases occur frequently in Aboriginal Australians. We hypothesized that nonsurgical periodontal therapy would improve measures of arterial function and structure that are subclinical indicators of atherosclerotic vascular disease. This parallel-group, randomized, open label clinical trial enrolled 273 Aboriginal Australians aged ≥18 years with periodontitis. Intervention participants received full-mouth periodontal scaling during a single visit, whereas controls received no treatment. Prespecified primary end points measured 12-month change in carotid intima-media thickness, an indicator of arterial structure, and 3- and 12-month change in pulse wave velocity, an indicator of arterial function. ANCOVA used complete case data to evaluate treatment group differences. End points could be calculated for 169 participants with follow-up data at 3 months and 168 participants at 12 months. Intima-media thickness decreased significantly after 12 months in the intervention group (mean reduction=-0.023 [95% confidence interval {CI}, -0.038 to -0.008] mm) but not in the control group (mean increase=0.002 [95% CI, -0.017 to 0.022] mm). The difference in intima-media thickness change between treatment groups was statistically significant (-0.026 [95% CI, -0.048 to -0.003] mm; P=0.03). In contrast, there were no significant differences between treatment groups in pulse wave velocity at 3 months (mean difference, 0.06 [95% CI, -0.17 to 0.29] m/s; P=0.594) or 12 months (mean difference, 0.21 [95% CI, -0.01 to 0.43] m/s; P=0.062). Periodontal therapy reduced subclinical arterial thickness but not function in Aboriginal Australians with periodontal disease, suggesting periodontal disease and atherosclerosis are significantly associated. © 2014 American Heart Association, Inc.

Superselective intra-arterial chemoradiotherapy for advanced head and neck cancers. Evaluation of preservation of organ function

International Nuclear Information System (INIS)

Akisada, Takeshi; Harada, Tamotsu; Imai, Shigeki; Gyoten, Masayuki; Hiraoka, Takashi

2008-01-01

The objective of this study was to evaluate preservation of organ function in the treatment of superselective intra-arterial chemoradiotherapy for advanced head and neck cancers. Among 96 patients receiving concomitant radiation and intra-arterial docetaxel, systemic cisplatin and 5-fluorouracil (FU) chemotherapy, we identified laryngeal preservation rate, studied tracheostomy cases and gastrostomy cases, and evaluated videofluoroscopic examination and videoendoscopy. Laryngeal preservation rate of hypopharyngeal cancer is very high at 96.2%, and that of laryngeal cancer is high at 71.4%. Videofluoroscopic examination revealed improved swallowing function in 2 of 12, no change in 3, slightly worse in 5, and worse in 2 patients. Following treatment, the incidence of aspiration increased to 4 patients. Videoendoscopy revealed residual vallecula in a few cases. Only 7 patients (7.3%) required a tracheostomy and 4 patients (4.2%) required a gastrostomy. Most of the patients are able to swallow after chemoradiation. Our new chemoradiation protocol is as good as other treatment modalities for maintaining organ preservation and function. (author)

The new technique of using the epigastric arteries in renal transplantation with multiple renal arteries

Directory of Open Access Journals (Sweden)

Mohammad Ali Amirzargar

2013-01-01

Full Text Available The most common anatomic variant seen in the donor kidneys for renal transplantation is multiple renal arteries (MRA, which can cause an increased risk of complications. We describe the long-term outcomes of 16 years of experience in 76 kidney transplantations with MRAs. In a new reconstruction technique, we remove arterial clamps after anastomosing the donor to the recipient′s main renal vessels, which cause backflow from accessory arteries to prevent thrombosis. By this technique, we reduce the ischemic times as well as the operating times. Both in live or cadaver donor kidneys, lower polar arteries were anastomosed to the inferior epigastric artery and upper polar arteries were anastomosed to the superior epigastric arteries. Injection of Papaverine and ablation of sympathic nerves of these arteries dilate and prevent them from post-operative spasm. Follow-up DTPA renal scan in all patients showed good perfusion and function of the transplanted kidney, except two cases of polar arterial thrombosis. Mean creatinine levels during at least two years of follow-up remained acceptable. Patient and graft survival were excellent. No cases of ATN, hypertension, rejection and urologic complications were found. In conclusion, this technique can be safely and successfully utilized for renal transplantation with kidneys having MRAs, and may be associated with a lower complication rate and better graft function compared with the existing techniques.

Evaluation of coronary artery disease by functional imaging from equilibrium radionuclide ventriculography

International Nuclear Information System (INIS)

He Zuoxiang

1992-01-01

Functional imagings were performed in 10 normals, 9 subjects with Non coronary Artery disease (NCAD), 33 CAD patients with documented MI (CAD-WMI) and 20 without MI (CAD-NMI). The sensitivity of LVGEF, LVREF and phase analysis at rest for detecting CAD-WMI was 66.7%, 78.8%, 93.9% respectively. LVGEF, LVREF during exercise for assessing CAD-NMI had the sensitivity of 90%, 80%, respectively, while specificity 90%. Early LVEF decrease, > 10% LVEF decrease and abnormal response at > 7 sectors during exercise were observed in 2 patients with 3 vessel. In conclusion, functional imaging were very useful for detecting CAD and evaluating its extent

Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats.

Science.gov (United States)

Klippel, Brunella F; Duemke, Licia B; Leal, Marcos A; Friques, Andreia G F; Dantas, Eduardo M; Dalvi, Rodolfo F; Gava, Agata L; Pereira, Thiago M C; Andrade, Tadeu U; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

2016-01-01

It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated. SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1-adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis. Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1.6- and ~1.5-fold, respectively

Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats

Science.gov (United States)

Klippel, Brunella F.; Duemke, Licia B.; Leal, Marcos A.; Friques, Andreia G. F.; Dantas, Eduardo M.; Dalvi, Rodolfo F.; Gava, Agata L.; Pereira, Thiago M. C.; Andrade, Tadeu U.; Meyrelles, Silvana S.; Campagnaro, Bianca P.; Vasquez, Elisardo C.

2016-01-01

Aims: It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated. Methods: SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1−adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis. Results: Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1

[Obesity as pathology of adipocytes: number of cells, volume of arterial bloodstream,local pools of circulation in vivo, natriuretic peptides and arterial hypertension].

Science.gov (United States)

Titov, V N; Dmitriev, V A

2015-03-01

The non-specific systemic biological reaction of arterial pressure from the level of organism. vasomotor center and proximal section of arterial bloodstream is appealed to compensate disorders of metabolism and microcirculation in distal section of arteries. This phenomenon occurs in several cases. The primarily local disorders of metabolism at autocrine level, physiological (aphysiological) death of cells, "littering" of intercellular medium become the cause of disorder of microcirculation in paracrin cenosises and deteriorate realization of biological functions of homeostasis, trophology, endoecology and adaptation. The local compensation of affected perfusion in paracrin cenosises at the expense of function of peripheral peristaltic pumps, redistribution of local bloodflow in biological reaction of endothelium-depended vaso-dilation has no possibility to eliminate disorders in realization of biological functions. The systemic increase of arterial pressure under absence of specific symptoms of symptomatic arterial hypertension is a test to detect disorder of biological functions of homeostasis, trophology, biological function of endoecology and adaptation. Allforms of arterial hypertension develop by common algorithm independently from causes of disorders of blood flow, microcirculation in distal section of arteries. The non-specific systemic compensation ofdisorders of metabolism from level of organism, in proximal section of arterial bloodstream always is the same one and results in aphysiological alterations in organs-targets. To comprehend etiological characteristics of common pathogenesis of arterial hypertension is possible in case of application of such technically complicated and still unclear in differential diagnostic of deranged functions modes of metabolomics.

Effect of PPARγ Inhibition during Pregnancy on Posterior Cerebral Artery Function and Structure

Directory of Open Access Journals (Sweden)

Siu-Lung eChan

2010-08-01

Full Text Available Peroxisome proliferator-activated receptor-γ (PPARγ, a ligand-activated transcription factor, has protective roles in the cerebral circulation, and, is highly activated during pregnancy. Thus, we hypothesized that PPARγ is involved in the adaptation of cerebral vasculature to pregnancy. Nonpregnant (NP and late-pregnant (LP rats were treated with a specific PPARγ inhibitor GW9662 (10 mg/kg/day, in food or vehicle for 10 days and vascular function and structural remodeling were determined in isolated and pressurized posterior cerebral arteries (PCA. Expression of PPARγ and angiotensin type 1 receptor (AT1R in cerebral (pial vessels was determined by real-time RT-PCR. PPARγ inhibition decreased blood pressure and increased blood glucose in NP rats, but not in LP rats. PPARγ inhibition reduced dilation to acetylcholine and sodium nitroprusside in PCA from NP (p<0.05 vs. LP-GW, but not LP rats. PPARγ inhibition tended to increase basal tone and myogenic activity in PCA from NP rats, but not LP rats. Structurally, PPARγ inhibition increased wall-thickness in PCA from both NP and LP rats (p<0.05, but increased distensibility only in PCA from NP rats. Pregnancy decreased expression of PPARγ and AT1R (p<0.05 in cerebral arteries that was not affected by GW9662 treatment. These results suggest that PPARγ inhibition had significant effects on the function and structure of PCA in the NP state, but appeared to have less influence during pregnancy. Down-regulation of PPARγ and AT1R in cerebral arteries may be responsible for the lack of effect of PPARγ in cerebral vasculature and may be part of the vascular adaptation to pregnancy.

Arterial function parameters in patients with metabolic syndrome and severe hypertriglyceridemia.

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Rinkūnienė, Egidija; Butkutė, Eglė; Puronaitė, Roma; Petrulionienė, Žaneta; Dženkevičiūtė, Vilma; Kasiulevičius, Vytautas; Laucevičius, Aleksandras

Hypertriglyceridemia (hTG) is 1 of the dyslipidemia manifestations in patients with metabolic syndrome (MetS). However, for several decades, the role of hTG in cardiovascular risk was not well established. The aim of this study was to assess the parameters of the vascular structure and function in patients with MetS and different degree of hTG. Patients (aged 40-65 years) with MetS were divided into 3 groups by triglyceride (TG) levels according to National Cholesterol Education Program Adult Treatment Panel III Guidelines: severe hTG (TG ≥ 500 mg/dL), moderate hTG (TG 200-499 mg/dL), and a control (TG severe TG was observed in 9.6% (n = 100) of patients. Overall TG concentration was 231.17 ± 184.23 mg/dL; in severe hTG group, TG concentration was 795.36 ± 368.45 mg/dL, in moderate hTG group 285.20 ± 70.86 mg/dL, and 112.48 ± 24.80 mg/dL in control group. AIxHR75 and IMT were the lowest in the severe hTG group (P severe hTG have lower IMT and AIxHR75 and higher PWV and mean arterial pressure. Many factors could affect arterial parameters, and more research are needed to investigate arterial parameters and hTG connection. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Simplified quantification of small animal [{sup 18}F]FDG PET studies using a standard arterial input function

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Meyer, Philipp T. [University Hospital Aachen, Department of Neurology, Aachen (Germany); Circiumaru, Valentina; Thomas, Daniel H. [University of Pennsylvania, Department of Radiology, Philadelphia (United States); Cardi, Christopher A.; Bal, Harshali; Acton, Paul D. [Thomas Jefferson University, Department of Radiology, Philadelphia (United States)

2006-08-15

Arterial input function (AIF) measurement for quantification of small animal PET studies is technically challenging and limited by the small blood volume of small laboratory animals. The present study investigated the use of a standard arterial input function (SAIF) to simplify the experimental procedure. Twelve [{sup 18}F]fluorodeoxyglucose ([{sup 18}F]FDG) PET studies accompanied by serial arterial blood sampling were acquired in seven male Sprague-Dawley rats under isoflurane anaesthesia without (every rat) and with additional (five rats) vibrissae stimulation. A leave-one-out procedure was employed to validate the use of a SAIF with individual scaling by one (1S) or two (2S) arterial blood samples. Automatic slow bolus infusion of [{sup 18}F]FDG resulted in highly similar AIF in all rats. The average differences of the area under the curve of the measured AIF and the individually scaled SAIF were 0.11{+-}4.26% and 0.04{+-}2.61% for the 1S (6-min sample) and the 2S (4-min/43-min samples) approach, respectively. The average differences between the cerebral metabolic rates of glucose (CMR{sub glc}) calculated using the measured AIF and the scaled SAIF were 1.31{+-}5.45% and 1.30{+-}3.84% for the 1S and the 2S approach, respectively. The use of a SAIF scaled by one or (preferably) two arterial blood samples can serve as a valid substitute for individual AIF measurements to quantify [{sup 18}F]FDG PET studies in rats. The SAIF approach minimises the loss of blood and should be ideally suited for longitudinal quantitative small animal [{sup 18}F]FDG PET studies. (orig.)

Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans.

Science.gov (United States)

Brunt, Vienna E; Howard, Matthew J; Francisco, Michael A; Ely, Brett R; Minson, Christopher T

2016-09-15

A recent 30 year prospective study showed that lifelong sauna use reduces cardiovascular-related and all-cause mortality; however, the specific cardiovascular adaptations that cause this chronic protection are currently unknown. We investigated the effects of 8 weeks of repeated hot water immersion ('heat therapy') on various biomarkers of cardiovascular health in young, sedentary humans. We showed that, relative to a sham group which participated in thermoneutral water immersion, heat therapy increased flow-mediated dilatation, reduced arterial stiffness, reduced mean arterial and diastolic blood pressure, and reduced carotid intima media thickness, with changes all on par or greater than what is typically observed in sedentary subjects with exercise training. Our results show for the first time that heat therapy has widespread and robust effects on vascular function, and as such, could be a viable treatment option for improving cardiovascular health in a variety of patient populations, particularly those with limited exercise tolerance and/or capabilities. The majority of cardiovascular diseases are characterized by disorders of the arteries, predominantly caused by endothelial dysfunction and arterial stiffening. Intermittent hot water immersion ('heat therapy') results in elevations in core temperature and changes in cardiovascular haemodynamics, such as cardiac output and vascular shear stress, that are similar to exercise, and thus may provide an alternative means of improving health which could be utilized by patients with low exercise tolerance and/or capabilities. We sought to comprehensively assess the effects of 8 weeks of heat therapy on biomarkers of vascular function in young, sedentary subjects. Twenty young, sedentary subjects were assigned to participate in 8 weeks (4-5 times per week) of heat therapy (n = 10; immersion in a 40.5°C bath sufficient to maintain rectal temperature ≥ 38.5°C for 60 min per session) or thermoneutral water

Influence of pleural drain insertion in lung function of patients undergoing coronary artery bypass grafting.

Science.gov (United States)

Ozelami Vieira, Irinea Beatriz Carvalho; Vieira, Fabiano F; Abrão, João; Gastaldi, Ada Clarice

2012-01-01

Longitudinal, prospective, randomized, blinded Trial to assess the influence of pleural drain (non-toxic PVC) site of insertion on lung function and postoperative pain of patients undergoing coronary artery bypass grafting in the first three days post-surgery and immediately after chest tube removal. Thirty six patients scheduled for elective myocardial revascularization with cardiopulmonary bypass (CPB) were randomly allocated into two groups: SX group (subxiphoid) and IC group (intercostal drain). Spirometry, arterial blood gases, and pain tests were recorded. Thirty one patients were selected, 16 in SX group and 15 in IC group. Postoperative (PO) spirometric values were higher in SX than in IC group (ppleural drain location on breathing. PaO(2) on the second PO increased significantly in SX group compared with IC group (pDrain with insertion in the subxiphoid region causes less change in lung function and discomfort, allowing better recovery of respiratory parameters. Copyright © 2012 Elsevier Editora Ltda. All rights reserved.

Application of the Polytron 1000 VR for functional diagnosis and interventional examination of arteries of the lower extremity: First clinical results

Energy Technology Data Exchange (ETDEWEB)

Kueffer, G.; Ziegler, L.; Hahn, D.

1989-01-01

The article reports the clinical experience gained with the POLYTRON-1000 VR system which has been used for all functional diagnostic tasks for detection of compression syndrome of the popliteal artery, and for diagnostic preparation and execution of atherectomy of pelvic and leg arteries with the Simpson catheter.

Baroreflex sensitivity in children and adolescents: physiology, hypertension, obesity, diabetes mellitus.

Science.gov (United States)

Honzíková, N; Závodná, E

2016-12-13

The increased prevalence of obesity in children and its complications have led to a greater interest in studying baroreflex sensitivity (BRS) in children. This review of BRS in children and adolescents includes subtopics on: 1. Resting values of BRS and their reproducibility, 2. Genetics of BRS, 3. The role of a primarily low BRS and obesity in the development of hypertension, and 4. Association of diabetes mellitus, BRS, and obesity. The conclusions specific to this age follow from this review: 1. The mean heart rate (HR) influences the measurement of BRS. Since the mean HR decreases during adolescence, HR should be taken into account. 2. A genetic dependency of BRS was found. 3. Low BRS values may precede pathological blood-pressure elevation in children with white-coat hypertension. We hypothesize that low BRS plays an active role in the emergence of hypertension in youth. A contribution of obesity to the development of hypertension was also found. We hypothesize that both factors, a primarily low BRS and obesity, are partially independent risk factors for hypertension in youths. 4. In diabetics, a low BRS compared to healthy children can be associated with insulin resistance. A reversibility of the BRS values could be possible after weight loss.

Comparative in vivo analysis of the role of the adventitia and the endothelium on arterial mechanical function: relevance for aortic counterpulsation.

Science.gov (United States)

Bia, Daniel; Zócalo, Yanina; Wray, Sandra; Cabrera-Fischer, Edmundo I

2017-06-09

The comparative effect of the intimal and adventitial layers on arterial biomechanics control, in basal and altered conditions, remains to be elucidated. This study aimed (1) to characterize the arterial conduit (CF) and buffering (distensibility) function of the iliac arteries in in vivo animals, in which the intimal and adventitial layers were removed; (2) to determine the effects of intra-aortic ballon pumping (IABP) on simultaneously de-adventitialized (DA) and de-endothelialized (DE) iliac arteries before and after induced heart failure. Pressure and diameter signals were measured in the iliac arteries of sheep (n = 7) in which the adventitial and intima layer were removed. Intra-aortic balloon pump (IABP) assistance was used in a control state and after heart failure induction. Both DE and DA determined significant changes in arterial diameter, distensibility and CF. Changes were higher after DA than after DE in terms of distensibility and CF (p<0.05). DA followed by DE (DA + DE) showed significant increases in arterial diameter and CF, accompanied by a decrease in distensibility (p<0.05) with respect to intact arteries. Heart failure induction caused significant hemodynamic changes without modifying the already impaired local biomechanical parameters. Nonsignificant improvements in the biomechanical parameters of DA + DE iliac arteries were observed during IABP before and after heart failure induction. Biomechanical changes caused by DA of iliac arteries were more important than those observed after DE. The DA + DE arteries showed significant differences with respect to intact arteries and with DA or DE arteries. IABP-related effects on arterial mechanics were absent in DA + DE arteries.

Cardiac magnetic resonance imaging-derived pulmonary artery distensibility index correlates with pulmonary artery stiffness and predicts functional capacity in patients with pulmonary arterial hypertension

International Nuclear Information System (INIS)

Kang, Ki-Woon; Chang, Hyuk-Jae; Kim, Young-Jin; Choi, Byoung-Wook; Yang, Woo-In; Shim, Chi-Young; Ha, Jongwon; Chung, Namsik; Lee, Hye-Sun

2011-01-01

Increased stiffness of the pulmonary vascular bed is known to increase mortality in patients with pulmonary arterial hypertension (PAH); and pulmonary artery (PA) stiffness is also thought to be associated with exercise capacity. The purpose of the present study was to investigate whether cardiac magnetic resonance imaging (CMRI)-derived PA distensibility index correlates with PA stiffness estimated on right heart catheterization (RHC) and predicts functional capacity (FC) in patients with PAH. Thirty-five consecutive PAH patients (23% male, mean age, 44±13 years; 69% idiopathic) underwent CMRI, RHC, and 6-min walk test (6MWT). PA distensibility indices were derived from cross-sectional area change (%) in the transverse view, perpendicular to the axis of the main PA, on CMRI [(maximum area-minimum area)/minimum area during cardiac cycle]. Among the PA stiffness indices, pulmonary vascular resistance (PVR) and PA capacitance were calculated using hemodynamic dataset from RHC. CMRI-derived PA distensibility was inversely correlated with PVR (R 2 =0.34, P 2 =0.35, P 2 =0.61, P<0.001). Furthermore, PA distensibility <20% predicted poor FC (<400 m in 6MWT) with a sensitivity of 82% and a specificity of 94%. Non-invasive CMRI-derived PA distensibility index correlates with PA stiffness and can predict FC in patients with PAH. (author)

Pulmonary artery wave propagation and reservoir function in conscious man: impact of pulmonary vascular disease, respiration and dynamic stress tests.

Science.gov (United States)

Su, Junjing; Manisty, Charlotte; Simonsen, Ulf; Howard, Luke S; Parker, Kim H; Hughes, Alun D

2017-10-15

Wave travel plays an important role in cardiovascular physiology. However, many aspects of pulmonary arterial wave behaviour remain unclear. Wave intensity and reservoir-excess pressure analyses were applied in the pulmonary artery in subjects with and without pulmonary hypertension during spontaneous respiration and dynamic stress tests. Arterial wave energy decreased during expiration and Valsalva manoeuvre due to decreased ventricular preload. Wave energy also decreased during handgrip exercise due to increased heart rate. In pulmonary hypertension patients, the asymptotic pressure at which the microvascular flow ceases, the reservoir pressure related to arterial compliance and the excess pressure caused by waves increased. The reservoir and excess pressures decreased during Valsalva manoeuvre but remained unchanged during handgrip exercise. This study provides insights into the influence of pulmonary vascular disease, spontaneous respiration and dynamic stress tests on pulmonary artery wave propagation and reservoir function. Detailed haemodynamic analysis may provide novel insights into the pulmonary circulation. Therefore, wave intensity and reservoir-excess pressure analyses were applied in the pulmonary artery to characterize changes in wave propagation and reservoir function during spontaneous respiration and dynamic stress tests. Right heart catheterization was performed using a pressure and Doppler flow sensor tipped guidewire to obtain simultaneous pressure and flow velocity measurements in the pulmonary artery in control subjects and patients with pulmonary arterial hypertension (PAH) at rest. In controls, recordings were also obtained during Valsalva manoeuvre and handgrip exercise. The asymptotic pressure at which the flow through the microcirculation ceases, the reservoir pressure related to arterial compliance and the excess pressure caused by arterial waves increased in PAH patients compared to controls. The systolic and diastolic rate constants

Estimating the arterial input function from dynamic contrast-enhanced MRI data with compensation for flow enhancement (I): Theory, method, and phantom experiments

NARCIS (Netherlands)

van Schie, Jeroen J. N.; Lavini, Cristina; van Vliet, Lucas J.; Vos, Frans M.

2017-01-01

The arterial input function (AIF) represents the time-dependent arterial contrast agent (CA) concentration that is used in pharmacokinetic modeling. To develop a novel method for estimating the AIF from dynamic contrast-enhanced (DCE-) MRI data, while compensating for flow enhancement. Signal

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

International Nuclear Information System (INIS)

Poreba, Rafal; Gac, Pawel; Poreba, Malgorzata; Antonowicz-Juchniewicz, Jolanta; Andrzejak, Ryszard

2011-01-01

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 (β), augmentation index (AI) and one-point pulse wave velocity (PWV-β) 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 (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

Central Arterial Function Measured by Non-invasive Pulse Wave Analysis is Abnormal in Patients with Duchenne Muscular Dystrophy.

Science.gov (United States)

Ryan, Thomas D; Parent, John J; Gao, Zhiqian; Khoury, Philip R; Dupont, Elizabeth; Smith, Jennifer N; Wong, Brenda; Urbina, Elaine M; Jefferies, John L

2017-08-01

Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder caused by mutation of dystrophin. Cardiovascular involvement includes dilated cardiomyopathy. Non-invasive assessment of vascular function has not been evaluated in DMD. We hypothesize arterial wave reflection is abnormal in patients with DMD. Pulse wave analysis was performed on DMD patients with a SphygmoCor SCOR-PVx System to determine central blood pressure and augmentation index (AIx) as an assessment of arterial wave reflection. Results were compared to a control group. A total of 43 patients with DMD were enrolled, and compared to 43 normal controls. Central systolic blood pressure was lower, while both AIx-75 (7.8 ± 9.6% vs. 2.1 ± 10.4%, p 0.01, DMD vs. normal) and AIx-not corrected (16.8 ± 10.1% vs. -3.6 ± 10.9, p wave reflection when compared to normal controls, which may represent increased arterial stiffness. Overall there appears to be no effect on ventricular systolic function, however the long-term consequence in this group is unknown. Further study is required to determine the mechanism of these differences, which may be related to the effects of systemic steroids or the role of dystrophin in vascular function.

A content analysis of peripheral arterial disease patient-reported outcome measures using the International Classification of Functioning, Disability and Health.

Science.gov (United States)

Osborne, Candice Lee; Kauvar, David Seth

2017-10-17

The purpose of this study was to link, classify and describe the content of peripheral arterial disease (PAD)-specific patient-reported outcome measures using the International Classification of Functioning. The results were then analyzed to determine if these assessments provide clinicians and researchers with a comprehensive understanding of the lived experience of patients with PAD. Each meaningful concept in identified PAD assessments was linked to the International Classification of Functioning, Disability and Health to determine included and excluded content areas. An overall perspective was assigned to each assessment item. Inter-rater reliability was established using a kappa statistic. The body functions component is most frequently addressed overall followed by the activities and participation component. International Classification of Functioning chapter and category distribution vary greatly between assessments and no assessment comprehensively examines community participation and relationships. The majority of the assessment items are of the health status-disability and quality of life perspectives. The results of this study suggest the need for the development of a comprehensive PAD assessment that includes a more even distribution of International Classification of Functioning topics and subtopics. A more comprehensive assessment would better capture the lived experience of this patient population. Implications for Rehabilitation A better understanding of the data collected using the current peripheral arterial disease-specific patient-reported outcome measures may contribute to the development of more comprehensive assessment tools that will ultimately lead to improved patient care. This study contributes to the preliminary foundation for the development of a peripheral arterial disease International Classification of Functioning, Disability and Health Core Set. Clinicians and researchers interested in using peripheral arterial disease

Four-dimensional echocardiography area strain combined with exercise stress echocardiography to evaluate left ventricular regional systolic function in patients with mild single vessel coronary artery stenosis.

Science.gov (United States)

Deng, Yan; Peng, Long; Liu, Yuan-Yuan; Yin, Li-Xue; Li, Chun-Mei; Wang, Yi; Rao, Li

2017-09-01

The aim of this prospective study was to assess the diagnosis value of four-dimensional echocardiography area strain (AS) combined with exercise stress echocardiography to evaluate left ventricular regional systolic function in patients with mild single vessel coronary artery stenosis. Based on treadmill exercise load status, two-dimensional conventional echocardiography and four-dimensional echocardiography area strain were performed on patients suspected coronary artery disease before coronary angiogram. Thirty patients (case group) with mild left anterior descending coronary artery stenosis (stenosis Four-dimensional echocardiography area strain combined with exercise stress echocardiography could sensitively find left ventricular regional systolic function abnormality in patients with mild single vessel coronary artery stenosis, and locate stenosis coronary artery accordingly. © 2017, Wiley Periodicals, Inc.

[Clinical, functional and biochemical characteristics of arterial hypertension in military men under chronic stress].

Science.gov (United States)

Shpagina, L A; Ermakova, M A; Volkova, E A; Iakovleva, S A

2008-01-01

Peculiarities of military occupational activities are repeated stress and high degree of psychoemotional strain. The article deals with results of momentary study covering a select from military men cohort, with thyroid tests, renal functional tests, diurnal monitoring of blood pressure and psychologic state assessment. Course of arterial hypertension in military men subjected to chronic stress presents prevailing systolic-diastolic and diastolic variants with excessive decrease of blood pressure at night, with high values of albuminuria. Psychologic state of the military men examined, whe were subjects to chronic stress, was mostly mixed reactivity type with general overstrain and somatization of inner conflict (psychosomatic variant of dysadaptation). The authors demonstrated close correlation between intrinsic emotional strain degree with arterial hypertension type according to "hyper-dipper" variant and free T3 level.

The Renal Arterial Resistance Index Predicts Worsening Renal Function in Chronic Heart Failure Patients

Science.gov (United States)

Iacoviello, Massimo; Monitillo, Francesco; Leone, Marta; Citarelli, Gaetano; Doronzo, Annalisa; Antoncecchi, Valeria; Puzzovivo, Agata; Rizzo, Caterina; Lattarulo, Maria Silvia; Massari, Francesco; Caldarola, Pasquale; Ciccone, Marco Matteo

2016-01-01

Background/Aim The renal arterial resistance index (RRI) is a Doppler measure, which reflects abnormalities in the renal blood flow. The aim of this study was to verify the value of RRI as a predictor of worsening renal function (WRF) in a group of chronic heart failure (CHF) outpatients. Methods We enrolled 266 patients in stable clinical conditions and on conventional therapy. Peak systolic velocity and end diastolic velocity of a segmental renal artery were obtained by pulsed Doppler flow, and RRI was calculated. Creatinine serum levels were evaluated at baseline and at 1 year, and the changes were used to assess WRF occurrence. Results During follow-up, 34 (13%) patients showed WRF. RRI was associated with WRF at univariate (OR: 1.13; 95% CI: 1.07–1.20) as well as at a forward stepwise multivariate logistic regression analysis (OR: 1.09; 95% CI: 1.03–1.16; p = 0.005) including the other univariate predictors. Conclusions Quantification of arterial renal perfusion provides a new parameter that independently predicts the WRF in CHF outpatients. Its possible role in current clinical practice to better define the risk of cardiorenal syndrome progression is strengthened. PMID:27994601

Subarachnoid hemorrhage enhances endothelin receptor expression and function in rat cerebral arteries

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Hansen-Schwartz, Jacob; Hoel, Natalie Løvland; Zhou, Mingfang

2003-01-01

OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood into the prechiasm......OBJECTIVE: Inspired by organ culture-induced changes in the vascular endothelin (ET) receptor population, we investigated whether such changes occur in cerebral arteries in a rat subarachnoid hemorrhage (SAH) model. METHODS: SAH was induced with injection of 250 microl of blood...... into the prechiasmatic cistern. After 2 days, the middle cerebral artery, basilar artery, and posterior communicating artery were harvested. Pharmacological studies were performed in vitro, and levels of messenger ribonucleic acid (mRNA) were quantified in real-time reverse transcriptase-polymerase chain reaction assays....... RESULTS: In the middle cerebral artery and basilar artery from rats with induced SAH, enhanced biphasic responses to ET-1 were observed. The -log(50% effective concentration) value for the high-affinity phase was approximately 12, compared with approximately 8.5 for sham-operated animals...

Mean pressure of pulmonary arteries in non-callous silicosis at states 1 to 2 as determined by radiology in comparison to parameters of pulmonary function

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Jakob, M; Konrad, A; Adam, P; Scharf, R

1984-11-19

Fifty coal miners suffering from reticulonodular silicosis underwent catheterization of the right heart and showed latent or manifest pulmonary hypertension. It has been found that the statistical relationship between pulmonary arterial pressure and pulmonary function was only a loose one. Thirty percent of the studied subjects presented no alterations of the lung function but an increased pulmonary artery mean pressure at rest and under exercise, indicating that the Euler-Liljestrand-mechanism could hardly be responsible for these pressure changes. Subjects with silicosis who presented impaired lung function showed statistically significant higher pulmonary artery pressures than those without alteration of the lung function. It is likely that an additional pressure increase occurs secondary to Euler-Liljestrand-mechanism, when restrictive or obstructive impairments of ventilation emerge from the pneumoconiosis.

Protective effects of simvastatin on coronary artery function in swine with acute infection

DEFF Research Database (Denmark)

Liuba, Petru; Pesonen, Erkki; Forslid, Anders

2006-01-01

cholesterol) between the groups (p>0.2). CONCLUSION:: Acute infection is associated with impairment of the muscarinic and kinin-related reactivity of coronary circulation. These functional abnormalities are in part prevented by simvastatin through mechanisms unrelated to lipid lowering......BACKGROUND:: The risk for coronary events may rise during acute infection. Perturbation in coronary endothelial function emerges as one important link. We investigated whether simvastatin could protect the coronary arterial function from the adverse effects of acute infection in swine. METHODS......:: Coronary endothelium-dependent and -independent vasomotor responses were assessed by Doppler velocimetry in 12 Chlamydia pneumoniae-infected and 6 sham-infected swine 2 weeks after intratracheal inoculation. Half of animals from the infection group were pre-treated with simvastatin (80mg daily), while...

