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Sample records for arterial pressure-volume relationship

  1. The pressure-volume relationship of the heart: past, present and future.

    PubMed

    Sunagawa, Kenji

    2010-01-01

    The pressure-volume relationship of the heart was first reported more than a century ago. It was not widely accepted, however, until the mid-1970s. The pressure-volume diagram became a central theme of cardiac mechanics once it was shown to be a good representation of ventricular mechanics. Early in 1980s, the introduction of the ventricular interaction with afterload using effective arterial elastance made it possible to translate ventricular mechanical properties represented by the pressure-volume relationship to the pumping ability of the heart. Furthermore incorporating the framework of ventricular arterial interaction into the classic Guyton's circulatory equilibrium early in 2000s enabled us to express quantitatively how mechanical properties of the ventricles and vascular systems determine the circulatory equilibrium. Successful quantitative descriptions of circulatory equilibrium using the pressure-volume concept would promote basic cardiovascular physiology and accelerate its clinical applications.

  2. Nonlinear lymphangion pressure-volume relationship minimizes edema

    PubMed Central

    Venugopal, Arun M.; Stewart, Randolph H.; Laine, Glen A.

    2010-01-01

    Lymphangions, the segments of lymphatic vessel between two valves, contract cyclically and actively pump, analogous to cardiac ventricles. Besides having a discernable systole and diastole, lymphangions have a relatively linear end-systolic pressure-volume relationship (with slope Emax) and a nonlinear end-diastolic pressure-volume relationship (with slope Emin). To counter increased microvascular filtration (causing increased lymphatic inlet pressure), lymphangions must respond to modest increases in transmural pressure by increasing pumping. To counter venous hypertension (causing increased lymphatic inlet and outlet pressures), lymphangions must respond to potentially large increases in transmural pressure by maintaining lymph flow. We therefore hypothesized that the nonlinear lymphangion pressure-volume relationship allows transition from a transmural pressure-dependent stroke volume to a transmural pressure-independent stroke volume as transmural pressure increases. To test this hypothesis, we applied a mathematical model based on the time-varying elastance concept typically applied to ventricles (the ratio of pressure to volume cycles periodically from a minimum, Emin, to a maximum, Emax). This model predicted that lymphangions increase stroke volume and stroke work with transmural pressure if Emin < Emax at low transmural pressures, but maintain stroke volume and stroke work if Emin= Emax at higher transmural pressures. Furthermore, at higher transmural pressures, stroke work is evenly distributed among a chain of lymphangions. Model predictions were tested by comparison to previously reported data. Model predictions were consistent with reported lymphangion properties and pressure-flow relationships of entire lymphatic systems. The nonlinear lymphangion pressure-volume relationship therefore minimizes edema resulting from both increased microvascular filtration and venous hypertension. PMID:20601461

  3. Pressure-volume Relationship in the Stress-echocardiography Laboratory: Does (Left Ventricular End-diastolic) Size Matter?

    PubMed

    Bombardini, Tonino; Mulieri, Louis A; Salvadori, Stefano; Costantino, Marco Fabio; Scali, Maria Chiara; Marzilli, Mario; Picano, Eugenio

    2017-02-01

    The variation between rest and peak stress end-systolic pressure-volume relation is an afterload-independent index of left ventricular contractility. Whether and to what extent it depends on end-diastolic volume remains unclear. The aim of this study was to assess the dependence of the delta rest-stress end-systolic pressure-volume relation on end-diastolic volume in patients with negative stress echo and all ranges of resting left ventricular function. We analyzed interpretable data obtained in 891 patients (593 men, age 63 ± 12 years) with ejection fraction 47% ± 12%: 338 were normal or near-normal or hypertensive; 229 patients had coronary artery disease; and 324 patients had ischemic or nonischemic dilated cardiomyopathy. They were studied with exercise (n = 172), dipyridamole (n = 482) or dobutamine (n = 237) stress echocardiography. The end-systolic pressure-volume relation was evaluated at rest and peak stress from raw measurement of systolic arterial pressure by cuff sphygmomanometer and end-systolic volume by biplane Simpson rule 2-dimensional echocardiography. Absolute values of delta rest-stress end-systolic pressure-volume relation were higher for exercise and dobutamine than for dipyridamole. In the overall population, an inverse relationship between end-systolic pressure-volume relation and end-diastolic volume was present at rest (r(2) = 0.69, P < .001) and peak stress (r(2) = 0.56, P < .001), but was absent if the delta rest-stress end-systolic pressure-volume relation was considered (r(2) = 0.13). Left ventricular end-diastolic volume does not affect the rest-stress changes in end-systolic pressure-volume relation in either normal or abnormal left ventricles during physical or pharmacological stress. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  4. Association of Arterial Pressure Volume Index With the Presence of Significantly Stenosed Coronary Vessels

    PubMed Central

    Ueda, Takashi; Miura, Shin-ichiro; Suematsu, Yasunori; Shiga, Yuhei; Kuwano, Takashi; Sugihara, Makoto; Ike, Amane; Iwata, Atsushi; Nishikawa, Hiroaki; Fujimi, Kanta; Saku, Keijiro

    2016-01-01

    Background A blood pressure (BP) monitoring system (PASESA®) can be used to easily analyze the characteristics of central and peripheral arteries during the measurement of brachial BP. Methods We enrolled 108 consecutive patients (M/F = 86/22, age 70 ± 10 years) who underwent coronary angiography (CAG) due to suspected coronary artery disease (CAD) in whom we could measure various parameters using PASESA® in addition to brachial-ankle pulse wave velocity (baPWV). The patients were divided into two groups: patients who did not have significantly stenosed coronary vessel disease (n = 33, non-SVD group) and those who had at least one significantly stenosed coronary vessel (n = 75, SVD group). The characteristics of central and peripheral arteries (arterial velocity pulse index (AVI) and arterial pressure volume index (API), respectively) and baPWV were measured. Estimated central BP (eCBP) was calculated from the data obtained from PASESA®, and CBP was also measured simultaneously by invasive catheterization. Results API, but not AVI and baPWV, in the SVD group was significantly higher than that in the non-SVD group. Although eCBP was significantly associated with CBP, there was no difference in eCBP between the groups. There were significant associations among API, AVI and baPWV, albeit these associations were relatively weak. A multivariate logistic regression revealed that API and β-blocker were significant independent variables that were associated with the presence of significant coronary stenosis. The cut-off level of API that gave the greatest sensitivity and specificity for the presence of SVD was 24 units (sensitivity 0.636 and specificity 0.667). Conclusion In conclusion, API, but not AVI or baPWV, is associated with the presence of significant coronary stenosis. PMID:27429681

  5. The relationship between the area of peripherally-derived pressure volume loops and systemic vascular resistance.

    PubMed

    Colquhoun, Douglas; Dunn, Lauren K; McMurry, Timothy; Thiele, Robert H

    2013-12-01

    Arterial and photoplethysmographic (PPG) waveforms have been utilized to non-invasively estimate stroke volume from the pulse contour. The ability of these pulse contour devices to accurately predict stroke volume is degraded when afterload changes significantly. There is a need for a non-invasive device capable of identifying when vascular tone has changed. Shelley et al. previously described a qualitative relationship between peripheral pressure volume (PV) loops (in which pressure waveforms from an intra-arterial catheter are combined with volume waveforms from the PPG waveform) and changes in vascular tone. The purpose of this study was to quantitatively compare changes in the area of peripheral PV loops with changes in systemic vascular resistance (SVR) in a patient population undergoing major surgery. Physiologic data from ten patients undergoing liver transplantation was extracted from a hemodynamic database. A peak detection algorithm was applied to both the arterial and PPG waveforms, which were manually aligned so that the troughs occurred at identical time points. PV loop area (PVA) for each heartbeat was calculated and median PVA was recorded for each minute. PVA for each patient was indexed to the average value for the first 5 min (because PPG amplitude has no standard and is not comparable between patients) and compared to indexed SVR at all points for which SVR was available. SVR and PVA were plotted as a function of time and outliers (3.1 %) removed. The Pearson correlation coefficient describing the relationship between PVAi and SVRi was 0.67 (1,728 min of data, p = 0.0020, sign test over 10 patients) and between MAP and SVR was 0.71. There was no meaningful correlation between ΔSVR and either ΔPVA or ΔMAP (based on minute-to-minute changes). Indexed values of PVA are correlated with indexed values of SVR and may serve as a useful monitor for changes in afterload but in their present form do not offer added value above the measurement of

  6. Pressure-volume relationships and elastance in the knee joint of the dog.

    PubMed Central

    Nade, S; Newbold, P J

    1984-01-01

    This study has investigated changes in intra-articular hydrostatic pressure in the knee joints of normal dogs in response to continuous and stepwise infusions of fluids. The relationship between pressure and volume in the joint was examined over the pressure range of -8 to +50 mmHg, and also at much higher pressures often associated with joint disease or injury. The effects of joint angle and dog weight on the pressure-volume relationship and on elastance of the dogs' knees were also examined. With liquid paraffin B.P. the pressure was found to increase more with each unit volume infused at subatmospheric pressures than at pressures around atmospheric, and increased more again at higher pressures. The pressure-volume curve with saline infusions was affected by egress of fluid from the joint at supra-atmospheric pressure. Above +5 mmHg the rise in pressure per unit volume infused was less than that for paraffin at the same volume. Elastance and compliance of the normal joint capsule were calculated from the pressure-volume data. Elastance was high at subatmospheric pressures, decreased rapidly as atmospheric pressure was approached and rose as a linear function of pressure above 12 mmHg. The biphasic shape of the elastance-pressure curve is discussed, and explanations for the shape are suggested. After intra-articular pressure in the knee was raised by infusion of paraffin oil the joint was moved through the range of positions from 125 deg extension to 50 deg flexion. Intra-articular pressure did not change across the range 125-110 deg. However, increasing the angle of flexion from 110 to 50 deg resulted in a rise in pressure which became steeper for each volume increment. Increasing intra-articular fluid volume caused a decrease in the total range of movement of the joint. The pressure-volume curves measured at extended angles of 110, 125 and 140 deg, where the starting pressures were subatmospheric, were the same. At flexed joint positions of 80 and 50 deg, where

  7. End-systolic pressure-volume relationship and intracellular control of contraction.

    PubMed

    Landesberg, A

    1996-01-01

    The left ventricular (LV) pressure-volume relationship and the effect of ejection on pressure generation are predicted theoretically based on the intracellular control mechanisms. The control of contraction is described based on coupling calcium kinetics and cross-bridge cycling. The analysis of published skinned and intact cardiac muscle data suggests two feedback control loops: 1) a positive cooperative mechanism that determines the force-length relationship, the length dependence calcium sensitivity of the contractile filaments, and the related Frank Starling law; and 2) a negative mechanical feedback that determines the force-velocity relationship and the generated power. The interplay between these two feedback mechanisms explains the wide spectrum of phenomena associated with the end-systolic pressure-volume relationship (ESPVR); it provides an explanation for the "shortening deactivation" and for the recent observations of the positive effect of ejection on the ESPVR, i.e., the increase of the end-systolic pressure of the ejecting beat over the pressure of the isovolumic beat at the same end-systolic volume. Furthermore, the analysis suggests that the LV contractility depends on the balance between the two intracellular mechanisms and that the effect of loading conditions is determined through these intracellular mechanisms.

  8. A novel system for continuous peripheral arterial pressure-volume loop measurement.

    PubMed

    Shyu, Liang-Yu; Tsai, Meng-Chieh; Yeih, Dong-Feng; Hu, Weichih

    2011-01-01

    This study develops a system to obtain continuous blood pressure signal and impedance plethysmography (IPG) signal, simultaneously. Based on the principle of impedance measurement, the peripheral vessel volume change can be computed from the IPG signal. Equipped with simultaneous information of pressure and volume, a pressure-volume (PV) loop can be constructed. It is well known that the left ventricular pressure-volume loop contains a number of feature points indicating the performance of cardiac function. Therefore, in this study, the same principle is used to try to discuss the peripheral vessel pressure-volume loop. Ten volunteers were recruited for this study. Subjects went through the cold pressor test by immersing their left foot into ice water. Blood pressure signal and impedance changed were recorded using a custom-made system. The results illustrated that the pressure-volume loop, as it was expected, demonstrated a contraction phenomenon after stimulation in five out of ten subjects. The areas of those pressure-volume loops reduced as much as 70% in some subject. However, loop responses to stressors varied from subject to subject and the slope of the loop did not alter significantly. In conclusion, the proposed system is a potential way to measure and to investigate the compliance and characteristic of peripheral blood vessel.

  9. Guidelines for inspiratory flow setting when measuring the pressure-volume relationship.

    PubMed

    Bensenor, Fábio E; Vieira, Joaquim E; Auler, Jose Otávio C

    2003-07-01

    Acquisition of pressure-volume (PV) curves to improve ventilation strategy is time consuming when using static methods. Low-flow techniques use less time, but compliance values can be decreased by the resistance to flow in airways and tracheal tube (P-t). In this study, we determined the impact of three flows on the resistive component of airway pressure during anesthesia. We studied 10 ASA status P1/P2 patients with normal respiratory function. Airway and esophageal pressures were measured while volume-control ventilated with 6, 12, and 30 L/min continuous flows. PV curves, lower inflection point, respiratory system, and chest wall compliances at 250, 500, 750, and 1000 mL tidal volume were established before and after removing P-t. Data were submitted to analysis of variance. The inflection point was lower for the lower flow when comparing 6 and 12 with 30 L/min (P < 0.001). No difference was found between 6 and 12 L/min. Removal of P-t showed a difference only for 30 L/min (P = 0.004). Higher flows generated lower compliances. P-t subtraction reduced compliances only for 30 L/min. Chest wall compliances showed no difference between flows. We concluded that flows < or =12 L/min minimize P-t during intraoperative PV curves acquisition. Compliances suggest 6 L/min as the most adequate flow. We suggest guidelines for inspiratory flow setting when measuring the pressure-volume relationship during anesthesia based on the comparison among three different continuous flow values, aiming at better intraoperative respiratory settings in patients with normal respiratory function.

  10. The pressure/volume relationship during dobutamine stress echocardiography in transplanted heart: comparison with quality of life and coronary anatomy

    PubMed Central

    2012-01-01

    Background Cardiac allograft vasculopathy (CAV) is a major late complication in cardiac transplant recipients and has a relevant impact on outcome of these patients. Aims of this study: to compare, in cardiac transplant recipients patients, the diagnostic value of pressure/volume relationship (ESPVR) during dobutamine stress echocardiography (DSE) for coronary artery disease, assessed by Multislice Computed Tomography (MSCT), and by coronary angiography (CA). We also analyzed any possible relationship between ESPVR and the Health Related Quality of Life of the patients (HRQoL), evaluated by SF–36 questionnaire. Methods 25 consecutive patients underwent DSE within 24 hours after MSCT coronary angiogram and then they underwent CA. The HRQoL questionnaire was administered to the patients in the settings of DSE. They were followed-up for 6 months. Results DSE has a sensitivity in detecting CAV of 67%, specificity of 95%, positive predictive value of 67% and negative predictive value of 95%; DSE with ESPVR has a sensitivity of 100%, specificity of 95%, positive predictive value of 75%, negative predictive value of 100%; MSCT has a sensitivity of 100%; specificity of 82%; positive predictive value of 43%; negative predictive value of 100%. Htx recipients with a flat-biphasic ESPVR, although asymptomatic, perceived a worst HRQoL compared with the up-sloping ESPVR population, and this is statistically significant for the general health (p 0.0004), the vitality (p 0.0013) and the mental health (p 0.021) SF-36 subscale. Conclusions Evaluation with DSE and ESPVR is accurate in the clinical control of heart transplant recipients reserving invasive evaluation only for patients with abnormal contractility indexes. PMID:23150924

  11. The pressure/volume relationship during dobutamine stress echocardiography in transplanted heart: comparison with quality of life and coronary anatomy.

    PubMed

    Minardi, Giovanni; Zampi, Giordano; Pergolini, Amedeo; Pulignano, Giovanni; Scappaticci, Massimiliano; Orsini, Francesca Moschella; Pero, Gaetano; Monica, Paola Lilla Della; Cioffi, Giovanni; Musumeci, Francesco

    2012-11-14

    Cardiac allograft vasculopathy (CAV) is a major late complication in cardiac transplant recipients and has a relevant impact on outcome of these patients. to compare, in cardiac transplant recipients patients, the diagnostic value of pressure/volume relationship (ESPVR) during dobutamine stress echocardiography (DSE) for coronary artery disease, assessed by Multislice Computed Tomography (MSCT), and by coronary angiography (CA). We also analyzed any possible relationship between ESPVR and the Health Related Quality of Life of the patients (HRQoL), evaluated by SF-36 questionnaire. 25 consecutive patients underwent DSE within 24 hours after MSCT coronary angiogram and then they underwent CA. The HRQoL questionnaire was administered to the patients in the settings of DSE. They were followed-up for 6 months. DSE has a sensitivity in detecting CAV of 67%, specificity of 95%, positive predictive value of 67% and negative predictive value of 95%; DSE with ESPVR has a sensitivity of 100%, specificity of 95%, positive predictive value of 75%, negative predictive value of 100%; MSCT has a sensitivity of 100%; specificity of 82%; positive predictive value of 43%; negative predictive value of 100%. Htx recipients with a flat-biphasic ESPVR, although asymptomatic, perceived a worst HRQoL compared with the up-sloping ESPVR population, and this is statistically significant for the general health (p 0.0004), the vitality (p 0.0013) and the mental health (p 0.021) SF-36 subscale. Evaluation with DSE and ESPVR is accurate in the clinical control of heart transplant recipients reserving invasive evaluation only for patients with abnormal contractility indexes.

  12. Comparative assessment of right ventricular performance from the pressure-volume relationship in double-muscled and conventional calves.

    PubMed Central

    Amory, H; McEntee, K; Linden, A S; Desmecht, D J; Beduin, J M; D'Orio, V; Lekeux, P M

    1995-01-01

    Forty-one and 55 records of right-sided and systemic arterial pressures, cardiac output, and end-diastolic and end-systolic right ventricular volumes were collected from a group of 6 conventional and 6 double-muscled calves, respectively. In each group, the mean right ventricular pressure-volume loop was constructed. Global cardiac performance was significantly lower in the double-muscled than in the conventional calves. The right ventricular end-diastolic and end-systolic volumes, as well as the diastolic portion of the mean pressure-volume loop, were similar in the 2 groups. Those results suggest that the reduced cardiac performance of double-muscled calves is not due to a lowered ventricular preload and that diastolic properties of their myocardium are similar to those of conventional calves. When expressed on a body weight basis, however, the right ventricular end-diastolic and end-systolic volumes were lower in the double-muscled than in conventional calves. When expressed as a function of probable metabolic demand, therefore, the volumetric capacity of the cardiac pump appears to be reduced in double-muscled calves. The significantly lower right ventricular ejection fraction, maximal rate of ventricular pressure rise and right ventricular peak-systolic pressure to end-systolic volume ratio measured in double-muscled as compared with conventional calves suggest that reduced myocardial contractility may also be partly responsible for the significantly lower stroke index of the former calves. The cardiac pump of double-muscled cattle thus seems to be less effective than that of conventional cattle because of reduced volumetric capacity and lowered strength of contraction. PMID:7648526

  13. A Simple Mercury-Free Laboratory Apparatus to Study the Relationship between Pressure, Volume, and Temperature in a Gas

    ERIC Educational Resources Information Center

    McGregor, Donna; Sweeney, William V.; Mills, Pamela

    2012-01-01

    A simple and inexpensive mercury-free apparatus to measure the change in volume of a gas as a function of pressure at different temperatures is described. The apparatus is simpler than many found in the literature and can be used to study variations in pressure, volume, and temperature. (Contains 1 table and 7 figures.)

  14. A Simple Mercury-Free Laboratory Apparatus to Study the Relationship between Pressure, Volume, and Temperature in a Gas

    ERIC Educational Resources Information Center

    McGregor, Donna; Sweeney, William V.; Mills, Pamela

    2012-01-01

    A simple and inexpensive mercury-free apparatus to measure the change in volume of a gas as a function of pressure at different temperatures is described. The apparatus is simpler than many found in the literature and can be used to study variations in pressure, volume, and temperature. (Contains 1 table and 7 figures.)

  15. A multi-scale cardiovascular system model can account for the load-dependence of the end-systolic pressure-volume relationship

    PubMed Central

    2013-01-01

    Background The end-systolic pressure-volume relationship is often considered as a load-independent property of the heart and, for this reason, is widely used as an index of ventricular contractility. However, many criticisms have been expressed against this index and the underlying time-varying elastance theory: first, it does not consider the phenomena underlying contraction and second, the end-systolic pressure volume relationship has been experimentally shown to be load-dependent. Methods In place of the time-varying elastance theory, a microscopic model of sarcomere contraction is used to infer the pressure generated by the contraction of the left ventricle, considered as a spherical assembling of sarcomere units. The left ventricle model is inserted into a closed-loop model of the cardiovascular system. Finally, parameters of the modified cardiovascular system model are identified to reproduce the hemodynamics of a normal dog. Results Experiments that have proven the limitations of the time-varying elastance theory are reproduced with our model: (1) preload reductions, (2) afterload increases, (3) the same experiments with increased ventricular contractility, (4) isovolumic contractions and (5) flow-clamps. All experiments simulated with the model generate different end-systolic pressure-volume relationships, showing that this relationship is actually load-dependent. Furthermore, we show that the results of our simulations are in good agreement with experiments. Conclusions We implemented a multi-scale model of the cardiovascular system, in which ventricular contraction is described by a detailed sarcomere model. Using this model, we successfully reproduced a number of experiments that have shown the failing points of the time-varying elastance theory. In particular, the developed multi-scale model of the cardiovascular system can capture the load-dependence of the end-systolic pressure-volume relationship. PMID:23363818

  16. The Use of Elasto-Visco-Plastic Material Model Coupled with Pressure-Volume Thermodynamic Relationship to Simulate the Stretch Blow Molding of Polyethylene Terephthalate

    NASA Astrophysics Data System (ADS)

    Mir, H.; Benrabah, Z.; Thibault, F.

    2007-05-01

    The use of polyethylene terephthalate (PET) in the stretch blow molding process presents several challenging issues due to various processing parameters and complex behavior of the material, which is both temperature and strain-rate dependent. In this paper, we generalize the G'Sell-Jonas law in 3D to model and simulate the elasto-visco-plastic (EVP) behavior of PET, taking into account strain-hardening and strain-softening. It is observed that the internal pressure (inside the preform) is significantly different from the nominal pressure (imposed in the blowing device upstream) since the internal pressure and the enclosed volume of the preform are fully coupled. In order to accurately simulate this phenomenon, a thermodynamic model was used to characterize the pressure-volume relationship (PVR). The predicted pressure evolution is thus more realistic when imposing only the machine power of the blowing device (air compressor or vacuum pump). Mechanical and temperature equilibrium equations are fully nonlinear and solved separately with implicit schemes on the current deformed configuration, which is updated at each time step. Biaxial characterization tests were used to determine the model parameters in order to simulate the stretch blow molding process using the pressure-volume thermodynamic relationship. To validate this model, thickness predictions for three industrial cases will be presented and compared to experimental measurements.

  17. Effects of sodium nitroprusside on left ventricular diastolic pressure-volume relations.

    PubMed Central

    Brodie, B R; Grossman, W; Mann, T; McLaurin, L P

    1977-01-01

    The effect of sodium nitroprusside on the relationship between left ventricular pressure and volume during diastole was studied in 11 patients with congestive heart failure. Nitroprusside was infused to lower mean arterial pressure approximately 20-30 mm Hg. High fidelity left ventricular pressures were recorded in all patients simultaneously with left ventricular cineangiography (biplane in eight and single plane in three patients), allowing precise measurement of pressure and volume throughout the cardiac cycle. Left ventricular diastolic pressure-volume curves were constructed in each patient from data obtained before and during nitroprusside infusion. In 9 of 11 patients there was a substantial downward displacement of the diastolic pressure-volume curve during nitroprusside infusion, with left ventricular pressure being lower for any given volume with nitroprusside. Serial left ventricular cineangiograms performed 15 min apart in six additional subjects who did not receive sodium nitroprusside showed no shift in the diastolic pressure-volume relation, indicating that the shift seen with nitroprusside was not due to the angiographic procedure itself. A possible explanation for the altered diastolic pressure-volume relationships with nitroprusside might be a direct relaxant effect of nitroprusside on ventricular muscle, similar to its known relaxant effect on vascular smooth muscle. Alternatively, nitroprusside may affect the diastolic pressure-volume curve by affecting viscous properties or by altering one or more of the extrinsic constraints acting upon the left ventricle. PMID:830666

  18. Left ventricular pressure-volume relationships during normal growth and development in the adult rat--studies in 8- and 50-week-old male Wistar rats.

    PubMed

    Bal, M P; de Vries, W B; van der Leij, F R; van Oosterhout, M F M; Baan, J; van der Wall, E E; van Bel, F; Steendijk, P

    2005-11-01

    Left ventricular (LV) pressure-volume relations provide relatively load-independent indexes of systolic and diastolic LV function, but few data are available on pressure-volume relations during growth and development in the normal adult heart. Furthermore, to quantify intrinsic ventricular function the indexes should be normalized for heart weight. However, in many studies the indexes are reported in absolute terms, or body weight-correction is used as a surrogate for heart weight-correction. We determined pressure-volume relations in young (8-week-old, n = 13) and middle-aged (50-week-old, n = 19) male Wistar rats in relation to their heart and body weights. The animals were anaesthetized and a 2F pressure-conductance catheter was introduced into the LV to measure pressure-volume relations. Heart and body weights were significantly higher in the 50-week-old rats, whereas the heart-to-body weight ratio was significantly lower (2.74 +/- 0.32 vs. 4.41 +/- 0.37 mg g(-1), P < 0.001). Intrinsic systolic function, quantified by the slopes of the end-systolic pressure-volume relation (E(ES)), the dP/dt(MAX) vs. end-diastolic volume relation (S-dP), and the preload recruitable stroke work relation (PRSW), normalized for heart weight, was slightly decreased in the 50-week-old rats (S-dP: -6%, P < 0.004; PRSW: -3%, P < 0.06). Heart weight-corrected diastolic indexes were not significant different. The absolute indexes qualitatively showed the same results, but body-weight corrected pressure-volume indexes showed improved systolic function and significantly depressed diastolic function. Intrinsic systolic function slightly decreases from the juvenile to the middle-aged period in normal male Wistar rats. Furthermore, correction of pressure-volume indexes for body weight is not an adequate surrogate for heart weight-correction in these animals.

  19. Effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 on the left ventricular pressure-volume relationship in the halothane-anesthetized dogs.

    PubMed

    Honda, Atsushi; Nakamura, Yuji; Ohara, Hiroshi; Cao, Xin; Nomura, Hiroaki; Katagi, Jun; Wada, Takeshi; Izumi-Nakaseko, Hiroko; Ando, Kentaro; Sugiyama, Atsushi

    2016-03-15

    Cardiac effects of a prostagrandin EP4-receptor agonist ONO-AE1-329 were assessed in the halothane-anesthetized dogs under the monitoring of left ventricular pressure-volume relationship, which were compared with those of clinically recommended doses of dopamine, dobutamine and milrinone (n=4-5 for each treatment). ONO-AE1-329 was intravenously administered in doses of 0.3, 1 and 3 ng/kg/min for 10 min with a pause of 20 min. Dopamine in a dose of 3 µg/kg/min for 10 min, dobutamine in a dose of 1 µg/kg/min for 10 min and milrinone in a dose of 5 µg/kg/min for 10 min followed by 0.5 µg/kg/min for 10 min were intravenously administered. Low dose of ONO-AE1-329 increased the stroke volume. Middle dose of ONO-AE1-329 increased the cardiac output, left ventricular end-diastolic volume, ejection fraction, maximum upstroke/downstroke velocities of the left ventricular pressure and external work, but decreased the end-systolic pressure and internal work besides the change by the low dose. High dose of ONO-AE1-329 increased the heart rate and maximum elastance, but decreased the end-systolic volume besides the changes by the middle dose. Dopamine, dobutamine and milrinone exerted essentially similar cardiac effects to ONO-AE1-329, but they did not significantly change the end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, end-systolic pressure, maximum elastance, external work or internal work. Thus, EP4-receptor stimulation by ONO-AE1-329 may have potential to better promote the passive ventricular filling than the conventional cardiotonic drugs, which could become a candidate of novel therapeutic strategy for the treatment of heart failure with preserved ejection fraction. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Posterior lymph heart function in two species of anurans: analysis based on both in vivo pressure-volume relationships by conductance manometry and ultrasound.

    PubMed

    Crossley, Dane A; Hillman, Stanley S

    2010-11-01

    Rhinella marina and Lithobates catesbeianus have known differences in the capacity to mobilize lymph to stabilize blood volume following dehydration and hemorrhage. The purpose of these experiments was to assess whether there are interspecific differences in basic lymph heart functions. The end diastolic volumes of posterior lymph hearts averaged 10.8 μl kg⁻¹ in R. marina and 7.9-10.8 μl kg⁻¹ in L. catesbeianus by conductance manometry, and 9-32 μl kg⁻¹ in R. marina by ultrasound techniques, which correlated with body mass. Stroke volumes were approximately 20% of end diastolic volumes in both species. Peak systolic pressures and stroke work were correlated with the index of contractility (dP/dt(max)) in both species. Stroke volume was correlated to stroke work but not peak systolic pressure, end diastolic volume or end diastolic pressure indicating the preload variables do not seem to determine stroke volume as would be predicted from Starling considerations of the blood heart. Renal portal elastance (end systolic pressure/stroke volume) an afterload index did not differ interspecifically, and was equivalent to values for systemic flow indices from mice of equivalent ventricular volume. These data, taken together with predictions derived from mammalian models on the effect of high resistance indicate afterload (renal portal pressure), may be important determinants of posterior lymph heart stroke volume. The shape of the pressure-volume loop is different from an idealized version previously reported, and is influenced by end diastolic volume. Our data indicate that increasing end diastolic pressure and volume can influence the loop shape but not the stroke volume. This indicates that lymph hearts do not behave in a Starling Law manner with increased preload volume.

  1. [Coronary disease. II. Analysis of diastolic pressure-volume correlations and left ventricular elasticity in 110 patients].

    PubMed

    Strauer, B E; Bolte, H D; Heimburg, P; Riecker, G

    1975-04-01

    Left ventricular pressure-volume relationships as well as diastolic compliance were determined in 110 patients with coronary heart disease during routine right and left heart catheterization, coronary angiography and ventriculography. 1. Enddiastolic and endystolic volume of the left ventricle were increased in severe coronary heart disease dependent on the degree of coronary stenosis; left ventricular ejection fraction was consecutively reduced. 2. Left ventricular enddiastolic pressure, diastolic pressure difference and diastolic rate of pressure rise were increased in corrleation with coronary artery stenosis. In contrast, last diastolic volume inflow into the left ventricle was nearly the same in all groups. Left ventricular stiffness, expressed as dP/dV, was significantly increased dependent on the severity degree of coronary artery disease. 3. Diastolic pressure-volume relationships revealed greater steepness in coronary artery disease, significantly dependent, on the corresponding severity degree. 4. Hemodynamic measures (stroke volume, cardiac index, ejection fraction) were decreased parallel to the increased left ventricular wall stiffness. The results demonstrated decreased left ventricular compliance in coronary heart disease. There was a striking correlation between the severity degree of coronary heart disease and the decrease of left ventricular compliance. Validity and limitations of the techniques of estimating left ventricular compliance from diastolic pressures and volumes as well as the effects of a decrease of left ventricular compliance on cardiac mechanics are discussed.

  2. Pressure volume analysis in the mouse

    PubMed Central

    Townsend, DeWayne

    2017-01-01

    SHORT ABSTRACT This manuscript describes a detailed protocol for the collection of pressure-volume data from the mouse. LONG ABSTRACT Understanding the causes and progression of heart disease presents a significant challenge to the biomedical community. The genetic flexibility of the mouse provides great potential to explore cardiac function at the molecular level. The mouse’s small size does present some challenges in regards to performing detailed cardiac phenotyping. Miniaturization and other advancements in technology have made many methods of cardiac assessment possible in the mouse. Of these, the simultaneous collection of pressure and volume data provides a detailed picture of cardiac function that is not available through any other modality. Here a detailed procedure for the collection of pressure-volume loop data is described. Included is a discussion of the principles underlying the measurements and the potential sources of error. Anesthetic management and surgical approaches are discussed in great detail as they are both critical to obtaining high quality hemodynamic measurements from the mouse. The principles of hemodynamic protocol development and relevant aspects of data analysis are also addressed. PMID:27166576

  3. Relationship of the angiographic extent of peripheral arterial disease with coronary artery involvement.

    PubMed

    Satiroglu, Omer; Kocaman, Sinan Altan; Karadag, Zakir; Temiz, Ahmet; Cetin, Mustafa; Canga, Aytun; Erdogan, Turan; Bostan, Mehmet; Cicek, Yuksel; Durakoglugil, Emre; Vural, Mutlu; Bozkurt, Engin

    2012-07-01

    To determine the co-incidence of coronary artery disease (CAD) in patients investigated for peripheral arterial disease (PAD), and to establish the relationship between the risk factors in the two groups of patients. The prospective study, done from January 2005 and April 2009, at the Cardiology Clinic of Rize Education and Research Hospital, Rize and John F. Kennedy Hospital, Istanbul, Turkey, had a cohort of 307 patients who had been diagnosed with peripheral artery disease either clinically or by ultrasonography for the arteries of the lower extremities and had undergone coronary angiography and peripheral angiography in the same or different sessions. The patients were evaluated in terms of age, gender and atherosclerotic risk factors. Relationship of the extent of peripheral arterial disease with coronary artery involvement was investigated. Of the 307 patients, 251 (81.8%) were male, and the mean age was 62.1 +/- 9.5 years. In the study population, 178 (58.0%) patients were diagnosed as hypertensive, 84 (27.4%) patients were diabetic, 18 (5.9%) patients had a family history of coronary artery disease, 111 (36.2%) were smokers, 149 (48.5%) were hypercholesterolemic, and 20 (6.5%) had cerebrovascular/carotid disease. In 92.3% of patients with peripheral arterial disease, various levels of coronary stenosis (P = 0.007) was noticed. Hypertension was a risk factor for both coronary and peripheral artery diseases (p = 0.012 and 0.027, respectively). Univariate logistic regression analysis demonstrated that the presence of peripheral artery disease was related to the coronary variety (Odds ratio [OR]: 6, 95% CI: 1.4-25.5, P = 0.016) and severe cases (diffused atherosclerotic stenosis and complete occlusion in all segments) significantly indicated the presence of some coronary pathology (OR: 8, 95% CI: 1.7-37.4, P = 0.008). This relationship maintained its significance after adjustment for age, gender, hypercholesterolaemia, smoking, hypertension, diabetes, family

  4. Relationship of Hemoglobin to Arterial Oxygen Desaturation during Aeromedical Evacuation

    DTIC Science & Technology

    2015-04-02

    AFRL-SA-WP-SR-2015-0007 Relationship of Hemoglobin to Arterial Oxygen Desaturation during Aeromedical Evacuation Jay...2. REPORT TYPE Special Report 3. DATES COVERED (From – To) September 2012 – September 2014 4. TITLE AND SUBTITLE Relationship of Hemoglobin to...oxygen carrying capability ( hemoglobin ). The incidence and severity of hypoxemia during AE of non- critically injured casualties have not been

  5. Relationship of the dorsalis pedis artery to the tarsal navicular.

    PubMed

    Rimchala, Chakorn; Chuckpaiwong, Bavornrit

    2015-01-01

    When undertaking surgical maneuvers about the midfoot, caution must be used to avoid injury to the dorsalis pedis artery, which courses along the dorsum of the foot on the dorsolateral aspect of the tarsal navicular. In an effort to better understand the relationship of the course of the dorsalis pedis artery relative to the tarsal navicular, 128 embalmed feet (31 [48.4%] female and 33 [51.6%] male cadavers aged 15 to 91 years) were measured. The dorsalis pedis artery was dissected from its origin to its termination (i.e., the first dorsal metatarsal artery and the deep plantar perforating artery), and the distance from the medial cortex of the navicular tuberosity to the medial margin of the artery and the location of the artery as a percentage of the medial-to-lateral width of the navicular were measured. In the male cadaver specimens, the distance from the navicular tuberosity to the dorsalis pedis was 23.75 ± 3.1 mm, the width of the navicular was 37.41 ± 5.0 mm, and the location of the artery as a percentage of the width of the navicular was 64.34% ± 13.1%. In the female cadaver specimens, the distance from the navicular tuberosity to the dorsalis pedis was 22.81 ± 5.5 mm, the width of the navicular was 36.11 ± 4.0 mm, and the location of the artery as a percentage of the width of the navicular was 63.29% ± 9.9%. For the right foot specimens, the distance from the navicular tuberosity to the dorsalis pedis artery was 20.29 ± 3.3 mm, and the width of the navicular was 37.21 ± 4.4 mm. For the left foot specimens, the distance from the navicular tuberosity to the dorsalis pedis was 21.40 ± 2.5 mm, and the width of the navicular was 35.92 ± 4.4 mm. The statistical comparisons between the males and females showed no statistically significant differences. In contrast, those between the right and left feet showed significant differences in the distance from the navicular tuberosity to the dorsalis pedis artery and the location of the dorsalis pedis artery

  6. Left ventricular pressure-volume diagrams and end-systolic pressure-volume relations in human beings

    SciTech Connect

    McKay, R.G.; Aroesty, J.M.; Heller, G.V.; Royal, H.; Parker, J.A.; Silverman, K.J.; Kolodny, G.M.; Grossman, W.

    1984-02-01

    Assessment of left ventricular pressure-volume relations serially in response to altered loading conditions and heart rate has been difficult to achieve with contrast ventriculography. Accordingly, to study changing pressure-volume relations during altered loading and heart rate, left ventricular pressure and radionuclide absolute volume curves (obtained using a counts-based method with attenuation factor corrections) were recorded in 20 patients. Ventricular pressure and radionuclide volume curves were digitized and synchronized to end-diastole, and pressure-volume plots were subsequently constructed from 32 pressure-volume coordinates throughout the cardiac cycle. In all patients, the correlation between radionuclide absolute volumes and angiographic ventricular volumes was r . 0.92. In 10 patients in whom both radionuclide and angiographic pressure-volume diagrams were constructed, the agreement between the two methods was excellent. With this method, end-systolic pressure-volume relations were examined during altered left ventricular loading conditions, pacing-induced incremental increases in heart rate and pacing-induced ischemia. Using pharmacologically induced changes in left ventricular loading conditions, the slope and volume intercept of the end-systolic pressure-volume line could be calculated as a means of assessing basal contractility. During pacing-induced tachycardia, the slope and volume intercept of the end-systolic pressure-volume line could be calculated to quantify the Treppe effect and assess negative inotropic changes secondary to ischemia. This study supports the validity of using serial recordings of left ventricular pressure and radionuclide volumes to assess left ventricular pressure-volume relations, and indicates that this approach may be useful in the analysis of end-systolic pressure-volume relations in patients.

  7. Left ventricular pressure-volume diagrams and end-systolic pressure-volume relations in human beings.

    PubMed

    McKay, R G; Aroesty, J M; Heller, G V; Royal, H; Parker, J A; Silverman, K J; Kolodny, G M; Grossman, W

    1984-02-01

    Assessment of left ventricular pressure-volume relations serially in response to altered loading conditions and heart rate has been difficult to achieve with contrast ventriculography. Accordingly, to study changing pressure-volume relations during altered loading and heart rate, left ventricular pressure and radionuclide absolute volume curves (obtained using a counts-based method with attenuation factor corrections) were recorded in 20 patients. Ventricular pressure and radionuclide volume curves were digitized and synchronized to end-diastole, and pressure-volume plots were subsequently constructed from 32 pressure-volume coordinates throughout the cardiac cycle. In all patients, the correlation between radionuclide absolute volumes and angiographic ventricular volumes was r = 0.92. In 10 patients in whom both radionuclide and angiographic pressure-volume diagrams were constructed, the agreement between the two methods was excellent. With this method, end-systolic pressure-volume relations were examined during altered left ventricular loading conditions, pacing-induced incremental increases in heart rate and pacing-induced ischemia. Using pharmacologically induced changes in left ventricular loading conditions, the slope and volume intercept of the end-systolic pressure-volume line could be calculated as a means of assessing basal contractility. During pacing-induced tachycardia, the slope and volume intercept of the end-systolic pressure-volume line could be calculated to quantify the Treppe effect and assess negative inotropic changes secondary to ischemia. This study supports the validity of using serial recordings of left ventricular pressure and radionuclide volumes to assess left ventricular pressure-volume relations, and indicates that this approach may be useful in the analysis of end-systolic pressure-volume relations in patients.

  8. The Relationship between Occupational Metal Exposure and Arterial Compliance

    PubMed Central

    Wong, Jason Y.Y.; Fang, Shona C.; Grashow, Rachel; Fan, Tianteng; Christiani, David C.

    2015-01-01

    Background The objective of this study was to evaluate the relationship between cumulative occupational exposure to various metals and arterial compliance in welders. Methods The observational follow-up study consisted of 25 subjects. Levels of nickel (Ni), lead (Pb), cadmium (Cd), manganese (Mn), and arsenic (As) from toenails were assessed using mass spectrometry. Arterial compliance as reflected by augmentation index (AIx) was measured using SphygmoCor Px Pulse Wave Analysis System. Linear regression models were used to assess the associations. Results For every 1 unit increase in log-transformed toenail Ni, there was a statistically significant 5.68 (95%CI: 1.38, 9.98, p=0.01) unit increase in AIx. No significant associations were found between AIx and Pb, Cd, Mn, and As. Conclusions Cumulative Ni exposure is associated with increased arterial stiffness in welders and may increase risk of adverse cardiovascular outcomes. PMID:25738948

  9. Regional blood flow analysis and its relationship with arterial branch lengths and lumen volume in the coronary arterial tree

    NASA Astrophysics Data System (ADS)

    Molloi, Sabee; Wong, Jerry T.

    2007-03-01

    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 \\frac34 power 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 \\frac34 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.

  10. Pressure-volume regulation in hypertension.

    PubMed

    Hall, J E; Guyton, A C; Brands, M W

    1996-06-01

    In all forms of hypertension, including human essential hypertension, pressure natriuresis is abnormal because sodium excretion is the same as in normotension despite increased arterial pressure. Considerable evidence indicates that this resetting of pressure natriuresis plays a key role in causing hypertension, rather than merely occurring as an adaptation to increased blood pressure. Because human essential hypertension is a heterogeneous disease, it is likely that multiple neurohumoral and intrarenal defects contribute to abnormal pressure natriuresis and increased blood pressure. Physiological studies have shown that renal abnormalities that cause increased distal and collecting tubule reabsorption, decreased glomerular filtration coefficient or loss of nephrons also cause decreased slope of pressure natriuresis (salt-sensitive hypertension), whereas increased preglomerular resistance causes a parallel shift of pressure natriuresis (salt-insensitive hypertension). Comparison of the characteristics of pressure natriuresis (such as salt-sensitivity of blood pressure) in hypertensive subjects with those forms of experimental hypertension of known origin can provide insight into the etiology of human hypertension. With long-standing hypertension, pathological changes in the glomeruli and renal arterioles may further shift pressure natriuresis and exacerbate hypertension.

  11. Arterial stiffness identification of the human carotid artery using the stress-strain relationship in vivo

    PubMed Central

    Khamdaeng, T.; Luo, J.; Vappou, J.; Terdtoon, P.; Konofagou, E.E.

    2014-01-01

    Arterial stiffness is well accepted as a reliable indicator of arterial disease. Increase in carotid arterial stiffness has been associated with carotid arterial disease, e.g., atherosclerotic plaque, thrombosis, stenosis, etc. Several methods for carotid arterial stiffness assessments have been proposed. In this study, in-vivo noninvasive assessment using applanation tonometry and an ultrasound-based motion estimation technique was applied in seven healthy volunteers (age 28 ± 3.6 years old) to determine pressure and wall displacement in the left common carotid artery (CCA), respectively. The carotid pressure was obtained using a calibration method by assuming that the mean and diastolic blood pressures remained constant throughout the arterial tree. The regional carotid arterial wall displacement was estimated using a 1D cross-correlation technique on the ultrasound radio frequency (RF) signals acquired at a frame rate of 505–1010 Hz. Young’s moduli were estimated under two different assumptions: (i) a linear elastic two-parallel spring model and (ii) a two-dimensional, nonlinear, hyperelastic model. The circumferential stress (σθ) and strain (εθ) relationship was then established in humans in vivo. A slope change in the circumferential stress-strain curve was observed and defined as a transition point. The Young’s moduli of the elastic lamellae (E1), elastin-collagen fibers (E2) and collagen fibers (E3) and the incremental Young’s moduli before (E0≤εθ<ε0T) and after the transition point (EεθT≤εθ) were determined from the first and second approach, respectively, to describe the contribution of the complex mechanical interaction of the different arterial wall constituents. The average E1, E2 and E3 from seven healthy volunteers were found to be equal to 0.15 ± 0.04, 0.89 ± 0.27 and 0.75 ± 0.29 MPa, respectively. The average E0≤εθ<εθTInt and EεθT≤εθInt of the intact wall (both the tunica adventitia and tunica media layers

  12. Arterial stiffness identification of the human carotid artery using the stress-strain relationship in vivo.

    PubMed

    Khamdaeng, T; Luo, J; Vappou, J; Terdtoon, P; Konofagou, E E

    2012-03-01

    Arterial stiffness is well accepted as a reliable indicator of arterial disease. Increase in carotid arterial stiffness has been associated with carotid arterial disease, e.g., atherosclerotic plaque, thrombosis, stenosis, etc. Several methods for carotid arterial stiffness assessment have been proposed. In this study, in vivo noninvasive assessment using applanation tonometry and an ultrasound-based motion estimation technique was applied in seven healthy volunteers (age 28±3.6years old) to determine pressure and wall displacement in the left common carotid artery (CCA), respectively. The carotid pressure was obtained using a calibration method by assuming that the mean and diastolic blood pressures remained constant throughout the arterial tree. The regional carotid arterial wall displacement was estimated using a 1D cross-correlation technique on the ultrasound radio frequency (RF) signals acquired at a frame rate of 505-1010Hz. Young's moduli were estimated under two different assumptions: (i) a linear elastic two-parallel spring model and (ii) a two-dimensional, nonlinear, hyperelastic model. The circumferential stress (σ(θ)) and strain (ɛ(θ)) relationship was then established in humans in vivo. A slope change in the circumferential stress-strain curve was observed and defined as the transition point. The Young's moduli of the elastic lamellae (E(1)), elastin-collagen fibers (E(2)) and collagen fibers (E(3)) and the incremental Young's moduli before ( [Formula: see text] ) and after the transition point ( [Formula: see text] ) were determined from the first and second approach, respectively, to describe the contribution of the complex mechanical interaction of the different arterial wall constituents. The average moduli E(1), E(2) and E(3) from seven healthy volunteers were found to be equal to 0.15±0.04, 0.89±0.27 and 0.75±0.29MPa, respectively. The average moduli [Formula: see text] and [Formula: see text] of the intact wall (both the tunica

  13. Pressure-volume characteristics of the intact and disrupted pelvic retroperitoneum.

    PubMed

    Grimm, M R; Vrahas, M S; Thomas, K A

    1998-03-01

    Hemorrhage is a major cause of mortality in pelvic fractures. Bleeding can be controlled in hypotensive patients by direct ligation, angiographic embolization, pelvic packing, and acute external fixation. Acute application of an external fixator can reduce pelvic volume and reduce bleeding fractures to effect tamponade. This therapy assumes that the pelvis represents a closed space, which clearly is not true anatomically. However, the premise may hold functionally. This study explored the relationship between pressure and volume in the intact and disrupted pelvic retroperitoneum. In cadaveric specimens, the external iliac vein was dissected, ruptured, and cannulated. This method allowed controlled flow of fluid, with simultaneous measurement of pressure, into the intact retroperitoneum. Open book pelvic fractures were created by applying external rotation to the pelvis through the femoral heads. The pressure-volume measurements, without and with external fixation applied, were repeated after the fracture, as well as after a laparotomy. In the intact retroperitoneum, pressures rapidly rose to an average of 30 mm Hg after infusion of 5 liters of fluid. After fracture, up to 20 liters of fluid could be infused at pressures not exceeding 35 mm Hg. External fixation increased pressures approximately 3 mm Hg at low fluid volumes, and approximately 11 mm Hg at the highest fluid volumes. Laparotomy decreased retroperitoneal pressure from approximately 35 mm Hg to approximately 15 mm Hg. The results of the study suggest that low-pressure venous hemorrhage may be tamponaded by an external fixator, given that enough fluid volume is present in the pelvic retroperitoneum. However, external fixation may not generate sufficient pressure to stop arterial bleeding. In any case, it seems that a large volume of fluid must be lost into the pelvis before an external fixator can have much effect on retroperitoneal pressures.

  14. Utilization of pressure-volume curves in the pediatric patient.

    PubMed

    Bone, R C; Jantzen, D; Heithold, R

    1978-04-01

    Seven patients treated with continuous mechanical ventialtion were monitored with static and dynamic pressure-volume curves. Three patients developed no pulmonary complications, and mechanical ventilation was discontinued within 96 hr. In four patients, pressure-volume curves were used as a diagnostic aid in the detection of the physiologic defect resulting from bronchoconstriction, atelectasis, loculated pleural fluid, pulmonary edema, and mucous plugging. These measurements were also utilized to evaluate the effectivess of therapeutic modalities such as treatment of bronchoconstriction with bronchodilators, mucous plugging with adequate suctioning, and drainage of loculated pleural effusion. Pressure-v-lume measurements are simple, noninvasive, and require the smae equipment used in continuous mechanical ventilation. Pressure-volume monitoring of pediatric patients with curves warrants further investigation to evaluate its value.

  15. Relationship of Inflammatory Biomarkers with Severity of Peripheral Arterial Disease

    PubMed Central

    Toyofuku, Takahiro; Inoue, Yoshinori

    2016-01-01

    Objective. The pentraxin family, including high-sensitivity C-reactive protein (hs-CRP), serum amyloid P (SAP), and pentraxin 3 (PTX3), has been identified as playing a key role in inflammatory reactions such as in atherosclerosis and cardiovascular disease. In this study, we examined the relationship between peripheral arterial disease (PAD) and serum levels of pentraxins. Methods. This study was undertaken via a retrospective review of PAD patients with surgical intervention for lesions of the common femoral artery. We evaluated the preoperative patient conditions, hemodynamic status, such as ankle brachial index (ABI), and clinical ischemic conditions according to Rutherford classification. Preoperatively, we collected blood samples for determining the serum levels of hs-CRP, SAP, and PTX3. Results. Twelve PAD patients with common femoral arterial lesions were treated and examined. The hemodynamic severity of PAD was not negatively correlated with hs-CRP, SAP, or PTX3. The clinical severity evaluated by Rutherford classification was significantly positively correlated with the serum level of PTX3 (p = 0.019). Conclusion. We demonstrated that PTX3 might be a better marker of PAD than hs-CRP and SAP. Furthermore, PTX3 might be a prognostic marker to evaluate the severity of PAD. PMID:27559483

  16. Pressure-Volume Integral Expressions for Work in Irreversible Processes

    ERIC Educational Resources Information Center

    Gislason, Eric A.; Craig, Norman C.

    2007-01-01

    Different formulations of thermodynamic work "w" as a pressure-volume integral are examined for a piston moving against a gas in an irreversible process. Proper expressions are obtained using the instantaneous pressure of the gas on the piston as the integrand and also using certain external pressures as the integrand. There are two common yet…

  17. Arterial relationships to the nerves and some rigid structures in the posterior cranial fossa.

    PubMed

    Surchev, N

    2008-09-01

    The close relationships between the cranial nerves and the arterial vessels in the posterior cranial fossa are one of the predisposing factors for artery-nerve compression. The aim of this study was to examine the relationships of the vertebral and basilar arteries to some skull and dural structures and the nerves in the posterior cranial fossa. For this purpose, the skull bases and brains of 70 cadavers were studied. The topographic relationships of the vertebral and basilar arteries to the cranial nerves in the posterior cranial fossa were studied and the distances between the arteries and some osseous formations were measured. The most significant variations in arterial position were registered in the lower half of the basilar artery. Direct contact with an artery was established for the hypoglossal canal, jugular tubercle, and jugular foramen. The results reveal additional information about the relationships of the nerves and arteries to the skull and dural formations in the posterior cranial fossa. New quantitative information is given to illustrate them. The conditions for possible artery-nerve compression due to arterial dislocation are discussed and two groups (lines) of compression points are suggested. The medial line comprises of the brain stem points, usually the nerve root entry/exit zone. The lateral line includes the skull eminences, on which the nerves lie, or skull and dural foramina through which they exit the cranial cavity. (c) 2008 Wiley-Liss, Inc.

  18. Relationship Between Brachial Artery Flow-Mediated Dilation, Carotid Artery Intima-Media Thickness and Coronary Flow Reserve in Patients With Coronary Artery Disease

    PubMed Central

    Oz, Fahrettin; Elitok, Ali; Bilge, Ahmet Kaya; Mercanoglu, Fehmi; Oflaz, Huseyin

    2012-01-01

    Background The aim of this study was to assess the relationship between brachial artery flow mediated dilation (FMD), carotid artery intima-media thickness (IMT) and coronary flow reserve (CFR) in patients with coronary artery disease (CAD). Methods Fifty patients with coronary artery disease, except left anterior descending artery (LAD), who showed no cardiac symptoms and 45 control subjects underwent assessment of brachial artery FMD, carotid artery intima-media thickness by high-resolution ultrasound. In addition, transthoracic second harmonic Doppler echocardiography was used to measure CFR. Results All of the parameters were found to be correlated with each other. CFR correlated with brachial artery FMD (r = 0.232, P < 0.05) and with carotid IMT (r = -0.403, P < 0.001). Carotid IMT correlated with brachial artery FMD (r = -0.211, P < 0.05). Conclusion Transthoracic CFR correlated with well-established noninvasive predictors of atherosclerosis and we suggest that it can be used as a surrogate for coronary atherosclerosis.

  19. Non-invasive quantification of peripheral arterial volume distensibility and its non-linear relationship with arterial pressure.