Arterial Injury and Endothelial Repair: Rapid Recovery of Function after Mechanical Injury in Healthy Volunteers

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Lindsey Tilling

2014-01-01

Full Text Available Objective. Previous studies suggest a protracted course of recovery after mechanical endothelial injury; confounders may include degree of injury and concomitant endothelial dysfunction. We sought to define the time course of endothelial function recovery using flow-mediated dilation (FMD, after ischaemia-reperfusion (IR and mechanical injury in patients and healthy volunteers. The contribution of circulating CD133+/CD34+/VEGFR2+ “endothelial progenitor” (EPC or repair cells to endothelial repair was also examined. Methods. 28 healthy volunteers aged 18–35 years underwent transient forearm ischaemia induced by cuff inflation around the proximal biceps and radial artery mechanical injury induced by inserting a wire through a cannula. A more severe mechanical injury was induced using an arterial sheath and catheter inserted into the radial artery of 18 patients undergoing angiography. Results. IR and mechanical injury produced immediate impairment of FMD (from 6.5 ± 1.2% to 2.9 ± 2.2% and from 7.4 ± 2.3% to 1.5 ± 1.6% for IR and injury, resp., each P<0.001 but recovered within 6 hours and 2 days, respectively. FMD took up to 4 months to recover in patients. Circulating EPC did not change significantly during the injury/recovery period in all subjects. Conclusions. Recovery of endothelial function after IR and mechanical injury is rapid and not associated with a change in circulating EPC.

Role of the autonomic nervous system and baroreflex in stress-evoked cardiovascular responses in rats.

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Dos Reis, Daniel Gustavo; Fortaleza, Eduardo Albino Trindade; Tavares, Rodrigo Fiacadori; Corrêa, Fernando Morgan Aguiar

2014-07-01

Restraint stress (RS) is an experimental model to study stress-related cardiovascular responses, characterized by sustained pressor and tachycardiac responses. We used pharmacologic and surgical procedures to investigate the role played by sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS) in the mediation of stress-evoked cardiovascular responses. Ganglionic blockade with pentolinium significantly reduced RS-evoked pressor and tachycardiac responses. Intravenous treatment with homatropine methyl bromide did not affect the pressor response but increased tachycardia. Pretreatment with prazosin reduced the pressor and increased the tachycardiac response. Pretreatment with atenolol did not affect the pressor response but reduced tachycardia. The combined treatment with atenolol and prazosin reduced both pressor and tachycardiac responses. Adrenal demedullation reduced the pressor response without affecting tachycardia. Sinoaortic denervation increased pressor and tachycardiac responses. The results indicate that: (1) the RS-evoked cardiovascular response is mediated by the autonomic nervous system without an important involvement of humoral factors; (2) hypertension results primarily from sympathovascular and sympathoadrenal activation, without a significant involvement of the cardiac sympathetic component (CSNS); (3) the abrupt initial peak in the hypertensive response to restraint is sympathovascular-mediated, whereas the less intense but sustained hypertensive response observed throughout the remaining restraint session is mainly mediated by sympathoadrenal activation and epinephrine release; (4) tachycardia results from CSNS activation, and not from PSNS inhibition; (5) RS evokes simultaneous CSNS and PSNS activation, and heart rate changes are a vector of both influences; (6) the baroreflex is functional during restraint, and modulates both the vascular and cardiac responses to restraint.

Impaired Arterial Smooth Muscle Cell Vasodilatory Function In Methamphetamine Users

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Ghaemeh Nabaei

2017-02-01

Full Text Available Objectives: Methamphetamine use is a strong risk factor for stroke. This study was designed to evaluate arterial function and structure in methamphetamine users ultrasonographically. Methods: In a cross-sectional study, 20 methamphetamine users and 21 controls, aged between 20 and 40years, were enrolled. Common carotid artery intima-media thickness (CCA-IMT marker of early atherogenesis, flow-mediated dilatation (FMD determinants of endothelium-dependent vasodilation, and nitroglycerine-mediated dilatation (NMD independent marker of vasodilation were measured in two groups. Results: There were no significant differences between the two groups regarding demographic and metabolic characteristics. The mean (±SD CCA-IMT in methamphetamine users was 0.58±0.09mm, versus 0.59±0.07mm in the controls (p=0.84. Likewise, FMD% was not significantly different between the two groups [7.6±6.1% in methamphetamine users vs. 8.2±5.1% in the controls; p=0.72], nor were peak flow and shear rate after hyperemia. However, NMD% was considerably decreased in the methamphetamine users [8.5±7.8% in methamphetamine users vs. 13.4±6.2% in controls; p=0.03]. Conclusion: According to our results, NMD is reduced among otherwise healthy methamphetamine users, which represents smooth muscle dysfunction in this group. This may contribute to the high risk of stroke among methamphetamine users.

A comparison of long-term functional outcome after 2 middle cerebral artery occlusion models in rats.

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Roof, R L; Schielke, G P; Ren, X; Hall, E D

2001-11-01

Proven behavioral assessment strategies for testing potential therapeutic agents in rat stroke models are needed. Few studies include tasks that demand higher levels of sensorimotor and cognitive function. Because behavioral outcome and rate of recovery vary among ischemia models, there is a need to characterize and compare performance on specific tasks across models. To this end, sensorimotor and cognitive deficits were assessed during a 5-week period after either permanent proximal middle cerebral artery occlusion (pMCAO) or permanent distal middle cerebral artery occlusion combined with a 90-minute occlusion of both common carotid arteries (dMCAO/tCCAO) in Sprague-Dawley rats. The EBST, hindlimb and forelimb placing, and cylinder tests were given at regular intervals postinjury to assess sensorimotor function. Cognitive function was assessed with a multitrial water navigation task. pMCAO, which caused both striatal and cortical damage, produced persistent sensorimotor and cognitive deficits. Limb placing responses and postural reflexes were impaired throughout the month of testing. A persistent bias for using the ipsilateral forelimb for wall movements in the cylinder test was observed as well as a bias for landing on the opposite forelimb. pMCAO rats were also impaired in the water navigation task. dMCAO/tCCAO, which caused only cortical damage, produced similar sensorimotor deficits, but these were greatly diminished by 2 weeks after injury. No impairment was found for water tank navigation. Correlations between forelimb placing (both models), water navigation performance (pMCAO model), and sensorimotor asymmetry (dMCAOtCCAO model) and infarct volume were observed. Based on the range of functions affected and stability of observed deficits, the pMCAO model appears to be preferable to the dMCAO/tCCAO model for use in assessing therapeutic agents for stroke.

Arterial stiffness

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Ursula Quinn

2012-09-01

Full Text Available Measurements of biomechanical properties of arteries have become an important surrogate outcome used in epidemiological and interventional cardiovascular research. Structural and functional differences of vessels in the arterial tree result in a dampening of pulsatility and smoothing of blood flow as it progresses to capillary level. A loss of arterial elastic properties results a range of linked pathophysiological changes within the circulation including increased pulse pressure, left ventricular hypertrophy, subendocardial ischaemia, vessel endothelial dysfunction and cardiac fibrosis. With increased arterial stiffness, the microvasculature of brain and kidneys are exposed to wider pressure fluctuations and may lead to increased risk of stroke and renal failure. Stiffening of the aorta, as measured by the gold-standard technique of aortic Pulse Wave Velocity (aPWV, is independently associated with adverse cardiovascular outcomes across many different patient groups and in the general population. Therefore, use of aPWV has been proposed for early detection of vascular damage and individual cardiovascular risk evaluation and it seems certain that measurement of arterial stiffness will become increasingly important in future clinical care. In this review we will consider some of the pathophysiological processes that result from arterial stiffening, how it is measured and factors that may drive it as well as potential avenues for therapy. In the face of an ageing population where mortality from atheromatous cardiovascular disease is falling, pathology associated with arterial stiffening will assume ever greater importance. Therefore, understanding these concepts for all clinicians involved in care of patients with cardiovascular disease will become vital.

Changes in endothelial function, arterial stiffness and blood pressure in pregnant women after consumption of high-flavanol and high-theobromine chocolate: a double blind randomized clinical trial.

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Babar, Asma; Bujold, Emmanuel; Leblanc, Vicky; Lavoie-Lebel, Élise; Paquette, Joalee; Bazinet, Laurent; Lemieux, Simone; Marc, Isabelle; Abdous, Belkacem; Dodin, Sylvie

2018-04-16

The aim of this 2-group, parallel, double blind single-centre RCT was to evaluate the acute and chronic impacts of high flavanol high theobromine (HFHT) chocolate consumption on endothelial function, arterial stiffness and blood pressure (BP) in women at risk of preeclampsia. 131 pregnant women considered at risk of preeclampsia based on uterine artery Doppler ultrasound were divided into two groups (HFHT or low flavanol and theobromine chocolate (LFLT). Acute changes in plasma flavanol and theobromine, peripheral arterial tonometry and BP were evaluated at randomization (0, 60 and 120 min after a single 40-g dose of chocolate) and again 6 and 12 weeks after daily 30-g chocolate intake. The EndoPAT 2000 provided reactive hyperemia index (RHI) and adjusted augmentation index (AIx) as markers for endothelial function and arterial stiffness, respectively. Compared with LFLT, acute HFHT intake significantly increased plasma epicatechin and theobromine (p theobromine (p theobromine concentrations and decreased arterial stiffness, with no effect on endothelial function and a marginal increase in diastolic BP. Chronic HFHT intake increased plasma theobromine, though it did not have positive impacts on endothelial function, arterial stiffness or BP when compared to LFLT in pregnant women at risk of PE.

A quantitative method for studying human arterial baroreflexes

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Eckberg, Dwain L.; Fritsch, Janice M.; Goble, Ross L.

1991-01-01

A new system is described that delivers precise, stereotyped pressure changes to the human neck and elicits neurally-mediated heart rate changes. The centerpiece of this system is a Silastic chamber that is strapped to the anterior neck. This chamber is connected to a stepping-motor-controlled bellows assembly. A strain-gauge transducer measures the intensity of pressure changes. The entire system is controlled by microprocessors, and both stimuli and responses are displayed on a digital oscilloscope. The end-product of this system is a reproducible baroreceptor stimulus-cardiac response relation that can be recorded rapidly and safely in astronauts in space.

Semi-parametric arterial input functions for quantitative dynamic contrast enhanced magnetic resonance imaging in mice

Czech Academy of Sciences Publication Activity Database

Taxt, T.; Reed, R. K.; Pavlin, T.; Rygh, C. B.; Andersen, E.; Jiřík, Radovan

2018-01-01

Roč. 46, FEB (2018), s. 10-20 ISSN 0730-725X R&D Projects: GA ČR GA17-13830S; GA MŠk(CZ) LO1212 Institutional support: RVO:68081731 Keywords : DCE-MRI * blind deconvolution * arterial input function Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.225, year: 2016

Influence of orlistat therapy on serum insulin level and morphological and functional parameters of peripheral arterial circulation in obese patients

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Hajduković Zoran

2005-01-01

Full Text Available Background/Aim. Insulin resistance is related to accelerated atherosclerosis, whereas weight loss is associated with the increasing insulin sensitivity, the improvement of functional and the morphological parameters of arterial circulation, and the reduction of cardiovascular morbidity and mortality. The aim of our study was to evaluate the influence of orlistat treatment on serum insulin level and functional and morphologic parameters of peripheral arterial circulation. Methods. We conducted a prospective, randomized, double − blind, placebo − controlled study. Thirty patients with body mass index over 30 kg/m2 normotensive, nonsmokers, without clinically manifested cardiovascular disease or diabetes were randomly assigned either orlistat (120 mg, 3 times daily; n = 20 or placebo (n = 10 in a double − blind manner. All of the patients were on individually calculated hypocaloric diet. The follow-up period was 24 weeks. Arterial pressure, fasting serum glucose and insulin level, triglycerides, total cholesterol and low density lipoprotein-cholesterol were determined at the beginning, following 3 and 6 months. Also, the intima − media thickness of right superficial femoral artery and the mean blood flow velocity were determined with ultrasonography. Results. Inside the period of 3 and 6 months, there were the greater reductions of body mass index, arterial pressure, fasting glucose and insulin level, total cholesterol, low density lipoproteins, as well as the greater reductions of mean velocity blood flow and peripheral pulse pressure in the orlistat group vs the placebo group (p < 0.01. Greater reductions in the waist circumference and intima − media thickness were registered following 6 months in the orlistat vs the placebo group (p < 0.01. Conclusion. In the group of obese patients orlistat therapy reduced risk factors, serum insulin level and improved early arterial functional changes as assessed with the reductions of the mean

Autonomic control of the heart is altered in Sprague-Dawley rats with spontaneous hydronephrosis

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Arnold, Amy C.; Shaltout, Hossam A.; Gilliam-Davis, Shea; Kock, Nancy D.

2011-01-01

The renal medulla plays an important role in cardiovascular regulation, through interactions with the autonomic nervous system. Hydronephrosis is characterized by substantial loss of renal medullary tissue. However, whether alterations in autonomic control of the heart are observed in this condition is unknown. Thus we assessed resting hemodynamics and baroreflex sensitivity (BRS) for control of heart rate in urethane/chloralose-anesthetized Sprague-Dawley rats with normal or hydronephrotic kidneys. While resting arterial pressure was similar, heart rate was higher in rats with hydronephrosis (290 ± 12 normal vs. 344 ± 11 mild/moderate vs. 355 ± 13 beats/min severe; P hydronephrosis, with no differences in measures of indirect sympathetic activity among conditions. As a secondary aim, we investigated whether autonomic dysfunction in hydronephrosis is associated with activation of the renin-angiotensin system (RAS). There were no differences in circulating angiotensin peptides among conditions, suggesting that the impaired autonomic function in hydronephrosis is independent of peripheral RAS activation. A possible site for angiotensin II-mediated BRS impairment is the solitary tract nucleus (NTS). In normal and mild/moderate hydronephrotic rats, NTS administration of the angiotensin II type 1 receptor antagonist candesartan significantly improved the BRS, suggesting that angiotensin II provides tonic suppression to the baroreflex. In contrast, angiotensin II blockade produced no significant effect in severe hydronephrosis, indicating that at least within the NTS baroreflex suppression in these animals is independent of angiotensin II. PMID:21460193

Relationship of cerebral arterial stenosis to cognitive and memory disorders

Institute of Scientific and Technical Information of China (English)

Jifeng Li; Zhou Wang; Shenggang Sun; Gaomei Cai; Kejin Gu; Yaoqun Li

2006-01-01

BACKGROUND: Cerebral arterial stenosis can cause cerebral hypoperfusion, and than result in the decline of cognitive function, whereas the cognitive dysfunction induced by different cerebral arterial stenosis have different manifestations and types.OBJECTIVE: To observe the differences of cognitive and memory dysfunctions in patients with cerebral arterial stenosis of different types.DESIGN: A comparative observation.SETTING: Affiliated Hospital of Jining Medical College.PARTICIPANTS: Forty-two outpatients or inpatients with cerebral arterial stenosis were selected from the Department of Neurology, Affiliated Hospital of Jining Medical College from February 2005 to January 2006,including 25 males and 17 females. There were 18 cases of internal carotid arterial stenosis, 14 cases of vertebrobasilar arterial stenosis and 10 cases of whole cerebral arterial stenosis. The diagnostic standards for cerebral arterial stenosis were identified according to North American Symptomatic Carotid Endarterectomy Trial (NAS CET). Meanwhile, 18 healthy physical examinees were enrolled as the control group, including 10males and 8 females, aged 58-80 years old. All the enrolled subjects were informed and agreed with the detection and evaluation.METHODS: ① The memory function was evaluated using revised Wechsler memory scale for adults, including long-term memory (experience, orientation and counting), short-term memory (visual recognition, picture memory, visual regeneration, association and thigmesthesia) and sensory memory (forward and backward recitation of numbers). The scale scores were turned to memory quotients. The higher the scores, the better the memory function. ② The cognitive function was evaluated using revised Wechsler adult intelligence scale:It consisted of eleven subtests, including six language scales (information, digit span, vocabulary, arithmetics,apprehension, similarity) and five operation scales (picture completion, picture arrangement, block design

Evaluation of functional severity of coronary artery disease and fluid dynamics' influence on hemodynamic parameters: A review.

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Govindaraju, Kalimuthu; Badruddin, Irfan Anjum; Viswanathan, Girish N; Ramesh, S V; Badarudin, A

2013-05-01

Coronary Artery Disease (CAD) is responsible for most of the deaths in patients with cardiovascular diseases. Diagnostic coronary angiography analysis offers an anatomical knowledge of the severity of the stenosis. The functional or physiological significance is more valuable than the anatomical significance of CAD. Clinicians assess the functional severity of the stenosis by resorting to an invasive measurement of the pressure drop and flow. Hemodynamic parameters, such as pressure wire assessment fractional flow reserve (FFR) or Doppler wire assessment coronary flow reserve (CFR) are well-proven techniques to evaluate the physiological significance of the coronary artery stenosis in the cardiac catheterization laboratory. Between the two techniques mentioned above, the FFR is seen as a very useful index. The presence of guide wire reduces the coronary flow which causes the underestimation of pressure drop across the stenosis which leads to dilemma for the clinicians in the assessment of moderate stenosis. In such condition, the fundamental fluid mechanics is useful in the development of new functional severity parameters such as pressure drop coefficient and lesion flow coefficient. Since the flow takes place in a narrowed artery, the blood behaves as a non-Newtonian fluid. Computational fluid dynamics (CFD) allows a complete coronary flow simulation to study the relationship between the pressure and flow. This paper aims at explaining (i) diagnostic modalities for the evaluation of the CAD and valuable insights regarding FFR in the evaluation of the functional severity of the CAD (ii) the role of fluid dynamics in measuring the severity of CAD. Copyright © 2012 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Late Posthemorrhagic Structural and Functional Changes in Pulmonary Circulation Arteries

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S. A. Andreyeva

2008-01-01

Full Text Available Objective: to reveal the major regularities and mechanisms of morphological changes in the rat pulmonary circulation arteries in the late posthemorrhagic period and to compare them with age-related features of the vessels. Materials and methods: experiments to generate graduated hemorrhagic hypotension with the blood pressure being maintained at 40 mm Hg were carried out on young (5—6-month albino male Wistar rats. Throughout hypotension and 60 days after blood loss, the blood was tested to determine low and average molecular-weight substances by spectrophotometry and the pro- and antioxidative systems by chemiluminescence. Pulmonary circulation arteries were morphologically studied in young animals, rats in the late posthemorrhagic period and old (24—25-month rats. Results. Sixty-minute hemorrhagic hypotension leads to the development of endotoxemia and imbalance of the pro- and antioxidative systems, the signs of which are observed in the late periods (2 months after hypotension. At the same time, the posthemorrhagic period is marked by the significant pulmonary circulation arterial morphological changes comparable with their age-related alterations in old rat. This shows up mainly in the reorganization of a connective tissue component in the vascular wall: the elevated levels of individual collagen fibers, their structural changes, elastic medial membrane destruction and deformity. At the same time, there is a change in the morphometric parameters of vessels at all study stages while their lowered flow capacity is only characteristic for intraorgan arteries. Conclusion: The increased activity of free radical oxidation and endotoxemia may be believed to be one of the causes of morphological changes in pulmonary circulation arteries in the late posthemorrhagic period, which is similar to age-related vascular alterations. Key words: hemorrhagic hypotension, pulmonary circulation arteries, free radical oxidation, endotoxemia, remodeling, late

Characterizing Resting-State Brain Function Using Arterial Spin Labeling

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Jann, Kay; Wang, Danny J.J.

2015-01-01

Abstract Arterial spin labeling (ASL) is an increasingly established magnetic resonance imaging (MRI) technique that is finding broader applications in studying the healthy and diseased brain. This review addresses the use of ASL to assess brain function in the resting state. Following a brief technical description, we discuss the use of ASL in the following main categories: (1) resting-state functional connectivity (FC) measurement: the use of ASL-based cerebral blood flow (CBF) measurements as an alternative to the blood oxygen level-dependent (BOLD) technique to assess resting-state FC; (2) the link between network CBF and FC measurements: the use of network CBF as a surrogate of the metabolic activity within corresponding networks; and (3) the study of resting-state dynamic CBF-BOLD coupling and cerebral metabolism: the use of dynamic CBF information obtained using ASL to assess dynamic CBF-BOLD coupling and oxidative metabolism in the resting state. In addition, we summarize some future challenges and interesting research directions for ASL, including slice-accelerated (multiband) imaging as well as the effects of motion and other physiological confounds on perfusion-based FC measurement. In summary, this work reviews the state-of-the-art of ASL and establishes it as an increasingly viable MRI technique with high translational value in studying resting-state brain function. PMID:26106930

Structural and Functional Coronary Artery Abnormalities in Patients With Vasospastic Angina Pectoris

DEFF Research Database (Denmark)

Ong, Peter; Aziz, Ahmed; Hansen, Henrik Steen

2015-01-01

Coronary spasm is involved in many clinical scenarios, such as stable angina, acute coronary syndrome, sudden cardiac death, non-ischemic cardiomyopathy, arrhythmia and syncope. In recent years, imaging tools such as computerized tomographic angiography, intravascular ultrasound or optical...... coherence tomography have been applied to study the coronary pathology in patients with vasospastic angina. Patients with vasospastic angina represent a heterogeneous cohort of patients with regard to the extent of concomitant coronary atherosclerosis. They share the common pathophysiological phenomenon...... of this article is to review structural and functional coronary artery abnormalities in patients with vasospastic angina....

Impaired cerebrovascular function in coronary artery disease patients and recovery following cardiac rehabilitation.

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Udunna C Anazodo

2016-01-01

Full Text Available Coronary artery disease (CAD poses a risk to the cerebrovascular function of older adults and has been linked to impaired cognitive abilities. Using magnetic resonance perfusion imaging, we investigated changes in resting cerebral blood flow (CBF and cerebrovascular reactivity (CVR to hypercapnia in 34 coronary artery disease (CAD patients and 21 age-matched controls. Gray matter volume images were acquired and used as a confounding variable to separate changes in structure from function. Compared to healthy controls, CAD patients demonstrated reduced CBF in the superior frontal, anterior cingulate, insular, pre- and post-central gyri, middle temporal and superior temporal regions. Subsequent analysis of these regions demonstrated decreased CVR in the anterior cingulate, insula, postcentral and superior frontal regions. Except in the superior frontal and precentral regions, regional reductions in CBF and CVR were identified in brain areas where no detectable reductions in gray matter volume were observed, demonstrating that these vascular changes were independent of brain atrophy. Because aerobic fitness training can improve brain function, potential changes in regional CBF were investigated in the CAD patients after completion of a 6-month exercise-based cardiac rehabilitation program. Increased CBF was observed in the bilateral anterior cingulate, as well as recovery of CBF in the dorsal aspect of the right anterior cingulate, where the magnitude of increased CBF was roughly equal to the reduction in CBF at baseline compared to controls. These exercise-related improvements in CBF in the anterior cingulate is intriguing given the role of this area in cognitive processing and regulation of cardiovascular autonomic control.

[Ultrastructure of the intima of human pial arteries in arterial hypertension].

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Chertok, V M; Kotsiuba, A E; Babich, E V

2009-01-01

Ultrastructure of the intima of human pial arteries obtained from 5 male cadavers of practically healthy individuals and from 8 cadavers of the patients with the intravitally diagnosed grade I arterial hypertension (AH) was studied by scanning and transmission electron microscopy. AH was found to be associated with the remodeling of the intimal structural elements in the pial arteries. In most arteries, the changes were detected in the microrelief of the luminal surface and in the permeability of the vascular endothelial lining and of the subendothelial layer. During this remodeling, some endothelial cells were found in the state of structural and functional adaptation to the elevated arterial pressure, while the others were undergoing the dystrophic changes. The latter include the cells containing lipid inclusions, as well as the endothelial cells presumably in the state of apoptosis. The destruction of the intercellular junctions, the disturbances in the endothelium permeability contributed to the development of subendothelial layer edema, resulting in its significant thickening. This layer became looser and contained abundant collagen fibrils.

Functional assessment of the hepatic arterial blood flow by pharmacoradiography

Energy Technology Data Exchange (ETDEWEB)

Stellamor, K; Hruby, W; Peschl, L

1981-12-01

By means of celiacography it was possible to demonstrate that parenteral medication with parathormone creates a selective dilatation of the liver vessels in man, provided that they are dilatable. This hemodynamic hormone effect could not be traced in the other mesenteric vessels. The increase of portal hypertension resulting from cirrhosis leads to a loss of the dilating ability of liver vessels. This regressive reaction is well demonstrated on the parathormone-celiacogram. Thus a functional assessment of the hepatic blood flow is possible. The extent of the dilatability of the liver artery seems to be of great importance for the prognosis and indication of the porto-systemic shunt-operation. Moreover we could show that an increase in the liver perfusion demonstrates pathologic liver processes in a better way.

High-NaCl diet impairs dynamic renal blood flow autoregulation in rats with adenine-induced chronic renal failure

DEFF Research Database (Denmark)

Saeed, Aso; DiBona, Gerald F; Grimberg, Elisabeth

2014-01-01

This study examined the effects of 2 wk of high-NaCl diet on kidney function and dynamic renal blood flow autoregulation (RBFA) in rats with adenine-induced chronic renal failure (ACRF). Male Sprague-Dawley rats received either chow containing adenine or were pair-fed an identical diet without...... arterial pressure variability (SAPV), and heart rate variability were assessed by spectral analytical techniques. Rats with ACRF showed marked reductions in glomerular filtration rate and renal blood flow (RBF), whereas mean arterial pressure and SAPV were significantly elevated. In addition, spontaneous...... adenine (controls). After 10 wk, rats were randomized to either remain on the same diet (0.6% NaCl) or to be switched to high 4% NaCl chow. Two weeks after randomization, renal clearance experiments were performed under isoflurane anesthesia and dynamic RBFA, baroreflex sensitivity (BRS), systolic...

The Effect of Elective Percutaneous Coronary Intervention of the Right Coronary Artery on Right Ventricular Function

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Farahnaz Nikdoust

2014-12-01

Full Text Available Background: Right Ventricular (RV dysfunction has been introduced as a predictor of mortality in acute myocardial infarction. Objectives: This study aimed to investigate the effect of right coronary revascularization on systolic and diastolic RV dysfunction. Patients and Methods: This study was conducted on unstable angina patients who were candidate for elective Percutaneous Revascularization Intervention (PCI on the right coronary artery. The participants were initially evaluated by transthoracic echocardiography and tissue Doppler imaging prior to PCI and the RV function parameters were assessed. Echocardiography was repeated two months after PCI and the results were compared with baseline. Paired t-test was used to compare the pre- and post-procedural measurements. Besides, Pearson’s correlation was used to find out the linear association between the RV function parameters and Left Ventricular Ejection Fraction (LVEF. P value < 0.05 was considered as statistically significant. Results: This study was conducted on 30 patients (mean age = 60.00 ± 8.44 years; 24 [80%] males. In the pre-procedural echocardiography, 15 patients (50% had normal RV function, 14 patients (46.7% had grade-1 RV dysfunction, and only 1 patient (3.3% had grade-2 RV dysfunction. Following PCI, however, all the patients had normal systolic and diastolic RV functions. Comparison of echocardiographic RV function parameters showed an improvement in both systolic and diastolic functional parameters of the RV. Nonetheless, no significant correlation was observed between these parameters and Left Ventricular (LV function. Conclusions:: A significant improvement was found in RV function, but not LV function, after right coronary PCI. Revascularization of the right coronary artery may be beneficial for the patients who suffer from RV failure due to ischemia

Sympathetic Innervation Promotes Arterial Fate by Enhancing Endothelial ERK Activity.

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Pardanaud, Luc; Pibouin-Fragner, Laurence; Dubrac, Alexandre; Mathivet, Thomas; English, Isabel; Brunet, Isabelle; Simons, Michael; Eichmann, Anne

2016-08-19

Arterial endothelial cells are morphologically, functionally, and molecularly distinct from those found in veins and lymphatic vessels. How arterial fate is acquired during development and maintained in adult vessels is incompletely understood. We set out to identify factors that promote arterial endothelial cell fate in vivo. We developed a functional assay, allowing us to monitor and manipulate arterial fate in vivo, using arteries isolated from quails that are grafted into the coelom of chick embryos. Endothelial cells migrate out from the grafted artery, and their colonization of host arteries and veins is quantified. Here we show that sympathetic innervation promotes arterial endothelial cell fate in vivo. Removal of sympathetic nerves decreases arterial fate and leads to colonization of veins, whereas exposure to sympathetic nerves or norepinephrine imposes arterial fate. Mechanistically, sympathetic nerves increase endothelial ERK (extracellular signal-regulated kinase) activity via adrenergic α1 and α2 receptors. These findings show that sympathetic innervation promotes arterial endothelial fate and may lead to novel approaches to improve arterialization in human disease. © 2016 American Heart Association, Inc.

A randomised trial comparing the effect of exercise training and weight loss on microvascular function in coronary artery disease

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Olsen, Rasmus Huan; Pedersen, Lene Rørholm; Jürs, Anders

2015-01-01

BACKGROUND: Coronary microvascular function is associated with outcome and is reduced in coronary artery disease (CAD) and obesity. We compared the effect of aerobic interval training (AIT) and weight loss on coronary flow reserve (CFR) and peripheral vascular function in revascularised obese CAD...... patients. METHODS AND RESULTS: Seventy non-diabetic patients (BMI 28-40 kg × m(-2), age 45-75 years) were randomised to 12 weeks' AIT (three weekly sessions lasting 38 min with ≈ 16 min at 85-90% of VO2peak) or low energy diet (LED, 800-1000 kcal/day). Per protocol adherence was defined by training......-attendance ≥ 60% and weight loss ≥ 5%, respectively. CFR was assessed by Doppler echocardiography of the LAD. Peripheral vascular function was assessed by arterial tonometry as reactive hyperaemia index (RHI) and augmentation index. Most participants had impaired CFR with a mean CFR of 2.38 (SD 0.59). Twenty...

Effects of Clopidogrel Therapy on Oxidative Stress, Inflammation, Vascular Function and Progenitor Cells in Stable Coronary Artery Disease

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Ramadan, Ronnie; Dhawan, Saurabh S.; Syed, Hamid; Pohlel, F. Khan; Binongo, Jose Nilo G.; Ghazzal, Ziyad B.; Quyyumi, Arshed A.

2014-01-01

Background Traditional cardiovascular risk factors lead to endothelial injury and activation of leucocytes and platelets that initiate and propagate atherosclerosis. We proposed that clopidogrel therapy in patients with stable CAD imparts a pleiotropic effect that extends beyond anti-platelet aggregation to other athero-protective processes. Methods Forty-one subjects were randomized in a double-blind, placebo-controlled crossover study to either clopidogrel 75 mg daily or placebo for 6-weeks, and then transitioned immediately to the other treatment for an additional 6 weeks. We assessed 1) endothelial function as flow-mediated dilation of the brachial artery, 2) arterial stiffness and central augmentation index using applanation tonometry, 3) vascular function as fingertip reactive hyperemia index, 4) inflammation by measuring plasma CD40 ligand and serum high-sensitivity c-reactive protein levels, 5) oxidative stress by measuring plasma aminothiols, and 6) circulating progenitor cells, at baseline and at the end of each 6-week treatment period. Results Clopidogrel therapy resulted in a significant reduction in soluble CD40 ligand (p=0.03), a pro-thrombotic and pro-inflammatory molecule derived mainly from activated platelets. However, clopidogrel therapy had no effect on endothelial function, arterial stiffness, inflammatory and oxidative stress markers, or progenitor cells. Conclusions Our findings suggest a solitary anti-platelet effect of clopidogrel therapy in patients with stable CAD, with no effect on other sub-clinical markers of cardiovascular disease risk. PMID:24336012

The future of collateral artery research

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Hakimzadeh, Nazanin; Verberne, Hein J.; Siebes, Maria; Piek, Jan J.

2014-01-01

In the event of obstructive coronary artery disease, collateral arteries have been deemed an alternative blood source to preserve myocardial tissue perfusion and function. Monocytes play an important role in modulating this process, by local secretion of growth factors and extracellular matrix

Cardiovascular risk factors and collateral artery formation.