    PubMed

    Zheng, Dingchang; Murray, Alan

    2009-05-29

    Arterial wall function is associated with different physiological and clinical factors. Changes in arterial pressure cause major changes in the arterial wall. This study presents a simple non-invasive method to quantify arterial volume distensibility changes with different arterial pressures. The electrocardiogram, finger and ear photoplethysmogram were recorded from 15 subjects with the right arm at five different positions (90 degrees , 45 degrees , 0 degrees , -45 degrees and -90 degrees referred to the horizontal level). Arm pulse propagation time was determined by subtracting ear pulse transit time from finger pulse transit time, and was used to obtain arterial volume distensibility. The mean arterial blood pressure with the arm at the horizontal level was acquired, and changes with position were calculated using the hydrostatic principle that blood pressure in the arm is linearly related to its vertical distance from the horizontal level. The mean arm pulse propagation times for the five different positions were 88, 72, 57, 54 and 52ms, with the corresponding mean arterial volume distensibility of 0.234%, 0.158%, 0.099%, 0.088% and 0.083% per mmHg. For all consecutive changes in arm position, arm pulse propagation time and arterial volume distensibility, were significantly different (all probability P<0.05). The slopes of arm pulse propagation time and arterial volume distensibility against arterial pressure decreased significantly between each consecutive arm position from 90 degrees to -45 degrees (all P<0.01), indicating significant non-linearity. The experimental results fitted the physiological exponential model and Langewouters' arctangent model well, and were also comparable to published data with arterial volume distensibility approximately tripling for transmural pressure changes from 101 to 58mmHg. In conclusion, the inverse and non-linear relationship between arterial volume distensibility and arterial pressure has been quantified using a simple

  20. Relationship between retinal blood flow and arterial oxygen

    PubMed Central

    Cheng, Richard W.; Yusof, Firdaus; Tsui, Edmund; Jong, Monica; Duffin, James; Flanagan, John G.; Fisher, Joseph A.

    2016-01-01

    Key points Vascular reactivity, the response of the vessels to a vasoactive stimulus such as hypoxia and hyperoxia, can be used to assess the vascular range of adjustment in which the vessels are able to compensate for changes in PO2.Previous studies in the retina have not accurately quantified retinal vascular responses and precisely targeted multiple PaO2 stimuli at the same time as controlling the level of carbon dioxide, thus precluding them from modelling the relationship between retinal blood flow and oxygen.The present study modelled the relationship between retinal blood flow and PaO2, showing them to be a combined linear and hyperbolic function.This model demonstrates that the resting tonus of the vessels is at the mid‐point and that they have great vascular range of adjustment, compensating for decreases in oxygen above a P ETC O2 of 32–37 mmHg but being limited below this threshold. Abstract Retinal blood flow (RBF) increases in response to a reduction in oxygen (hypoxia) but decreases in response to increased oxygen (hyperoxia). However, the relationship between blood flow and the arterial partial pressure of oxygen has not been quantified and modelled in the retina, particularly in the vascular reserve and resting tonus of the vessels. The present study aimed to determine the limitations of the retinal vasculature by modelling the relationship between RBF and oxygen. Retinal vascular responses were measured in 13 subjects for eight different blood gas conditions, with the end‐tidal partial pressure of oxygen (P ETC O2) ranging from 40–500 mmHg. Retinal vascular response measurements were repeated twice; using the Canon laser blood flowmeter (Canon Inc., Tokyo, Japan) during the first visit and using Doppler spectral domain optical coherence tomography during the second visit. We determined that the relationship between RBF and PaO2 can be modelled as a combination of hyperbolic and linear functions. We concluded that RBF compensated for

  1. Relationship of effective arterial elastance to demographic and arterial characteristics in normotensive and hypertensive adults.

    PubMed

    Saba, P S; Roman, M J; Ganau, A; Pini, R; Jones, E C; Pickering, T G; Devereux, R B

    1995-09-01

    To evaluate demographic and vascular correlates of the effective arterial elastance noninvasively in normotensive and hypertensive adults. In 202 subjects carotid ultrasonography and external arterial tonometry were simultaneously performed; carotid cross-sectional area, absolute and relative wall thicknesses, Peterson's and Young's elastic moduli and beta', a pressure-dependent index of arterial stiffness, were calculated. The impact of reflected waves on central pressure waveforms was evaluated by the 'augmentation index' (the relative increment in systolic pressure caused by the late-systolic peak). Left ventricular mass and relative wall thickness were assessed echocardiographically. The effective arterial elastance was estimated by dividing the pressure at the dicrotic notch by the Doppler-determined stroke index. The effective arterial elastance was higher in women among normotensives but similar between sexes among hypertensive subjects. It was correlated to age, mean blood pressure, body mass index and measures of arterial function, including Peterson's and Young's elastic moduli and beta', and to the augmentation index. It was also related to absolute and relative carotid wall thicknesses, lumen diameter and indexed cross-sectional area. Age, beta' and carotid cross-sectional area independently predicted effective arterial elastance in multiple regression analysis. Effective arterial elastance is related to demographic and arterial structural and functional characteristics. Increases in effective arterial elastance resulting from altered arterial structure and function may play a role in inducing left ventricular adaptative modifications.

  2. The Relationship Between Blood Monocyte Count and Coronary Artery Ectasia

    PubMed Central

    Demir, Mehmet; Demir, Canan; Keceoglu, Serdar

    2014-01-01

    Background The pathophysiology of coronary artery ectasia (CAE) has not been clearly identified, although multiple abnormalities including arteritis, endothelial dysfunction, and atherothrombosis have been reported. It is known that monocytes play an important role in inflammation, atherosclerosis and cardiovascular disease. We aimed to compare the numbers of monocyte counts of the CAE patients versus controls. Method This study included 84 CAE patients (40 male, mean age 55.4 ± 9.7 years) and 30 controls (10 male, mean age 57.86 ± 11.6 years). Concurrent routine biochemical tests and neutrophil, lymphocyte, monocyte count and mean platelet volume (MPV) on whole blood count were performed for these participants. These parameters were compared between groups. Results Baseline characteristics of the study groups were comparable. CAE patients had a higher MPV value and monocyte count than controls (8.8 ± 0.2 vs. 6.2 ± 1.6 fL and 732 ± 88 vs. 321 ± 75 cell/μL; both P < 0.001, respectively). Conclusion As a result, our study revealed a relationship between monocyte count and MPV in patients with CAE. PMID:28348713

  3. The Relationship Between Plasma Eosinophil Count and Coronary Artery Ectasia

    PubMed Central

    Demir, Mehmet; Keceoglu, Serdar; Melek, Mehmet

    2013-01-01

    Background The pathophysiology of coronary artery ectasia (CAE) has not been clearly identified, although multiple abnormalities including arteritis, endothelial dysfunction, and atherothrombosis have been reported. It is known that eosinophils play an important role in inflammation and thrombosis. Also vascular anomalies such as aneurysm have been noted in patients with hypereosinophilic syndromes. We aimed to compare the numbers of eosinophil counts of the patients CAE versus controls. Methods This study included 50 CAE patients (20 male, mean age 60.26 ± 10.6 years) and 30 control person (10 male, mean age 57.86 ± 11.6 years). These participants were performed concurrent routine biochemical tests and neutrophil, lymphocyte, eosinophil count and mean platelet volume (MPV) on whole blood count. These parameters were compared between groups. Results Baseline characteristics of the study groups were comparable. CAE patients had a higher MPV value, eosinophil, neutrophil lymphocyte ratio (NLR) than controls (8.5 ± 1 vs 76.2 ± 1.6 fl and 0.198 ± 0.14 vs 0.093 ± 0.058 and 3.0 ± 2.5vs 1.14 ± 0.9; P < 0.001, 0.002 and 0.028 respectively). Conclusion As a result, our study revealed a relationship between eosinophil count, NLR and MPV in patients with CAE.

  4. Arterial stiffness and hand osteoarthritis: a novel relationship?

    PubMed Central

    Saleh, A. S.; Najjar, S. S.; Muller, D. C.; Shetty, V.; Ferrucci, L.; Gelber, A. C.; Ling, S. M.

    2009-01-01

    Summary Objective Osteoarthritis (OA) and vascular stiffening may share elements of common pathogenesis, but their potential relatedness has been the focus of little prior inquiry. We tested the hypothesis that these two aging-associated conditions are related to each other. Method We analyzed cross-sectional data from 256 participants of the Baltimore Longitudinal Study of Aging (BLSA), a study of normative aging. All underwent measurement of arterial pulse wave velocity (PWV), an index of vascular stiffness, as well as hand radiographs that were graded for evidence of OA. Twenty total joints across three joint groups (distal interphalangeal [DIP], proximal interphalangeal [PIP], carpal-metacarpal [CMC]) were each assigned a Kellgren–Lawrence grade (K–L) of 0 (normal) through 4 (severe), with K–L grades ≥2 considered evidence of definite OA. Radiographic hand OA was defined as definite OA changes in at least two of the three anatomic hand sites (DIP, PIP, CMC). OA burden was represented by the total number of affected OA joints, and a cumulative K–L grade was aggregated across all hand joint groups. The relationship of PWV with these three measures of hand OA was assessed by linear regression. Results Upon univariate analysis, the presence of radiographic hand OA (β = 218.1, P < 0.01), the total number of OA joints (β = 32.9, P < 0.01), and the cumulative K–L grade across all joint groups (β = 12.2, P < 0.01) were each associated with increased PWV. These associations, however, were no longer significant in age-adjusted models. Conclusion Although significant individual relationships between PWV and several measures of hand OA were observed, these associations were largely attributable to the confounding effect of age. PMID:17097316

  5. The relationships of the pulmonary arteries to lung lesions aid in differential diagnosis using computed tomography.

    PubMed

    Lin, Chien-Heng; Li, Tsai-Chung; Tsai, Po-Pang; Lin, Wei-Ching

    2015-06-01

    The improvement of the resolution of rapid scanning in multidetector computed tomography (CT) has an increased accuracy that allows for the demonstration of the relationship of the pulmonary arteries and lung lesions, even in the peripheral lung. The purpose of this study is to evaluate the relationship between the pulmonary arteries and lung lesions by CT, and to use this relationship to distinguish between benign and malignant lung lesions. The relationships of the lung lesions and the adjacent pulmonary artery were recorded as encasement, displacement, penetration, in the margin, and disconnection. Statistical analyses were then performed to evaluate the relationship of the pulmonary arteries to each lesion with a focus toward the possibility of malignancy and the degree of pulmonary arterial encasement in the lesion. The relationship between the pulmonary arteries and lung lesions had a statistically significant difference between benignancy and malignancy (P < 0.001). Inter-observer agreement was substantial (κ = 0.639; 95% CI: 0.518-0.719). The average degrees of pulmonary arterial encasement in benign and malignant lesions were 52.1% ± 27.3% and 71.8% ± 18.8%, respectively (P = 0.011). The ROC curve showed that the degree of pulmonary arterial encasement had a moderate discriminating ability in diagnosing lung carcinoma, and the area under the curve was 0.738. The best cutoff value was 44.4%. The relationships of the pulmonary arteries to lung lesions and the degree of pulmonary arterial encasement could be used in differentiating benignancy from malignancy not only for central lung lesions but also peripheral lung lesions.

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

    SciTech Connect

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

    2011-08-01

    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 ({beta}), augmentation index (AI) and one-point pulse wave velocity (PWV-{beta}) 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

  7. Relationship between the Direction of Ophthalmic Artery Blood Flow and Ocular Microcirculation before and after Carotid Artery Stenting

    PubMed Central

    Sato, Kenichiro

    2016-01-01

    When internal carotid artery stenosis is accompanied by ocular ischemic syndrome, intervention is recommended to prevent irreversible visual loss. In this study, we used laser speckle flowgraphy to measure the ocular microcirculation in the optic nerve head before and after carotid artery stenting (CAS) of 40 advanced internal carotid stenosis lesions from 37 patients. The aim was to investigate the relationship between ocular microcirculation and the direction of ophthalmic artery blood flow obtained by angiography. We found that there was a significant increase in blood flow after CAS (P = 0.003). Peak systolic velocity as an indicator of the rate of stenosis was also significantly higher in the group with retrograde/undetected flow of the ophthalmic artery than in the group with antegrade flow (P = 0.002). In all cases where retrograde flow of the ophthalmic artery was observed before stenting, the flow changed to antegrade after stenting. Through the use of laser speckle flowgraphy, this study found that CAS can improve ocular microcirculation. Furthermore, while patients displaying retrograde flow of the ophthalmic artery before stenting have a poor prognosis, CAS corrected the flow to antegrade, suggesting that visual loss can be prevented by improving the ocular microcirculation. PMID:28070413

  8. The relationship between coronary artery disease and pericoronary epicardial adipose tissue thickness.

    PubMed

    Aydın, Ayşe Murat; Kayalı, Alperen; Poyraz, Ahmet Kurşad; Aydın, Kemal

    2015-02-01

    A retrospective study to investigate the relationship between epicardial adipose tissue thickness (EATT) and presence of coronary artery plaque, coronary artery disease (CAD) and CAD risk factors. Multidetector computed tomography (MDCT) coronary angiography images were reviewed. Left anterior decending artery, right coronary artery and left circumflex artery pericoronary EATT were measured. Demographic, clinical and CAD risk factor data were obtained from medical records. Patients with CAD (n = 49) had significantly larger mean EATT than those without CAD (n = 101). Pericoronary EATT was significantly correlated with body mass index, total cholesterol level, coronary artery calcium score, hypertension and diabetes mellitus history. There is an association between pericoronary EATT and CAD, as well as CAD risk factors. Pericoronary EATT measurement may become a widely used, easy-to-perform method for determining CAD risk. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  9. Spousal relationship quality and cardiovascular risk: dyadic perceptions of relationship ambivalence are associated with coronary-artery calcification.

    PubMed

    Uchino, Bert N; Smith, Timothy W; Berg, Cynthia A

    2014-04-01

    The quality of spousal relationships has been related to physical-health outcomes. However, most studies have focused on relationship positivity or negativity in isolation, despite the fact that many close relationships are characterized by both positive and negative aspects (i.e., ambivalence). In addition, most work has not accounted for the reciprocal nature of close-relationship processes that can have an impact on health. Using a sample of 136 older married couples, we tested whether actor-partner models of relationships that were either primarily positive or ambivalent (i.e., perceived as having both helpful and upsetting aspects) predicted measures of coronary-artery calcification. Results revealed an Actor × Partner interaction whereby coronary-artery calcification scores were highest for individuals who both viewed and were viewed by their spouse as ambivalent. These data are discussed in light of the importance of considering both positive and negative aspects of relationship quality and modeling the interdependence of close relationships.

  10. Moment-to-moment characteristics of the relationship between arterial pressure and renal interstitial hydrostatic pressure.

    PubMed

    Komolova, Marina; Adams, Michael A

    2010-10-01

    The kidney is a key controller of the long-term level of arterial pressure, in part through pressure-natriuresis. Although direct coupling of changes in renal arterial pressure to renal interstitial hydrostatic pressure (RIHP) and consequent sodium excretion is well established, few studies have characterized the moment-to-moment aspects of this process. These studies characterized the short-term hemodynamic component of pressure-natriuresis in vivo before and after autonomic nervous system and renin-angiotensin system inhibition. Changes in RIHP were determined over a range of renal arterial pressures in Wistar rats receiving no treatment, a ganglionic blocker (hexamethonium; 20 mg/kg per hour IV), or an angiotensin II type 1 receptor blocker (losartan; 10 mg/kg per hour IV). After a series of changes in renal arterial pressure, a delay of only ≈1 second was found for the onset of RIHP responses that was independent of the stimulus magnitude and neurohumoral manipulation; however, completion of the full RIHP response was within ≈15 seconds for renal arterial pressure changes of ≤30 mm Hg. The overall slope of the renal arterial pressure- RIHP relationship (0.09±0.01) was also not affected by autonomic nervous system and renin-angiotensin system inhibition despite decreasing renal arterial pressure (↓40% and ↓28%, respectively). Separate assessment of this relationship above and below the prevailing arterial pressure revealed that the pressor versus the depressor portion was blunted (P<0.001), a difference that was abolished after autonomic nervous system and renin-angiotensin system inhibition. The results suggest that spontaneous changes in arterial pressure are coupled to moment-to-moment changes in RIHP over a wide range of pressures, emphasizing a likely role for the dynamic component of the renal arterial pressure-RIHP relationship in the modulation of sodium excretion and, hence, arterial pressure.

  11. [Response of cardiac patients to dynamic exercise: analysis with "systolic" pressure-volume area].

    PubMed

    Yagi, Y; Goto, K; Ooshima, S; Takatsu, H; Tsukamoto, T; Iida, M; Yamamoto, N; Deguchi, F; Terashima, Y; Hirakawa, S

    1989-09-01

    In the present study, we constructed a left ventricular pressure-volume loop from catheterization data and RN-angiocardiography. By connecting the point of origin of the plane, not the point of Vd, with the end-systolic point of the loop, we calculated a "systolic" pressure-volume area (PVA), elastic potential energy (EPE), and stroke work (SW). A cardiac output (CO)-pulmonary artery wedge (PAW) pressure plot was constructed at rest and during exercise, using a bicycle ergometer, to evaluate cardiac pump function. End-systolic volume (ESV) was obtained from the left ventricular P-V loop, and the response of ESV to exercise was investigated. Thirty-five patients with various cardiac diseases were categorized in two groups according to the delta CO/delta PAW obtained from the shift of the CO-PAW plot during exercise; group I (n = 28) with the properly functioning hearts having the ratio greater than 0.12 l/min/mmHg and group II (n = 7) with the poorly functioning hearts having the ratio less than or equal to 0.12 l/min/mmHg. Group I was subdivided further into two subsets according to the changing pattern of ESV during exercise; group I-A with decreased or unchanged ESV (n = 20) and group I-B with increased ESV in which end-diastolic volume (EDV) was increased during exercise (n = 8). During exercise, PVA and SW were unchanged but SW/PVA increased in group I-A, suggesting improvement of external mechanical efficiency. SW/PVA was unchanged in group I-B, despite the increase in PVA and SW. This suggested that external mechanical work increased as a result of increased cardiac oxygen consumption. In group II, PVA increased, SW was unchanged and SW/PVA decreased, which could be explained by the mechanism that external mechanical work during exercise decreased as compared with that at rest. It was suggested that a different mechanism may have been responsible for the production of external mechanical work among patients in group I-A and in group I-B with properly

  12. The relationship between intracranial arterial stenosis and glomerular filtration rate.

    PubMed

    Kang, Kyusik; Hwang, Young-Hwan

    2012-10-01

    Poor renal function is associated with cardiovascular complications attributable to large-vessel diseases such as arterial calcification, heart failure, myocardial infarction, and cardiac mortality. The aim of this study was to evaluate the association between renal function and intracranial arterial stenosis (IAS). We analyzed the records of 283 stroke-free Korean adults (≥45 years of age) who underwent brain 3D time-of-flight magnetic resonance angiography as part of their voluntary health check. The presence of stenosis in the basilar artery and in the horizontal portion of the middle cerebral artery was defined as narrowing of the luminal diameter by 25% or more or occlusion on brain magnetic resonance angiography. We estimated the glomerular filtration rate using the Modification of Diet in Renal Disease equation. The subjects were 133 men and 150 women (mean age of 56 ± 7 years). One hundred sixty-six subjects (59 %) had IAS. The serum creatinine concentration in the highest quartile compared with the lowest quartile was associated with increased prevalence of IAS; the eGFR in the upper two quartiles compared with the lowest quartile were associated with decreased prevalence of IAS. The prevalence of subjects with a high eGFR decreased significantly with the severity of IAS. In conclusion, poor renal function is associated with the presence and the degree of IAS in stroke-free Korean adults.

  13. The relationship between elevated magnesium levels and coronary artery ectasia.

    PubMed

    Yolcu, Mustafa; Ipek, Emrah; Turkmen, Serdar; Ozen, Yücel; Yildirim, Erkan; Sertcelik, Alper; Ulusoy, Fatih Rifat

    Coronary artery ectasia (CAE) without specific symptoms is the localised or diffuse swelling of the epicardial coronary arteries. Magnessium (Mg) plays an important role in cardiac excitability, vascular tonus, contractibility, reactivity and vasodilatation. In our research, we aimed to study the vasodilatory effect of Mg in the aetiopathogenesis of ectasia. Patients identified during routine coronary angiograms in our clinic between January 2010 and 2013 were included in the study. Sixty-two patients with isolated CAE, 57 with normal coronary angiograms (NCA), 73 with severe coronary artery disease (CAD), and 95 with stenosis of at least one coronary artery and CAE (CAD + CAE) were included in the study. Serum Mg levels were measured in mg/dl after 12 hours of fasting. There were no statistically significant differences between the groups in terms of age, hypertension, smoking, hyperlipidaemia, diabetes mellitus, family history of coronary artery disease and medications used. Serum glucose, thyroid stimulating hormone (TSH), urea, total cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, sodium and potassium levels were similar in all groups. Serum Mg levels were 1.90 ± 0.19 mg/dl in patients with isolated CAE, 1.75 ± 0.19 mg/dl in those with CAD, 1.83 ± 0.20 mg/dl in those with CAD + CAE, and 1.80 ± 0.16 mg/dl in the NCA group. These results show that Mg levels were higher in ectasia patients with or without CAD. The histopathological characteristics of patients with CAE were similar to those with CAD. The specific mechanism of abnormal luminal dilatation seen in CAE however remains to be elucidated. Mg is a divalent cation with powerful vasodilatory effects. In our study, serum Mg levels were found to be statistically higher in ectasia patients with or without CAD.

  14. The relationship between elevated magnesium levels and coronary artery ectasia

    PubMed Central

    Mustafa, Yolcu; Emrah, Ipek; Erkan, Yıldırım; Fatih, Rifat Ulusoy; Serdar, Turkmen; Alper, Sertcelik; Yücel, Ozen

    2016-01-01

    Summary Backround Coronary artery ectasia (CAE) without specific symptoms is the localised or diffuse swelling of the epicardial coronary arteries. Magnessium (Mg) plays an important role in cardiac excitability, vascular tonus, contractibility, reactivity and vasodilatation. In our research, we aimed to study the vasodilatory effect of Mg in the aetiopathogenesis of ectasia. Methods Patients identified during routine coronary angiograms in our clinic between January 2010 and 2013 were included in the study. Sixty-two patients with isolated CAE, 57 with normal coronary angiograms (NCA), 73 with severe coronary artery disease (CAD), and 95 with stenosis of at least one coronary artery and CAE (CAD + CAE) were included in the study. Serum Mg levels were measured in mg/ dl after 12 hours of fasting. Results There were no statistically significant differences between the groups in terms of age, hypertension, smoking, hyperlipidaemia, diabetes mellitus, family history of coronary artery disease and medications used. Serum glucose, thyroid stimulating hormone (TSH), urea, total cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, sodium and potassium levels were similar in all groups. Serum Mg levels were 1.90 ± 0.19 mg/dl in patients with isolated CAE, 1.75 ± 0.19 mg/dl in those with CAD, 1.83 ± 0.20 mg/dl in those with CAD + CAE, and 1.80 ± 0.16 mg/dl in the NCA group. These results show that Mg levels were higher in ectasia patients with or without CAD. Conclusions The histopathological characteristics of patients with CAE were similar to those with CAD. The specific mechanism of abnormal luminal dilatation seen in CAE however remains to be elucidated. Mg is a divalent cation with powerful vasodilatory effects. In our study, serum Mg levels were found to be statistically higher in ectasia patients with or without CAD. PMID:27123953

  15. The relationship between pulmonary artery acceleration time and mean pulmonary artery pressure in patients undergoing cardiac surgery: An observational study.

    PubMed

    Cowie, Brian; Kluger, Roman; Rex, Steffen; Missant, Carlo

    2016-01-01

    A noninvasive method of estimating pulmonary arterial pressures is required, as the use of the pulmonary artery catheter (PAC) is decreasing in cardiac anaesthesia. Pulmonary hypertension is defined as a mean pulmonary artery pressure (MPAP) at least 25 mmHg and this can be estimated echocardiographically by measuring the pulmonary acceleration time (PAT). This relationship has not been validated when measured using transoesophageal echocardiography (TOE) in anaesthetised patients having cardiac surgery. We hypothesised that there was a quantifiable relationship between PAT and MPAP. We aimed to assess this relationship in cardiac surgical patients undergoing general anaesthesia with TOE. An observational study. Catholic University Hospital, Leuven, Belgium, between August and December 2013. Ninety-eight patients having cardiac surgery, where intraoperative TOE was used and a PAC was inserted as part of routine care. Nil. PAT and MPAP were measured simultaneously with TOE and the PAC and this relationship was assessed. PAT and MPAP measurements were possible in all patients. There was a curvilinear relationship between PAT and MPAP with a PAT of less than 107 ms detecting pulmonary hypertension with a sensitivity of 75% and a specificity of 94.8%. The area under the receiver operating characteristic (ROC) curve was 0.87 [95% confidence interval (95% CI) 0.80 to 0.95]. Below a PAT of 107 ms, the relationship was relatively linear and could be described by the equation MPAP (mmHg) = 77 -  (0.49 x PAT). Ninety-five percent of the pressures estimated by this equation are within ±13.8 mmHg of the measured pressure. Estimation of PAT with TOE in anaesthetised cardiac surgical patients is possible. PAT is good at discriminating between patients with and without pulmonary hypertension, with a cut-off of less than 107 ms detecting pulmonary hypertension with a sensitivity of 75% and specificity of 94.8%.

  16. Relationship between radial and central arterial pulse wave and evaluation of central aortic pressure using the radial arterial pulse wave.

    PubMed

    Takazawa, Kenji; Kobayashi, Hideyuki; Shindo, Naohisa; Tanaka, Nobuhiro; Yamashina, Akira

    2007-03-01

    Since a decrease of central aortic pressure contributes to the prevention of cardiovascular events, simple measurement of not only brachial blood pressure but also central aortic pressure may be useful in the prevention and treatment of cardiovascular diseases. In this study, we simultaneously measured radial artery pulse waves non-invasively and ascending aortic pressure invasively, before and after the administration of nicorandil. We then compared changes in central aortic pressure and radial arterial blood pressure calibrated with brachial blood pressure in addition to calculating the augmentation index (AI) at the aorta and radial artery. After nicorandil administration, the reduction in maximal systolic blood pressure in the aorta (Deltaa-SBP) was -14+/-15 mmHg, significantly larger than that in early systolic pressure in the radial artery (Deltar-SBP) (-9+/-12 mmHg). The reduction in late systolic blood pressure in the radial artery (Deltar-SBP2) was -15+/-14 mmHg, significantly larger than Deltar-SBP, but not significantly different from Deltaa-SBP. There were significant relationships between Deltaa-SBP and Deltar-SBP (r=0.81, p<0.001), and between Deltaa-SBP and Deltar-SBP2 (r=0.91, p<0.001). The slope of the correlation regression line with Deltar-SBP2 (0.83) was larger and closer to 1 than that with Deltar-SBP (0.63), showing that the relationship was close to 1:1. Significant correlations were obtained between aortic AI (a-AI) and radial AI (r-AI) (before nicorandil administration: r=0.91, p<0.001; after administration: r=0.70, p<0.001). These data suggest that the measurement of radial artery pulse wave and observation of changes in the late systolic blood pressure in the radial artery (r-SBP2) in addition to the ordinary measurement of brachial blood pressure may enable a more accurate evaluation of changes in maximal systolic blood pressure in the aorta (a-SBP).

  17. Arterial Stiffness and Wave Reflection: Sex Differences and Relationship with Left Ventricular Diastolic Function

    PubMed Central

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

    2012-01-01

    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 between 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 (CABL) study using applanation tonometry. Central pulse pressure/stroke volume index (cPP/SVi), 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 two-dimensional echocardiography and tissue-Doppler imaging. Arterial stiffness and wave reflection were greater in women compared to men, independent of body size and heart rate (all p<0.01), and showed inverse relationships with parameters of diastolic function in both sexes. Further adjustment for cardiovascular risk factors attenuated these relationships; however, higher cPP/SVi predicted LV diastolic dysfunction in women [odds ratio (OR) 1.54, 95% confidence intervals (CI) 1.03–2.30] and men (OR: 2.09, 95% CI 1.30–3.39) 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. PMID:22753223

  18. Rat model of exercise-induced cardiac hypertrophy: hemodynamic characterization using left ventricular pressure-volume analysis.

    PubMed

    Radovits, Tamás; Oláh, Attila; Lux, Árpád; Németh, Balázs Tamás; Hidi, László; Birtalan, Ede; Kellermayer, Dalma; Mátyás, Csaba; Szabó, Gábor; Merkely, Béla

    2013-07-01

    Long-term exercise training is associated with characteristic structural and functional changes of the myocardium, termed athlete's heart. Several research groups investigated exercise training-induced left ventricular (LV) hypertrophy in animal models; however, only sporadic data exist about detailed hemodynamics. We aimed to provide functional characterization of exercise-induced cardiac hypertrophy in a rat model using the in vivo method of LV pressure-volume (P-V) analysis. After inducing LV hypertrophy by swim training, we assessed LV morphometry by echocardiography and performed LV P-V analysis using a pressure-conductance microcatheter to investigate in vivo cardiac function. Echocardiography showed LV hypertrophy (LV mass index: 2.41 ± 0.09 vs. 2.03 ± 0.08 g/kg, P < 0.01), which was confirmed by heart weight data and histomorphometry. Invasive hemodynamic measurements showed unaltered heart rate, arterial pressure, and LV end-diastolic volume along with decreased LV end-systolic volume, thus increased stroke volume and ejection fraction (73.7 ± 0.8 vs. 64.1 ± 1.5%, P < 0.01) in trained versus untrained control rats. The P-V loop-derived sensitive, load-independent contractility indexes, such as slope of end-systolic P-V relationship or preload recruitable stroke work (77.0 ± 6.8 vs. 54.3 ± 4.8 mmHg, P = 0.01) were found to be significantly increased. The observed improvement of ventriculoarterial coupling (0.37 ± 0.02 vs. 0.65 ± 0.08, P < 0.01), along with increased LV stroke work and mechanical efficiency, reflects improved mechanoenergetics of exercise-induced cardiac hypertrophy. Despite the significant hypertrophy, we observed unaltered LV stiffness (slope of end-diastolic P-V relationship: 0.043 ± 0.007 vs. 0.040 ± 0.006 mmHg/μl) and improved LV active relaxation (τ: 10.1 ± 0.6 vs. 11.9 ± 0.2 ms, P < 0.01). According to our knowledge, this is the first study that provides characterization of functional changes and hemodynamic relations in

  19. Similarities of arterial collagen pressure-diameter relationship in ovine femoral arteries and PLLA vascular grafts.

    PubMed

    Armentano, Ricardo L; Cymberknop, Leandro J; Suarez Bagnasco, Diego; Montini Ballarin, Florencia; Balay, Guillermo; Negreira, Carlos A; Abraham, Gustavo A

    2014-01-01

    In-vivo implanted vascular grafts fail due to the mechanical mismatch between the native vessel and the implant. The biomechanical characterization of native vessels provides valuable information towards the development of synthetic grafts. Five samples of electrospun nanofibrous poly(L-lactic acid)(PLLA) tubular structures were subjected to physiological pulsating pressure using an experimental setup. Four ovine femoral arteries were also tested in the experimental setup under the same conditions. Instantaneous diameter and pressure signals were obtained using gold standard techniques, in order to estimate the dynamic pressure-strain elastic modulus (E(Pε)) of both native vessels and grafts. Synthetic grafts showed a significant increase of E(Pε) (10.57±0.97 to 17.63±2.61 10(6) dyn/cm(2)) when pressure was increased from a range of 50-90 mmHg (elastin-response range) to a range of 100-130 mmHg (collagen-response range). Furthermore, femoral arteries also exhibited a significant increase of EPε (1.66±0.30 to 15.76±4.78 10(6) dyn/cm(2)) with the same pressure variation, showing that both native vessels and synthetic grafts have a similar behavior in the collagen-acting range. The mechanical behavior of PLLA vascular grafts was characterized In vitro. However, the procedure can be easily extrapolated to In vivo experiences in conscious and chronically instrumented animals.

  20. Effects of chronic hypoxia on cardiac function measured by pressure-volume catheter in fetal chickens

    PubMed Central

    Giraud, George D.; Espinoza, Herbert M.; Davis, Erica N.; Crossley, Dane A.

    2015-01-01

    Hypoxia is a common component of many developmental insults and has been studied in early-stage chicken development. However, its impact on cardiac function and arterial-ventricular coupling in late-stage chickens is relatively unknown. To test the hypothesis that hypoxic incubation would reduce baseline cardiac function but protect the heart during acute hypoxia in late-stage chickens, white Leghorn eggs were incubated at 21% O2 or 15% O2. At 90% of incubation (19 days), hypoxic incubation caused growth restriction (−20%) and increased the LV-to-body ratio (+41%). Left ventricular (LV) pressure-volume loops were measured in anesthetized chickens in normoxia and acute hypoxia (10% O2). Hypoxic incubation lowered the maximal rate of pressure generation (ΔP/ΔtMax; −22%) and output (−57%), whereas increasing end-systolic elastance (ELV; +31%) and arterial elastance (EA; +122%) at similar heart rates to normoxic incubation. Both hypoxic incubation and acute hypoxia lengthened the half-time of relaxation (τ; +24%). Acute hypoxia reduced heart rate (−8%) and increased end-diastolic pressure (+35%). Hearts were collected for mRNA analysis. Hypoxic incubation was marked by decreased mRNA expression of sarco(endo)plasmic reticulum Ca2+-ATPase 2, Na+/Ca2+ exchanger 1, phospholamban, and ryanodine receptor. In summary, hypoxic incubation reduces LV function in the late-stage chicken by slowing pressure generation and relaxation, which may be driven by altered intracellular excitation-contraction coupling. Cardiac efficiency is greatly reduced after hypoxic incubation. In both incubation groups acute hypoxia reduced diastolic function. PMID:25652537

  1. [Female gender and pulmonary arterial hypertension: a complex relationship].

    PubMed

    Manes, Alessandra; Palazzini, Massimiliano; Dardi, Fabio; D'Adamo, Antonio; Rinaldi, Andrea; Galiè, Nazzareno

    2012-06-01

    Pulmonary arterial hypertension (PAH) is a severe clinical condition defined as mean pulmonary artery pressure ≥25 mmHg and normal pulmonary capillary wedge pressure (≤15 mmHg). In PAH the increase in pulmonary pressure is due to an intrinsic disease of the small pulmonary arteries (resistance vessels) characterized by vascular proliferation and remodeling. The increase in pulmonary vascular resistance with subsequent elevation of the right ventricular afterload leads to right ventricular failure after variable periods of time. Although targeted disease therapies have been developed over the last decade that resulted in improved quality of life and outcome for PAH patients, the prognosis is still severe and there remains no cure for this disease. From a clinical standpoint, PAH includes a group of heterogeneous pathological conditions: in idiopathic, heritable and drug- and toxin-induced PAH, since there are no predisposing clinical conditions, the structural changes in pulmonary circulation are "isolated"; on the other hand, PAH may be associated with some predisposing diseases such as connective tissue disease, HIV infection, portal hypertension, congenital heart disease, schistosomiasis, and chronic hemolytic anemia. PAH can affect individuals of all age groups, and mean age at diagnosis is around 50 years. Epidemiological data show a great preponderance of females in PAH; the high prevalence of females is particularly evident in the so-called "isolated" PAH forms, whereas in PAH associated with other diseases the female:male ratio is strongly influenced by the epidemiological features of the specific predisposing condition. The reason for the higher female prevalence in PAH has never been clarified: some hypotheses involve the role of sexual hormones (estrogens), autoimmunity, or an X-linked locus in disease predisposition. Female gender is not associated with a different clinical presentation. However, the age of onset tends to be earlier in females than

  2. The relationship between obesity and peripheral arterial disease in adult Nigerian diabetics.

    PubMed

    Oyelade, Bolaji Oyelade; Olaolorun, Akintayo D; Odeigah, Louis O; Amole, Isaac O; Aderibigbe, Sunday A

    2014-03-01

    The aim was to identify any relationship between obesity and peripheral arterial disease (PAD) in diabetic subjects. Male and female diabetic subjects aged 50-89 years. Body mass index (BMI) was used to estimate total body weight and the waist-to- hip ratio (WHR) as well as waist circumference (WC) were used for abdominal fat distribution estimation. Peripheral arterial disease was defined by an ankle brachial index <0.9. Peripheral arterial disease (PAD) was observed in 52.5% of the subjects. BMI, WHR and WC did not correlate with PAD. None of the parameters (i.e BMI, WHR and WC) used to assess the relationship between obesity and PAD was found to correlate with PAD.

  3. Genetics of Lipid Traits and Relationship to Coronary Artery Disease

    PubMed Central

    Keenan, Tanya E.; Rader, Daniel J.

    2013-01-01

    Despite the critical importance of plasma lipoproteins in the development of atherosclerosis, varying degrees of evidence surround the causal associations of lipoproteins with coronary artery disease (CAD). These causal contributions can be assessed by employing genetic variants as unbiased proxies for lipid levels. A relatively large number of low-density lipoprotein cholesterol (LDL-C) variants strongly associate with CAD, confirming the causal impact of this lipoprotein on atherosclerosis. Although not as firmly established, genetic evidence supporting a causal role of triglycerides (TG) in CAD is growing. Conversely, high-density lipoprotein cholesterol (HDL-C) variants not associated with LDL-C or TG have not yet been shown to be convincingly associated with CAD, raising questions about the causality of HDL-C in atherosclerosis. Finally, genetic variants at the LPA locus associated with lipoprotein(a) [Lp(a)] are decisively linked to CAD, indicating a causal role for Lp(a). Translational investigation of CAD-associated lipid variants may identify novel regulatory pathways with therapeutic potential to alter CAD risk. PMID:23881580

  4. Relationship between left coronary artery bifurcation angle and restenosis after stenting of the proximal left anterior descending artery

    PubMed Central

    Yamamoto, Tadashi; Funayama, Naohiro; Nishihara, Hiroshi; Hotta, Daisuke

    2016-01-01

    Introduction Restenosis after a percutaneous coronary intervention for proximal left anterior descending (pLAD) coronary artery disease remains a clinical challenge. However, the relationship between the left main trunk (LMT)/LAD bifurcation angle and the pLAD artery restenosis is unclear. This study examined the relationship between the LMT–LAD bifurcation angle and restenosis after stent implantation for pLAD disease. Methods We analysed the data of 177 consecutive patients who underwent stent implantation for pLAD disease, followed by coronary angiography between December 2008 and September 2013. The LMT–LAD bifurcation angle was measured in the left or the right anterior oblique caudal (CAU) angiographic view. Results and discussion Out of 177 patients, 12 developed in-stent restenosis and 21 developed in-segment restenosis. The mean angle in patients with in-stent restenosis (52.2°±14.5°) in the left anterior oblique CAU view was significantly larger than that in patients without restenosis (32.0°±18.1°; P<0.001). The LMT–LAD angle in the right anterior oblique CAU view was significantly larger in patients with in-segment restenosis (27.3°±14.3°) than in patients without restenosis (17.5°±10.1°; P<0.001). Moreover, by multivariate analysis, the LMT–LAD angle was an independent predictor of in-stent and in-segment restenosis, after adjustment for significant confounders such as diabetes, hypertension, dyslipidaemia, final minimum lesion diameter and lesion length. Conclusion This study suggests that a wide LMT–LAD angle is a predictor of restenosis after stent implantation for pLAD artery disease. PMID:27214275

  5. Relationship between plaque development and local hemodynamics in coronary arteries

    NASA Astrophysics Data System (ADS)

    Wahle, Andreas; Lopez, John J.; Olszewski, Mark E.; Vigmostad, Sarah C.; Braddy, Kathleen C.; Brennan, Theresa M. H.; Bokhari, Syed W.; Bennett, J. Gray; Holper, Elizabeth M.; Rossen, James D.; Chandran, Krishnan B.; Sonka, Milan

    2005-04-01

    The mechanisms of plaque development in coronary arteries are not yet completely understood. Vessel geometry influences the local hemodynamics within a vessel, and the resulting wall shear stress in turn influences plaque development. Previously, we showed in-vivo that plaque tends to accumulate more on the inner curvature of a vessel than on its outer curvature. While vessel curvature is preserved during plaque progression, the local wall shear stresses change with lumen narrowing. The aim of this study was to test how the hypothesis that locations of low wall shear stress coincide with circumferentially larger plaque accumulation depends on vascular remodeling with or without lumen narrowing. We have analyzed 39 in-vivo intravascular-ultrasound pullbacks, for which geometrically accurate 3-D models were obtained by fusion with x-ray angiography. Distorting subsegments (branches, calcifications, stents) were discarded, and the relative number of vessel locations was determined within a 10-40% area-stenosis range. This range corresponds to compensatory enlargement (outward or positive vessel remodeling), but not yet lumen narrowing, and these vessel segments were a focus of our study. For each segment, we determined the relative number of vessel locations for which circumferentially low wall shear stress coincided with larger plaque thickness and vice versa. The inverse association between wall shear stress and plaque thickness was significantly more pronounced (p<0.005) in vessel cross sections exhibiting compensatory enlargement without luminal narrowing than when the full spectrum of vessel stenosis severity was considered. Thus, the hypothesis is supported more in subsegments with less developed disease.

  6. Galectin-3 in Peripheral Artery Disease. Relationships with Markers of Oxidative Stress and Inflammation.

    PubMed

    Fort-Gallifa, Isabel; Hernández-Aguilera, Anna; García-Heredia, Anabel; Cabré, Noemí; Luciano-Mateo, Fedra; Simó, Josep M; Martín-Paredero, Vicente; Camps, Jordi; Joven, Jorge

    2017-05-04

    Galectin-3 is a modulator of oxidative stress, inflammation, and fibrogenesis involved in the pathogenesis of vascular diseases. The present study sought to characterize, in patients with peripheral artery disease (PAD), the localization of galectin-3 in arterial tissue, and to analyze the relationships between the circulating levels of galectin-3 and oxidative stress and inflammation. It also sought to compare the diagnostic accuracy of galectin-3 with that of other biochemical markers of this disease. We analyzed femoral or popliteal arteries from 50 PAD patients, and four control arteries. Plasma from 86 patients was compared with that from 72 control subjects. We observed differences in the expression of galectin-3 in normal arteries, and arteries from patients with PAD, with a displacement of the expression from the adventitia to the media, and the intima. In addition, plasma galectin-3 concentration was increased in PAD patients, and correlated with serologic markers of oxidative stress (F2-isoprostanes), and inflammation [chemokine (C-C motif) ligand 2, C-reactive protein, β-2-microglobulin]. We conclude that the determination of galectin-3 has good diagnostic accuracy in the assessment of PAD and compares well with other analytical parameters currently in use.

  7. Relationships between coronary flow vasodilator capacity and small artery remodelling in hypertensive patients.

    PubMed

    Rizzoni, Damiano; Palombo, Carlo; Porteri, Enzo; Muiesan, Maria Lorenza; Kozàkovà, Michaela; La Canna, Giovanni; Nardi, Matilde; Guelfi, Daniele; Salvetti, Massimo; Morizzo, Carmela; Vittone, Francesca; Rosei, Enrico Agabiti

    2003-03-01

    Arterial hypertension is frequently associated with the presence of structural alterations in small arteries. Moreover, a reduced coronary flow reserve and vasodilator capacity has been observed in essential hypertensive patients, possibly due, at least in part, to microangiopathy of small coronary vessels. The aim of the present study was to evaluate a possible relationship between subcutaneous small artery structure and coronary flow reserve or vasodilator capacity in patients with essential hypertension. A total of 20 patients with mild to moderate essential hypertension were included in the study, and underwent a biopsy of the subcutaneous fat from the gluteal region. Small arteries were dissected and mounted on a micromyograph. The media thickness, the normalized internal diameter and the media:lumen ratio (M/L) were then calculated. In addition, a transesophageal Doppler echocardiographic study, which allows the measurement of coronary flow velocity before and during maximal pharmacological vasodilatation, was performed. Coronary flow reserve (CFR) was measured as the ratio of coronary flow velocity assessed during adenosine infusion and that measured in basal conditions. From blood pressure and coronary flow velocity during adenosine infusion, minimum coronary resistance was calculated. CFR as well as minimum coronary resistance were significantly correlated to both M/L and to normalized internal diameter of subcutaneous small arteries. Our results are consistent with the hypothesis of a generalized remodelling of small arteries in the body, including the coronary circulation; this remodelling may play an important role in the reduction of coronary vasodilator capacity in patients with mild to moderate essential hypertension.

  8. Non-Invasive Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume

    DTIC Science & Technology

    2002-10-01

    Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume PRINCIPAL INVESTIGATOR: Aloyzas Petrikas, Ph.D. Arminas Ragauskas Gediminas...Ultrasonic Diagnosing and Monitoring of DAMD17-00-2-0065 Intracranial Pressure/Volume 6. AUTHOR(S) Aloyzas Petrikas, Ph.D. Arminas Ragauskas Gediminas...Objectives were to verify the innovative concepts of non-invasive intracranial pressure (ICP) absolute value measurement and non- invasive

  9. Relationship between sleep duration and arterial stiffness in a multi-ethnic population: The HELIUS study

    PubMed Central

    Anujuo, Kenneth; Stronks, Karien; Snijder, Marieke B.; Jean-Louis, Girardin; van den Born, Bert-Jan; Peters, Ron J.; Agyemang, Charles

    2017-01-01

    We examined the relationship between sleep duration and arterial stiffness among a multi-ethnic cohort, and whether the associations differed among ethnic minority groups in the Netherlands. Data were derived from 10 994 participants (aged 18–71 years) of the Healthy Life in an Urban Setting (HELIUS) study. Self-reported sleep duration was categorized into: short (<7 h/night), healthy (7–8 h/night) and long (≥9 h/night). Arterial stiffness was assessed by duplicate pulse-wave velocity (PWV in m/s) measurements using the Arteriograph system. The association of sleep duration with PWV was analysed using linear regression (β) with 95% confidence interval (CI). Results showed that neither short nor long sleep was related to PWV in all ethnic groups, except for long sleep in Dutch men which was associated with higher PWV (indicating stiffer arteries) after adjustment for potential confounders (β = 0.67, 95%CI, 0.23–1.11). Our study showed no convincing evidence that sleep duration was related to arterial stiffness among various ethnic groups. The link between sleep duration and cardiovascular outcomes does not seem to operate through arterial stiffness. Further research is needed to consolidate these findings. PMID:27058653

  10. Non-invasive measurements of arterial compliance in hypertensive compared with normotensive adults.

    PubMed

    Roman, M J; Pini, R; Pickering, T G; Devereux, R B

    1992-08-01

    To determine differences in arterial compliance attributable to hypertension. Since measurements of arterial compliance have tended to vary in the past according to the method used, a new technique comprising carotid ultrasound and simultaneous, calibrated, carotid pressure waveform measurements was tested in 43 hypertensives and 43 control subjects matched for age, gender and body size. There was a significant reduction in compliance among the hypertensive patients, as estimated by the elastic modulus and the ratio of stroke volume to pulse pressure. However, when the non-linearity of the pressure-volume relationship and the impact of distending pressure were taken into account, by the arterial stiffness index and by the increase in arterial wall thickness associated with hypertension by Young's modulus, there were no significant differences in arterial compliance between the two groups.

  11. Putative role for apelin in pressure/volume homeostasis and cardiovascular disease.

    PubMed

    Charles, Christopher J

    2007-01-01

    Apelin is a peptide recently isolated from bovine stomach extracts which appears to act as an endogenous ligand for the previously orphaned G-protein-coupled APJ receptor. The apelin gene encodes for a pre-propeptide consisting of 77 amino acids with mature apelin likely to be derived from the C-terminal region as either a 36, 17 or 13 amino acid peptide. Apelin mRNA expression and peptide immunoreactivity has been described in a variety of tissues including gastrointestinal tract, adipose tissue, brain, kidney, liver, lung and at various sites within the cardiovascular system. Apelin is strongly expressed in the heart with expression also present in the large conduit vessels, coronary vessels and endothelial cells. Message expression for the APJ receptor is similarly distributed throughout the brain and periphery, again including cardiovascular tissue. Consistent with this pattern of distribution, apelin and APJ have been shown to exhibit some role in the regulation of fluid homeostasis. In addition, a growing number of studies have reported cardiovascular actions of apelin. Not only has apelin been observed to alter arterial pressure, but the peptide also exhibits endothelium-dependent vasodilator actions in vivo and positive inotropic actions in the isolated heart. Furthermore, differences in apelin and APJ expression have been described in patients with congestive heart failure and circulating levels of apelin are also reported to change in heart failure. Taken together, these studies suggest a role for apelin in pressure/volume homeostasis and in the pathophysiology of cardiovascular disease. As such, manipulation of this peptide system may offer benefit to the syndrome of heart failure with potential clinical applications in humans.

  12. Inverse relationship between physical activity and arterial stiffness in adults with hypertension.

    PubMed

    O'Donovan, Cuisle; Lithander, Fiona E; Raftery, Tara; Gormley, John; Mahmud, Azra; Hussey, Juliette

    2014-02-01

    Physical activity has beneficial effects on arterial stiffness among healthy adults. There is a lack of data on this relationship in adults with hypertension. The majority of studies which have examined physical activity and arterial stiffness have used subjective measures of activity. The aim of this study was to investigate the relationship between objectively measured habitual physical activity and arterial stiffness in individuals with newly diagnosed essential hypertension. Adults attending an outpatient hypertension clinic were recruited into this cross sectional study. Physical activity was measured using a triaxial accelerometer. Pulse wave velocity (PWV) and augmentation index (AIx) were measured using applanation tonometry. Participant's full lipid profile and glucose were determined through the collection of a fasting blood sample. Fifty-three adults [51(14) years, 26 male] participated, 16 of whom had the metabolic syndrome. Inactivity was positively correlated with PWV (r = .53, P < .001) and AIx (r = .48, P < .001). There were significant inverse associations between habitual physical activity of all intensities and both AIx and PWV. In stepwise regression, after adjusting for potential confounders, physical activity was a significant predictor of AIx and PWV. Habitual physical activity of all intensities is associated with reduced arterial stiffness among adults with hypertension.

  13. Arterial supply to the thyroid gland and the relationship between the recurrent laryngeal nerve and the inferior thyroid artery in human fetal cadavers.

    PubMed

    Ozgüner, G; Sulak, O

    2014-11-01

    The aim of this study was to identify the arterial supply to the thyroid gland and the relationship between the inferior thyroid artery (ITA) and the recurrent laryngeal nerve (RLN) in fetal cadavers using anatomical dissection. The anterior necks of 200 fetuses were dissected. The origins of the superior thyroid artery (STA) and the ITA and location of the ITA in relation to the entrance of the thyroid lobe were examined. The relationship between the ITA and the RLN was determined. The origins of the STA were classified as: external carotid artery, common carotid artery (CCA), and the thyrolingual trunk. The origins of the ITA were the thyrocervical trunk and the CCA. The ITA was absent on the left side in two cases. The relationship of the RLN to the ITA fell into seven different types. Type 1: the RLN lay posterior to the artery; right (42.5%), left (65%). Type 2: the RLN lay anterior to the artery; right (40.5%), left (22.5%). Type 3: the RLN lay parallel to the artery; right (11.5%), left (7%). Type 4: the RLN lay between the two branches of the artery; right (1%), left (3.5%). Type 5: The extralaryngeal branch of the RLN was detected before it crossed the ITA; right (4.5%), left (0%). Type 6: the ITA lay between the two branches of the RLN; right (0%), left (0.5%). Type 7: the branches of the RLN lay among the branches of the ITA; right (0%), left (0.5%). The results from this study would be useful in future thyroid surgeries. © 2014 Wiley Periodicals, Inc.

  14. Non-invasive method and apparatus for monitoring intracranial pressure and pressure volume index in humans

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    1997-01-01

    Non-invasive measuring devices responsive to changes in a patient's intracranial pressure (ICP) can be accurately calibrated for monitoring purposes by providing known changes in ICP by non-invasive methods, such as placing the patient on a tilting bed and calculating a change in ICP from the tilt angle and the length of the patient's cerebrospinal column, or by placing a pressurized skull cap on the patient and measuring the inflation pressure. Absolute values for the patient's pressure-volume index (PVI) and the steady state ICP can then be determined by inducing two known changes in the volume of cerebrospinal fluid while recording the corresponding changes in ICP by means of the calibrated measuring device. The two pairs of data for pressure change and volume change are entered into an equation developed from an equation describing the relationship between ICP and cerebrospinal fluid volume. PVI and steady state ICP are then determined by solving the equation. Methods for inducing known changes in cerebrospinal fluid volume are described.

  15. Non-invasive method and apparatus for monitoring intracranial pressure and pressure volume index in humans

    NASA Technical Reports Server (NTRS)

    Cantrell, John H. (Inventor); Yost, William T. (Inventor)

    1994-01-01

    Non-invasive measuring devices responsive to changes in a patient's intracranial pressure (ICP) can be accurately calibrated for monitoring purposes by providing known changes in ICP by non-invasive methods, such as placing the patient on a tilting bed and calculating a change in ICP from the tilt angle and the length of the patient's cerebrospinal column, or by placing a pressurized skull cap on the patient and measuring the inflation pressure. Absolute values for the patient's pressure-volume index (PVI) and the steady state ICP can then be determined by inducing two known changes in the volume of cerebrospinal fluid while recording the corresponding changes in ICP by means of the calibrated measuring device. The two pairs of data for pressure change and volume change are entered into an equation developed from an equation describing the relationship between ICP and cerebrospinal fluid volume. PVI and steady state ICP are then determined by solving the equation. Methods for inducing known changes in cerebrospinal fluid volume are described.

  16. Entropy Production and the Pressure-Volume Curve of the Lung.

    PubMed

    Oliveira, Cláudio L N; Araújo, Ascânio D; Bates, Jason H T; Andrade, José S; Suki, Béla

    2016-01-01

    We investigate analytically the production of entropy during a breathing cycle in healthy and diseased lungs. First, we calculate entropy production in healthy lungs by applying the laws of thermodynamics to the well-known transpulmonary pressure-volume (P-V) curves of the lung under the assumption that lung tissue behaves as an entropic spring similar to rubber. The bulk modulus, B, of the lung is also derived from these calculations. Second, we extend this approach to elastic recoil disorders of the lung such as occur in pulmonary fibrosis and emphysema. These diseases are characterized by particular alterations in the P-V relationship. For example, in fibrotic lungs B increases monotonically with disease progression, while in emphysema the opposite occurs. These diseases can thus be mimicked simply by making appropriate adjustments to the parameters of the P-V curve. Using Clausius's formalism, we show that entropy production, ΔS, is related to the hysteresis area, ΔA, enclosed by the P-V curve during a breathing cycle, namely, ΔS=ΔA∕T, where T is the body temperature. Although ΔA is highly dependent on the disease, such formula applies to healthy as well as diseased lungs, regardless of the disease stage. Finally, we use an ansatz to predict analytically the entropy produced by the fibrotic and emphysematous lungs.