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de Groot, D; Pasterkamp, G; Hoefer, I E

2009-12-01

Arterial lumen narrowing and vascular occlusion is the actual cause of morbidity and mortality in atherosclerotic disease. Collateral artery formation (arteriogenesis) refers to an active remodelling of non-functional vascular anastomoses to functional collateral arteries, capable to bypass the site of obstruction and preserve the tissue that is jeopardized by ischaemia. Hemodynamic forces such as shear stress and wall stress play a pivotal role in collateral artery formation, accompanied by the expression of various cytokines and invasion of circulating leucocytes. Arteriogenesis hence represents an important compensatory mechanism for atherosclerotic vessel occlusion. As arteriogenesis mostly occurs when lumen narrowing by atherosclerotic plaques takes place, presence of cardiovascular risk factors (e.g. hypertension, hypercholesterolaemia and diabetes) is highly likely. Risk factors for atherosclerotic disease affect collateral artery growth directly and indirectly by altering hemodynamic forces or influencing cellular function and proliferation. Adequate collateralization varies significantly among atherosclerotic patients, some profit from the presence of extensive collateral networks, whereas others do not. Cardiovascular risk factors could increase the risk of adverse cardiovascular events in certain patients because of the reduced protection through an alternative vascular network. Likewise, drugs primarily thought to control cardiovascular risk factors might contribute or counteract collateral artery growth. This review summarizes current knowledge on the influence of cardiovascular risk factors and the effects of cardiovascular medication on the development of collateral vessels in experimental and clinical studies.

Purple grape juice improves endothelial function and reduces the susceptibility of LDL cholesterol to oxidation in patients with coronary artery disease.

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Stein, J H; Keevil, J G; Wiebe, D A; Aeschlimann, S; Folts, J D

1999-09-07

In vitro, the flavonoid components of red wine and purple grape juice are powerful antioxidants that induce endothelium-dependent vasodilation of vascular rings derived from rat aortas and human coronary arteries. Although improved endothelial function and inhibition of LDL oxidation may be potential mechanisms by which red wine and flavonoids reduce cardiovascular risk, the in vivo effects of grape products on endothelial function and LDL oxidation have not been investigated. This study assessed the effects of ingesting purple grape juice on endothelial function and LDL susceptibility to oxidation in patients with coronary artery disease (CAD). Fifteen adults with angiographically documented CAD ingested 7.7+/-1.2 mL. kg(-1). d(-1) of purple grape juice for 14 days. Flow-mediated vasodilation (FMD) was measured using high-resolution brachial artery ultrasonography. Susceptibility of LDL particles to oxidation was determined from the rate of conjugated diene formation after exposure to copper chloride. At baseline, FMD was impaired (2.2+/-2. 9%). After ingestion of grape juice, FMD increased to 6.4+/-4.7% (P=0.003). In a linear regression model that included age, artery diameter, lipid values, and use of lipid-lowering and antioxidant therapies, the effect of grape juice on FMD remained significant (mean change 4.2+/-4.4%, PFMD and reduces LDL susceptibility to oxidation in CAD patients. Improved endothelium-dependent vasodilation and prevention of LDL oxidation are potential mechanisms by which flavonoids in purple grape products may prevent cardiovascular events, independent of alcohol content.

Renal Artery Stenosis (RAS) Case study

International Nuclear Information System (INIS)

Zaater, M.K.

2012-01-01

Renal Artery Stenosis (RAS), is one of the causes of secondary hypertension; there are many causes of renal artery stenosis, as atherosclerosis of the renal artery which account for 90% of cases of RAS; fibromuscular dysplasia accounts for 10% of RAS. Various causes of thrombophilia either due congenital causes or acquired causes and can lead to RAS. Our patient was presented by acute attack of epistaxis and hypertension. Angiography of the Renal Arteries,are showed no sign of renal artery stenosis. However, the right kidney showed upper pole infarction, and the left kidney showed evidence of functional lower pole renal artery stenosis, although there is no anatomical stenosis detected in angiography. Work up for the cause of thrombophilia did not help in the diagnosis, which may be due to an undiscovered cause of thrombophilia

The Effect of Milrinone on the Right Ventriclular Function in Patients with Reduced Right Ventricular Function Undergoing Off-pump Coronary Artery Bypass Graft Surgery

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Lee, Jong Hwa; Oh, Young Jun; Shim, Yon Hee; Hong, Yong Woo; Yi, Gijong

2006-01-01

This investigation evaluated the effect of continuous milrinone infusion on right ventriclular (RV) function during off-pump coronary artery bypass graft (OPCAB) surgery in patients with reduced RV function. Fifty patients scheduled for OPCAB, with thermodilution RV ejection fraction (RVEF) milrinone (0.5 µg/kg/min) or control (saline) group. Hemodynamic variables and RV volumetric data measured by thermodilution method were collected as follows: after anesthesia induction (T1); 10 min after heart displacement for obtuse marginal artery anastomosis (T2); after pericardial closure (T3). Cardiac index and heart rate increased and systemic vascular resistance significantly decreased in milrinone group at T2. Initially lower RVEF of milrinone group was eventually comparable to control group after milrinone infusion. RVEF did not significantly change at T2 and T3 in both groups. RV end-diastolic volume in milrinone group consistently decreased from the baseline at T2 and T3. Continuous infusion of milrinone without a bolus demonstrated potentially beneficial effect on cardiac output and RV afterload in patients with reduced RV function during OPCAB. However, aggressive augmentation of intravascular volume seems to be necessary to maximize the effect of the milrinone in these patients. PMID:17043419

Arterial wave reflection and subclinical left ventricular systolic dysfunction.

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Russo, Cesare; Jin, Zhezhen; Takei, Yasuyoshi; Hasegawa, Takuya; Koshaka, Shun; Palmieri, Vittorio; Elkind, Mitchell Sv; Homma, Shunichi; Sacco, Ralph L; Di Tullio, Marco R

2011-03-01

Increased arterial wave reflection is a predictor of cardiovascular events and has been hypothesized to be a cofactor in the pathophysiology of heart failure. Whether increased wave reflection is inversely associated with left-ventricular (LV) systolic function in individuals without heart failure is not clear. Arterial wave reflection and LV systolic function were assessed in 301 participants from the Cardiovascular Abnormalities and Brain Lesions (CABL) study using two-dimensional echocardiography and applanation tonometry of the radial artery to derive central arterial waveform by a validated transfer function. Aortic augmentation index (AIx) and wasted energy index (WEi) were used as indices of wave reflection. LV systolic function was measured by LV ejection fraction (LVEF) and tissue Doppler imaging (TDI). Mitral annulus peak systolic velocity (Sm), peak longitudinal strain and strain rate were measured. Participants with history of coronary artery disease, atrial fibrillation, LVEF less than 50% or wall motion abnormalities were excluded. Mean age of the study population was 68.3 ± 10.2 years (64.1% women, 65% hypertensive). LV systolic function by TDI was lower with increasing wave reflection, whereas LVEF was not. In multivariate analysis, TDI parameters of LV longitudinal systolic function were significantly and inversely correlated to AIx and WEi (P values from 0.05 to 0.002). In a community cohort without heart failure and with normal LVEF, an increased arterial wave reflection was associated with subclinical reduction in LV systolic function assessed by novel TDI techniques. Further studies are needed to investigate the prognostic implications of this relationship.

Netrin-1 controls sympathetic arterial innervation.

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Brunet, Isabelle; Gordon, Emma; Han, Jinah; Cristofaro, Brunella; Broqueres-You, Dong; Liu, Chun; Bouvrée, Karine; Zhang, Jiasheng; del Toro, Raquel; Mathivet, Thomas; Larrivée, Bruno; Jagu, Julia; Pibouin-Fragner, Laurence; Pardanaud, Luc; Machado, Maria J C; Kennedy, Timothy E; Zhuang, Zhen; Simons, Michael; Levy, Bernard I; Tessier-Lavigne, Marc; Grenz, Almut; Eltzschig, Holger; Eichmann, Anne

2014-07-01

Autonomic sympathetic nerves innervate peripheral resistance arteries, thereby regulating vascular tone and controlling blood supply to organs. Despite the fundamental importance of blood flow control, how sympathetic arterial innervation develops remains largely unknown. Here, we identified the axon guidance cue netrin-1 as an essential factor required for development of arterial innervation in mice. Netrin-1 was produced by arterial smooth muscle cells (SMCs) at the onset of innervation, and arterial innervation required the interaction of netrin-1 with its receptor, deleted in colorectal cancer (DCC), on sympathetic growth cones. Function-blocking approaches, including cell type-specific deletion of the genes encoding Ntn1 in SMCs and Dcc in sympathetic neurons, led to severe and selective reduction of sympathetic innervation and to defective vasoconstriction in resistance arteries. These findings indicate that netrin-1 and DCC are critical for the control of arterial innervation and blood flow regulation in peripheral organs.

Implication of molecular vascular smooth muscle cell heterogeneity among arterial beds in arterial calcification.

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Olivier Espitia

Full Text Available Vascular calcification is a strong and independent predictive factor for cardiovascular complications and mortality. Our previous work identified important discrepancies in plaque composition and calcification types between carotid and femoral arteries. The objective of this study is to further characterize and understand the heterogeneity in vascular calcification among vascular beds, and to identify molecular mechanisms underlying this process. We established ECLAGEN biocollection that encompasses human atherosclerotic lesions and healthy arteries from different locations (abdominal, thoracic aorta, carotid, femoral, and infrapopliteal arteries for histological, cell isolation, and transcriptomic analysis. Our results show that lesion composition differs between these locations. Femoral arteries are the most calcified arteries overall. They develop denser calcifications (sheet-like, nodule, and are highly susceptible to osteoid metaplasia. These discrepancies may derive from intrinsic differences between SMCs originating from these locations, as microarray analysis showed specific transcriptomic profiles between primary SMCs isolated from each arterial bed. These molecular differences translated into functional disparities. SMC from femoral arteries showed the highest propensity to mineralize due to an increase in basal TGFβ signaling. Our results suggest that biological heterogeneity of resident vascular cells between arterial beds, reflected by our transcriptomic analysis, is critical in understanding plaque biology and calcification, and may have strong implications in vascular therapeutic approaches.

Magnetic resonance imaging of athlete's heart: myocardial mass, left ventricular function, and cross-sectional area of the coronary arteries

International Nuclear Information System (INIS)

Zandrino, F.; Sardanelli, F.; Molinari, G.; Masperone, M.A.; Smeraldi, A.; Odaglia, G.

2000-01-01

To evaluate left ventricular myocardial mass and function as well as ostial coronary artery cross-sectional area in endurance athletes, an athlete group of 12 highly trained rowers and a control group of 12 sedentary healthy subjects underwent MR examination. An ECG-gated breath-hold cine gradient-echo sequence was used to calculate myocardial mass, end-diastolic and end-systolic volumes, stroke volume, and cardiac output, all related to body surface area, as well as ejection fraction. A 3D fat-saturated ECG- and respiratory-triggered navigator echo sequence was used to evaluate coronary arteries: left main (LM), left anterior descending (LAD), left circumflex (LCx), and right coronary artery (RCA). Cross-sectional area was calculated and divided for body surface area. Myocardial mass was found significantly larger in athlete group than in control group (p = 0.0078), the same being for end-diastolic volume (p = 0.0078), stroke volume (p = 0.0055), LM (p = 0.0066) and LAD (p = 0.0129). No significant difference was found for all the remaining parameters. Significant correlation with myocardial mass was found for LM (p < 0.001) and LAD (p = 0.0340), not for LCx and RCA. Magnetic resonance imaging is a useful tool in evaluating the myocardial hypertrophy and function of athlete's heart. Magnetic resonance angiography is a valuable noninvasive method to visualize the correlated cross-sectional area increase of the left coronary artery system. (orig.)

Functional ET(A)-ET(B) Receptor Cross-talk in Basilar Artery In Situ From ET(B) Receptor Deficient Rats.

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Yoon, SeongHun; Gariepy, Cheryl E; Yanagisawa, Masashi; Zuccarello, Mario; Rapoport, Robert M

2016-03-01

The role of endothelin (ET)(A)-ET(B) receptor cross-talk in limiting the ET(A) receptor antagonist inhibition of ET-1 constriction is revealed by the partial or complete dependency of the ET(A) receptor antagonist inhibition on functional removal of the ET(B) receptor. Although functional removal of the ET(B) receptor is generally accomplished with ET(B) receptor antagonist, a novel approach using rats containing a naturally occurring deletion mutation in the ET(B) receptor [rescued "spotting lethal" (sl) rats; ET(B)(sl/sl)] demonstrated increased ET(A) receptor antagonist inhibition of ET-1 constriction in vena cava. We investigated whether this deletion mutation was also sufficient to remove the ET(B) receptor dependency of the ET(A) receptor antagonist inhibition of ET-1 constriction in the basilar artery. Consistent with previous reports, ET-1 plasma levels were elevated in ET(B)(sl/sl) as compared with ET(B)(+/+) rats. ET(B) receptor antagonist failed to relax the ET-1 constricted basilar artery from ET(B)(+/+) and ET(B)(sl/sl) rats. Relaxation to combined ET(A) and ET(B) receptor antagonist was greater than relaxation to ET(A) receptor antagonist in the basilar artery from ET(B)(+/+) and, unexpectedly, ET(B)(sl/sl) rats. These findings confirm the presence of ET(A)-ET(B) receptor cross-talk in the basilar artery. We speculate that mutant ET(B) receptor expression produced by alternative splicing may be sufficient to allow cross-talk.

Radioindication of hemodynamics and functional state of parenchyma of the kidneys in stenosis of renal arteries

International Nuclear Information System (INIS)

Efimov, O.N.; Gabuniya, R.I.; Kamynin, Yu.F.; Matveenko, E.G.; Buyuklyan, A.N.; Skoropad, L.S.; Syzgantseva, L.M.

1978-01-01

Hemodynamics and functional state of parenchyma of the kidney were studied in 39 patients with stenosis of the renal arteries by means of pertechnetate 99 Tc, hippuran 131 I and chlormerodrine 197 Hg. In patients with vasorenal hypertension the following changes in the stenosed kidney were revealed: a significant decrease in the renal blood flow, renal fraction, volume of maximal saturation, specific blood flow, systolic renal index; elevation of the intrarenal vascular resistance; and impairment of the functional state of the renal parenchyma. It was established that there was a direct dependence between the renal blood flow and the volume of maximal saturation and a reverse dependence between the renal blood flow and intrarenal vascular resistance. Hemodynamic changes in the stenosed kidney played an important role and led at first to a bias in renographic indices and then - to a decrease in accumulation of chlormerodrine 197 Hg in the kidneys. It was noted that changes in the functional state of the renal parenchyma tended to be dependent upon the level of the renal blood flow, and indices of the renal blood flow - upon the values of arterial pressure. From diagnostic point of view, methods of radioiangiography, as compared with renography and scintigraphy, were found to be the most informative

The influence of anatomic variance in the coronary artery on cardiac function with PCI after acute inferior wall myocardial infarction

International Nuclear Information System (INIS)

Zheng Hongming; Feng Jue; Fang Fengning; Wu Heping; Wang Fengqin; Ma Huili

2006-01-01

Objective: To analyze the influence in anatomic variance of coronary artery on function of left and right ventricles after acute inferior myocardial infarction (AIMI) treated with percutaneous coronary intervention therapy (PCI). Methods: Forty-seven inferior AIMI patients were divided into 2 groups: 12 left dominant group [including equipollent case, i.e. inferior wall of left ventricle supplied by left circumflex coronary artery (LCX), right ventricle by right coronary artery (RCA)] and 35 right dominant group (both inferior wall and right ventricle were supplied by RCA). Equilibrium radionuclide angiocardiography (ERNA) and myocardial perfusion imaging (MPI) were used for comparing the influence between different coronary artery flow patterns on biventricular hemodynamics, blood supply and prognosis of PCI after 3 months. Results: Comparison of ventricular function in left and right dominant coronal artery type groups discharged 7- 10 d after PCI, there were differences in left ventricular ejection fraction (LVEF) [(63.03 ± 5.64)% vs (57.67 ± 7.35)%, P=0.012], peak ejection rate (PER) [(3.52 ± 0.66) end-diastolic volume (EDV)/s vs (2.93 ± 0.73) EDV/s, P =0.011], peak filling rate (PFR) [(2.71 ± 0.88) EDV/s vs (2.11 ± 0.45 ) EDV/s, P=0.004], left free-wall regional ejection fraction [(81.94 ± 20.75)% vs (67.25 ± 16.54)%, P = O.032], and right free-wall regional ejection fraction [(57.86 ± 11.77)% vs (67.83 ± 10.38)%, P=0.012], right ventricular ejection fraction (RVEF) [(37.89 ± 3.86)% vs (41.67 ± 4.81)%, P=0.09]. After 3 months,there was difference only in RVEF [(44.60 ± 5.29)% vs (48.00 ± 3.30)%, P=0.043], but no difference in myocardial perfusion of left ventricle (P=0.357). Conclusions: In acute stage of AIMI right dominant group, there was more severe injury of right ventricle, in convalescent stage most of the right ventricular function resumed. The sustained right ventricular function in part of the patients can be demonstrated by ERNA

Pulmonary artery radiocardiography and rheography in the diagnosis of hemodynamic and contractile function impairments of the right ventricle in patients with obstructive bronchitis

International Nuclear Information System (INIS)

Paleev, N.P.; Cherejskaya, N.K.; Tsar'kova, L.N.; Baklykova, S.N.; Novoderezhkina, L.B.; Oblovatskaya, O.G.; Dubinina, E.B.

1990-01-01

Radiocardiography and rheography of the pulmonary artery were used to examine impairments in hemodynamics and contractile function of the right ventricle in 40 patients with chronic obstructive bronchitis complicated with persistent hypertension. Right ventricular hemodynamic and contractile impairments were shown to be not equivalent with similar clinical and functional signs of pulmonary hypertension. This fact indicates that the use of special techiques is of practical value in the determination of right ventricular hemodynamics and myocardial contractility in patients with chronic obstructive bronchitis. Radiocardiography and rheography of the pulmonary artery are sufficiently reliable noninvasive techniques for examining the hemodynamics and contractile function of the right ventricular myocardium

Baroreflex Sensitivity and its Association with Arrhythmic Events in Chagas Disease

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Astrid Meireles Santos

2014-07-01

Full Text Available Background: Sudden death is the leading cause of death in Chagas disease (CD, even in patients with preserved ejection fraction (EF, suggesting that destabilizing factors of the arrhythmogenic substrate (autonomic modulation contribute to its occurrence. Objective: To determine baroreflex sensitivity (BRS in patients with undetermined CD (GI, arrhythmogenic CD with nonsustained ventricular tachycardia (NSVT (GII and CD with spontaneous sustained ventricular tachycardia (STV (GIII, to evaluate its association with the occurrence and complexity of arrhythmias. Method: Forty-two patients with CD underwent ECG and continuous and noninvasive BP monitoring (TASK force monitor. The following were determined: BRS (phenylephrine method; heart rate variability (HRV on 24-h Holter; and EF (echocardiogram. Results: GIII had lower BRS (6.09 ms/mm Hg as compared to GII (11.84 and GI (15.23. The difference was significant between GI and GIII (p = 0.01. Correlating BRS with the density of ventricular extrasystoles (VE, low VE density ( 10/h had preserved BRS (p = 0.003. Patients with depressed BRS had higher VE density (p = 0.01, regardless of the EF. The BRS was the only variable related to the occurrence of SVT (p = 0.028. Conclusion: The BRS is preserved in undetermined CD. The BRS impairment increases as disease progresses, being more severe in patients with more complex ventricular arrhythmias. The degree of autonomic dysfunction did not correlate with EF, but with the density and complexity of ventricular arrhythmias.

Baroreflexes of the rat. IV. ADN-evoked responses at the NTS.

Science.gov (United States)

Tang, Xiaorui; Dworkin, Barry R

2007-12-01

In a long-term (7-21 days) neuromuscular blocked (NMB) rat preparation, using precise single-pulse aortic depressor nerve (ADN) stimulation and stable chronic evoked response (ER) recordings from the dorsal-medial solitary nucleus (dmNTS), two different response patterns were observed: continuous and discrete. For the continuous pattern, activity began approximately 3 ms after the stimulus and persisted for 45 ms; for the discrete pattern, two complexes were separated by a gap from approximately 17 to 25 ms. The early complex was probably transmitted via A-fibers: it had a low stimulus current threshold and an average conduction velocity (CV) of 0.58-5.5 m/s; the high threshold late (HTL) complex had a CV = 0.26-0.58 m/s. The average stimulus amplitude-ER magnitude transduction curves for the A and HTL complexes were sigmoidal. For individual rats, in the linear range, mean r2 = 0.96 +/- 0.03 for both complexes. The average stimulus amplitude vs. the systolic blood pressure change (delta sBP) transduction curve was also approximately linear; however, for individual rats, the relationship was not consistently reliable: mean r2 = 0.48 +/- 0.19. Approximately 90% of recording sites had respiratory, and 50% had cardiac synchronism. The NMB preparation is useful for studying central baroreflex mechanisms that operate on time scales of days or weeks, such as adaptation and other kinds of neural plasticity.

Joint symbolic dynamics for the assessment of cardiovascular and cardiorespiratory interactions.

Science.gov (United States)

Baumert, Mathias; Javorka, Michal; Kabir, Muammar

2015-02-13

Beat-to-beat variations in heart period provide information on cardiovascular control and are closely linked to variations in arterial pressure and respiration. Joint symbolic analysis of heart period, systolic arterial pressure and respiration allows for a simple description of their shared short-term dynamics that are governed by cardiac baroreflex control and cardiorespiratory coupling. In this review, we discuss methodology and research applications. Studies suggest that analysis of joint symbolic dynamics provides a powerful tool for identifying physiological and pathophysiological changes in cardiovascular and cardiorespiratory control.

“Transcollateral” Renal Angioplasty for a Completely Occluded Renal Artery

International Nuclear Information System (INIS)

Chandra, Subash; Chadha, Davinder S.; Swamy, Ajay

2011-01-01

Percutaneous transluminal renal angioplasty with stenting has been effective in the control of hypertension, renal function, and pulmonary edema caused by atherosclerotic renal artery stenosis. However, the role of the procedure has not been fully established in the context of chronic total occlusion of renal artery. We report the successful use of this procedure in 57-year-old male patient who reported for evaluation of a recent episode of accelerated hypertension. A renal angiogram in this patient showed ostial stenosis of the right renal artery, which was filling by way of the collateral artery. Renal angioplasty for chronic total occlusion of right renal artery was successfully performed in a retrograde fashion through a collateral artery, thereby leading to improvement of renal function and blood pressure control.

Pulmonary artery wave propagation and reservoir function in conscious man: impact of pulmonary vascular disease, respiration and dynamic stress tests

DEFF Research Database (Denmark)

Su, Junjing; Manisty, Charlotte; Simonsen, Ulf

2017-01-01

Detailed haemodynamic analysis may provide novel insights into the pulmonary circulation. Therefore, wave intensity and reservoir-excess pressure analyses were applied in the pulmonary artery to characterize changes in wave propagation and reservoir function during spontaneous respiration......, recordings were also obtained during Valsalva manoeuvre and handgrip exercise. The asymptotic pressure at which the flow through the microcirculation ceases, the reservoir pressure related to arterial compliance and the excess pressure caused by arterial waves increased in PAH patients compared to controls....... The systolic and diastolic rate constants also increased, while the diastolic time constant decreased. The forward compression wave energy decreased by ∼8% in controls and ∼6% in PAH patients during expiration compared to inspiration, while the wave speed remained unchanged throughout the respiratory cycle...

Estimation of Pulse Transit Time as a Function of Blood Pressure Using a Nonlinear Arterial Tube-Load Model.

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Gao, Mingwu; Cheng, Hao-Min; Sung, Shih-Hsien; Chen, Chen-Huan; Olivier, Nicholas Bari; Mukkamala, Ramakrishna

2017-07-01

pulse transit time (PTT) varies with blood pressure (BP) throughout the cardiac cycle, yet, because of wave reflection, only one PTT value at the diastolic BP level is conventionally estimated from proximal and distal BP waveforms. The objective was to establish a technique to estimate multiple PTT values at different BP levels in the cardiac cycle. a technique was developed for estimating PTT as a function of BP (to indicate the PTT value for every BP level) from proximal and distal BP waveforms. First, a mathematical transformation from one waveform to the other is defined in terms of the parameters of a nonlinear arterial tube-load model accounting for BP-dependent arterial compliance and wave reflection. Then, the parameters are estimated by optimally fitting the waveforms to each other via the model-based transformation. Finally, PTT as a function of BP is specified by the parameters. The technique was assessed in animals and patients in several ways including the ability of its estimated PTT-BP function to serve as a subject-specific curve for calibrating PTT to BP. the calibration curve derived by the technique during a baseline period yielded bias and precision errors in mean BP of 5.1 ± 0.9 and 6.6 ± 1.0 mmHg, respectively, during hemodynamic interventions that varied mean BP widely. the new technique may permit, for the first time, estimation of PTT values throughout the cardiac cycle from proximal and distal waveforms. the technique could potentially be applied to improve arterial stiffness monitoring and help realize cuff-less BP monitoring.

Nonischemic changes in right ventricular function on exercise. Do normal volunteers differ from patients with normal coronary arteries

International Nuclear Information System (INIS)

Caplin, J.L.; Maltz, M.B.; Flatman, W.D.; Dymond, D.S.

1988-01-01

Factors other than ischemia may alter right ventricular function both at rest and on exercise. Normal volunteers differ from cardiac patients with normal coronary arteries with regard to their left ventricular response to exercise. This study examined changes in right ventricular function on exercise in 21 normal volunteers and 13 patients with normal coronary arteries, using first-pass radionuclide angiography. There were large ranges of right ventricular ejection fraction in the two groups, both at rest and on exercise. Resting right ventricular ejection fraction was 40.2 +/- 10.6% (mean +/- SD) in the volunteers and 38.6 +/- 9.7% in the patients, p = not significant, and on exercise rose significantly in both groups to 46.1 +/- 9.9% and 45.8 +/- 9.7%, respectively. The difference between the groups was not significant. In both groups some subjects with high resting values showed large decreases in ejection fraction on exercise, and there were significant negative correlations between resting ejection fraction and the change on exercise, r = -0.59 (p less than 0.01) in volunteers, and r = -0.66 (p less than 0.05) in patients. Older volunteers tended to have lower rest and exercise ejection fractions, but there was no difference between normotensive and hypertensive patients in their rest or exercise values. In conclusion, changes in right ventricular function on exercise are similar in normal volunteers and in patients with normal coronary arteries. Some subjects show decreases in right ventricular ejection fraction on exercise which do not appear to be related to ischemia

Physiological basis for human autonomic rhythms

Science.gov (United States)

Eckberg, D. L.

2000-01-01

Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a

The genetic basis for altered blood vessel function in disease: large artery stiffening

Directory of Open Access Journals (Sweden)

Alex Agrotis

2005-12-01

Full Text Available Alex AgrotisThe Cell Biology Laboratory, Baker Heart Research Institute, Melbourne, Victoria, AustraliaAbstract: The progressive stiffening of the large arteries in humans that occurs during aging constitutes a potential risk factor for increased cardiovascular morbidity and mortality, and is accompanied by an elevation in systolic blood pressure and pulse pressure. While the underlying basis for these changes remains to be fully elucidated, factors that are able to influence the structure and composition of the extracellular matrix and the way it interacts with arterial smooth muscle cells could profoundly affect the properties of the large arteries. Thus, while age and sex represent important factors contributing to large artery stiffening, the variation in growth-stimulating factors and those that modulate extracellular production and homeostasis are also being increasingly recognized to play a key role in the process. Therefore, elucidating the contribution that genetic variation makes to large artery stiffening could ultimately provide the basis for clinical strategies designed to regulate the process for therapeutic benefit.Keywords: arterial stiffness, genes, polymorphism, extracellular matrix proteins

The quantitative regional cerebral blood flow measurement with autoradiography method using 123I-IMP SPECT. Evaluation of arterialized venous blood sampling as a substitute for arterial blood sampling

International Nuclear Information System (INIS)

Ohnishi, Takashi; Yano, Takao; Nakano, Shinichi; Jinnouchi, Seishi; Nagamachi, Shigeki; Flores, L. II; Nakahara, Hiroshi; Watanabe, Katsushi.

1996-01-01

The purpose of this study is validation of calibrating a standard input function in autoradiography (ARG) method by one point venous blood sampling as a substitute for that by one point arterial blood sampling. Ten and 20 minutes after intravenous constant infusion of 123 I-IMP, arterialized venous blood sampling from a dorsal vein were performed on 15 patients having ischemic cerebrovascular disease. And arterial blood sampling from radial artery was performed 10 min after 123 I-IMP infusion. The mean difference rates of integrated input function between calibrated standard input function by arterial blood sampling at 10 min and that by venous blood sampling were 4.1±3% and 9.3±5.4% at 10 and 20 min after 123 I-IMP infusion, respectively. The ratio of venous blood radioactivity to arterial blood radioactivity at 10 min after 123 I-IMP infusion was 0.96±0.02. There was an excellent correlation between ARG method CBF values obtained by arterial blood sampling at 10 min and those obtained by arterialized venous blood sampling at 10 min. In conclusion, a substitution by arterialized venous blood sampling from dorsal hand vein for artery can be possible. The optimized time for arterialized venous blood sampling was 10 min after 123 I-IMP infusion. (author)

Pressure Myography to Study the Function and Structure of isolated small arteries

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Schjørring, Olav; Carlsson, Rune; Simonsen, Ulf

2015-01-01

Small arteries play an important role in regulation of peripheral resistance and organ perfusion. Here we describe a series of the methods allowing measurements in pressurized segments of small arteries from the systemic and coronary circulation of mice as well as other species. The pressure...... myography techniques described include measurements of wall structure, wall stress, strain, and of myogenic tone. The pressurized perfused small arteries also allow evaluation of responses to increases in pressure, flow, and drugs, where the main readout is changes in vascular diameter....

Anomalous left coronary artery from the pulmonary artery with a large patent ductus arteriosus: aversion of a catastrophe.

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Aggarwal, Sanjeev; Delius, Ralph E; Pettersen, Michael D

2013-01-01

We present an infant who had an anomalous left coronary artery arising from the pulmonary artery (ALCAPA) and a large patent ductus arteriosus (PDA), who was diagnosed before a potentially catastrophic closure of PDA. In the presence of normal left ventricular function and the absence of coronary artery collaterals, it is difficult to diagnose ALCAPA. A disproportionate degree of left ventricular dilation and severity of mitral valve regurgitation relative to the degree of PDA shunt, and echogenic papillary muscles on an echocardiogram should raise a suspicion of coronary artery anomalies. The infant underwent surgical ligation of PDA with translocation of coronary arteries and had an uneventful recovery. © 2012 Wiley Periodicals, Inc.

Colchicine Depolymerizes Microtubules, Increases Junctophilin-2, and Improves Right Ventricular Function in Experimental Pulmonary Arterial Hypertension.

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Prins, Kurt W; Tian, Lian; Wu, Danchen; Thenappan, Thenappan; Metzger, Joseph M; Archer, Stephen L

2017-05-31

Pulmonary arterial hypertension (PAH) is a lethal disease characterized by obstructive pulmonary vascular remodeling and right ventricular (RV) dysfunction. Although RV function predicts outcomes in PAH, mechanisms of RV dysfunction are poorly understood, and RV-targeted therapies are lacking. We hypothesized that in PAH, abnormal microtubular structure in RV cardiomyocytes impairs RV function by reducing junctophilin-2 (JPH2) expression, resulting in t-tubule derangements. Conversely, we assessed whether colchicine, a microtubule-depolymerizing agent, could increase JPH2 expression and enhance RV function in monocrotaline-induced PAH. Immunoblots, confocal microscopy, echocardiography, cardiac catheterization, and treadmill testing were used to examine colchicine's (0.5 mg/kg 3 times/week) effects on pulmonary hemodynamics, RV function, and functional capacity. Rats were treated with saline (n=28) or colchicine (n=24) for 3 weeks, beginning 1 week after monocrotaline (60 mg/kg, subcutaneous). In the monocrotaline RV, but not the left ventricle, microtubule density is increased, and JPH2 expression is reduced, with loss of t-tubule localization and t-tubule disarray. Colchicine reduces microtubule density, increases JPH2 expression, and improves t-tubule morphology in RV cardiomyocytes. Colchicine therapy diminishes RV hypertrophy, improves RV function, and enhances RV-pulmonary artery coupling. Colchicine reduces small pulmonary arteriolar thickness and improves pulmonary hemodynamics. Finally, colchicine increases exercise capacity. Monocrotaline-induced PAH causes RV-specific derangement of microtubules marked by reduction in JPH2 and t-tubule disarray. Colchicine reduces microtubule density, increases JPH2 expression, and improves both t-tubule architecture and RV function. Colchicine also reduces adverse pulmonary vascular remodeling. These results provide biological plausibility for a clinical trial to repurpose colchicine as a RV-directed therapy for PAH

The impact of the ketogenic diet on arterial morphology and endothelial function in children and young adults with epilepsy: a case-control study.

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Coppola, Giangennaro; Natale, Francesco; Torino, Annarita; Capasso, Rosanna; D'Aniello, Alfredo; Pironti, Erica; Santoro, Elena; Calabrò, Raffaele; Verrotti, Alberto

2014-04-01

The present study aimed to assess the impact of the ketogenic diet on arterial morphology and endothelial function of the big vessels of the neck and on cardiac diastolic function, in a cohort of epileptic children and young adults treated with the ketogenic diet. Patients were recruited based on the following inclusion criteria: (1) patients who were or had been on the ketogenic diet for a time period of at least six months. Each patient underwent measurement of carotid intima media thickness, carotid artery stiffness, echocardiography, and diastolic function assessment. Patients with drug resistant epilepsy, matched for number, age and sex and never treated with ketogenic diet, were recruited as controls. The population study was composed by 43 epilepsy patients (23 males), aged between 19 months and 31 years (mean 11 years). Twenty-three patients were or had been treated with ketogenic diet, and 20 had never been on it (control group). Subjects treated with the ketogenic diet had higher arterial stiffness parameters, including AIx and β-index and higher serum levels of cholesterol or triglycerides compared to those who had never been on the diet (control group) (pketogenic diet, before the increase of the intima media thickness. This supports that arterial stiffness is an early marker of vascular damage. Copyright © 2013 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

Focused ultrasound-modulated glomerular ultrafiltration assessed by functional changes in renal arteries.

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Feng-Yi Yang

Full Text Available This study demonstrates the feasibility of using focused ultrasound (FUS to modulate glomerular ultrafiltration by renal artery sonication and determine if protein-creatinine ratios are estimated through vascular parameters. All animal experiments were approved by our Animal Care and Use Committee. The renal arteries of Sprague-Dawley rats were surgically exposed and sonicated at various acoustic power levels using a FUS transducer with a resonant frequency of 1 MHz. The mean peak systolic velocity (PSV of the blood flow was measured by Doppler ultrasound imaging. Urinary protein-creatinine ratios were calculated during the experiments. Histological examination of renal arteries and whole kidneys was performed. The PSV, pulsatility index, and resistance index of blood flow significantly increased in the arteries after FUS sonication without microbubbles (p<0.05. The change in normalized protein-creatinine ratios significantly increased with increasing acoustic power, but such was not observed when microbubbles were administered. Furthermore, no histological changes were observed in the hematoxylin- and eosin-stained sections. Glomerular ultrafiltration is regulated temporarily by renal artery sonication without microbubbles. Monitoring vascular parameters are useful in estimating the normalized change in protein-creatinine ratios.

Reduced baroreflex sensitivity and pulmonary dysfunction in alcoholic cirrhosis: effect of hyperoxia

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Møller, Søren; Iversen, Jens S; Krag, Aleksander

2010-01-01

matched controls underwent hemodynamic and pulmonary investigations. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. A 100% oxygen test was performed with the assessment of arterial oxygen tensions (Pa(O(2))) and alveolar-arterial oxygen...

Pleurotomy with subxyphoid pleural drain affords similar effects to pleural integrity in pulmonary function after off-pump coronary artery bypass graft.

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Guizilini, Solange; Bolzan, Douglas W; Faresin, Sonia M; Ferraz, Raquel F; Tavolaro, Kelly; Cancio, Andrea A; Gomes, Walter J

2012-01-25

Exacerbation of pulmonary dysfunction has been reported in patients receiving a pleural drain inserted through the intercostal space in comparison to patients with an intact pleura undergoing coronary artery bypass grafting (CABG). Evidence suggests that shifting the site of pleural drain insertion to the subxyphoid position minimizes chest wall trauma and preserves respiratory function in the early postoperative period. The aim of this study was to compare the pulmonary function parameters, clinical outcomes, and pain score between patients undergoing pleurotomy with pleural drain placed in the subxyphoid position and patients with intact pleural cavity after off-pump CABG (OPCAB) using left internal thoracic artery (LITA). Seventy-one patients were allocated into two groups: I (n = 38 open left pleural cavity and pleural drain inserted in the subxyphoid position); II (n = 33 intact pleural cavity). Pulmonary function tests and clinical parameters were recorded preoperatively and on postoperative days (POD) 1, 3 and 5. Arterial blood gas analysis and shunt fraction were evaluated preoperatively and in POD1. Pain score was assessed on POD1. To monitor pleural effusion and atelectasis chest radiography was performed routinely 1 day before operation and until POD5. In both groups a significant impairment was found in lung function parameters until on POD5. However, no significant difference in forced vital capacity and forced expiratory volume in 1 second were seen between groups. A significant decrease in partial pressure of arterial oxygen and an increase in shunt fraction values were observed on POD1 in both groups, but no statistical difference was found when the groups were compared. Pleural effusion and atelectasis until on POD5 were similar in both groups. There were no statistical differences in pain score, duration of mechanical ventilation and postoperative hospital stay between groups. Subxyphoid insertion of pleural drain provides similar effects to

Heart transplantation and arterial elasticity

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Colvin-Adams M

2013-12-01

Full Text Available Monica Colvin-Adams,1 Nonyelum Harcourt,1 Robert LeDuc,2 Ganesh Raveendran,1 Yassir Sonbol,3 Robert Wilson,1 Daniel Duprez11Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA; 2Division of Biostatistics University of Minnesota, Minneapolis, MN, USA; 3Cardiovascular Division, St Luke's Hospital System, Sugar Land, TX, USAObjective: Arterial elasticity is a functional biomarker that has predictive value for cardiovascular morbidity and mortality in nontransplant populations. There is little information regarding arterial elasticity in heart transplant recipients. This study aimed to characterize small (SAE and large (LAE artery elasticity in heart transplant recipients in comparison with an asymptomatic population free of overt cardiovascular disease. A second goal was to identify demographic and clinical factors associated with arterial elasticity in this unique population.Methods: Arterial pulse waveform was registered noninvasively at the radial artery in 71 heart transplant recipients between 2008 and 2010. SAEs and LAEs were derived from diastolic pulse contour analysis. Comparisons were made to a healthy cohort of 1,808 participants selected from our prevention clinic database. Multiple regression analyses were performed to evaluate associations between risk factors and SAE and LAE within the heart transplant recipients.Results: LAE and SAE were significantly lower in heart transplant recipients than in the normal cohort (P <0.01 and P < 0.0001, respectively. Female sex and history of ischemic cardiomyopathy were significantly associated with reduced LAE and SAE. Older age and the presence of moderate cardiac allograft vasculopathy were also significantly associated with reduced SAE. Transplant duration was associated with increased SAE.Conclusion: Heart transplants are associated with peripheral endothelial dysfunction and arterial stiffness, as demonstrated by a significant reduction in SAE and LAE when compared with a

Hepatic artery aneurysm repair: a case report

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Jaunoo SS

2009-01-01

Full Text Available Abstract Introduction Hepatic artery aneurysms remain a clinically significant entity. Their incidence continues to rise slowly and mortality from spontaneous rupture is high. Repair is recommended in those aneurysms greater than 2 cm in diameter. It is not surprising that vascular comorbidities, such as ischaemic heart disease, are common in surgical patients, particularly those with arterial aneurysms such as these. The decision of when to operate on patients who require urgent surgery despite having recently suffered an acute coronary syndrome remains somewhat of a grey and controversial area. We discuss the role of delayed surgery and postoperative followup of this vascular problem. Case presentation A 58-year-old man was admitted with a 5.5 cm hepatic artery aneurysm. The aneurysm was asymptomatic and was an incidental finding as a result of an abdominal computed tomography scan to investigate an episode of haemoptysis (Figure 1. Three weeks prior to admission, the patient had suffered a large inferior myocardial infarction and was treated by thrombolysis and primary coronary angioplasty. Angiographic assessment revealed a large aneurysm of the common hepatic artery involving the origins of the hepatic, gastroduodenal, left and right gastric arteries and the splenic artery (Figures 2 and 3. Endovascular treatment was not considered feasible and immediate surgery was too high-risk in the early post-infarction period. Therefore, surgery was delayed for 3 months when aneurysm repair with reconstruction of the hepatic artery was successfully performed. Graft patency was confirmed with the aid of an abdominal arterial duplex. Plasma levels of conventional liver function enzymes and of alpha-glutathione-S-transferase were within normal limits. This was used to assess the extent of any hepatocellular damage perioperatively. The patient made a good recovery and was well at his routine outpatient check-ups. Conclusion There is no significant

The influence of contrast media on kidney function in patients with stable coronary artery disease

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Reuter, Simon Bertram; Harutyunyan, Marina; Mygind, Naja Dam

2014-01-01

AIMS: To investigate the incidence of contrast media-induced nephropathy (CIN) in patients with stable coronary artery disease (CAD) referred for elective coronary intervention following hydration routines. The reversibility of CIN was followed in a 6 month-period. METHODS AND RESULTS: A total...... coronary interventions. Kidney function and the amount of contrast media used was not a predictor of CIN development. The induced CIN was not completely normalized in a 6-month follow-up period....

[Vascular aging, arterial hypertension and physical activity].

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Schmidt-Trucksäss, A; Weisser, B

2011-11-01

The present review delineates the significance of intima-media-thickness, arterial stiffness and endothelial function for vascular aging. There is profound evidence for an increase in intima-media-thickness and vascular stiffness not only during healthy aging but induced also by cardiovascular risk factors. There is a central role of arterial hypertension for this progression in both structural factors. In addition, both parameters are strongly associated with cardiovascular risk. Endothelial function measured as postischemic flow-mediated vasodilatation is a functional parameter which is decreased both in healthy aging and by cardiovascular risk factors. Physical activity modifies the influence of aging and risk factors on endothelial function. A positive influence of endurance exercise on vascular stiffness and endothelial function has been demonstrated in numerous studies. In long-term studies, regular physical activity has been shown to reduce the progression of intima-media-thickness. Thus, arterial hypertension accelerates vascular aging, while physical activity has a positive influence on a variety of vascular parameters associated with vascular aging. © Georg Thieme Verlag KG Stuttgart · New York.

Unraveling the relationship between arterial flow and intra-aneurysmal hemodynamics.

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Morales, Hernán G; Bonnefous, Odile

2015-02-26

Arterial flow rate affects intra-aneurysmal hemodynamics but it is not clear how their relationship is. This uncertainty hinders the comparison among studies, including clinical evaluations, like a pre- and post-treatment status, since arterial flow rates may differ at each time acquisition. The purposes of this work are as follows: (1) To study how intra-aneurysmal hemodynamics changes within the full physiological range of arterial flow rates. (2) To provide characteristic curves of intra-aneurysmal velocity, wall shear stress (WSS) and pressure as functions of the arterial flow rate. Fifteen image-based aneurysm models were studied using computational fluid dynamics (CFD) simulations. The full range of physiological arterial flow rates reported in the literature was covered by 11 pulsatile simulations. For each aneurysm, the spatiotemporal-averaged blood flow velocity, WSS and pressure were calculated. Spatiotemporal-averaged velocity inside the aneurysm linearly increases as a function of the mean arterial flow (minimum R(2)>0.963). Spatiotemporal-averaged WSS and pressure at the aneurysm wall can be represented by quadratic functions of the arterial flow rate (minimum R(2)>0.996). Quantitative characterizations of spatiotemporal-averaged velocity, WSS and pressure inside cerebral aneurysms can be obtained with respect to the arterial flow rate. These characteristic curves provide more information of the relationship between arterial flow and aneurysm hemodynamics since the full range of arterial flow rates is considered. Having these curves, it is possible to compare experimental studies and clinical evaluations when different flow conditions are used. Copyright © 2015 Elsevier Ltd. All rights reserved.

Uterine arterial embolization to treat uterine leiomyoma

International Nuclear Information System (INIS)

Wang Huali; Han Lu; Wang Feng

2002-01-01

Objective: To assess the clinical effects of uterine arterial embolization on uterine leiomyoma. Methods: The authors treated 21 patients with uterine leiomyoma by Seldinger's uterine arterial embolization. The 4.0 F Cobra catheter was laced into the double uterine arteries with Polyvinyl Alcohol Foam (PVA) particles as the embolization. At 3 and 6 months postoperatively, the authors investigated the effects of the embolization. Results: After uterine arterial embolization, the volume of uterine leiomyoma decreased and menorrhagia was under controlled. The symptoms of anemia and oppression were relieved. The physiologic functions of ovary and uterus were preserved completely. Conclusions: Uterine arterial embolization is an effective and less invasive way to treat uterine leiomyoma

Clinical review: Cardiovascular consequences of ovarian disruption: a focus on functional hypothalamic amenorrhea in physically active women.

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O'Donnell, Emma; Goodman, Jack M; Harvey, Paula J

2011-12-01

Evidence indicates that hypoestrogenemia is linked with accelerated progression of atherosclerosis. Premenopausal women presenting with ovulatory disruption due to functional hypothalamic amenorrhea (FHA) are characterized by hypoestrogenemia. One common and reversible form of FHA in association with energy deficiency is exercise-associated amenorrhea (EAA). Articles were found via PubMed search for both original and review articles based on peer review publications between 1974 and 2011 reporting on cardiovascular changes in women with FHA, with emphasis placed on women with EAA. Despite participation in regular exercise training, hypoestrogenic women with EAA demonstrate paradoxical changes in cardiovascular function, including endothelial dysfunction, a known permissive factor for the progression and development of atherosclerosis. Such alterations suggest that the beneficial effects of regular exercise training on vascular function are obviated in the face of hypoestrogenemia. The long-term cardiovascular consequences of altered vascular function in response to ovulatory disruption in women with EAA remain to be determined. Retrospective data, however, suggest premature development and progression of coronary artery disease in older premenopausal women reporting a history of hypothalamic ovulatory disruption. Importantly, in women with EAA, estrogen therapy, folic acid supplementation without change in menstrual status, and resumption of menses restores endothelial function. In this review, we focus on the influence of hypoestrogenemia in association with energy deficiency in mediating changes in cardiovascular function in women with EAA, including endothelial function, regional blood flow, lipid profile, and autonomic control of blood pressure, heart rate, and baroreflex sensitivity. The influence of exercise training is also considered. With the premenopausal years typically considered to be cardioprotective in association with normal ovarian function

Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adults.

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West, Sheila G; McIntyre, Molly D; Piotrowski, Matthew J; Poupin, Nathalie; Miller, Debra L; Preston, Amy G; Wagner, Paul; Groves, Lisa F; Skulas-Ray, Ann C

2014-02-01

The consumption of cocoa and dark chocolate is associated with a lower risk of CVD, and improvements in endothelial function may mediate this relationship. Less is known about the effects of cocoa/chocolate on the augmentation index (AI), a measure of vascular stiffness and vascular tone in the peripheral arterioles. We enrolled thirty middle-aged, overweight adults in a randomised, placebo-controlled, 4-week, cross-over study. During the active treatment (cocoa) period, the participants consumed 37 g/d of dark chocolate and a sugar-free cocoa beverage (total cocoa = 22 g/d, total flavanols (TF) = 814 mg/d). Colour-matched controls included a low-flavanol chocolate bar and a cocoa-free beverage with no added sugar (TF = 3 mg/d). Treatments were matched for total fat, saturated fat, carbohydrates and protein. The cocoa treatment significantly increased the basal diameter and peak diameter of the brachial artery by 6% (+2 mm) and basal blood flow volume by 22%. Substantial decreases in the AI, a measure of arterial stiffness, were observed in only women. Flow-mediated dilation and the reactive hyperaemia index remained unchanged. The consumption of cocoa had no effect on fasting blood measures, while the control treatment increased fasting insulin concentration and insulin resistance (P= 0·01). Fasting blood pressure (BP) remained unchanged, although the acute consumption of cocoa increased resting BP by 4 mmHg. In summary, the high-flavanol cocoa and dark chocolate treatment was associated with enhanced vasodilation in both conduit and resistance arteries and was accompanied by significant reductions in arterial stiffness in women.

TRPV1 channels in human skeletal muscle feed arteries: implications for vascular function.

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Ives, Stephen J; Park, Song Young; Kwon, Oh Sung; Gifford, Jayson R; Andtbacka, Robert H I; Hyngstrom, John R; Richardson, Russell S

2017-09-01

What is the central question of this study? We sought to determine whether human skeletal muscle feed arteries (SFMAs) express TRPV 1 channels and what role they play in modulating vascular function. What is the main finding and its importance? Human SMFAs do express functional TRPV 1 channels that modulate vascular function, specifically opposing α-adrenergic receptor-mediated vasocontraction and potentiating vasorelaxation, in an endothelium-dependent manner, as evidenced by the α 1 -receptor-mediated responses. Thus, the vasodilatory role of TRPV 1 channels, and their ligand capsaicin, could be a potential therapeutic target for improving vascular function. Additionally, given the 'sympatholytic' effect of TRPV 1 activation and known endogenous activators (anandamide, reactive oxygen species, H + , etc.), TRPV 1 channels might contribute to functional sympatholysis during exercise. To examine the role of the transient receptor potential vanilloid type 1 (TRPV 1 ) ion channel in the vascular function of human skeletal muscle feed arteries (SMFAs) and whether activation of this heat-sensitive receptor could be involved in modulating vascular function, SMFAs from 16 humans (63 ± 5 years old, range 41-89 years) were studied using wire myography with capsaicin (TRPV 1 agonist) and without (control). Specifically, phenylephrine (α 1 -adrenergic receptor agonist), dexmedetomidine (α 2 -adrenergic receptor agonist), ACh and sodium nitroprusside concentration-response curves were established to assess the role of TRPV 1 channels in α-receptor-mediated vasocontraction as well as endothelium-dependent and -independent vasorelaxation, respectively. Compared with control conditions, capsaicin significantly attenuated maximal vasocontraction in response to phenylephrine [control, 52 ± 8% length-tension max (LT max ) and capsaicin, 21 ± 5%LT max ] and dexmedetomidine (control, 29 ± 12%LT max and capsaicin, 2 ± 3%LT max ), while robustly enhancing maximal

Carotid Artery Intima-Media Thickness and Cutaneous Microvascular Function are Associated With Vitamin C Levels in Young Patients With Type 1 Diabetes

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Odermarsky, Michal; Lykkesfeldt, Jens; Liuba, Petru

2008-01-01

Background: Vascular endothelial dysfunction and accelerated thickening of arterial intima contribute to increased cardiovascular morbidity in type 1 diabetes. Although vitamin C has important antioxidant functions, and increased oxidative stress is a central mechanism of vascular abnormalities......, lower plasma levels of vitamin C appears to predispose to more pronounced adverse changes in both microcirculation and peripheral arteries. Further studies are needed to investigate whether dietary supplementation with vitamin C could retard the development of microvasculopathy and atherosclerosis...... in diabetes, the relationship between these two in young patients with this disease has not been yet investigated. Methods: Carotid artery intima-media thickness (cIMT) and cutaneous microvascular reactivity to endothelium-dependent (acetylcholine, ACH) and independent (sodium nitroprusside, SNP) were...

Arterial Ventricular Uncoupling with Age and Disease and Recoupling with Exercise

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Chantler, Paul D

2017-01-01

The deterioration in arterial and cardiac function with aging impairs arterial ventricular coupling, an important determinant of cardiovascular performance. However, exercise training improves arterial ventricular coupling especially during exercise during the age and disease process. This review examines the concept of arterial-ventricular coupling, and how age, and disease uncouples but exercise training recouples the heart and arterial system. PMID:28072585

Dark chocolate and vascular function in patients with peripheral artery disease: a randomized, controlled cross-over trial.

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Hammer, Alexandra; Koppensteiner, Renate; Steiner, Sabine; Niessner, Alexander; Goliasch, Georg; Gschwandtner, Michael; Hoke, Matthias

2015-01-01

Flavonoid-rich dark chocolate has positive effects on vascular function in healthy subjects and in patients at risk of atherosclerosis. The impact of dark chocolate on endothelial and microvascular function in patients with symptomatic peripheral artery disease (PAD) has not been investigated so far. In an investigator blinded, randomized, controlled, cross-over trial we assessed the effect of flavonoid-rich dark chocolate and cocoa-free control chocolate on flow-mediated dilatation (FMD) of the brachial artery and on microvascular function (assessed by Laser Doppler fluxmetry) in 21 patients with symptomatic (Fontaine stage II) PAD. Measurements were done in each patient on 2 single days, with an interval of 7 days, at baseline and at 2 hours after ingestion of 50 g dark chocolate or 50 g white chocolate, respectively. FMD remained unchanged after intake of dark chocolate (baseline and 2 hours after ingestion, %: 5.1 [IQR 4.4 to 7.3] and 5.5 [IQR 3.9 to 10.4]; p = 0.57, and after intake of white chocolate (baseline and 2 hours after ingestion, %: 6.4 [IQR 4.5 to 11.4] and 4.4 [IQR 2.6 to 8.7]; p = 0.14. Similarly, microcirculatory parameters were not significantly altered after intake of any chocolate compared with the respective baseline values. In conclusion, a single consumption of 50 g dark chocolate has no effect on endothelial and microvascular function in patients with symptomatic PAD.

Relation between respiratory function and arterial stiffness assessed using brachial-ankle pulse wave velocity in healthy workers.

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Inomoto, Atsushi; Fukuda, Rika; Deguchi, Junko; Toyonaga, Toshihiro

2017-09-01

[Purpose] Current studies report that patients with chronic obstructive pulmonary disease (COPD) may also have arteriosclerosis. This study aimed to investigate the relationship between respiratory function and arterial stiffness in healthy workers using the brachial-ankle pulse wave velocity (baPWV). [Subjects and Methods] This study included 104 male Japanese workers without COPD. We collected participant information and measured hemodynamics, body composition, and respiratory function. [Results] In the correlation analysis, baPWV showed a significant positive correlation with age, smoking index, systolic blood pressure, diastolic blood pressure, and heart rate, and a significant negative correlation with height, fat free mass, lower limb muscle mass, forced vital capacity (FVC), and forced expiratory volume in one second (FEV1). In multiple regression analysis using factors other than baPWV and respiratory function as adjustment variables, both FVC and FEV1 showed a significant negative relationship with baPWV (p=0.009 and p=0.027, respectively). FEV1/FVC was not significantly related to baPWV (p=0.704). [Conclusion] The results of this study indicated that FEV1/FVC and the proportion of FEV1 predicted, which are indicators of airflow limitation, are not predictors of baPWV in workers without airflow limitation. However, since baPWV showed a significant negative relationship with FVC and FEV 1, the reduction in respiratory function that does not cause airflow limitation, such as FVC or FEV1 decline, may be related to an increase in the risk of arterial stiffness.

Respiratory muscle stretch gymnastics in patients with post coronary artery bypass grafting pain : Impact on respiratory muscle function, activity, mood and exercise capacity

OpenAIRE

會田, 信子; 渋谷, 優子; 吉野, 克樹; Komoda, Masaji; 井上, 智子

2002-01-01

A new rehabilitation (New-RH) program including respiratory muscle stretch gymnastics (RMSG) was developed to alleviate post-coronary artery bypass grafting pain (PCP). Effects on respiratory muscle function, pain, activities of daily living (ADL), mood and exercise capacity were investigated. Subjects were 16 consecutive patients undergoing median full sternotomy coronary artery bypass grafting (CABG), and were randomly divided into equal New-RH (S-group) and conventional therapy (C-group) g...

Functional real-time optoacoustic imaging of middle cerebral artery occlusion in mice.

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Moritz Kneipp

Full Text Available BACKGROUND AND PURPOSE: Longitudinal functional imaging studies of stroke are key in identifying the disease progression and possible therapeutic interventions. Here we investigate the applicability of real-time functional optoacoustic imaging for monitoring of stroke progression in the whole brain of living animals. MATERIALS AND METHODS: The middle cerebral artery occlusion (MCAO was used to model stroke in mice, which were imaged preoperatively and the occlusion was kept in place for 60 minutes, after which optoacoustic scans were taken at several time points. RESULTS: Post ischemia an asymmetry of deoxygenated hemoglobin in the brain was observed as a region of hypoxia in the hemisphere affected by the ischemic event. Furthermore, we were able to visualize the penumbra in-vivo as a localized hemodynamically-compromised area adjacent to the region of stroke-induced perfusion deficit. CONCLUSION: The intrinsic sensitivity of the new imaging approach to functional blood parameters, in combination with real time operation and high spatial resolution in deep living tissues, may see it become a valuable and unique tool in the development and monitoring of treatments aimed at suspending the spread of an infarct area.

The anterior cerebral artery is an appropriate arterial input function for perfusion-CT processing in patients with acute stroke

International Nuclear Information System (INIS)

Wintermark, Max; Lau, Benison C.; Chien, Jeffrey; Arora, Sandeep

2008-01-01

Dynamic perfusion-CT (PCT) with deconvolution requires an arterial input function (AIF) for postprocessing. In clinical settings, the anterior cerebral artery (ACA) is often chosen for simplicity. The goals of this study were to determine how the AIF selection influences PCT results in acute stroke patients and whether the ACA is an appropriate default AIF. We retrospectively identified consecutive patients suspected of hemispheric stroke of less than 48 h duration who were evaluated on admission by PCT. PCT datasets were postprocessed using multiple AIF, and cerebral blood volume (CBV) and flow (CBF), and mean transit time (MTT) values were measured in the corresponding territories. Results from corresponding territories in the same patients were compared using paired t-tests. The volumes of infarct core and tissue at risk obtained with different AIFs were compared to the final infarct volume. Of 113 patients who met the inclusion criteria, 55 with stroke were considered for analysis. The MTT values obtained with an ''ischemic'' AIF tended to be shorter (P=0.055) and the CBF values higher (P=0.108) than those obtained using a ''nonischemic'' AIF. CBV values were not influenced by the selection of the AIF. No statistically significant difference was observed between the size of the PCT infarct core (P=0.121) and tissue at risk (P=0.178), regardless of AIF selection. In acute stroke patients, the selection of the AIF has no statistically significant impact of the PCT results; standardization of the PCT postprocessing using the ACA as the default AIF is adequate. (orig.)

Computer-assisted 3D reconstruction of the terminal branches of th cerebral arteries. Pt. 2. Middle cerebral artery

International Nuclear Information System (INIS)

Gloger, S.; Gloger, A.; Vogt, H.; Kretschmann, H.J.

1994-01-01

We present a three-dimensional anatomical computer model of the terminal branches of the middle cerebral artery, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries, which can help to identify them on conventional angiography and magnetic resonance angiography. The arteries can also be matched with CT, MR or PET images to indicate the areas of extension of individual branches, allowing neuromorphological and functional correlations. (orig.)

Computer-assisted 3D reconstruction of the terminal branches of th cerebral arteries. Pt. 2. Middle cerebral artery

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Gloger, S. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Gloger, A. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Vogt, H. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Kretschmann, H.J. (Dept. of Neuroanatomy, Hannover Medical School (Germany))

1994-04-01

We present a three-dimensional anatomical computer model of the terminal branches of the middle cerebral artery, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries, which can help to identify them on conventional angiography and magnetic resonance angiography. The arteries can also be matched with CT, MR or PET images to indicate the areas of extension of individual branches, allowing neuromorphological and functional correlations. (orig.)

Interventional therapy of atherosclerotic renal artery occlusion

International Nuclear Information System (INIS)

Li Jian; Xu Ke; Xiao Liang

2009-01-01

Objective: To investigate the effectiveness of interventional therapy for the atherosclerotic renal artery occlusion (ARAO). Methods: During the period of June 2001-Dec. 2007, 16 patients with ARAO (total of 16 occluded arteries) underwent interventional managements, including percutaneous endovascular renal artery revascularization, balloon dilatation angioplasty and stent placement. Follow-up survey was made at regular intervals. The patent condition of the renal artery was evaluated with ultrasonography and digital subtraction angiography. The blood pressure and the renal function were determined and the data were statistically analyzed in order to assess the intermediate and long-term effect of the interventional therapy. Results: Of 16 patients, technical success was achieved in 15 (93.8%) and failure occurred in one. During a follow-up period of 9 - 24 months, 3 patients died. According to the data obtained at each patient's last follow-up survey, the hypertension fell to normal in 3 (25.0%), was improved in 7 (58.3%) and showed no marked change in 2 patients (16.7%), with a clinical efficacy of 83.3% (10 / 12). The renal function was improved in 2 (16.7%), stabilized in 6 (50%) and deteriorated in 4 patients (33.3%), with an effective rate of 66.7% (8 / 12). Conclusion: For the treatment of atherosclerotic renal artery occlusion, the interventional therapy carries high successful rate and can effectively lower the blood pressure level, in addition, it can also protect the renal function in a certain degree. (authors)

Left ventricular diastolic function in patients with coronary artery disease

International Nuclear Information System (INIS)

Brugger, P.T.

1986-01-01

In 302 patients with confirmed coronary disease we determined the left ventricular diastolic function with the Nuclear Stethoscope by the aid of the Peak Filling Rate (PFR) and the Time to Peak Filling Rate (TPFR). Moreover we investigated the ejection fraction (EF). 201 patients had already suffered a myocardial infarction, of these 99 an anterior wall and 102 an inferior wall infarction. The remaining 101 patients had a CAD without a history of myocardial infarction. The PFR was 2.19 ± 0.65 EDV/sec in the 99 patients after anterior wall infarction and 2.62 ± 0.85 EDV/sec in the 102 patients after inferior wall infarction and 2.79 ± 0.85 EDV/sec in 101 patients with coronary artery disease without a history of myocardial infarction. For the PFR there could be found a statistically significant difference between normal patients and patients after anterior wall infarction (p [de

Measurement of brachial artery endothelial function using a standard blood pressure cuff

International Nuclear Information System (INIS)

Maltz, Jonathan S; Budinger, Thomas F; Tison, Geoffrey H; Olgin, Jeffrey; Alley, Hugh F; Owens, Christopher D

2015-01-01

The integrity of endothelial function in major arteries (EFMA) is a powerful independent predictor of heart attack and stroke. Existing ultrasound-based non-invasive assessment methods are technically challenging and suitable only for laboratory settings. EFMA, like blood pressure (BP), is both acutely and chronically affected by factors such as lifestyle and medication. Consequently, laboratory-based measurements cannot fully gauge the effects of medical interventions on EFMA. EFMA and BP have, arguably, comparable (but complementary) value in the assessment of cardiovascular health. Widespread deployment of EFMA assessment is thus a desirable clinical goal. To this end, we propose a device based on modifying the measurement protocol of a standard electronic sphygmomanometer. The protocol involves inflating the cuff to sub-diastolic levels to enable recording of the pulse waveform before and after vasodilatory stimulus. The mechanical unloading of the arterial wall provided by the cuff amplifies the distension that occurs with each pulse, which is measured as a pressure variation in the cuff. We show that the height of the rising edge of each pulse is proportional to the change in lumen area between diastole and systole. This allows the effect of vasodilatory stimuli on the artery to be measured with high sensitivity. We compare the proposed cuff flow-mediated dilation (cFMD) method to ultrasound flow-mediated dilation (uFMD). We find significant correlation (r  =  0.55, p  =0.003, N  =  27) between cFMD- and uFMD-based metrics obtained when the release of a 5 min cuff occlusion is employed to induce endothelial stimulus via reactive hyperemia. cFMD is approximately proportional to the square of uFMD, representing a typical increase in sensitivity to vasodilation of 300–600%. This study illustrates the potential for an individual to conveniently measure his/her EFMA by using a low-cost reprogrammed home sphygmomanometer. (paper)

High-NaCl diet impairs dynamic renal blood flow autoregulation in rats with adenine-induced chronic renal failure.