  17. Relationship between arterial and venous Doppler and perinatal outcome in fetal growth restriction.

    PubMed

    Baschat, A A; Gembruch, U; Reiss, I; Gortner, L; Weiner, C P; Harman, C R

    2000-10-01

    The aim of this investigation was to assess the relationship between abnormal arterial and venous Doppler findings and perinatal outcome in fetuses with intrauterine growth restriction (IUGR). Doppler velocimetry of the umbilical artery (UA), middle cerebral artery (MCA), inferior vena cava (IVC), ductus venosus (DV) and free umbilical vein was performed in 121 IUGR fetuses with a UA pulsatility index (PI) > 2 SD above the gestational age mean and subsequent birth weight < 10th centile for gestational age. Groups based on the last Doppler exam were: 1 = abnormal UA-PI only (n = 42, 34.7%), 2 = MCA-PI > 2 SD below the gestational age mean (= 'brain sparing') in addition to abnormal UA-PI (n = 29, 24.0%), 3 = DV or IVC peak velocity index (PVIV) > 2 SD above the gestational age mean and/or pulsatile UV flow (n = 50, 41.3%). Z-scores (delta indices) were calculated for Doppler indices. Perinatal mortality, respiratory distress (RDS), bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), circulatory failure and umbilical artery blood gases were recorded. Absence or reversal of umbilical artery end-diastolic flow was observed in 4 (9.5%) of fetuses in group 1, 10 (34.5%) fetuses in group 2 and 41 (82%) fetuses in group 3. A low middle cerebral artery pulsatility index was found in 39 (78%) fetuses in group 3. Multiple regression analysis with gestational age at delivery, delta indices and cord artery blood gas as independent parameters and individual perinatal outcomes as dependent variables was performed. In this analysis the association was strongest with gestational age for each complication. There were no significant differences in Apgar scores between groups. At delivery, 'brain sparing' was associated with hypoxemia and abnormal venous flows with acidemia. Perinatal mortality was highest in group 3 and stillbirth was only observed when venous flow was abnormal. All postpartum complications were more frequent in

  18. The red cell mass-arterial oxygen relationship in normal man

    PubMed Central

    Weil, John V.; Jamieson, Gail; Brown, Donald W.; Grover, Robert F.

    1968-01-01

    The normal relationship between red cell mass measured, with 51chromium-labeled red cells, and arterial oxygen saturation (SaO2) over the range from 97.3 to 83.4% was examined by studying 73 normal men residing at sea level and altitudes of 1600 and 3100 m. A simple, linear relationship between SaO2 and red cell mass was found over the entire range (r = - 0.7524, P < 0.001). In contrast, a correlation between red cell mass and arterial O2 tension was found only over the lower half of the range of O2 tensions where SaO2 was also decreased (r = - 0.7731, P < 0.005). This suggested that O2 saturation rather than tension is the more important determinant of the erythropoietic response to chronic hypoxia. If this response is regulated by tissue O2 tension, then it will be influenced by O2 transport, which, in turn, is a function of blood flow and arterial O2 content, and hence SaO2. In nine patients with chronic obstructive airway disease the relationship between red cell mass and SaO2 was also determined and was found to be steeper than in the normal subjects (P < 0.05). Images PMID:5658592

  19. Length-tension relationships of small arteries, veins, and lymphatics from the rat mesenteric microcirculation.

    PubMed

    Zhang, Rong-Zhen; Gashev, Anatoliy A; Zawieja, David C; Davis, Michael J

    2007-04-01

    The passive and active length-tension relationships of isolated rat mesenteric lymphatics ( approximately 150 microm ID), and adjacent small arteries ( approximately 240 microm) and veins ( approximately 275 microm) were compared under isometric conditions using a wire myograph. About 60% of the lymphatic vessels developed spontaneous contractions in physiological saline solution at nominal preload. To maximally activate smooth muscle, 145 mM K(+) + 5 x 10(-5) M norepinephrine was used for arteries, and 145 mM K(+) + 1 x 10(-6) M substance P was used for lymphatics and veins. In response, arteries exhibited monotonic force development to a plateau level, whereas lymphatics and veins showed biphasic force development, consisting of a transient force peak followed by partial relaxation to a plateau over approximately 5 min. The passive and the active length-tension curves were similar in shape among all three vessels. However, the maximal active tension of arteries (3.4 +/- 0.42 mN/mm) was significantly greater than peak active tension (0.59 +/- 0.04 mN/mm) or plateau tension (0.20 +/- 0.04 mN/mm) in small veins and greater than peak active tension (0.34 +/- 0.02 mN/mm) or plateau tension (0.21 +/- 0.02 mN/mm) in lymphatics. Maximal active medial wall stress was similar between lymphatics and veins but was approximately fivefold higher in small arteries. For lymphatics, the pressure calculated from the optimal preload was significantly higher than that found previously in isobaric studies of isolated lymphatics, suggesting the capacity to operate at higher than normal pressures for increased responsiveness. Our results represent the first mechanical comparisons of arterial, venous, and lymphatic vessels in the same vasculature.

  20. Relationship between sympathetic baroreflex sensitivity and arterial stiffness in elderly men and women.

    PubMed

    Okada, Yoshiyuki; Galbreath, M Melyn; Shibata, Shigeki; Jarvis, Sara S; VanGundy, Tiffany B; Meier, Rhonda L; Vongpatanasin, Wanpen; Levine, Benjamin D; Fu, Qi

    2012-01-01

    Previous human studies have shown that large-artery stiffness contributes to an age-related decrease in cardiovagal baroreflex sensitivity. Whether this is also true with sympathetic baroreflex sensitivity is unknown. We tested the hypothesis that sympathetic baroreflex sensitivity is associated with the stiffness of baroreceptor segments (the carotid artery and the aorta) in elderly individuals and that sex affects this relationship. Sympathetic baroreflex sensitivity was assessed from the spontaneous changes in beat-by-beat diastolic pressure and corresponding muscle sympathetic nerve activity (microneurography) during supine rest in 30 men (mean±SEM: 69±1 years) and 31 women (68±1 years). Carotid artery stiffness (B-mode ultrasonography) and aortic stiffness (MRI) were also determined. We found that elderly women had lower sympathetic baroreflex sensitivity than elderly men (-2.33±0.25 versus -3.32±0.25 bursts · 100 beats(-1) · mm Hg(-1); P=0.007). β-Stiffness indices of the carotid artery and the aorta were greater in elderly women than in men (6.68±0.48 versus 5.10±0.50 and 4.03±0.47 versus 2.68±0.42; both P<0.050). Sympathetic baroreflex sensitivity was inversely correlated with carotid artery stiffness in both men and women (r=0.49 and 0.50; both P<0.05), whereas this relation was shifted in parallel upward (toward a reduced sensitivity) in women with no changes in the slope (0.26 versus 0.24 arbitrary units). Sympathetic baroreflex sensitivity and aortic stiffness showed similar trends. Thus, barosensory artery stiffness seems to be one independent determinant of sympathetic baroreflex sensitivity in elderly men and women. The lower sympathetic baroreflex sensitivity in elderly women may predispose them to an increased prevalence of hypertension.

  1. Relationships between central arterial stiffness, lean body mass, and absolute and relative strength in young and older men and women.

    PubMed

    Fahs, Christopher A; Thiebaud, Robert S; Rossow, Lindy M; Loenneke, Jeremy P; Bemben, Debra A; Bemben, Michael G

    2017-08-16

    Relationships between muscular strength and arterial stiffness as well as between muscle mass and arterial stiffness have been observed suggesting a link between the neuromuscular system and vascular health. However, the relationship between central arterial stiffness and absolute and relative strength along with muscle mass has not been investigated in both sexes across a broad age range. The purpose of this study was to examine the relationship between central arterial stiffness and absolute and relative strength as well as between central arterial stiffness and lean body mass (LBM) in men and women across a broad age range. LBM, central arterial stiffness and strength were measured on 36 men and 35 women between the ages of 18 and 75 years. Strength was measured on five machine resistance exercises and summed as one measure of overall strength (absolute strength). Relative strength was calculated as total strength divided by LBM (relative strength). Central arterial stiffness was inversely related to both absolute (r = -0·230; P = 0·029) and relative strength (r = -0·484; P < 0·001) but not LBM (r = 0·097; P = 0·213). The relationship between central arterial stiffness and relative strength was attenuated but still present when controlling for either age, per cent body fat, LBM or mean arterial pressure. These results suggest that, across a wide age range, the expression of relative muscular strength has a stronger relationship with central arterial stiffness compared to either LBM or absolute strength. This suggests that muscle function more than muscle mass may be coupled with vascular health. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  2. Relationships between urinary electrolytes excretion and central hemodynamics, and arterial stiffness in hypertensive patients.

    PubMed

    Han, Weizhong; Han, Xiao; Sun, Ningling; Chen, Yunchao; Jiang, Shiliang; Li, Min

    2017-08-01

    High sodium intake plays an important role in the onset and exacerbation of hypertension. However, the relationships between urinary electrolytes excretion and central hemodynamics and between urinary electrolyte excretion and arterial stiffness are still the subject of debate. This study sought to clarify the associations of salt intake with central aortic pressure and arterial stiffness indicators. A total of 431 untreated hypertensive individuals were recruited into the study. Twenty-four-hour urinary samples were collected to measure the excretion of urinary electrolytes. Central hemodynamics parameters and brachial-ankle pulse wave velocity (baPWV) were measured. We evaluated the independent relationship between urinary sodium or potassium excretion and the abovementioned indices. The mean 24-h urinary sodium of all subjects was 166.6±70.0 mmol/24 h. With increases in urinary sodium excretion, central blood pressure and baPWV values markedly increased. Multiple regression analysis showed that urinary sodium was independently associated with increases in central systolic blood pressure, central diastolic blood pressure, the augmentation index, and baPWV. Significant correlations were identified between high dietary sodium and central hemodynamics and between high dietary sodium and arterial elasticity. Prospective interventional studies in hypertensive patients may be required to determine the effect of salt intake on central hemodynamics.

  3. Relationship between left ventricular diastolic function and arterial stiffness in asymptomatic patients with diabetes mellitus.

    PubMed

    Roos, Cornelis J; Auger, Dominique; Djaberi, Roxana; de Koning, Eelco J; Rabelink, Ton J; Pereira, Alberto M; Bax, Jeroen J; Delgado, Victoria; Jukema, J Wouter; Scholte, Arthur J

    2013-03-01

    Left ventricular (LV) diastolic dysfunction and increased arterial stiffness are common in patients with diabetes mellitus (DM). However, the relation between these two pathophysiological factors remains unclear. The aim of this study was to investigate the relationship between LV diastolic function and arterial stiffness as assessed with applanation tonometry. In 142 asymptomatic patients with DM (mean age 48 years, 75 (53 %) men, 72 (51 %) patients with type 2 DM) LV diastolic function was assessed with echocardiography. Arterial stiffness was evaluated measuring the aortic pulse wave velocity (PWV) whereas wave reflection was assessed measuring central systolic blood pressure (cSBP), central pulse pressure (cPP), and augmentation index (AIx) with applanation tonometry. Mean E/A ratio, E' and E/E' ratio were 1.1 ± 0.3, 8.1 ± 2.3 and 9.2 ± 3.3 cm/s, respectively. Mean PWV, mean cSBP, median cPP and mean AIx were 7.9 ± 2.4 m/s, 122 ± 17 mmHg, 40 [35-51] mmHg and 17.9 ± 12.1 %, respectively. PWV was independently associated with LV diastolic dysfunction grade (β = 0.76, p = 0.03). In contrast, measures of wave reflection, cPP, cSBP and AIx were independently related with E/A ratio, but not with the LV diastolic dysfunction grade. Parameters of arterial stiffness and wave reflection are associated with echocardiographic indices of LV diastolic function in asymptomatic patients with DM. Therapies that prevent progression of arterial stiffness and reduce late-systolic pressure overload may help to reduce the prevalence of LV diastolic dysfunction in this population.

  4. The relationship of myocardial bridges to coronary artery dominance in the adult human heart.

    PubMed

    Loukas, Marios; Curry, Brian; Bowers, Maggi; Louis, Robert G; Bartczak, Artur; Kiedrowski, Miroslaw; Kamionek, Michal; Fudalej, Martin; Wagner, Teresa

    2006-07-01

    Myocardial bridging is recognized as an anatomical variation of the human coronary circulation in which an epicardial artery lies in the myocardium for part of its course. Thus, the vessel is 'bridged' by myocardium. The anterior interventricular branch of the left coronary artery has been reported as the most common site of myocardial bridges but other locations have been reported. The purpose of this study was to provide more definitive information on the vessels with myocardial bridges, the length and depth of the bridged segment, and the relationship between the presence of bridges and coronary dominance. Two hundred formalin-fixed human hearts were examined. Myocardial bridges were found in 69 (34.5%) of the hearts with a total of 81 bridges. One bridge was found in 59 of these hearts and multiple bridges were observed in ten (eight with double bridges and two with triple bridges). Bridges were most often found over the anterior interventricular artery (35 hearts). Bridges were also found over the diagonal branch of the left coronary artery (14), over the left marginal branch (five) and over the inferior interventricular branch of the left coronary artery (six). Bridges were also found over the right coronary artery (15 hearts), over the right marginal branch (four) and over the inferior interventricular branch of the right coronary artery (two). The presence of bridges appeared to be related to coronary dominance, especially in the left coronary circulation. Forty-six (66.6%) of the hearts with bridges were left dominant. Forty-two of these had bridges over the left coronary circulation and four over the right coronary circulation. Seventeen hearts (24.6%) were right dominant. Eleven of these had bridges over the right coronary circulation and six over the left coronary circulation. The remaining six hearts were co-dominant with four having bridges over the left coronary circulation and two over the right coronary circulation. The mean length of the bridges

  5. Cardiac output assessment using oxygen consumption estimated from the left ventricular pressure-volume area.

    PubMed

    Negroni, Jorge A; Lascano, Elena C; Bertolotti, Alejandro M; Gómez, Carmen B; Rodríguez Correa, Carlos A; Favaloro, Roberto R

    2010-01-01

    Use of a majority of structural variables (age, sex, height) to estimate oxygen consumption in the calculation of cardiac output (CO) by the Fick principle does not account for changes in physiological conditions. To improve this limitation, oxygen consumption was estimated based on the left ventricular pressure-volume area. A pilot study with 10 patients undergoing right cardiac catheterization showed that this approach was successful to estimate CO (r=0,73, vs. thermodilution measured CO). Further essays changing end-diastolic-volume in the pressure-volume area formula by body weight or body surface area showed that this last yielded the best correlation with the thermodilution measured CO (slope=1, ordinate =0.01 and r=0.93). These preliminary results indicate that use of a formula originated from the pressure-volume-area concept is a good alternative to estimate oxygen consumption for CO calculation.

  6. Characterization of the Branching Structure of the Lung from ''Macroscopic'' Pressure-Volume Measurements

    SciTech Connect

    Majumdar, A.; Alencar, A. M.; Buldyrev, S. V.; Hantos, Z.; Stanley, H. E.; Suki, B.

    2001-07-30

    We analyze the problem of fluid flow in a bifurcating structure containing random blockages that can be removed by fluid pressure. We introduce an asymmetric tree model and find that the predicted pressure-volume relation is connected to the distribution {Pi}(n) of the generation number n of the tree's terminal segments. We use this relation to explore the branching structure of the lung by analyzing experimental pressure-volume data from dog lungs. The {Pi}(n) extracted from the data using the model agrees well with experimental data on the branching structure. We can thus obtain information about the asymmetric structure of the lung from macroscopic, noninvasive pressure-volume measurements.

  7. A study on the relationship between intraglandular arterial distribution and thyroid lobe shape: implications for biotechnology of a bioartificial thyroid.

    PubMed

    Toni, Roberto; Casa, Claudia Della; Bodria, Monica; Spaletta, Giulia; Vella, Rocco; Castorina, Sergio; Gatto, Andrea; Teti, Gabriella; Falconi, Mirella; Rago, Teresa; Vitti, Paolo; Sgallari, Fiorella

    2008-11-20

    We have recently hypothesized that structural and secretory components of the adult human thyroid gland maintain constant reciprocal and geometrical relationships, even if changes occur in the three-dimensional (3D) architecture of any of these elements. This means that thyroid morphology could be studied from the point of view of a 3D topology. As a consequence, we have investigated anatomical aspects that could support this assumption. In the present study, we show that the presence of a constant relationship can be demonstrated between the vascular arrangement of the gland, including the extension of intraglandular arterial fields, arterial anastomoses and arterial calibers, and the shape as well as volume of the thyroid. Specifically, a statistically significant difference has been found between the network amplitudes of the superior and inferior thyroid arteries in relation to either a conic or an ellipsoidal geometry of the thyroid lobe. In addition, a direct relationship has been implicated between the distribution of arterial anastomoses and the behavior of the lobe as a single hemodynamic unit. Finally, a statistically significant correlation has been observed between average arterial caliber of the inferior thyroid artery and thyroid volume. On the basis of these results, we propose a model of architectural assembly between stromal and parenchymal elements of the adult thyroid that might prove useful in designing a bioartificial gland ex situ. Potential clinical applications of this principle in regenerative medicine of other endocrine organs are highlighted.

  8. Investigation of the relationship between arterial stiffness and sleep architecture in patients with essential hypertension.

    PubMed

    Liao, Hang; Zhao, Liming; Liu, Kai; Chen, Xiaoping

    2016-01-01

    A change in sleep architecture might increase the risk of hypertension and worsen target organs. This study thus aimed to study the features of sleep architecture and examine its relationship with pulse wave velocity (PWV), a measure of arterial stiffness, in patients with essential hypertension and healthy people aged 45-65 years (n = 106). We collected data on demographics, the serum index, overnight polysomnography, vascular testing and ambulatory blood pressure in addition to measuring arterial stiffness and monitoring sleep respiration. We found that patients with hypertension had longer sleep latency and shorter duration. Their sleep efficiency and the ratio of N3 in non-rapid eye movement (NREM) and rapid eye movement were lower, while the micro-arousal index (MI), N1 and N2 in NREM, and the apnea-hypopnea index were higher than normal people in controls. PWV raised with a decrease in N3 and an increase in the MI. In summary, there were notable changes in sleep architecture and with a decrease in N3 and increase in MI can accelerate arterial stiffness and then worsen target organ damage in patients with hypertension.

  9. Quality of traffic flow on urban arterial streets and its relationship with safety.

    PubMed

    Dixit, Vinayak V; Pande, Anurag; Abdel-Aty, Mohamed; Das, Abhishek; Radwan, Essam

    2011-09-01

    The two-fluid model for vehicular traffic flow explains the traffic on arterials as a mix of stopped and running vehicles. It describes the relationship between the vehicles' running speed and the fraction of running vehicles. The two parameters of the model essentially represent 'free flow' travel time and level of interaction among vehicles, and may be used to evaluate urban roadway networks and urban corridors with partially limited access. These parameters are influenced by not only the roadway characteristics but also by behavioral aspects of driver population, e.g., aggressiveness. Two-fluid models are estimated for eight arterial corridors in Orlando, FL for this study. The parameters of the two-fluid model were used to evaluate corridor level operations and the correlations of these parameters' with rates of crashes having different types/severity. Significant correlations were found between two-fluid parameters and rear-end and angle crash rates. Rate of severe crashes was also found to be significantly correlated with the model parameter signifying inter-vehicle interactions. While there is need for further analysis, the findings suggest that the two-fluid model parameters may have potential as surrogate measures for traffic safety on urban arterial streets.

  10. Age-related changes of elements in thoracic and abdominal aortas and coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries and relationships in elements among their arteries.

    PubMed

    Ongkana, Nutcharin; Tohno, Setsuko; Payo, Iria Maria Prieto; Azuma, Cho; Moriwake, Yumi; Minami, Takeshi; Tohno, Yoshiyuki

    2007-01-01

    To elucidate whether the accumulation of elements occurred simultaneously in the various arteries with aging, the authors investigated age-related changes of elements in the eight arteries, such as the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries, and the relationships in the element contents among their arteries. After ordinary dissection by medical students was finished, the thoracic and abdominal aortas and the coronary, common carotid, pulmonary, splenic, common iliac, and uterine arteries were resected from the subjects, who ranged in age from 58 to 94 yr. The element contents were analyzed by inductively coupled plasma-atomic emission spectrometry. It was found that the accumulation of Ca was the highest in the common iliac artery and decreased in the order of the uterine artery, abdominal aorta, coronary artery, thoracic aorta, splenic artery, common carotid artery, and pulmonary artery. Regarding the relationships in the element contents among the eight arteries, it was found that there were significant direct correlations in the contents of Ca, P, Mg, Zn, Fe, and Na between the coronary and splenic arteries, and there were significant correlations in the contents of Ca, P, and Mg between the abdominal aorta and pulmonary artery.

  11. Are there any relationships between umbilical artery Pulsatility Index and macrosomia in fetuses of type I diabetic mothers?

    PubMed

    Maruotti, G M; Rizzo, G; Sirico, A; Sarno, L; Cirigliano, L; Arduini, D; Martinelli, P

    2014-11-01

    To establish whether there are relationships between umbilical artery Pulsatility Index (PI) and fetal macrosomia in pregnancies complicated by type I diabetes. In a retrospective observational study, 102 singleton pregnant women with type I diabetes were considered. Umbilical artery PI was measured by Doppler ultrasonography within one week from delivery and related to neonatal weight. Pregnancies were grouped according to birtweight in macrosomic group (≥4000 g) and normal growth group (<4000 g). Relationships between umbilical artery PI and birth weight and birth weight centile were tested by Pearson's correlation analysis. Further umbilical artery PI values were compared between macrosomic and normally grown fetuses. Birth weight was ≥4000 g in 24 pregnancies (23.5%). A significant relationship was found between umbilical artery PI and neonatal weight (r = 0.512; p < 0.01) and neonatal weight centile (r = 0.400; p < 0.01). Umbilical artery PI were significantly lower (t = -6.013; p < 0.001) in the macrosomic group (0.78; 95% confidence interval (CI) 0.73-0.84) than in the normal growth group (1.00; 95% CI 0.97-1.04). In pregnancies complicated by type I diabetes there is a significant relationship between umbilical artery PI value before delivery and absolute birth weight and birth weight centile. Macrosomic fetuses show a significant reduction in umbilical artery PI when compared with diabetic pregnancies without fetal overgrowth.

  12. Relationship of Albuminuria and Renal Artery Stent Outcomes: Results From the CORAL Randomized Clinical Trial (Cardiovascular Outcomes With Renal Artery Lesions).

    PubMed

    Murphy, Timothy P; Cooper, Christopher J; Pencina, Karol M; D'Agostino, Ralph; Massaro, Joseph; Cutlip, Donald E; Jamerson, Kenneth; Matsumoto, Alan H; Henrich, William; Shapiro, Joseph I; Tuttle, Katherine R; Cohen, David J; Steffes, Michael; Gao, Qi; Metzger, D Christopher; Abernethy, William B; Textor, Stephen C; Briguglio, John; Hirsch, Alan T; Tobe, Sheldon; Dworkin, Lance D

    2016-11-01

    Randomized clinical trials have not shown an additional clinical benefit of renal artery stent placement over optimal medical therapy alone. However, studies of renal artery stent placement have not examined the relationship of albuminuria and treatment group outcomes. The CORAL study (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) is a prospective clinical trial of 947 participants with atherosclerotic renal artery stenosis randomized to optimal medical therapy with or without renal artery stent which showed no treatment differences (3(5.8% and 35.1% event rate at mean 43-month follow-up). In a post hoc analysis, the study population was stratified by the median baseline urine albumin/creatinine ratio (n=826) and analyzed for the 5-year incidence of the primary end point (myocardial infarction, hospitalization for congestive heart failure, stroke, renal replacement therapy, progressive renal insufficiency, or cardiovascular disease- or kidney disease-related death), for each component of the primary end point, and overall survival. When baseline urine albumin/creatinine ratio was ≤ median (22.5 mg/g, n=413), renal artery stenting was associated with significantly better event-free survival from the primary composite end point (73% versus 59% at 5 years; P=0.02), cardiovascular disease-related death (93% versus 85%; P≤ 0.01), progressive renal insufficiency (91% versus 77%; P=0.03), and overall survival (89% versus 76%; P≤0.01), but not when baseline urine albumin/creatinine ratio was greater than median (n=413). These data suggest that low albuminuria may indicate a potentially large subgroup of those with renal artery stenosis that could experience improved event-free and overall-survival after renal artery stent placement plus optimal medical therapy compared with optimal medical therapy alone. Further research is needed to confirm these preliminary observations.

  13. Bio-telemetric device for measurement of left ventricular pressure-volume loops using the admittance technique in conscious, ambulatory rats

    PubMed Central

    Raghavan, Karthik; Feldman, Marc D; Porterfield, John E; Larson, Erik R; Jenkins, J Travis; Escobedo, Daniel; Pearce, John A

    2011-01-01

    This paper presents the design, construction and testing of a device to measure pressure volume loops in the left ventricle of conscious, ambulatory rats. Pressure is measured with a standard sensor, but volume is derived from data collected from a tetrapolar electrode catheter using a novel admittance technique. There are two main advantages of the admittance technique to measure volume. First, the contribution from the adjacent muscle can be instantaneously removed. Second, the admittance technique incorporates the nonlinear relationship between the electric field generated by the catheter and the blood volume. A low power instrument weighing 27 g was designed, which takes pressure-volume loops every 2 minutes and runs for 24 hours. Pressure-volume data are transmitted wirelessly to a base station. The device was first validated in thirteen rats with an acute preparation with 2-D echocardiography used to measure true volume. From an accuracy standpoint, the admittance technique is superior to both the conductance technique calibrated with hypertonic saline injections, and calibrated with cuvettes. The device was then tested in six rats with a 24-hour chronic preparation. Stability of the animal preparation and careful calibration are important factors affecting the success of the device. PMID:21606560

  14. The Pressure-Volume-Temperature Equation of State of Iron-Rich (Mg,Fe)O

    NASA Astrophysics Data System (ADS)

    Wicks, J. K.; Jackson, J. M.; Zhuravlev, K. K.; Prakapenka, V.

    2012-12-01

    Seismic observations near the base of the core-mantle boundary (CMB) have detected 5-20 km thick patches in which the seismic wave velocities are reduced by up to 30%. These ultra-low velocity zones (ULVZs) have been interpreted as aggregates of partially molten material (e.g. Williams and Garnero 1996, Hernlund and Jellinek, 2010) or as solid, iron-enriched residues (e.g. Knittle and Jeanloz, 1991; Mao et al., 2006; Wicks et al., 2010), typically based on proposed sources of velocity reduction. The stabilities of these structure types have been explored through dynamic models that have assembled a relationship between ULVZ stability and density (Hernlund and Tackley, 2007; Bower et al., 2010). Now, to constrain the chemistry of ULVZs, more information is needed on the relationship between density and sound velocity of candidate phases. Recently, we have shown that the characteristically low sound speeds of ULVZs can be produced by small amounts of iron-rich (Mg,Fe)O, which is likely to be found in iron-rich assemblages based on current partitioning studies (eg. Sakai et al., 2010; Tange et al., 2009). We determined the Debye velocity (VD) of (Mg.1657Fe.84)O using nuclear resonant inelastic x-ray scattering (NRIXS), and calculated the seismically relevant compressional (VP) and shear (VS) wave velocities up to 120 GPa using an equation of state of a similar composition (Wicks et al., 2010). These densities and sound velocities, in turn, are consistent with reasonable morphologies of modeled solid ULVZs (Bower et al., 2011). To increase the accuracy of density and sound velocity predictions, measurements must be made at elevated temperatures to correctly predict the properties of iron-rich (Mg,Fe)O at mantle conditions. In this study, we present the pressure-volume-temperature equation of state of (Mg.0657Fe.94)O measured up to pressures of 120 GPa and temperatures of 2000 K. Volume was measured with x-ray diffraction at beamline 13-ID-D of the Advanced Photon

  15. The linear relationship between systolic pulmonary artery pressure and mean pulmonary artery pressure is maintained regardless of autonomic or rhythm disturbances.

    PubMed

    Vanden Eynden, Frédéric; Racapé, Judith; Vincent, Jame; Vachiéry, Jean-Luc; Bové, Thierry; Van Nooten, Guido

    2016-03-31

    In the pulmonary circulation, there is a linear relationship between systolic pulmonary arterial pressure (SPAP) and mean pulmonary arterial pressure (MPAP). The aim of this study was to determine the passive or active nature of this mechanism by exploring the relationship in patients with and without autonomic rhythm control of the heart and pulmonary circulation. Pulmonary arterial pressure recordings from non-transplanted patients and patients with heart transplants or double lung transplants were retrospectively reviewed. The relationships between systolic, diastolic, and mean pulmonary arterial pressures were explored. A linear relationship was observed between the SPAP and MPAP, whether patients were paced (MPAP = 0.56 SPAP + 3.86 mmHg, r (2)  = 0.889), treated with inotropes (MPAP = 0.55 SPAP + 5.52 mmHg, r (2)  = 0.947) or pulmonary vasodilators (MPAP = 0.58 SPAP + 2.41 mmHg, r (2)  = 0.927), were exercising (MPAP = 0.61 SPAP + 1.18 mmHg, r (2)  = 0.967), had a heart transplant (MPAP = 0.66 SPAP +0.87 mmHg, r (2)  = 0.849), a double lung transplant (MPAP = 0.7 SPAP +0.48 mmHg, r (2)  = 0.915), or no intervention (MPAP = 0.59 SPAP +1.75 mmHg, r (2)  = 0.937). We demonstrate that the linear relationship between SPAP and MPAP remains in several situations. Therefore, we conclude that the underlying mechanism is a passive consequence of the elastic properties of the cardiopulmonary unit.

  16. Relationship between FEV1 and arterial stiffness in elderly people with chronic obstructive pulmonary disease.

    PubMed

    Costanzo, Luisa; Pedone, Claudio; Battistoni, Fabrizio; Chiurco, Domenica; Santangelo, Simona; Antonelli-Incalzi, Raffaele

    2017-04-01

    Chronic obstructive pulmonary disease (COPD) is highly prevalent in the elderly, and both COPD and age per se are associated with cardiovascular morbidity. We tested the hypothesis that in elderly COPD patients airflow limitation is associated with arterial stiffness and the relationship, if any, is related to endothelial function and systemic inflammation. We evaluated lung function, augmentation index (AIx), flow-mediated dilation (FMD), Interleukin-6 (IL-6), and asymmetric dymethilarginine (ADMA) levels in 76 subjects (mean age 73.9 years, SD 6.2) attending a geriatric outpatient clinic. Participants with COPD (N = 41) and controls (N = 35) did not differ in terms of AIx (30 vs 28.2 %, P = 0.30) and FMD (14.2 vs 12.3 %, P = 0.10). Similarly, the two groups did not differ with respect to mean concentrations of inflammation markers (IL-6 and C-reactive protein) and ADMA. Among COPD participants there was an inverse correlation between AIx and Forced Expiratory Volume in the first second (r = -0.349, P = 0.02). This relationship remained significant after correction for potential confounders, including markers of inflammation and ADMA levels (β = -0.194, P = 0.001). According to the results of this study, among COPD patients, bronchial patency and AIx are inversely related, and the relationship is explained neither by endothelial function nor by systemic inflammation. In elderly COPD people, increased arterial stiffness is related to reduced pulmonary function and it seems worth testing as a potential marker of higher cardiovascular risk.

  17. Influence of body weight and body conformation on the pressure-volume curve during capnoperitoneum in dogs.

    PubMed

    Dorn, Melissa J; Bockstahler, Barbara A; Dupré, Gilles P

    2017-05-01

    OBJECTIVE To evaluate the pressure-volume relationship during capnoperitoneum in dogs and effects of body weight and body conformation. ANIMALS 86 dogs scheduled for routine laparoscopy. PROCEDURES Dogs were allocated into 3 groups on the basis of body weight. Body measurements, body condition score, and body conformation indices were calculated. Carbon dioxide was insufflated into the abdomen with a syringe, and pressure was measured at the laparoscopic cannula. Volume and pressure data were processed, and the yield point, defined by use of a cutoff volume (COV) and cutoff pressure (COP), was calculated. RESULTS 20 dogs were excluded because of recording errors, air leakage attributable to surgical flaws, or trocar defects. For the remaining 66 dogs, the pressure-volume curve was linear-like until the yield point was reached, and then it became visibly exponential. Mean ± SD COP was 5.99 ± 0.805 mm Hg. No correlation was detected between yield point, body variables, or body weight. Mean COV was 1,196.2 ± 697.9 mL (65.15 ± 20.83 mL of CO2/kg), and COV was correlated significantly with body weight and one of the body condition indices but not with other variables. CONCLUSION AND CLINICAL RELEVANCE In this study, there was a similar COP for all dogs of all sizes. In addition, results suggested that increasing the abdominal pressure after the yield point was reached did not contribute to a substantial increase in working space in the abdomen. No correlation was found between yield point, body variables, and body weight.

  18. Relationship between total and differential leukocyte counts and isolated coronary artery ectasia.

    PubMed

    Kocaman, Sinan Altan; Taçoy, Gülten; Sahinarslan, Asife; Cengel, Atiye

    2008-08-01

    Coronary artery ectasia (CAE) is a clinical entity characterized by localized or diffuse dilatation of more than or equal to 1.5 times that of the normal adjacent segments of vessels. Although the etiopathogenesis is not clearly understood, some studies have shown that CAE may be a form of atherosclerosis and has more potent inflammatory properties. Leukocytes have a crucial role in the development of inflammatory processes. We aimed to investigate a possible relationship between leukocytes and the coronary ectatic process without coronary artery disease (CAD) and to compare it with the inflammatory atherosclerotic process related to leukocytes. The study population consisted of 371 patients. We divided the patients into three groups: 42 patients with isolated CAE as group I, 279 patients with CAD as group II, and 50 control participants with normal coronary arteries (NCA) as group III. The counts of total leukocytes (7348+/-1898, 7569+/-1619, and 6770+/-1748 cells/mm, P=0.002), neutrophils (4260+/-2169, 4529+/-1380, and 4040+/-1649 cells/mm, P=0.037) and monocytes (630+/-216, 583+/-198, and 480+/-140 cells/mm, P<0.001) were significantly different among the CAE, CAD, and NCA groups, respectively. The CAE group also had significantly higher leukocyte and subtype counts than the nonobstructive CAD subgroup and NCA group. This study demonstrates that total and differential leukocyte counts, which play an important role in inflammation, are increased in patients with isolated CAE. In conclusion, this study's findings show that leukocytes may play an important role in the development of CAE independently of the atherosclerotic process.

  19. Relationship between serum sodium level and coronary artery abnormality in Kawasaki disease

    PubMed Central

    Park, Sora; Kim, Ji Hong

    2017-01-01

    Purpose Kawasaki disease (KD) is an immune-related multisystemic vasculitis that occurs in children, especially ensuing from a coronary artery abnormality. Sodium level is known to be related to vascular injury, which could affect the progress of KD. The purpose of this study was to determine the serum sodium levels that could predict the occurrence of cardiac and coronary artery events in KD. Methods We conducted a retrospective review of medical records for 104 patients with KD from January 2015 to December 2015. Patients with serum Na levels of <135 mEq/L at the time of initial diagnosis were assigned to the hyponatremia group. Laboratory findings and echocardiographic data were analyzed for various aspects. Results Among the 104 patients with KD, 91 were included in the study, of whom 48 (52.7%) had hyponatremia. The degree of fever, white blood cell count, percentage of neutrophils, percentage of lymphocytes, total bilirubin level, brain natriuretic peptide level, erythrocyte sedimentation rate, and C-reactive protein level were higher in the patients with hyponatremia. They also demonstrated a trend of larger coronary artery diameters based on Z scores. Conclusion The severity of vascular inflammation in acute KD with hyponatremia might worsen the prognosis of coronary vasculature. Although no statistically significant correlation was found between the initial serum sodium levels and coronary arteriopathy in the patients with KD in this study, a long-term follow-up study with a larger number of enrolled patients should be designed in the future to elucidate the relationship between serum sodium level and coronary arteriopathy in patients with KD. PMID:28289432

  20. The Relationship Between Oxygen Reserve Index and Arterial Partial Pressure of Oxygen During Surgery

    PubMed Central

    Dorotta, Ihab L.; Wells, Briana; Juma, David; Applegate, Patricia M.

    2016-01-01

    BACKGROUND: The use of intraoperative pulse oximetry (Spo2) enhances hypoxia detection and is associated with fewer perioperative hypoxic events. However, Spo2 may be reported as 98% when arterial partial pressure of oxygen (Pao2) is as low as 70 mm Hg. Therefore, Spo2 may not provide advance warning of falling arterial oxygenation until Pao2 approaches this level. Multiwave pulse co-oximetry can provide a calculated oxygen reserve index (ORI) that may add to information from pulse oximetry when Spo2 is >98%. This study evaluates the ORI to Pao2 relationship during surgery. METHODS: We studied patients undergoing scheduled surgery in which arterial catheterization and intraoperative arterial blood gas analysis were planned. Data from multiple pulse co-oximetry sensors on each patient were continuously collected and stored on a research computer. Regression analysis was used to compare ORI with Pao2 obtained from each arterial blood gas measurement and changes in ORI with changes in Pao2 from sequential measurements. Linear mixed-effects regression models for repeated measures were then used to account for within-subject correlation across the repeatedly measured Pao2 and ORI and for the unequal time intervals of Pao2 determination over elapsed surgical time. Regression plots were inspected for ORI values corresponding to Pao2 of 100 and 150 mm Hg. ORI and Pao2 were compared using mixed-effects models with a subject-specific random intercept. RESULTS: ORI values and Pao2 measurements were obtained from intraoperative data collected from 106 patients. Regression analysis showed that the ORI to Pao2 relationship was stronger for Pao2 to 240 mm Hg (r2 = 0.536) than for Pao2 over 240 mm Hg (r2 = 0.0016). Measured Pao2 was ≥100 mm Hg for all ORI over 0.24. Measured Pao2 was ≥150 mm Hg in 96.6% of samples when ORI was over 0.55. A random intercept variance component linear mixed-effects model for repeated measures indicated that Pao2 was significantly related to ORI

  1. The Relationship Between Oxygen Reserve Index and Arterial Partial Pressure of Oxygen During Surgery.

    PubMed

    Applegate, Richard L; Dorotta, Ihab L; Wells, Briana; Juma, David; Applegate, Patricia M

    2016-09-01

    The use of intraoperative pulse oximetry (SpO2) enhances hypoxia detection and is associated with fewer perioperative hypoxic events. However, SpO2 may be reported as 98% when arterial partial pressure of oxygen (PaO2) is as low as 70 mm Hg. Therefore, SpO2 may not provide advance warning of falling arterial oxygenation until PaO2 approaches this level. Multiwave pulse co-oximetry can provide a calculated oxygen reserve index (ORI) that may add to information from pulse oximetry when SpO2 is >98%. This study evaluates the ORI to PaO2 relationship during surgery. We studied patients undergoing scheduled surgery in which arterial catheterization and intraoperative arterial blood gas analysis were planned. Data from multiple pulse co-oximetry sensors on each patient were continuously collected and stored on a research computer. Regression analysis was used to compare ORI with PaO2 obtained from each arterial blood gas measurement and changes in ORI with changes in PaO2 from sequential measurements. Linear mixed-effects regression models for repeated measures were then used to account for within-subject correlation across the repeatedly measured PaO2 and ORI and for the unequal time intervals of PaO2 determination over elapsed surgical time. Regression plots were inspected for ORI values corresponding to PaO2 of 100 and 150 mm Hg. ORI and PaO2 were compared using mixed-effects models with a subject-specific random intercept. ORI values and PaO2 measurements were obtained from intraoperative data collected from 106 patients. Regression analysis showed that the ORI to PaO2 relationship was stronger for PaO2 to 240 mm Hg (r = 0.536) than for PaO2 over 240 mm Hg (r = 0.0016). Measured PaO2 was ≥100 mm Hg for all ORI over 0.24. Measured PaO2 was ≥150 mm Hg in 96.6% of samples when ORI was over 0.55. A random intercept variance component linear mixed-effects model for repeated measures indicated that PaO2 was significantly related to ORI (β[95% confidence interval] = 0

  2. The relationship between coenzyme Q10, oxidative stress, and antioxidant enzymes activities and coronary artery disease.

    PubMed

    Lee, Bor-Jen; Lin, Yi-Chin; Huang, Yi-Chia; Ko, Ya-Wen; Hsia, Simon; Lin, Ping-Ting

    2012-01-01

    A higher oxidative stress may contribute to the pathogenesis of coronary artery disease (CAD). The purpose of this study was to investigate the relationship between coenzyme Q10 concentration and lipid peroxidation, antioxidant enzymes activities and the risk of CAD. Patients who were identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery were assigned to the case group (n = 51). The control group (n = 102) comprised healthy individuals with normal blood biochemical values. The plasma coenzyme Q10, malondialdehyde (MDA) and antioxidant enzymes activities (catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx)) were measured. Subjects with CAD had significant lower plasma coenzyme Q10, CAT and GPx activities and higher MDA and SOD levels compared to those of the control group. The plasma coenzyme Q10 was positively correlated with CAT and GPx activities and negatively correlated with MDA and SOD. However, the correlations were not significant after adjusting for the potential confounders of CAD with the exception of SOD. A higher level of plasma coenzyme Q10 (≥ 0.52 μmol/L) was significantly associated with reducing the risk of CAD. Our results support the potential cardioprotective impact of coenzyme Q10.

  3. [The relationship between conventional ECG and the culprit coronary artery in acute myocardial infarct].

    PubMed

    César, L A; Moretti, M A; Ramires, J A; Nussbacher, A; Consolim, F M; Moffa, P J; da Luz, P L; Bellotti, G M; Pileggi, F

    1994-08-01

    To evaluate electrocardiogram (ECG) in detecting acute myocardial infarction (AMI) during the first 12 hours of symptoms and its relationship to the culprit coronary artery. We studied 68 patients aged 55.6 (30 to 76) years, 61 males, with AMI confirmed by elevated CKMB isoenzyme and cinecoronariography (CINE). In all of them we obtained two ECG: first (i), with < 12 hours of symptoms and a second, > or = 5 days during evolution. ECG were analyzed in order to disclose up and downward ST-T segments > or = 1 mm, new Q waves > or = 0.04 s and R/S > or = 1 plus downward ST-T segment in leads V1 and V2. Then we have done correlation between these and the culprit coronary lesions at CINE. The culprit coronary lesions were: right coronary artery (RCA) in 16, left circumflex (LC) in 26 and left anterior descending (LAD) in 31 cases. According to the ECG, the RCA determined inferior AMI in all patients and the LC only in 62% of cases. Posterior AMI due to LC was seen in 81% of cases at ECG and, associated with lateral AMI, in 52%. Lone lateral AMI was seen in 5% and true posterior in 14% of cases, all of them due to LC. False negative ECG (i) in AMI is in fact due to LC occlusion which, frequently, causes posterior wall more then inferior wall myocardial infarction at ECG.

  4. A Cross-sectional Study of the Relationship Between Habitual Tea Consumption and Arterial Stiffness.

    PubMed

    Lin, Qing-Fei; Qiu, Chang-Sheng; Wang, Sai-Lan; Huang, Li-Fang; Chen, Zhi-Yuan; Chen, Yun; Chen, Gang

    2016-01-01

    To explore the relationship between habitual tea consumption and arterial stiffness. This is a cross-sectional, epidemiological survey of 6589 male and female residents aged 40-75 in Wuyishan, Fujian Province, China. Tea consumption and other lifestyle characteristics were obtained by structured questionnaires. Pulse wave velocity (PWV) and ankle-brachial pressure index (ABI) were measured using an automated analyzer. Among the 5006 analyzed subjects, 1564 adults (31.2%) consumed tea once or more per week for at least one year. The levels of brachial-ankle pulse wave velocity (ba-PWV) were lowest among subjects who consumed tea habitually for more than 10 years compared with the other 3 subgroups (nonhabitual, 1 to 5 years, and 6 to 10 years habitual tea drinkers), and the levels of ba-PWV were lower with subjects who consumed 10-20 and >20 g/d tea habitually compared to nonhabitual tea drinkers. As the duration and the daily amount of habitual tea consumption increased the average ba-PWV decreased. Multiple logistic regression models revealed that habitual tea consumption was a positive predictor for ba-PWV (odds ratio [OR] = 0.63, 95% confidence interval [CI], 0.57-0.70). Habitual tea consumption may have a protective effect against arterial stiffness, especially for subjects who have habitually consumed tea for more than 6 years and >10 g daily.

  5. Relationship of 133Xe cerebral blood flow to middle cerebral arterial flow velocity in men at rest

    NASA Technical Reports Server (NTRS)

    Clark, J. M.; Skolnick, B. E.; Gelfand, R.; Farber, R. E.; Stierheim, M.; Stevens, W. C.; Beck, G. Jr; Lambertsen, C. J.

    1996-01-01

    Cerebral blood flow (CBF) was measured by 133Xe clearance simultaneously with the velocity of blood flow through the left middle cerebral artery (MCA) over a wide range of arterial PCO2 in eight normal men. Average arterial PCO2, which was varied by giving 4% and 6% CO2 in O2 and by controlled hyperventilation on O2, ranged from 25.3 to 49.9 mm Hg. Corresponding average values of global CBF15 were 27.2 and 65.0 ml 100 g min-1, respectively, whereas MCA blood-flow velocity ranged from 42.8 to 94.2 cm/s. The relationship of CBF to MCA blood-flow velocity over the imposed range of arterial PCO2 was described analytically by a parabola with the equation: CBF = 22.8 - 0.17 x velocity + 0.006 x velocity2 The observed data indicate that MCA blood-flow velocity is a useful index of CBF response to change in arterial PCO2 during O2 breathing at rest. With respect to baseline values measured while breathing 100% O2 spontaneously, percent changes in velocity were significantly smaller than corresponding percent changes in CBF at increased levels of arterial PCO2 and larger than CBF changes at the lower arterial PCO2. These observed relative changes are consistent with MCA vasodilation at the site of measurement during exposure to progressive hypercapnia and also during extreme hyperventilation hypocapnia.

  6. Relationship of 133Xe cerebral blood flow to middle cerebral arterial flow velocity in men at rest

    NASA Technical Reports Server (NTRS)

    Clark, J. M.; Skolnick, B. E.; Gelfand, R.; Farber, R. E.; Stierheim, M.; Stevens, W. C.; Beck, G. Jr; Lambertsen, C. J.

    1996-01-01

    Cerebral blood flow (CBF) was measured by 133Xe clearance simultaneously with the velocity of blood flow through the left middle cerebral artery (MCA) over a wide range of arterial PCO2 in eight normal men. Average arterial PCO2, which was varied by giving 4% and 6% CO2 in O2 and by controlled hyperventilation on O2, ranged from 25.3 to 49.9 mm Hg. Corresponding average values of global CBF15 were 27.2 and 65.0 ml 100 g min-1, respectively, whereas MCA blood-flow velocity ranged from 42.8 to 94.2 cm/s. The relationship of CBF to MCA blood-flow velocity over the imposed range of arterial PCO2 was described analytically by a parabola with the equation: CBF = 22.8 - 0.17 x velocity + 0.006 x velocity2 The observed data indicate that MCA blood-flow velocity is a useful index of CBF response to change in arterial PCO2 during O2 breathing at rest. With respect to baseline values measured while breathing 100% O2 spontaneously, percent changes in velocity were significantly smaller than corresponding percent changes in CBF at increased levels of arterial PCO2 and larger than CBF changes at the lower arterial PCO2. These observed relative changes are consistent with MCA vasodilation at the site of measurement during exposure to progressive hypercapnia and also during extreme hyperventilation hypocapnia.

  7. Is there a surgeon or hospital volume-outcome relationship in off-pump coronary artery bypass surgery?

    PubMed

    Sepehripour, Amir H; Athanasiou, Thanos

    2013-02-01

    A best evidence topic was written according to a structured protocol. The question addressed was whether there is a surgeon or hospital volume-outcome relationship in patients undergoing off-pump coronary artery bypass surgery. A total of 281 papers were found using the reported searches, of which six represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. The studies found analysed the outcomes of off-pump coronary artery bypass surgery in relation to surgeon or hospital volume and evaluated the presence of a volume-outcome relationship. Reported measures included mortality and major adverse cardiovascular and cerebrovascular events. The methodological quality and strength of each study for exploring volume-outcome relationships were quantitatively assessed using a predefined scoring system. Three studies analysed surgeon volume and three studies analysed hospital volume. The two largest and most recent studies presented a significant volume-outcome relationship in mortality and postoperative complications. Perhaps owing to the smaller sample size, this significant relationship in mortality was not observed in the four smaller studies; however, one of these studies demonstrated a significantly positive relationship for postoperative complications and another study demonstrated a similar significant relationship for the number of grafts and the degree of completeness of revascularization. While the volume-outcome relationship in coronary artery bypass graft surgery is very well-documented, the technically challenging nature of off-pump surgery, the length of the learning curve associated with the operation and the higher risk profile of patients undergoing off-pump surgery in comparison with routine on-pump surgery render these results difficult to interpret. Although our review does support the idea of a volume-outcome relationship in off-pump coronary

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

    NASA Astrophysics Data System (ADS)

    Cymberknop, L.; Legnani, W.; Pessana, F.; Bia, D.; Zócalo, Y.; Armentano, R. L.

    2011-12-01

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

  9. Reappraising the surface anatomy of the pterion and its relationship to the middle meningeal artery.

    PubMed

    Ma, Siyan; Baillie, Louisa J M; Stringer, Mark D

    2012-04-01

    Despite its clinical importance, the surface anatomy of the pterion is inconsistently reported. This study reappraises the surface marking of the pterion and its relationship to the middle meningeal artery (MMA). The position and morphology of the pterion were analyzed in the Frankfurt plane in 76 adult skulls and 50 adult cranial cone beam CT scans. Relationship to the anterior branch of the MMA was examined in the skulls. Measurement reproducibility was assessed in a 20% randomly selected sample. In the skulls, the majority of pteria were sphenoparietal (78%), followed by epipteric (16%) and frontotemporal (5%). The center of the pterion was a mean of 26 ± 4 mm behind and 11 ± 4 mm above the posterolateral margin of the frontozygomatic suture; measurements were reproducible and consistent between sides and genders. Distances from the frontozygomatic suture were slightly greater (29 and 16 mm, respectively) in cranial CTs. A one centimeter circle centered on the midpoint of the pterion overlapped the anterior branch of the MMA in 68% of skulls; the artery was a few millimeters posterior in the remainder. Mean skull thickness at the midpoint of the pterion was 4.4 mm compared to 1 mm at its thinnest point in the squamous temporal bone. In conclusion, in most adults, the pterion lies within a one centimeter diameter circle 2.6 cm behind and 1.3 cm above the posterolateral margin of the frontozygomatic suture (which is easily palpable in vivo). This region overlaps the anterior branch of the MMA in two-thirds of cases.

  10. Use of pressure-volume conductance catheters in real-time cardiovascular experimentation.

    PubMed

    Wei, Abraham E; Maslov, Mikhail Y; Pezone, Matthew J; Edelman, Elazer R; Lovich, Mark A

    2014-11-01

    Most applications of pressure-volume conductance catheter measurements assess cardiovascular function at a single point in time after genetic, pharmacologic, infectious, nutritional, or toxicologic manipulation. Use of these catheters as a continuous monitor, however, is fraught with complexities and limitations. Examples of the limitations and optimal use of conductance catheters as a continuous, real-time monitor of cardiovascular function are demonstrated during inotropic drug infusion in anesthetised rats. Inotropic drug infusion may alter ventricular dimensions causing relative movement of a well-positioned catheter, generating artifacts, including an abrupt pressure rise at end-systole that leads to over estimation of indices of contractility (max dP/dt) and loss of stroke volume signal. Simple rotation of the catheter, echocardiography-guided placement to the centre of the ventricle, or ventricular expansion through crystalloid infusion may correct for these artifacts. Fluid administration, however, alters left ventricular end-diastolic pressure and volume and therefore stroke volume, thereby obscuring continuous real-time haemodynamic measurements. Pressure-volume artifacts during inotropic infusion are caused by physical contact of the catheter with endocardium. Repeated correction of catheter position may be required to use pressure volume catheters as a continuous real-time monitor during manipulations that alter ventricular dimensions, such as inotropic therapy. Copyright © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  11. Examination of the Relationship between Oral Health and Arterial Sclerosis without Genetic Confounding through the Study of Older Japanese Twins

    PubMed Central

    Kurushima, Yuko; Ikebe, Kazunori; Matsuda, Ken-ichi; Enoki, Kaori; Ogata, Soshiro; Yamashita, Motozo; Murakami, Shinya; Maeda, Yoshinobu

    2015-01-01

    Objective Although researchers have recently demonstrated a relationship between oral health and arterial sclerosis, the genetic contribution to this relationship has been ignored even though genetic factors are expected to have some effect on various diseases. The aim of this study was to evaluate oral health as a significant risk factor related to arterial sclerosis after eliminating genetic confounding through study of older Japanese twins. Subjects and Methods Medical and dental surveys were conducted individually for 106 Japanese twin pairs over the age of 50 years. Maximal carotid intima-media thickness (IMT-Cmax) was measured as a surrogate marker of arterial sclerosis. IMT-Cmax > 1.0 mm was diagnosed as arterial sclerosis. All of the twins were examined for the number of remaining teeth, masticatory performance, and periodontal status. We evaluated each measurement related with IMT-Cmax and arterial sclerosis using generalized estimating equations analysis adjusted for potential risk factors. For non-smoking monozygotic twins, a regression analysis using a “between within” model was conducted to evaluate the relationship between IMT-Cmax and the number of teeth as the environmental factor controlling genetic and familial confounding. Results We examined 91 monozygotic and 15 dizygotic twin pairs (males: 42, females: 64) with a mean (± standard deviation) age of 67.4 ± 10.0 years. Out of all of the oral health-related measurements collected, only the number of teeth was significantly related to arterial sclerosis (odds ratio: 0.72, 95% confidence interval: 0.52-0.99 per five teeth). Regression analysis showed a significant association between the IMT-Cmax and the number of teeth as an environmental factor (p = 0.037). Conclusions Analysis of monozygotic twins older than 50 years of age showed that having fewer teeth could be a significant environmental factor related to arterial sclerosis, even after controlling for genetic and familial confounding

  12. Examination of the Relationship between Oral Health and Arterial Sclerosis without Genetic Confounding through the Study of Older Japanese Twins.

    PubMed

    Kurushima, Yuko; Ikebe, Kazunori; Matsuda, Ken-Ichi; Enoki, Kaori; Ogata, Soshiro; Yamashita, Motozo; Murakami, Shinya; Maeda, Yoshinobu

    2015-01-01

    Although researchers have recently demonstrated a relationship between oral health and arterial sclerosis, the genetic contribution to this relationship has been ignored even though genetic factors are expected to have some effect on various diseases. The aim of this study was to evaluate oral health as a significant risk factor related to arterial sclerosis after eliminating genetic confounding through study of older Japanese twins. Medical and dental surveys were conducted individually for 106 Japanese twin pairs over the age of 50 years. Maximal carotid intima-media thickness (IMT-Cmax) was measured as a surrogate marker of arterial sclerosis. IMT-Cmax > 1.0 mm was diagnosed as arterial sclerosis. All of the twins were examined for the number of remaining teeth, masticatory performance, and periodontal status. We evaluated each measurement related with IMT-Cmax and arterial sclerosis using generalized estimating equations analysis adjusted for potential risk factors. For non-smoking monozygotic twins, a regression analysis using a "between within" model was conducted to evaluate the relationship between IMT-Cmax and the number of teeth as the environmental factor controlling genetic and familial confounding. We examined 91 monozygotic and 15 dizygotic twin pairs (males: 42, females: 64) with a mean (± standard deviation) age of 67.4 ± 10.0 years. Out of all of the oral health-related measurements collected, only the number of teeth was significantly related to arterial sclerosis (odds ratio: 0.72, 95% confidence interval: 0.52-0.99 per five teeth). Regression analysis showed a significant association between the IMT-Cmax and the number of teeth as an environmental factor (p = 0.037). Analysis of monozygotic twins older than 50 years of age showed that having fewer teeth could be a significant environmental factor related to arterial sclerosis, even after controlling for genetic and familial confounding.

  13. The durability of silicone versus latex mock arteries.

    PubMed

    Conti, J C; Strope, E R; Goldenberg, L M; Price, K S

    2001-01-01

    Latex mock arteries used in medical device testing allow researchers to evaluate mechanical characteristics of intravascular medical products without using animal or human clinical studies for this data. Such intravascular situations include determining properties such as drag and steerability of catheters, recoil of vascular stents, and clinician training. In fatigue testing, the latex mock arteries are used to receive deployed products and are then repeatedly pressurized at biologically relevant pressures to determine the long term durability of the product. By matching dimensions and pressure-volume relationships (compliance) of these latex tubes, researchers have a reliable means to evaluate and predict product lifetimes. The problem with latex mock arteries is two-fold: First, they are opaque so the product inside the artery cannot be seen during evaluation of the integrity of the product or during clinical training sessions. Second, latex tubes fatigue; therefore, the loading that they place on the internalized products varies with time. During long term durability studies, latex tubes may have to be replaced as often as every 100 million cycles. This can be problematic with products that are difficult to redeploy. We have developed a clear silicone mock artery system that allows us to fabricate three-dimensional objects, including tubes with precise geometric and mechanical properties. Our evaluations show that the mock arteries can be stressed up to 400 million cycles with little or no change in mechanical properties. We are in the process of continuing evaluations to determine long term durability.

  14. Relationship of dental diseases with coronary artery diseases and diabetes in Bangladesh

    PubMed Central

    Choudhury, Arup Ratan; Choudhury, Kamrun Nahar

    2016-01-01

    Background Evidence suggests that dental diseases might have a role in the development and progression of coronary artery diseases (CAD) and diabetes mellitus (DM). The objective of this study was to determine the relationship of dental diseases with CAD and DM in Bangladesh. Methods We conducted a cross-sectional study among 216 consecutive patients admitted in a tertiary hospital between March and July 2011. Data were collected on socio-demographic status, smoking, blood pressure (BP), diet, physical activities, and biochemical measurements of lipid profile, glycated hemoglobin (HbA1c), C-reactive protein (CRP), fibrinogen, creatinine kinase MB (CK-MB), troponin, serum creatinine and serum glutamic-pyruvic transaminase (SGPT). CAD was detected using echocardiographic and coronary angiogram (CAG) reports. All patients underwent oral examination for dental disease. Relationship between dental disease with CAD and DM were explored statistically. Results The mean age of the participants was 57.8±12.5 years and almost two-thirds (67.1%) were male. A great majority of the patients had CAD (90.3%) and type 2 DM (83.8%), and only 44% suffered from dental diseases. Less than one-third patients presented with acute myocardial infarction (MI), 23% with old MI, 11% unstable angina (UA) and 26.4% with non-ST elevation MI. Logistic regression results indicated that patients with DM and CAD had approximately 2.6 and 4.6 times more odds of association with dental diseases than those without DM and CAD (both P value <0.001). Conclusions This study suggests a relationship of dental diseases with CAD and DM among Bangladeshi patients. Further studies are required to confirm these relationships in large clinical studies. Screening for CAD and DM should be considered among those with dental diseases and vice-versa. PMID:27054102

  15. The Emergence of Quantification in the Pressure-Volume Relationship for Gases: A Textbook Analysis.

    ERIC Educational Resources Information Center

    de Berg, Kevin C.

    1989-01-01

    Examines the possibility that part of the problem in the teaching of physical science may lie in teaching-learning materials. Selects 14 chemistry textbooks and 14 physics textbooks in Australia. Analyzes them based on learning theory and scientific literacy. (YP)

  16. PRESSURE-VOLUME RELATIONSHIP OF THE FUNDULUS EGG IN SEA WATER AND IN SUCROSE

    PubMed Central

    Kao, C. Y.

    1956-01-01

    Upon activation, an internal hydrostatic pressure develops within the Fundulus egg, and compresses the egg proper to a reduced volume. When the perivitelline pressure is abolished by a highly hypertonic sucrose solution, the egg volume increases. As sucrose penetrates the chorion, the volume again decreases. The relation between P and V in these conditions is inverse, and approximates a rectangular hyperbola. The limiting factor causing most of the deviation is shown to be the incompressible fraction. It is concluded that the volume of the egg proper is controlled by the perivitelline pressure, and that the effect of hypertonic sucrose solution is exerted by lowering the pressure and thereby increasing membrane permeability non-specifically. It is also shown that some permanent alterations occur within the plasma membrane during activation that reduce the permeance, and thereby, increase the incompressible fraction. PMID:13357739

  17. Quantitative analysis of anatomical relationship between cavernous segment internal carotid artery and pituitary macroadenoma

    PubMed Central

    Lin, Bon-Jour; Chung, Tzu-Tsao; Lin, Meng-Chi; Lin, Chin; Hueng, Dueng-Yuan; Chen, Yuan-Hao; Hsia, Chung-Ching; Ju, Da-Tong; Ma, Hsin-I; Liu, Ming-Ying; Tang, Chi-Tun

    2016-01-01

    Abstract Cavernous segment internal carotid artery (CSICA) injury during endoscopic transsphenoidal surgery for pituitary tumor is rare but fatal. The aim of this study is to investigate anatomical relationship between pituitary macroadenoma and corresponding CSICA using quantitative means with a sense to improve safety of surgery. In this retrospective study, a total of 98 patients with nonfunctioning pituitary macroadenomas undergoing endoscopic transsphenoidal surgeries were enrolled from 2005 to 2014. Intercarotid distances between bilateral CSICAs were measured in the 4 coronal levels, namely optic strut, convexity of carotid prominence, median sella turcica, and dorsum sellae. Parasellar extension was graded and recorded by Knosp–Steiner classification. Our findings indicated a linear relationship between size of pituitary macroadenoma and intercarotid distance over CSICA. The correlation was absent in pituitary macroadenoma with Knosp–Steiner grade 4 parasellar extension. Bigger pituitary macroadenoma makes more lateral deviation of CSICA. While facing larger tumor, sufficient bony graft is indicated for increasing surgical field, working area and operative safety. PMID:27741111

  18. Quantitative analysis of anatomical relationship between cavernous segment internal carotid artery and pituitary macroadenoma.

    PubMed

    Lin, Bon-Jour; Chung, Tzu-Tsao; Lin, Meng-Chi; Lin, Chin; Hueng, Dueng-Yuan; Chen, Yuan-Hao; Hsia, Chung-Ching; Ju, Da-Tong; Ma, Hsin-I; Liu, Ming-Ying; Tang, Chi-Tun

    2016-10-01

    Cavernous segment internal carotid artery (CSICA) injury during endoscopic transsphenoidal surgery for pituitary tumor is rare but fatal. The aim of this study is to investigate anatomical relationship between pituitary macroadenoma and corresponding CSICA using quantitative means with a sense to improve safety of surgery.In this retrospective study, a total of 98 patients with nonfunctioning pituitary macroadenomas undergoing endoscopic transsphenoidal surgeries were enrolled from 2005 to 2014. Intercarotid distances between bilateral CSICAs were measured in the 4 coronal levels, namely optic strut, convexity of carotid prominence, median sella turcica, and dorsum sellae. Parasellar extension was graded and recorded by Knosp-Steiner classification.Our findings indicated a linear relationship between size of pituitary macroadenoma and intercarotid distance over CSICA. The correlation was absent in pituitary macroadenoma with Knosp-Steiner grade 4 parasellar extension.Bigger pituitary macroadenoma makes more lateral deviation of CSICA. While facing larger tumor, sufficient bony graft is indicated for increasing surgical field, working area and operative safety.

  19. The relationship between complete blood count parameters and Fontaine's Stages in patients with peripheral arterial disease.

    PubMed

    Demirtas, Sinan; Karahan, Oguz; Yazici, Suleyman; Guclu, Orkut; Caliskan, Ahmet; Yavuz, Celal; Kucuker, Aslihan; Mavitas, Binali

    2014-12-01

    The aim of the present study is to evaluate whether blood count parameters differ according to the stages of Fontaine's classification and to investigate the relationship between hemogram parameters and the severity of the disease. Eighty-two peripheral arterial disease patients were examined prospectively. Patients were classified according to the Fontaine classification system. Fifty newly diagnosed patients were included in the study. The neutrophil-to-lymphocyte ratio, mean platelet volume, and red blood cell distribution width values were recorded. Mean neutrophil-to-lymphocyte ratio values were found to be 3.31 ± 1.1% in Stage I, 3.11 ± 1.3% in Stage II, and 3.48 ± 1.1% in Stage III (p > 0.05). Mean platelet volume values were found to be 7.8 ± 0.6 fl (Stage I), 8.2 ± 1.0 fl (Stage II), and 9.0 ± 0.9 fl (Stage III) (p < 0.05). Red blood cell distribution width values were found to be 13.6 ± 1.0% in Stage I, 14.8 ± 1.7% in Stage II, and 15.4 ± 2.3% in Stage III, being significantly different among all three stages (p < 0.05). Both red blood cell distribution width and mean platelet volume are found to be associated with the severity of atherosclerotic disease in patients with peripheral arterial disease. This finding hypothesizes that complete blood counting parameters may serve as a beneficial and cost-effective method for monitoring atherosclerotic peripheral disease. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  20. Relationship of genetic variability and depressive symptoms to adverse events after coronary artery bypass graft surgery.

    PubMed

    Phillips-Bute, Barbara; Mathew, Joseph P; Blumenthal, James A; Morris, Richard W; Podgoreanu, Mihai V; Smith, Michael; Stafford-Smith, Mark; Grocott, Hilary P; Schwinn, Debra A; Newman, Mark F

    2008-11-01

    To assess genetic variability in two serotonin-related gene polymorphisms (MAOA-uVNTR and 5HTTLPR) and their relationships to depression and adverse cardiac events in a sample of patients undergoing coronary artery bypass surgery. A total of 427 coronary artery bypass graft (CABG) patients were genotyped for two polymorphisms and assessed for depressive symptoms at three time points, in accordance with the Center for Epidemiological Studies-Depression (CES-D): preoperative baseline; 6 months postoperative; and 1 year postoperative. Logistic regression was used to assess the association between depressive symptoms (CES-D = >16), genotype differences, and cardiac events. Because MAOA-uVNTR is sex-linked, males and females were analyzed separately for this polymorphism; sexes were combined for the 5HTTLPR analysis. Depressed patients were more likely than nondepressed patients to have a new cardiac event within 2 years of surgery (p < .0001); depressed patients who carry the long (L) allele of the 5HTTLPR polymorphism were more likely than the short/short (S/S carriers to have an event (p = .0002). Genetic associations with 6-month and 1-year postoperative depressive symptoms do not survive adjustment for baseline depressive symptoms. A serotonin-related gene polymorphism--5HTTLPR--was associated with adverse cardiac events post CABG, in combination with depressive symptoms. Because depressed patients with the L allele of the 5HTTLPR polymorphism were more likely to have an event compared with the S/S carriers, combining genetic and psychiatric profiling may prove useful in identifying patients at the highest risk for adverse outcomes post CABG.

  1. Brachial artery retrograde flow increases with age: relationship to physical function

    PubMed Central

    Credeur, Daniel P.; Dobrosielski, Devon A.; Arce-Esquivel, Arturo A.; Welsch, Michael A.

    2010-01-01

    The purpose of this study was to examine the flow velocity pattern of the brachial artery and to determine its relationship to measures of physical function. Subjects from the Louisiana Healthy Aging Study (n = 95; age = 84 ± 10 years) were evaluated. Brachial artery flow velocities and dimensions were measured using high-resolution ultrasonography. The continuous scale of physical function and performance test (CS-PFP10) was used to assess physical function. This test is based on the performance of 11 activities of daily living. Total CS-PFP10 score was 39.51 ± 21.21 U. Mean antegrade and retrograde velocities at rest were 14.2 ± 4.7 and 3.6 ± 2.2 cm/s, respectively. Ante-/retrograde ratio was 5.5 ± 4.6. Brachial artery diameter was 4.3 ± 0.7 mm. Pulse pressure and vascular conductance were 66 ± 18 mmHg, and 0.9 ± 0.5 ml/min/mmHg, respectively. Vascular conductance (r = −0.34), ante-/retrograde ratio (r = −0.42) and CS-PFP10 (r = −0.65) were inversely and retrograde velocity (r = 0.40) and pulse pressure (r = 0.36), were directly associated with age. Retrograde velocity was inversely related to vascular conductance (r = −0.27) and CS-PFP10 total score (r = −0.45). A MANOVA revealed that those with the higher CS-PFP10 scores had a lower retrograde velocity (P = 0.0001), but this association was, in part, age-dependent. Among nonagenarians (n = 52), those in the lower tertiles of the CS-PFP10 scores had significantly higher retrograde velocities compared to those in the higher tertiles (P = 0.035). These data indicate an increase in brachial retrograde velocity with age. These hemodynamic changes are related to a decline in physical function. PMID:19565260

  2. Effects of hypercapnia and arterial hypotension and hypertension on cerebrospinal fluid pulse pressure and intracranial volume-pressure relationships.

    PubMed Central

    Avezaat, C J; van Eijndhoven, J H; Wyper, D J

    1980-01-01

    In twelve anaesthetised, ventilated dogs the effects of hypercapnia and pharmacologically induced arterial hypotension and hypertension on the interrelation between volume-pressure response (VPR) and cerebro-spinal fluid (CSF) pulse pressure were studied during continuous inflation of a supratentorial extradural balloon. Hypercapnia did not significantly affect the intracranial volume-pressure relationships, but did cause a significant increase in gradient of the relationship between CSF pulse pressure and intracranial pressure (ICP). Alteration of the arterial blood pressure showed opposite effects on VPR and CSF pulse pressure. A decrease in VPR and an increase in pulse pressure were observed during arterial hypotension; the reverse was found during arterial hypertension. The discrepancy between the effects on VPR and CSF pulse pressure of the variables under study was explained by changes in the transient increase in cerebral blood volume per cardiac cycle. On the basis of the results of this study it will be possible, during clinical ICP monitoring, to interpret changes in the CSF pulse pressure to ICP ratio in terms of changes in intracranial volume-pressure relationships. PMID:7373319

  3. Dorsal Scapular Artery Variations and Relationship to the Brachial Plexus, and a Related Thoracic Outlet Syndrome Case

    PubMed Central

    Verenna, Anne-Marie A.; Alexandru, Daniela; Karimi, Afshin; Brown, Justin M.; Bove, Geoffrey M.; Daly, Frank J.; Pastore, Anthony M.; Pearson, Helen E.; Barbe, Mary F.

    2016-01-01

    Rationale Knowledge of the relationship of the dorsal scapular artery (DSA) with the brachial plexus is limited. Objective We report a case of a variant DSA path, and revisit DSA origins and under-investigated relationship with the plexus in cadavers. Methods The DSA was examined in a male patient and 106 cadavers. Results In the case, we observed an unusual DSA compressing the lower plexus trunk, that resulted in intermittent radiating pain and paresthesia. In the cadavers, the DSA originated most commonly from the subclavian artery (71%), with 35% from the thyrocervical trunk. Nine sides of eight cadavers (seven females) had two DSA branches per side, with one branch from each origin. The most typical DSA path was a subclavian artery origin before passing between upper and middle brachial plexus trunks (40% of DSAs), versus between middle and lower trunks (23%), or inferior (4%) or superior to the plexus (1%). Following a thyrocervical trunk origin, the DSA passed most frequently superior to the plexus (23%), versus between middle and lower trunks (6%) or upper and middle trunks (4%). Bilateral symmetry in origin and path through the brachial plexus was observed in 13 of 35 females (37%) and 6 of 17 males (35%), with the most common bilateral finding of a subclavian artery origin and a path between upper and middle trunks (17%). Conclusion Variability in the relationship between DSA and trunks of the brachial plexus has surgical and clinical implications, such as diagnosis of thoracic outlet syndrome. PMID:28077957

  4. Vascular loops in the anterior inferior cerebellar artery, as identified by magnetic resonance imaging, and their relationship with otologic symptoms*

    PubMed Central

    de Abreu Junior, Luiz; Kuniyoshi, Cristina Hiromi; Wolosker, Angela Borri; Borri, Maria Lúcia; Antunes, Augusto; Ota, Vanessa Kiyomi Arashiro; Uchida, Daniela

    2016-01-01

    Objective To use magnetic resonance imaging to identify vascular loops in the anterior inferior cerebellar artery and to evaluate their relationship with otologic symptoms. Materials and Methods We selected 33 adults with otologic complaints who underwent magnetic resonance imaging at our institution between June and November 2013. Three experienced independent observers evaluated the trajectory of the anterior inferior cerebellar artery in relation to the internal auditory meatus and graded the anterior inferior cerebellar artery vascular loops according to the Chavda classification. Kappa and chi-square tests were used. Values of p < 0.05 were considered significant. Results The interobserver agreement was moderate. Comparing ears that presented vascular loops with those that did not, we found no association with tinnitus, hearing loss, or vertigo. Similarly, we found no association between the Chavda grade and any otological symptom. Conclusion Vascular loops do not appear to be associated with otoneurological manifestations. PMID:27818543

  5. Analytical relationship between arterial input impedance and the three-element Windkessel series resistance.

    PubMed

    Gnudi, G

    1998-07-01

    The recently proposed energy-balance method for estimating the series resistance of the three-element Windkessel model is reformulated in the frequency domain. New mathematical expressions are analytically derived, involving Fourier harmonics of pulsatile arterial pressure and flow. It is shown that the series resistance of the arterial three-element Windkessel model can be expressed as a weighted sum of the arterial input impedance moduli.

  6. Is there any relationship between coronary artery disease and postprandial triglyceride levels?

    PubMed

    Atar, Inci Aslı; Atar, Ilyas; Aydınalp, Alp; Ertan, Cağatay; Bozbaş, Hüseyin; Ozin, Bülent; Yıldırır, Aylin; Müderrisoğlu, Haldun

    2011-05-01

    We aimed to evaluate the relationship between postprandial triglyceride (PPTG) levels and coronary artery disease (CAD). A total of 80 patients were included in this prospective cohort study. Oral lipid loading was used in order to measure PPTG levels. In the fasting state and after the high fat breakfast, triglyceride levels were measured by enzymatic methods at 2nd, 4th, 6th and 8th hours. We made subgroup analysis to show the effects of lipid loading on triglyceride levels in patients with and without fasting hypertriglyceridemia. We evaluated triglyceride levels and changes of triglyceride levels in percentages after lipid loading using a general linear model for repeated measures. Sample size analysis was performed. Baseline clinical, demographic and laboratory characteristics of both groups were similar. The peak triglyceride levels were seen at the 4th hour in both groups. Triglyceride levels were significantly increased after lipid-rich-breakfast loading compared to baseline levels in both groups (p<0.001) but these changes were not significant (p=0.279). In patients with elevated fasting triglyceride levels, the area under the plasma triglyceride concentration curve was significantly larger in CAD group than control group (334±103 vs. 233±58 mg/dl, p=0.02). Our data show that in patients who have a high fasting triglyceride level, high levels of PPTG may be related to CAD, however high PPTG levels are not related to CAD in patients with normal fasting levels of triglyceride.

  7. Relationship between coronary artery ectasia, cocaine abuse and acute coronary syndromes

    PubMed Central

    Dendramis, Gregory; Paleologo, Claudia; Piraino, Davide; Assennato, Pasquale

    2016-01-01

    Coronary artery ectasia (CAE) often represents a coronary angiography finding casually detected or following the occurrence of an acute coronary syndrome. The pathogenetic role of cocaine abuse in the genesis of CAE is still little known and very few data are available in literature. We describe a case of a 31-year-old male cocaine user admitted to our department for typical acute chest pain. Coronary angiography showed diffuse coronary ectasia with slow flows and without hemodynamically significant stenosis. An increasing of matrix metalloproteinases values and a reduction of their tissue inhibitors was showed both during hospitalization and at one month after discharge. This case report emphasizes the close relationship between cocaine abuse, CAE and acute coronary syndromes in patients without hemodynamically significant coronary stenosis. As reported by Satran et al, cocaine abuse should be considered an important risk factor for CAE and these patients appear to be at increased risk of angina and acute myocardial infarct. Further studies that can strengthen this hypothesis would be useful to deepen and better analyze this interesting association. PMID:27231522

  8. Temporal Relationship Between Elevated Blood Pressure and Arterial Stiffening Among Middle-Aged Black and White Adults

    PubMed Central

    Chen, Wei; Li, Shengxu; Fernandez, Camilo; Sun, Dianjianyi; Lai, Chin-Chih; Zhang, Tao; Bazzano, Lydia; Urbina, Elaine M.; Deng, Hong-Wen

    2016-01-01

    This study assessed the temporal relationship between elevated blood pressure (BP) and arterial stiffness in a biracial (black-white) cohort of middle-aged adults aged 32–51 years from the semirural community of Bogalusa, Louisiana. Measurements of aortic-femoral pulse wave velocity (afPWV; n = 446) and large- and small-arterial compliance (n = 381) were obtained at 2 time points between 2000 and 2010, with an average follow-up period of 7 years. A cross-lagged path analysis model was used to examine the temporal relationship of elevated BP to arterial stiffness and elasticity. The cross-lagged path coefficients did not differ significantly between blacks and whites. The path coefficient (ρ2) from baseline BP to follow-up afPWV was significantly greater than the path coefficient (ρ1) from baseline afPWV to follow-up BP (ρ2 = 0.20 vs. ρ1 = 0.07 (P = 0.048) for systolic BP; ρ2 = 0.19 vs. ρ1 = 0.05 (P = 0.034) for diastolic BP). The results for this 1-directional path from baseline BP to follow-up afPWV were confirmed, although marginally significant, by using large- and small-artery elasticity measurements. These findings provide strong evidence that elevated BP precedes large-artery stiffening in middle-aged adults. Unlike the case in older adults, the large-arterial wall is not stiff enough in youth to alter BP levels during young adulthood. PMID:26960706

  9. THE RELATIONSHIP BETWEEN SEX HORMONES, SEX HORMONE BINDING GLOBULIN AND PERIPHERAL ARTERY DISEASE IN OLDER PERSONS

    PubMed Central

    Maggio, M; Cattabiani, C; Lauretani, F; Artoni, A; Bandinelli, S; Schiavi, G; Vignali, A; Volpi, R; Ceresini, G; Lippi, G; Aloe, R; De Vita, F; Giallauria, F; McDermott, MM; Ferrucci, L; Ceda, GP

    2014-01-01

    Objective The prevalence of peripheral artery disease (PAD) increases with aging and is higher in persons with metabolic syndrome and diabetes. PAD is associated with adverse outcomes, including frailty and disability. The protective effect of testosterone and sex hormone binding globulin (SHBG) for diabetes in men suggests that the biological activity of sex hormones may affect PAD, especially in older populations. Methods Nine hundred and twenty-one elderly subjects with data on SHBG, testosterone (T), estradiol (E2) were selected from InCHIANTI study. PAD was defined as an Ankle-Brachial Index (ABI) <0.90. Logistic regression models adjusted for age (Model 1), age, BMI, insulin, interleukin-6, physical activity, smoking, chronic diseases including metabolic syndrome (Model 2), and a final model including also sex hormones (Model 3) were performed to test the relationship between SHBG, sex hormones and PAD. Results The mean age (± SD) of the 419 men and 502 women was 75.0 ± 6.8 years (Sixty two participants (41 men, 21 women) had ABI<0.90. Men with PAD had SHBG levels lower than men without PAD (p=0.03). SHBG was negatively and independently associated with PAD in men (p=0.028). but not in women. The relationship was however attenuated after adjusting for sex hormones (p=0.07). The E2 was not significantly associated with PAD in both men and women. In women, but not in men, T was positively associated with PAD, even after adjusting for multiple confounders, including E2 (p=0.01). Conclusions Low SHBG and high T levels are significantly and independently associated with the presence of PAD in older men and women, respectively. PMID:23102785

  10. The relationship between sex hormones, sex hormone binding globulin and peripheral artery disease in older persons.

    PubMed

    Maggio, M; Cattabiani, C; Lauretani, F; Artoni, A; Bandinelli, S; Schiavi, G; Vignali, A; Volpi, R; Ceresini, G; Lippi, G; Aloe, R; De Vita, F; Giallauria, F; McDermott, M M; Ferrucci, L; Ceda, G P

    2012-12-01

    The prevalence of peripheral artery disease (PAD) increases with aging and is higher in persons with metabolic syndrome and diabetes. PAD is associated with adverse outcomes, including frailty and disability. The protective effect of testosterone and sex hormone binding globulin (SHBG) for diabetes in men suggests that the biological activity of sex hormones may affect PAD, especially in older populations. Nine hundred and twenty-one elderly subjects with data on SHBG, testosterone (T), estradiol (E2) were selected from InCHIANTI study. PAD was defined as an Ankle-Brachial Index (ABI) < 0.90. Logistic regression models adjusted for age (Model 1), age, BMI, insulin, interleukin-6, physical activity, smoking, chronic diseases including metabolic syndrome (Model 2), and a final model including also sex hormones (Model 3) were performed to test the relationship between SHBG, sex hormones and PAD. The mean age (±SD) of the 419 men and 502 women was 75.0 ± 6.8 years. Sixty two participants (41 men, 21 women) had ABI < 0.90. Men with PAD had SHBG levels lower than men without PAD (p = 0.03). SHBG was negatively and independently associated with PAD in men (p = 0.028) but not in women. The relationship was however attenuated after adjusting for sex hormones (p = 0.07). The E2 was not significantly associated with PAD in both men and women. In women, but not in men, T was positively associated with PAD, even after adjusting for multiple confounders, including E2 (p = 0.01). Low SHBG and high T levels are significantly and independently associated with the presence of PAD in older men and women, respectively. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. Morphometric analysis of diameter and relationship of vertebral artery with respect to transverse foramen in Indian population

    PubMed Central

    Sureka, Binit; Mittal, Mahesh Kumar; Mittal, Aliza; Agarwal, Mukul Sinha Kanhaiya; Bhambri, Narendra Kumar; Thukral, Brij Bhushan

    2015-01-01

    Purpose: To study the location, origin, size and relationship of the vertebral artery and the transverse foramina in the lower cervical spine by computed tomographic angiography (CTA) measurements in the Indian population. Materials and Methods: A retrospective review of multi-detector CT (MDCT) cerebral angiography scans was done between June 2011 and February 2014. A total of 120 patients were evaluated. The diameter of the vertebral artery (AL) and the shortest distance between the vertebral artery and the medial (M), lateral (L), anterior (A), and posterior (P) borders of transverse foramen were studied. In addition, the shortest distance between the vertebral artery and pedicle (h) was also analyzed. Statistical Analysis: The means and their standard deviations (SD) were calculated in both the sexes. The t-tests were performed to look for significant sexual difference. Results: The largest vertebral artery diameter (AL) was at level C7 on the right side (3.5 ± 0.8) and at the level of C5 on the left side (3.7 ± 0.4). Statistically significant difference between males and females were seen at levels C4, C5, and C7. The diameter of the vertebral artery was smaller in females than males. The L value was greater than other parameters (M, A, P) at the same level in all the measurements. The h value was greatest at C6 level and shortest at C5. Conclusion: CTA is necessary before pedicle screw fixation due to variation in measurements at all levels. The highest potential risk of vertebral artery injury during cervical pedicle screw implantation may be at C5, then at C4, and the safest is at C7. PMID:25969640

  12. Survival, Exercise Capacity, and Left Ventricular Remodeling in a Rat Model of Chronic Mitral Regurgitation: Serial Echocardiography and Pressure-Volume Analysis

    PubMed Central

    Kim, Kyung-Hee; Lee, Seung-Pyo; Kim, Hyung-Kwan; Seo, Jeong-Wook; Sohn, Dae-Won; Oh, Byung-Hee; Park, Young-Bae

    2011-01-01

    Background and Objectives The aims of this study were to establish a reliable model of chronic mitral regurgitation (MR) in rats and verify the pathophysiological features of this model by evaluating cardiac function using serial echocardiography and a pressure-volume analysis. Materials and Methods MR was created in 37 Sprague-Dawley rats by making a hole with a 23 gauge needle on the mitral leaflet through the left ventricular (LV) apex under the guidance of transesophageal echocardiography. Results Serial echocardiograms revealed that the LV began to dilate immediately after the MR operation and showed progressive dilation until the 14th week (LV end-systolic dimension at 14 weeks, 4.71±0.25 mm vs. 6.81±0.50 mm for sham vs. MR, p<0.01; LV end-diastolic dimension, 8.32±0.42 mm vs. 11.01±0.47 mm, p<0.01). The LV ejection fraction tended to increase immediately after the MR operation but started to decrease thereafter and showed a significant difference with the sham group from the 14th week (70.0±2.2% vs. 62.1±3.1% for sham vs. MR). In a pressure-volume analysis performed at the 14th week, the LV end-systolic pressure-volume relationship and +dp/dt decreased significantly in the MR group. A serial treadmill test revealed that exercise capacity remained in the normal range until the 14th week when it began to decrease (exercise duration, 406±45 seconds vs. 330±27 seconds, p<0.01). A pathological analysis showed no significance difference in interstitial fibrosis between the two groups. Conclusion We established a small animal model of chronic MR and verified its pathophysiological features. This model may provide a useful tool for future research on MR and volume overload heart failure. PMID:22125560

  13. Cephalic arterial pattern in New World edentates and Old World pangolins with special reference to their phylogenetic relationships and taxonomy.

    PubMed

    Bugge, J

    1979-01-01

    The cephalic arterial pattern in edentates and pangolins is described on the basis of 9 corrosion specimens, representing all the classical superfamilies, with special reference to their phylogenetic relationship and taxonomy. In this respect, the importance of the manner in which the external carotid artery system annexes the stepedial area of supply and of the course of the internal carotid artery in relation to the tympanic cavity is emphasized. The investigation does not indicate any special relationship between the New World edentates and the Old World pangolins, whereas the marked difference in the course of the internal carotid artery in recent edentates stresses the independent development of the South American anteaters compared with that of the two other edentate groups (armadillos and tree sloths). Most probably the edentates were divided very early into two main lines which have evolved independently since the early Tertiary, i.e. one for the anteaters and one for the tree sloths and armadillos, indicating a probable subdivision of the true edentates into two suborders. This subdivision is markedly different from the classical two-fold division of the edentates.

  14. The effects of acute hypobaric hypoxia on arterial stiffness and endothelial function and its relationship to changes in pulmonary artery pressure and left ventricular diastolic function.

    PubMed

    Boos, C J; Hodkinson, P; Mellor, A; Green, N P; Woods, D R

    2012-06-01

    This study investigated, for the first time, the effects of simulated high altitude, following acute hypobaric hypoxia (HH), on simultaneous assessment of large artery stiffness and endothelial function and its inter-relationship to left ventricular (LV) diastolic function, pulmonary artery systolic pressure (PASP), and estimated PA vascular resistance (PVR). Ten healthy subjects were studied at baseline pre and following acute HH to 4800 m for a total of 180 minutes. Assessments of LV diastolic function, mitral inflow, estimated LV filling pressure (E/e'), PVR, and PASP were undertaken using transthoracic echocardiography. Simultaneous assessments of arterial stiffness index (SI), systemic vascular resistance (SVR), vascular tone, and endothelial function (reflective index [RI]) were performed using pulse contour analysis of the digital arterial waveform. Acute hypoxia led to a fall in SpO₂ (98.1±0.7 vs. 71.8±7.1%; p=0.0002), SVR (1589.1±191.2 vs. 1187.8±248.7; p=0.004), and RI (50.8±10.3 vs. 33.0±6.5%; p=0.0008) with an increase in PASP (24.3±2.2 to 35.0±5.3 mmHg; p=0.0001) and estimated PVR (116.40±19.0 vs. 144.6±21.5; p<0.001). There was no rise in either SI (p=0.13), mitral early annular early e' filling velocity or E/e'. There was a significant inverse correlation between SpO₂ and PASP (r=-0.77; p<0.0001), PVR (r=-0.57; p=0.008) and between the fall in SpO₂ and change (Δ) in RI (baseline vs. 150 min, r=-0.52; p<0.001). There was a modest inverse correlation between ΔRI (lower ΔRI=worsening endothelial function) and ΔPAP (r=-0.55; p=0.10) and a strong inverse correlation between ΔRI and ΔPVR (r=-0.89; p=0.0007). Acute hypobaric hypoxia does not significantly alter large artery stiffness or cause overt LV diastolic function. However, the degree of hypoxia influences both the systemic endothelial and pulmonary vascular responses. This noted association is intriguing and requires further investigation.

  15. The relationship between occupational exposure to lead and manifestation of cardiovascular complications in persons with arterial hypertension

    SciTech Connect

    Poreba, Rafal; Gac, Pawel; Poreba, Malgorzata; Andrzejak, Ryszard

    2010-11-15

    The chronic exposure to lead represents a risk factor of arterial hypertension development. Ambulatory blood pressure monitoring is the most prognostically reliable method of measuring of arterial blood pressure. The study is aimed at evaluating the relationship between occupational exposure to lead and manifestation of cardiovascular complications in patients with arterial hypertension. The studies included 73 men (mean age, 54.26 {+-} 8.17 years) with arterial hypertension, treated with hypotensive drugs: group I-persons occupationally exposed to lead (n = 35) and group II-individuals not exposed to lead (n = 38). An analysis of results obtained during ambulatory blood pressure monitoring disclosed significantly higher values of mean systolic blood pressure, mean blood pressure, pulse pressure, and variability of systolic blood pressure in the group of hypertensive patients occupationally exposed to lead as compared to patients with arterial hypertension but not exposed to lead. The logistic regression showed that a more advanced age, higher concentration of blood zinc protoporphyrin, and a higher mean value of pulse pressure represented independent risk factors of left ventricular hypertrophy in the group of persons with arterial hypertension and chronically exposed to lead (OR{sub age} = 1.11; OR{sub ZnPP} = 1.32; OR{sub PP} = 1,43; p < 0.05). In view of the above data demonstration that occupational exposure to lead represents an independent risk factor of increased pulse pressure may be of key importance in the process of shaping general social awareness as to harmful effects of lead compounds on human health.

  16. [Preliminary analysis of the relationship between peripheral arterial disease and other atherosclerosis markers and diabetic nephropathy].

    PubMed

    Rioja, José; Moreno, Tamara; Coca, Inmaculada; Jiménez-Villodres, Manuel; Rodríguez-Morata, Alejandro; Valdivielso, Pedro

    2014-01-01

    To determine lipid serum levels, lipoproteins and other markers related to nephropathy and peripheral arterial disease (PAD) in a type 2 diabetes population stratified according to their level of renal dysfunction. A cross-sectional study was conducted on 72 type 2 diabetic patients followed-up in outpatient clinics. Patients were divided into 4 groups according to their estimated glomerular filtration rate (eGFR, mL/min) and albumin/creatinine ratio (ACR, mg/g) (eGFR > 60 and ACR < 30 [n = 23], eGFR > 60 and ACR > 30 [n = 12], eGFR30-60 [n = 23] and eGFR < 30 [n = 14]). Clinical and anthropometric characteristic of all patients were recorded. Fasting lipids and apolipoproteins, as well as renal and hematology parameters were measured. Finally, a multivariate Wald stepwise logistic regression statistic analysis was performed to determine variables independently associated with the presence of renal dysfunction. The univariate statistical analysis showed that the higher renal dysfunction, the higher the prevalence of hypertension, smoking habit and triglycerides levels, and the lower hemoglobin levels (P < .05). The multivariate statistical analysis showed that only triglycerides levels (OR: 1.019, 95% CI: 1.004-1.034) and hemoglobin levels (OR: 0.516 95% CI: 0.292-0.914) were independently associated to the presence of renal dysfunction (eGFR < 60 mL/min.). The further inclusion of the presence of PAD in the statistical model did not modify those associations. The results confirm the relationship between triglycerides levels and diabetic nephropathy, independently of the presence of PAD. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  17. U-shaped relationship between insulin level and coronary artery calcification (CAC).

    PubMed

    Tanaka, Muhei; Fukui, Michiaki; Tomiyasu, Ki-ichiro; Akabame, Satoshi; Nakano, Koji; Hasegawa, Goji; Oda, Yohei; Nakamura, Naoto

    2010-10-27

    Recent studies have suggested that hyperinsulinemia is associated with high cardiovascular risk. The purpose of this study was to assess the relationship between the serum insulin level and coronary artery calcification (CAC). We performed a cross-sectional study of 582 consecutive and nondiabetic participants with clinical suspicion of coronary heart disease, and assessed the CAC score determined by multislice computed tomography. A standard 75-g oral glucose tolerance test was performed and venous blood was collected at 0, 30, 60 and 120 min for the measurement of plasma glucose and serum insulin. Statistical analyses were conducted for 4 subgroups according to fasting insulin and insulin area under the concentration time curve (InsAUC). Mean log (CAC+1) and InsAUC were 1.6 and 109.1 µIU/mL, respectively. Unadjusted analysis demonstrated that the fasting insulin quartiles (p=0.0256) and InsAUC quartiles (p<0.0001) were significantly associated with log (CAC+1), and the lowest fasting insulin quartiles (p<0.0001) and the lowest InsAUC quartile (p=0.0006) had lower glucose AUC. Analysis of covariance demonstrated that the lowest InsAUC quartile had the highest log (CAC+1), and the highest InsAUC quartile had a higher log (CAC+1) than the second and third InsAUC quartiles, adjusted for several coronary risk factors (p<0.0001). The lowest InsAUC quartile was related to CAC, although the lowest InsAUC quartile maintained glucose homeostasis, in this study population. Not only hyperinsulinemia but also a low insulin level are independently associated with CAC.

  18. Relationship between epicardial adipose tissue, coronary artery disease and adiponectin in a Mexican population

    PubMed Central

    2014-01-01

    Background The amount of epicardial adipose tissue (EAT) around the heart has been identified as an independent predictor of coronary artery disease (CAD), potentially through local release of inflammatory cytokines. Ethnic differences have been observed, but no studies have investigated this relationship in the Mexican population. The objective of the present study was to evaluate whether a relationship exist between EAT thickness assessed via echocardiography with CAD and adiponectin levels in a Mexican population. Methods We studied 153 consecutive patients who underwent coronary angiography and transthoracic echocardiography (TTE). EAT thickness on the free wall of the right ventricle was measured at the end of systole from parasternal long and short axis views of three consecutive cardiac cycles. Coronary angiograms were analyzed for the presence, extent and severity of CAD. Serum adiponectin, lipids, glucose, C-reactive protein and fibrinogen were determined. Results EAT thickness was greater in patients with CAD than in those without CAD from both parasternal long (5.39 ± 1.75 mm vs 4.00 ± 1.67 mm p < 0.0001) and short-axis views (5.23 ± 1.67 vs 4.12 ± 1.77, p = 0.001). EAT thickness measured from parasternal long and short-axis showed a statistically significant positive correlation with age (r = 0.354, p < 0.001; r = 0.286, p < 0.001 respectively), and waist circumference (r = 0.189, p = 0.019; r = 0.217, p = 0.007 respectively). A significant negative correlation between EAT thickness from the parasternal long axis with cholesterol-HDL was observed (r = -0.163, p = 0.045). No significant correlation was found between epicardial fat thickness and serum adiponectin or with the severity of CAD. Conclusions EAT thickness was greater in patients with CAD. However, no correlation was observed with the severity of the disease or with serum adiponectin levels. EAT thickness measured by

  19. Mapping Regional Differences of Local Pressure-Volume Curves With Electrical Impedance Tomography.

    PubMed

    Beda, Alessandro; Carvalho, Alysson R; Carvalho, Nadja C; Hammermüller, Sören; Amato, Marcelo B P; Muders, Thomas; Gittel, Claudia; Noreikat, Katharina; Wrigge, Hermann; Reske, Andreas W

    2017-04-01

    Lung-protective mechanical ventilation aims to prevent alveolar collapse and overdistension, but reliable bedside methods to quantify them are lacking. We propose a quantitative descriptor of the shape of local pressure-volume curves derived from electrical impedance tomography, for computing maps that highlight the presence and location of regions of presumed tidal recruitment (i.e., elastance decrease during inflation, pressure-volume curve with upward curvature) or overdistension (i.e., elastance increase during inflation, downward curvature). Secondary analysis of experimental cohort study. University research facility. Twelve mechanically ventilated pigs. After induction of acute respiratory distress syndrome by hydrochloric acid instillation, animals underwent a decremental positive end-expiratory pressure titration (steps of 2 cm H2O starting from ≥ 26 cm H2O). Electrical impedance tomography-derived maps were computed at each positive end-expiratory pressure-titration step, and whole-lung CT taken every second steps. Airway flow and pressure were recorded to compute driving pressure and elastance. Significant correlations between electrical impedance tomography-derived maps and positive end-expiratory pressure indicate that, expectedly, tidal recruitment increases in dependent regions with decreasing positive end-expiratory pressure (p < 0.001) and suggest that overdistension increases both at high and low positive end-expiratory pressures in nondependent regions (p < 0.027), supporting the idea of two different scenarios of overdistension occurrence. Significant correlations with CT measurements were observed: electrical impedance tomography-derived tidal recruitment with poorly aerated regions (r = 0.43; p < 0.001); electrical impedance tomography-derived overdistension with nonaerated regions at lower positive end-expiratory pressures and with hyperaerated regions at higher positive end-expiratory pressures (r ≥ 0.72; p < 0.003). Even for

  20. Relationship between intracranial hypertension and ultrasonic patterns of the common carotid artery and the internal jugular vein.

    PubMed

    Liboni, W; Bertolotto, A; Urciuoli, R

    1983-01-01

    The Doppler technique has only been used in neurological practice to evidence local vessel pathology such as occlusion or stenosis. Both common carotid artery and internal jugular vein flows can change not only because of pathological processes of the vessels but also because of impedance of their distribution territory. In this report we analyze the relationship between flow velocity, one of the parameters of blood flow, and intracranial impedance variations which occur in cerebral concussion, tumors and acute vascular cerebral pathology. During our observations we noticed that the diastolic wave of the velocity curve of the common carotid artery is a very important signal of the flow variations in the internal carotid artery and, in turn, of variations in cerebral flow. We studied the behaviour of the common carotid artery velocity curve in our patients both during clinical disease development and during the action of mannitol in the acute phases of the disease. We found that the ultrasonic patterns during antiedema action were similar to the ones obtained during the recovery period. We were able to note some differences and some similarities of the curve morphology in relation to generalized or focal causes of cerebral edema. This may be very important considering that at present no non-invasive and therefore repeatable technique is available for monitoring cerebral blood flow in intracranial hypertension.

  1. Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? Yes.

    PubMed

    Paulus, Jessica K; Thaler, David E

    2016-01-01

    For patients and health care providers who are considering spinal manipulative therapy of the neck, it is crucial to establish if it is a trigger for cervical artery dissection and/or stroke, and if it is, the magnitude of the risk. We discuss the biological plausibility of how neck manipulation could cause cervical artery dissection. We also discuss how case misclassification threatens the validity of influential published studies that have investigated the relationship between neck manipulation and dissection. Our position is supported by the fact that the largest epidemiologic studies of neck manipulation safety with respect to neurological outcomes have relied on International Classification of Diseases-9 codes for case identification. However, the application of these codes in prior studies failed to identify dissections (rather than strokes in general) and so conclusions from those studies are invalid. There are several methodological challenges to understanding the association between neck manipulation and vertebral artery dissection. Addressing these issues is critical because even a modest association between neck manipulation and cervical artery dissection could translate into a significant number of avoidable dissections given the widespread use of neck manipulation by providers from various backgrounds. We believe that valid case classification, accurate measurement of manipulative procedures, and addressing reverse causation bias should be top priorities for future research.

  2. Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? No.

    PubMed

    Murphy, Donald R; Schneider, Michael J; Perle, Stephen M; Bise, Christopher G; Timko, Michael; Haas, Mitchell

    2016-01-01

    The purported relationship between cervical manipulative therapy (CMT) and stroke related to vertebral artery dissection (VAD) has been debated for several decades. A large number of publications, from case reports to case-control studies, have investigated this relationship. A recent article suggested that case misclassification in the case-control studies on this topic resulted in biased odds ratios in those studies. Given its rarity, the best epidemiologic research design for investigating the relationship between CMT and VAD is the case-control study. The addition of a case-crossover aspect further strengthens the scientific rigor of such studies by reducing bias. The most recent studies investigating the relationship between CMT and VAD indicate that the relationship is not causal. In fact, a comparable relationship between vertebral artery-related stroke and visits to a primary care physician has been observed. The statistical association between visits to chiropractors and VAD can best be explained as resulting from a patient with early manifestation of VAD (neck pain with or without headache) seeking the services of a chiropractor for relief of this pain. Sometime after the visit the patient experiences VAD-related stroke that would have occurred regardless of the care received. This explanation has been challenged by a recent article putting forth the argument that case misclassification is likely to have biased the odds ratios of the case-control studies that have investigated the association between CMT and vertebral artery related stroke. The challenge particularly focused on one of the case-control studies, which had concluded that the association between CMT and vertebral artery related stroke was not causal. It was suggested by the authors of the recent article that misclassification led to an underestimation of risk. We argue that the information presented in that article does not support the authors' claim for a variety of reasons, including the

  3. Pressure-Volume-Temperature Behavior of Hyperbranched Polyols: Experiment and Modelling

    NASA Astrophysics Data System (ADS)

    Kaushik, Mukul; Nazarenko, Sergei; Olson, Brian

    2011-03-01

    The pressure volume temperature behavior of two generations of hyperbranched polyesters Boltorn TM H40 and H20 was studied by PVT measurements using high pressure dilatometer. Volumetric expansivity, and free volume parameters were determined for both generations in the melt state. The PVT data were fitted to Simha-Somcynsky (SS) equation of state (EOS) and Sanchez--Lacombe (SL) equation of state (EOS) to calculate occupied volume and fractional free volume. The values of occupied volume and fractional free volumes obtained through both the equations of states were similar. Simulated atmospheric pressure V-T data were generated by using Discover module of Accelrys. Quality of equilibrium was confirmed by energy stabilization and closeness of experimental and simulation densities. WAXD and temperature-volume curves obtained by molecular dynamics simulations were comparable to the experimental data. Well relaxed amorphous cell was further utilized to study hydrogen bond network and determination of O-O pair correlation function of terminal hydroxyl groups.

  4. Leaf Pressure Volume Data in Caxiuana and Tapajos National Forest, Para, Brazil (2011)

    SciTech Connect

    Powell, Thomas; Moorcroft, Paul

    2017-01-01

    Pressure volume curve measurements on leaves of canopy trees from the from the Caxiuana and Tapajos National Forests, Para, Brazil. Tapajos samples were harvested from the km 67 forested area, which is adjacent to the decommissioned throughfall exclusion drought experimental plot. Caxiuana samples were harvested from trees growing in the throughfall exclusion plots. Data were collected in 2011. Dataset includes: date of measurement, site ID, plot ID, tree ID (species, tree tag #), leaf area, fresh weight, relative weight, leaf water potential, and leaf water loss. P-V curve parameters (turgor loss point, osmotic potential, and bulk modulus of elasticity) can be found in Powell et al. (2017) Differences in xylem cavitation resistance and leaf hydraulic traits explain differences in drought tolerance among mature Amazon rainforest trees. Global Change Biology.

  5. [Pressure-volume analysis of wound suction drainage containers and suction capacity of drainage tubes].

    PubMed

    Mohadjer, C; Siegert, R; Jäger, H; Weidauer, H

    1994-01-01

    Four low-vacuum systems and eight high-vacuum systems were examined with special reference to the pressure-volume relations. The maximum filling volume for adequate transport of wound secretion was determined for each type. The use of a synthetic wound fluid instead of water resulted in a smaller aspiration volume. Enlargement of the tube diameter resulted in a reduced initial vacuum for the low-vacuum systems, whereas the high-vacuum systems were not affected. Normal drain tubes were compared with "Ulm drains" and silicon tubes for suction capacity. The suction maximum of normal tubes and silicon tubes was located at the proximal holes of the perforated tubes. The "Ulm drain," with perforation diameter increasing continuously to the distal end of the tube, was found to exert suction even at the more distal part of the tube. It is estimated that this tube allows locally more balanced vacuum in the wound.

  6. Multipoint determination of pressure-volume curves in human intervertebral discs.

    PubMed Central

    Ranu, H S

    1993-01-01

    To gain further insight into the biomechanics of the human intervertebral disc and to determine a potential mechanism for causation and relief of symptoms related to a herniated disc, the pressure-volume relation was determined within the nucleus pulposus. Pressure was measured continuously within the nucleus pulposus in 17 intact lumbar discs from human cadavers by means of a miniature strain gauge at the tip of a size 4 French (1.3 mm) catheter inserted into the nucleus pulposus. The volume of the nucleus pulposus was increased at the slow, continuous rate of 0.034 ml/min by the pump regulated infusion of saline coloured with methylene blue. In 12 unloaded discs, nucleus pulposus pressure rose in a linear fashion (linear r = 0.96) from an initial mean pressure of 174 (SD 81) kPa. The mean rate of pressure rise was 327 (SD 109) kPa/ml volume increase. The peak pressure measured was 550 kPa; this was slightly higher than the capability of the transducer. Similar linear relations were obtained during infusion of saline into five vertically loaded discs fixed at the deformation produced by a 9.1 kg weight. The data define the pressure-volume relation within the disc and show that the nucleus pulposus, surrounded by the relatively inelastic annulus and the solid vertebral end plates, has the properties of a tight hydraulic space in which a large pressure rise will regularly result from a small increase in volume. Presumably the opposite is also true. The data may provide a biomechanical basis for the physiological variation in symptoms related to the disc, and for any benefits obtained from interventions designed to remove disc tissue. PMID:8447694

  7. The Temporal Relationship between Arterial Stiffening and Blood Pressure Is Modified by Methotrexate Treatment in Patients with Rheumatoid Arthritis.

    PubMed

    Woodman, Richard J; Baghdadi, Leena R; Shanahan, Michael E; Mangoni, Arduino A

    2017-01-01

    Background: The temporal relationship between arterial stiffness and blood pressure (BP) may vary depending on age and other clinical and demographic factors. Since both BP and arterial stiffness are also affected by inflammatory processes, we examined the temporal arterial stiffness-BP relationship in patients with rheumatoid arthritis (RA) treated with either methotrexate (MTX), an anti-rheumatic agent shown to reduce cardiovascular risk in meta-analyses, or other disease-modifying anti-rheumatic drugs (DMARDs). Methods: Measurements of clinic and 24-h peripheral and central systolic and diastolic BP (SBP and DBP), and pulse wave velocity (PWV) were assessed in RA patients on stable treatment with either MTX ± other DMARDs (MTX group, n = 41, age 61 ± 14 years, 73% females) or other DMARDs (non-MTX group, n = 18, age 65 ± 13 years, 89% females). Measurements were performed at baseline and after 8 months. The temporal relationships were examined using cross-lagged path analysis with models that included age, sex, body mass index, prednisolone, and folic acid use and 28-joint disease activity score. Results: There were significant differences in the temporal arterial stiffness-BP relationships between those in the MTX and DMARD groups. A higher PWV at baseline caused a significant increase in 6 out of 8 different measures of SBP at 8 months amongst those treated with DMARDs (standardized β, range = 0.54-0.66, p < 0.003 for each) and 3 out of 8 different measures of DBP (standardized β, range = 0.52-0.61, p < 0.003 for each) but was not associated with either SBP or DBP at 8 months amongst those treated with MTX. The difference in the effect of baseline PWV on 8-month BP between the 2 groups was also significant (p < 0.003) for 4 measures including clinic peripheral SBP (β = 7.0, 95% CI = 2.8-11.1 mmHg per 1 m/s higher baseline PWV; p < 0.001). Conclusions: Higher arterial stiffness preceded increases in BP in subjects with RA treated with DMARDs, but these

  8. Relationship between nitroglycerine-induced vasodilation and clinical severity of peripheral artery disease.

    PubMed

    Maruhashi, Tatsuya; Nakashima, Ayumu; Matsumoto, Takeshi; Oda, Nozomu; Iwamoto, Yumiko; Iwamoto, Akimichi; Kajikawa, Masato; Kihara, Yasuki; Chayama, Kazuaki; Goto, Chikara; Noma, Kensuke; Higashi, Yukihito

    2014-07-01

    Nitroglycerine-induced vasodilation is usually used as a control test for flow-mediated vasodilation (FMD). However, nitroglycerine-induced vasodilation per se has also been reported to be impaired in patients with atherosclerosis. The purpose of this study was to determine the relationship between nitroglycerine-induced vasodilation and the clinical severity of peripheral artery disease (PAD). We measured nitroglycerine-induced vasodilation and FMD in 144 subjects (mean age: 63.8 ± 15.1 years), including 32 PAD patients with critical limb ischemia (CLI group), 28 PAD patients without CLI (non-CLI group), 60 age- and sex-matched patients without established cardiovascular disease (at-risk group), and 24 healthy subjects (healthy group). Nitroglycerine-induced vasodilation was significantly impaired in the CLI group compared to that in the other three groups (healthy group, 16.0 ± 5.3%; at-risk group, 12.9 ± 3.8%; non-CLI group, 10.3 ± 5.1%; CLI group, 6.7 ± 3.9%; P < 0.05, respectively). Even after multivariate adjustment, the differences remained significant. On the other hand, FMD was significantly impaired in the at-risk, non-CLI, and CLI group compared with that in the healthy group (healthy group, 7.1 ± 2.9%; at-risk group, 3.4 ± 2.3%; non-CLI group, 3.5 ± 2.7%; CLI group, 3.0 ± 2.8%; P < 0.001, respectively), but the differences among the at-risk, non-CLI, and CLI groups were not significant. Multivariate analysis revealed that nitroglycerine-induced vasodilation (odds ratio: 0.77, 95% confidence interval [CI]: 0.61-0.97) and diabetes mellitus (odds ratio: 8.75, 95% CI: 1.74-44.2) were independent variables for CLI in PAD patients. There was no significant difference in FMD between PAD patients with and those without CLI, but nitroglycerine-induced vasodilation was significantly smaller in PAD patients with CLI compared with those without CLI. Copyright © 2014. Published by Elsevier Ireland Ltd.