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Saeed, Aso; DiBona, Gerald F; Grimberg, Elisabeth; Nguy, Lisa; Mikkelsen, Minne Line Nedergaard; Marcussen, Niels; Guron, Gregor

2014-03-15

This study examined the effects of 2 wk of high-NaCl diet on kidney function and dynamic renal blood flow autoregulation (RBFA) in rats with adenine-induced chronic renal failure (ACRF). Male Sprague-Dawley rats received either chow containing adenine or were pair-fed an identical diet without adenine (controls). After 10 wk, rats were randomized to either remain on the same diet (0.6% NaCl) or to be switched to high 4% NaCl chow. Two weeks after randomization, renal clearance experiments were performed under isoflurane anesthesia and dynamic RBFA, baroreflex sensitivity (BRS), systolic arterial pressure variability (SAPV), and heart rate variability were assessed by spectral analytical techniques. Rats with ACRF showed marked reductions in glomerular filtration rate and renal blood flow (RBF), whereas mean arterial pressure and SAPV were significantly elevated. In addition, spontaneous BRS was reduced by ∼50% in ACRF animals. High-NaCl diet significantly increased transfer function fractional gain values between arterial pressure and RBF in the frequency range of the myogenic response (0.06-0.09 Hz) only in ACRF animals (0.3 ± 4.0 vs. -4.4 ± 3.8 dB; P renal failure by facilitating pressure transmission to the microvasculature.

Randomized controlled trial to evaluate the effect of canola oil on blood vessel function in peripheral arterial disease: rationale and design of the Canola-PAD Study

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Enns JE

2014-10-01

Full Text Available Jennifer E Enns,1,2 Peter Zahradka,1–3 Randolph P Guzman,4,5 Alanna Baldwin,1 Brendon Foot,1 Carla G Taylor1–31Canadian Centre for Agri-Food Research in Health and Medicine, St Boniface Research Centre, Winnipeg, Canada; 2Department of Physiology, University of Manitoba, Winnipeg, Manitoba, Canada; 3Department of Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada; 4IH Asper Clinical Research Institute, St Boniface Hospital, Winnipeg, Canada; 5Section of Vascular Surgery, Department of Surgery, St Boniface Hospital, Winnipeg, CanadaBackground: Individuals with peripheral arterial disease (PAD are at high risk for cardiac events due to atherosclerosis. Dietary fatty acid composition has been shown to modulate blood vessel properties, but whether a diet enriched in conventional canola oil can improve clinical endpoints in PAD is not known.Purpose: To describe the rationale and design of a clinical trial testing the effect of canola oil consumption on vascular function and cardiovascular risk factors in an 8-week dietary intervention in individuals with PAD.Methods: The Canola-PAD Study was a single center, prospective, double-blind, randomized controlled trial in 50 patients over 40 years old with PAD. Participants were randomized into two groups and consumed food items containing either conventional canola oil (25 g/day or an oil mixture representing the Western diet (25 g/day for 8 weeks as part of their usual diet. The primary outcome was vascular function (ankle-brachial index, arterial stiffness, endothelial dysfunction, walking capacity, and cognitive function. Secondary measurements included anthropometrics, serum lipid profile and fatty acid composition, markers of inflammation and glycemic control, and serum metabolite profile.Discussion: The Canola-PAD Study uses an innovative and noninvasive approach to evaluate the effect of canola oil on clinically relevant outcomes in individuals with PAD, including

Left ventricular diastolic function in type 2 diabetes mellitus and the association with coronary artery calcium score: a cardiac MRI study.

Science.gov (United States)

Graça, Bruno; Donato, Paulo; Ferreira, Maria João; Castelo-Branco, Miguel; Caseiro-Alves, Filipe

2014-06-01

The purpose of this study was to compare cardiac MRI-derived parameters of left ventricular (LV) diastolic function between uncomplicated type 2 diabetes mellitus (DM2) and normoglycemic control subjects and to evaluate whether these parameters of LV diastolic function are related to coronary atherosclerosis. We prospectively studied 41 subjects with DM2 and 21 normoglycemic control subjects (30 women and 32 men; mean age, 57.2 ± 7.1 [SD] years) with no evidence of overt cardiovascular disease. We used cardiac MRI to measure LV volumes, LV peak filling rate (PFR), and transmitral flow and CT to determine coronary artery calcium scores. Absolute values of the peak filling rate (PFR) were significantly lower in DM2 patients than in control subjects (mean ± SD, 293.2 ± 51.7 vs 375.7 ± 102.8 mL/s, respectively; p DM2 patients compared with control subjects. DM2 patients with coronary artery calcification showed a lower PFR normalized to stroke volume (SV) (mean ± SD, 4.4 ± 1.0 vs 5.3 ± 1.4, respectively; p = 0.038) and lower mitral peak E velocities (40.1 ± 11.3 vs 48.0 ± 7.3 cm/s; p = 0.024) than DM2 patients without coronary calcification. PFR normalized to SV was independently associated with the presence of coronary artery calcification (β = -1.5, p = 0.005). DM2 decreases cardiovascular MRI-derived parameters of LV diastolic function. Patients with DM2 and coronary atherosclerosis show a more impaired LV diastolic function than patients without coronary atherosclerosis.

Mechanical design in arteries.

Science.gov (United States)

Shadwick, R E

1999-12-01

The most important mechanical property of the artery wall is its non-linear elasticity. Over the last century, this has been well-documented in vessels in many animals, from humans to lobsters. Arteries must be distensible to provide capacitance and pulse-smoothing in the circulation, but they must also be stable to inflation over a range of pressure. These mechanical requirements are met by strain-dependent increases in the elastic modulus of the vascular wall, manifest by a J-shaped stress-strain curve, as typically exhibited by other soft biological tissues. All vertebrates and invertebrates with closed circulatory systems have arteries with this non-linear behaviour, but specific tissue properties vary to give correct function for the physiological pressure range of each species. In all cases, the non-linear elasticity is a product of the parallel arrangement of rubbery and stiff connective tissue elements in the artery wall, and differences in composition and tissue architecture can account for the observed variations in mechanical properties. This phenomenon is most pronounced in large whales, in which very high compliance in the aortic arch and exceptionally low compliance in the descending aorta occur, and is correlated with specific modifications in the arterial structure.

Pleurotomy with subxyphoid pleural drain affords similar effects to pleural integrity in pulmonary function after off-pump coronary artery bypass graft

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Guizilini Solange

2012-01-01

Full Text Available Abstract Background Exacerbation of pulmonary dysfunction has been reported in patients receiving a pleural drain inserted through the intercostal space in comparison to patients with an intact pleura undergoing coronary artery bypass grafting (CABG. Evidence suggests that shifting the site of pleural drain insertion to the subxyphoid position minimizes chest wall trauma and preserves respiratory function in the early postoperative period. The aim of this study was to compare the pulmonary function parameters, clinical outcomes, and pain score between patients undergoing pleurotomy with pleural drain placed in the subxyphoid position and patients with intact pleural cavity after off-pump CABG (OPCAB using left internal thoracic artery (LITA. Methods Seventy-one patients were allocated into two groups: I (n = 38 open left pleural cavity and pleural drain inserted in the subxyphoid position; II (n = 33 intact pleural cavity. Pulmonary function tests and clinical parameters were recorded preoperatively and on postoperative days (POD 1, 3 and 5. Arterial blood gas analysis and shunt fraction were evaluated preoperatively and in POD1. Pain score was assessed on POD1. To monitor pleural effusion and atelectasis chest radiography was performed routinely 1 day before operation and until POD5. Results In both groups a significant impairment was found in lung function parameters until on POD5. However, no significant difference in forced vital capacity and forced expiratory volume in 1 second were seen between groups. A significant decrease in partial pressure of arterial oxygen and an increase in shunt fraction values were observed on POD1 in both groups, but no statistical difference was found when the groups were compared. Pleural effusion and atelectasis until on POD5 were similar in both groups. There were no statistical differences in pain score, duration of mechanical ventilation and postoperative hospital stay between groups. Conclusion Subxyphoid

Interesting images: Multiple coronary artery aneurysms.

Science.gov (United States)

Howard, Jonathon M; Viswanath, Omar; Armas, Alfredo; Santana, Orlando; Rosen, Gerald P

2017-01-01

We present the case of a 65-year-old male who presented with stable angina and dyspnea on exertion. His initial workup yielded a positive treadmill stress test for reversible apical ischemia, and transthoracic echocardiogram demonstrated impaired systolic function. Cardiac catheterization was then performed, revealing severe atherosclerotic disease including multiple coronary artery aneurysms. As a result, the patient was advised to and subsequently underwent a coronary artery bypass graft. This case highlights the presence of multiple coronary artery aneurysms and the ability to appreciate these pathologic findings on multiple imaging modalities, including coronary angiogram, transesophageal echocardiography, and direct visualization through the surgical field.

Differential anti-ischaemic effects of muscarinic receptor blockade in patients with obstructive coronary artery disease; impaired vs normal left ventricular function.

NARCIS (Netherlands)

A.F. van den Heuvel; D.J. van Veldhuisen (Dirk); G.L. Bartels; M. van der Ent (Martin); W.J. Remme (Willem)

1999-01-01

textabstractAIMS: In patients with coronary artery disease acetylcholine (a muscarinic agonist) causes vasoconstriction. The effect of atropine (a muscarinic antagonist) on coronary vasotone in patients with normal or impaired left ventricular function is unknown.

Pathophysiological Features of Endogenous Intoxication in Pregnant Women with Arterial Hypertension

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N. V. Kabanova

2008-01-01

Full Text Available Objective: to determine the nature and specific features of development of endogenous intoxication in pregnant women with arterial hypertension. Subjects and materials. Humoral extracellular fluid volume regulation, partial renal functions, placental hormonal function, membranous lipid peroxidation activity, antiradical defense, the parameters of central hemodynamics, endogenous intoxication, and a biochemical coagulogram were studied and differential blood count with the leukocytic ratio indices was estimated in 172 pregnant females with arterial hypertension and 54 healthy pregnant ones in the third trimester. The statistical package «Stadia» was applied. Results. Arterial hypertension caused by pregnancy was ascertained to involve pathogenetically different types: low-, normal-, and high-renin ones. In pregnant women with arterial hypertension, the general pathogenetic homeostatic changes were placental hormonal imbalance, activated membranous lipid peroxidation, impaired lymph outflow, sodium and water retention, hepatic and renal failure, and endogenous intoxication. Conclusion. Placental ischemia appearing as placental hormonal imbalance (extrarenal pressor system was accompanied by a compensatory humoral response: arterial hypertension and metabolic disturbances. Changes in medium-weight molecule 280, leukocytic intoxication index, erythrocytic sorption capacity, and Paramecium test, by confirming the presence of endogenous intoxication in pregnant females with arterial hypertension, were caused by a type of arterial hypertension (by the hemodynamic profile and the type of impaired partial renal functions. Key words: pregnancy, arterial hypertension, endogenous intoxication.

A new diagnostic approach to popliteal artery entrapment syndrome

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Williams, Charles; Kennedy, Dominic; Bastian-Jordan, Matthew; Hislop, Matthew; Cramp, Brendan; Dhupelia, Sanjay [Queensland X-Ray, Sunnybank, Queensland, 4109 (Australia)

2015-09-15

A new method of diagnosing and defining functional popliteal artery entrapment syndrome is described. By combining ultrasonography and magnetic resonance imaging techniques with dynamic plantarflexion of the ankle against resistance, functional entrapment can be demonstrated and the location of the arterial occlusion identified. This combination of imaging modalities will also define muscular anatomy for guiding intervention such as surgery or Botox injection.

A new diagnostic approach to popliteal artery entrapment syndrome

International Nuclear Information System (INIS)

Williams, Charles; Kennedy, Dominic; Bastian-Jordan, Matthew; Hislop, Matthew; Cramp, Brendan; Dhupelia, Sanjay

2015-01-01

A new method of diagnosing and defining functional popliteal artery entrapment syndrome is described. By combining ultrasonography and magnetic resonance imaging techniques with dynamic plantarflexion of the ankle against resistance, functional entrapment can be demonstrated and the location of the arterial occlusion identified. This combination of imaging modalities will also define muscular anatomy for guiding intervention such as surgery or Botox injection

The Effect of Endovascular Revascularization of Common Iliac Artery Occlusions on Erectile Function

International Nuclear Information System (INIS)

Gur, Serkan; Ozkan, Uğur; Onder, Hakan; Tekbas, Güven; Oguzkurt, Levent

2013-01-01

To determine the incidence of erectile dysfunction in patients with common iliac artery (CIA) occlusive disease and the effect of revascularization on erectile function using the sexual health inventory for males (SHIM) questionnaire. All patients (35 men; mean age 57 ± 5 years; range 42–67 years) were asked to recall their sexual function before and 1 month after iliac recanalization. Univariate and multivariate analyses were performed to determine variables effecting improvement of impotence. The incidence of impotence in patients with CIA occlusion was 74% (26 of 35) preoperatively. Overall 16 (46%) of 35 patients reported improved erectile function after iliac recanalization. The rate of improvement of impotence was 61.5% (16 of 26 impotent patients). Sixteen patients (46%), including seven with normal erectile function before the procedure, had no change. Three patients (8%) reported deterioration of their sexual function, two of whom (6%) had normal erectile function before the procedure. The median SHIM score increased from 14 (range 4–25) before the procedure to 20 (range 1–25) after the procedure (P = 0.005). The type of recanalization, the age of the patients, and the length of occlusion were related to erectile function improvement in univariate analysis. However, these factors were not independent factors for improvement of erectile dysfunction in multivariate analysis (P > 0.05). Endovascular recanalization of CIA occlusions clearly improves sexual function. More than half of the patients with erectile dysfunction who underwent endovascular recanalization of the CIA experienced improvement.

The Effect of Endovascular Revascularization of Common Iliac Artery Occlusions on Erectile Function

Energy Technology Data Exchange (ETDEWEB)

Gur, Serkan, E-mail: mserkangur@yahoo.com [Sifa Hospital, Department of Radiology (Turkey); Ozkan, Ugur [Baskent University, Department of Radiology, Faculty of Medicine (Turkey); Onder, Hakan; Tekbas, Gueven [Dicle University, Department of Radiology, Faculty of Medicine (Turkey); Oguzkurt, Levent [Baskent University, Department of Radiology, Faculty of Medicine (Turkey)

2013-02-15

To determine the incidence of erectile dysfunction in patients with common iliac artery (CIA) occlusive disease and the effect of revascularization on erectile function using the sexual health inventory for males (SHIM) questionnaire. All patients (35 men; mean age 57 {+-} 5 years; range 42-67 years) were asked to recall their sexual function before and 1 month after iliac recanalization. Univariate and multivariate analyses were performed to determine variables effecting improvement of impotence. The incidence of impotence in patients with CIA occlusion was 74% (26 of 35) preoperatively. Overall 16 (46%) of 35 patients reported improved erectile function after iliac recanalization. The rate of improvement of impotence was 61.5% (16 of 26 impotent patients). Sixteen patients (46%), including seven with normal erectile function before the procedure, had no change. Three patients (8%) reported deterioration of their sexual function, two of whom (6%) had normal erectile function before the procedure. The median SHIM score increased from 14 (range 4-25) before the procedure to 20 (range 1-25) after the procedure (P = 0.005). The type of recanalization, the age of the patients, and the length of occlusion were related to erectile function improvement in univariate analysis. However, these factors were not independent factors for improvement of erectile dysfunction in multivariate analysis (P > 0.05). Endovascular recanalization of CIA occlusions clearly improves sexual function. More than half of the patients with erectile dysfunction who underwent endovascular recanalization of the CIA experienced improvement.

Simultaneous acquisition of dynamic PET-MRI: arterial input function using DSC-MRI and [18F]-FET

Energy Technology Data Exchange (ETDEWEB)

Caldeira, Liliana; Yun, Seong Dae; Silva, Nuno da; Filss, Christian; Scheins, Juergen; Telmann, Lutz; Herzog, Hans; Shah, Jon [Institute of Neuroscience and Medicine - 4, Forschungszentrum Juelich GmbH (Germany)

2015-05-18

This work focuses on the study of simultaneous dynamic MR-PET acquisition in brain tumour patients. MR-based perfusion-weighted imaging (PWI) and PET [18F]-FET are dynamic methods, which allow to evaluate tumour metabolism in a quantitative way. In both methods, arterial input function (AIF) is necessary for quantification. However, the AIF estimation is a challenging task. In this work, we explore the possibilities to combine dynamic MR and PET AIF.

Simultaneous acquisition of dynamic PET-MRI: arterial input function using DSC-MRI and [18F]-FET

International Nuclear Information System (INIS)

Caldeira, Liliana; Yun, Seong Dae; Silva, Nuno da; Filss, Christian; Scheins, Juergen; Telmann, Lutz; Herzog, Hans; Shah, Jon

2015-01-01

This work focuses on the study of simultaneous dynamic MR-PET acquisition in brain tumour patients. MR-based perfusion-weighted imaging (PWI) and PET [18F]-FET are dynamic methods, which allow to evaluate tumour metabolism in a quantitative way. In both methods, arterial input function (AIF) is necessary for quantification. However, the AIF estimation is a challenging task. In this work, we explore the possibilities to combine dynamic MR and PET AIF.

Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 1. Anterior cerebral artery

International Nuclear Information System (INIS)

Gloger, S.; Gloger, A.; Vogt, H.; Kretschmann, H.J.

1994-01-01

We present a three-dimensional anatomical computer model of the terminal branches of the anterior cerebral artery, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries, which can help to identify them on conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can also be matched with CT, MR or PET images to indicate the areas of extension of individual branches, allowing neuromorphological and functional correlation. (orig.)

Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 1. Anterior cerebral artery

Energy Technology Data Exchange (ETDEWEB)

Gloger, S. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Gloger, A. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Vogt, H. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Kretschmann, H.J. (Dept. of Neuroanatomy, Hannover Medical School (Germany))

1994-04-01

We present a three-dimensional anatomical computer model of the terminal branches of the anterior cerebral artery, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries, which can help to identify them on conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can also be matched with CT, MR or PET images to indicate the areas of extension of individual branches, allowing neuromorphological and functional correlation. (orig.)

The Impact of Carotid Artery Stenting on Cerebral Perfusion, Functional Connectivity, and Cognition in Severe Asymptomatic Carotid Stenosis Patients

Directory of Open Access Journals (Sweden)

Tao Wang

2017-08-01

Full Text Available Background and purposeAsymptomatic carotid artery stenosis can lead to not only stroke but also cognition impairment. Although it has been proven that carotid artery stenting (CAS can reduce the risk of future strokes, the effect of CAS on cognition is conflicting. In recent years, pulsed arterial spin labeling (pASL MRI and resting-state functional MRI (R-fMRI have been employed in cognitive impairment studies. For the present study, cognition is evaluated in severe asymptomatic carotid artery stenosis patients undergoing CAS, and the mechanisms underlying the cognitive change are explored by pASL MRI and R-fMRI.Materials and methodsWe prospectively enrolled 24 asymptomatic, severe (≥70%, unilateral internal carotid artery stenosis patients, who were expecting the intervention of CAS. Cognition assessment (including the Montreal Cognitive Assessment Beijing Version, the Minimum Mental State Examination, the Digit Symbol Test, the Rey Auditory Verbal Learning Test, and the Verbal Memory Test and an integrated MRI program (pASL MRI, and R-fMRI were administered 7 days before and 3 months after CAS.Results16 subjects completed the follow-up study. After stenting, significant improvement in the scores of the MMSE, the Verbal Memory test, and the delayed recall was found. No significant difference was found in the scores of the Montreal Cognitive Assessment Beijing Version, the Digit Symbol Test, and the immediate recall. After CAS treatment, asymptomatic carotid artery stenosis patients showed increased perfusion in the left frontal gyrus, increased amplitude of low-frequency fluctuation (ALFF in the right precentral gyrus, and increased connectivity to the posterior cingulate cortex (PCC in the right supra frontal gyrus. However, no significant correlations were found between these imaging changes and cognition assessments.ConclusionSuccessful CAS can partly improve cognition in asymptomatic carotid artery stenosis patients. The cognition

Spatial differences of cellular origins and in vivo hypoxia modify contractile properties of pulmonary artery smooth muscle cells: lessons for arterial tissue engineering.

Science.gov (United States)

Hall, S M; Soueid, A; Smith, T; Brown, R A; Haworth, S G; Mudera, V

2007-01-01

Tissue engineering of functional arteries is challenging. Within the pulmonary artery wall, smooth muscle cells (PASMCs) have site-specific developmental and functional phenotypes, reflecting differing contractile roles. The force generated by PASMCs isolated from the inner 25% and outer 50% of the media of intrapulmonary elastic arteries from five normal and eight chronically hypoxic (hypertensive) 14 day-old piglets was quantified in a three-dimensional (3D) collagen construct, using a culture force monitor. Outer medial PASMCs from normal piglets exerted more force (528 +/- 50 dynes) than those of hypoxic piglets (177 +/- 42 dynes; p engineering of major blood vessels.

Arterial stiffness and cognitive impairment.

Science.gov (United States)

Li, Xiaoxuan; Lyu, Peiyuan; Ren, Yanyan; An, Jin; Dong, Yanhong

2017-09-15

Arterial stiffness is one of the earliest indicators of changes in vascular wall structure and function and may be assessed using various indicators, such as pulse-wave velocity (PWV), the cardio-ankle vascular index (CAVI), the ankle-brachial index (ABI), pulse pressure (PP), the augmentation index (AI), flow-mediated dilation (FMD), carotid intima media thickness (IMT) and arterial stiffness index-β. Arterial stiffness is generally considered an independent predictor of cardiovascular and cerebrovascular diseases. To date, a significant number of studies have focused on the relationship between arterial stiffness and cognitive impairment. To investigate the relationships between specific arterial stiffness parameters and cognitive impairment, elucidate the pathophysiological mechanisms underlying the relationship between arterial stiffness and cognitive impairment and determine how to interfere with arterial stiffness to prevent cognitive impairment, we searched PUBMED for studies regarding the relationship between arterial stiffness and cognitive impairment that were published from 2000 to 2017. We used the following key words in our search: "arterial stiffness and cognitive impairment" and "arterial stiffness and cognitive impairment mechanism". Studies involving human subjects older than 30years were included in the review, while irrelevant studies (i.e., studies involving subjects with comorbid kidney disease, diabetes and cardiac disease) were excluded from the review. We determined that arterial stiffness severity was positively correlated with cognitive impairment. Of the markers used to assess arterial stiffness, a higher PWV, CAVI, AI, IMT and index-β and a lower ABI and FMD were related to cognitive impairment. However, the relationship between PP and cognitive impairment remained controversial. The potential mechanisms linking arterial stiffness and cognitive impairment may be associated with arterial pulsatility, as greater arterial pulsatility

Cardiac MRI in pulmonary artery hypertension: correlations between morphological and functional parameters and invasive measurements

Energy Technology Data Exchange (ETDEWEB)

Alunni, Jean-Philippe; Otal, Philippe; Rousseau, Herve; Chabbert, Valerie [CHU Rangueil, Department of Radiology, Toulouse (France); Degano, Bruno; Tetu, Laurent; Didier, Alain [CHU Larrey, Department of Pneumology, Toulouse (France); Arnaud, Catherine [CHU Rangueil, Department of Methods in Clinical Research, Toulouse (France); Blot-Souletie, Nathalie [CHU Rangueil, Department of Cardiology, Toulouse (France)

2010-05-15

To compare cardiac MRI with right heart catheterisation in patients with pulmonary hypertension (PH) and to evaluate its ability to assess PH severity. Forty patients were included. MRI included cine and phase-contrast sequences, study of ventricular function, cardiac cavity areas and ratios, position of the interventricular septum (IVS) in systole and diastole, and flow measurements. We defined four groups according to the severity of PH and three groups according to IVS position: A, normal position; B, abnormal in diastole; C, abnormal in diastole and systole. IVS position was correlated with pulmonary artery pressures and PVR (pulmonary vascular resistance). Median pulmonary artery pressures and resistance were significantly higher in patients with an abnormal septal position compared with those with a normal position. Correlations were good between the right ventricular ejection fraction and PVR, right ventricular end-systolic volume and PAP, percentage of right ventricular area change and PVR, and diastolic and systolic ventricular area ratio and PVR. These parameters were significantly associated with PH severity. Cardiac MRI can help to assess the severity of PH. (orig.)

Effect of coronary artery recanalization on right ventricular function in patients with acute myocardial infarction

International Nuclear Information System (INIS)

Verani, M.S.; Tortoledo, F.E.; Batty, J.W.; Raizner, A.E.

1985-01-01

The effects of coronary artery recanalization by intracoronary administration of streptokinase on left ventricular function during acute myocardial infarction have received increasing attention in recent years. Although myocardial dysfunction is often more pronounced in the right ventricle than in the left ventricle in patients with acute inferior wall myocardial infarction, the effect of coronary artery recanalization on right ventricular dysfunction has not been previously addressed. Accordingly, in this investigation, 54 patients who participated in a prospective, controlled, randomized trial of recanalization during acute myocardial infarction were studied. Among 30 patients with inferior wall infarction, 19 had right ventricular dysfunction on admission; 11 of these 19 had positive uptake of technetium-99m pyrophosphate in the right ventricle, indicative of right ventricular infarction. Patients with successful recanalization exhibited improved right ventricular ejection fraction from admission to day 10. However, control patients and patients who did not undergo recanalization also exhibited improvement. These data indicate that the right ventricular dysfunction commonly associated with inferior wall infarction is often transient, and improvement is the rule, irrespective of early recanalization of the infarct vessel

Effects of metabolic syndrome on arterial function in different age groups: the Advanced Approach to Arterial Stiffness study.

Science.gov (United States)

Topouchian, Jirar; Labat, Carlos; Gautier, Sylvie; Bäck, Magnus; Achimastos, Apostolos; Blacher, Jacques; Cwynar, Marcin; de la Sierra, Alejandro; Pall, Denes; Fantin, Francesco; Farkas, Katalin; Garcia-Ortiz, Luis; Hakobyan, Zoya; Jankowski, Piotr; Jelakovic, Ana; Kobalava, Zhanna; Konradi, Alexandra; Kotovskaya, Yulia; Kotsani, Marina; Lazareva, Irina; Litvin, Alexander; Milyagin, Viktor; Mintale, Iveta; Persson, Oscar; Ramos, Rafael; Rogoza, Anatoly; Ryliskyte, Ligita; Scuteri, Angelo; Sirenko, Yuriy; Soulis, Georges; Tasic, Nebojsa; Udovychenko, Maryna; Urazalina, Saule; Wohlfahrt, Peter; Zelveian, Parounak; Benetos, Athanase; Asmar, Roland

2018-04-01

The aim of the Advanced Approach to Arterial Stiffness study was to compare arterial stiffness measured simultaneously with two different methods in different age groups of middle-aged and older adults with or without metabolic syndrome (MetS). The specific effects of the different MetS components on arterial stiffness were also studied. This prospective, multicentre, international study included 2224 patients aged 40 years and older, 1664 with and 560 without MetS. Patients were enrolled in 32 centres from 18 European countries affiliated to the International Society of Vascular Health & Aging. Arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI) and the carotid-femoral pulse wave velocity (CF-PWV) in four prespecified age groups: 40-49, 50-59, 60-74, 75-90 years. In this report, we present the baseline data of this study. Both CF-PWV and CAVI increased with age, with a higher correlation coefficient for CAVI (comparison of coefficients P Age-adjusted and sex-adjusted values of CF-PWV and CAVI were weakly intercorrelated (r = 0.06, P Age-adjusted and sex-adjusted values for CF-PWV but not CAVI were higher in presence of MetS (CF-PWV: 9.57 ± 0.06 vs. 8.65 ± 0.10, P age on CAVI and CF-PWV and suggests that age may have a more pronounced effect on CAVI, whereas MetS increases CF-PWV but not CAVI. This important finding may be due to heterogeneous effects of MetS components on CAVI. The clinical significance of these original results will be assessed during the longitudinal phase of the study.

Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 3. Posterior cerebral artery and circle of Willis

International Nuclear Information System (INIS)

Gloger, S.; Gloger, A.; Vogt, H.; Kretschmann, H.J.

1994-01-01

We present a three-dimensional anatomical computer model of the terminal branches of the posterior cerebral artery and circle of Willis, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries. This can help to identify the arteries in conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can be matched with CT, MR and PET images to indicate the areas of extension of the individual branches, allowing neuromorphological and functional correlations. (orig.)

Computer-assisted 3D reconstruction of the terminal branches of the cerebral arteries. Pt. 3. Posterior cerebral artery and circle of Willis

Energy Technology Data Exchange (ETDEWEB)

Gloger, S. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Gloger, A. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Vogt, H. (Dept. of Neuroanatomy, Hannover Medical School (Germany)); Kretschmann, H.J. (Dept. of Neuroanatomy, Hannover Medical School (Germany))

1994-05-01

We present a three-dimensional anatomical computer model of the terminal branches of the posterior cerebral artery and circle of Willis, acquired from equidistant serial anatomical slices of three brains. The reconstructions provide a clear picture from all angles of the complicated course of the terminal branches of the cerebral arteries. This can help to identify the arteries in conventional and magnetic resonance angiography. Our rendition of the cerebral arteries can be matched with CT, MR and PET images to indicate the areas of extension of the individual branches, allowing neuromorphological and functional correlations. (orig.)

Arterial Stiffness in Children: Pediatric Measurement and Considerations

Science.gov (United States)

Savant, Jonathan D.; Furth, Susan L.; Meyers, Kevin E.C.

2014-01-01

Background Arterial stiffness is a natural consequence of aging, accelerated in certain chronic conditions, and predictive of cardiovascular events in adults. Emerging research suggests the importance of arterial stiffness in pediatric populations. Methods There are different indices of arterial stiffness. The present manuscript focuses on carotid-femoral pulse wave velocity and pulse wave analysis, although other methodologies are discussed. Also reviewed are specific measurement considerations for pediatric populations and the literature describing arterial stiffness in children with certain chronic conditions (primary hypertension, obesity, diabetes, chronic kidney disease, hypercholesterolemia, genetic syndromes involving vasculopathy, and solid organ transplant recipients). Conclusions The measurement of arterial stiffness in children is feasible and, under controlled conditions, can give accurate information about the underlying state of the arteries. This potentially adds valuable information about the functionality of the cardiovascular system in children with a variety of chronic diseases well beyond that of the brachial artery blood pressure. PMID:26587447

Carotid artery stiffness, digital endothelial function, and coronary calcium in patients with essential thrombocytosis, free of overt atherosclerotic disease

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Vrtovec Matjaz

2017-05-01

Full Text Available Patients with myeloproliferative neoplasms (MPNs are at increased risk for atherothrombotic events. Our aim was to determine if patients with essential thrombocytosis (ET, a subtype of MPNs, free of symptomatic atherosclerosis, have greater carotid artery stiffness, worse endothelial function, greater coronary calcium and carotid plaque burden than control subjects.

A Multiscale Closed-Loop Cardiovascular Model, with Applications to Heart Pacing and Hemorrhage

Science.gov (United States)

Canuto, Daniel; Eldredge, Jeff; Chong, Kwitae; Benharash, Peyman; Dutson, Erik

2017-11-01

A computational tool is developed for simulating the dynamic response of the human cardiovascular system to various stressors and injuries. The tool couples zero-dimensional models of the heart, pulmonary vasculature, and peripheral vasculature to one-dimensional models of the major systemic arteries. To simulate autonomic response, this multiscale circulatory model is integrated with a feedback model of the baroreflex, allowing control of heart rate, cardiac contractility, and peripheral impedance. The performance of the tool is demonstrated in two scenarios: increasing heart rate by stimulating the sympathetic nervous system, and an acute 10 percent hemorrhage from the left femoral artery.

Autonomic Function Impairment and Brain Perfusion Deficit in Parkinson’s Disease

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Wei-Che Lin

2017-06-01

Full Text Available IntroductionAutonomic disorders have been recognized as important Parkinson’s disease (PD components. Some vulnerable structures are related to the central autonomic network and have also been linked to autonomic function alterations. The aims of the study are to evaluate the severity of the autonomic dysfunction and the cortical hypoperfusion using arterial spin labeling (ASL MRI. And then, possible relationships of significant between-group differences in perfusion pattern to clinical variables and autonomic functions were examined to determine the pharmaceutical effects of dopaminergic treatment on cerebral blood flow (CBF in patients with PD.MethodsBrain ASL MRI was carried out in 20 patients with PD (6 men and 14 women, mean age: 63.3 ± 6.4 years and 22 sex- and age-matched healthy volunteers to assess whole-brain CBF and the effects of dopaminergic therapy on perfusion. All subjects underwent a standardized evaluation of cardiovagal and adrenergic function including a deep breathing, Valsalva maneuver, and 5-min head-up tilt test. Perfusion MRI data were acquired on a 3.0 T scanner with a pulsed continuous ASL technique. The CBF, autonomic parameters, and clinical data were analyzed after adjusting for age and sex.ResultsPatients exhibited a decline in autonomic function (rapid heart rate in response to deep breathing, low baroreflex sensitivity, high systolic and diastolic pressure, and altered tilting test response, widespread low CBF, and robust response to dopaminergic therapy. Lower perfusion in the middle frontal gyrus was associated with increased clinical disease severity (Unified Parkinson’s Disease Rating Scale I score, P < 0.001. Lower perfusion in autonomic control areas, such as the frontal lobe and insula, were significantly associated with autonomic impairment (P < 0.001.ConclusionsOur study indicates that PD is a progressive neurodegenerative disorder that changes the perfusion of central nervous system

Functional Relevance of Coronary Artery Disease by Cardiac Magnetic Resonance and Cardiac Computed Tomography: Myocardial Perfusion and Fractional Flow Reserve

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Gianluca Pontone

2015-01-01

Full Text Available Coronary artery disease (CAD is one of the leading causes of morbidity and mortality and it is responsible for an increasing resource burden. The identification of patients at high risk for adverse events is crucial to select those who will receive the greatest benefit from revascularization. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography, but the diagnostic yield of elective invasive coronary angiography remains unfortunately low. Stress myocardial perfusion imaging by cardiac magnetic resonance (stress-CMR has emerged as an accurate technique for diagnosis and prognostic stratification of the patients with known or suspected CAD thanks to high spatial and temporal resolution, absence of ionizing radiation, and the multiparametric value including the assessment of cardiac anatomy, function, and viability. On the other side, cardiac computed tomography (CCT has emerged as unique technique providing coronary arteries anatomy and more recently, due to the introduction of stress-CCT and noninvasive fractional flow reserve (FFR-CT, functional relevance of CAD in a single shot scan. The current review evaluates the technical aspects and clinical experience of stress-CMR and CCT in the evaluation of functional relevance of CAD discussing the strength and weakness of each approach.

Improvement of exercise ventricular function in patients of coronary artery bypass surgery

International Nuclear Information System (INIS)

Kawasuji, Michio; Sawa, Shigeharu; Tedoriya, Takeo; Iwa, Takashi; Taki, Jun-ichi; Bunkou, Hisashi

1989-01-01

Thirty-five patients underwent exercise blood pool scintigraphy before and 4 weeks after coronary artery bypass graft (CABG). Left ventricular ejection fraction (EF), peak ejection rate (PER), peak filling rate (PFR), and one third peak filling rate (1/3 FR) were calculated. Exercise-induced EF was significantly higher after than before CABG (+2.4±6.1% vs -3.9±7.3%). Irrespective of exercise, preoperative PER was unchanged. Postoperative exercise significantly increased PER from 2.88±0.71 sec -1 to 3.85±0.85 sec -1 (p<0.01). Exercise also significantly increased PFR after GABG when compared with that before GABF. 1/3FR did not differ before and after CABG. Exercise blood pool scintigraphy was useful in evaluating ventricular function before and after CABG. (Namekawa, K)

Whole-body vibration as a potential countermeasure for dynapenia and arterial stiffness

Directory of Open Access Journals (Sweden)

Arturo Figueroa

2016-09-01

Full Text Available Age-related decreases in muscle mass and strength are associated with decreased mobility, quality of life, and increased cardiovascular risk. Coupled with the prevalence of obesity, the risk of death becomes substantially greater. Resistance training (RT has a well-documented beneficial impact on muscle mass and strength in young and older adults, although the high-intensity needed to elicit these adaptations may have a detrimental or negligible impact on vascular function, specifically on arterial stiffness. Increased arterial stiffness is associated with systolic hypertension, left ventricular hypertrophy, and myocardial ischemia. Therefore, improvements of muscle strength and arterial function are important in older adults. Recently, whole-body vibration (WBV exercise, a novel modality of strength training, has shown to exhibit similar results on muscle strength as RT in a wide-variety of populations, with the greatest impact in elderly individuals with limited muscle function. Additionally, WBV training has been shown to have beneficial effects on vascular function by reducing arterial stiffness. This article reviews relevant publications reporting the effects of WBV on muscle strength and/or arterial stiffness. Findings from current studies suggest the use of WBV training as an alternative modality to traditional RT to countermeasure the age-related detriments in muscle strength and arterial stiffness in older adults.

Whole-body vibration as a potential countermeasure for dynapenia and arterial stiffness.

Science.gov (United States)

Figueroa, Arturo; Jaime, Salvador J; Alvarez-Alvarado, Stacey

2016-09-01

Age-related decreases in muscle mass and strength are associated with decreased mobility, quality of life, and increased cardiovascular risk. Coupled with the prevalence of obesity, the risk of death becomes substantially greater. Resistance training (RT) has a well-documented beneficial impact on muscle mass and strength in young and older adults, although the high-intensity needed to elicit these adaptations may have a detrimental or negligible impact on vascular function, specifically on arterial stiffness. Increased arterial stiffness is associated with systolic hypertension, left ventricular hypertrophy, and myocardial ischemia. Therefore, improvements of muscle strength and arterial function are important in older adults. Recently, whole-body vibration (WBV) exercise, a novel modality of strength training, has shown to exhibit similar results on muscle strength as RT in a wide-variety of populations, with the greatest impact in elderly individuals with limited muscle function. Additionally, WBV training has been shown to have beneficial effects on vascular function by reducing arterial stiffness. This article reviews relevant publications reporting the effects of WBV on muscle strength and/or arterial stiffness. Findings from current studies suggest the use of WBV training as an alternative modality to traditional RT to countermeasure the age-related detriments in muscle strength and arterial stiffness in older adults.

Characteristics of Carotid Artery Structure and Mechanical Function and Their Relationships with Aortopathy in Patients with Bicuspid Aortic Valves

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Mihyun Kim

2017-08-01

Full Text Available Patients with a bicuspid aortic valve (BAV often have proximal aortic dilatation and systemic vascular dysfunction. We hypothesized that BAV patients would have different carotid artery structural and functional characteristics compared to tricuspid aortic valve (TAV patients. In 28 patients with surgically confirmed BAV and 27 patients with TAV, intima media thickness (IMT, number of plaques, fractional area change (FAC, global circumferential strain (GCS, and standard deviation of CS (SD-CS in both common carotid arteries were assessed using duplex ultrasound and velocity vector imaging (VVI. Patients with BAV were younger and had less co-morbidity, but showed a significantly larger ascending aorta (43.3 ± 7.5 vs. 37.0 ± 6.2 mm, p < 0.001 and a higher prevalence of aortopathy (61 vs. 30%, p = 0.021 than those with TAV. BAV patients showed a significantly lower IMT and fewer plaques. Although FAC and GCS were not significantly different between the two groups, they tended to be lower in the BAV group when each group was divided into three subgroups according to age. There was a significant age-dependent increase in IMT and decreases in FAC and GCS in the TAV group (p = 0.005, p = 0.001, p = 0.002, respectively, but this phenomenon was not evident in the BAV group (p = 0.074, p = 0.248, p = 0.394, respectively. BAV patients with aortopathy showed a higher SD-CS than those without aortopathy (p = 0.040, reflecting disordered mechanical function. In conclusion, BAV patients have different carotid artery structure and function compared with TAV patients, suggesting intrinsic vascular abnormalities that are less affected by established cardiovascular risk factors and more strongly related to the presence of aortopathy.

Bypass grafting to the anterior tibial artery.

Science.gov (United States)

Armour, R H

1976-01-01

Four patients with severe ischaemia of a leg due to atherosclerotic occlusion of the tibial and peroneal arteries had reversed long saphenous vein grafts to the patent lower part of the anterior tibial artery. Two of these grafts continue to function 19 and 24 months after operation respectively. One graft failed on the fifth postoperative day and another occluded 4 months after operation. The literature on femorotibial grafting has been reviewed. The early failure rate of distal grafting is higher than in the case of femoropopliteal bypass, but a number of otherwise doomed limbs can be salvaged. Contrary to widely held views, grafting to the anterior tibial artery appears to give results comparable to those obtained when the lower anastomosis is made to the posterior tibial artery.

Impact of acute caffeine ingestion on endothelial function in subjects with and without coronary artery disease.

Science.gov (United States)

Shechter, Michael; Shalmon, Guy; Scheinowitz, Mickey; Koren-Morag, Nira; Feinberg, Micha S; Harats, Dror; Sela, Ben Ami; Sharabi, Yehonatan; Chouraqui, Pierre

2011-05-01

Although coffee is a widely used, pharmacologically active beverage, its impact on the cardiovascular system is controversial. To explore the effect of acute caffeine ingestion on brachial artery flow-mediated dilation (FMD) in subjects without coronary artery disease (CAD; controls) and patients with CAD, we prospectively assessed brachial artery FMD in 40 controls and 40 age- and gender-matched patients with documented stable CAD on 2 separate mornings 1 week to 2 weeks apart. After overnight fasting, discontinuation of all medications for ≥12 hours, and absence of caffeine for >48 hours, participants received capsules with caffeine 200 mg or placebo. One hour after drug ingestion, participants underwent brachial artery FMD and nitroglycerin-mediated dilation (NTG) using high-resolution ultrasound. As expected, patients with CAD were more often diabetic, hypertensive, obese, dyslipidemic, and smoked more than controls (p <0.01 for all comparisons). Aspirin, Clopidogrel, angiotensin-converting enzyme inhibitors, β blockers, and statins were significantly more common in patients with CAD than in controls (p <0.01 for all comparisons). At baseline, FMD, but not NTG, was significantly lower in patients with CAD compared to controls. Acute caffeine ingestion significantly increased FMD (patients with CAD 5.6 ± 5.0% vs 14.6 ± 5.0%, controls 8.4 ± 2.9% vs 18.6 ± 6.8%, p <0.001 for all comparisons) but not NTG (patients with CAD 13.0 ± 5.2% vs 13.8 ± 6.1%, controls 12.9 ± 3.9% vs 13.9 ± 5.8%, p = NS for all comparisons) and significantly decreased high-sensitivity C-reactive protein (patients with CAD 2.6 ± 1.4 vs 1.4 ± 1.2 mg/L, controls 3.4 ± 3.0 vs 1.2 ± 1.0 mg/L, p <0.001 for all comparisons) in the 2 groups compared to placebo. In conclusion, acute caffeine ingestion significantly improved endothelial function assessed by brachial artery FMD in subjects with and without CAD and was associated with lower plasma markers of inflammation. Copyright �

ARTERIAL REVASCULARIZATION WITH THE RIGHT GASTROEPIPLOIC ARTERY AND INTERNAL MAMMARY ARTERIES IN 300 PATIENTS

NARCIS (Netherlands)

GRANDJEAN, JG; BOONSTRA, PW; DENHEYER, P; EBELS, T; KIRKLIN, JW

From September 1989 to September 1992, the right gastroepiploic artery in combination with one or both internal mammary arteries was used as a graft in 300 patients who underwent coronary artery bypass grafting. The gastroepiploic artery was the primary choice in preference to the saphenous vein.

Fibulin-4 is essential for maintaining arterial wall integrity in conduit but not muscular arteries.

Science.gov (United States)

Halabi, Carmen M; Broekelmann, Thomas J; Lin, Michelle; Lee, Vivian S; Chu, Mon-Li; Mecham, Robert P

2017-05-01

Homozygous or compound heterozygous mutations in fibulin-4 ( FBLN4 ) lead to autosomal recessive cutis laxa type 1B (ARCL1B), a multisystem disorder characterized by significant cardiovascular abnormalities, including abnormal elastin assembly, arterial tortuosity, and aortic aneurysms. We sought to determine the consequences of a human disease-causing mutation in FBLN4 (E57K) on the cardiovascular system and vascular elastic fibers in a mouse model of ARCL1B. Fbln4 E57K/E57K mice were hypertensive and developed arterial elongation, tortuosity, and ascending aortic aneurysms. Smooth muscle cell organization within the arterial wall of large conducting vessels was abnormal, and elastic fibers were fragmented and had a moth-eaten appearance. In contrast, vessel wall structure and elastic fiber integrity were normal in resistance/muscular arteries (renal, mesenteric, and saphenous). Elastin cross-linking and total elastin content were unchanged in large or small arteries, whereas elastic fiber architecture was abnormal in large vessels. While the E57K mutation did not affect Fbln4 mRNA levels, FBLN4 protein was lower in the ascending aorta of mutant animals compared to wild-type arteries but equivalent in mesenteric arteries. We found a differential role of FBLN4 in elastic fiber assembly, where it functions mainly in large conduit arteries. These results suggest that elastin assembly has different requirements depending on vessel type. Normal levels of elastin cross-links in mutant tissue call into question FBLN4's suggested role in mediating lysyl oxidase-elastin interactions. Future studies investigating tissue-specific elastic fiber assembly may lead to novel therapeutic interventions for ARCL1B and other disorders of elastic fiber assembly.

Long-term excess fat and/or fructose ingestion causes changes in small artery K+ transporter expression and function with effects on blood pressure

DEFF Research Database (Denmark)

Olsen, A. K.; Salomonsson, M.; Sørensen, C. M.

+ channels, Na/K-ATPase, and voltage-gated Ca2+ channels are crucial determinants of resistance artery tone. Only scarce information is available on the role of K+ transporters in pathophysiological mechanisms induced by long-term feeding of laboratory rats with either high-fat, high-fructose or high-fat/high-fructose...... diet. HYPOTHESIS: A 28-week diet consisting of high-fat or high-fructose, or both, will lead to changes in K+ transporter expression and function, which will be linked with changes in blood pressure, arterial smooth muscle function, endothelial function and passive structural/mechanical properties....... METHODS: Male Sprague Dawley rats (4 weeks) were randomized into 4 diet groups receiving a diet with normal chow (CTR, N=19), high-fat chow (60% saturated fat, FAT, N=18), high-fructose (10% in drinking water; FRUC, N=15), or a combination of fat/fructose (FAT/FRUC, N=15) for 28 weeks. Systolic blood...

Interventional treatment of emergent hepatic artery thrombosis after liver transplantation

International Nuclear Information System (INIS)

Liu Fengyong; Wang Maoqiang; Wang Zhijun; Wang Zhongpu; Shi Xianjie; Zhou Ningxin

2006-01-01

Objective: To evaluate the safety and efficacy of the endovascular interventional techniques for the management of emergent hepatic artery thrombosis (HAT) after orthotopic liver transplantation (OLT). Methods: Ten patients (8 men and 2 women with mean age of 47 years) diagnosed with HAT after OLT were treated with interventional procedures. All patients presented with elevation of liver enzymes and bilirubin levels. The diagnosis of the HAT was suggested by doppler ultrasonography and confirmed by angiography at 16 hours to 10 days (mean, 4.5 days) after OLT. Interventional techniques consisted of indwelling transcatheter hepatic arterial thrombolysis with a low dose of urokinase monitored under ultrasonography every 6-12 hours and stent placement in the stenotic segment of the hepatic artery was undertaken. Systemic intravenous low dose of heparin was given contemporaneously. Results: Complete occlusion of the proper HA was achieved in 10 patients. Hepatic arterial flow was re-established in 8 of the 10 patients (80%) at 12 hours to 9 days (mean, 4.8 days) after the intra-arterial thrombolysis, with significant improvement of liver function. Hepatic artery stenosis at the anastomosis was found in the 8 patients, and a stent placement in the stenotic segment was performed successfully in 7 patients with degree of stenosis over 90%.Intra-arterial thrombolysis was failed in 2 cases. Intraperitoneal hemorrhage from the anastomosis occurred in 1 patient at 12 hours after the treatment, and was emergently taken for the graft revision with reanastomosis. One patient with complete occlusion of the hepatic artery at 7 days after the treatment, but having collateral flow of the liver for maintaining liver function and thus sparing further intervention. 8 patients with successful hepatic arterial recanalization carried along a good clinical course with normal graft function at a median 12 months (range, 4 to 20 months), and patent hepatic arterial flow was identified by

[Anatomy character of renal artery and treatment of living-donor renal transplantation].

Science.gov (United States)

Zhang, Lei; Fei, Ji-guang; Chen, Li-zhong; Wang, Chang-xi; Deng, Su-xiong; Qiu, Jiang; Li, Jun; Chen, Guo-dong; Huang, Gang

2009-12-15

To study the anatomy characters of renal artery and the treatment of multiple arteries in living donor renal grafts. Records of 142 living donors were analyzed in our center. We analyzed the anatomic structure of renal arteries by DSA and CTA pre-transplantation. Thirty-one kidneys with multiple arteries were transplanted after reconstruction. Then clinical effects were compared between multiple-renal-arteries group (n=31) and single-renal-artery group (n=111). The incidence of multiple renal artery was 30.99%, and there was no difference between both sides (left kidney 22.54%, right kidney 22.13%). If the multiple artery occurred in left or right kidney, the incidence of the multiple artery occurred in the other side was 56.25% and 60.00%, respectively. The diameter of left main renal artery was more magnanimous (P=0.001) and the first branch was more closed to abdominal aorta (P=0.004). Operation time and warm/cool ischemia time were longer in the multiple-renal-arteries group. However, estimated blood loss, delayed graft function, acute rejection and flow rate of arcuate artery were similar in both groups, the same as serum creatinine and serum creatinine clearance rate on day 7, 1 month and 3 month post-operation. It was shown by repeated measures ANOVA that graft with multiple arteries didn't affect the tendency of renal function at early time post-operation. Comprehending the character of renal artery and accurate treatment of multiple artery anastomosis are critical for the effect of the living kidney transplantation.

Exercise promotes collateral artery growth mediated by monocytic nitric oxide.

Science.gov (United States)

Schirmer, Stephan H; Millenaar, Dominic N; Werner, Christian; Schuh, Lisa; Degen, Achim; Bettink, Stephanie I; Lipp, Peter; van Rooijen, Nico; Meyer, Tim; Böhm, Michael; Laufs, Ulrich

2015-08-01

Collateral artery growth (arteriogenesis) is an important adaptive response to hampered arterial perfusion. It is unknown whether preventive physical exercise before limb ischemia can improve arteriogenesis and modulate mononuclear cell function. This study aimed at investigating the effects of endurance exercise before arterial occlusion on MNC function and collateral artery growth. After 3 weeks of voluntary treadmill exercise, ligation of the right femoral artery was performed in mice. Hindlimb perfusion immediately after surgery did not differ from sedentary mice. However, previous exercise improved perfusion restoration ≤7 days after femoral artery ligation, also when exercise was stopped at ligation. This was accompanied by an accumulation of peri-collateral macrophages and increased expression of endothelial nitric oxide synthase and inducible nitric oxide synthase (iNOS) in hindlimb collateral and in MNC of blood and spleen. Systemic monocyte and macrophage depletion by liposomal clodronate but not splenectomy attenuated exercise-induced perfusion restoration, collateral artery growth, peri-collateral macrophage accumulation, and upregulation of iNOS. iNOS-deficient mice did not show exercise-induced perfusion restoration. Transplantation of bone marrow-derived MNC from iNOS-deficient mice into wild-type animals inhibited exercise-induced collateral artery growth. In contrast to sedentary controls, thrice weekly aerobic exercise training for 6 months in humans increased peripheral blood MNC iNOS expression. Circulating mononuclear cell-derived inducible nitric oxide is an important mediator of exercise-induced collateral artery growth. © 2015 American Heart Association, Inc.

Occipital Artery Function during the Development of 2-Kidney, 1-Clip Hypertension in Rats

OpenAIRE

Stephen P. Chelko; Chad W. Schmiedt; Tristan H. Lewis; Tom P. Robertson; Stephen J. Lewis

2014-01-01

This study compared the contractile responses elicited by angiotensin II (AII), arginine vasopressin (AVP), and 5-hydroxytryptamine (5-HT) in isolated occipital arteries (OAs) from sham-operated (SHAM) and 2-kidney, 1-clip (2K-1C) hypertensive rats. OAs were isolated and bisected into proximal segments (closer to the common carotid artery) and distal segments (closer to the nodose ganglion) and mounted separately on myographs. On day 9, 2K-1C rats had higher mean arterial blood pressures, hea...

Outcomes of anatomical versus functional testing for coronary artery disease.

Science.gov (United States)

Douglas, Pamela S; Hoffmann, Udo; Patel, Manesh R; Mark, Daniel B; Al-Khalidi, Hussein R; Cavanaugh, Brendan; Cole, Jason; Dolor, Rowena J; Fordyce, Christopher B; Huang, Megan; Khan, Muhammad Akram; Kosinski, Andrzej S; Krucoff, Mitchell W; Malhotra, Vinay; Picard, Michael H; Udelson, James E; Velazquez, Eric J; Yow, Eric; Cooper, Lawton S; Lee, Kerry L

2015-04-02

Many patients have symptoms suggestive of coronary artery disease (CAD) and are often evaluated with the use of diagnostic testing, although there are limited data from randomized trials to guide care. We randomly assigned 10,003 symptomatic patients to a strategy of initial anatomical testing with the use of coronary computed tomographic angiography (CTA) or to functional testing (exercise electrocardiography, nuclear stress testing, or stress echocardiography). The composite primary end point was death, myocardial infarction, hospitalization for unstable angina, or major procedural complication. Secondary end points included invasive cardiac catheterization that did not show obstructive CAD and radiation exposure. The mean age of the patients was 60.8±8.3 years, 52.7% were women, and 87.7% had chest pain or dyspnea on exertion. The mean pretest likelihood of obstructive CAD was 53.3±21.4%. Over a median follow-up period of 25 months, a primary end-point event occurred in 164 of 4996 patients in the CTA group (3.3%) and in 151 of 5007 (3.0%) in the functional-testing group (adjusted hazard ratio, 1.04; 95% confidence interval, 0.83 to 1.29; P=0.75). CTA was associated with fewer catheterizations showing no obstructive CAD than was functional testing (3.4% vs. 4.3%, P=0.02), although more patients in the CTA group underwent catheterization within 90 days after randomization (12.2% vs. 8.1%). The median cumulative radiation exposure per patient was lower in the CTA group than in the functional-testing group (10.0 mSv vs. 11.3 mSv), but 32.6% of the patients in the functional-testing group had no exposure, so the overall exposure was higher in the CTA group (mean, 12.0 mSv vs. 10.1 mSv; P<0.001). In symptomatic patients with suspected CAD who required noninvasive testing, a strategy of initial CTA, as compared with functional testing, did not improve clinical outcomes over a median follow-up of 2 years. (Funded by the National Heart, Lung, and Blood Institute

Regional blood flow analysis and its relationship with arterial branch lengths and lumen volume in the coronary arterial tree

International Nuclear Information System (INIS)

Molloi, Sabee; Wong, Jerry T

2007-01-01

The limitations of visually assessing coronary artery disease are well known. These limitations are particularly important in intermediate coronary lesions (30-70% diameter stenosis) where it is difficult to determine whether a particular lesion is the cause of ischaemia. Therefore, a functional measure of stenosis severity is needed. The purpose of this study is to determine whether the expected maximum coronary blood flow in an arterial tree is predictable from its sum of arterial branch lengths or lumen volume. Using a computer model of a porcine coronary artery tree, an analysis of blood flow distribution was conducted through a network of millions of vessels that included the entire coronary artery tree down to the first capillary branch. The flow simulation results show that there is a linear relationship between coronary blood flow and the sum of its arterial branch lengths. This relationship holds over the entire arterial tree. The flow simulation results also indicate that there is a 3/4 er relation between coronary blood flow (Q) and the sum of its arterial lumen volume (V). Moreover, there is a linear relationship between normalized Q and normalized V raised to a power of 3/4 over the entire arterial tree. These results indicate that measured arterial branch lengths or lumen volumes can be used to predict the expected maximum blood flow in an arterial tree. This theoretical maximum blood flow, in conjunction with an angiographically measured blood flow, can potentially be used to calculate fractional flow reserve based entirely on angiographic data

Pulmonary arterial hypertension secondary to chronic thromboemboli

International Nuclear Information System (INIS)

Crysikopoulos, H.; Forrest, J.V.; Olson, L.K.; Roberts, A.C.

1989-01-01

The authors report their experience in 150 patients with pulmonary arterial hypertension secondary to chronic pulmonary embolism (CPE). Plain film findings are variable, commonly nonspecific. Occasionally nonuniformity of pulmonary perfusion or truncation of central pulmonary arteries suggest CPE. Multiple, large, unmatched perfusion defects are the most common scintigraphic observations. CT can exclude conditions mimicking CPE, particularly fibrosing mediastinitis. Pulmonary arteriography depicts the location and distribution of emboli. CPE is becoming an increasingly important entity to recognize because of available surgical treatment. Thromboendarterectomy may improve functional status and survival. The diagnosis should be considered in any patient with pulmonary arterial hypertension

[Ultrasonographic evaluation of selected parameters of the endothelial function in brachial arteries and IMT measurements in carotid arteries in children with diabetes type 1 using personal insulin pumps--preliminary report].

Science.gov (United States)

Tołwińska, Joanna; Głowińska-Olszewska, Barbara; Urban, Mirosława; Florys, Bozena; Peczyńska, Jadwiga

2006-01-01

endothelial function in type 1 diabetic children and seems to be a significant tool in delaying the atherosclerotic process. 2. We need more examinations to explain the role of treatment intensification in common carotid arteries wall morphology in type 1 diabetic children. 3. The ultrasonographic detection of atherosclerotic changes in arterial vessels can help in the evaluation of the changes due to different methods of diabetes treatment.

Close to Transplant Renal Artery Stenosis and Percutaneous Transluminal Treatment

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Leonardou Polytimi

2011-01-01

Full Text Available Purpose. To evaluate the efficacy of percutaneous transluminal angioplasty (PTA in the management of arterial stenosis located close to the allograft anastomosis (close-TRAS. Materials and Methods. 31 patients with renal transplants were admitted to our institution because of persistent hypertension and impairment of transplant renal function and underwent angiography for vascular investigation. 27 were diagnosed suffering from transplant renal artery stenosis (TRAS, whereas 4 had severe iliac artery stenosis proximal to the transplant anastomosis (Prox-TRAS. 3 cases of TRAS coexisted with segmental renal arterial stenosis, whereas 3 other cases of TRAS were caused by kinking and focal stenosis in the middle of the transplanted renal artery. Results. Angioplasty and stenting were successfully applied to all patients with iliac artery stenosis as well as to those with TRAS and segmental artery stenosis. Two of three patients with kinking were well treated with angioplasty and stenting, whereas one treated only with angioplasty necessitated surgery. No major procedure-related complications appeared, and the result was decrease of the serum creatinine level and of the blood pressure. Conclusions. PTA is the appropriate initial treatment of TRAS and close-TRAS, with low morbidity and mortality rates, achieving improvement of graft function and amelioration of hypertension.

The internal carotid artery stenosis or occlusion. The evaluation for the posterior communicating artery on DSA and MRA

International Nuclear Information System (INIS)

Zhao Yunhui; Gao Xinjiang; Ma Zhubin; Xu Yikai

2003-01-01

Objective: To study the changes of the posterior communicating artery in patients with internal carotid artery (ICA) severe stenosis or occlusion on digital subtract angiography (DSA) and magnetic resonance angiography (MRA). Methods: DSA or MRA findings were analyzed in 74 patients with ICA stenosis or occlusion and in 120 persons selected in the control group, who were unremarkable on cerebral DSA or MRA. Results: On DSA, the presence rate of ipsilateral posterior communicating artery (PCoA) between the study group and the control group had no significant difference; on MRA the rate in the study group was significantly higher than the control group (P 0.05). In the study group, the presence rate of PCoA on DSA was significantly higher than that on MRA (P 0.05). The presence rate of PCoA shown no significant difference between the cases with unilateral ICA involved and cases with bilateral ICA involved. Conclusion: The posterior communicating artery is very important to the patients with the internal carotid artery stenosis or occlusion. Its dilatation on DSA and MRA or appearance on MRA shows its compensation. DSA is valuable in the evaluation of the posterior communicating artery. MRA is a noninvasive and functional imaging method for evaluation the posterior communicating artery

Evaluation of Cardiac and Valvular Function after Arterial Switch Operation: A Midterm Follow-Up

Directory of Open Access Journals (Sweden)

Hamid Amoozgar

2013-09-01

Full Text Available Objectives: Transposition of Great Arteries (TGA is a serious congenital heart disease and anatomic correction in the first few weeks of life has revealed good outcomes nowadays. In this study, we aimed to evaluate the myocardial and valvular function at midterm postoperative follow-up. Patients and Methods: In this study, thirty-three patients with TGA and Arterial Switch Operation (ASO were evaluated by 2-dimensional, M-mode, Doppler, and pulsed Tissue Doppler. These patients were compared with 33 healthy children of the same age and gender as the normal control group. Student’s t-test and Pearson correlation were used to analyze the data. Besides, P<0.05 was considered as statistically significant. Results: The mean follow up time was 40.9±5.6 months. Among the 33 patients with ASO, 6% had mild pulmonary stenosis, while 3% had mild pulmonary insufficiency. Aortic stenosis and aortic insufficiency of trivial to mild degree was seen in 12% and 12% of the patients, respectively. The patients’ systolic velocity of tricuspid (S, early diastolic velocity of tricuspid (Ea, and late velocity of tricuspid valve (Aa were significantly different from those of the controls (P<0.001. Also, pulmonary annulus diameter was significantly dilated in the patients compared to the controls (1.67±0.41 vs. 1.29±0.28, P≤0.001. Besides, aortic annulus diameter (1.56±0.42 vs. 1.24±0.21, P=0.001 and also aortic sinus diameter (2.06±0.41 vs. 1.44±0.34, P=0.002 were significantly dilated, while sinutuboar junction diameter (1.65±0.5 vs. 1.28±0.29, P=0.094 was not dilated. Left ventricular function was in the normal range. Conclusions: This study showed good left ventricular function, but some abnormalities in lateral tricuspid tissue Doppler velocities. Neoaortic and pulmonary diameters were significantly dilated, while aortic and pulmonary insufficiencies were clinically insignificant in most of the patients. Long-term follow-up is necessary in these

Does training-induced orthostatic hypotension result from reduced carotid baroreflex responsiveness?

Science.gov (United States)

Pawelczyk, James A.; Raven, Peter B.

1994-01-01

As manned space travel has steadily increased in duration and sophistication, the answer to a simple, relevant question remains elusive. Does endurance exercise training - high intensity rhythmic activity, performed regularly for extended periods of time - alter the disposition to, or severity of, postflight orthostatic hypotension? Research results continue to provide different views; however, data are difficult to compare because of the following factors that vary between investigations: the type of orthostatic stress imposed (+Gz, lower body negative pressure (LBNP), head-up tilt); pretest perturbations used (exercise, heat exposure, head-down tilting, bed rest, water immersion, hypohydration, pharmacologically-induced diuresis); the length of the training program used in longitudinal investigations (days versus weeks versus months); the criteria used to define fitness; and the criteria used to define orthostatic tolerance. Generally, research results indicate that individuals engaged in aerobic exercise activities for a period of years have been reported to have reduced orthostatic tolerance compared to untrained control subjects, while the results of shorter term longitudinal studies remain equivocal. Such conclusions suggest that chronic athletic training programs reduce orthostatic tolerance, whereas relatively brief (days to weeks) training programs do not affect orthostatic tolerance to any significant degree (increase or decrease). A primary objective was established to identify the alterations in blood pressure control that contribute to training-induced orthostatic hypotension (TIOH). Although any aspect of blood pressure regulation is suspect, current research has been focused on the baroreceptor system. Reductions in carotid baroreflex responsiveness have been documented in exercise-trained rabbits, reportedly due to an inhibitory influence from cardiac afferent, presumably vagal, nerve fibers that is abolished with intrapericardiac denervation. The

Valutazione morfo-funzionale in pazienti ipertesi con stenosi dell'arteria renale; Correlazioni tra angiografia e scintigrafia dinamica. Morpho-functional evaluation in hypertensive patients with renal artery stenosis; Correlations between angiography and radionuclide renography

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Cuocolo, A; Celentano, L; Nappi, A [Naples Univ. (Italy). Ist. di Scienze Radiologiche; Neumann, R D; Salvatore, M [Naples Univ. (Italy). Cattedra di Medicina Nucleare

1991-01-01

Renovascula hypertension is the most important and common cause of secondary hypertension. We studied 10 patients with arterial hypertension and different degrees of renal artery stenosis to assess the usefulness of dynamic radionuclide renography in evaluating renal perfusion and funcion, and to compare funcional radionuclide results to the morphological findings of renal angiography. Computer-assisted dynamic renal with {sup 00m}Tc diethylenetriaminepentaacetic acid (DTPA) and {sup 131}I orthoiodohippurate (OIH), and renal artheriography were also employed in all patients. In all patients, radionuclide results matched angiography findings in quality. In particular, 3 patients with hemodynamical insignificant renal artery stenosis exhibited normal perfusion and function at dynamic radionuclide renography. Seven patients had significant renal artery stenosis and associated functional changes at dynamic radionuclide renography. Quantitative comparison of all patients showed a significant correlation (r=0.866, p<0.001) between the degree of renal artery stenosis, quantified as the percentage of narrowing as compared to adjacent/contralateral normal vessel diameter, and the results of split renal function, as assessed during OIH studies and expressed per kidney as a percentage of the net total counts of both kidneys. In conclusion, our results demonstrated dynamic radionuclide renography to be a valuable secondary to renal artery stenosis in hypertensive patients, providing complementary results to arteriography.