  9. Mean Platelet Volume and Arterial Stiffness – Clinical Relationship and Common Genetic Variability

    PubMed Central

    Panova-Noeva, Marina; Arnold, Natalie; Hermanns, M. Iris; Prochaska, Jürgen H.; Schulz, Andreas; Spronk, Henri M.; Binder, Harald; Pfeiffer, Norbert; Beutel, Manfred; Blankenberg, Stefan; Zeller, Tanja; Lotz, Johannes; Münzel, Thomas; Lackner, Karl J.; ten Cate, Hugo; Wild, Philipp S.

    2017-01-01

    Vessel wall stiffening is an important clinical parameter, but it is unknown whether platelets, key elements in the pathogenesis of arterial thrombosis, are associated with arterial stiffness. The present studies sought to determine whether mean platelet volume (MPV), a potential marker of platelet activation, is linked to vascular elasticity as assessed by the augmentation index (AIx), in 15,010 individuals from the population-based Gutenberg Health Study. Multivariable analysis showed that MPV in both males (β 0.776; 95thCI [0.250;1.16]; p = 0.0024) and females (β 0.881[0.328;1.43]; p = 0.0018) is strongly associated with AIx. Individuals with MPV and AIx above the sex-specific medians had worse survival. Association analysis between MPV-related genetic variants and arterial stiffness identified four genetic variants in males and one in females related with AIx. Cox regression analysis for mortality identified one of these joint genetic variants close to ring finger protein 145 gene (RNF145, rs10076782) linked with increased mortality (hazard ratio 2.02; 95thCI [1.35;3.02]; p = 0.00061). Thus, these population-based data demonstrate a close relation between platelet volume as a potential marker of platelet activation and arterial stiffness in both sexes. Further research is warranted to further elucidate the mechanisms underlying larger platelets‘ role in arterial stiffening including the role of shared common genetics. PMID:28059166

  10. Variations in the Origin of Inferior Phrenic Arteries and Their Relationship to Celiac Axis Variations on CT Angiography

    PubMed Central

    Aslaner, Ramazan; Sahin, Hilal; Toka, Onur

    2017-01-01

    Objective Knowing the origin of the inferior phrenic artery (IPA) is important prior to surgical interventions and interventional radiological procedures related to IPA. We aimed to identify variations in the origin of IPA and to investigate the relationship between the origin of IPA and celiac axis variations using computed tomography angiography (CTA). Materials and Methods The CTA images of 1000 patients (737 male and 263 female, the mean age 60, range 18–94 years) were reviewed in an analysis of IPA and celiac axis variations. The origin of IPA was divided into two groups, those originating as a common trunk and those originating independently without a truncus. The relationship between the origin of IPA and celiac axis variation was analyzed using Pearson's chi-square test. Results Both IPAs originated from a common trunk in 295 (29.5%) patients. From which the majority of the common trunk originated from the aorta. Contrastingly, the inferior phrenic arteries originated from different origins in 705 (70.5%) patients. The majority of the right inferior phrenic artery (RIPA) and the left inferior phrenic artery (LIPA) originated independently from the celiac axis. Variation in the celiac axis were detected in 110 (11%) patients. The origin of IPA was found to be significantly different in the presence of celiac axis variation. Conclusion The majority of IPA originated from the aorta in patients with a common IPA trunk, while the majority of RIPA and LIPA originating from the celiac axis in patients without a common IPA trunk. Thus, the origin of IPA may widely differ in the presence of celiac axis variation. PMID:28246513

  11. Variations in the Origin of Inferior Phrenic Arteries and Their Relationship to Celiac Axis Variations on CT Angiography.

    PubMed

    Aslaner, Ramazan; Pekcevik, Yeliz; Sahin, Hilal; Toka, Onur

    2017-01-01

    Knowing the origin of the inferior phrenic artery (IPA) is important prior to surgical interventions and interventional radiological procedures related to IPA. We aimed to identify variations in the origin of IPA and to investigate the relationship between the origin of IPA and celiac axis variations using computed tomography angiography (CTA). The CTA images of 1000 patients (737 male and 263 female, the mean age 60, range 18-94 years) were reviewed in an analysis of IPA and celiac axis variations. The origin of IPA was divided into two groups, those originating as a common trunk and those originating independently without a truncus. The relationship between the origin of IPA and celiac axis variation was analyzed using Pearson's chi-square test. Both IPAs originated from a common trunk in 295 (29.5%) patients. From which the majority of the common trunk originated from the aorta. Contrastingly, the inferior phrenic arteries originated from different origins in 705 (70.5%) patients. The majority of the right inferior phrenic artery (RIPA) and the left inferior phrenic artery (LIPA) originated independently from the celiac axis. Variation in the celiac axis were detected in 110 (11%) patients. The origin of IPA was found to be significantly different in the presence of celiac axis variation. The majority of IPA originated from the aorta in patients with a common IPA trunk, while the majority of RIPA and LIPA originating from the celiac axis in patients without a common IPA trunk. Thus, the origin of IPA may widely differ in the presence of celiac axis variation.

  12. Relationship Between Measures of Adiposity, Arterial Inflammation, and Subsequent Cardiovascular Events

    PubMed Central

    Figueroa, Amparo L.; Takx, Richard A. P.; MacNabb, Megan H.; Abdelbaky, Amr; Lavender, Zachary R.; Kaplan, Rebecca S.; Truong, Quynh A.; Lo, Janet; Ghoshhajra, Brian B.; Grinspoon, Steven K.; Hoffmann, Udo; Tawakol, Ahmed

    2016-01-01

    Background The objective of this study was to evaluate how different measures of adiposity are related to both arterial inflammation and the risk of subsequent cardiovascular events. Methods and Results We included individuals who underwent FDG PET/CT imaging for oncological evaluation. Subcutaneous adipose tissue (SAT) volume, visceral adipose tissue (VAT) volume and VAT/SAT ratio were determined. Additionally BMI, metabolic syndrome (MetS), and, aortic FDG uptake (a measure of arterial inflammation) were determined. Subsequent development of cardiovascular disease (CVD) events was adjudicated. The analysis included 415 patients with a median age of 55 (P25–P75: 45–65) and a median BMI of 26.4 (P25– P75: 23.4–30.9) kg/m2. VAT and SAT volume were significantly higher in obese individuals. VAT volume (r=0.290, p<0.001) and VAT/SAT ratio (r=0.208, p<0.001) were positively correlated with arterial inflammation. 32 subjects experienced CVD event during a median follow-up of 4 years. Cox proportional hazard models showed that VAT volume, and VAT/SAT ratio were associated with CVD events (hazard ratio, HR (95% CI): 1.15 (1.06–1.25, p<0.001; 3.60 (1.88–6.92), p<0.001 respectively). BMI, MetS and SAT were not predictive of CVD events. Conclusions Measures of visceral fat are positively related to arterial inflammation and are independent predictors of subsequent CVD events. Individuals with higher measures of visceral fat as well as elevated arterial inflammation are at highest risk for subsequent CVD events. The findings suggest that arterial inflammation may explain some of the CVD risk associated with adiposity. PMID:27072302

  13. Relationship Between Measures of Adiposity, Arterial Inflammation, and Subsequent Cardiovascular Events.

    PubMed

    Figueroa, Amparo L; Takx, Richard A P; MacNabb, Megan H; Abdelbaky, Amr; Lavender, Zachary R; Kaplan, Rebecca S; Truong, Quynh A; Lo, Janet; Ghoshhajra, Brian B; Grinspoon, Steven K; Hoffmann, Udo; Tawakol, Ahmed

    2016-04-01

    The objective of this study was to evaluate how different measures of adiposity are related to both arterial inflammation and the risk of subsequent cardiovascular events. We included individuals who underwent (18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging for oncological evaluation. Subcutaneous adipose tissue (SAT) volume, visceral adipose tissue (VAT) volume, and VAT/SAT ratio were determined. Additionally, body mass index, metabolic syndrome, and aortic (18)F-fluorodeoxyglucose uptake (a measure of arterial inflammation) were determined. Subsequent development of cardiovascular disease (CVD) events was adjudicated. The analysis included 415 patients with a median age of 55 (P25-P75: 45-65) and a median body mass index of 26.4 (P25-P75: 23.4-30.9) kg/m(2). VAT and SAT volume were significantly higher in obese individuals. VAT volume (r=0.290; P<0.001) and VAT/SAT ratio (r=0.208; P<0.001) were positively correlated with arterial inflammation. Thirty-two subjects experienced a CVD event during a median follow-up of 4 years. Cox proportional hazard models showed that VAT volume and VAT/SAT ratio were associated with CVD events (hazard ratio [95% confidence interval]: 1.15 [1.06-1.25]; P<0.001; 3.60 [1.88-6.92]; P<0.001, respectively). Body mass index, metabolic syndrome, and SAT were not predictive of CVD events. Measures of visceral fat are positively related to arterial inflammation and are independent predictors of subsequent CVD events. Individuals with higher measures of visceral fat as well as elevated arterial inflammation are at highest risk for subsequent CVD events. The findings suggest that arterial inflammation may explain some of the CVD risk associated with adiposity. © 2016 American Heart Association, Inc.

  14. Left ventricular pressure-volume measurements and myocardial gene expression profile in type 2 diabetic Goto-Kakizaki rats.

    PubMed

    Korkmaz-Icöz, Sevil; Lehner, Alice; Li, Shiliang; Vater, Adrian; Radovits, Tamás; Brune, Maik; Ruppert, Mihály; Sun, Xiaoxin; Brlecic, Paige; Zorn, Markus; Karck, Matthias; Szabó, Gábor

    2016-10-01

    The Goto-Kakizaki (GK) rat, a non-obese model of type 2 diabetes mellitus (T2DM), was generated by the selective inbreeding of glucose-intolerant Wistar rats. This is a convenient model for studying diabetes-induced cardiomyopathy independently from the effects of the metabolic syndrome. We investigated the myocardial functional and structural changes and underlying molecular pathomechanisms of short-term and mild T2DM. The presence of DM was confirmed by an impaired oral glucose tolerance in the GK rats compared with the age-matched nondiabetic Wistar rats. Data from cardiac catheterization showed that in GK rats, although the systolic indexes were not altered, the diastolic stiffness was increased compared with nondiabetics (end-diastolic-pressure-volume-relationship: 0.12 ± 0.04 vs. 0.05 ± 0.01 mmHg/μl, P < 0.05). Additionally, DM was associated with left-ventricular hypertrophy and histological evidence of increased myocardial fibrosis. The plasma pro-B-type natriuretic peptide, the cardiac troponin-T, glucose, and the urinary glucose concentrations were significantly higher in GK rats. Among the 125 genes surveyed using PCR arrays, DM significantly altered the expression of five genes [upregulation of natriuretic peptide precursor-A and connective tissue growth factor, downregulation of c-reactive protein, interleukin-1β, and tumor necrosis factor (TNF)-α mRNA-level]. Of the altered genes, which were evaluated by Western blot, only TNF-α protein expression was significantly decreased. The ECG recordings revealed no significant differences. In conclusion, while systolic dysfunction, myocardial inflammation, and abnormal electrical conduction remain absent, short-term and mild T2DM induce the alteration of cardiac TNF-α at both the mRNA and protein levels. Further assessments are required to reveal if TNF-α plays a role in the early stage of diabetic cardiomyopathy development. Copyright © 2016 the American Physiological Society.

  15. Relationship between carotid intima‐media thickness and arterial stiffness in children after Kawasaki disease

    PubMed Central

    Cheung, Y‐f; Wong, S J; Ho, M H K

    2007-01-01

    Background Evidence of premature atherosclerosis and systemic arterial stiffening in patients after Kawasaki disease is accumulating. Aim To test the hypothesis that carotid intima‐media thickness (IMT), a surrogate marker of atherosclerosis, is associated with systemic arterial stiffness in children after Kawasaki disease. Methods A cohort of 72 patients was studied, comprising 26 patients with Kawasaki disease and coronary aneurysms (group I), 24 patients with Kawasaki disease and normal coronary arteries (group II) and 22 healthy age‐matched children (group III). The carotid IMT, carotid artery stiffness index, brachioradial pulse wave velocity (PWV), fasting total cholesterol, high‐density lipoprotein (HDL) cholesterol and low‐density lipoprotein (LDL) cholesterol were determined and compared among the three groups. Results The carotid IMT was related to indices of arterial stiffness, and significant determinants of carotid IMT were identified by multivariate analysis. The mean (standard deviation (SD)) carotid IMT of both group I (0.41 (0.04) mm) and group II (0.39 (0.04) mm) was significantly greater than that of group III (0.36 (0.04) mm; p<0.001 and p = 0.008, respectively). For the entire cohort, carotid IMT correlated positively with LDL cholesterol (r = 0.31, p = 0.009), carotid artery stiffness index (r = 0.40, p = 0.001) and brachioradial PWV (r = 0.28, p = 0.016), but not with age, body mass index, systemic blood pressure, and HDL and total cholesterol. Multiple linear regression analysis identified carotid artery stiffness index (β = 0.25, p = 0.028) and subject grouping (β = −0.39, p = 0.001; model R2 = 0.29) as significant correlates of carotid IMT. Conclusion The increased carotid IMT in children after Kawasaki disease is associated with systemic arterial stiffening. PMID:16820386

  16. 3D Real-Time Echocardiography Combined with Mini Pressure Wire Generate Reliable Pressure-Volume Loops in Small Hearts

    PubMed Central

    Linden, Katharina; Dewald, Oliver; Gatzweiler, Eva; Seehase, Matthias; Duerr, Georg Daniel; Dörner, Jonas; Kleppe, Stephanie

    2016-01-01

    Background Pressure-volume loops (PVL) provide vital information regarding ventricular performance and pathophysiology in cardiac disease. Unfortunately, acquisition of PVL by conductance technology is not feasible in neonates and small children due to the available human catheter size and resulting invasiveness. The aim of the study was to validate the accuracy of PVL in small hearts using volume data obtained by real-time three-dimensional echocardiography (3DE) and simultaneously acquired pressure data. Methods In 17 piglets (weight range: 3.6–8.0 kg) left ventricular PVL were generated by 3DE and simultaneous recordings of ventricular pressure using a mini pressure wire (PVL3D). PVL3D were compared to conductance catheter measurements (PVLCond) under various hemodynamic conditions (baseline, alpha-adrenergic stimulation with phenylephrine, beta-adrenoreceptor-blockage using esmolol). In order to validate the accuracy of 3D volumetric data, cardiac magnetic resonance imaging (CMR) was performed in another 8 piglets. Results Correlation between CMR- and 3DE-derived volumes was good (enddiastolic volume: mean bias -0.03ml ±1.34ml). Computation of PVL3D in small hearts was feasible and comparable to results obtained by conductance technology. Bland-Altman analysis showed a low bias between PVL3D and PVLCond. Systolic and diastolic parameters were closely associated (Intraclass-Correlation Coefficient for: systolic myocardial elastance 0.95, arterial elastance 0.93, diastolic relaxation constant tau 0.90, indexed end-diastolic volume 0.98). Hemodynamic changes under different conditions were well detected by both methods (ICC 0.82 to 0.98). Inter- and intra-observer coefficients of variation were below 5% for all parameters. Conclusions PVL3D generated from 3DE combined with mini pressure wire represent a novel, feasible and reliable method to assess different hemodynamic conditions of cardiac function in hearts comparable to neonate and infant size. This

  17. A constitutive modeling interpretation of the relationship among carotid artery stiffness, blood pressure, and age in hypertensive subjects.

    PubMed

    Spronck, Bart; Heusinkveld, Maarten H G; Donders, Wouter P; de Lepper, Anouk G W; Op't Roodt, Jos; Kroon, Abraham A; Delhaas, Tammo; Reesink, Koen D

    2015-03-15

    Aging has a profound influence on arterial wall structure and function. We have previously reported the relationship among pulse wave velocity, age, and blood pressure in hypertensive subjects. In the present study, we aimed for a quantitative interpretation of the observed changes in wall behavior with age using a constitutive modeling approach. We implemented a model of arterial wall biomechanics and fitted this to the group-averaged pressure-area (P-A) relationship of the "young" subgroup of our study population. Using this model as our take-off point, we assessed which parameters had to be changed to let the model describe the "old" subgroup's P-A relationship. We allowed elastin stiffness and collagen recruitment parameters to vary and adjusted residual stress parameters according to published age-related changes. We required wall stress to be homogeneously distributed over the arterial wall and assumed wall stress normalization with age by keeping average "old" wall stress at the "young" level. Additionally, we required axial force to remain constant over the cardiac cycle. Our simulations showed an age-related shift in pressure-load bearing from elastin to collagen, caused by a decrease in elastin stiffness and a considerable increase in collagen recruitment. Correspondingly, simulated diameter and wall thickness increased by about 20 and 17%, respectively. The latter compared well with a measured thickness increase of 21%. We conclude that the physiologically realistic changes in constitutive properties we found under physiological constraints with respect to wall stress could well explain the influence of aging in the stiffness-pressure-age pattern observed.

  18. Relationship between red cell distribution width levels and severity of coronary artery ectasia.

    PubMed

    Keser, A; Özbek, K; Ulucan, Ş; Katlandur, H; Bilgi, M; Özdil, H

    2016-04-01

    Coronary artery ectasia (CAE) is defined as abnormal dilatation of coronary arteries. Inflammation is thought to be important in the pathogenesis of CAE. Red blood cell distribution width (RDW) is also an inflammatory marker. In this study, we examined the association between RDW levels and CAE severity. A total of 6737 patients who were admitted to the Cardiology Clinic of our hospital between January 2010 and December 2015 and diagnosed with coronary artery disease (CAD) were evaluated for inclusion. Of them, 126 patients who had CAE as a result of retrospective scanning, 104 randomly selected patients with CAD, and 76 patients who had normal coronary arteries were included in the study (n = 306). The severity and prevalence of CAE were evaluated according to the Markis ectasia classification, and the RDW value for type 1 CAE was significantly higher than that of other types of CAE. The RDW values for types 1-4 were 19.48 ± 11.81, 15.26 ± 9.17, 15.51 ± 8.07, and 15.33 ± 7.26, respectively (p= 0.098; r = 0.114). High RDW values are associated with CAE and CAD, and correlate with the severity of CAE. These findings indicate that RDW values can be used to estimate the severity of CAE disease.

  19. Commonality Study of the Pressure-Volume-Temperature Based Propellant Gaging Software Modules for the Auxiliary Power Unit, Reaction Control System, and Orbital Maneuvering System

    NASA Technical Reports Server (NTRS)

    Duhon, D. D.

    1975-01-01

    Computer storage requirements can be reduced if areas of commonality exist in two or more programs placed in the same computer and identical code can be used by more than one program. The pressure-volume-temperature (P-V-T) relationship for the propellant tank pressurant agent is utilized as the basis for either a primary of a backup propellant gaging program for the auxiliary power unit (APU), the reaction control system (RCS), and the orbital maneuvering system (OMS). These three propellant gaging programs were investigated. It was revealed that a very limited degree of software commonality exits among them. An examination of this common software indicated that only the computation of the helium compressibility factor in an external function subprogram accessible to both the RCS and OMS propellant gaging programs appears to offer a savings in computer storage requirements.

  20. Mean platelet volume in patients with metabolic syndrome and its relationship with coronary artery disease.

    PubMed

    Tavil, Yusuf; Sen, Nihat; Yazici, Hüseyin Uğur; Hizal, Fatma; Abaci, Adnan; Cengel, Atiye

    2007-01-01

    Mean platelet volume (MPV) is an indicator of platelet activation which is a central process in the pathophysiology of coronary heart disease. The metabolic syndrome (MS) is characterized as the clustering of closely associated and interdependent atherosclerotic risk factors. MS has also been shown to be strongly associated with poor outcome in patients with coronary artery disease (CAD). The present study was designed to investigate MPV values in patients MS and to interrogate the association with CAD. We measured MPV in 205 consecutive patients with metabolic syndrome (mean age, 53+/-7 years) and 140 control subjects without metabolic syndrome (mean age, 52+/-6 years). All patients were selected from individuals who underwent coronary angiography in our hospital with a suspicion of coronary artery disease. To evaluate the severity of coronary artery disease, the patients with MS were subdivided depending upon the coexistence of coronary artery disease: normal coronary arteries, having coronary stenotic lesions of <50%, and having coronary stenotic lesions of >50%. The MPV was significantly higher in patients with MS than in the control group (10.19+/-1.49 fl vs 8.21+/-1.02 fl, p<0.001). According to the CAD severity, there were no statistically significant differences in MPV among these subgroups. We have shown for the first time that patients with MS have higher MPV compared to control subjects with normal coronary angiograms and to be associated with CAD. Hence MPV can be used as a follow up marker in patients with MS in the point of CAD.

  1. Relationship between glycaemic levels and arterial stiffness in non-diabetic adults.

    PubMed

    Cavero-Redondo, Iván; Martínez-Vizcaíno, Vicente; Álvarez-Bueno, Celia; Recio-Rodríguez, José Ignacio; Gómez-Marcos, Manuel Ángel; García-Ortiz, Luis

    2017-09-15

    To examine, in a non-diabetic population, whether the association between arterial stiffness and glycaemic levels depends on the test used as a glycaemic indicator, fasting plasma glucose (FPG) or glycated haemoglobin A1c (HbA1c). A cross-sectional analysis of a 220 non-diabetic subsample from the EVIDENT II study in which FPG, HbA1c and arterial stiffness-related parameters (pulse wave velocity, radial and central augmentation index, and central pulse pressure) were determined. Mean differences in arterial stiffness-related parameters by HbA1c and FPG tertiles were tested using analysis of covariance. All means of arterial stiffness-related parameters increased by HbA1c tertiles, although mean differences were only statistically significant in pulse wave velocity (p ≤.001), even after controlling for potential confounders (HbA1c <5.30% = 6.88 m/s; HbA1c 5.30%-5.59% = 7.06 m/s; and HbA1c ≥5.60% = 8.16 m/s, p =.004). Conversely, mean differences in pulse wave velocity by FPG tertiles did not reach statistically significant differences after controlling for potential confounders (FPG 4.44 mmol/l = 7.18 m/s; FPG 4.44 mmol/l-4.87 mmol/l = 7.26 m/s; and FPG ≥4.88 mmol/l = 7.93 m/s, p =.066). Glucose levels in a non-diabetic population were associated with arterial stiffness but better when levels were determined using HbA1c. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  2. Relationship between pulmonary arterial pressure and pulmonary thromboembolism associated with dead worms in canine heartworm disease.

    PubMed

    Hirano, Y; Kitagawa, H; Sasaki, Y

    1992-10-01

    To examine effects of thromboemboli due to dead worms on pulmonary arterial pressure (PAP), 20 to 50 dead heartworms were inserted into the pulmonary arteries of 4 heartworm uninfected dogs (uninfected group) and 11 dogs infected with heartworms (infected group). In the uninfected group, the mean PAP rose 1 week after worm insertion (10.9 to 166. mmHg), but it recovered by the 4th week. Clinical signs, hemodynamics and blood gas findings also deteriorated at the 1st week, but recovered at the 4th week. Angiographic and pathological findings indicated that blood flow recovered through the spaces between thromboemboli and vessel walls at the 4th week. The infected dogs were divided into three groups. In the infected-I group (5 dogs), the intimal lesions of the pulmonary arteries were slight, and clinical and laboratory findings showed changes similar to those of the uninfected group. In the infected-II group (4 dogs), the pulmonary arterial lesions were severe and the mean PAP was higher (25.7 mmHg) than in the uninfected group before worm insertion. An increase in PAP (34.1 mmHg) and worsening of clinical and laboratory findings were noticed till the 4th week. Thromboemboli adhered extensively to the vessel walls. Two dogs in the infected-III group died of severe dyspnea on the 9th and 10th day, and the mean PAP rose remarkably at the 1st week (from 19.4 to 28.2 mmHg). Severe pulmonary parenchymal lesions with edema or perforation were observed. From the above results, it was clarified that effects of dead worms on PAP and clinical signs depended on the severity of pulmonary arterial lesions before worm insertion.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Relationship Between the Middle Genicular Artery and the Posterior Structures of the Knee

    PubMed Central

    de Carvalho, Rogério Teixeira; Ramos, Leonardo Addêo; Novaretti, João Victor; Ribeiro, Leandro Masini; Szeles, Paulo Roberto de Queiroz; Ingham, Sheila Jean McNeill; Abdalla, Rene Jorge

    2016-01-01

    Background: The middle genicular artery (MGA) is responsible for the blood supply to the cruciate ligaments and synovial tissue. Traumatic sports injuries and surgical procedures (open and arthroscopic) can cause vascular damage. Little attention has been devoted to establish safe parameters for the MGA. Purpose: To investigate the anatomy of the MGA and its relation to the posterior structures of the knees, mainly the posterior capsule and femoral condyles, and to establish safe parameters to avoid harming the MGA. Study Design: Descriptive laboratory study. Methods: Dissection of the MGA was performed in 16 fresh, unpaired adult human cadaveric knees with no macroscopic degenerative or traumatic changes and no previous surgeries. The specimens were meticulously evaluated with emphasis on preservation of the MGA. The distances from the MGA to the medial and lateral femoral condyles were measured. The Mann-Whitney test was used for statistical analysis. Results: In all specimens, the MGA emerged from the anterior aspect of the popliteal artery, distal to the superior genicular arteries, and had a short distal trajectory toward the posterior capsule where it entered proximal to the oblique popliteal ligament. The artery lay in the midportion between the condyles. The distance between the posterior aspect of the tibia and the point of entry of the MGA into the posterior joint capsule was 23.8 ± 7.3 mm (range, 14.72-35.68 mm). There was no correlation between an individual’s height and the distance of the entrance point of the MGA into the posterior joint capsule to the posterior superior corner of the tibia. Conclusion: The middle genicular artery lies in the midportion between the medial and lateral femoral condyles. Clinical Relevance: This knowledge is important for the preservation of the blood supply during posterior knee surgical procedures and to settle a secure distance between the posterior aspect of the tibia and the MGA input. This could decrease and

  4. Relationship between pre-extubation positive endexpiratory pressure and oxygenation after coronary artery bypass grafting

    PubMed Central

    Lima, Reijane Oliveira; Borges, Daniel Lago; Costa, Marina de Albuquerque Gonçalves; Baldez, Thiago Eduardo Pereira; Silva, Mayara Gabrielle Barbosa e; Sousa, Felipe André Silva; Soares, Milena de Oliveira; Pinto, Jivago Gentil Moreira

    2015-01-01

    Introduction After removal of endotracheal tube and artificial ventilation, ventilatory support should be continued, offering oxygen supply to ensure an arterial oxygen saturation close to physiological. Objective The aim of this study was to investigate the effects of positive-end expiratory pressure before extubation on the oxygenation indices of patients undergoing coronary artery bypass grafting. Methods A randomized clinical trial with seventy-eight patients undergoing coronary artery bypass grafting divided into three groups and ventilated with different positive-end expiratory pressure levels prior to extubation: Group A, 5 cmH2O (n=32); Group B, 8 cmH2O (n=26); and Group C, 10 cmH2O (n=20). Oxygenation index data were obtained from arterial blood gas samples collected at 1, 3, and 6 h after extubation. Patients with chronic pulmonary disease and those who underwent off-pump, emergency, or combined surgeries were excluded. For statistical analysis, we used Shapiro-Wilk, G, Kruskal-Wallis, and analysis of variance tests and set the level of significance at P<0.05. Results Groups were homogenous with regard to demographic, clinical, and surgical variables. There were no statistically significant differences between groups in the first 6 h after extubation with regard to oxygenation indices and oxygen therapy utilization. Conclusion In this sample of patients undergoing coronary artery bypass grafting, the use of different positive-end expiratory pressure levels before extubation did not affect gas exchange or oxygen therapy utilization in the first 6 h after endotracheal tube removal. PMID:27163418

  5. The relationship between various measures of obesity and arterial stiffness in morbidly obese patients

    PubMed Central

    2011-01-01

    Background Obesity is associated with increased risk of cardiovascular disease. Arterial stiffness assessed by carotid femoral pulse wave velocity (PWV) is an independent predictor of cardiovascular morbidity and mortality. We aimed to investigate how various measures of body composition affect arterial stiffness. Methods This is an analysis of cross-sectional baseline data from a controlled clinical trial addressing changes in arterial stiffness after either surgery or lifestyle intervention in a population of morbidly obese patients. High-fidelity applanation tonometry (Millar®, Sphygmocor®) was used to measure pulse wave velocity (PWV). Carotid femoral PWV is a direct measure of arterial stiffness and is considered to be the gold standard method. The Inbody 720 Body Composition Analyzer was used for bioelectrical impedance analysis (BIA). Spearman's correlation, independent samples t-test, chi-square tests, Fisher's exact test and multiple linear regression analyses were used as statistical methods. Results A total of 133 patients (79 women), with a mean (SD) age of 43 (11) years were included in the study. Men had a significantly higher prevalence of obesity related comorbidities and significantly higher PWV, 9.1 (2.0) m/s vs. 8.1 (1.8) m/s, p = 0.003, than women. In the female group, PWV was positively correlated with WC, WHtR, BMI and visceral fat area. In the male group, PWV was negatively correlated with BMI. Multiple linear regression analysis showed that increasing BMI, WC, WHtR, visceral fat area and fat mass were independently associated with higher PWV in women, but not in men, after adjustment for age, hypertension and type 2 diabetes. Conclusion Most measures of general and abdominal obesity were predictors of arterial stiffness in female morbidly obese patients. Trial registration ClinicalTrials.gov Identifier NCT00626964 PMID:21284837

  6. The relationship between distribution of body fat mass and carotid artery intima-media thickness in Korean older adults.

    PubMed

    Park, Jin-Kee; Park, Hyuntae; Kim, Kwi-Baek

    2015-10-01

    [Purpose] The aim of this study was to examine the relationships between the amount and distribution of body fat and the carotid intima-media thickness to explore whether coronary artery disease risk may be mediated through effects on the amount of fat mass in older adults. [Subjects and Methods] A total of 200 elderly females was participated. The percentage of body fat mass was measured by the bioelectrical impedance analysis method, and the carotid intima-media thickness was measured by B-mode ultrasound. Analysis of covariance was performed to assess independent associations between the four categories of percentage of body fat mass and the carotid intima-media thickness after multivariate adjustment. Logistic regression analyses were utilized to calculate odds ratios and 95% confidence intervals for examining independent associations between percentage of body fat mass and the estimated risk of coronary artery disease. [Results] Analysis of covariance showed that the carotid intima-media thickness was significantly thick in both obesity and overweight groups. When multivariate-adjusted OR for the estimated risk of coronary artery disease, the odds ratios for the obesity and overweight groups were 3.0 (95% confidence interval, 1.1 to 8.7) and 2.5 (95% confidence interval, 1.0 to 6.1), respectively. [Conclusion] This study demonstrates that elderly females with a high body fat mass are more likely to have the estimated risk of CAD than who fit body fat mass in elderly female.

  7. The relationship between distribution of body fat mass and carotid artery intima-media thickness in Korean older adults

    PubMed Central

    Park, Jin-Kee; Park, Hyuntae; Kim, Kwi-Baek

    2015-01-01

    [Purpose] The aim of this study was to examine the relationships between the amount and distribution of body fat and the carotid intima-media thickness to explore whether coronary artery disease risk may be mediated through effects on the amount of fat mass in older adults. [Subjects and Methods] A total of 200 elderly females was participated. The percentage of body fat mass was measured by the bioelectrical impedance analysis method, and the carotid intima-media thickness was measured by B-mode ultrasound. Analysis of covariance was performed to assess independent associations between the four categories of percentage of body fat mass and the carotid intima-media thickness after multivariate adjustment. Logistic regression analyses were utilized to calculate odds ratios and 95% confidence intervals for examining independent associations between percentage of body fat mass and the estimated risk of coronary artery disease. [Results] Analysis of covariance showed that the carotid intima-media thickness was significantly thick in both obesity and overweight groups. When multivariate-adjusted OR for the estimated risk of coronary artery disease, the odds ratios for the obesity and overweight groups were 3.0 (95% confidence interval, 1.1 to 8.7) and 2.5 (95% confidence interval, 1.0 to 6.1), respectively. [Conclusion] This study demonstrates that elderly females with a high body fat mass are more likely to have the estimated risk of CAD than who fit body fat mass in elderly female. PMID:26633917

  8. Pressure-volume equation of state for pyrope-almandine solid solutions

    NASA Astrophysics Data System (ADS)

    Nestola, Fabrizio; Milani, Sula; Angel, Ross J.; Pasqual, Daria; Geiger, Charles A.

    2013-04-01

    Garnet is a key phase of Earth's upper mantle and one of the most abundant solid inclusions in diamonds. The pyrope component (Mg3Al2Si3O12, Py) of garnet found in diamonds of peridotitic and eclogitic origin can be as high as about 79 and 43%, respectively and the almandine component (Fe3Al2Si3O12, Al) is about 11 and 33%, respectively. Thus such garnets are largely Py-Al-rich solid solutions (Stachel and Harris, 2008). To determine the depth of formation of diamond-inclusion pairs, precise and accurate thermoelastic parameters for both the diamond and the solid inclusion phase are necessary (e.g. Izraeli et al., 1999; Howell et al., 2010; Nestola et al., 2011; Howell et al., 2012). We are presently investigating the pressure-volume equation of state for a series of synthetic garnets along the binary pyrope-almandine by X-ray single-crystal diffraction using a diamond anvil cell up to a maximum of 8 GPa pressure. We have completed measurements on two crystals of composition Fe3Al2Si3O12 and Fe1.20Mg1.80Al2Si3O12. The equation of state coefficients obtained by fitting a third-order Birch-Murnaghan to the pressure-volume data show that an increase in the pyrope component in garnet causes a slight decrease of the isothermal bulk modulus, KT0, by about 3%, whereas the first pressure derivative term does not vary. Applying our results to obtain the pressure of formation of a natural diamond-garnet pair, and assuming a garnet composition close to Fe1.20Mg1.80Al2Si3O12, we obtain a pressure of encapsulation (or formation if garnet and diamond are syngenetic) of garnet in diamond between 6.5 and 7.0 GPa. References Howell, D., Wood, I.G., Dobson, D.P., Jones, A.P., Nasdala, L., Harris, J.W. (2010) Contrib. Mineral. Petrol., 160, 705-717. Howell, D., Wood, I.G., Nestola, F., Nimis, P., Nasdala, L. (2012) Eur. J. Mineral., ,. Izraeli, E.S., Harris, J.W., Navon, O. (1999) Earth Planet Sci. Lett., 173, 351-360. Nestola, F., Nimis, P., Ziberna, L., Longo, M., Marzoli, A

  9. Relationship between dyslipidemia, C-reactive protein and serological evidence of Chlamydia pneumoniae in Turkish patients with coronary artery diseases.

    PubMed

    Turkoglu, C; Sonmez, E; Aydinli, A

    2004-07-01

    Relationship between dyslipidemia, C-Reactive Protein (CRP) and serological evidence of Chlamydia pneumoniae was investigated in a Turkish population with coronary artery disease. This prospective, randomized, blinded study was carried out in Florence Nightingale Hospital which is affiliated to Kadir Has University, Medical Faculty. Thirty-two patients with acute coronary artery diseases (ACAD), 32 patients with chronic coronary artery diseases (CCAD) and 26 healthy controls (HC) were included in the study. We detected serum concentrations of C. pneumoniae IgG, IgA and IgM by ELISA method. We measured total cholesterol, trigliseride, LDL and HDL- cholesterol levels to determine dyslipidemia which was defined as total cholesterol >200 mg/dL, trigliserid > 150 mg/dL, LDL >130 mg/dL, HDL <45 mg/dL. CRP levels were also measured. Seropositivity to C. pneumoniae IgG was 84.3%, 100% and 65.3%; seropositivity to IgA was 9.3%, 6.2%, and 3.8%; and seropositivity to IgM was 12.5%, 15.3%, and 15.4% in patients with ACAD, CCAD and HC, respectively. Dyslipidemia was found as 93.7%, 78. 1% and 0% of patients with ACAD, CCAD and HC, respectively. CRP level was high in all patients (ACAD, CCAD) but not in healthy controls. As a conclusion, we found a significant association between seropositivity to C. pneumoniae IgG and dyslipidemia and CRP levels in ACAD and CCAD patients (p<0.05). C. pneumoniae IgG antibodies should be evaluated together with serum lipids and CRP levels in patients with ACAD and CCAD in Turkish population. This may help clinicians in treatment of C. pneumoniae infection and decrease the risk of coronary artery diseases.

  10. Decreased creatine kinase is linked to diastolic dysfunction in rats with right heart failure induced by pulmonary artery hypertension.

    PubMed

    Fowler, Ewan D; Benoist, David; Drinkhill, Mark J; Stones, Rachel; Helmes, Michiel; Wüst, Rob C I; Stienen, Ger J M; Steele, Derek S; White, Ed

    2015-09-01

    Our objective was to investigate the role of creatine kinase in the contractile dysfunction of right ventricular failure caused by pulmonary artery hypertension. Pulmonary artery hypertension and right ventricular failure were induced in rats by monocrotaline and compared to saline-injected control animals. In vivo right ventricular diastolic pressure-volume relationships were measured in anesthetized animals; diastolic force-length relationships in single enzymatically dissociated myocytes and myocardial creatine kinase levels by Western blot. We observed diastolic dysfunction in right ventricular failure indicated by significantly steeper diastolic pressure-volume relationships in vivo and diastolic force-length relationships in single myocytes. There was a significant reduction in creatine kinase protein expression in failing right ventricle. Dysfunction also manifested as a shorter diastolic sarcomere length in failing myocytes. This was associated with a Ca(2+)-independent mechanism that was sensitive to cross-bridge cycling inhibition. In saponin-skinned failing myocytes, addition of exogenous creatine kinase significantly lengthened sarcomeres, while in intact healthy myocytes, inhibition of creatine kinase significantly shortened sarcomeres. Creatine kinase inhibition also changed the relatively flat contraction amplitude-stimulation frequency relationship of healthy myocytes into a steeply negative, failing phenotype. Decreased creatine kinase expression leads to diastolic dysfunction. We propose that this is via local reduction in ATP:ADP ratio and thus to Ca(2+)-independent force production and diastolic sarcomere shortening. Creatine kinase inhibition also mimics a definitive characteristic of heart failure, the inability to respond to increased demand. Novel therapies for pulmonary artery hypertension are needed. Our data suggest that cardiac energetics would be a potential ventricular therapeutic target. Copyright © 2015. Published by Elsevier Ltd.

  11. Pipeline Embolization Device for small paraophthalmic artery aneurysms with an emphasis on the anatomical relationship of ophthalmic artery origin and aneurysm.

    PubMed

    Griessenauer, Christoph J; Ogilvy, Christopher S; Foreman, Paul M; Chua, Michelle H; Harrigan, Mark R; Stapleton, Christopher J; Patel, Aman B; He, Lucy; Fusco, Matthew R; Mocco, J; Winkler, Peter A; Patel, Apar S; Thomas, Ajith J

    2016-12-01

    OBJECTIVE Contemporary treatment for paraophthalmic artery aneurysms includes flow diversion utilizing the Pipeline Embolization Device (PED). Little is known, however, about the potential implications of the anatomical relationship of the ophthalmic artery (OA) origin and aneurysm, especially in smaller aneurysms. METHODS Four major academic institutions in the United States provided data on small paraophthalmic aneurysms (≤ 7 mm) that were treated with PED between 2009 and 2015. The anatomical relationship of OA origin and aneurysm, radiographic outcomes of aneurysm occlusion, and patency of the OA were assessed using digital subtraction angiography. OA origin was classified as follows: Type 1, OA separate from the aneurysm; Type 2, OA from the aneurysm neck; and Type 3, OA from the aneurysm dome. Clinical outcome was assessed using the modified Rankin Scale, and visual deficits were categorized as transient or permanent. RESULTS The cumulative number of small paraophthalmic aneurysms treated with PED between 2009 and 2015 at the 4 participating institutions was 69 in 52 patients (54.1 ± 13.7 years of age) with a male-to-female ratio of 1:12. The distribution of OA origin was 72.5% for Type 1, 17.4% for Type 2, and 10.1% for Type 3. Radiographic outcome at the last follow-up (median 11.5 months) was available for 54 aneurysms (78.3%) with complete, near-complete, and incomplete occlusion rates of 81.5%, 5.6%, and 12.9%, respectively. Two aneurysms (3%) resulted in transient visual deficits, and no patient experienced a permanent visual deficit. At the last follow-up, the OA was patent in 96.8% of treated aneurysms. Type 3 OA origin was associated with a lower rate of complete aneurysm occlusion (p = 0.0297), demonstrating a trend toward visual deficits (p = 0.0797) and a lower rate of OA patency (p = 0.0783). CONCLUSIONS Pipeline embolization treatment of small paraophthalmic aneurysms is safe and effective. An aneurysm where the OA arises from the aneurysm

  12. Pressure-Volume-Temperature (PVT) Gauging of an Isothermal Cryogenic Propellant Tank Pressurized with Gaseous Helium

    NASA Technical Reports Server (NTRS)

    VanDresar, Neil T.; Zimmerli, Gregory A.

    2014-01-01

    Results are presented for pressure-volume-temperature (PVT) gauging of a liquid oxygen/liquid nitrogen tank pressurized with gaseous helium that was supplied by a high-pressure cryogenic tank simulating a cold helium supply bottle on a spacecraft. The fluid inside the test tank was kept isothermal by frequent operation of a liquid circulation pump and spray system, and the propellant tank was suspended from load cells to obtain a high-accuracy reference standard for the gauging measurements. Liquid quantity gauging errors of less than 2 percent of the tank volume were obtained when quasi-steady-state conditions existed in the propellant and helium supply tanks. Accurate gauging required careful attention to, and corrections for, second-order effects of helium solubility in the liquid propellant plus differences in the propellant/helium composition and temperature in the various plumbing lines attached to the tanks. On the basis of results from a helium solubility test, a model was developed to predict the amount of helium dissolved in the liquid as a function of cumulative pump operation time. Use of this model allowed correction of the basic PVT gauging calculations and attainment of the reported gauging accuracy. This helium solubility model is system specific, but it may be adaptable to other hardware systems.

  13. Improved pressure-volume-temperature method for estimation of cryogenic liquid volume

    NASA Astrophysics Data System (ADS)

    Seo, Mansu; Jeong, Sangkwon; Jung, Young-suk; Kim, Jakyung; Park, Hana

    2012-04-01

    One of the most important issues in a liquid propellant rocket is to measure the amount of remaining liquid propellant under low gravity environment during space mission. This paper presents the results of experiment and analysis of a pressure-volume-temperature (PVT) method which is a gauging method for low gravity environment. The experiment is conducted using 7.4 l tank for liquid nitrogen with various liquid-fill levels. To maximize the accuracy of a PVT method with minimum hardware, the technique of a helium injection with low mass flow rate is applied to maintain stable temperature profile in the ullage volume. The PVT analysis considering both pressurant and cryogen as a binary mixture is suggested. At high liquid-fill levels of 72-80%, the accuracy from the conventional PVT analysis is within 4.6%. At low fill levels of 27-30%, the gauging error is within 3.4% by mixture analysis of a PVT method with specific low mass flow rate of a helium injection. It is concluded that the proper mass flow rate of a helium injection and PVT analyses are crucial to enhance the accuracy of the PVT method with regard to various liquid-fill levels.

  14. Intracranial pressure, its components and cerebrospinal fluid pressure-volume compensation.

    PubMed

    Kasprowicz, M; Lalou, D A; Czosnyka, M; Garnett, M; Czosnyka, Z

    2016-09-01

    Clinical measurement of intracranial pressure (ICP) is often performed to aid diagnosis of hydrocephalus. This review discusses analysis of ICP and its components' for the investigation of cerebrospinal fluid (CSF) dynamics. The role of pulse, slow and respiratory waveforms of ICP in diagnosis, prognostication and management of hydrocephalus is presented. Two methods related to ICP measurement are listed: an overnight monitoring of ICP and a constant-rate infusion study. Due to the dynamic nature of ICP, a 'snapshot' manometric measurement of ICP is of limited use as it might lead to unreliable results. Therefore, monitoring of ICP over longer time combined with analysis of its waveforms provides more detailed information on the state of pressure-volume compensation. The infusion study implements ICP signal processing and CSF circulation model analysis in order to assess the cerebrospinal dynamics variables, such as CSF outflow resistance, compliance of CSF space, pressure amplitude, reference pressure, and CSF formation. These parameters act as an aid tool in diagnosis and prognostication of hydrocephalus and can be helpful in the assessment of a shunt malfunction. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. The pressure-volume curve is greatly modified by recruitment. A mathematical model of ARDS lungs.

    PubMed

    Hickling, K G

    1998-07-01

    A mathematical model of the ARDS lung, with simulated gravitational superimposed pressure, evaluated the effect of varying alveolar threshold opening pressures (TOP), PEEP and peak inspiratory pressure (PIP) on the static pressure-volume (PV) curve. The lower inflection point (Pflex) was affected by SP and TOP, and did not accurately indicate PEEP required to prevent end-expiratory collapse. Reinflation of collapsed lung units (recruitment) continued on the linear portion of the PV curve, which had a slope at any volume greater than the total compliance of aerated alveoli. As recruitment diminished, the reduced PV slope could produce an upper Pflex at 20 to 30 cm H2O pressure. An upper Pflex caused by alveolar overdistension could be modified or eliminated by recruitment with high TOP. With constant PIP as PEEP increased, and TOP range of 5 to 60 cm H2O, PEEP to prevent end-expiratory collapse was indicated by minimum PV slope above 20 cm H2O, minimum hysteresis, and maximum volume at a pressure of 20 cm H2O. With constant inflation volume as PEEP increased, the effect on PV slope was unpredictable. Although increased PV slope indicated recruitment, maximum PV slope usually underestimated PEEP required to prevent end-expiratory collapse. Therefore, with this model the PV curve did not reliably predict optimal ventilator settings.

  16. Cook-off violence mapping and pressure-volume relations with a scaled deflagration cylinder test

    NASA Astrophysics Data System (ADS)

    Pierce, Timothy; Hooks, Daniel

    2009-06-01

    There have been significant advances in the scientific understanding of cook-off in explosives, which have led to a generalized mechanistic understanding of the processes involved for certain explosives. Several deflagration cylinder tests (DFCT) tests were recently fielded that alluded to regimes of outcomes depending on the history and state of the system. Importantly, a few of these tests also exhibited steady-wave combustion that enabled, using the method of G. I. Taylor, extraction of a pressure-volume relation for the conditions of the test. Such a relation, dubbed a ``pseudo-equation of state'' (pEOS), allows one to inform models to simulate the possible outcomes of violent reaction using hydrodynamic codes. Thus, this test was extremely valuable in that it demonstrated the possibility of both mapping outcomes based on system variables and external conditions and provides data to inform predictive models. We describe a scaled version of the DFCT. It delivers pEOS data when steady combustion is observed, and is inexpensive enough to map outcomes by fielding many tests.

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

    PubMed

    Green, Daniel J; Eijsvogels, Thijs; Bouts, Yvette M; Maiorana, Andrew J; Naylor, Louise H; Scholten, Ralph R; Spaanderman, Marc E A; Pugh, Christopher J A; Sprung, Victoria S; Schreuder, Tim; Jones, Helen; Cable, Tim; Hopman, Maria T E; Thijssen, Dick H J

    2014-08-15

    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 factors to exercise-induced changes in artery function. We pooled data from our laboratories involving 182 subjects who underwent supervised, large-muscle group, endurance-type exercise training interventions with pre-/posttraining measures of flow-mediated dilation (FMD%) to assess artery function. All studies adopted an identical FMD protocol (5-min ischemia, distal cuff inflation), contemporary echo-Doppler methodology, and observer-independent automated analysis. Linear regression analysis was used to identify factors contributing to changes in FMD%. We found that cardiopulmonary fitness improved, and weight, body mass index (BMI), cholesterol, and mean arterial pressure (MAP) decreased after training, while FMD% increased in 76% of subjects (P < 0.001). Training-induced increase in FMD% was predicted by lower body weight (β = -0.212), lower baseline FMD% (β = -0.469), lower training frequency (β = -0.256), and longer training duration (β = 0.367) (combined: P < 0.001, r = 0.63). With the exception of a modest correlation with total cholesterol (r = -0.243, P < 0.01), changes in traditional cardiovascular risk factors were not significantly related to changes in FMD% (P > 0.05). In conclusion, we found that, while some subjects do not demonstrate increases following exercise training, improvement in FMD% is present in those with lower pretraining body weight and endothelial function. Moreover, exercise training-induced change in FMD% did not correlate with changes in traditional cardiovascular risk factors, indicating that some cardioprotective effects of exercise training are independent of improvement in risk factors.

  18. The Relationship between P & QT Dispersions and Presence & Severity of Stable Coronary Artery Disease

    PubMed Central

    Yıldırım, Erkan; Ipek, Emrah; Cengiz, Mahir; Aslan, Kursat; Poyraz, Esra; Demirelli, Selami; Bayantemur, Murat; Ermis, Emrah; Ciftci, Cavlan

    2016-01-01

    Background and Objectives The study aimed to evaluate the correlation between electrocardiographic (ECG) parameters and presence and extent of coronary artery disease (CAD) to indicate the usefulness of these parameters as predictors of severity in patients with stable CAD. Subjects and Methods Two hundred fifty patients, without a history of any cardiovascular event were included in the study. The ECG parameters were measured manually by a cardiologist before coronary angiography. The patients were allocated into five groups: those with normal coronary arteries (Group 1), non-critical coronary lesions (Group 2), one, two and three vessel disease (Group 3, Group 4 and Group 5, respectively. Results Group 1 had the lowest P wave dispersion (PWD) and P wave (Pmax), QT interval (QTmax), QT dispersion (QTd), corrected QT dispersion (QTcd) and QT dispersion ratio (QTdR), while the patients in group 5 had the highest values of these parameters. Gensini score and QTmax, QTd, QTcmax, QTcd, QTdR, Pmax, and PWD were positively correlated. QTdR was the best ECG parameter to differentiate group 1 and 2 from groups with significant stenosis (groups 3, 4, and 5) (area under curve [AUC] 0.846). QTdR was the best ECG parameter to detect coronary arterial narrowing lesser than 50% and greater than 50%, respectively (AUC 0.858). Conclusion Presence and severity of CAD can be determined by using ECG in patients with stable CAD and normal left ventricular function. PMID:27482261

  19. The relationship between the metabolic syndrome and arterial wall thickness: A mosaic still to be interpreted.

    PubMed

    Scuteri, Angelo; Franco, Oscar H; Majiid, AlGhatrif; Jolita, Badariene; Sergey, Boytsov; Cheng, Hao-Min; Chen, Chen-Huan; Choi, Seong-Woo; Francesco, Cucca; De Buyzere, Marc L; Alessandro, Delitala; Marcus, Dörr; Gunnar, Engstrom; Albert, Hofman; Seul-Ki, Jeong; Kweon, Sun-Seog; Michel, Langlois; Lee, Young-Hoon; Mattace Raso, Francesco; Olle, Melander; Morrell, Cristopher H; Park, Kyeong-Soo; Rietzschel, Ernst R; Kristina, Ryliskiene; Ryliskyte, Ligita; Ulf, Schminke; David, Schlessinger; Shin, Min-Ho; Irina, Strazhesko; Shih-Hsien, Sung; Olga, Tkacheva; Völzke, Henry; Lakatta, Edward G; Nilsson, Peter

    2016-12-01

    We aimed to identify clusters of metabolic syndrome (MetS) components, risky for extremely high intima-media thickness. We studied 41,513 volunteers (men and women) from eleven cohorts worldwide, participating in the MARE (Metabolic syndrome and Artery REsearch) Consortium. Specific clusters of MetS components - high triglycerides-high blood pressure-abdominal obesity (TBW), low HDL cholesterol-high blood pressure-abdominal obesity (HBW), high glucose-high blood pressure-abdominal obesity (GBW) - were accompanied by a 50-90% significantly greater likelihood of presenting extremely high intima-media thickness (via ultrasound of carotid artery, CCA IMT), after controlling for age, sex, smoking, non-HDL cholesterol, and presence of diabetes mellitus. This likelihood is comparable to the effect of being 7-8 years older or of being a cigarette smoker or of having non-HDL cholesterol 50 mg/dl higher. The consistent association of specific clusters of MetS components with extremely thick (older) large artery cross-culturally suggests that identification of those clusters in clinical practice will facilitate a personalized health care and a better - i.e. more healthy and cost-effective - prevention of major cardiovascular (CV) events. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease.

    PubMed

    Hartkamp, Nolan S; Petersen, Esben T; Chappell, Michael A; Okell, Thomas W; Uyttenboogaart, Maarten; Zeebregts, Clark J; Bokkers, Reinoud Ph

    2017-01-01

    Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.

  1. Relationships between myocardial macrominerals and trace elements and luminal narrowing of coronary arteries in Finnish children.

    PubMed

    Alfthan, G; Pesonen, E; Neuvonen, P J; Hirvonen, J; Karkola, K; Laaksonen, H; Räsänen, L; Akerblom, H K

    1992-03-01

    In addition to the traditional risk factors for cardiovascular diseases it has been hypothesized that a suboptimal intake of macrominerals and trace elements plays a role in the etiology of such diseases. We studied the possible correlation between preatherosclerotic changes in the coronary arteries and the myocardial concentration of K, Ca, Mg, Fe, Zn, Cu and Se in an autopsy series of children who had died mainly from accidental causes (n = 58). The concentrations of myocardial elements were comparable to values published elsewhere except for a slightly higher Cu concentration. The myocardial Se concentration indicated an adequate Se status. Narrowing of the coronary artery lumen was not correlated with myocardial element concentration except in the case of Se, for which a positive correlation was found (r = 0.23, p less than 0.04). Myocardial K was positively correlated with myocardial Mg (r = 0.65, p less than 0.001) and inversely correlated with Ca (r = -0.50, p less than 0.001). The intake of saturated vs. unsaturated fats was associated with myocardial Cu and Ca concentrations. Our results suggest that myocardial macrominerals and trace elements do not play a role in juvenile preatherosclerotic changes of the arteries.

  2. Prevalence of coronary artery ectasia in older adults and the relationship with epicardial fat volume by cardiac computed tomography angiography

    PubMed Central

    Yang, Jun-Jie; Yang, Xia; Chen, Zhi-Ye; Wang, Qi; He, Bai; Du, Luo-Shan; Chen, Yun-Dai

    2013-01-01

    Objective Coronary artery ectasia (CAE) refers to abnormal dilation of coronary artery segments to 1.5 times of adjacent normal ones. Epicardial fat is associated with cardiovascular risk factors. The relationship between CAE and epicardial fat has not yet been investigated. This study aimed to assess the relationship between CAE and epicardial fat volume (EFV) in older people by dual-source computed tomography coronary angiography (CTCA). Methods We prospectively enrolled 1400 older adults who were scheduled for dual-source CTCA. Under reconstruction protocols, patients with abnormal segments 1.5 times larger than the adjacent segments were accepted as CAE. EFV was measured by semi-automated software. Traditional risk factors in CAE patients, as well as the extent of EFV, were analyzed and compared to non-CAE group. Results A total of 885 male and 515 female older patients were enrolled. CAE was identified by univariable analysis in 131 patients and significantly correlated to hypertension, smoking, hyperlipidemia, prior percutaneous coronary intervention and ascending aorta aneurysm. EFV was shown to be significantly higher in CAE patients than patients without ectasia. In multivariable analyses, EFV (P = 0.018), hypertension (P < 0.001) and hyperlipidemia (P < 0.001) were significantly correlated to CAE. There was a significant negative correlation between EFV and Markis classification. Conclusions CAE can be reliably recognized by dual-source CTCA. Epicardial fat might play a role in etiopathogenesis and progression of CAE, providing a new target for treating ectasia. PMID:23610568

  3. Relationship between cardio-ankle vascular index (CAVI) and coronary artery calcification (CAC) in patients with type 2 diabetes mellitus.

    PubMed

    Mineoka, Yusuke; Fukui, Michiaki; Tanaka, Muhei; Tomiyasu, Ki-ichiro; Akabame, Satoshi; Nakano, Koji; Yamazaki, Masahiro; Hasegawa, Goji; Oda, Yohei; Nakamura, Naoto

    2012-03-01

    Early detection of atherosclerosis is important for patients with type 2 diabetes mellitus because cardiovascular disease (CVD) is a main cause of death in these people. In this study, we investigated the relationship between an arterial stiffness parameter called cardio-ankle vascular index (CAVI) and coronary artery calcification (CAC). We performed a cross-sectional study in 371 type 2 diabetic patients with clinical suspicion of coronary heart disease (CHD). We evaluated the relationships between CAVI and CAC score determined by multislice computed tomography as well as major cardiovascular risk factors, including age, body mass index, hemoglobinA1c and the Framingham CHD risk score. CAVI was correlated with age (r = 0.301, p < 0.0001), uric acid (r = 0.236, p < 0.0001), estimated glomerular filtration rate (r = -0.145, p = 0.0166), CHD risk score (r = 0.327, p < 0.0001) and log (CAC + 1) (r = 0.303, p < 0.0001). The area under the receiver operating characteristic curve for CAVI was higher than that of CHD risk score in predicting CAC >0, CAC >100, CAC >400, or CAC >1000. CAVI is positively correlated with CAC, and is considered to be a useful method to detect CAC.

  4. Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.

    PubMed

    Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

    2013-01-01

    Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging.

  5. The relationship of pulmonary vascular resistance and compliance to pulmonary artery wedge pressure during submaximal exercise in healthy older adults

    PubMed Central

    Wright, Stephen P.; Granton, John T.; Esfandiari, Sam; Goodman, Jack M.

    2016-01-01

    Key points A consistent inverse hyperbolic relationship has been observed between pulmonary vascular resistance and compliance, although changes in pulmonary artery wedge pressure (PAWP) may modify this relationship.This relationship predicts that pulmonary artery systolic, diastolic and mean pressure maintain a consistent relationship relative to the PAWP.We show that, in healthy exercising human adults, both pulmonary vascular resistance and compliance decrease in relation to exercise‐associated increases in PAWP.Pulmonary artery systolic, diastolic and mean pressures maintain a consistent relationship with one another, increasing linearly with increasing PAWP.Increases in PAWP in the setting of exercise are directly related to a decrease in pulmonary vascular compliance, despite small decreases in pulmonary vascular resistance, thereby increasing the pulsatile afterload to the right ventricle. Abstract The resistive and pulsatile components of right ventricular afterload (pulmonary vascular resistance, Rp; compliance, Cp) are related by an inverse hyperbolic function, expressed as their product known as RpCp‐time. The RpCp‐time exhibits a narrow range, although it may be altered by the pulmonary artery wedge pressure (PAWP). Identifying the determinants of RpCp‐time should improve our understanding of the physiological behaviour of pulmonary arterial systolic (PASP), diastolic (PADP) and mean (mPAP) pressures in response to perturbations. We examined the effect of exercise in 28 healthy non‐athletic adults (55 ± 6 years) who underwent right heart catheterization to assess haemodynamics and calculate Rp and Cp. Measurements were made at rest and during two consecutive 8–10 min stages of cycle ergometry, at targeted heart‐rates of 100 beats min–1 (Light) and 120 beats min–1 (Moderate). Cardiac output increased progressively during exercise. PASP, PADP, mPAP and PAWP increased for Light exercise, without any further rise for Moderate

  6. The relationship of pulmonary vascular resistance and compliance to pulmonary artery wedge pressure during submaximal exercise in healthy older adults.

    PubMed

    Wright, Stephen P; Granton, John T; Esfandiari, Sam; Goodman, Jack M; Mak, Susanna

    2016-06-15

    A consistent inverse hyperbolic relationship has been observed between pulmonary vascular resistance and compliance, although changes in pulmonary artery wedge pressure (PAWP) may modify this relationship. This relationship predicts that pulmonary artery systolic, diastolic and mean pressure maintain a consistent relationship relative to the PAWP. We show that, in healthy exercising human adults, both pulmonary vascular resistance and compliance decrease in relation to exercise-associated increases in PAWP. Pulmonary artery systolic, diastolic and mean pressures maintain a consistent relationship with one another, increasing linearly with increasing PAWP. Increases in PAWP in the setting of exercise are directly related to a decrease in pulmonary vascular compliance, despite small decreases in pulmonary vascular resistance, thereby increasing the pulsatile afterload to the right ventricle. The resistive and pulsatile components of right ventricular afterload (pulmonary vascular resistance, Rp; compliance, Cp) are related by an inverse hyperbolic function, expressed as their product known as RpCp-time. The RpCp-time exhibits a narrow range, although it may be altered by the pulmonary artery wedge pressure (PAWP). Identifying the determinants of RpCp-time should improve our understanding of the physiological behaviour of pulmonary arterial systolic (PASP), diastolic (PADP) and mean (mPAP) pressures in response to perturbations. We examined the effect of exercise in 28 healthy non-athletic adults (55 ± 6 years) who underwent right heart catheterization to assess haemodynamics and calculate Rp and Cp. Measurements were made at rest and during two consecutive 8-10 min stages of cycle ergometry, at targeted heart-rates of 100 beats min(-1) (Light) and 120 beats min(-1) (Moderate). Cardiac output increased progressively during exercise. PASP, PADP, mPAP and PAWP increased for Light exercise, without any further rise for Moderate exercise. RpCp-time decreased for

  7. Relationship between antiphospholipid antibodies and progression of lower extremity arterial occlusive disease after lower extremity bypass operations.

    PubMed

    Lam, E Y; Taylor, L M; Landry, G J; Porter, J M; Moneta, G L

    2001-05-01

    Antiphospholipid antibodies (APLs), which consist of anticardiolipin antibodies (ACLs) or lupus anticoagulant (LA), are associated with venous thrombosis, stroke, and cardiac events. Although they are present in many patients with lower extremity atherosclerotic occlusive disease (LEAOD), the relationship between APL and the progression of LEAOD has not been reported. A comparison of progression of LEAOD as determined with direct imaging studies in patients with and without APL forms the basis for this report. APL+ patients (immunoglobulin M [IgM] or IgA or IgG ACL > 3 SD units above control mean or positive LA) who underwent lower extremity bypass grafting between January 1990 and June 1999 (n = 79) were compared with an APL control group (n = 68). Members of the study and control groups were similar with respect to age, procedure, sex, length of follow-up, and multiple atherosclerosis risk factors. Progression of LEAOD was determined by comparing preoperative arteriograms with postoperative imaging studies (arteriograms or duplex scanning). External iliac, common femoral, superficial femoral and popliteal arteries were graded as < 50% stenosis, > or = 50% stenosis, or occluded. Posterior tibial and anterior tibial arteries were graded as patent or occluded. Progression was defined as any increase in stenosis category. The mean follow-up period was 31 months for APL+ and 35 months for APL- patients (P = not significant). Progression of LEAOD occurred in 58 (73%) of 79 APL+ patients and in 25 (37%) of 68 APL- patients (P <.001). There was no difference in progression in external iliac or common femoral arteries. Differences in progression were noted in more distal arteries; APL+ patients had significantly more progression in superficial femoral (45% vs 16%, P <.01), popliteal (31% vs 12%, P <.01), posterior tibial (29% vs 13%, P <.05), and anterior tibial arteries (29% vs 14%, P <.05). Multivariate logistic regression analysis showed a significant independent

  8. Long-term cardiovascular effects of neonatal dexamethasone treatment: hemodynamic follow-up by left ventricular pressure-volume loops in rats.

    PubMed

    Bal, Miriam P; de Vries, Willem B; van Oosterhout, Matthijs F M; Baan, Jan; van der Wall, Ernst E; van Bel, Frank; Steendijk, Paul

    2008-02-01

    Dexamethasone is clinically applied in preterm infants to treat or prevent chronic lung disease. However, concern has emerged about adverse side effects. The cardiovascular short-term side effects of neonatal dexamethasone treatment are well documented, but long-term consequences are unknown. Previous studies showed suppressed mitosis during dexamethasone treatment, leading to reduced ventricular weight, depressed systolic function, and compensatory dilatation in prepubertal rats. In addition, recent data indicated a reduced life expectancy. Therefore, we investigated the long-term effects of neonatal dexamethasone treatment on cardiovascular function. Neonatal rats were treated with dexamethasone or received saline. Cardiac function was determined in 8-, 50-, and 80-wk-old animals, representing young adult, middle-aged, and elderly stages. A pressure-conductance catheter was introduced into the left ventricle to measure pressure-volume loops. Subsequently, the hearts were collected for histological examination. Our results showed reduced ventricular and body weights in dexamethasone-treated rats at 8 and 80 wk, but not at 50 wk. Cardiac output and diastolic function were unchanged, but systolic function was depressed at 50 and 80 wk, evidenced by reduced ejection fractions and rightward shifts of the end-systolic pressure-volume relationships. We concluded that previously demonstrated early adverse effects of neonatal dexamethasone treatment are transient but that reduced ventricular weight and systolic dysfunction become manifest again in elderly rats. Presumably, cellular hypertrophy initially compensates for the dexamethasone treatment-induced lower number of cardiomyocytes, but this mechanism falls short at a later stage, leading to systolic dysfunction. If applicable to humans, cardiac screening of a relatively large patient group to enable secondary prevention may be indicated.

  9. Experimental Investigation of Pressure-volume-Temperature Mass Gauging Method Under Microgravity Condition by Parabolic Flight

    NASA Astrophysics Data System (ADS)

    Seo, Mansu; Park, Hana; Yoo, DonGyu; Jung, Youngsuk; Jeong, Sangkwon

    Gauging the volume or mass of liquid propellant of a rocket vehicle in space is an important issue for its economic feasibility and optimized design of loading mass. Pressure-volume-temperature (PVT) gauging method is one of the most suitable measuring techniques in space due to its simplicity and reliability. This paper presents unique experimental results and analyses of PVT gauging method using liquid nitrogen under microgravity condition by parabolic flight. A vacuum-insulated and cylindrical-shaped liquid nitrogen storage tank with 9.2 L volume is manufactured by observing regulation of parabolic flight. PVT gauging experiments are conducted under low liquid fraction condition from 26% to 32%. Pressure, temperature, and the injected helium mass into the storage tank are measured to obtain the ullage volume by gas state equation. Liquid volume is finally derived by the measured ullage volume and the known total tank volume. Two sets of parabolic flights are conducted and each set is composed of approximately 10 parabolic flights. In the first set of flights, the short initial waiting time (3 ∼ 5 seconds) cannot achieve sufficient thermal equilibrium condition at the beginning. It causes inaccurate gauging results due to insufficient information of the initial helium partial pressure in the tank. The helium injection after 12 second waiting time at microgravity condition with high mass flow rate in the second set of flights achieves successful initial thermal equilibrium states and accurate measurement results of initial helium partial pressure. Liquid volume measurement errors in the second set are within 11%.

  10. Cardiac energetics: from E(max) to pressure-volume area.

    PubMed

    Suga, Hiroyuki

    2003-08-01

    1. To celebrate this Festschrift for Professor Colin Gibbs, as an invited speaker, I would like to review briefly my 35 year research career in cardiac physiology. 2. My career started in the late 1960s in Tokyo with my serendipitous discovery of Emax (ventricular end-systolic maximum elastance) as a load-independent contractility index based on the time-varying elastance (E(t)) model of the ventricle. Professor K Sagawa at the Johns Hopkins University, USA, whom I joined in 1971, encouraged me to go further. 3. The next serendipitous event in my career was the discovery of ventricular pressure-volume area (PVA) as a measure of total mechanical energy of ventricular contraction in the late 1970s. The PVA concept was theoretically deducible from the E(t) and Emax concept and correlated surprisingly well with ventricular O2 consumption (Vo2). 4. Professor Gibbs' intuitive recognition of the significance of PVA in myocardial energetics in the 1980-1990s greatly encouraged me thereafter. The third serendipitous event in my career occurred in the mid 1990s and was my discovery of a novel integrative analysis method to assess the total amount of Ca2+ recruited in each excitation-contraction coupling from the decay rate of postextrasystolic potentiation, taking advantage of the Emax-PVA-Vo2 framework. 5. I am now hoping to experience one more serendipitous experience by developing an integrative analysis method of cross-bridge cycling in a beating heart using the Emax and PVA concepts.

  11. [Clinical significance of dynamic pressure-volume curve in neonatal mechanical ventilation].

    PubMed

    Zhu, Yuan-Peng; Ma, Li-Ya; Wu, Zhi-Jun; Lu, Guang-Jin; Han, Yu-Kun

    2009-07-01

    To study the characteristics and role of dynamic pressure-volume curve (P-V curve) in neonatal mechanical ventilation. A dynamic P-V curve was automatically drawn by the Stephanie ventilator. The slope rate of dynamic P-V curve was measured in 25 neonates who received mechanical ventilation 1, 24, 48 and 72 hrs after ventilation and before weaning from ventilation. Minute-ventilation (MV), mean airway pressure (Pmean), and fraction of inspired oxygen (FiO2) were recorded. The patterns of dynamic P-V curve during abnormal ventilation (resistance to ventilator, part or complete airway obstruction, airway leaking and tracheal catheter exodus) were observed. With the improvement of pulmonary disease, the slope rate of P-V curve and MV increased, Pmean and FiO2 decreased, and the P-V curve shifted to the volume axle. The slope rate of curve 48 and 72 hrs after ventilation and before weaning from ventilation (1.05+/-0.48, 1.10+/-0.42 and 1.13+/-0.37 mL/cmH2O respectively) increased significantly compared with that 1 hr after ventilation (0.76+/-0.53 mL/cmH2O) (p<0.05 or 0.01). Abnormal ventilation led to abnormal appearance of dynamic P-V curve. The increasing slope rate of dynamic P-V curve and the curve shifting to volume axle in neonatal mechanical ventilation may be associated with the improvement of pulmonary disease. The appearance changes of the curve may be of value in the assessment of abnormal ventilation.

  12. Changes in the structure-function relationship of elastin and its impact on the proximal pulmonary arterial mechanics of hypertensive calves

    PubMed Central

    Lammers, Steven R.; Kao, Phil H.; Qi, H. Jerry; Hunter, Kendall; Lanning, Craig; Albietz, Joseph; Hofmeister, Stephen; Mecham, Robert; Stenmark, Kurt R.; Shandas, Robin

    2008-01-01

    Extracellular matrix remodeling has been proposed as one mechanism by which proximal pulmonary arteries stiffen during pulmonary arterial hypertension (PAH). Although some attention has been paid to the role of collagen and metallomatrix proteins in affecting vascular stiffness, much less work has been performed on changes in elastin structure-function relationships in PAH. Such work is warranted, given the importance of elastin as the structural protein primarily responsible for the passive elastic behavior of these conduit arteries. Here, we study structure-function relationships of fresh arterial tissue and purified arterial elastin from the main, left, and right pulmonary artery branches of normotensive and hypoxia-induced pulmonary hypertensive neonatal calves. PAH resulted in an average 81 and 72% increase in stiffness of fresh and digested tissue, respectively. Increase in stiffness appears most attributable to elevated elastic modulus, which increased 46 and 65%, respectively, for fresh and digested tissue. Comparison between fresh and digested tissues shows that, at 35% strain, a minimum of 48% of the arterial load is carried by elastin, and a minimum of 43% of the change in stiffness of arterial tissue is due to the change in elastin stiffness. Analysis of the stress-strain behavior revealed that PAH causes an increase in the strains associated with the physiological pressure range but had no effect on the strain of transition from elastin-dominant to collagen-dominant behavior. These results indicate that mechanobiological adaptations of the continuum and geometric properties of elastin, in response to PAH, significantly elevate the circumferential stiffness of proximal pulmonary arterial tissue. PMID:18660454

  13. Relationship of Plasma Adiponectin and Waist-hip Ratio with Coronary Artery Disease

    PubMed Central

    Rashiti, Premtim; Elezi, Shpend; Behluli, Ibrahim; Mucaj, Sefedin

    2016-01-01

    Background: This study aimed to investigate correlation between adiponectin and waist-hip-ratio with severity of coronary artery disease (CAD). There is uncertainty about the association between circulating concentrations of adiponectin and CAD. Methods: We enrolled eighty-two consecutive patients undergoing non-urgent coronary angiography for CAD survey. According to the angiography results, the patients were divided into two groups in 1:1 ratio patients admitted with a diagnosis of CAD and non-CAD. We conducted hospital based research, involving study group with documented angiographically CAD, and control group without evidence of CAD. Angiograms were also quantified for the extent and severity of CAD by the Gensini scoring system. We measured baseline adiponectin levels in stored serum samples of all patients, anthropometric and biochemical risk factors were assessed in both groups. Results: The presence of CAD was associated with current smoking, male gender, waist–hip ratio (WHR) and left ventricular ejection fraction (LVEF). Baseline adiponectin concentrations correlated significantly in terms of the lipid parameters, positively with HDL cholesterol concentrations (r=0.327, P=0.028, P<0.05) and serum triglyceride concentrations were correlated negatively (r=-0.513, P<0.001). No significant difference between median adiponectin levels at baseline was observed between cases and controls. Conclusion: There is a significant positive correlation between waist–hip ratio and presence and severity of coronary artery disease. In conclusion, there is a significant positive correlation between adiponectin and Gensini score among Kosovar patients. PMID:28210011

  14. Modelling of the dynamic relationship between arterial pressure, renal sympathetic nerve activity and renal blood flow in conscious rabbits.

    PubMed

    Berger, C S; Malpas, S C

    1998-12-01

    A linear autoregressive/moving-average model was developed to describe the dynamic relationship between mean arterial pressure (MAP), renal sympathetic nerve activity (SNA) and renal blood flow (RBF) in conscious rabbits. The RBF and SNA to the same kidney were measured under resting conditions in a group of eight rabbits. Spectral analysis of the data sampled at 0.4 Hz showed that the low-pass bandwidth of the signal power for RBF was approximately 0. 05 Hz. An autoregressive/moving-average model with an exogenous input (ARMAX) was then derived (using the iterative Gauss-Newton algorithm provided by the MATLAB identification Toolbox), with MAP and SNA as inputs and RBF as output, to model the low-frequency fluctuations. The model step responses of RBF to changes in SNA and arterial pressure indicated an overdamped response with a settling time that was usually less than 2 s. Calculated residuals from the model indicated that 79 5 % (mean s.d., averaged over eight independent experiments) of the variation in RBF could be accounted for by the variations in arterial pressure and SNA. Two additional single-input models for each of the inputs were similarly obtained and showed conclusively that changes in RBF, in the conscious resting rabbit, are a function of both SNA and MAP and that the SNA signal has the predominant effect. These results indicate a strong reliance on SNA for the dynamic regulation of RBF. Such information is likely to be important in understanding the diminished renal function that occurs in a variety of disease conditions in which overactivity of the sympathetic nervous system occurs.

  15. Assessment of computer-controlled inflation/deflation for determining the properties of PTCA balloon catheters with pressure-volume curves.

    PubMed

    Olbrich, T; Murray, A

    2001-05-01

    Restenosis is a significant problem after percutaneous transluminal coronary angioplasty (PTCA), leading to further angina or even death. The mechanisms causing restenosis are not well understood and the effect of the angioplasty balloon on the artery wall is generally unknown. The aim of the research presented here was to assess the repeatability with which measurements of balloon pressure-volume characteristics could be made, to ensure that different balloons could be distinguished easily, an essential first step before the arteries themselves could be characterized. An inflation/deflation device was inflated with and without an attached balloon under computer control at a constant speed to 8 bar. The accuracy and repeatability of the technique was assessed within a single measurement session and between measurement sessions on six separate days. For each measurement session, four repeated inflations/deflations were carried out and the average was determined. Compliance (volume change/pressure change), inflation volume and pressure drop at 8 bar were determined for various balloon catheters of different size, type and manufacturer. The system repeatability SD for measuring volume without a balloon was +/- 0.0005 ml within a single measurement session, and +/- 0.002 ml between independent days. With an attached balloon the repeatability SD for measuring volume was +/- 0.001 ml within, and +/- 0.003 ml between days. Compliance was determined with a repeatability SD of +/- 0.16 microliter bar-1 within, and +/- 0.94 microliter bar-1 between days. The inflation/deflation device and technique employed allowed small changes in volume and compliance to be differentiated. The system also enabled differences due to the material characteristics for different PTCA balloons to be determined. Measured balloon characteristics were similar to the data given by manufacturers. This gives confidence in development of the technique for clinical use.

  16. Pressure-volume loop-derived cardiac indices during dobutamine stress: a step towards understanding limitations in cardiac output in children with hypoplastic left heart syndrome.

    PubMed

    Wong, James; Pushparajah, Kuberan; de Vecchi, Adelaide; Ruijsink, Bram; Greil, Gerald F; Hussain, Tarique; Razavi, Reza

    2017-03-01

    Children with a single systemic right ventricle, such as in hypoplastic left heart syndrome (HLHS), frequently experience reduced exercise capacity. Elucidating the causes could help with optimising treatment strategies. Prospective data from 10 consecutive symptomatic patients with HLHS undergoing clinical cardiac magnetic resonance with catheterisation (XMR) were analysed. Mean age 8.6years (range 3.5-11.6years), mean time since Fontan completion 5.5years. MR-compatible catheters were placed in the systemic right ventricle and branch pulmonary arteries to record pressures at rest, with dobutamine infusion at 10mcg/kg/min and at 20mcg/kg/min. Cine short-axis stacks of the ventricle were performed at each condition and used to construct pressure-volume loops. Compared to rest, cardiac index increased with low-dose dobutamine (p<0.01) with no further rise at peak stress despite a further, albeit, blunted rise in heart rate (p=0.002). A fall in stroke volume occurred (p=0.014) despite good contractility (74% increase, p=0.045) and a well-coupled ventriculo-arterial ratio. End-diastolic pressure and early active relaxation, markers of diastolic function, were normal at rest. However, preload fell at peak stress (p<0.008) while pulmonary vascular resistance (PVR) was low throughout. This group of HLHS patients demonstrated a fall in SV at peak stress, coinciding with a fall in preload. Markers of systolic and diastolic function remained normal. Failure to adequately fill the ventricle implies a ceiling of maximal flow through the Fontan circuit despite low PVR. Copyright © 2016. Published by Elsevier B.V.

  17. Gross anatomical study on the human myocardial bridges with special reference to the spatial relationship among coronary arteries, cardiac veins, and autonomic nerves.

    PubMed

    Watanabe, Yuko; Arakawa, Takamitsu; Kageyama, Ikuo; Aizawa, Yukio; Kumaki, Katsuji; Miki, Akinori; Terashima, Toshio

    2016-04-01

    Coronary arteries are frequently covered by cardiac muscles. This arrangement is termed a myocardial bridge. Previous studies have shown that myocardial bridges can cause myocardial ischemic diseases or cardiac arrhythmia, but the relevant pathogenic mechanisms remain unknown. We examined 60 hearts from Japanese cadavers macroscopically to clarify the spatial relationships among coronary arteries, cardiac veins and autonomic nerves. We found 86 myocardial bridges in 47 hearts from the 60 cadavers examined (78.3%). Next, we dissected out nine hearts with myocardial bridges in detail under the operating microscope. We found no additional branches of coronary arteries on the myocardial bridge surfaces. However, the cardiac veins, which usually accompany the coronary arteries, ran independently on the myocardial bridge surfaces in the same region. Cardiac autonomic nerves comprised two rami: one was associated with the coronary artery under the myocardial bridge and the other ran on the surface of the bridge. Such spatial relationships among the coronary arteries, cardiac veins and cardiac autonomic nerves at the myocardial bridges are quite similar to those in mouse embryo hearts. © 2015 Wiley Periodicals, Inc.

  18. Relationship between inter-arm blood pressure differences and future cardiovascular events in coronary artery disease.

    PubMed

    Tokitsu, Takanori; Yamamoto, Eiichiro; Hirata, Yoshihiro; Fujisue, Koichiro; Sugamura, Koichi; Maeda, Hirofumi; Tsujita, Kenichi; Kaikita, Koichi; Hokimoto, Seiji; Sugiyama, Seigo; Ogawa, Hisao

    2015-09-01

    Recent studies have shown that inter-arm blood pressure differences (IAD) may be a risk factor for cardiovascular events; however, none have addressed them in patients with coronary artery disease (CAD). We measured blood pressure bilaterally with the ankle brachial index (ABI) in 657 patients with suspected CAD and assessed the presence of CAD by coronary angiography, and the severity of coronary atherosclerosis with the Gensini score. Mean IADs were significantly greater in risk factor matched patients with CAD than in those without it (P = 0.01), whereas Gensini scores were significantly greater in those with high IAD (≥10  mmHg) than in those with low-IAD (P = 0.01) according to cross-sectional analysis. Patients with high IAD had a significantly greater probability of cardiovascular events than those in whom it was low (log-rank test, P < 0.01, mean follow-up range; 827.3 ± 268.1 days). The presence of hypertension, ABI, usage of calcium channel blocker and high IAD were independent predictors of cardiovascular events according to longitudinal analysis (IAD; hazard ratio: 2.90, 95% confidence interval: 1.41-5.94, P < 0.01) in these patients. Patients with high IAD and peripheral artery disease had the highest Gensini scores according to cross-sectional analysis (P < 0.01) and highest probability of cardiovascular events according to longitudinal analysis (log-rank test, P < 0.001). IADs were increased in CAD patients and correlated with its severity. Greater than 10  mmHg of IAD was independently associated with future cardiovascular events. Assessing IAD by ABI measurement may facilitate risk stratification in CAD patients.

  19. An exploration of the relationship between coronary artery bypass graft patients' self-sought educational resources and outcomes.

    PubMed

    Fredericks, Suzanne; Sidani, Souraya

    2008-01-01

    Postoperative coronary artery bypass graft (CABG) patients seek educational resources around discharge. There is limited research on the type and perceived effectiveness of self-sought educational resources. The purpose of this study was to describe the use of self-sought educational resources by patients around time of discharge and to explore relationships between use of self-sought educational resources and self-care knowledge, performance of self-care behavior, and symptom frequency. This study is a substudy of a randomized clinical trial that included a convenience sample of first-time CABG patients. Significant correlations were found between use of self-sought educational resources and greater frequency of patient's behavior (P

  20. Simultaneous pressure-volume measurements using optical sensors and MRI for left ventricle function assessment during animal experiment.

    PubMed

    Abi-Abdallah Rodriguez, Dima; Durand, Emmanuel; de Rochefort, Ludovic; Boudjemline, Younes; Mousseaux, Elie

    2015-01-01

    Simultaneous pressure and volume measurements enable the extraction of valuable parameters for left ventricle function assessment. Cardiac MR has proven to be the most accurate method for volume estimation. Nonetheless, measuring pressure simultaneously during MRI acquisitions remains a challenge given the magnetic nature of the widely used pressure transducers. In this study we show the feasibility of simultaneous in vivo pressure-volume acquisitions with MRI using optical pressure sensors. Pressure-volume loops were calculated while inducing three inotropic states in a sheep and functional indices were extracted, using single beat loops, to characterize systolic and diastolic performance. Functional indices evolved as expected in response to positive inotropic stimuli. The end-systolic elastance, representing the contractility index, the diastolic myocardium compliance, and the cardiac work efficiency all increased when inducing inotropic state enhancement. The association of MRI and optical pressure sensors within the left ventricle successfully enabled pressure-volume loop analysis after having respective data simultaneously recorded during the experimentation without the need to move the animal between each inotropic state. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  1. Anatomic Relationship of the Internal Jugular Vein and the Common Carotid Artery Applied to Percutaneous Transjugular Procedures

    SciTech Connect

    Turba, Ulku C.; Uflacker, Renan Hannegan, Christopher; Selby, J. Bayne

    2005-04-15

    Purpose. To demonstrate the anatomic relationship of the internal jugular vein (IJV) with the common carotid artery (CCA) in order to avoid inadvertent puncture of the CCA during percutaneous central venous access or transjugular interventional procedures. Methods. One hundred and eighty-eight consecutive patients requiring either central venous access or interventional procedures via the IJV were included in the analysis. The position of the IJV in relation to the CCA was demonstrated by portable ultrasonography. The IJV location was recorded in a clock-dial system using the carotid as the center of the dial and the angles were measured. Outcomes of the procedure were also recorded. Results. The IJV was lateral to the CCA in 187 of 188 patients and medial to the CCA in one patient. The left IJV was at the 12 o'clock position in 12 patients (6%), the 11 o'clock position in 17 patients (9%), the 10 o'clock position in 142 patients (75%) and at the 9 o'clock position in 17 patients (9%). The right IJV was at the 12 o'clock position in 8 patients (4%), the 1 o'clock position in 31 patients (16%), the 2 o'clock position in 134 patients (71%) and the 3 o'clock position in 17 patients (9%). In one patient the left IJV was located approximately 60 deg. medial to the left CCA; this was recorded as 2 o'clock on the left since it is opposite to the 10 o'clock position. Conclusion. Knowledge of the IJV anatomy and relationship to the CCA is important information for the operator performing an IJV puncture, to potentially reduce the chance of laceration of the CCA and avoid placement of a large catheter within a critical artery, even when ultrasound guidance is used.

  2. An objective analysis of the pressure-volume curve in the acute respiratory distress syndrome.

    PubMed

    Harris, R S; Hess, D R; Venegas, J G

    2000-02-01

    To assess the interobserver and intraobserver variability in the clinical evaluation of the quasi-static pressure-volume (P-V) curve, we analyzed 24 sets of inflation and deflation P-V curves obtained from patients with ARDS. We used a recently described sigmoidal equation to curve-fit the P-V data sets and objectively define the point of maximum compliance increase of the inflation limb (P(mci, i)) and the true inflection point of the deflation limb (P(inf,d)). These points were compared with graphic determinations of lower Pflex by seven clinicians. The graphic and curve-fitting methods were also compared for their ability to reproduce the same parameter value in data sets with reduced number of data points. The sigmoidal equation fit the P-V data with great accuracy (R(2) = 0.9992). The average of Pflex determinations was found to be correlated with P(mci,i) (R = 0.89) and P(inf,d) (R = 0.76). Individual determinations of Pflex were less correlated with the corresponding objective parameters (R = 0.67 and 0.62, respectively). Pflex + 2 cm H(2)O was a more accurate estimator of P(inf,d) (2 SD = +/-6.05 cm H(2)O) than Pflex was of P(mci,i) (2 SD = +/-8.02 cm H(2)O). There was significant interobserver variability in Pflex, with a maximum difference of 11 cm H(2)O for the same patient (SD = 1.9 cm H(2)O). Clinicians had difficulty reproducing Pflex in smaller data sets with differences as great as 17 cm H(2)O (SD = 2.8 cm H(2)O). In contrast, the curve-fitting method reproduced P(mci,i) with great accuracy in reduced data sets (maximum difference of 1.5 cm H(2)O and SD = 0.3 cm H(2)O). We conclude that Pflex rarely coincided with the point of maximum compliance increase defined by a sigmoid curve-fit with large differences in Pflex seen both among and within observers. Calculating objective parameters such as P(mci,i) or P(inf,d) from curve-fitted P-V data can minimize this large variability.

  3. Effect of Sildenafil on Pressure-Volume Loop Measures of Ventricular Function in Fontan Patients.

    PubMed

    Butts, Ryan J; Chowdhury, Shahryar M; Baker, George H; Bandisode, Varsha; Savage, Andrew J; Atz, Andrew M

    2016-01-01

    Sildenafil has been reported to improve exercise capacity in Fontan patients, but the physiologic mechanisms behind these findings are not completely understood. The objective of this study was to study the acute effect of sildenafil on pressure-volume loop (PVL) measures of ventricular function in Fontan patients. Patients after Fontan operation who were presenting for a clinically indicated catheterization were enrolled. Patients were randomized in a double-blinded fashion to receive placebo (n = 9) or sildenafil (n = 10) 30-90 min prior to catheterization. PVLs were recorded using microconductance catheters at baseline and after infusion of dobutamine (10 mcg/kg/min). The primary outcome was change in ventriculoarterial (VA) coupling. For the entire cohort, VA coupling trended toward improvement with dobutamine (1.4 ± 0.4 to 1.8 ± 0.9, p = 0.07). End-systolic elastance showed improvement (2.6 ± 0.9 to 3.8 ± 1.4 mmHg m(2)/ml, p < 0.01) with dobutamine infusion. The cohorts had similar VA coupling at baseline (p = 0.32), but the sildenafil cohort trended toward having less of an improvement in VA coupling with dobutamine stress (p = 0.06). There were no differences between PVL measures of systolic or diastolic function between treatment groups, both at baseline and after dobutamine infusion. Patients with Fontan circulation had improved contractility and trended toward improvement in VA coupling with dobutamine stress. Acute sildenafil administration was not associated with improved PVL measurements of ventricular function in this population. These results suggest that clinical improvements seen with administration of sildenafil in Fontan patients are not associated with an acute improvement in ventricular function. www.clinicaltrials.gov ; Clinicaltrials.gov Identifier: NCT01815502.

  4. The effect of nimodipine on intracranial pressure. Volume-pressure studies in a primate model.

    PubMed

    Hadley, M N; Spetzler, R F; Fifield, M S; Bichard, W D; Hodak, J A

    1987-09-01

    Nimodipine was administered by intravenous infusion to six male baboons before, during, and after 6 hours of middle cerebral artery occlusion. Intracranial pressure (ICP) and systemic blood pressure were monitored continuously. An epidural balloon was inflated at regular intervals at three levels of arterial CO2 tension (25, 35, and 50 mm Hg) before and after the administration of nimodipine, and volume-pressure curves were generated. In every case, curves generated after intravenous nimodipine infusion were lower and shifted more to the right than the same set of curves generated before nimodipine administration, regardless of the baseline ICP. The reduction in ICP following nimodipine infusion was not due to a reduction in mean arterial blood pressure and was statistically significant at all three levels of pCO2 (p less than 0.01). These results suggest that, in the presence of elevated ICP due to cerebral infarction, there is no increased risk of exacerbating intracranial hypertension with the addition of nimodipine.

  5. Relationship between arterial blood pressure and blood viscosity in spontaneously hypertensive rats treated with pentoxifylline.

    PubMed

    Plotnikov, Mark B; Aliev, Oleg I; Nosarev, Alexey V; Shamanaev, Alexander Y; Sidekhmenova, Anastasia V; Anfinogenova, Yana; Anishchenko, Anna M; Pushkina, Ekaterina V

    2016-07-26

    Systemic arterial pressure (AP) depends on two physiological variables: cardiac output (CO) and total peripheral resistance (TPR). The latter depends on vascular hindrance and blood viscosity (BV). However, the relative contributions of the vascular and rheological factors to TPR remain unclear. The aim of our work was to study the haemodynamic and haemorheologic effects of a treatment course with pentoxifylline (PTX) in SHRs in an effort to assess the impact of the rheological factor on TPR and AP. The effects of the treatment course with PTX (100 mg/kg/day p.o. for six weeks) on BV, plasma viscosity, haematocrit, erythrocyte aggregation and deformability, mean AP (MAP), stroke volume (SV), CO, and TPR were studied in SHRs and in control Wistar Kyoto (WKY) rats. PTX-treated SHRs had a lower BV, lower erythrocyte aggregation, and higher erythrocyte deformability index compared with the controls. The TPR level was higher by 43% compared with that in WKY rats and did not differ from the values obtained from control SHRs. In SHRs, moderate and strong positive correlations were found between BV and MAP and between BV and TPR. PTX-treated SHRs did not have any significant correlations between the above mentioned parameters. Treatment with PTX attenuated whole blood viscosity, but did not affect the AP and hemodynamic parameters in the experimental SHRs compared with the control SHRs. The magnitude of the rheologic effects of PTX was insufficient to cause appreciable decreases in TPR and AP.

  6. Relationship between arterial vascular calcifications seen on screening mammograms and biochemical markers of endothelial injury.

    PubMed

    Pidal, Diego; Sánchez Vidal, M Teresa; Rodríguez, Juan Carlos; Corte, M Daniela; Pravia, Paz; Guinea, Oscar; Pidal, Iván; Bongera, Miguel; Escribano, Dámaso; González, Luis O; Díez, M Cruz; Venta, Rafael; Vizoso, Francisco J

    2009-01-01

    To assess whether breast arterial calcifications (BAC) are associated with altered serum markers of cardiovascular risk, mammograms and records from 1759 women (age range: 45-65 years) screened for breast cancer were revised. One hundred and forty seven (8.36%) women showed BAC. A total of 136 women with BAC and controls (mean age: 57 and 55 years, respectively) accepted entering the study. There were no significant differences in serum levels of urea, glucose, uric acid, creatinine, total cholesterol, HDL-C, LDL-C, folic acid, vitamin B(12), TSH or cysteine, between both groups of patients. However, women with BAC showed higher serum levels of triglycerides (p=0.006), homocysteine (p=0.002) and hs-CRP (p=0.003) than women without BAC. Likewise, we found a significantly higher percentage of cases with an elevated LDL-C/HDL-C ratio (coronary risk index >2) amongst women with BAC than in women without BAC (56.7 and 38.2%, respectively; p=0.04). Our results indicate that the finding of BAC identify women showing altered serum markers of cardiovascular risk.

  7. Fatty Liver, Insulin Resistance, and Obesity: Relationships With Increase in Coronary Artery Calcium Over Time.

    PubMed

    Sung, Ki-Chul; Ryu, Seungho; Lee, Jong-Young; Lee, Sung Ho; Cheong, Eun Sun; Wild, Sarah H; Byrne, Christopher D

    2016-06-01

    Nonalcoholic fatty liver disease, insulin resistance (IR), and obesity frequently coexist with type 2 diabetes mellitus (DM), but it is uncertain whether these risk factors for vascular disease contribute to a change in atherosclerosis over time, independently of DM status. We hypothesized that the combination of fatty liver, IR, and obesity would be associated with an increase in coronary artery calcium (CAC) score over time, independently of DM status, other cardiovascular risk factors, and medications. Data were analyzed from a South Korean occupational cohort of 2175 people. The outcome was increase in cardiac computed tomography CAC score between baseline and follow-up. Insulin resistance was defined by homeostatic model assessment of insulin resistance (HOMA-IR) ≥75th percentile and fatty liver by ultrasound. In 592 (27.2%) participants, CAC score increased from baseline (mean ± SD; mean age at baseline, 44.8 ± 5.5 years); and in 1583 subjects, CAC did not change or improved during follow-up (mean age, 41.6 ± 5.6 years). Diabetes mellitus, HOMA-IR, fatty liver, and obesity prevalence were all higher (all P < 0.001) in participants whose CAC score increased from baseline. Adjusting for DM and potential confounders, the combination of IR, obesity, and fatty liver was independently associated with increase in CAC score over time (hazard ratio: 2.46, 95% confidence interval: 1.50-4.03). The combination of fatty liver, IR, and obesity is associated with progression of atherosclerosis over time independently of DM, cardiovascular risk factors, and all medications for cardiovascular disease and DM. © 2016 Wiley Periodicals, Inc.

  8. Additive relationship between serum fibroblast growth factor 21 level and coronary artery disease

    PubMed Central

    2013-01-01

    Background Expression and activity of the fibroblast growth factor (FGF) 21 hormone-like protein are associated with development of several metabolic disorders. This study was designed to investigate whether serum FGF21 level was also associated with the metabolic syndrome-related cardiovascular disease, atherosclerosis, and its clinical features in a Chinese cohort. Methods Two-hundred-and-fifty-three subjects visiting the Cardiology Department (Sixth People's Hospital affiliated to Shanghai JiaoTong University) were examined by coronary arteriography (to diagnose coronary artery disease (CAD)) and hepatic ultrasonography (to diagnose non-alcoholic fatty liver disease (NAFLD)). Serum FGF21 level was measured by enzyme-linked immunosorbent assay and analyzed for correlation to subject and clinical characteristics. The independent factors of CAD were determined by multivariate logistic regression analysis. Results Subjects with NAFLD showed significantly higher serum FGF21 than those without NAFLD (388.0 pg/mL (253.0-655.4) vs. 273.3 pg/mL (164.9-383.7), P < 0.01). Subjects with CAD showed significantly higher serum FGF21, regardless of NAFLD diagnosis (P < 0.05). Serum FGF21 level significantly elevated with the increasing number of metabolic disorders (P for trend < 0.01). After adjustment of age, sex, and BMI, FGF21 was positively correlated with total cholesterol (P < 0.05) and triglyceride (P < 0.01). FGF21 was identified as an independent factor of CAD (odds ratio = 2.984, 95% confidence interval: 1.014-8.786, P < 0.05). Conclusions Increased level of serum FGF21 is associated with NAFLD, metabolic disorders and CAD. PMID:23981342

  9. ApoE gene polymorphism and its relationship with coronary artery disease in ethnic Kashmiri population.

    PubMed

    Afroze, Dil; Yousuf, Adfar; Tramboo, Nisar A; Shah, Zaffar A; Ahmad, Asrar

    2016-11-01

    Apolipoprotein E is a fundamental component of various lipoproteins and plays substantial role in cholesterol/lipid transport among cells of various tissues. The ApoE gene is polymorphic with three alleles ε2, ε3, and ε4, coding for isoforms E2, E3, and E4 having different binding inclination for corresponding receptors. This work aimed to investigate the association between ApoE gene polymorphism and coronary artery disease (CAD) in Kashmiri population. APOE genotyping was done by polymerase chain reaction-restriction fragment length polymorphism. Our study indicated ApoE ε3/ε3 to be the most common genotype in both CAD and control group. The frequency of ε2, ε3, and ε4 alleles of ApoE gene in cases was observed to be 0.06, 0.72, and 0.20, while in control subjects it was 0.075, 0.82, and 0.11, respectively. A significant difference was found between cases and controls with respect to TC, LDL, and HDL levels. Our data showed that frequency of ε4/ε4, ε4/ε3 genotype and ε4 allele was significantly higher in cases than in controls (p = 0.02, p = 0.004, p < 0.001 respectively). Moreover, the CAD patients carrying ε4 allele had significantly higher TC and LDL levels (p value <0.01). Thus our data showed a significant association of ApoE ε4 allele with the risk of CAD. The data revealed that ApoE ε4 allele is associated with increased risk of CAD and increased levels LDL and TC in Kashmiri population.

  10. Relationship of Insulin Resistance and Related Metabolic Variables to Coronary Artery Disease: A Mathematical Analysis

    PubMed Central

    Eddy, David; Schlessinger, Len; Kahn, Richard; Peskin, Barbara; Schiebinger, Rick

    2009-01-01

    OBJECTIVE—People with diabetes have an increased risk of coronary artery disease (CAD). An unanswered question is what portion of CAD can be attributed to insulin resistance, related metabolic variables, and other known CAD risk factors. RESEARCH DESIGN AND METHODS—The Archimedes model was used to estimate the proportion of myocardial infarctions that would be prevented by maintaining insulin resistance and other risk factors at healthy levels. Person-specific data from the National Health and Nutrition Examination Survey 1998–2004 were used to create a simulated population representative of young adults in the U.S. This population was then entered into a series of simulated clinical trials designed to explore the effects of each risk factor. Each trial had a control arm (all risk factors were allowed to progress without interventions) and a treatment arm (a risk factor was held to its value in young healthy adults). The trials continued for 60 years. The effects of these hypothetical “cures” of each risk factor provide estimates of their impact on CAD. RESULTS—In young adults, preventing insulin resistance would prevent ∼42% of myocardial infarctions. The next most important determinant of CAD is systolic hypertension, prevention of which would reduce myocardial infarctions by ∼36%. Following systolic blood pressure, the most important determinants are HDL cholesterol (31%), BMI (21%), LDL cholesterol (16%), triglycerides (10%), fasting plasma glucose and smoking (both ∼9%), and family history (4%). CONCLUSIONS—Insulin resistance is likely the most important single cause of CAD. A better understanding of its pathogenesis and how it might be prevented or cured could have a profound effect on CAD. PMID:19017770

  11. Relationship of socioeconomic status to C-reactive protein and arterial stiffness in urban Japanese civil servants.

    PubMed

    Saijo, Yasuaki; Yoshioka, Eiji; Fukui, Tomonori; Kawaharada, Mariko; Kishi, Reiko

    2008-09-01

    This study investigates whether the two socioeconomic status indicators, educational level and employment grade, are associated with C-reactive protein (CRP) levels and arterial stiffness among Japanese urban civil servants. Brachial-ankle pulse-wave velocity (baPWV) as an indicator of arterial stiffness, CRP, occupational stress and conventional risk factors were evaluated in 3412 men and 854 women. Although the socioeconomic gradient showed a significant association with the CRP levels in men after adjustment for age, the significance disappeared after multivariate adjustment, whereas in women, the socioeconomic gradient showed no significant association with the CRP levels. In men, educational level was significantly associated with the baPWV value after adjustment for conventional risk factors, CRP and occupational stress (P for trend <0.0001). With regards to employment grade, only low-level non-manual workers had a significantly lower baPWV value as compared to manual workers at a fully adjusted model, and trend significance disappeared. However, in women, neither educational level nor employment grade was associated with the baPWV value. In summary, the socioeconomic gradient, especially the educational level, was significantly inversely related to the baPWV value in men. In women, the socioeconomic gradient was not related to the baPWV value. An inverse relationship between the socioeconomic gradient and CRP levels was found in men only after age adjustment. We suggest that because the educational level is an important aspect in the adolescent environment and hence might influence the future lifestyle, early health education should be provided to prevent an unfavourable lifestyle and atherosclerotic diseases in later life.

  12. Relationship of A1 segment hypoplasia to anterior communicating artery aneurysm morphology and risk factors for aneurysm formation.

    PubMed

    Rinaldo, Lorenzo; McCutcheon, Brandon A; Murphy, Meghan E; Bydon, Mohamad; Rabinstein, Alejandro A; Lanzino, Giuseppe

    2016-09-30

    OBJECTIVE Hypoplasia of the A1 segment of the anterior cerebral artery is frequently observed in patients with anterior communicating artery (ACoA) aneurysms. The effect of this anatomical variant on ACoA aneurysm morphology is not well understood. METHODS Digital subtraction angiography images were reviewed for 204 patients presenting to the authors' institution with either a ruptured or an unruptured ACoA aneurysm. The ratio of the width of the larger A1 segment to the smaller A1 segment was calculated. Patients with an A1 ratio greater than 2 were categorized as having A1 segment hypoplasia. The relationship of A1 segment hypoplasia to both patient and aneurysm characteristics was then assessed. RESULTS Of 204 patients that presented with an ACoA aneurysm, 34 (16.7%) were found to have a hypoplastic A1. Patients with A1 segment hypoplasia were less likely to have a history of smoking (44.1% vs 62.9%, p = 0.0410). ACoA aneurysms occurring in the setting of a hypoplastic A1 were also found to have a larger maximum diameter (mean 7.7 vs 6.0 mm, p = 0.0084). When considered as a continuous variable, increasing A1 ratio was associated with decreasing aneurysm dome-to-neck ratio (p = 0.0289). There was no significant difference in the prevalence of A1 segment hypoplasia between ruptured and unruptured aneurysms (18.9% vs 10.7%; p = 0.1605). CONCLUSIONS Our results suggest that a hypoplastic A1 may affect the morphology of ACoA aneurysms. In addition, the relative lack of traditional risk factors for aneurysm formation in patients with A1 segment hypoplasia argues for the importance of hemodynamic factors in the formation of ACoA aneurysms in this anatomical setting.

  13. Relationship of serum osteoprotegerin with arterial stiffness, preclinical atherosclerosis, and disease activity in patients with ankylosing spondylitis.

    PubMed

    Serdaroğlu Beyazal, Münevver; Erdoğan, Turan; Türkyılmaz, Aysegül Kücükali; Devrimsel, Gül; Cüre, Medine Cumhur; Beyazal, Mehmet; Sahin, Ismail

    2016-09-01

    Patients with ankylosing spondylitis (AS) reportedly have a higher mortality and morbidity risk. Osteoprotegerin (OPG) was recently defined as an important cardiovascular (CV) marker in the general population. We aimed to assess the relationship of serum OPG levels with arterial stiffness, carotid intima media thickness (CIMT), and clinical and laboratory data in AS patients. We examined 60 AS patients without CV disease or risk factors and 50 healthy controls. Disease activity was evaluated using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS), whereas functional capacity was evaluated using the Bath Ankylosing Spondylitis Functional Index (BASFI). Serum OPG levels were measured with the enzyme-linked immunosorbent assay. Carotid-femoral pulse wave velocity (PWV) was used as an indicator of arterial stiffness, whereas CIMT (examined via carotid ultrasonography) was used to evaluate preclinical atherosclerosis. The mean serum OPG level, PWV, and CIMT were significantly higher in AS patients than in controls (106.7 ± 50.9 vs. 58.1 ± 12.7 pg/mL; 7.4 ± 1.8 vs. 6.2 ± 1.2 m/s; 0.72 ± 0.13 vs. 0.57 ± 0.07 mm, respectively; P < 0.001 for all). In AS patients, the serum OPG levels were not significantly correlated with PWV and CIMT but were significantly correlated with erthrocyte sedimentation rate, BASFI, and ASDAS. AS patients without CV disease or risk exhibited high OPG levels and increased PWV and CIMT values. Although OPG levels were not significantly correlated with PWV or CIMT, future long-term follow-up studies will help define the predictive value of OPG in these patients.