Comparably improved health-related quality of life after total arterial revascularization versus conventional coronary surgery--Copenhagen arterial revascularization randomized patency and outcome trial

DEFF Research Database (Denmark)

Damgaard, Sune; Lund, Jens T; Lilleør, Nikolaj B

2011-01-01

OBJECTIVE: We compared health-related quality of life up to 11 months after coronary artery bypass grafting using total arterial revascularization versus conventional coronary surgery. METHODS: In this randomized single-center trial, 161 patients underwent total arterial revascularization using.......01). For total arterial revascularization, there were also not statistically significant improvements for 'physical component summary' (P=0.09), 'bodily pain' (P=0.07) and 'vitality' (P=0.08). CONCLUSION: Health-related quality of life up to 1 year after total arterial revascularization is equal or slightly...... of the general Danish population. On all scales of the SF-36, there was statistically significant improvement at 3 and 11 months in both groups. For 'social functioning', the improvement following total arterial revascularization was significantly higher than following conventional revascularization (P=0...

Relations of Digital Vascular Function, Cardiovascular Risk Factors, and Arterial Stiffness: The Brazilian Longitudinal Study of Adult Health (ELSA‐Brasil) Cohort Study

Science.gov (United States)

Brant, Luisa C. C.; Hamburg, Naomi M.; Barreto, Sandhi M.; Benjamin, Emelia J.; Ribeiro, Antonio L. P.

2014-01-01

Background Vascular dysfunction is an early expression of atherosclerosis and predicts cardiovascular (CV) events. Peripheral arterial tonometry (PAT) evaluates basal pulse amplitude (BPA), endothelial function (PAT ratio), and wave reflection (PAT‐AIx) in the digital microvessels. In Brazilian adults, we investigated the correlations of PAT responses to CV risk factors and to carotid‐femoral pulse wave velocity (PWV), a measure of arterial stiffness. Methods and Results In a cross‐sectional study, 1535 participants of the ELSA‐Brasil cohort underwent PAT testing (52±9 years; 44% women). In multivariable analyses, more‐impaired BPA and PAT ratios were associated with male sex, higher body mass index (BMI), and total cholesterol/high‐density lipoprotein. Higher age and triglycerides were related to higher BPA, whereas lower systolic blood pressure, hypertension (HTN) treatment, and prevalent CV disease (CVD) were associated with lower PAT ratio. PAT‐AIx correlated positively with female sex, advancing age, systolic and diastolic blood pressures, and smoking and inversely to heart rate, height, BMI, and prevalent CVD. Black race was associated with lower BPA, higher PAT ratio, and PAT‐AIx. Microvessel vasodilator function was not associated with PWV. Higher PAT‐AIx was modestly correlated to higher PWV and PAT ratio and inversely correlated to BPA. Conclusion Metabolic risk factors are related to impaired microvessel vasodilator function in Brazil. However, in contrast to studies from the United States, black race was not associated with an impaired microvessel vasodilator response, implying that vascular function may vary by race across populations. PAT‐AIx relates to HTN, may be a valid measure of wave reflection, and provides distinct information from arterial stiffness. PMID:25510401

Quantitative evaluation of the structure and function of the common carotid artery in hypertriglyceridemic subjects using ultrasound radiofrequency-data technology

International Nuclear Information System (INIS)

Dan, Hai-Jun; Wang, Yan; Sha, Hai-Jing; Wen, Shu-Bin

2012-01-01

Assessment of the properties of blood-vessel walls by ultrasound radiofrequency (RF)-data technology is an innovative technique. We quantitatively evaluated the intima-media thickness (IMT) and arterial elasticity of the common carotid artery (CCA) in asymptomatic subjects with hypertriglyceridemia (HTG) using RF-data technology. Thirty HTG subjects and 30 matched controls were enrolled in the study. The common carotid arterial systolic diameter, diastolic diameter, IMT, carotid distensibility (CD), local pulse wave velocity (PWVβ), and stiffness (β) were compared between the two groups, as was the correlation between triglyceride level and the parameters mentioned above. The HTG group had significantly higher values of CCA-IMT compared with the control group (p 0.05). The level of triglycerides had significant positive correlations with CCA-IMT (r = 0.493, p < 0.001), whereas significant correlations with CD, PWVβ, and β were not observed in the HTG group. Ultrasound RF-data technology can be used to non-invasively and quantitatively detect the change in the structure and function of the CCA in asymptomatic HTG subjects for evaluating preclinical atherosclerosis.

The adventitia layer modulates the arterial wall elastic response to intra-aortic counterpulsation: in vivo studies.

Science.gov (United States)

Cabrera-Fischer, Edmundo I; Bia, Daniel; Zócalo, Yanina; Wray, Sandra; Armentano, Ricardo

2013-12-01

There is a relationship between the intra-aortic balloon pumping (IABP) benefits and the dynamic behavior of muscular arteries, which is associated with induced changes on the vessel walls through an endothelial-dependent mechanism. The arterial wall elastic behavior is influenced by adventitial function; however, no studies were performed in order to elucidate if this layer plays a role in the changes determined by IABP. Our aim was to quantify acute IABP effects on the mechanical properties of muscular arteries in induced acute heart failure (AHF), before and after adventitia removal. Pressure and diameter were recorded in the iliac arteries (IA) of sheep (n = 7), before and during 1:2 IABP: (i) in control state (CS) with intact IA, (ii) in CS after IA adventitia removal, and (iii) in de-adventitialized IA after AHF. Conduit function, compliance and arterial distensibility were calculated in each state. During CS, IABP resulted in intact IA dilatation and in an increase in conduit function, compliance and distensibility; adventitial removal determined an increase of arterial stiffness with respect to the CS, which decreased when IABP was used; the increase in arterial stiffness observed after adventitia removal was also detected in AHF state; IABP improves conduit function and arterial stiffness in de-adventitialized arteries, both before and during AHF. However, the improvement in these properties was lower than in intact arteries. Before and after AHF induction, the improvements of conduit function and arterial distensibility determined by IABP in intact IA were significantly reduced after adventitia removal. Adventitial layer integrity would be necessary to maximize IABP-related beneficial effects on arterial system properties. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

Bilateral Internal Carotid Artery Occlusion, External Carotid Artery Stenosis, and Vertebral Artery Kinking: May It Be Asymptomatic?

Science.gov (United States)

Fatic, Nikola; Jaffer, Usman; Ivana, Saicic; Gordana, Globarevic-Vukcevic; Markovic, Dragan; Kostic, Dusan; Davidovic, Lazar

2017-10-01

The clinical spectrum of internal carotid artery occlusion ranges from being a completely asymptomatic occlusion to a devastating stroke or death. The prevalence of asymptomatic internal carotid artery occlusion is unknown, particularly for bilateral occlusion. The distal branches of the external carotid artery anastomose with distal branches of the internal carotid artery provide important sources of collateral circulation to the brain. Stenosis of the external carotid artery with ipsilateral/bilateral internal occlusion may result in ischemic sequelae. Coiling or kinking of the vertebral artery is a rare morphological entity that is infrequently reported because it remains asymptomatic and has no clinical relevance. Currently, there is little evidence to support management strategies for this disease entity and no official recommendations for asymptomatic bilateral carotid artery occlusion. We present a case of a 62-year-old female with asymptomatic bilateral internal carotid artery occlusion, bilateral external carotid artery stenoses, and bilateral kinking of the vertebral artery at the V2 segment, who has been successfully managed conservatively for over 5 years. An individualized approach to management of patients with bilateral internal carotid artery occlusion, especially in combination with external carotid artery stenosis and elongation malformations of the vertebral artery is key to a successful strategy. Copyright © 2017 Elsevier Inc. All rights reserved.

Superselective intra-arterial infusion via the superficial temporal artery and occipital artery for gingival carcinoma of the mandible. Simultaneous catheter placement to the maxillary artery and facial artery

International Nuclear Information System (INIS)

Iwai, Toshinori; Mitsudo, Kenji; Fukui, Takafumi

2009-01-01

Superselective intra-arterial infusion via the superficial temporal artery (STA) has become useful for oral cancer. Approaching via the occipital artery (OA) enables superselective intra-arterial infusion when catheter placement via the STA is impossible. Therefore, simultaneous catheter placement via the STA and OA is possible. We report a surgical method of simultaneous catheter placement via the STA and OA to achieve retrograde superselective intra-arterial infusion for gingival carcinoma of the mandible. Preoperatively, three-dimensional computed tomography angiography was performed to identify the route of the external carotid artery and branches such as the STA, OA, maxillary artery, and facial artery (FA). Thirteen patients with mandibular gingival cancer underwent catheter placement via the STA and OA under local anesthesia. Catheter placement via the STA and OA was superselectively successful in all the patients. The mean operating time was 150.8 min. Catheter placed to the FA via the OA was dislocated during the treatment in one patient, and so the catheter was replaced. This method is useful to enable superselective intra-arterial chemotherapy to the whole gingival carcinoma of the mandible from the start of treatment compared with approaching via the STA. (author)

Lung volumes, ventricular function and pulmonary arterial flow in children operated on for left-sided congenital diaphragmatic hernia: long-term results

International Nuclear Information System (INIS)

Abolmaali, Nasreddin; Koch, Arne; Goetzelt, Knut; Vogelberg, Christian; Hahn, Gabriele; Fitze, Guido

2010-01-01

To compare MRI-based functional pulmonary and cardiac measurements in the long-term follow-up of children operated on for left-sided congenital diaphragmatic hernia (CDH) with age- and body size-matched healthy controls. Twelve children who received immediate postnatal surgery for closure of isolated left-sided CDH were included and received basic medical examinations, pulmonary function testing and echocardiography. MRI included measurement of lung volume, ventricular function assessment and velocity-encoded imaging of the pulmonary arteries and was compared with the data for 12 healthy children matched for age and body size. While patients' clinical test results were not suspicious, comparison between the MRI data for patients and those for healthy controls revealed significant differences. In patients, the volumes of the left lungs were increased and the tidal volume was larger on the right side. While the stroke volumes of both ventricles were reduced, heart rate and ejection fraction were increased. Flow, acceleration time and cross-sectional area of the left pulmonary artery were reduced. Functional MRI detected pulmonary and cardiac findings in the late follow-up of CDH children which may be missed by standard clinical methods and might be relevant for decisions regarding late outcome and treatment. (orig.)

Lung volumes, ventricular function and pulmonary arterial flow in children operated on for left-sided congenital diaphragmatic hernia: long-term results

Energy Technology Data Exchange (ETDEWEB)

Abolmaali, Nasreddin; Koch, Arne [Dresden University of Technology, OncoRay - Molecular and Biological Imaging, Medical Faculty Carl Gustav Carus, Dresden (Germany); Goetzelt, Knut; Vogelberg, Christian [University Clinics Carl Gustav Carus, Dresden University of Technology, Clinic and Policlinic for Pediatrics - Pediatric Pulmonology, Dresden (Germany); Hahn, Gabriele [University Clinics Carl Gustav Carus, Dresden University of Technology, Institute and Policlinic for Radiology - Pediatric Radiology, Dresden (Germany); Fitze, Guido [University Clinics Carl Gustav Carus, Dresden University of Technology, Clinic and Policlinic for Pediatric Surgery, Dresden (Germany)

2010-07-15

To compare MRI-based functional pulmonary and cardiac measurements in the long-term follow-up of children operated on for left-sided congenital diaphragmatic hernia (CDH) with age- and body size-matched healthy controls. Twelve children who received immediate postnatal surgery for closure of isolated left-sided CDH were included and received basic medical examinations, pulmonary function testing and echocardiography. MRI included measurement of lung volume, ventricular function assessment and velocity-encoded imaging of the pulmonary arteries and was compared with the data for 12 healthy children matched for age and body size. While patients' clinical test results were not suspicious, comparison between the MRI data for patients and those for healthy controls revealed significant differences. In patients, the volumes of the left lungs were increased and the tidal volume was larger on the right side. While the stroke volumes of both ventricles were reduced, heart rate and ejection fraction were increased. Flow, acceleration time and cross-sectional area of the left pulmonary artery were reduced. Functional MRI detected pulmonary and cardiac findings in the late follow-up of CDH children which may be missed by standard clinical methods and might be relevant for decisions regarding late outcome and treatment. (orig.)

Lung volumes, ventricular function and pulmonary arterial flow in children operated on for left-sided congenital diaphragmatic hernia: long-term results.

Science.gov (United States)

Abolmaali, Nasreddin; Koch, Arne; Götzelt, Knut; Hahn, Gabriele; Fitze, Guido; Vogelberg, Christian

2010-07-01

To compare MRI-based functional pulmonary and cardiac measurements in the long-term follow-up of children operated on for left-sided congenital diaphragmatic hernia (CDH) with age- and body size-matched healthy controls. Twelve children who received immediate postnatal surgery for closure of isolated left-sided CDH were included and received basic medical examinations, pulmonary function testing and echocardiography. MRI included measurement of lung volume, ventricular function assessment and velocity-encoded imaging of the pulmonary arteries and was compared with the data for 12 healthy children matched for age and body size. While patients' clinical test results were not suspicious, comparison between the MRI data for patients and those for healthy controls revealed significant differences. In patients, the volumes of the left lungs were increased and the tidal volume was larger on the right side. While the stroke volumes of both ventricles were reduced, heart rate and ejection fraction were increased. Flow, acceleration time and cross-sectional area of the left pulmonary artery were reduced. Functional MRI detected pulmonary and cardiac findings in the late follow-up of CDH children which may be missed by standard clinical methods and might be relevant for decisions regarding late outcome and treatment.

Arterial wave intensity and ventricular-arterial coupling by vascular ultrasound: rationale and methods for the automated analysis of forwards and backwards running waves.

Science.gov (United States)

Rakebrandt, F; Palombo, C; Swampillai, J; Schön, F; Donald, A; Kozàkovà, M; Kato, K; Fraser, A G

2009-02-01

Wave intensity (WI) in the circulation is estimated noninvasively as the product of instantaneous changes in pressure and velocity. We recorded diameter as a surrogate for pressure, and velocity in the right common carotid artery using an Aloka SSD-5500 ultrasound scanner. We developed automated software, applying the water hammer equation to obtain local wave speed from the slope of a pressure/velocity loop during early systole to separate net WI into individual forwards and backwards-running waves. A quality index was developed to test for noisy data. The timing, duration, peak amplitude and net energy of separated WI components were measured in healthy subjects with a wide age range. Age and arterial stiffness were independent predictors of local wave speed, whereas backwards-travelling waves correlated more strongly with ventricular systolic function than with age-related changes in arterial stiffness. Separated WI offers detailed insight into ventricular-arterial interactions that may be useful for assessing the relative contributions of ventricular and vascular function to wave travel.

Transcatheter Arterial Infusion of Autologous CD133+ Cells for Diabetic Peripheral Artery Disease

Directory of Open Access Journals (Sweden)

Xiaoping Zhang

2016-01-01

Full Text Available Microvascular lesion in diabetic peripheral arterial disease (PAD still cannot be resolved by current surgical and interventional technique. Endothelial cells have the therapeutic potential to cure microvascular lesion. To evaluate the efficacy and immune-regulatory impact of intra-arterial infusion of autologous CD133+ cells, we recruited 53 patients with diabetic PAD (27 of CD133+ group and 26 of control group. CD133+ cells enriched from patients’ PB-MNCs were reinfused intra-arterially. The ulcer healing followed up till 18 months was 100% (3/3 in CD133+ group and 60% (3/5 in control group. The amputation rate was 0 (0/27 in CD133+ group and 11.54% (3/26 in control group. Compared with the control group, TcPO2 and ABI showed obvious improvement at 18 months and significant increasing VEGF and decreasing IL-6 level in the CD133+ group within 4 weeks. A reducing trend of proangiogenesis and anti-inflammatory regulation function at 4 weeks after the cells infusion was also found. These results indicated that autologous CD133+ cell treatment can effectively improve the perfusion of morbid limb and exert proangiogenesis and anti-inflammatory immune-regulatory impacts by paracrine on tissue microenvironment. The CD133+ progenitor cell therapy may be repeated at a fixed interval according to cell life span and immune-regulatory function.

Retinal artery occlusion during carotid artery stenting with distal embolic protection device.

Science.gov (United States)

Kohara, Kotaro; Ishikawa, Tatsuya; Kobayashi, Tomonori; Kawamata, Takakazu

2018-01-01

Retinal artery occlusion associated with carotid artery stenosis is well known. Although it can also occur at the time of carotid artery stenting, retinal artery occlusion via the collateral circulation of the external carotid artery is rare. We encountered two cases of retinal artery occlusion that were thought to be caused by an embolus from the external carotid artery during carotid artery stenting with a distal embolic protection device for the internal carotid artery. A 71-year-old man presented with central retinal artery occlusion after carotid artery stenting using the Carotid Guardwire PS and a 77-year-old man presented with branch retinal artery occlusion after carotid artery stenting using the FilterWire EZ. Because additional new cerebral ischaemic lesions were not detected in either case by postoperative diffusion-weighted magnetic resonance imaging, it was highly likely that the debris that caused retinal artery occlusion passed through not the internal carotid artery but collaterals to retinal arteries from the external carotid artery, which was not protected by a distal embolic protection device. It is suggested that a distal protection device for the internal carotid artery alone cannot prevent retinal artery embolisation during carotid artery stenting and protection of the external carotid artery is important to avoid retinal artery occlusion.

[Cognitive disturbances in patients with arterial hypertension].

Science.gov (United States)

Starchina, Iu A; Parfenov, V A; Chazova, I E; Pustovitova, T S; Iakhno, N N

2008-01-01

Memory impairment, headaches and vertigo are considered as initial appearances of chronic cerebral vascular disorder in patients with arterial hypertension (AH). The complex analysis of complaints, cognitive functioning, emotional state and MRI data was conducted in 60 patients with AH, mean age 58,4+/-7,8 years, without a history of stroke and 30 controls matched for age, sex and education. Impairment of cognitive functioning was assessed by the Psychiatric Status Scale (a short version), the Clock Drawing Test, tests of auditory and verbal memory, attention concentration, speed of test performance, speech fluency and spatial orientation. The deterioration effect of systolic arterial pressure on cognitive functioning was found. The lesions of white matter (subcortical and/or periventricular leucoaraiosis) were observed in 76% of patients and single asymptomatic lacunar infarctions--in 20%. Cerebral vascular lesions were correlated with cognitive impairment. Anxiety and anxiety-depressive disorders which were not associated with the cerebral vascular lesion but related in large to the patient's complaints on headaches and vertigo were revealed in 62% of cases. The results of the study suggest that cognitive dysfunction proves to be the early and reliable predictor of chronic cerebral vascular disorder in patients with arterial hypertension.

Systemic Arterial-to-Pulmonary Artery Shunt Utilization

African Journals Online (AJOL)

multiruka1

In certain circumstances, such as cyanotic neonates with tetralogy of Fallot (4) or cyanotic patients with. Tetralogy of Fallot and hypoplastic pulmonary arteries. (5), better outcomes are obtained if definitive surgery. (total correction or palliation) is preceded by creation of a systemic arterial-to-pulmonary artery shunt (SAPAS).

Carotid artery stiffness evaluated early by wave intensity in normal left ventricular function in post-radiotherapy patients with nasopharyngeal carcinoma.

Science.gov (United States)

Zhang, Zhuo; Luo, Runlan; Tan, Bijun; Qian, Jing; Duan, Yanfang; Wang, Nan; Li, Guangsen

2018-04-01

This study aims to assess carotid elasticity early in normal left ventricular function in post-radiotherapy patients with nasopharyngeal carcinoma (NPC) by wave intensity. Sixty-seven post-radiotherapy patients all with normal left ventricular function were classified into group NPC1 and group NPC2 based on their carotid intima-media thickness. Thirty age- and sex-matched NPC patients without any history of irradiation and chemotherapy were included as a control group. Carotid parameters, including stiffness constant (β), pressure-strain elastic modulus (Ep), arterial compliance (AC), stiffness constant pulse wave velocity (PWVβ), and wave intensity pulse wave velocity (PWVWI) were measured. There were no significant differences in conventional echocardiographic variables among the three groups. In comparison with the control group, β, Ep, PWVβ, and PWVWI were significantly increased, while AC was significantly decreased in the NPC1 and NPC2 groups, and there were differences between the NPC1 group and NPC2 group (all P < 0.05). This study suggested that carotid artery stiffness increased with reduced carotid compliance in post-RT with NPC.

Relation of epicardial adipose tissue with arterial compliance and stiffness in patients with hypertension.

Science.gov (United States)

Korkmaz, Levent; Cirakoglu, Omer Faruk; Ağaç, Mustafa Tarik; Erkan, Hakan; Korkmaz, Ayca Ata; Acar, Zeydin; Kul, Selim; Hatem, Engin; Çelik, Şükrü

2014-09-01

The main aim of the present study was to investigate the association between epicardial adipose tissue (EAT) and arterial function in patients with asymptomatic hypertension. Patients with hypertension (n = 155) were enrolled consecutively. Patients with decreased arterial compliance (AC) and increased cardioankle vascular index (CAVI) had higher EAT values compared with those with normal AC and CAVI (6.23 ± 1.67 vs 4.91 ± 1.40, P arterial function in patients with asymptomatic hypertension. The link between EAT and arterial stiffness deserves further investigation. © The Author(s) 2013.

Relation between preoperative autonomic function and blood pressure change after tourniquet deflation during total knee replacement arthroplasty.

Science.gov (United States)

Huh, In Young; Kim, Dae-Young; Lee, Ji-Hyeon; Shin, Soo Jin; Cho, Young Woo; Park, Soon Eun

2012-02-01

Tourniquets are used to provide a bloodless surgical field for extremities. Hypotension due to vasodilation and bleeding after tourniquet deflation is a common event. Hemodynamic stability is modulated by the autonomic nervous system (ANS). Heart rate variability (HRV) is a sensitive method for detecting individuals who may be at risk of hemodynamic instability during general anesthesia. The purpose of this study was to investigate ANS function to predict hypotension after tourniquet deflation. Eighty-six patients who underwent total knee replacement arthroplasty (TKRA) were studied. HRV, systolic blood pressure variability (SBPV) and baroreflex sensitivity (BRS) were analyzed. We assigned two groups depending on the lowest systolic blood pressure (SBP) or mean BP (MBP) after tourniquet release (Group H; SBP 80 mmHg and MBP > 60 mmHg). Fifteen patients developed severe hypotension and ten patients were treated with ephedrine. Of the parameters of HRV, SBPV, and BRS, only BRS(SEQ) was significant being low in Group H. BRS and high-frequency SBPV were correlated with the degree of MBP change after tourniquet deflation. Preoperative low BRS is associated with hypotension after tourniquet deflation, suggesting the importance of baroreflex regulation for intraoperative hemodynamic stability.

Modeling the Afferent Dynamics of the Baroreflex Control System

DEFF Research Database (Denmark)

Ottesen, Johnny T.; Mahdi, Adam; Sturdy, Jacob

2013-01-01

of mechanoreceptors located in the BR nerve-endings, and modulation of the action potential frequency. The three sub-systems are modeled individually following well-established biological principles. The first submodel, predicting arterial wall deformation, uses blood pressure as an input and outputs circumferential...... demonstrate that our preferred model can exhibit all known dynamics and that it is advantageous to combine qualitative and quantitative analysis methods....

Proximal Versus Distal Splenic Artery Embolisation for Blunt Splenic Trauma: What is the Impact on Splenic Immune Function?

International Nuclear Information System (INIS)

Foley, P. T.; Kavnoudias, H.; Cameron, P. U.; Czarnecki, C.; Paul, E.; Lyon, S. M.

2015-01-01

PurposeTo compare the impact of proximal or distal splenic artery embolisation versus that of splenectomy on splenic immune function as measured by IgM memory B cell levels.Materials and MethodsPatients with splenic trauma who were treated by splenic artery embolisation (SAE) were enrolled. After 6 months splenic volume was assessed by CT, and IgM memory B cells in peripheral blood were measured and compared to a local normal reference population and to a post-splenectomy population.ResultsOf the 71 patients who underwent embolisation, 38 underwent proximal embolisation, 11 underwent distal embolisation, 22 patients were excluded, 1 had both proximal and distal embolisation, 5 did not survive and 16 did not return for evaluation. There was a significant difference between splenectomy and proximal or distal embolisation and a trend towards greater preservation of IgM memory B cell number in those with distal embolisation—a difference that could not be attributed to differences in age, grade of injury or residual splenic volume.ConclusionIgM memory B cell levels are significantly higher in those treated with SAE compared to splenectomy. Our data provide evidence that splenic embolisation should reduce immunological complications of spleen trauma and suggest that distal embolisation may maintain better function

Proximal Versus Distal Splenic Artery Embolisation for Blunt Splenic Trauma: What is the Impact on Splenic Immune Function?

Energy Technology Data Exchange (ETDEWEB)

Foley, P. T., E-mail: pfoley@doctors.org.uk [The Canberra Hospital, Department of Medical Imaging (Australia); Kavnoudias, H., E-mail: h.kavnoudias@alfred.org.au [The Alfred Hospital, Radiology Research Unit, Radiology Department (Australia); Cameron, P. U., E-mail: paul.cameron@unimelb.edu.au [The Alfred Hospital, Infectious Diseases Unit (Australia); Czarnecki, C., E-mail: caroline.czarnecki@gmail.com [Royal Melbourne Hospital, Radiology Department (Australia); Paul, E., E-mail: eldho.paul@monash.edu [Monash University, Department of Epidemiology & Preventive Medicine, School of Public Health and Preventive Medicine, Alfred Hospital (Australia); Lyon, S. M., E-mail: lyonsey@optusnet.com.au [Melbourne Endovascular (Australia)

2015-10-15

PurposeTo compare the impact of proximal or distal splenic artery embolisation versus that of splenectomy on splenic immune function as measured by IgM memory B cell levels.Materials and MethodsPatients with splenic trauma who were treated by splenic artery embolisation (SAE) were enrolled. After 6 months splenic volume was assessed by CT, and IgM memory B cells in peripheral blood were measured and compared to a local normal reference population and to a post-splenectomy population.ResultsOf the 71 patients who underwent embolisation, 38 underwent proximal embolisation, 11 underwent distal embolisation, 22 patients were excluded, 1 had both proximal and distal embolisation, 5 did not survive and 16 did not return for evaluation. There was a significant difference between splenectomy and proximal or distal embolisation and a trend towards greater preservation of IgM memory B cell number in those with distal embolisation—a difference that could not be attributed to differences in age, grade of injury or residual splenic volume.ConclusionIgM memory B cell levels are significantly higher in those treated with SAE compared to splenectomy. Our data provide evidence that splenic embolisation should reduce immunological complications of spleen trauma and suggest that distal embolisation may maintain better function.

Proximal Versus Distal Splenic Artery Embolisation for Blunt Splenic Trauma: What is the Impact on Splenic Immune Function?

Science.gov (United States)

Foley, P T; Kavnoudias, H; Cameron, P U; Czarnecki, C; Paul, E; Lyon, S M

2015-10-01

To compare the impact of proximal or distal splenic artery embolisation versus that of splenectomy on splenic immune function as measured by IgM memory B cell levels. Patients with splenic trauma who were treated by splenic artery embolisation (SAE) were enrolled. After 6 months splenic volume was assessed by CT, and IgM memory B cells in peripheral blood were measured and compared to a local normal reference population and to a post-splenectomy population. Of the 71 patients who underwent embolisation, 38 underwent proximal embolisation, 11 underwent distal embolisation, 22 patients were excluded, 1 had both proximal and distal embolisation, 5 did not survive and 16 did not return for evaluation. There was a significant difference between splenectomy and proximal or distal embolisation and a trend towards greater preservation of IgM memory B cell number in those with distal embolisation-a difference that could not be attributed to differences in age, grade of injury or residual splenic volume. IgM memory B cell levels are significantly higher in those treated with SAE compared to splenectomy. Our data provide evidence that splenic embolisation should reduce immunological complications of spleen trauma and suggest that distal embolisation may maintain better function.

Impact of hypertension severity on arterial stiffness, cerebral vasoreactivity, and cognitive performance

Science.gov (United States)

Muela, Henrique Cotchi Simbo; Costa-Hong, Valeria A.; Yassuda, Monica Sanches; Machado, Michel Ferreira; Nogueira, Ricardo de Carvalho; Moraes, Natalia C.; Memória, Claudia Maia; Macedo, Thiago A.; Bor-Seng-Shu, Edson; Massaro, Ayrton Roberto; Nitrini, Ricardo; Bortolotto, Luiz A.

2017-01-01

ABSTRACT. Aging, hypertension (HTN), and other cardiovascular risk factors contribute to structural and functional changes of the arterial wall. Objective: To evaluate whether arterial stiffness (AS) is related to cerebral blood flow changes and its association with cognitive function in patients with hypertension. Methods: 211 patients (69 normotensive and 142 hypertensive) were included. Patients with hypertension were divided into 2 stages: HTN stage-1 and HTN stage-2. The mini-mental state examination (MMSE), Montreal Cognitive Assessment (MoCA) and a battery of neuropsychological (NPE) tests were used to determine cognitive function. Pulse wave velocity was measured using the Complior®. Carotid properties were assessed by radiofrequency ultrasound. Central arterial pressure and augmentation index were obtained using applanation tonometry. Middle cerebral artery flow velocity was measured by transcranial Doppler ultrasonography. Results: Both arterial stiffness parameters and cerebral vasoreactivity worsened in line with HTN severity. There was a negative correlation between breath holding index (BHI) and arterial stiffness parameters. Cognitive performance worsened in line with HTN severity, with statistical difference occurring mainly between the HTN-2 and normotension groups on both the MMSE and MoCA. The same tendency was observed on the NPE tests. Conclusion: Hypertension severity was associated with higher AS, worse BHI, and lower cognitive performance. PMID:29354219

Uterine artery chemoembolization: its application in treating cervical pregnancy

International Nuclear Information System (INIS)

Zhang Guofu; Shang Mingyi; Tian Xiaomei; Han Zhigang; Wang Xuezhen; Wang Dongyan; Huang Zirong; Xu Congjian

2009-01-01

Objective: To discuss the feasibility and safety of uterine artery chemoembolization in the treatment of cervical pregnancy. Methods: During the period of Sep. 2005-Dec. 2007, uterine artery chemoemboliztion was performed in 12 patients with cervical pregnancy in the authors' hospital. Via bilateral uterine arteries 100 mg MTX and 80,000 U Gentamycin were infused separately, after that the bilateral uterine arteries were embolized with gelfoam. Cleaning of the uterus and the cervix uteri was carried out in 24 -72 h after the procedure. Results: The technical success rate of bilateral uterine artery chemoembolization was 100%. The blood loss was 50-100 ml (mean 65 ml) during the procedure of cleaning the uterus and the cervix uteri. No serious complications occurred. Conclusion: Uterine artery chemoembolization is an effective and safe treatment for cervical pregnancy, which can greatly avoid unnecessary uterectomy and preserve fertility function. (authors)

An unusual neonatal presentation of anomalous origin of the left coronary artery arising from the pulmonary artery.