  14. The Relationship between Vitamin D and Coronary Artery Ectasia in Subjects with a Normal C-Reactive Protein Level

    PubMed Central

    Cagirci, Goksel; Yuksel, Isa Oner; Bayar, Nermin; Koklu, Erkan; Guven, Ramazan; Arslan, Sakir

    2017-01-01

    Background and Objectives Vitamin D is generally known to be closely related to inflammation. The effects of vitamin D on coronary artery disease (CAD) are not fully explained. Nowadays, coronary artery ectasia (CAE) cases are common and are regarded as being a kind of CAD. We aimed to investigate, in a case-control study, the relationship between vitamin D and CAE without an associated inflammatory process. Subjects and Methods This study population included 201 patients (CAE group, 121 males; mean age, 61.2±6.4 years) with isolated CAE; and 197 healthy individuals (control group, 119 males; mean age, 62.4±5.8 years), comprising the control group, who had normal coronary arteries. These participants concurrently underwent routine biochemical tests, tests for inflammatory markers, and tests for 25-OH vitamin D in whole-blood draws. These parameters were compared. Results There are no statistical significance differences among the groups for basic clinical characteristics (p>0.05). Inflammatory markers were recorded and compared to exclude any inflammatory process. All of them were similar, and no statistical significance difference was found. The average parathyroid hormone (PTH) level of patients was higher than the average PTH level in controls (41.8±15.1 pg/mL vs. 19.1±5.81 pg/mL; p<0.001). Also, the average 25-OH vitamin D level of patients was lower than the average 25-OH vitamin D level of controls (14.5±6.3 ng/mL vs. 24.6±9.3 ng/mL; p<0.001). In receiver operating characteristic curve analysis, the observed cut-off value for vitamin D between the control group and patients was 10.8 and 85.6% sensitivity and 75.2% specificity (area under the curve: 0.854, 95% confidence interval: 0.678-0.863). Conclusion We found that there is an association between vitamin D and CAE in patients who had no inflammatory processes. Our study may provide evidence for the role of vitamin D as a non-inflammatory factor in the pathophysiology of CAE. PMID:28382079

  15. Age and cigarette smoking modulate the relationship between pulmonary function and arterial stiffness in heart failure patients

    PubMed Central

    Li, Li; Hu, Bangchuan; Gong, Shijin; Yu, Yihua; Yan, Jing

    2017-01-01

    Abstract The aim of this study was to assess the relationship between arterial stiffness and pulmonary function in chronic heart failure (CHF). Outpatients previously diagnosed as CHF were enrolled between April 2008 and March 2010, and submitted to arterial stiffness measurement and lung function assessment. Spirometry was performed by measuring forced vital capacity (FVC), the fraction of predicted FVC, forced expiratory volume in 1 second (FEV1), the percentage of predicted FEV1 in 1 second, FEV1 to FVC ratio, and the percentage of predicted FEV1/FVC. Cardio-ankle vascular index (CAVI) was considered for the estimation of arterial stiffness. The 354 patients assessed included 315 nonsmokers, and were 68.2 ± 7.2 years’ old. Unadjusted correlation analyses demonstrated CAVI was positively related to age (r = 0.3664, P < 0.0001), and negatively related to body mass index (BMI, r = −0.2040, P = 0.0001), E/A ratio (r = −0.1759, P = 0.0010), and FEV1 (r = −0.2987, P < 0.0001). Stepwise multivariate regression analyses showed age (r2 = 0.2391, P < 0.0001), BMI (r2 = −0.2139, P < 0.0001), smoking (r2 = 0.1211, P = 0.0130), E/A ratio (r2 = −0.1082, P = 0.0386), and FEV1 (r2 = −0.2550, P < 0.0001) were independent determinants of CAVI. In addition, there is a significant interaction between CAVI and forced expiratory volume in 1 second (FEV1) in relation to age (Pint < 0.0001) and smoking (Pint = 0.0001). Meanwhile, pulmonary function was not associated with BMI or E/A ratio. These findings demonstrated that reduced pulmonary function is associated with the increased CAVI, and had an interactive effect with age and smoking on CAVI in patients with CHF. PMID:28272233

  16. Current and adolescent body fatness and fat distribution: relationships with carotid intima-media thickness and large artery stiffness at the age of 36 years.

    PubMed

    Ferreira, Isabel; Twisk, Jos W R; van Mechelen, Willem; Kemper, Han C G; Seidell, Jacob C; Stehouwer, Coen D A

    2004-01-01

    Body fat and its distribution are determinants of cardiovascular disease but the underlying mechanisms of these adverse effects are poorly understood. We therefore investigated (1) the cross-sectional relationship between estimates of body fatness and its distribution on the one hand and carotid atherosclerosis and stiffness of the carotid, femoral and brachial arteries and the carotido-femoral segment on the other (336 subjects, 175 women); (2) the relationship between estimates of body fatness and its distribution during adolescence (13-16 years) and the same arterial properties at age 36- prospective analyses (subpopulation of 159 subjects, 84 girls). Cross-sectional and prospective analyses within an ongoing observational longitudinal study: The Amsterdam Growth and Health Longitudinal Study. Body fatness and its distribution were assessed by anthropometry and dual-energy X-ray absorptiometry (DXA); arterial properties were assessed non-invasively by ultrasound imaging. Total adiposity and, in men, truncal subcutaneous fat accumulation during adolescence, were positively and independently associated with carotid intima-media thickness at age 36, a pre-clinical indicator of atherosclerosis. Adolescent truncal subcutaneous fat accumulation but not total adiposity was associated with increased arterial stiffness at age 36. At age 36, both abdominal and truncal subcutaneous fat were independently associated with arterial stiffness, while the associations between total adiposity and arterial stiffness appeared to be mediated by other cardiovascular risk factors. Body fatness and body fat distribution are associated with large artery structural and functional properties at age 36 and the roots of these associations may already be present in adolescence.

  17. Ethnic differences in the relationship between pericardial adipose tissue and coronary artery calcified plaque: African-American-diabetes heart study.

    PubMed

    Divers, Jasmin; Wagenknecht, Lynne E; Bowden, Donald W; Carr, J Jeffrey; Hightower, R Caresse; Register, Thomas C; Xu, Jianzhao; Langefeld, Carl D; Freedman, Barry I

    2010-12-01

    Calcified atherosclerotic plaque (CP) is less prevalent and less severe in African-Americans (AA), relative to European Americans (EA). Because pericardial adipose tissue (PAT) is associated with CP in the neighboring coronary arteries, we explored ethnic-specific relationships between PAT and CP. PAT volume and coronary and aortic CP were measured in 561 EA and 575 AA subjects with type 2 diabetes using single and multidetector computed tomography. Generalized estimating equations with exchangeable correlation and the sandwich estimator of the variance were used to test for associations between PAT and CP. Mean (sd) ages of AA and EA participants were 56.7 (9.5) and 62.0 (8.9) yr, respectively; diabetes duration was 10.5 (8.1) and 10.1 (7.3) yr; and PAT volume was 86.9 (38.6) and 131.7 (55.3) cm3/45 mm. In AA and EA participants, respectively, mean (sd) coronary CP mass scores were 803 (1,889) and 1,465 (2,847) mg calcium; and aortic CP, 5,407 (10,651) and 10,090 (15,087) mg calcium. Adjusting for age, gender, body mass index, blood pressure, height, smoking, lipid-lowering medications, C-reactive protein, albuminuria, high-density lipoprotein-cholesterol, and triglycerides, parameter estimates for the relationship between PAT and log(coronary CP+1) were 0.012 in AA (P<0.0001) and 0.003 (P=0.24) in EA, with a significant ethnic difference (P=0.019). No significant relationships or ethnic differences were observed between PAT and aortic CP (P=0.24, fully adjusted model). Pericardial adiposity is strongly associated with coronary atherosclerosis in AA with type 2 diabetes. Novel cardiovascular disease risk factors such as PAT may contribute to ethnic disparities in susceptibility to development of coronary atherosclerosis.

  18. Chronic hypoxia augments uterine artery distensibility and alters the circumferential wall stress-strain relationship during pregnancy.

    PubMed

    Mateev, Stephanie N; Mouser, Rhonda; Young, David A; Mecham, Robert P; Moore, Lorna G

    2006-06-01

    Pregnancy-associated increases in uterine artery (UA) blood flow are due, in part, to vasoactive and growth-related changes that enlarge UA diameter. Although active and passive mechanical factors can contribute to this enlargement, their role is less well understood. We hypothesized that pregnancy increased UA distensibility and/or decreased myogenic tone. Given the fetal growth restriction and lower UA flow seen under chronic hypoxia, we further hypothesized that chronic hypoxia opposed these normal active and passive mechanical changes. UA were isolated from 12 nonpregnant and 12 pregnant (0.7 gestation) guinea pigs housed under normoxia or chronic hypoxia (3,960 m) and studied by pressure myography. Pregnancy increased UA diameter similarly under normoxia and hypoxia. Although chronic hypoxia raised resting tone in UA from nonpregnant guinea pigs to approximately 20% and tone was greater in preconstricted pregnant chronically hypoxic vs. normoxic UA (both P<0.01), there was an absence of myogenic response (i.e., an increase in tone with rising pressure) in all groups. Pregnancy increased UA distensibility 1.5-fold but did not change stiffness or the stress-strain relationship. Compared with vessels from normoxic pregnant animals, hypoxic pregnancy raised UA distensibility fourfold, decreased stiffness (rate constant b=3.80+/-1.06 vs. 8.92+/-1.25, respectively, P<0.01), lowered elastin by 50%, and shifted the stress-strain relationship upward such that four times as much strain was present at a given stress. We concluded that increased distensibility and low myogenic tone contribute to enlarging UA diameter and raising UA blood flow during pregnancy. Chronic hypoxia exaggerates the rise in distensibility and alters the stress-strain relationship in ways that may provoke vascular injury.

  19. Pressure-volume curves, static compliances and gas exchange in hyaline membrane disease during conventional mechanical and high-frequency ventilation.

    PubMed

    Pfenninger, J; Minder, C

    1988-01-01

    Eight premature infants with hyaline membrane disease needing artificial ventilation were studied at a mean age of 26.5 h. After a preparative phase they were randomly assigned either first to conventional mechanical ventilation (CMV; delivered by a Siemens Servo 900 C), followed by high-frequency ventilation (HFV; delivered by Percussionaire VDR 1 at 10 Hz) or vice versa, each period lasting 4 h. At the end of each period, arterial blood gases, lung volumes and alveolar pressures (Palv) during CMV or HFV and pressure-volume (P-V) curves of the total respiratory system were determined. Expiratory volumes were measured spirometrically, Palv by the clamping method, and the P-V curve was constructed by the syringe method. Single point static compliance at end-inspiration was higher during HFV (0.40 +/- 0.10 vs. 0.32 +/- 0.08 ml/cmH2O.kg-1; p = 0.02), whereas at end-expiration no difference was noted. Two points static compliances were also better during HFV than during CMV (0.32 +/- 0.08 vs. 0.24 +/- 0.06 ml/cmH2O.kg-1; p = 0.01). Static compliances derived from the steepest part of the inflation limb of the P-V curve were 0.55 +/- 0.12 after CMV and 0.50 +/- 0.12 ml/cmH2O.kg-1 after HFV (n.s.). Compared to CMV, HFV resulted in similar oxygenation and CO2-elimination at equal mean lung volumes, but at significantly lower mean Palv. It is concluded that recruitment of lung volume is achieved with less static recoil pressure by HFV. These findings are explained by differences in inspiration allowing more time for volume recruitment during HFV.

  20. [Mechanical ventilatory parameters guided by the low flow pressure-volume curve in patients with acute lung injury/acute respiratory distress syndrome].

    PubMed

    Tomicic, Vinko; Molina, Jorge; Graf, Jerónimo; Espinoza, Mauricio; Antúnez, Miguel; Errázuriz, Isabel; Aguilera, Pablo; Izquierdo, Francisco; López, Tania; Canals, Claudio

    2007-03-01

    Mechanical ventilation may contribute to lung injury and then enhance systemic inflammation. Optimal ventilatory parameters such as tidal volume (VT) and positive end expiratory pressure (PEEP) can be determined using different methods. Low flow pressure volume (P/V-LF) curve is a useful tool to assess the respiratory system mechanics and set ventilatory parameters. To set VT and PEEP according P/V-LF curve analysis and evaluate its effects on gas exchange and hemodynamic parameters. Twenty seven patients underwent P/V-LF within the first 72 hours of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). P/V-LF curves were obtained from the ventilator and both lower and upper inflexion points determined. Gas exchange and hemodynamic parameters were measured before and after modifying ventilator settings guided by P/V-LF curves. Ventilatory parameters set according P/V-LF curve, led to a rise of PEEP and reduction of VT: 11.6+/-2.8 to 14.1+/-2.1 cm H2O, and 9.7+/-2.4 to 8.8+/-2.2 mL/kg (p<0.01). Arterial to inspired oxygen fraction ratio increased from 158.0+/-66 to 188.5+/-68.5 (p<0.01), and oxygenation index was reduced, 13.7+/-8.2 to 12.3+/-7.2 (p<0.05). Cardiac output and oxygen delivery index (IDO2) were not modified. Demographic data, gas exchange improvement and respiratory system mechanics showed no significant difference between patients with extra-pulmonary and pulmonary ALI/ARDS. There was no evidence of significant adverse events related with this technique. P/V-LF curves information allowed us to adjust ventilatory parameters and optimize gas exchange without detrimental effects on oxygen delivery in mechanically ventilated ALI/ARDS patients.

  1. Arterial Stiffness.

    PubMed

    Avolio, Alberto

    2013-04-01

    Stiffness of large arteries has been long recognized as a significant determinant of pulse pressure. However, it is only in recent decades, with the accumulation of longitudinal data from large and varied epidemiological studies of morbidity and mortality associated with cardiovascular disease, that it has emerged as an independent predictor of cardiovascular risk. This has generated substantial interest in investigations related to intrinsic causative and associated factors responsible for the alteration of mechanical properties of the arterial wall, with the aim to uncover specific pathways that could be interrogated to prevent or reverse arterial stiffening. Much has been written on the haemodynamic relevance of arterial stiffness in terms of the quantification of pulsatile relationships of blood pressure and flow in conduit arteries. Indeed, much of this early work regarded blood vessels as passive elastic conduits, with the endothelial layer considered as an inactive lining of the lumen and as an interface to flowing blood. However, recent advances in molecular biology and increased technological sophistication for the detection of low concentrations of biochemical compounds have elucidated the highly important regulatory role of the endothelial cell affecting vascular function. These techniques have enabled research into the interaction of the underlying passive mechanical properties of the arterial wall with the active cellular and molecular processes that regulate the local environment of the load-bearing components. This review addresses these emerging concepts.

  2. Relationship of aortic valve calcification with coronary artery calcium severity: the Multi-Ethnic Study of Atherosclerosis (MESA).

    PubMed

    Nasir, Khurram; Katz, Ronit; Al-Mallah, Mouaz; Takasu, Junichiro; Shavelle, David M; Carr, Jeffery J; Kronmal, Richard; Blumenthal, Roger S; O'Brien, Kevin; Budoff, Matthew J

    2010-01-01

    Aortic valve calcification (AVC) and atherosclerosis share causative and pathologic features. We evaluated the relationship between AVC and coronary artery calcium (CAC) severity in the Multi-Ethnic Study of Atherosclerosis (MESA). Men and women aged 45-84 years (n=6809; mean age, 62 years) were studied. The presence and burden of AVC and CAC were determined by noncontrast cardiac computed tomography. Relative risk regression was used to model the probability of AVC as a function of CAC > 0 as well as CAC categories (0, 1-99, 100-399, and > or = 400) with the reference group being CAC=0. The prevalence of AVC and CAC was 13% and 50%, respectively. Among those without CAC, the prevalence of AVC was 5% and increased across levels of CAC severity such that 14%, 25%, and 38% had AVC with increasing CAC scores of 1-99, 100-399, and > or = 400, respectively (P for trend<0.0001). After controlling for patient demographic factors and cardiovascular risk factors, the prevalence ratio of AVC among those with mild CAC (1-99) was 1.83 (95% CI, 1.45-2.31) and increased to 3.36 (95% CI, 2.56-4.42) for CAC > or = 400. Similar statistically significant increased risk of AVC was found when CAC was assessed as a continuous variable. Our study shows that AVC is independently associated with increasing severity of CAC. 2010 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  3. Relationship between Angiotensin Converting Enzyme, Apelin, and New-Onset Atrial Fibrillation after Off-Pump Coronary Artery Bypass Grafting.

    PubMed

    Xu, Shu; Zhang, Jian; Xu, Yin-Li; Wu, Hai-Bo; Xue, Xiao-Dong; Wang, Hui-Shan

    2017-01-01

    It has been shown that inflammation and oxidative stress are important factors in postoperative atrial fibrillation (POAF). Angiotensin converting enzyme (ACE) and apelin have a close relationship with inflammation and oxidative stress. The effect of ACE and apelin on POAF after off-pump coronary artery bypass grafting (OPCABG) remains a question. The concentrations of serum ACE, angiotensin II (Ang II), apelin, bradykinin (BK), malondialdehyde (MDA), and C reactive protein (CRP) were measured in the perioperative period of OPCABG. The levels of serum ACE in the POAF group were higher than in the no POAF group both preoperatively and postoperatively. Apelin in the POAF group was lower than in the no POAF group. There was a correlation between serum ACE and apelin. Postoperatively, CRP and MDA in the POAF group were higher than in the no POAF group; however, there was no difference before the operation. Preoperative ACE and apelin were both significant and independent risk factors for POAF. In conclusion, the high ACE and low apelin preoperatively led to CRP and MDA being increased postoperatively, which was probably associated with POAF after OPCABG. Apelin may be a new predictor for POAF.

  4. Relationship between Angiotensin Converting Enzyme, Apelin, and New-Onset Atrial Fibrillation after Off-Pump Coronary Artery Bypass Grafting

    PubMed Central

    Xu, Shu; Zhang, Jian; Xu, Yin-li; Wu, Hai-bo; Xue, Xiao-dong

    2017-01-01

    It has been shown that inflammation and oxidative stress are important factors in postoperative atrial fibrillation (POAF). Angiotensin converting enzyme (ACE) and apelin have a close relationship with inflammation and oxidative stress. The effect of ACE and apelin on POAF after off-pump coronary artery bypass grafting (OPCABG) remains a question. The concentrations of serum ACE, angiotensin II (Ang II), apelin, bradykinin (BK), malondialdehyde (MDA), and C reactive protein (CRP) were measured in the perioperative period of OPCABG. The levels of serum ACE in the POAF group were higher than in the no POAF group both preoperatively and postoperatively. Apelin in the POAF group was lower than in the no POAF group. There was a correlation between serum ACE and apelin. Postoperatively, CRP and MDA in the POAF group were higher than in the no POAF group; however, there was no difference before the operation. Preoperative ACE and apelin were both significant and independent risk factors for POAF. In conclusion, the high ACE and low apelin preoperatively led to CRP and MDA being increased postoperatively, which was probably associated with POAF after OPCABG. Apelin may be a new predictor for POAF. PMID:28299332

  5. Quantitative relationship between global left ventricular thallium uptake and blood flow: effects of propranolol, ouabain, dipyridamole, and coronary artery occlusion

    SciTech Connect

    Melin, J.A.; Becker, L.C.

    1986-05-01

    The quantitative relationship between fractional myocardial thallium uptake and radioactive microsphere-determined flow was studied in 33 open chest dogs under baseline conditions during increased coronary flow (dipyridamole), decreased coronary flow (propranolol and coronary artery stenosis), inhibition of Na-K ATPase (ouabain), and regional infarction. Myocardial contents of thallium and microspheres were compared in left ventricular (LV) biopsies taken 5, 10, 15, 30, and 60 min after thallium injection, expressed as fractions of injected dose. Maximal LV thallium uptake occurred 10 min after injection and the 10-min values were therefore used for subsequent comparisons. Combining all dogs, fractional LV thallium content (% injected dose) correlated well with fractional LV blood flow (% cardiac output) (r = 0.95). However, for fractional LV flows in the low, normal, or moderately elevated range (LV flow/cardiac output less than 9%), thallium content consistently exceeded flow by about 15%. This relationship was not altered by ouabain or regional ischemia or infarction. For greatly elevated fractional LV flows (greater than 9%), thallium content was not significantly different from flow. To explain these differences, myocardial and systemic extraction fractions for thallium were determined in eight dogs with a dual tracer method. At baseline, myocardial extraction fraction was significantly greater than systemic (88 +/- 0.4% compared with 75 +/- 1%, p less than 0.001). During dipyridamole, myocardial extraction fraction decreased and myocardial and systemic values were no longer significantly different (82 +/- 1% compared with 79 +/- 1%). These results show that the fraction of injected thallium dose taken up by the LV myocardium exceeds the delivered fraction of cardiac output and is not altered by ouabain-induced inhibition or regional myocardial infarction.

  6. The relationship between regional brain volumes and the extent of coronary artery disease in mild cognitive impairment

    PubMed Central

    Barekatain, Majid; Askarpour, Hedyeh; Zahedian, Faezeh; Walterfang, Mark; Velakoulis, Dennis; Maracy, Mohammad Reza; Jazi, Mohammad Hashemi

    2014-01-01

    Background: There are conflicting reports regarding the association between coronary artery disease (CAD) and mild cognitive impairment (MCI). Volumetric Magnetic resonance imaging (MRI) investigations have been considered as an objective biomarker for MCI. In this study, we determined the relationship between the regional brain volumes and the extent of CAD in MCI patients and cognitively normal controls. Materials and Methods: In a case-control study a subset of MCI patients (n = 20) and cognitively normal controls (n = 20), aged 66.4 ± 4.6 and 65.3 ± 3.9 respectively, from subjects who were recently admitted to cardiac catheterization facilities in two general hospitals were selected. All subjects underwent a clinical interview, biochemical measures, neuropsychological testing and Neuropsychiatry Unit COGnitive assessment tool. Video records of coronary angiography were scored with the Gensini method. For volumetric evaluation of regions of interest, brain MRI scans was processed using the FreeSurfer software package the relationship between the regional brain volumes and the extent of CAD in MCI patients and cognitively normal controls were compared. Results: We have found that, there were significant differences between the two groups in volumes of left fusiform (P = 0.039), left pars triangularis (P = 0.003) and left superior temporal gyrus (P = 0.009), after controlling for intracranial volumes. Higher Gensini scores were associated with reduced volumes of total cortical volume (P = 0.047, R = −0.4), left precuneus (P = 0.022, R = −0.5), right inferior parietal lobule (P = 0.011, R = −0.5) and left supra marginal gyrus (P = 0.035, R = −0.04) in MCI. Conclusion: In MCI, a greater degree of coronary stenosis correlates with greater loss of gray matter in specific brain regions relevant to cognitive function. This, however, was not the case for cognitively normal subjects. PMID:25422659

  7. Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

    PubMed

    Boyer, Doug M; Kirk, E Christopher; Silcox, Mary T; Gunnell, Gregg F; Gilbert, Christopher C; Yapuncich, Gabriel S; Allen, Kari L; Welch, Emma; Bloch, Jonathan I; Gonzales, Lauren A; Kay, Richard F; Seiffert, Erik R

    2016-08-01

    Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic

  8. The Relationship between the Severity of Coronary Artery Disease and Epicardial Adipose Tissue Depends on The Left Ventricular Function

    PubMed Central

    Doesch, Christina; Süselbeck, Tim; Haghi, Dariusch; Streitner, Florian; Schoenberg, Stefan O.; Borggrefe, Martin; Papavassiliu, Theano

    2012-01-01

    Background Epicardial adipose tissue (EAT) is an active metabolic and endocrine organ. Previous studies focusing mainly on patients with preserved left ventricular function (LVF) could show a correlation between increased amounts of EAT and the extent and activity of coronary artery disease (CAD). However, to date, there are no data available about the relationship between EAT and the severity of CAD with respect to the whole spectrum of LVF impairment. Therefore, we evaluated this relationship in patients with CAD. Methods 250 patients with CAD and 50 healthy controls underwent CMR examination to assess EAT. The severity of CAD was defined using the angiographic Gensini score (GSS). Results The GSS ranged from 2–364. Linear regression analysis revealed a significant correlation between EAT and GSS (r = 0.177, p = 0.01). Patients with mild (GSS≤10) and moderate CAD (GSS>10−≤40) showed comparable EAT to healthy controls. However, in patients with severe CAD (GSS>40) EAT was significantly reduced (p<0.0001) compared to healthy controls. Interestingly, patients with the same GSS revealed different EAT depending on the left ventricular function (LVF). Patients with preserved LVF (LVF≥50%) showed more EAT mass compared to those with reduced LVF (LVF<50%) regardless of the GSS. In patients with preserved LVF and mild CAD, EAT was comparable to healthy controls (61.8±19.4 g vs. 62.9±14.4 g, p = 0.8). In patients with moderate CAD, EAT rose significantly to 83.1±24.9 g (p = 0.01) and started to decline to 66.4±23.6 g in patients with severe CAD (p = 0.03). Contrary, in CAD patients with reduced LVF, EAT was already significantly reduced in patients with mild CAD as compared to healthy controls (p = 0.001) and showed a stepwise decline with increasing CAD severity. Conclusion The relationship between EAT and the severity of CAD depends on LVF. These findings emphasize the multifactorial interaction between EAT and the severity of CAD

  9. Peripheral artery calcifications evaluated by histology correlate to those detected by CT: relationships with fetuin-A and FGF-23.

    PubMed

    Coen, Giorgio; De Paolis, Paolo; Ballanti, Paola; Pierantozzi, Andrea; Pisanò, Stefania; Sardella, Daniela; Mantella, Daniela; Pellegrino, Luigi; Silvestrini, Giuliana; Iappelli, Massimo; Di Giulio, Salvatore

    2011-01-01

    Calcification of arteries is a frequent occurrence in hemodialysis (HD) patients and is linked to mortality. This study was conducted to evaluate the correspondence between coronary calcification scores and calcifications observed histologically in peripheral arteries in HD patients. In addition the association of humoral parameters including fetuin-A and fibroblast growth factor 23 (FGF-23) with arterial calcifications was studied. HD patients (n=44) were studied with multislice computed tomography (CT) and histological quantification of arterial calcifications in the lower epigastric artery sampled at the time of renal transplant. In addition, humoral assays were performed including fetuin-A and FGF-23. There was a significant correlation between medial calcification of the artery and Agatston scores. Natural logarithm (Ln) FGF-23 significantly correlated to Ln Agatston score but not to Ln medial calcification. A significant negative correlation between fetuin-A and Ln FGF-23 was observed, changing to borderline significance after correction for age and Ln HD age. Ln Agatston score in a multiregression analysis was predicted by Ln FGF-23 and age. The association found between histologically evaluated calcification of the media of a peripheral artery in HD and the multislice CT Agatston scores is in favor of a generalized arterial calcification, either intimal or of tunica media, when calcium deposits are found in the coronary arteries. The association of FGF-23 with coronary calcification score, already reported, and less so with histological medial calcification is in favor of a link between the protein and intimal more than the medial calcification. FGF-23 may be considered a potential biomarker of arterial calcification in HD patients. The negative association between fetuin-A and FGF-23 may suggest a linkage between these humoral substances, vascular calcifications and mortality. The nature of this linkage requires further studies.

  10. Social relationships and longitudinal changes in body mass index and waist circumference: the coronary artery risk development in young adults study.

    PubMed

    Kershaw, Kiarri N; Hankinson, Arlene L; Liu, Kiang; Reis, Jared P; Lewis, Cora E; Loria, Catherine M; Carnethon, Mercedes R

    2014-03-01

    Few studies have examined longitudinal associations between close social relationships and weight change. Using data from 3,074 participants in the Coronary Artery Risk Development in Young Adults Study who were examined in 2000, 2005, and 2010 (at ages 33-45 years in 2000), we estimated separate logistic regression random-effects models to assess whether patterns of exposure to supportive and negative relationships were associated with 10% or greater increases in body mass index (BMI) (weight (kg)/height (m)(2)) and waist circumference. Linear regression random-effects modeling was used to examine associations of social relationships with mean changes in BMI and waist circumference. Participants with persistently high supportive relationships were significantly less likely to increase their BMI values and waist circumference by 10% or greater compared with those with persistently low supportive relationships after adjustment for sociodemographic characteristics, baseline BMI/waist circumference, depressive symptoms, and health behaviors. Persistently high negative relationships were associated with higher likelihood of 10% or greater increases in waist circumference (odds ratio = 1.62, 95% confidence interval: 1.15, 2.29) and marginally higher BMI increases (odds ratio = 1.50, 95% confidence interval: 1.00, 2.24) compared with participants with persistently low negative relationships. Increasingly negative relationships were associated with increases in waist circumference only. These findings suggest that supportive relationships may minimize weight gain, and that adverse relationships may contribute to weight gain, particularly via central fat accumulation.

  11. Relationship between site of myocardial infarction, left ventricular function and cytokine levels in patients undergoing coronary artery surgery.

    PubMed

    Kiris, Ilker; Kapan, Sahin; Narin, Cuneyt; Ozaydın, Mehmet; Cure, Medine Cumhur; Sutcu, Recep; Okutan, Huseyin

    The purpose of this study was to examine the relationship between left ventricular (LV) function, cytokine levels and site of myocardial infarction (MI) in patients undergoing coronary artery bypass grafting (CABG). Sixty patients undergoing CABG were divided into three groups (n = 20) according to their history of site of myocardial infarction (MI): no previous MI, anterior MI and posterior/inferior MI. In the pre-operative period, detailed analysis of LV function was done by transthoracic echocardiography. The levels of adrenomedullin, interleukin-1-beta, interleukin-6, tumour necrosis factor-alpha (TNF-α) and angiotensin-II in both peripheral blood samples and pericardial fluid were also measured. Echocardiographic analyses showed that the anterior MI group had significantly worse LV function than both the group with no previous MI and the posterior/inferior MI group (p < 0.05 for LV end-systolic diameter, fractional shortening, LV end-systolic volume, LV end-systolic volume index and ejection fraction). In the anterior MI group, both plasma and pericardial fluid levels of adrenomedullin and and pericardial fluid levels of interleukin-6 and interleukin- 1-beta were significantly higher than those in the group with no previous MI (p < 0.05), and pericardial fluid levels of adrenomedullin, interleukin-6 and interleukin-1-beta were significantly higher than those in the posterior/inferior MI group (p < 0.05). The results of this study indicate that (1) patients with an anterior MI had worse LV function than patients with no previous MI and those with a posterior/inferior MI, and (2) cytokine levels in the plasma and pericardial fluid in patients with anterior MI were increased compared to patients with no previous MI.

  12. Relationship between R-R interval and left ventricular systolic synchrony in subjects with coronary artery disease determined using angiography.

    PubMed

    Ma, Li; Li, Yanhong; Wu, Zhisheng; Mu, Yuming

    2016-01-01

    The aim of this study was to assess the relationship between R-R interval and left ventricular systolic synchrony in subjects with coronary artery disease determined using angiography. A total of 277 subjects who underwent coronary angiography for suspected CAD were recruited in this study. For all subjects, the R-R interval was quantified using simultaneous ECG, and the times to peak systolic longitudinal strain (Tssl) on 17 LV segments were quantified using four-dimensional (4D) speckle tracking echocardiography (STE) and manually measured. The independent predictors of R-R interval using multiple linear regression analyses were the time to peak systolic longitudinal strain in the apical-septal segment (Tssl-Apical-S) (β=0.325, P=0.000), smoking status (β=0.141, P=0.013), and the time to peak systolic longitudinal strain in the basal-anterolateral segment (Tssl-Basal-AL) (β=0.151, P=0.014), which were significantly independently associated with the R-R interval. In multiple regression analyses, smoking status (OR, 1.943; 95% CI, 1.119-3.375, P=0.018), Tssl-Basal-AL (OR, 1.002; 95% CI, 1.000-1.004, P=0.043), the time to peak systolic longitudinal strain in the mid-inferoseptal segment (Tssl-Mid-IS) (OR, 1.008; 95% CI, 1.003-1.013, P=0.004), and Tssl-Apical-S (OR, 1.010; 95% CI, 1.004-1.016, P=0.002) remained independently associated with the risk of a longer R-R interval (the median 849.49 ms was set as the cutoff value) in the population. Our findings may provide the basis for future investigations of LV systolic synchrony and cardiac resynchronization therapy.

  13. Relationship between site of myocardial infarction, left ventricular function and cytokine levels in patients undergoing coronary artery surgery

    PubMed Central

    Ilker, Kiris; Sahin, Kapan; Huseyin, Okutan,; Cuneyt, Narin; Mehmet, Ozaydın; Medine, Cumhur Cure; Recep, Sutcu

    2016-01-01

    Summary Background The purpose of this study was to examine the relationship between left ventricular (LV) function, cytokine levels and site of myocardial infarction (MI) in patients undergoing coronary artery bypass grafting (CABG). Methods Sixty patients undergoing CABG were divided into three groups (n = 20) according to their history of site of myocardial infarction (MI): no previous MI, anterior MI and posterior/inferior MI. In the pre-operative period, detailed analysis of LV function was done by transthoracic echocardiography.The levels of adrenomedullin, interleukin-1-beta,interleukin-6, tumour necrosis factor-alpha (TNF-α) and angiotensin-II in both peripheral blood samples and pericardial fluid were also measured. Results Echocardiographic analyses showed that the anterior MI group had significantly worse LV function than both the group with no previous MI and the posterior/inferior MI group (p < 0.05 for LV end-systolic diameter, fractional shortening, LV end-systolic volume, LV end-systolic volume index and ejection fraction). In the anterior MI group, both plasma and pericardial fluid levels of adrenomedullin and and pericardial fluid levels of interleukin-6 and interleukin- 1-beta were significantly higher than those in the group with no previous MI (p < 0.05), and pericardial fluid levels of adrenomedullin, interleukin-6 and interleukin-1-beta were significantly higher than those in the posterior/inferior MI group (p < 0.05). Conclusions The results of this study indicate that (1) patients with an anterior MI had worse LV function than patients with no previous MI and those with a posterior/inferior MI, and (2) cytokine levels in the plasma and pericardial fluid in patients with anterior MI were increased compared to patients with no previous MI. PMID:27805242

  14. The relationship between serum hypoxia-inducible factor 1α and coronary artery calcification in asymptomatic type 2 diabetic patients

    PubMed Central

    2014-01-01

    Background Hypoxia-inducible factor 1 (HIF-1), a master regulator of oxygen homeostasis, is a heterodimer consisting of HIF-1α and HIF-1β subunits, and is implicated in calcification of cartilage and vasculature. The goal of this study was to determine the relationship between serum HIF-1α with coronary artery calcification (CAC) in patients with type 2 diabetes. Methods The subjects were 405 (262 males, 143 females, age 51.3 ± 6.4 years) asymptomatic patients with type 2 diabetes mellitus. Serum HIF-1α and interleukin-6 (IL-6) levels were measured by ELISA. CAC scores were assessed by a 320-slice CT scanner. The subjects were divided into 4 quartiles depending on serum HIF-1α levels. Results Average serum HIF-1α was 184.4 ± 66.7 pg/ml. Among patients with higher CAC scores, HIF-1α levels were also significantly increased (p <0.001). HIF-1α levels positively correlated with CRP, IL-6, UKPDS risk score, HbA1c, FBG, and CACS, but did not correlate with diabetes duration, age, and LDL. According to the multivariate analysis, HIF-1α levels significantly and independently predict the presence of CAC. ROC curve analysis showed that the serum HIF-1α level can predict the extent of CAC, but the specificity was lower than the traditional risk factors UKPDS and HbA1c. Conclusion As a marker of hypoxia, serum HIF-1α level may be an independent risk factor for the presence of CAC. These findings indicate that elevated serum HIF-1α may be involved in vascular calcification in patients with type 2 diabetes mellitus. PMID:24564828

  15. Relationship between R-R interval and left ventricular systolic synchrony in subjects with coronary artery disease determined using angiography

    PubMed Central

    Ma, Li; Li, Yanhong; Wu, Zhisheng; Mu, Yuming

    2016-01-01

    The aim of this study was to assess the relationship between R-R interval and left ventricular systolic synchrony in subjects with coronary artery disease determined using angiography. A total of 277 subjects who underwent coronary angiography for suspected CAD were recruited in this study. For all subjects, the R-R interval was quantified using simultaneous ECG, and the times to peak systolic longitudinal strain (Tssl) on 17 LV segments were quantified using four-dimensional (4D) speckle tracking echocardiography (STE) and manually measured. The independent predictors of R-R interval using multiple linear regression analyses were the time to peak systolic longitudinal strain in the apical-septal segment (Tssl-Apical-S) (β=0.325, P=0.000), smoking status (β=0.141, P=0.013), and the time to peak systolic longitudinal strain in the basal-anterolateral segment (Tssl-Basal-AL) (β=0.151, P=0.014), which were significantly independently associated with the R-R interval. In multiple regression analyses, smoking status (OR, 1.943; 95% CI, 1.119-3.375, P=0.018), Tssl-Basal-AL (OR, 1.002; 95% CI, 1.000-1.004, P=0.043), the time to peak systolic longitudinal strain in the mid-inferoseptal segment (Tssl-Mid-IS) (OR, 1.008; 95% CI, 1.003-1.013, P=0.004), and Tssl-Apical-S (OR, 1.010; 95% CI, 1.004-1.016, P=0.002) remained independently associated with the risk of a longer R-R interval (the median 849.49 ms was set as the cutoff value) in the population. Our findings may provide the basis for future investigations of LV systolic synchrony and cardiac resynchronization therapy. PMID:28078178

  16. Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function

    PubMed Central

    Yotti, Raquel; del Villar, Candelas Pérez; del Álamo, Juan C.; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Carlos Antoranz, J.; Mar Desco, M.; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

    2013-01-01

    In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart. PMID:23743396

  17. Diastolic chamber properties of the left ventricle assessed by global fitting of pressure-volume data: improving the gold standard of diastolic function.

    PubMed

    Bermejo, Javier; Yotti, Raquel; Pérez del Villar, Candelas; del Álamo, Juan C; Rodríguez-Pérez, Daniel; Martínez-Legazpi, Pablo; Benito, Yolanda; Antoranz, J Carlos; Desco, M Mar; González-Mansilla, Ana; Barrio, Alicia; Elízaga, Jaime; Fernández-Avilés, Francisco

    2013-08-15

    In cardiovascular research, relaxation and stiffness are calculated from pressure-volume (PV) curves by separately fitting the data during the isovolumic and end-diastolic phases (end-diastolic PV relationship), respectively. This method is limited because it assumes uncoupled active and passive properties during these phases, it penalizes statistical power, and it cannot account for elastic restoring forces. We aimed to improve this analysis by implementing a method based on global optimization of all PV diastolic data. In 1,000 Monte Carlo experiments, the optimization algorithm recovered entered parameters of diastolic properties below and above the equilibrium volume (intraclass correlation coefficients = 0.99). Inotropic modulation experiments in 26 pigs modified passive pressure generated by restoring forces due to changes in the operative and/or equilibrium volumes. Volume overload and coronary microembolization caused incomplete relaxation at end diastole (active pressure > 0.5 mmHg), rendering the end-diastolic PV relationship method ill-posed. In 28 patients undergoing PV cardiac catheterization, the new algorithm reduced the confidence intervals of stiffness parameters by one-fifth. The Jacobian matrix allowed visualizing the contribution of each property to instantaneous diastolic pressure on a per-patient basis. The algorithm allowed estimating stiffness from single-beat PV data (derivative of left ventricular pressure with respect to volume at end-diastolic volume intraclass correlation coefficient = 0.65, error = 0.07 ± 0.24 mmHg/ml). Thus, in clinical and preclinical research, global optimization algorithms provide the most complete, accurate, and reproducible assessment of global left ventricular diastolic chamber properties from PV data. Using global optimization, we were able to fully uncouple relaxation and passive PV curves for the first time in the intact heart.

  18. Coronary Artery Axial Plaque Stress and its Relationship With Lesion Geometry: Application of Computational Fluid Dynamics to Coronary CT Angiography.

    PubMed

    Choi, Gilwoo; Lee, Joo Myung; Kim, Hyun-Jin; Park, Jun-Bean; Sankaran, Sethuraman; Otake, Hiromasa; Doh, Joon-Hyung; Nam, Chang-Wook; Shin, Eun-Seok; Taylor, Charles A; Koo, Bon-Kwon

    2015-10-01

    The purpose of this study was to characterize the hemodynamic force acting on plaque and to investigate its relationship with lesion geometry. Coronary plaque rupture occurs when plaque stress exceeds plaque strength. Computational fluid dynamics was applied to 114 lesions (81 patients) from coronary computed tomography angiography. The axial plaque stress (APS) was computed by extracting the axial component of hemodynamic stress acting on stenotic lesions, and the axial lesion asymmetry was assessed by the luminal radius change over length (radius gradient [RG]). Lesions were divided into upstream-dominant (upstream RG > downstream RG) and downstream-dominant lesions (upstream RG < downstream RG) according to the RG. Thirty-three lesions (28.9%) showed net retrograde axial plaque force. Upstream APS linearly increased as lesion severity increased, whereas downstream APS exhibited a concave function for lesion severity. There was a negative correlation (r = -0.274, p = 0.003) between APS and lesion length. The pressure gradient, computed tomography-derived fractional flow reserve (FFRCT), and wall shear stress were consistently higher in upstream segments, regardless of the lesion asymmetry. However, APS was higher in the upstream segment of upstream-dominant lesions (11,371.96 ± 5,575.14 dyne/cm(2) vs. 6,878.14 ± 4,319.51 dyne/cm(2), p < 0.001), and in the downstream segment of downstream-dominant lesions (7,681.12 ± 4,556.99 dyne/cm(2) vs. 11,990.55 ± 5,556.64 dyne/cm(2), p < 0.001). Although there were no differences in FFRCT, % diameter stenosis, and wall shear stress pattern, the distribution of APS was different between upstream- and downstream-dominant lesions. APS uniquely characterizes the stenotic segment and has a strong relationship with lesion geometry. Clinical application of these hemodynamic and geometric indices may be helpful to assess the future risk of plaque rupture and to determine treatment strategy for patients with coronary artery

  19. Relationship between abdominal aortic and coronary artery calcification as detected by computed tomography in chronic kidney disease patients.

    PubMed

    Takayama, Yohei; Yasuda, Yoshinari; Suzuki, Susumu; Shibata, Yohei; Tatami, Yosuke; Shibata, Kanako; Niwa, Misao; Sawai, Akihiro; Morimoto, Ryota; Kato, Sawako; Ishii, Hideki; Maruyama, Shoichi; Murohara, Toyoaki

    2016-07-01

    The purpose of this study was to investigate the relationship between abdominal aortic calcification (AAC) and coronary artery calcification (CAC) in chronic kidney disease (CKD) patients. We evaluated 126 asymptomatic CKD patients (mean estimated glomerular filtration rate: 36.1 ± 14.1 mL/min/1.73 m(2), mean age 70.3 ± 10.1 years). A non-contrast computed tomography scan was used to determine the abdominal aortic calcification index (ACI) and CAC score, and this relationship was investigated. Among the subjects, AAC was present in 109 patients (86.5 %) as defined by ACI >0 and median ACI was 11.7 %. ACI increased in accordance with advances in CAC score grades (3.0, 5.2, 17.2, and 32.8 % for CAC score 0, 1-100, 101-400, and 401 or more, respectively, p < 0.001). Even after multivariate adjustment, ACI was independently associated with severe CAC score as defined by CAC score >400 [odds ratio 1.08, 95 % confidence interval (CI) 1.04-1.12, p < 0.001]. Receiver-operating curve analysis showed that the ACI optimal cut-off value predicting severe CAC score was 16.5 % (area under the curve = 0.79, 95 % CI 0.69-0.90, p < 0.001). The C statics for predicting CAC score was significantly increased by adding ACI values to the model including other risk factors (0.853 versus 0.737, p = 0.023). In conclusion, the ACI value of 16.5 % allows us to predict the presence of severe CAC in CKD patients, and that the addition of ACI to the model with traditional risk factors significantly improves the predictive ability of severe CAC score. These data reinforce the utility of ACI as a screening tool in clinical practice.

  20. Relationship between epicardial ST-segment elevation and myocardial ischemic damage after experimental coronary artery occlusion in dogs.

    PubMed Central

    Heng, M K; Singh, B N; Norris, R M; John, M B; Elliot, R

    1976-01-01

    The relationship between early and late epicardial electrocardiographic changes as well as those in regional myocardial blood flow (MBF) and the severity of myocardial damage was determined in 12 anesthetized dogs with left anterior descending coronary artery ligation. Radioactive microspheres (15 mum) were used to measure regional MBF at 15 min (early) and 24 h (late) after coronary occlusion. Severity of myocardial damage was assessed by the extent of myocardial creatine phosphokinase depletion 24 h after coronary ligation. There was a close linear correlation between myocardial creatine phosphokinase activity and regional MBF both early (r=0.93, 2P less than 0.001) and late (r=0.88, 2P less than 0.001). An inverse but less precise relationship existed between acute epicardial ST-segment elevation and early (r=-0.41, 2P less than 0.001), or late (r=0.35, 2P less than 0.05) regional MBF. Similarly, a weak correlation was found between myocardial creatine phosphokinase (IU/mg protein) at 24 h and early epicardial ST (millivolt) elevation (r=-0.36, 2P less than 0.02). In the center zones of the infarct with MBF 1/10 of normal, about 35% of the areas with normal QRS width had no epicardial ST-segment elevation 15 min after coronary occlusion. About 44% of the areas which developed pathological Q-waves in the electrocardiogram at 24 h had no ST elevation 15 min after coronary ligation. Late evolution of abnormal Q-waves occurred almost invariably in areas in which the early MBF was reduced to less than 50% of normal and in areas which subsequently had myocardial creatine phosphokinase levels reduced to less than 60% of normal. After coronary occlusion, the severity of the ultimate myocardial damage, which was directly proportional to the degree of reduction in MBF, was therefore not reliably predicted by the early epicardial ST-segment elevation. The data obtained in these studies suggest the need for caution in the use of acute ST-segment elevation as a predictive

  1. A self-calibrating telemetry system for measurement of ventricular pressure-volume relations in conscious, freely moving rats.

    PubMed

    Uemura, Kazunori; Kawada, Toru; Sugimachi, Masaru; Zheng, Can; Kashihara, Koji; Sato, Takayuki; Sunagawa, Kenji

    2004-12-01

    Using Bluetooth wireless technology, we developed an implantable telemetry system for measurement of the left ventricular pressure-volume relation in conscious, freely moving rats. The telemetry system consisted of a pressure-conductance catheter (1.8-Fr) connected to a small (14-g) fully implantable signal transmitter. To make the system fully telemetric, calibrations such as blood resistivity and parallel conductance were also conducted telemetrically. To estimate blood resistivity, we used four electrodes arranged 0.2 mm apart on the pressure-conductance catheter. To estimate parallel conductance, we used a dual-frequency method. We examined the accuracy of calibrations, stroke volume (SV) measurements, and the reproducibility of the telemetry. The blood resistivity estimated telemetrically agreed with that measured using an ex vivo cuvette method (y=1.09x - 11.9, r2= 0.88, n=10). Parallel conductance estimated by the dual-frequency (2 and 20 kHz) method correlated well with that measured by a conventional saline injection method (y=1.59x - 1.77, r2= 0.87, n=13). The telemetric SV closely correlated with the flowmetric SV during inferior vena cava occlusions (y=0.96x + 7.5, r2=0.96, n=4). In six conscious rats, differences between the repeated telemetries on different days (3 days apart on average) were reasonably small: 13% for end-diastolic volume, 20% for end-systolic volume, 28% for end-diastolic pressure, and 6% for end-systolic pressure. We conclude that the developed telemetry system enables us to estimate the pressure-volume relation with reasonable accuracy and reproducibility in conscious, untethered rats.

  2. The correlation between pulsatile intracranial pressure and indices of intracranial pressure-volume reserve capacity: results from ventricular infusion testing.

    PubMed

    Eide, Per Kristian

    2016-12-01

    OBJECTIVE The objective of this study was to examine how pulsatile and static intracranial pressure (ICP) scores correlate with indices of intracranial pressure-volume reserve capacity, i.e., intracranial elastance (ICE) and intracranial compliance (ICC), as determined during ventricular infusion testing. METHODS All patients undergoing ventricular infusion testing and overnight ICP monitoring during the 6-year period from 2007 to 2012 were included in the study. Clinical data were retrieved from a quality registry, and the ventricular infusion pressure data and ICP scores were retrieved from a pressure database. The ICE and ICC (= 1/ICE) were computed during the infusion phase of the infusion test. RESULTS During the period from 2007 to 2012, 82 patients with possible treatment-dependent hydrocephalus underwent ventricular infusion testing within the department of neurosurgery. The infusion tests revealed a highly significant positive correlation between ICE and the pulsatile ICP scores mean wave amplitude (MWA) and rise-time coefficient (RTC), and the static ICP score mean ICP. The ICE was negatively associated with linear measures of ventricular size. The overnight ICP recordings revealed significantly increased MWA (> 4 mm Hg) and RTC (> 20 mm Hg/sec) values in patients with impaired ICC (< 0.5 ml/mm Hg). CONCLUSIONS In this study cohort, there was a significant positive correlation between pulsatile ICP and ICE measured during ventricular infusion testing. In patients with impaired ICC during infusion testing (ICC < 0.5 ml/mm Hg), overnight ICP recordings showed increased pulsatile ICP (MWA > 4 mm Hg, RTC > 20 mm Hg/sec), but not increased mean ICP (< 10-15 mm Hg). The present data support the assumption that pulsatile ICP (MWA and RTC) may serve as substitute markers of pressure-volume reserve capacity, i.e., ICE and ICC.

  3. AV interval optimization using pressure volume loops in dual chamber pacemaker patients with maintained systolic left ventricular function.

    PubMed

    Eberhardt, Frank; Hanke, Thorsten; Fitschen, Joern; Heringlake, Matthias; Bode, Frank; Schunkert, Heribert; Wiegand, Uwe K H

    2012-08-01

    Atrioventricular (AV) interval optimization is often deemed too time-consuming in dual-chamber pacemaker patients with maintained LV function. Thus the majority of patients are left at their default AV interval. To quantify the magnitude of hemodynamic improvement following AV interval optimization in chronically paced dual chamber pacemaker patients. A pressure volume catheter was placed in the left ventricle of 19 patients with chronic dual chamber pacing and an ejection fraction >45 % undergoing elective coronary angiography. AV interval was varied in 10 ms steps from 80 to 300 ms, and pressure volume loops were recorded during breath hold. The average optimal AV interval was 152 ± 39 ms compared to 155 ± 8 ms for the average default AV interval (range 100-240 ms). The average improvement in stroke work following AV interval optimization was 935 ± 760 mmHg/ml (range 0-2,908; p < 0.001), which translates into an average improvement of 14 ± 9 % (range 0-28). A 10 ms variation of the AV interval changes the average stroke work by 207 ± 162 mmHg/ml. AV interval optimization also leads to improved systolic dyssynchrony indices (17.7 ± 7.0 vs. 19.4 ± 7.1 %; p = 0.01). The overall hemodynamic effect of AV interval optimization in patients with maintained LV function is in the same range as for patients undergoing cardiac resynchronization therapy for several parameters. The positive effect of AV interval optimization also applies to patients who have been chronically paced for years.

  4. Experimental Study of Anisotropic Stress/Strain Relationships of Aortic and Pulmonary Artery Homografts and Synthetic Vascular Grafts.

    PubMed

    Jia, Yueqian; Qiao, Yangyang; Ricardo Argueta-Morales, I; Maung, Aung; Norfleet, Jack; Bai, Yuanli; Divo, Eduardo; Kassab, Alain J; DeCampli, William M

    2017-10-01

    Homografts and synthetic grafts are used in surgery for congenital heart disease (CHD). Determining these materials' mechanical properties will aid in understanding tissue behavior when subjected to abnormal CHD hemodynamics. Homograft tissue samples from anterior/posterior aspects, of ascending/descending aorta (AA, DA), innominate artery (IA), left subclavian artery (LScA), left common carotid artery (LCCA), main/left/right pulmonary artery (MPA, LPA, RPA), and synthetic vascular grafts, were obtained in three orientations: circumferential, diagonal (45 deg relative to circumferential direction), and longitudinal. Samples were subjected to uniaxial tensile testing (UTT). True strain-Cauchy stress curves were individually fitted for each orientation to calibrate Fung model. Then, they were used to calibrate anisotropic Holzapfel-Gasser model (R2 > 0.95). Most samples demonstrated a nonlinear hyperelastic strain-stress response to UTT. Stiffness (measured by tangent modulus at different strains) in all orientations were compared and shown as contour plots. For each vessel segment at all strain levels, stiffness was not significantly different among aspects and orientations. For synthetic grafts, stiffness was significantly different among orientations (p < 0.042). Aorta is significantly stiffer than pulmonary artery at 10% strain, comparing all orientations, aspects, and regions (p = 0.0001). Synthetic grafts are significantly stiffer than aortic and pulmonary homografts at all strain levels (p < 0.046). Aortic, pulmonary artery, and synthetic grafts exhibit hyperelastic biomechanical behavior with anisotropic effect. Differences in mechanical properties among vascular grafts may affect native tissue behavior and ventricular/arterial mechanical coupling, and increase the risk of deformation due to abnormal CHD hemodynamics.

  5. The relationship between mean arterial pressure and decreased glomerular filtration rate in rural areas of Northeast China.

    PubMed

    Yang, Hongmei; Guo, Xiaofan; Zhang, Xingang; Li, Zhao; Yu, Shasha; Zheng, Liqiang; Li, Wenna; Zhou, Ying; Sun, Yingxian

    2015-08-13

    Low mean arterial pressure (MAP) can cause low renal blood flow and damage the kidneys. However, in the general population, it remains unclear whether or not decline in renal function is related to MAP. The present study examined the relationship between MAP and decreased glomerular filtration rate(GFR) in participants aged ≥ 35 years from the Liaoning province of China. A total of 11345 representative individuals aged ≥ 5 years was selected and a cross-sectional survey was conducted from January 2012 to August 2013 to describe the gender-specific prevalence and factors associated with decreased GFR in rural areas of Liaoning Province. Men with decreased eGFR (eGFR < 60 ml/min per 1.73 m(2)) were older, and had higher meanWC, systolic and diastolic BP, PP, MAP, total fasting glucose, LDL-C ,glyceride and uric acid levels and were current drinker/smoker at the baseline (all P < 0.05). Those with low education level, low income, low physical activity, low hemoglobin and HDL-C level had decreased eGFR (all P < 0.05). In women, the results were similar to those of men, but DBP and drinking status had no associations with the eGFR at the baseline (all P < 0.05). After adjustment for age, men with MAP of > 112.2 mmHg versus ≤ 93.8 mmHg had ORs for decreased eGFR of 2.367 (95 % CI: 1.248 to 4.488) .After multivariable adjustment, an MAP of > 112.2 mmHg versus ≤ 93.8 mmHg had an OR for decreased eGFR of 3.249 (95 % CI:1.394 to 7.575) in men, whereas in women, MAP was not associated with decreased eGFR. MAP was associated with decreased eGFR in men, while in women MAP was not associated with decreased eGFR. These findings provide some evidence that a different adaptive response to renal regulation may exist in males and females.

  6. The relationship between calcium kidney stones, arterial stiffness and bone density: unraveling the stone-bone-vessel liaison.

    PubMed

    Fabris, Antonia; Ferraro, Pietro Manuel; Comellato, Gabriele; Caletti, Chiara; Fantin, Francesco; Zaza, Gianluigi; Zamboni, Mauro; Lupo, Antonio; Gambaro, Giovanni

    2015-10-01

    Kidney stone disease is associated with a higher incidence of cardio-vascular (CV) events for still unclear reasons. Reduced bone density is also a frequent finding in calcium kidney stones. The association of reduced bone density with increased vascular stiffness and calcification has been discovered in a number of conditions. We investigated the hypothesis that patients with calcium kidney stones have increased arterial stiffness, which would be associated with reduced bone density and higher CV risk. We compared measures of arterial stiffness [carotid-radial pulse-wave velocity (CR-PWV), carotid-femoral pulse-wave velocity (CF-PWV) and augmentation index (AI)] and of bone density (T-scores determined at lumbar spine, neck and hip) among 42 idiopathic calcium stone formers compared with 42 age- and sex-matched healthy volunteers. Stone formers had higher values of CR-PWV, CF-PWV and AI, and lower values of all T-scores. Furthermore, the prevalence of abnormal arterial stiffness and reduced bone density was significantly higher among stone formers. Statistical adjustment for age, sex, body mass index and other covariates did not change the results. Our study confirms that stone formers have increased arterial stiffness and reduced bone density. Abnormal arterial stiffness appears to be independent of reduced bone density and may explain the higher CV risk observed in stone formers.