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Garty, Y; Guri, A; Shinwell, E S; Matitiau, A

2008-01-01

We describe a previously unreported neonatal presentation of an anomalous origin of the left coronary artery arising from the pulmonary artery. This is a full-term female infant after normal pregnancy and delivery. The baby was diagnosed at 2 days of age due to weak femoral pulses noted on the routine nursery discharge examination. The cardiac examination revealed weak pulses everywhere and mild tachypnea and tachycardia. An electrocardiogram showed clear signs of ischemia. Echocardiography demonstrated an anomalous origin of the left coronary artery arising from the pulmonary artery with bidirectional blood flow. There was a severely depressed left ventricular function and mild mitral valve regurgitation. At 4 days of age, the infant underwent complete successful surgical repair with reimplantation of the anomalous coronary artery to the aorta. She recovered slowly but well. Fifteen months later she is doing well with no cardiac residua. A neonatal presentation is very unusual due to protective high pulmonary resistance after birth, with gradual decline in pressure and gradual onset of heart failure. This case may be related to an unusually rapid drop in pulmonary vascular resistance causing very early cardiac ischemia. (c) 2007 S. Karger AG, Basel.

Unusual Survival of Anomalous Left Coronary Artery From the Pulmonary Artery With Severe Rheumatic Mitral Stenosis in Septuagenarian Women: Foes Becoming Friends?

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Sinha, Santosh Kumar; Khanra, Dibbendhu; Jha, Mukesh Jitendra; Singh, Karandeep; Razi, Mahamdulla; Goel, Amit; Mishra, Vikas; Asif, Mohammad; Sachan, Mohit; Afdaali, Nasar; Kumar, Ashutosh; Thakur, Ramesh; Krishna, Vinay; Pandey, Umeshwar; Varma, Chandra Mohan

2016-10-01

ALCAPA syndrome (anomalous origin of the left coronary artery from the pulmonary artery) is a rare disease but lethal with clinical expression from myocardial infarction, congestive heart failure to death during early infancy and unusual survival to adulthood. We report a 73-year-old woman with ALCAPA who presented with exertional dyspnea (NYHA functional class II) over past 2 years. Physical examination revealed soft S, long mid diastolic rumbling murmur and apical pan-systolic murmur. Electrocardiography displayed biatrial enlargement and poor R progression and normal sinus rhythm. Echocardiography established calcified severe mitral stenosis (MS), presence of continuous flow entering the pulmonary trunk, turbulent continuous flow in inter-ventricular septum with left to right shunt in contrast echocardiography and normal systolic function. Coronary angiogram showed absence of left coronary artery (LCA) originating from aorta, dilated and tortuous right coronary artery (RCA) and abundant Rentrop grade 3 intercoronary collateral communicating with LCA originating from pulmonary trunk which was also confirmed on coronary CT angiogram thus establishing diagnosis of ALCAPA. It is exceedingly rare to be associated with severe MS. However, such a long survival in our patient can be explained by the severe pulmonary arterial hypertension which may be contributing to lesser coronary steal.

Maternal Arterial Murmur in Pregnancy

DEFF Research Database (Denmark)

Riknagel, Diana

2017-01-01

Alternative methods of assessing the placental function are called for in the attempt to clarify the pathophysiology behind adverse pregnancy outcome as fetal growth restriction. A new concept of using cardiovascular sounds emitted near the uterine arteries in pregnancy is investigated...

Beneficial effects of prolonged blood pressure control after carotid artery stenting

Directory of Open Access Journals (Sweden)

Chang A

2017-01-01

positive correlations between the mean or maximal SBP reductions 6 h post-CAS and SBP reductions 1 year post-CAS (β =0.20±0.07, P=0.0067 and β =0.47±0.10, P<0.0001, respectively. Conclusion: As compared to medical treatment alone, CAS may provide significant beneficial effect on long-term BP control 1 year post-CAS. Furthermore, SBP reductions 6 h post-CAS may predict the SBP reductions 1 year post-CAS. Keywords: carotid artery stenosis, hemodynamics, cerebral autoregulation, baroreflex, post-stenting hypotension, antihypertensive agents

TEVAR and covering the celiac artery. Is it safe or not?

DEFF Research Database (Denmark)

Falkenberg, Morten; Lönn, Lars Birger; Schroeder, Torben Veith

2010-01-01

artery. In the latter case, adequate collateral supply to the upper gastrointestinal tract is crucial. Collateral arteries joining the celiac and the superior mesenteric arteries are well characterized in patients with chronic celiac stenosis or occlusion. Are these collateral pathways sufficient also...... for sudden iatrogenic closure of the celiac artery? By performing a preoperative angiography of the superior mesenteric artery with temporary balloon occlusion of the celiac artery, collateral capacity between the two vessels can be tested in advance. Exact positioning of the distal end of a large thoracic...... together, in the large majority of patients, it appears that intentional celiac coverage can be done safely provided that sufficient collateral function have been demonstrated in advance....

Left coronary arterial blood flow: Noninvasive detection by Doppler US

International Nuclear Information System (INIS)

Gramiak, R.; Holen, J.; Moss, A.J.; Gutierrez, O.H.; Picone, A.L.; Roe, S.A.

1986-01-01

Continuous wave (CW) and pulsed Doppler ultrasound studies with spectral analysis were used to detect the left coronary arterial blood flow in patients who were undergoing routine echocardiography. The pulmonary artery is a stable ultrasonic landmark from which detection of the blood flow can be effected. The left coronary artery can be distinguished by its blood flow toward the cardiac apex and by specific, functional flow features. Flow patterns vary among the left main, circumflex, and anterior descending arteries; patterns also vary with respiration cycles. In the present study, coronary arterial blood flow was detected in 58 of 70 patients (83%). Findings were validated by selectively injecting an agitated saline contrast medium into the left coronary artery and, in another study, by comparing human Doppler phasic flow waveforms with electromagnetic flowmeter recordings obtained in dogs

Testicular artery arising from an aberrant right renal artery | Suluba ...

African Journals Online (AJOL)

This case report we discovered the rare variation of the origin of the right testicular artery arising from the right aberrant renal artery with double renal artery irrigating both left and right kidneys. These variations in the testicular arteries and renal arteries have implication to surgical procedures such as orchidopexy repair for ...

Inflammatory processes during arteriogenesis : the contribution of the innate immune system to collateral artery growth

NARCIS (Netherlands)

de Groot, D.

2011-01-01

The central theme of the work presented in the thesis is restoration of tissue perfusion by collateral artery growth. During collateral artery growth, or arteriogenesis, unused pre-existing vascular anastomoses remodel into functional arteries. These arteries are able to take over the perfusion of

Long-term diet-induced hypertension in rats is associated with reduced expression and function of small artery SKCa, IKCa, and Kir2.1 channels

DEFF Research Database (Denmark)

Gradel, Anna Katrina Jógvansdóttir; Salomonsson, Max; Sørensen, Charlotte Mehlin

2018-01-01

in long-term diet-induced hypertension in rats. Hypothesis: A 28-week diet rich in fat, fructose, or both, will lead to changes in K+ transporter expression and function, which is associated with increased blood pressure and decreased arterial function. Methods and Results: Male Sprague Dawley rats......RNA expression of vascular K+ transporters, and vessel myography in small mesenteric arteries. BW was increased in the High Fat and High Fat/Fruc groups, and SBP was increased in the High Fat/Fruc group. mRNA expression of SKCa, IKCa, and Kir2.1 K+ channels were reduced in the High Fat/Fruc group. Reduced EDH......-type relaxation to acetylcholine was seen in the High Fat and High Fat/Fruc groups. Ba2+-sensitive dilatation to extracellular K+ was impaired in all experimental diet groups. Conclusions: Reduced expression and function of SKCa, IKCa and Kir2.1 channels is associated with elevated blood pressure in rats fed...

Monocytic microRNA profile associated with coronary collateral artery function in chronic total occlusion patients.

Science.gov (United States)

Hakimzadeh, Nazanin; Elias, Joëlle; Wijntjens, Gilbert W M; Theunissen, Ruud; van Weert, Angela; Smulders, Martijn W; van den Akker, Nynke; Moerland, Perry D; Verberne, Hein J; Hoebers, Loes P; Henriques, Jose P S; van der Laan, Anja M; Ilhan, Mustafa; Post, Mark; Bekkers, Sebastiaan C A M; Piek, Jan J

2017-05-08

An expansive collateral artery network is correlated with improved survival in case of adverse cardiac episodes. We aimed to identify cellular microRNAs (miRNA; miR) important for collateral artery growth. Chronic total occlusion (CTO) patients (n = 26) were dichotomized using pressure-derived collateral flow index (CFI p ) measurements; high collateral capacity (CFI p  > 0.39; n = 14) and low collateral (CFI p  collateral capacity patients. Validation by real-time polymerase chain reaction demonstrated significantly decreased expression of miR339-5p in all stimulated monocyte phenotypes of low collateral capacity patients. MiR339-5p showed significant correlation with CFI p values in stimulated monocytes. Ingenuity pathway analysis of predicted gene targets of miR339-5p and differential gene expression data from high versus low CFI p patients (n = 20), revealed significant association with STAT3 pathway, and also suggested a possible regulatory role for this signaling pathway. These results identify a novel association between miR339-5p and coronary collateral function. Future work examining modulation of miR339-5p and downstream effects on the STAT3 pathway and subsequent collateral vessel growth are warranted.

Pulmonary Arterial Hypertension and Neonatal Arterial Switch Surgery for Correction of Transposition of the Great Arteries.

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Domínguez Manzano, Paula; Mendoza Soto, Alberto; Román Barba, Violeta; Moreno Galdó, Antonio; Galindo Izquierdo, Alberto

2016-09-01

There are few reports of the appearance of pulmonary arterial hypertension following arterial switch surgery in the neonatal period to correct transposition of the great arteries. We assessed the frequency and clinical pattern of this complication in our series of patients. Our database was reviewed to select patients with transposition of the great arteries corrected by neonatal arterial switch at our hospital and who developed pulmonary hypertension over time. We identified 2 (1.3%) patients with transposition of the great arteries successfully repaired in the first week of life who later experienced pulmonary arterial hypertension. The first patient was a 7-year-old girl diagnosed with severe pulmonary hypertension at age 8 months who did not respond to medical treatment and required lung transplantation. The anatomic pathology findings were consistent with severe pulmonary arterial hypertension. The second patient was a 24-month-old boy diagnosed with severe pulmonary hypertension at age 13 months who did not respond to medical therapy. Pulmonary hypertension is a rare but very severe complication that should be investigated in all patients with transposition of the great arteries who have undergone neonatal arterial switch, in order to start early aggressive therapy for affected patients, given the poor therapeutic response and poor prognosis involved. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Successful flow reduction surgery for a ruptured true posterior communicating artery aneurysm caused by the common carotid artery ligation for epistaxis.

Science.gov (United States)

Yamao, Yukihiro; Takahashi, Jun C; Satow, Tetsu; Iihara, Koji; Miyamoto, Susumu

2014-01-01

Carotid artery occlusion can lead to the development of rare true posterior communicating artery (PCoA) aneurysms because of hemodynamic stress on the PCoA. Surgical treatment of these lesions is challenging. The authors report a case of a true PCoA aneurysm that developed and ruptured 37 years after ligation of the ipsilateral common carotid artery for epistaxis. The lesion was successfully treated with clipping of the distal M1 segment of the middle cerebral artery (MCA) after the occipital artery-radial artery free graft-MCA bypass, which led to extreme reduction in collateral flow through the PCoA. A cortical branch, located just proximal to the obliteration site, functioned as a sufficient flow outlet. The aneurysm shrank, and the patient has been doing well without any symptoms for 5 years after surgery. M1 obliteration combined with high-flow extra-intracranial bypass might be a promising option for a true PCoA aneurysm, and therapeutic design that leaves a sufficient flow outlet on the M1 is mandatory to avoid unexpected occlusion of the M1 and its perforators.

Evaluation of Factors Influencing Liver Function Test in On-Pump Coronary Artery Bypass Graft Surgery

Directory of Open Access Journals (Sweden)

Shahrbano Shahbazi

2013-12-01

Full Text Available Background: Liver dysfunction during on-pump coronary artery bypass graft surgery (CABG is a rare complication but is associated with significant morbidity and mortality. The ability to identify high-risk patients may be helpful in planning appropriate management strategies. We aimed to evaluate the factors influencing liver function tests during on-pump CABG. Methods: In 146 patients scheduled for on-pump CABG, the liver function test was done preoperatively and on the first postoperative day. Some preoperative and intraoperative risk factors were checked and then the postoperative liver function tests were compared with the preoperative ones. Probable relationships between these changes and the preoperative and intraoperative risk factors were studied. Results: A medical history of diabetes had a significant relationship with the changes in direct bilirubin. Preoperative central venous pressure had a significant relationship with the changes in aspartate aminotransferase and alanine aminotransferase. Use of intra-aortic balloon pump and duration of aortic cross-clamp were significantly related to the changes in the liver function tests except for alanine aminotransferase and alkaline phosphatase. Conclusion: It seems that the techniques for the reduction of cardiopulmonary bypass and aortic cross-clamp duration may be useful to protect liver function. We recommend that a larger population of patients be studied to confirm these findings.

Analysis of Arterial Mechanics During Head-down Tilt Bed Rest

Science.gov (United States)

Elliot, Morgan; Martin, David S.; Westby, Christian M.; Stenger, Michael B.; Platts, Steve

2014-01-01

Arterial health may be affected by microgravity or ground based analogs of spaceflight, as shown by an increase in thoracic aorta stiffness1. Head-down tilt bed rest (HDTBR) is often used as a ground-based simulation of spaceflight because it induces physiological changes similar to those that occur in space2, 3. This abstract details an analysis of arterial stiffness (a subclinical measure of atherosclerosis), the distensibility coefficient (DC), and the pressure-strain elastic modulus (PSE) of the arterial walls during HDTBR. This project may help determine how spaceflight differentially affects arterial function in the upper vs. lower body.

Computer model analysis of the radial artery pressure waveform.

Science.gov (United States)

Schwid, H A; Taylor, L A; Smith, N T

1987-10-01

Simultaneous measurements of aortic and radial artery pressures are reviewed, and a model of the cardiovascular system is presented. The model is based on resonant networks for the aorta and axillo-brachial-radial arterial system. The model chosen is a simple one, in order to make interpretation of the observed relationships clear. Despite its simplicity, the model produces realistic aortic and radial artery pressure waveforms. It demonstrates that the resonant properties of the arterial wall significantly alter the pressure waveform as it is propagated from the aorta to the radial artery. Although the mean and end-diastolic radial pressures are usually accurate estimates of the corresponding aortic pressures, the systolic pressure at the radial artery is often much higher than that of the aorta due to overshoot caused by the resonant behavior of the radial artery. The radial artery dicrotic notch is predominantly dependent on the axillo-brachial-radial arterial wall properties, rather than on the aortic valve or peripheral resistance. Hence the use of the radial artery dicrotic notch as an estimate of end systole is unreliable. The rate of systolic upstroke, dP/dt, of the radial artery waveform is a function of many factors, making it difficult to interpret. The radial artery waveform usually provides accurate estimates for mean and diastolic aortic pressures; for all other measurements it is an inadequate substitute for the aortic pressure waveform. In the presence of low forearm peripheral resistance the mean radial artery pressure may significantly underestimate the mean aortic pressure, as explained by a voltage divider model.

Evaluation of left ventricular myocardial function in patients with coronary artery disease and myocardial dysfunction before and after coronary artery bypass grafting by cine magnetic resonance imaging

International Nuclear Information System (INIS)

Juergens, K.U.; Renger, B.; Reimer, P.; Tombach, B.; Heindel, W.; Wichter, T.; Bruns, H.J.; Vahlhaus, C.; Janssen, F.W.; Breithardt, G.

2001-01-01

Purpose: To evaluate left ventricular (LV) myocardial function in ten patients with coronary artery disease (CAD) preoperatively and 6 months after coronary bypass grafting (CABG) by cardiac MRI. Material and methods: Ten patients (mean 65.2±5.9 years) with angiographically proven CAD and an indication for elective CABG underwent prospective evaluation of global LV function and regional wall motion by Cine-MRI at rest using a multiphase FLASH-2D sequence following regions of interest (ROI)-defined diagnostics of regional myocardial wall motion by means of levocardiography. Within the ROIs a total of 613 LV myocardial segments were analyzed preceding and following surgical revascularization. Results were compared with the data of 10 healthy volunteers. Results: Preoperatively, patients showed reduced stroke volume and ejection fraction compared with volunteers (p [de

Indirect Validation of Probe Speed Data on Arterial Corridors

Energy Technology Data Exchange (ETDEWEB)

Eshragh, Sepideh [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Young, Stanley E. [National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO 80401; Sharifi, Elham [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Hamedi, Masoud [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742; Sadabadi, Kaveh Farokhi [Center for Advanced Transportation Technology, University of Maryland, College Park, 5000 College Avenue, Suite 2206, College Park, MD 20742

2017-01-01

This study aimed to estimate the accuracy of probe speed data on arterial corridors on the basis of roadway geometric attributes and functional classification. It was assumed that functional class (medium and low) along with other road characteristics (such as weighted average of the annual average daily traffic, average signal density, average access point density, and average speed) were available as correlation factors to estimate the accuracy of probe traffic data. This study tested these factors as predictors of the fidelity of probe traffic data by using the results of an extensive validation exercise. This study showed strong correlations between these geometric attributes and the accuracy of probe data when they were assessed by using average absolute speed error. Linear models were regressed to existing data to estimate appropriate models for medium- and low-type arterial corridors. The proposed models for medium- and low-type arterials were validated further on the basis of the results of a slowdown analysis. These models can be used to predict the accuracy of probe data indirectly in medium and low types of arterial corridors.

An investigation of an autonomic innervation of the vertebral artery using monoamine histofluorescence

Directory of Open Access Journals (Sweden)

JA Mitchell

2009-06-01

Full Text Available Blood flow to the hindbrain, via the paired vertebral arteries, must be uncompromised for adequate neurological functioning of its vital centres. Therefore, it would seem unlikely that the intracranial vertebral artery would need to vasoconstrict, thus reducing its blood flow. In order to investigate the existence and location of a noradrenaline-mediated constrictor mechanism in the wall of the intracranial vertebral artery, transverse sections of ten baboon and ten monkey vessels were stained with sucrose-potassium phosphate-glyoxylic acid (counterstained with malachite-green. This method allows the visualisation of catecholaminergic nerves when the sections are exposed to ultraviolet light. In this study of primate vascular tissue, however, none of the monkey or baboon vertebral artery sections showed the presence of noradrenergic nerves in the tunica media – tunica adventitia junction or penetrating the tunica media of the arteries. These findings indicate that the intracranial vertebral artery does not have a neurogenic vasomotor function in primates.

Anomalous origin of the left coronary artery from the pulmonary artery with patent ductus arteriosus: a must to recognize entity.

Science.gov (United States)

Awasthy, Neeraj; Marwah, Ashutosh; Sharma, Rajesh; Dalvi, Bharat

2010-09-01

Anomalous left coronary artery from the pulmonary trunk (ALCAPA) presents in early infancy with a clinical picture of congestive heart failure with left ventricular (LV) dysfunction and mitral insufficiency. These manifestations of myocardial ischaemia may be masked in the presence of an associated patent ductus arteriosus (PDA) or ventricular septal defect (VSD) which prevents the fall of pulmonary artery pressures and allows perfusion of the anomalous coronary artery. We present a case of a patient with large PDA-associated ALCAPA and preserved LV function. The importance of such a finding lies in the fact that VSD closure or PDA ligation in such cases would unmask the ALCAPA.

Brachial artery protected by wrapped latissimus dorsi muscle flap in high voltage electrical injury

Science.gov (United States)

Gencel, E.; Eser, C.; Kokacya, O.; Kesiktas, E.; Yavuz, M.

2016-01-01

Summary High voltage electrical injury can disrupt the vascular system and lead to extremity amputations. It is important to protect main vessels from progressive burn necrosis in order to salvage a limb. The brachial artery should be totally isolated from the burned area by a muscle flap to prevent vessel disruption. In this study, we report the use of a wrap-around latissimus dorsi muscle flap to protect a skeletonized brachial artery in a high voltage electrical injury in order to salvage the upper extremity and restore function. The flap wrapped around the exposed brachial artery segment and luminal status of the artery was assessed using magnetic resonance angiography. No vascular intervention was required. The flap survived completely with good elbow function. Extremity amputation was not encountered. This method using a latissimus dorsi flap allows the surgeon to protect the main upper extremity artery and reconstruct arm defects, which contributes to restoring arm function in high voltage electrical injury. PMID:28149236

Common carotid artery thrombosis; Clinical and radiological evaluation

Energy Technology Data Exchange (ETDEWEB)

Ito, Yasuhiro; Yasuda, Takeshi; Hakusui, Shigetaka; Yanagi, Tsutomu (Nagoya Daini Red Cross Hospital (Japan)); Ito, Eiichi

1994-02-01

Common carotid artery thrombosis (CCAT) is not common. We studied 4 patients with CCAT to clarify the clinical and radiological features of this disorder. Case 1 had only episodes of TIA. Case 2 was diagnosed by chance as having CCAT at the time of admission due to cerebellar infarction. On the contrary, Cases 3 and 4 were admitted because of disturbance of consciousness and hemiparesis. Case 4 died soon after his stroke because of complications. We evaluated cases 1, 2 and 3 using head CT, head MRI, neck MRI, MR angiography, SPECT and cerebral angiography. Case 4, who was evaluated with head CT and cerebral angiography, was autopsied to confirm the occlusion of the common carotid artery. The clinical severity of CCAT varies from asymptomatic to severe, because each case differs in the time taken for complete occlusion of the common carotid artery; the development of collateral circulation; and hemodynamics of the brain. As for the collaterals their contribution is variable; for example, the thyrocervical and other arteries function as the bypass. We can diagnose CCAT easily and noninvasively using MR angiography and neck MRI based on disappearance of the flow void in the common carotid artery or internal carotid artery. On physical examination, it is important to detect faded pulsation of the superficial temporal artery that is ipsilateral to the occluded common carotid artery. (author).

Femoral Artery Atherosclerosis Is Associated With Physical Function Across the Spectrum of the Ankle-Brachial Index: The San Diego Population Study.

Science.gov (United States)

Wassel, Christina L; Ellis, Alicia M; Suder, Natalie C; Barinas-Mitchell, Emma; Rifkin, Dena E; Forbang, Nketi I; Denenberg, Julie O; Marasco, Antoinette M; McQuaide, Belinda J; Jenny, Nancy S; Allison, Matthew A; Ix, Joachim H; Criqui, Michael H

2017-07-20

The ankle-brachial index (ABI) is inadequate to detect early-stage atherosclerotic disease, when interventions to prevent functional decline may be the most effective. We determined associations of femoral artery atherosclerosis with physical functioning, across the spectrum of the ABI, and within the normal ABI range. In 2007-2011, 1103 multiethnic men and women participated in the San Diego Population Study, and completed all components of the summary performance score. Using Doppler ultrasound, superficial and common femoral intima media thickness and plaques were ascertained. Logistic regression was used to assess associations of femoral atherosclerosis with the summary performance score and its individual components. Models were adjusted for demographics, lifestyle factors, comorbidities, lipids, and kidney function. In adjusted models, among participants with a normal-range ABI (1.00-1.30), the highest tertile of superficial intima media thickness was associated with lower odds of a perfect summary performance score of 12 (odds ratio=0.56 [0.36, 0.87], P =0.009), and lower odds of a 4-m walk score of 4 (0.34 [0.16, 0.73], P =0.006) and chair rise score of 4 (0.56 [0.34, 0.94], P =0.03). Plaque presence (0.53 [0.29, 0.99], P =0.04) and greater total plaque burden (0.61 [0.43, 0.87], P =0.006) were associated with worse 4-m walk performance in the normal-range ABI group. Higher superficial intima media thickness was associated with lower summary performance score in all individuals ( P =0.02). Findings suggest that use of femoral artery atherosclerosis measures may be effective in individuals with a normal-range ABI, especially, for example, those with diabetes mellitus or a family history of peripheral artery disease, when detection can lead to earlier intervention to prevent functional declines and improve quality of life. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Spontaneous baroreflex sensitivity: toward an ideal index of cardiovascular risk in hypertension?

Science.gov (United States)

Lantelme, Pierre; Khettab, Fouad; Custaud, Marc-Antoine; Rial, Marie-Odile; Joanny, Christiane; Gharib, Claude; Milon, Hugues

2002-05-01

Estimating the risk entailed by classical risk factors like blood pressure (BP) or serum cholesterol may be difficult because of their variability and the often unknown duration of exposure. Having variables integrating the impact of those classical risk factors on the cardiovascular system would probably aid the prediction of cardiovascular events. The present study aimed at determining whether cardiac baroreflex sensitivity (BRS), correlates with several risk factors and thus is a good candidate for being such an integrative variable. As a comparison, left ventricular mass (LVM), pulse wave velocity (PWV), and creatinine were also tested for association with risk factors. A total of 302 subjects referred for hypertension, were considered. They had a 24-h BP recording and a determination of BRS by two different methods (sequence and alpha coefficient), in two different positions (lying and standing). They were also tested for the presence of left ventricular hypertrophy (LVH) (by echocardiography and electrocardiogram) and had a PWV measurement. Biological testing included serum lipids, blood glucose, creatinine, proteinuria and urinary excretion of microalbumin. There was a strong correlation between the two methods of BRS measurement in each position (P < 0.001). BRS determined by the sequence method in the lying position was correlated significantly and independently with age, 24-h systolic BP, heart rate, and serum cholesterol with P values < 0.001, < 0.001, < 0.01, and < 0.05, respectively. In an univariate analysis, BRS was also correlated with echocardiographic LVM index (r = -0.21, P < 0.05) and PWV (r = -0.27, P < 0.001), which possibly reflects its dependence on both vascular and cardiac damages. The present study supports the hypothesis that BRS could encompass the impact over time of several risk factors on the cardiovascular system. Thus, it may constitute a valuable parameter in assessing more precisely the risk of cardiovascular events.

Three-dimensional whole-brain perfusion quantification using pseudo-continuous arterial spin labeling MRI at multiple post-labeling delays: accounting for both arterial transit time and impulse response function.

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Qin, Qin; Huang, Alan J; Hua, Jun; Desmond, John E; Stevens, Robert D; van Zijl, Peter C M

2014-02-01

Measurement of the cerebral blood flow (CBF) with whole-brain coverage is challenging in terms of both acquisition and quantitative analysis. In order to fit arterial spin labeling-based perfusion kinetic curves, an empirical three-parameter model which characterizes the effective impulse response function (IRF) is introduced, which allows the determination of CBF, the arterial transit time (ATT) and T(1,eff). The accuracy and precision of the proposed model were compared with those of more complicated models with four or five parameters through Monte Carlo simulations. Pseudo-continuous arterial spin labeling images were acquired on a clinical 3-T scanner in 10 normal volunteers using a three-dimensional multi-shot gradient and spin echo scheme at multiple post-labeling delays to sample the kinetic curves. Voxel-wise fitting was performed using the three-parameter model and other models that contain two, four or five unknown parameters. For the two-parameter model, T(1,eff) values close to tissue and blood were assumed separately. Standard statistical analysis was conducted to compare these fitting models in various brain regions. The fitted results indicated that: (i) the estimated CBF values using the two-parameter model show appreciable dependence on the assumed T(1,eff) values; (ii) the proposed three-parameter model achieves the optimal balance between the goodness of fit and model complexity when compared among the models with explicit IRF fitting; (iii) both the two-parameter model using fixed blood T1 values for T(1,eff) and the three-parameter model provide reasonable fitting results. Using the proposed three-parameter model, the estimated CBF (46 ± 14 mL/100 g/min) and ATT (1.4 ± 0.3 s) values averaged from different brain regions are close to the literature reports; the estimated T(1,eff) values (1.9 ± 0.4 s) are higher than the tissue T1 values, possibly reflecting a contribution from the microvascular arterial blood compartment

Effect of Voluntary Ethanol Consumption Combined with Testosterone Treatment on Cardiovascular Function in Rats: Influence of Exercise Training.

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Sheila A Engi

Full Text Available This study evaluated the effects of voluntary ethanol consumption combined with testosterone treatment on cardiovascular function in rats. Moreover, we investigated the influence of exercise training on these effects. To this end, male rats were submitted to low-intensity training on a treadmill or kept sedentary while concurrently being treated with ethanol for 6 weeks. For voluntary ethanol intake, rats were given access to two bottles, one containing ethanol and other containing water, three 24-hour sessions per week. In the last two weeks (weeks 5 and 6, animals underwent testosterone treatment concurrently with exercise training and exposure to ethanol. Ethanol consumption was not affected by either testosterone treatment or exercise training. Also, drug treatments did not influence the treadmill performance improvement evoked by training. However, testosterone alone, but not in combination with ethanol, reduced resting heart rate. Moreover, combined treatment with testosterone and ethanol reduced the pressor response to the selective α1-adrenoceptor agonist phenylephrine. Treatment with either testosterone or ethanol alone also affected baroreflex activity and enhanced depressor response to acetylcholine, but these effects were inhibited when drugs were coadministrated. Exercise training restored most cardiovascular effects evoked by drug treatments. Furthermore, both drugs administrated alone increased pressor response to phenylephrine in trained animals. Also, drug treatments inhibited the beneficial effects of training on baroreflex function. In conclusion, the present results suggest a potential interaction between toxic effects of testosterone and ethanol on cardiovascular function. Data also indicate that exercise training is an important factor influencing the effects of these substances.

Role of ionotropic GABA, glutamate and glycine receptors in the tonic and reflex control of cardiac vagal outflow in the rat

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Goodchild Ann K

2010-10-01

Full Text Available Abstract Background Cardiac vagal preganglionic neurons (CVPN are responsible for the tonic, reflex and respiratory modulation of heart rate (HR. Although CVPN receive GABAergic and glutamatergic inputs, likely involved in respiratory and reflex modulation of HR respectively, little else is known regarding the functions controlled by ionotropic inputs. Activation of g-protein coupled receptors (GPCR alters these inputs, but the functional consequence is largely unknown. The present study aimed to delineate how ionotropic GABAergic, glycinergic and glutamatergic inputs contribute to the tonic and reflex control of HR and in particular determine which receptor subtypes were involved. Furthermore, we wished to establish how activation of the 5-HT1A GPCR affects tonic and reflex control of HR and what ionotropic interactions this might involve. Results Microinjection of the GABAA antagonist picrotoxin into CVPN decreased HR but did not affect baroreflex bradycardia. The glycine antagonist strychnine did not alter HR or baroreflex bradycardia. Combined microinjection of the NMDA antagonist, MK801, and AMPA antagonist, CNQX, into CVPN evoked a small bradycardia and abolished baroreflex bradycardia. MK801 attenuated whereas CNQX abolished baroreceptor bradycardia. Control intravenous injections of the 5-HT1A agonist 8-OH-DPAT evoked a small bradycardia and potentiated baroreflex bradycardia. These effects were still observed following microinjection of picrotoxin but not strychnine into CVPN. Conclusions We conclude that activation of GABAA receptors set the level of HR whereas AMPA to a greater extent than NMDA receptors elicit baroreflex changes in HR. Furthermore, activation of 5-HT1A receptors evokes bradycardia and enhances baroreflex changes in HR due to interactions with glycinergic neurons involving strychnine receptors. This study provides reference for future studies investigating how diseases alter neurochemical inputs to CVPN.

Determination of the arterial input function in mouse-models using clinical MRI

International Nuclear Information System (INIS)

Theis, D.; Fachhochschule Giessen-Friedberg; Keil, B.; Heverhagen, J.T.; Klose, K.J.; Behe, M.; Fiebich, M.

2008-01-01

Dynamic contrast enhanced magnetic resonance imaging is a promising method for quantitative analysis of tumor perfusion and is increasingly used in study of cancer in small animal models. In those studies the determination of the arterial input function (AIF) of the target tissue can be the first step. Series of short-axis images of the heart were acquired during administration of a bolus of Gd-DTPA using saturation-recovery gradient echo pulse sequences. The AIF was determined from the changes of the signal intensity in the left ventricle. The native T1 relaxation times and AIF were determined for 11 mice. An average value of (1.16 ± 0.09) s for the native T1 relaxation time was measured. However, the AIF showed significant inter animal variability, as previously observed by other authors. The inter-animal variability shows, that a direct measurement of the AIF is reasonable to avoid significant errors. The proposed method for determination of the AIF proved to be reliable. (orig.)