  7. Relationships between HDL-C, hs-CRP, with Central Arterial Stiffness in Apparently Healthy People Undergoing a General Health Examination

    PubMed Central

    Fan, Li; Ye, Ping; Yuan, Ying; Lu, XueChun; Wang, Fan; Zeng, Qiang

    2013-01-01

    Background Some cardiovascular risk factors have been confirmed to be positively correlated with arterial stiffness. However, it is unclear whether HDL-C, a well-established anti-risk factor, has an independent association with arterial stiffness. The aim of this study was to evaluate the relationship between HDL-C levels and arterial stiffness and the possible role of high-sensitivity C-reactive protein (hs-CRP) in this potential correlation in apparently healthy adults undergoing a general health examination in China. Materials and Methods This was a cross-sectional survey. In total, 15,302 participants (age range, 18–82 years; mean, 43.88±8.44 years) were recruited during routine health status examinations. A questionnaire was used and we measured the body mass index, systolic and diastolic blood pressure, and fasting glucose, and serum lipid, uric acid, hs-CRP, and serum creatinine levels of each participant. Central arterial stiffness was assessed by carotid–femoral pulse wave velocity (cf-PWV). Results HDL-C levels decreased as cf-PWV increased. Pearson’s correlation analysis revealed that HDL-C levels were associated with cf-PWV (r=−0.18, P<0.001). hs-CRP levels were positively associated with cf-PWV (r=0.13). After adjustment for all confounders, HDL-C was inversely independently associated with all quartiles of cf-PWV. Furthermore, HDL-C was associated with cf-PWV in different quartiles of hs-CRP, and the correlation coefficients (r) gradually decreased with increasing hs-CRP levels (quartiles 1–4). Conclusions HDL-C is inversely independently associated with central arterial stiffness. The anti-inflammatory activity of HDL-C may mediate its relationship with cf-PWV. Further, long-term follow-up studies are needed to evaluate whether high HDL-C levels are protective against central artery stiffening through the anti-inflammatory activity of HDL-C. PMID:24312587

  8. Coronary Arteries

    MedlinePlus

    ... and animations for grades K-6. The Coronary Arteries Coronary Circulation The heart muscle, like every other ... into two main coronary blood vessels (also called arteries). These coronary arteries branch off into smaller arteries, ...

  9. Angus sattle at high altitude: Genetic relationships and initial genome-wide association analyses of pulmonary arterial pressure

    USDA-ARS?s Scientific Manuscript database

    Records from yearling Angus (n = 10,647) cattle from elevation 2,340 m were used in genetic analysis of pulmonary arterial pressure (PAP). Bulls were developed within a grain-supplemented performance test, whereas heifers and steers were grazed. The BovineSNP50 Beadchip was used to genotype a subset...

  10. Relationship between heart rate variability, blood pressure and arterial wall properties during air and oxygen breathing in healthy subjects.

    PubMed

    Graff, Beata; Szyndler, Anna; Czechowicz, Krzysztof; Kucharska, Wiesława; Graff, Grzegorz; Boutouyrie, Pierre; Laurent, Stephane; Narkiewicz, Krzysztof

    2013-11-01

    Previous studies reported that normobaric hyperoxia influences heart rate, arterial pressure, cardiac output and systemic vascular resistance, but the mechanisms underlying these changes are still not fully understood. Several factors are considered including degeneration of endothelium-derived nitric oxide by reactive oxygen species, the impact of oxygen-free radicals on tissues and alterations of autonomic nervous system function. Recently, new devices for the detailed non-invasive assessment of large and small arteries have been developed. Therefore, the aim of our study was to assess heart rate variability (HRV) as a potential indicator of autonomic balance and its relation to blood pressure and vascular properties during medical air (MAB) and 100% oxygen breathing (OXB) in healthy volunteers. In 12 healthy subjects we assessed heart rate and blood pressure variability, baroreflex sensitivity, respiratory frequency, common carotid artery diameter and its wall distensibility, as well as changes in the digital artery pulse waveform, stroke index and systemic vascular resistance during MAB and OXB. Mean and systolic blood pressure have increased significantly while digital pulse amplitude and carotid artery diameter were significantly lower during hyperoxia. Heart rate variability measures did not differ during MAB and OXB. However, the correlations between spectral HRV components and those hemodynamic parameters which have changed due to hyperoxia varied substantially during MAB (correlated significantly) and OXB (no significant correlations were noted). Our findings suggest that autonomic nervous system might not be the main mediator of the cardiovascular changes during 100% oxygen breathing in healthy subjects. It seems that the direct vascular responses are initial consequences of hyperoxia and other cardiovascular parameter alterations are secondary to them. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. End-systolic Pressure-Volume Relation, Ejection Fraction, and Heart Failure: Theoretical Aspect and Clinical Applications.

    PubMed

    Shoucri, Rachad M

    2015-01-01

    A mathematical formalism describing the nonlinear end-systolic pressure-volume relation (ESPVR) is used to derive new indexes that can be used to assess the performance of the heart left ventricle by using the areas under the ESPVR (units of energy), the ordinates of the ESPVR (units of pressure), or from slopes of the curvilinear ESPVR. New relations between the ejection fraction (EF) and the parameters describing the ESPVR give some insight into the problem of heart failure (HF) with normal or preserved ejection fraction. Relations between percentage occurrence of HF and indexes derived from the ESPVR are also discussed. When ratios of pressures are used, calculation can be done in a noninvasive way with the possibility of interesting applications in routine clinical work. Applications to five groups of clinical data are given and discussed (normal group, aortic stenosis, aortic valvular regurgitation, mitral valvular regurgitation, miscellaneous cardiomyopathies). No one index allows a perfect segregation between all clinical groups, it is shown that appropriate use of two indexes (bivariate analysis) can lead to better separation of different clinical groups.

  12. Strain and strain rate by speckle-tracking echocardiography correlate with pressure-volume loop-derived contractility indices in a rat model of athlete's heart.

    PubMed

    Kovács, Attila; Oláh, Attila; Lux, Árpád; Mátyás, Csaba; Németh, Balázs Tamás; Kellermayer, Dalma; Ruppert, Mihály; Török, Marianna; Szabó, Lilla; Meltzer, Anna; Assabiny, Alexandra; Birtalan, Ede; Merkely, Béla; Radovits, Tamás

    2015-04-01

    Contractile function is considered to be precisely measurable only by invasive hemodynamics. We aimed to correlate strain values measured by speckle-tracking echocardiography (STE) with sensitive contractility parameters of pressure-volume (P-V) analysis in a rat model of exercise-induced left ventricular (LV) hypertrophy. LV hypertrophy was induced in rats by swim training and was compared with untrained controls. Echocardiography was performed using a 13-MHz linear transducer to obtain LV long- and short-axis recordings for STE analysis (GE EchoPAC). Global longitudinal (GLS) and circumferential strain (GCS) and longitudinal (LSr) and circumferential systolic strain rate (CSr) were measured. LV P-V analysis was performed using a pressure-conductance microcatheter, and load-independent contractility indices [slope of the end-systolic P-V relationship (ESPVR), preload recruitable stroke work (PRSW), and maximal dP/dt-end-diastolic volume relationship (dP/dtmax-EDV)] were calculated. Trained rats had increased LV mass index (trained vs. control; 2.76 ± 0.07 vs. 2.14 ± 0.05 g/kg, P < 0.001). P-V loop-derived contractility parameters were significantly improved in the trained group (ESPVR: 3.58 ± 0.22 vs. 2.51 ± 0.11 mmHg/μl; PRSW: 131 ± 4 vs. 104 ± 2 mmHg, P < 0.01). Strain and strain rate parameters were also supernormal in trained rats (GLS: -18.8 ± 0.3 vs. -15.8 ± 0.4%; LSr: -5.0 ± 0.2 vs. -4.1 ± 0.1 Hz; GCS: -18.9 ± 0.8 vs. -14.9 ± 0.6%; CSr: -4.9 ± 0.2 vs. -3.8 ± 0.2 Hz, P < 0.01). ESPVR correlated with GLS (r = -0.71) and LSr (r = -0.53) and robustly with GCS (r = -0.83) and CSr (r = -0.75, all P < 0.05). PRSW was strongly related to GLS (r = -0.64) and LSr (r = -0.71, both P < 0.01). STE can be a feasible and useful method for animal experiments. In our rat model, strain and strain rate parameters closely reflected the improvement in intrinsic contractile function induced by exercise training.

  13. Relationship between regional myocardial blood flow and thallium-201 distribution in the presence of coronary artery stenosis and dipyridamole-induced vasodilation

    SciTech Connect

    Mays, A.E. Jr.; Cobb, F.R.

    1984-05-01

    This study assesses the relationship between the distribution of thallium-201 and myocardial blood flow during coronary vasodilation induced by intravenous dipyridamole in canine models of partial and complete coronary artery stenosis. 10 dogs were chronically instrumented with catheters in the left atrium and aorta and with a balloon occluder and electromagnetic flow probe on the proximal left circumflex coronary artery. Regional myocardial blood flow was measured during control conditions with radioisotope-labeled microspheres, and the phasic reactive hyperemic response to a 20-s transient occlusion was then recorded. Dipyridamole was then infused intravenously until phasic coronary blood flow increased to match peak hyperemic values. The left circumflex coronary artery was either partially occluded to reduce phasic blood flow to control values (group 1) or it was completely occluded (group 2), and thallium-201 and a second microsphere label were injected. 5 min later, the animals were sacrificed, the left ventricle was sectioned into 1-2-g samples, and thallium-201 activity and regional myocardial blood flow were measured. Curvilinear regression analyses between thallium-201 localization and myocardial blood flow during dipyridamole infusion demonstrated a slightly better fit to a second- as compared with a first-order model, indicating a slight roll-off of thallium activity as myocardial blood flow increases. During the dipyridamole infusion, the increases in phasic blood flow, the distributions of regional myocardial blood flow, and the relationships between thallium-201 localization and regional blood flow were comparable to values previously observed in exercising dogs with similar occlusions. These data provide basic validation that supports the use of intravenous dipyridamole and thallium-201 as an alternative to exercise stress and thallium-201 for evaluating the effects of coronary occlusive lesions on the distribution of regional myocardial blood flow.

  14. Relationship between regional myocardial blood flow and thallium-201 distribution in the presence of coronary artery stenosis and dipyridamole-induced vasodilation.

    PubMed Central

    Mays, A E; Cobb, F R

    1984-01-01

    This study assesses the relationship between the distribution of thallium-201 and myocardial blood flow during coronary vasodilation induced by intravenous dipyridamole in canine models of partial and complete coronary artery stenosis. 10 dogs were chronically instrumented with catheters in the left atrium and aorta and with a balloon occluder and electromagnetic flow probe on the proximal left circumflex coronary artery. Regional myocardial blood flow was measured during control conditions with radioisotope-labeled microspheres, and the phasic reactive hyperemic response to a 20-s transient occlusion was then recorded. Dipyridamole was then infused intravenously until phasic coronary blood flow increased to match peak hyperemic values. The left circumflex coronary artery was either partially occluded to reduce phasic blood flow to control values (group 1) or it was completely occluded (group 2), and thallium-201 and a second microsphere label were injected. 5 min later, the animals were sacrificed, the left ventricle was sectioned into 1-2-g samples, and thallium-201 activity and regional myocardial blood flow were measured. Curvilinear regression analyses between thallium-201 localization and myocardial blood flow during dipyridamole infusion demonstrated a slightly better fit to a second- as compared with a first-order model, indicating a slight roll-off of thallium activity as myocardial blood flow increases. During the dipyridamole infusion, the increases in phasic blood flow, the distributions of regional myocardial blood flow, and the relationships between thallium-201 localization and regional blood flow were comparable to values previously observed in exercising dogs with similar occlusions. These data provide basic validation that supports the use of intravenous dipyridamole and thallium-201 as an alternative to exercise stress and thallium-201 for evaluating the effects of coronary occlusive lesions on the distribution of regional myocardial blood flow

  15. Relationship between Arterial Stiffness and Blood Pressure Drop During the Sit-to-stand Test in Patients with Diabetes Mellitus

    PubMed Central

    Kobayashi, Yusuke; Kobayashi, Hideo; Sumida, Koichiro; Suzuki, Shota; Kagimoto, Minako; Okuyama, Yuki; Ehara, Yosuke; Katsumata, Mari; Fujita, Megumi; Fujiwara, Akira; Saka, Sanae; Yatsu, Keisuke; Hashimoto, Tatsuo; Kuji, Tadashi; Hirawa, Nobuhito; Toya, Yoshiyuki; Yasuda, Gen; Umemura, Satoshi

    2017-01-01

    Aim: Patients with orthostatic hypotension (OH) have high arterial stiffness. Patients with diabetes mellitus (DM) often have cardiac autonomic neuropathy that leads to OH; however, whether OH is an indicator of arterial stiffness progression is unclear. We aimed to investigate whether the cardioankle vascular index (CAVI) varies between DM patients with and without OH using the sit-to-stand test (STST). Methods: One hundred and fifty-nine patients with DM underwent CAVI assessment and blood pressure (BP) and heart rate change evaluation during the STST. OH was defined as a decline in systolic BP (SBP) and/or diastolic BP of at least 20 mmHg or 10 mmHg, respectively, in the initial and late upright positions compared with that in the sitting position. Results: OH was diagnosed in 42 patients (26.4%). DM patients with OH had significantly higher CAVI (9.36 ± 1.15 versus 8.89 ± 1.18, p = 0.026) than those without OH. CAVI was significantly inversely correlated with systolic and diastolic BP changes (R = −0.347, p <0.001 and R = −0.314, p <0.001, respectively) in the initial upright position. Multivariate regression analysis revealed that age, SBP changes, and low frequency component in the initial upright position were independent determinants of CAVI. Conclusion: Patients with DM having large BP drops occurring when moving from sitting to standing have high arterial stiffness. A significant BP drop during the STST necessitates careful evaluation of advanced arterial stiffness in patient with DM. PMID:27453255

  16. The relationship between exercise-induced muscle fatigue, arterial blood flow and muscle perfusion after 56 days local muscle unloading.

    PubMed

    Weber, Tobias; Ducos, Michel; Mulder, Edwin; Beijer, Åsa; Herrera, Frankyn; Zange, Jochen; Degens, Hans; Bloch, Wilhelm; Rittweger, Jörn

    2014-05-01

    In the light of the dynamic nature of habitual plantar flexor activity, we utilized an incremental isokinetic exercise test (IIET) to assess the work-related power deficit (WoRPD) as a measure for exercise-induced muscle fatigue before and after prolonged calf muscle unloading and in relation to arterial blood flow and muscle perfusion. Eleven male subjects (31 ± 6 years) wore the HEPHAISTOS unloading orthosis unilaterally for 56 days. It allows habitual ambulation while greatly reducing plantar flexor activity and torque production. Endpoint measurements encompassed arterial blood flow, measured in the femoral artery using Doppler ultrasound, oxygenation of the soleus muscle assessed by near-infrared spectroscopy, lactate concentrations determined in capillary blood and muscle activity using soleus muscle surface electromyography. Furthermore, soleus muscle biopsies were taken to investigate morphological muscle changes. After the intervention, maximal isokinetic torque was reduced by 23·4 ± 8·2% (P<0·001) and soleus fibre size was reduced by 8·5 ± 13% (P = 0·016). However, WoRPD remained unaffected as indicated by an unchanged loss of relative plantar flexor power between pre- and postexperiments (P = 0·88). Blood flow, tissue oxygenation, lactate concentrations and EMG median frequency kinematics during the exercise test were comparable before and after the intervention, whereas the increase of RMS in response to IIET was less following the intervention (P = 0·03). In conclusion, following submaximal isokinetic muscle work exercise-induced muscle fatigue is unaffected after prolonged local muscle unloading. The observation that arterial blood flow was maintained may underlie the unchanged fatigability.

  17. 7D.03: RELATIONSHIP BETWEEN AGE AND STRUCTURAL ALTERATIONS IN SUBCUTANEOUS SMALL RESISTANCE ARTERIES IN HYPERTENSIVE PATIENTS.

    PubMed

    De Ciuceis, C; Rossini, C; Rosei, C Agabiti; Sarkar, A; Porteri, E; La Boria, E; Gavazzi, A; Petroboni, B; Pileri, P; Rosei, E Agabiti; Rizzoni, D

    2015-06-01

    It was proposed that early vascular ageing may be an important mechanism of vascular damage in large conductance arteries. However it is not known whether aging may also affect small resistance artery morphology. For this reason, we investigated 100 patients with essential hypertension. Secondary forms of hypertension were excluded according to standard clinical evaluations and biochemical or instrumental assessments. In all patients, an evaluation of small resistance arteries morphology was performed by a wire micromyographic approach (Mulvany's technique). A small amount of subcutaneous tissue was obtained by local biopsy or during election surgery and subcutaneous small resistance arteries were dissected and mounted on a myograph; the media to lumen ratio (M/L) was then measured. The age range of our population was 22-81 years, with a mean value of 57 ± 12 years; 14% of them were current smokers, 32% had alterations in lipid patterns, none of them had diabetes mellitus, 58 were males and average blood pressure values were 156/95 ± 19/12 mmHg.We found a significant correlation between M/L and age (r = 0.30, p = 0.002): the statistical significance of the correlation persisted after correction for counfounding variables (gender, serum cholesterol, smoking status, serum glucose, systolic or diastolic blood pressure values). A statistically significant inverse correlation was also observed between internal diameter and age (r = -0.20, p = 0.046), while the correlation between age and media thickness did not reach statistical significance (r = 0.09, p = 0.37). Our data suggest that aging may affect microvascular structure in hypertensive patients. It is also possible that hypertension may anticipate the effects of physiological aging, and this should be explored in a relatively large population of normotensive subjects.

  18. CT Study of the Relationship Between the Common Iliac Artery and Vein and Their Juxtaposition: Implications for Conduit Construction Prior to Endosvascular Stent-Graft Repair of Aortic Aneurysms

    SciTech Connect

    Lenton, James; Homer-Vanniasinkam, Shervanthi; Kent, Patrick; Nicholson, Tony

    2008-11-15

    The objective of this study was to determine the anatomical relationship and juxtaposition between the common iliac artery and vein in a population of patients with aortic aneurysmal disease and a population clinically and radiologically free of atheroma. It was a retrospective study of 100 consecutive patients undergoing computed tomographic assessment of abdominal aortic aneurysm prior to endovascular or open surgical repair and 100 patients undergoing computed tomographic assessment for other pathologies who did not have clinical or imaging signs of aorto-iliac atheroma. In both groups the anatomical relationship between the right and left iliac artery and vein was studied, and the thickness of the fat plane separating the artery from the vein measured. The right iliac vein was posterolateral to the artery at the level of the common iliac artery bifurcation in 95% of patients in both groups. At the same level the left iliac vein was posterior in 23% (p {<=} 0.001). Eighty-three percent of patients in the aneurysm group had a fat plane between the right artery and vein that measured 0 mm (no visible fat plane = 52%) to 1 mm (= 31%). Ninety-eight percent of patients in the aneurysm group had a measurable fat plane between the left iliac artery and vein of up to 5 mm (p = 0.001). Six percent of the control group demonstrated no visible fat plane between the right iliac artery and vein (p {<=} 0.001), while the fat plane measured more than 1 mm (1-5 mm) on the left in 100%. We conclude that in patients where conduit construction is required for aortic stent-graft access, the anatomical configuration and intimate relationship of the iliac arteries and veins should be assessed and taken into account at CT scan evaluation. The distal right common iliac artery should not be used, as venous damage can be predicted from the anatomical and intimate relationship of the iliac artery and vein at this level in patients with atheroma and the difficulties this relationship

  19. Evaluation of the pressure-volume-temperature (PVT) data of water from experiments and molecular simulations since 1990

    NASA Astrophysics Data System (ADS)

    Guo, Tao; Hu, Jiawen; Mao, Shide; Zhang, Zhigang

    2015-08-01

    Since 1990, many groups of pressure-volume-temperature (PVT) data from experiments and molecular dynamics (MD) or Monte Carlo (MC) simulations have been reported for supercritical and subcritical water. In this work, fifteen groups of PVT data (253.15-4356 K and 0-90.5 GPa) are evaluated in detail with the aid of the highly accurate IAPWS-95 formulation. The evaluation gives the following results: (1) Six datasets are found to be of good accuracy. They include the simulated results based on SPCE potential above 100 MPa and those derived from sound velocity measurements, but the simulated results below 100 MPa have large uncertainties. (2) The data from measurements with a piston cylinder apparatus and simulations with an exp-6 potential contain large uncertainties and systematic deviations. (3) The other seven datasets show obvious systematic deviations. They include those from experiments with synthesized fluid inclusion techniques (three groups), measured velocities of sound (one group), and automated high-pressure dilatometer (one group) and simulations with TIP4P potential (two groups), where the simulated data based on TIP4P potential below 200 MPa have large uncertainties. (4) The simulated data but those below 1 GPa agree with each other within 2-3%, and mostly within 2%. The data from fluid inclusions show similar systematic deviations, which are less than 2-5%. The data obtained with automated high-pressure dilatometer and those derived from sound velocity measurements agree with each other within 0.3-0.6% in most cases, except for those above 10 GPa. In principle, the systematic deviations mentioned above, except for those of the simulated data below 1 GPa, can be largely eliminated or significantly reduced by appropriate corrections, and then the accuracy of the relevant data can be improved significantly. These are very important for the improvement of experiments or simulations and the refinement and correct use of the PVT data in developing

  20. Exponential analysis of the lung pressure-volume curve in patients with chronic pigeon-breeder's lung.

    PubMed

    Sansores, R; Perez-Padilla, R; Paré, P D; Selman, M

    1992-05-01

    Pigeon-breeder's lung (PBL) is extremely common in Mexico City and often progresses to irreversible pulmonary fibrosis. The exponential analysis of the lung pressure-volume (PV) curve (V = A - Be-kp) has been suggested as a method to separate the lung restriction caused by inflammation from that caused by pulmonary fibrosis; a significantly decreased value for the exponential constant, k, suggests a change in the mechanical properties of the functioning lung parenchyma, while a normal value accompanied by restriction suggests subtraction of lung units without a change in the mechanical properties of the functioning units. We measured lung volumes and static PV curves in 29 patients who had persistent lung restriction following a biopsy-proven diagnosis of PBL. Mean values in the 29 subjects were as follows: age, 43 +/- 13 years; TLC, 61 +/- 15 percent of predicted; VC, 46 +/- 19 percent of predicted; and k, 55 +/- 17 percent of predicted. Twenty-four of the 29 patients had values for k that were below the 95 percent confidence level, and five had "normal" values. There was no difference in TLC and VC (percent of predicted) between those with or without a decreased value for k. Four of five patients with a normal value for k improved subsequent to diagnosis, while only one of 21 patients with a decreased k improved. We conclude that increased lung elasticity manifested by a low value for k is common in patients with chronic PBL. These results support the observation of frequent irreversible lung fibrosis in these patients. Measurements of k could prove a good prognostic indicator at the time of initial diagnosis.

  1. Global and regional assessment of sustained inflation pressure-volume curves in patients with acute respiratory distress syndrome.

    PubMed

    Becher, Tobias; Rostalski, Philipp; Kott, Matthias; Adler, Andy; Schadler, Dirk; Weiler, Norbert; Frerichs, Inez

    2017-03-24

    Static or quasi-static pressure-volume (P-V) curves can be used to determine the lung mechanical properties of patients suffering from acute respiratory distress syndrome (ARDS). According to the traditional interpretation, lung recruitment occurs mainly below the lower point of maximum curvature (LPMC) of the inflation P-V curve. Although some studies have questioned this assumption, setting of positive end-expiratory pressure 2 cmH2O above the LPMC was part of a "lung-protective" ventilation strategy successfully applied in several clinical trials. The aim of our study was to quantify the amount of unrecruited lung at different clinically relevant points of the P-V curve. P-V curves and electrical impedance tomography (EIT) data from 30 ARDS patients were analysed. We determined the regional opening pressures for every EIT image pixel and fitted the global P-V curves to five sigmoid model equations to determine the LPMC, inflection point (IP) and upper point of maximal curvature (UPMC). Points of maximal curvature and IP were compared between the models by one-way analysis of variance (ANOVA). The percentages of lung pixels remaining closed ("unrecruited lung") at LPMC, IP and UPMC were calculated from the number of lung pixels exhibiting regional opening pressures higher than LPMC, IP and UPMC and were also compared by one-way ANOVA. As results, we found a high variability of LPMC values among the models, a smaller variability of IP and UPMC values. We found a high percentage of unrecruited lung at LPMC, a small percentage of unrecruited lung at IP and no unrecruited lung at UPMC. Our results confirm the notion of ongoing lung recruitment at pressure levels above LPMC for all investigated model equations and highlight the importance of a regional assessment of lung recruitment in patients with ARDS.

  2. Comparison of Pressure-Volume Loop and Echocardiographic Measures of Diastolic Function in Patients with Single Ventricle Physiology

    PubMed Central

    Chowdhury, Shahryar M.; Butts, Ryan J.; Buckley, Jason; Hlavacek, Anthony M.; Hsia, Tain-Yen; Khambadkone, Sachin; Baker, G. Hamilton

    2014-01-01

    Background Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single ventricle population. We hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with single ventricle physiology. Materials and Methods Conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (tau), maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness, μ. Echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and TDI-derived isovolumic relaxation time (IVRT′). The correlation between PVL and echocardiographic measures was examined. Results Thirteen patients were enrolled at various stages of surgical palliation. Median age was 3yr (range 3mo to 19yr). Tau correlated well with Doppler E:A (r = 0.832, p = 0.005), lateral E:E′ (r = 0.747, p = 0.033), and IVRT′ (r = 0.831, p = 0.001). There was also correlation between peak -dP/dt and IVRT′ (r = 0.609, p = 0.036) while μ also correlated with IVRT′ (r = 0.884, p = 0.001). Conclusion This study represents the first-ever comparison of diastolic echocardiographic and PVL indices in a single ventricle population. We found that Doppler E:A, lateral E:E′, and IVRT′ correlate well with PVL measures of diastolic function. This study supports the further validation of echocardiographic measures of diastolic function vs. PVL measures of diastolic function in the single ventricle population.. PMID:24584211

  3. Comparison of pressure-volume loop and echocardiographic measures of diastolic function in patients with a single-ventricle physiology.

    PubMed

    Chowdhury, Shahryar M; Butts, Ryan J; Buckley, Jason; Hlavacek, Anthony M; Hsia, Tain-Yen; Khambadkone, Sachin; Baker, G Hamilton

    2014-08-01

    Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single-ventricle population. The authors hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with a single-ventricle physiology. The conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (τ), the maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness (μ). The echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and the TDI-derived isovolumic relaxation time (IVRT'). The correlation between PVL and echocardiographic measures was examined. The study enrolled 13 patients at various stages of surgical palliation. The median age of the patients was 3 years (range 3 months to 19 years). τ correlated well with Doppler E:A (r = 0.832; p = 0.005), lateral E:E' (r = 0.747; p = 0.033), and IVRT' (r = 0.831; p = 0.001). Peak -dP/dt also was correlated with IVRT' (r = 0.609; p = 0.036), and μ also was correlated with IVRT' (r = 0.884; p = 0.001). This study represents the first-ever comparison of diastolic echocardiographic and PVL indices in a single-ventricle population. The findings show that Doppler E:A, lateral E:E', and IVRT' correlate well with PVL measures of diastolic function. This study supports further validation of echocardiographic measures of diastolic function versus PVL measures of diastolic function in the single-ventricle population.

  4. Factors affecting the relationship between arterial and end-tidal carbon dioxide pressures in the anaesthetised horse.

    PubMed

    Rainger, J E; Dart, C M; Perkins, N R

    2010-01-01

    To assess the effects of the duration of anaesthesia, position of recumbency, mode of ventilation, anaesthetic drug protocol, patient age and type of surgical procedure on the usefulness of capnometry as a measure of the partial pressure of arterial carbon dioxide (P(a)co(2)) during general anaesthesia in horses. A prospective study compared the P(a)co(2) values with those of partial pressure of end-tidal carbon dioxide (ETco(2)) in horses anaesthetised for elective or emergency surgical procedures. The difference between P(a)co(2) and ETco(2) (P(a)co(2)- ETco(2)) and the physiological dead space to tidal volume ratio (V(D)/V(T)) were calculated. The effects of the study parameters on these variables was determined. The agreement between P(a)co(2) and ETco(2) was poor. P(a)co(2)- ETco(2) and V(D)/V(T) during the first 60 min of anaesthesia was significantly less than after 60 min of anaesthesia. Mode of ventilation, position of recumbency, anaesthetic drug protocol, patient age and type of procedure did not have a significant affect on either value. P(a)co(2)- ETco(2) in anaesthetised horses can be large, making ETco(2) unreliable as a predictor of P(a)co(2) and for assessment of pulmonary ventilation. For anaesthesia lasting less than 60 min at least one blood gas analysis of an arterial blood sample is required to assess P(a)co(2)- ETco(2). Arterial blood gas analysis should be repeated after 60 min of general anaesthesia.

  5. Influence of isoflurane on the diastolic pressure-flow relationship and critical occlusion pressure during arterial CABG surgery: a randomized controlled trial.

    PubMed

    Hinz, José; Mansur, Ashham; Hanekop, Gerd G; Weyland, Andreas; Popov, Aron F; Schmitto, Jan D; Grüne, Frank F G; Bauer, Martin; Kazmaier, Stephan

    2016-01-01

    The effects of isoflurane on the determinants of blood flow during Coronary Artery Bypass Graft (CABG) surgery are not completely understood. This study characterized the influence of isoflurane on the diastolic Pressure-Flow (P-F) relationship and Critical Occlusion Pressure (COP) during CABG surgery. Twenty patients undergoing CABG surgery were studied. Patients were assigned to an isoflurane or control group. Hemodynamic and flow measurements during CABG surgery were performed twice (15 minutes after the discontinuation of extracorporeal circulation (T15) and again 15 minutes later (T30)). The zero flow pressure intercept (a measure of COP) was extrapolated from a linear regression analysis of the instantaneous diastolic P-F relationship. In the isoflurane group, the application of isoflurane significantly increased the slope of the diastolic P-F relationship by 215% indicating a mean reduction of Coronary Vascular Resistance (CVR) by 46%. Simultaneously, the Mean Diastolic Aortic Pressure (MDAP) decreased by 19% mainly due to a decrease in the systemic vascular resistance index by 21%. The COP, cardiac index, heart rate, Left Ventricular End-Diastolic Pressure (LVEDP) and Coronary Sinus Pressure (CSP) did not change significantly. In the control group, the parameters remained unchanged. In both groups, COP significantly exceeded the CSP and LVEDP at both time points. We conclude that short-term application of isoflurane at a sedative concentration markedly increases the slope of the instantaneous diastolic P-F relationship during CABG surgery implying a distinct decrease with CVR in patients undergoing CABG surgery.

  6. Effect of Betamethasone on Fetal Pulmonary and Umbilical Artery Doppler Velocimetry and Relationship With Respiratory Distress Syndrome Development.

    PubMed

    Güngör, Emre Sinan; İlhan, Gülşah; Gültekin, Hüseyin; Zebitay, Ali Galip; Cömert, Serdar; Verit, Fatma Ferda

    2017-06-19

    Respiratory distress syndrome (RDS) is a major cause of neonatal morbidity and mortality. It is primarily a disease of premature neonates. The aim of this study was to evaluate the impact of maternal betamethasone administration on the fetal pulmonary arteries (PAs) and umbilical arteries (UAs) and the correlation between RDS development and PA Doppler results. Forty singleton pregnancies between 24 and 34 gestational weeks with a diagnosis of preterm birth were included prospectively. They received corticosteroids to enhance fetal lung maturity. Fetal PA and UA Doppler parameters were evaluated before and 48 to 72 hours after steroid administration. Maternal records were matched to neonatal charts, and demographic and outcome data were abstracted. There were no differences between groups for maternal age, body mass index, mode of delivery, and mean GA at steroid administration. Apgar scores at 1 and 5 minutes were significantly lower for neonates who developed RDS (P < .05). There were no statistically significant differences in PA Doppler results between fetuses who developed RDS and those who did not, and there were no significant differences in PA Doppler results before and after steroid administration for both groups. The UA pulsatility and resistive indices were significantly lower after steroid administration for the neonates who developed RDS (P < .05). There were no significant differences in PA Doppler indices for fetuses with or without RDS after steroid administration. © 2017 by the American Institute of Ultrasound in Medicine.

  7. Radiographic quantification of chronic dental infection and its relationship to the atherosclerotic process in the carotid arteries.

    PubMed

    Friedlander, Arthur H; Sung, Eric C; Chung, Evelyn M; Garrett, Neal R

    2010-04-01

    Atherosclerosis may be initiated/accelerated by chronic dental infection (CDI). Noninvasively visualizing the carotid arteries is an accepted surrogate marker for determining coronary artery atherosclerosis (CAA). We hypothesized that 36 individuals with radiographic carotid atheromas would have more radiographic CDI than risk-matched individuals without atheromas. We determined the arithmetic sum of individuals' periapical and furcal lesions, pericoronitis sites, carious roots, teeth with pulpal caries, and vertical bony defects (>4 mm). Individuals with atheromas had a significantly (P < .01) greater mean score of 15.5 +/- 10.4 compared with control subjects (7.9 +/- 8.1). Similarly significant (P < .05) was the difference in the mean numbers of mesial and distal vertical bony defects in the atheroma group (4.1 +/- 3.9 and 4.8 +/- 3.8, respectively) compared with control subjects (1.6 +/- 2.4 and 1.8 +/- 2.7, respectively). Individuals with atheromas on their radiographs (and high probability of CAA) had significantly greater amounts of CDI than individuals without atheromas. Published by Mosby, Inc.

  8. Relationship between body mass index and mean arterial pressure in normotensive and chronic hypertensive pregnant women: a prospective, longitudinal study.

    PubMed

    Guedes-Martins, Luís; Carvalho, Mariana; Silva, Catarina; Cunha, Ana; Saraiva, Joaquim; Macedo, Filipe; Almeida, Henrique; Gaio, A Rita

    2015-10-30

    Being overweight is associated with both higher systolic blood pressure (SBP) and diastolic blood pressure (DBP) during pregnancy and increased risk of gestational hypertensive disorders. The objective of this study was to determine and quantify the effect of body mass index (BMI) on mean arterial pressure (MAP) at several time points throughout pregnancy in normotensive (NT) and chronic hypertensive pregnant (HT) women. A prospective longitudinal study was carried out in 461 singleton pregnancies (429 low-risk and 32 with chronic arterial hypertension), with measurements taken at the 1(st), 2(nd), and 3(rd) trimesters and at delivery. Linear mixed-effects regression models were used to evaluate the time-progression of BMI, SBP, DBP and MAP during pregnancy (NT vs. HT). The longitudinal effect of BMI on MAP, adjusted for the hypertensive status, was investigated by the same methodology. BMI consistently increased with time in both NT and HT women. In contrast, MAP decreased during the first half of pregnancy, after which it increased until the moment of delivery in both groups. A 5-unit increase in BMI was predicted to produce an increase of approximately 1 mmHg in population MAP values. This effect is independent from the time period and from hypertensive status. In both NT and HT pregnant women, MAP is strongly (and significantly) influenced by increases in BMI.

  9. The relationship between arterial carbon dioxide tension and end-tidal carbon dioxide tension in intubated adults with traumatic brain injuries who required emergency craniotomies.

    PubMed

    Dyer, Brett A; White, William A; Lee, Doohee; Elkins, Laurie; Slayton, Donna J

    2013-01-01

    Anesthetic management of patients who have suffered traumatic brain injuries can be challenging. We investigated the relationship between arterial to end-tidal carbon dioxide partial pressure gradients (Pa-etCO₂) and 3 predictor variables: (1) injury severity score, (2) use of positive end-expiratory pressure, and (3) presence of rib fractures. Using a convenient sampling method, we sampled 56 patients who arrived to the operating room intubated after traumatic brain injuries between 2005 and 2011. Two groups were compared retrospectively: those with Pa-etCO₂ greater than 10 mm Hg (case group) (n = 37) and those with Pa-etCO₂ gradients of 10 mm Hg or less (control group) (n = 19). Descriptive and inferential statistics were employed to identify any differences between the groups. Stepwise regression was also performed. Cross tabulation analysis revealed that injury severity score of 30 or more was a predictor of Pa-etCO₂ gradient. Stepwise regression analysis revealed the presence of rib fracture and body mass index to be significant predictors of Pa-etCO₂ gradient (P < .011). This study identified coexisting conditions in which the patients' Pa-etCO₂ gradients were large. Results showed that injury severity score of 30 or more, the presence of rib fractures, and higher body mass index were statistically significant predictors of Pa-etCO₂ gradients greater than 10 mm Hg. These observations should be considered when evaluating PetCO₂ in conjunction with arterial blood gas analysis to determine optimal ventilation status of these patients.

  10. Superior and anterior inferior cerebellar arteries and their relationship with cerebello-pontine angle cranial nerves revisited in the light of cranial cephalometric indexes: a cadaveric study.

    PubMed

    Habibi, Zohreh; Meybodi, Ali Tayebi; Maleki, Farid; Tabatabai, Seyed

    2011-01-01

    The aim was to clarify the anatomical features of the superior and anterior inferior cerebellar arteries in relation to the trigeminal nerve and acoustic-facial complex and to the bony structures of the skull in a sample of male Iranian cadavers. Bilateral dissections, calvariectomy, and brain evacuation were performed on 31 adult human fresh brains and skull bases to assess the neurovascular associations, and skull base morphometry. Equations were defined to estimate posterior fossa volume and the relationships between bony and neurovascular elements. Eight SCAs were duplicated from origin. There were 9 cases of SCA-trigeminal contacts, which were at the root entry zone in 7. Mean distance from the origin of AICA to the vertebrobasilar junction was 11.80 mm, while 79% of AICAs originated from the lower half of the BA. This was significantly associated with "posterior fossa funneling" and "basilar narrowing" indexes. In most cases AICA crossed the acoustic-facial complex and coursed between neural bundles (48.3%). The AICA reached or entered the internal acoustic canal in 22.6% of cases and was medial to porous in 77.4%. We documented anatomical variations of the superior and anterior inferior cerebellar arteries along with some cephalometric equations with relevant neurovascular anatomy in Iranian cadavers.

  11. The Relationship of Serum Soluble Fas Ligand (sFasL) Level with the Extent of Coronary Artery Disease

    PubMed Central

    Sahinarslan, Asife; Boyaci, Bulent; Kocaman, Sinan Altan; Topal, Salih; Ercin, Ugur; Okyay, Kaan; Bukan, Neslihan; Yalçin, Ridvan; Cengel, Atiye

    2012-01-01

    Fas/Fas ligand system contributes to the programmed cell death induced by myocardial ischemia. We investigated whether serum soluble Fas ligand (sFasL) level is independently related with the severity and extent of angiographically assessed coronary artery disease (CAD). We included 169 patients in this study. Two groups were formed based on the existence of a lesion on coronary angiography. First group included patients with normal coronary arteries (NCA; n = 53). Patients with atherosclerotic lesions were included in the second group (n = 116). We used the coronary vessel score (the number of the coronary arteries with a lesion leading to ≥ 50% luminal obstruction) and the Azar score to determine the extent and the severity of CAD. Standard enzyme-linked immunosorbent assay kits were used to measure serum sFasL levels. The serum sFasL level was higher in patients with CAD than in patients with NCA (0.52 ± 0.23 mU/mL vs. 0.45 ± 0.18 mU/mL, p = 0.023). The sFasL level correlated with Azar score (r = 0.231, p = 0.003) and with coronary vessel score (r = 0.269, p < 0.001). In the multivariate analysis, we found that age (beta: 0.188, p = 0.008), gender (beta: 0.317, p < 0.001), diabetes mellitus (DM; beta: 0.195, p = 0.008), and sFasL level (beta: 0.209, p = 0.003) were independently related with Azar score. When we used coronary vessel score as the dependent variable, we found that age (p = 0.020), gender (p < 0.001), DM (p = 0.006), and sFasL level (p = 0.001) were independent predictors. Serum sFasL level is associated with angiographically more severe CAD. Our findings suggest that sFasL level may be a biochemical surrogate of severe coronary atherosclerosis. PMID:23450131

  12. The Relationship of Serum Soluble Fas Ligand (sFasL) Level with the Extent of Coronary Artery Disease.

    PubMed

    Sahinarslan, Asife; Boyaci, Bulent; Kocaman, Sinan Altan; Topal, Salih; Ercin, Ugur; Okyay, Kaan; Bukan, Neslihan; Yalçin, Ridvan; Cengel, Atiye

    2012-03-01

    Fas/Fas ligand system contributes to the programmed cell death induced by myocardial ischemia. We investigated whether serum soluble Fas ligand (sFasL) level is independently related with the severity and extent of angiographically assessed coronary artery disease (CAD). We included 169 patients in this study. Two groups were formed based on the existence of a lesion on coronary angiography. First group included patients with normal coronary arteries (NCA; n = 53). Patients with atherosclerotic lesions were included in the second group (n = 116). We used the coronary vessel score (the number of the coronary arteries with a lesion leading to ≥ 50% luminal obstruction) and the Azar score to determine the extent and the severity of CAD. Standard enzyme-linked immunosorbent assay kits were used to measure serum sFasL levels. The serum sFasL level was higher in patients with CAD than in patients with NCA (0.52 ± 0.23 mU/mL vs. 0.45 ± 0.18 mU/mL, p = 0.023). The sFasL level correlated with Azar score (r = 0.231, p = 0.003) and with coronary vessel score (r = 0.269, p < 0.001). In the multivariate analysis, we found that age (beta: 0.188, p = 0.008), gender (beta: 0.317, p < 0.001), diabetes mellitus (DM; beta: 0.195, p = 0.008), and sFasL level (beta: 0.209, p = 0.003) were independently related with Azar score. When we used coronary vessel score as the dependent variable, we found that age (p = 0.020), gender (p < 0.001), DM (p = 0.006), and sFasL level (p = 0.001) were independent predictors. Serum sFasL level is associated with angiographically more severe CAD. Our findings suggest that sFasL level may be a biochemical surrogate of severe coronary atherosclerosis.

  13. Thermochemical and pressure-volume-temperature systematics of data on solids, examples: Tungsten and MgO

    NASA Astrophysics Data System (ADS)

    Saxena, S. K.; Zhang, J.

    1990-01-01

    Data systematization using the constraints from the equation Cp = Cv + α _P {}^2V_T K_T T where C p, C v, α p, K T and V are respectively heat capacity at constant pressure, heat capacity at constant volume, isobaric thermal expansion, isothermal bulk modulus and molar volume, has been performed for tungsten and MgO. The data are K_T (W) = 1E - 5/(3.1575E - 12 + 1.6E - 16T + 3.1E - 20T^2 ) α _P (W) = 9.386E - 6 + 5.51E - 9T C_P (W) = 24.1 + 3.872E - 3T - 12.42E - 7T^2 + 63.96E - 11T^3 - 89000T^{ - 2} K_T (MgO) = 1/(0.59506E - 6 + 0.82334E - 10T + 0.32639E - 13T^2 + 0.10179E - 17T^3 α _P (MgO) = 0.3754E - 4 + 0.7907E - 8T - 0.7836/T^2 + 0.9148/T^3 C_P (MgO) = 43.65 + 0.54303E - 2T - 0.16692E7T^{ - 2} + 0.32903E4T^{ - 1} - 5.34791E - 8T^2 For the calculation of pressure-volume-temperature relation, a high temperature form of the Birch-Murnaghan equation is proposed P = 3K_T (1 + 2f)^{5/2} (1 + 2ξ f) Where K_T = 1/(b_0 + b_1 T + b_2 T^2 + b_3 T^3 ) f = (1/2)\\{ [V(1,T)/V(P,T)]^{2/3} - 1\\} ξ = ({3 4})[K'_0 + K'_1 ln ({T {300}}} - 4] where in turn V(1,T) = V_0 [exp (intlimits_{300}^T {α dT)]} . The temperature dependence of the pressure derivative of the bulk modulus (K'1) is estimated by using the shock-wave data. For tungsten the data are K'0 = 3.5434, K'1 = 0.032; for MgO K'0 = 4.17 and K'1 = 0.1667. For calculating the Gibbs free energy of a solid at high pressure and at temperatures beyond that of melting at 1 atmosphere, it is necessary to define a high-temperature reference state for the fictive solid.

  14. The pressure-volume equation of state of a synthetic grossular Ca3Al2Si3O12

    NASA Astrophysics Data System (ADS)

    Milani, Sula; Boffa Ballaran, Tiziana; Nestola, Fabrizio

    2014-05-01

    In the framework of a wide research project focused on mineral inclusions in diamonds we have investigated the compressibility of a synthetic grossular garnet (Ca3Al2Si3O12) with the purpose of providing new constraints on the diamond geobarometry. In fact, not only garnets are among the important phases of the Earth upper mantle but at the same time are one of the main phases found as inclusion in diamonds. Garnets are a crucial marker in determining the origin source of diamonds, which can be eclogitic and/or peridotitic. In particular, peridotitic diamonds include garnets characterized by about 90-92% of pyrope-almandine with the grossular component reaching about 6-8%, whereas eclogitic diamonds have garnets with the grossular component increased up to about 20-22%. In order to obtain information about the depth of formation of the diamond-garnet pair, beyond the classical chemical method, we propose the so called "elastic method", which is based on the knowledge of precise and accurate thermoelastic parameters for both diamond and inclusion (e.g. Nestola et al. 2011 and references therein). We have determined the pressure - volume equation of state of a pure synthetic grossular garnet by single-crystal X-ray diffraction up to about 8 GPa. The resulting equation of state coefficients, together with those previously determined for pyrope and almandine end-members and their intermediate compositions (see Milani et al. 2013) will cover the compositional range of garnets found as inclusions in diamonds, allowing to construct a robust model to predict the elastic parameters for any garnet composition typical of eclogitic and/or peridotitic diamond. The research was funded by the ERC Starting Grant to FN (grant agreement n° 307322). References Milani S., Mazzucchelli M., Nestola F., Alvaro M., Angel R.J., Geiger C.A., Domeneghetti M.C. (2013) The P-T conditions of garnet inclusion formation in diamond: thermal expansion of synthetic end-member pyrope. EGU General

  15. Angiocardiographic pressure volume loops in the analysis of right ventricular function after repair of tetralogy of Fallot.

    PubMed

    Uebing, Anselm; Fischer, Gunther; Schmiel, Friedrich; Onnasch, Dietrich G W; Scheewe, Jens; Kramer, Hans-Heiner

    2005-10-01

    The objective of the study was to estimate the capacity of pressure volume (PV) loop analysis to assess right ventricular (RV) function after Fallot (TOF) repair. Fifty six patients were examined after TOF repair. PV loops were constructed from RV angiocardiography and simultaneous pressure measurement. Patients were divided in three groups according to RV size and pressure (Group I: normal RV size and pressure; group II: enlarged RV, near normal pressure; group III: normal RV size, elevated pressure). Systolic stroke work corrected for body surface area (W/BSA) and for RV enddiastolic volume (W/EDV), peak RV filling (PFR) and emptying rates (PER) corrected for RV stroke volume, cycle efficiency (CE), RV ejection fraction (RVEF). W/BSA was significantly higher in group II than in group I (0.19 +/- 0.05 vs. 0.11 +/- 0.04 J/m(2), p < 0.001) and was similar between groups II and III (0.19 +/- 0.05 vs. 0.17 +/- 0.05 J/m(2) ; NS). W/EDV was similar in groups I and II (12.4 +/- 5.4 vs. 12.4 +/- 2.9 mmHg; NS). CE was smallest in group II. The difference was significant between groups II and III (0.62 +/- 0.08 vs. 0.73 +/- 0.09; p < 0.05). RVEF was negatively correlated to RV end systolic volume (RVESV) in the patients of groups I and II (r = -0.32, p < 0.05). A similar correlation was found between PFR and RVESV (r = -0.28, p < 0.05). Analysis of a single PV loop allows quantification of RV load after TOF repair. W/BSA is increased to the same extent under volume and pressure load. The lack of decrease in W/EDV in patients with enlarged RV indicates that RV is capable to perform adequate work in a wide range. RVESV is a useful measure for estimating RV function after TOF repair depicting parameters of systolic and diastolic RV function.

  16. Relationship Between Ambulatory Arterial Stiffness Index (Aasi) And Night/Day Blood Pressure Ratio In Essential hypertensives.

    PubMed

    Di Raimondo, Domenico; Casuccio, Alessandra; Di Liberti, Rosangela; Musiari, Gaia; Zappulla, Valentina; D'angelo, Alessandra; Pinto, Antonio

    2017-06-21

    Ambulatory Arterial Stiffness Index (AASI) has been proposed as an indirect and simpler method to estimate the Arterial Stiffness (AS). AASI, calculated from a set of data collected during a 24-hours ambulatory blood pressure monitoring (ABPM), is defined as 1 minus the regression slope of diastolic on systolic blood pressure (BP) values. For a given increase in diastolic BP, the increase in systolic BP is smaller in a compliant compared to a stiff artery; the stiffer the arterial tree, the closer AASI is to 1. AASI demonstrated to predict cardiovascular mortality, cerebrovascular events and to be associated with target organ damage. Taking into account the almost completely absence of data regarding the ability of AASI to predict the different degree of AS when hypertensives are divided into four class of dipping in relation to the extent of the nocturnal reduction of BP (extreme dippers, dippers, mild dippers and reverse dippers) aim of the study was to clarify the ability of AASI to estimate the different degree of AS of hypertensive subjects with different nocturnal BP profile and resulting different extent of organ damage. We enrolled 816 subjects (403 men and 413 women) with essential hypertension, referred to the U.O.C of Medicina Interna e Cardioangiologia of the University of Palermo; 173 subjects (71 men and 102 women, mean age 44.4 ± 14.6 years) without a history of hypertension were enrolled as controls. The analysis of data was performed by dividing the populating into four categories in relation to the extent of the nocturnal decline of BP: 124 extreme dipper (mean age 54,8 ± 12,4 years, men 46.8 %); 287 dipper (mean age 55,9 ± 14,2 years, men 54,0 %); 271 mild dipper (mean age 61,5 ± 14,7 years, men 52,0 %); 134 reverse dipper (mean age 61,5 ± 14,7 years, men 33.6 %). The mean value of AASI was significantly higher for mild and reverse dippers versus control patients and versus the other categories of dipping. The multiple regression analysis

  17. Relationship of serum osteoprotegerin levels with coronary artery disease severity, left ventricular hypertrophy and C-reactive protein.

    PubMed

    Rhee, Eun-Jung; Lee, Won-Young; Kim, Se-Yeon; Kim, Byung-Jin; Sung, Ki-Chul; Kim, Bum-Su; Kang, Jin-Ho; Oh, Ki-Won; Oh, Eun-Sook; Baek, Ki-Hyun; Kang, Moo-Ii; Woo, Hee-Yeon; Park, Hyo-Soon; Kim, Sun-Woo; Lee, Man-Ho; Park, Jung-Roe

    2005-03-01

    OPG (osteoprotegerin) is an inhibitor of osteoclastogenesis and recent work suggests it has a role in atherosclerosis. Therefore we measured serum OPG levels in patients with coronary artery disease, compared the serum OPG levels among the different groups according to the number of stenotic vessels and determined whether there was any correlation with aortic calcification, LV (left ventricular) mass index and serum CRP (C-reactive protein) levels. Subjects (n=100; mean age, 57 years) who underwent coronary angiograms were enrolled. Blood pressure, body mass index, fasting blood glucose, lipid profiles and CRP levels were measured and the LV mass indices were calculated using ECGs. Serum OPG levels were measured by ELISA. The presence of calcification in the aortic notch was checked by a chest X-ray. The subjects were divided into four groups according to the number of stenotic vessels. The mean serum OPG levels increased significantly as the number of stenotic vessels increased, and the mean serum OPG levels were higher in the group with three-vessel disease compared with the groups with no- or one-vessel disease. The mean serum CRP level was significantly higher in the group with three-vessel disease compared with the groups with no-, one- and two-vessel disease. Age and LV mass index showed significant positive correlations with serum OPG levels, although significance was lost after an adjustment for age. Serum CRP levels were positively correlated with serum OPG levels even after an adjustment for age. There were no differences in serum OPG levels according to the presence of fasting hyperglycaemia or aortic calcification. In conclusion, serum OPG level was related to the severity of stenotic coronary arteries and serum CRP levels. LV mass indices showed no significant correlation with OPG levels. The precise mechanism for the role of OPG in atherosclerosis needs to be investigated further.

  18. Relationships Among Conventional Cardiovascular Risk Factors and Lifestyle Habits With Arterial Stiffness in Type 2 Diabetic Patients

    PubMed Central

    Hamamura, Misako; Mita, Tomoya; Osonoi, Yusuke; Osonoi, Takeshi; Saito, Miyoko; Tamasawa, Atsuko; Nakayama, Shiho; Someya, Yuki; Ishida, Hidenori; Gosho, Masahiko; Kanazawa, Akio; Watada, Hirotaka

    2017-01-01

    Background While conventional cardiovascular risk factors and certain lifestyle habits are associated with arterial stiffness in patients with type 2 diabetes mellitus (T2DM), it is still unknown whether they are actually associated with arterial stiffness even after adjustment for conventional cardiovascular risk factors and lifestyle habits. The aim of this study was to identify variables that are associated with brachial-ankle pulse wave velocity (baPWV). Methods The study participants comprised 724 Japanese T2DM outpatients free of history of cardiovascular diseases. Lifestyle habits were analyzed using self-reported questionnaires. The associations among conventional cardiovascular risk factors and lifestyle habits with baPWV were investigated by multivariable linear regression analysis. Results The mean age of the study subjects was 57.8 ± 8.6 years, and 62.8% of those were males. The mean HbA1c was 7.0±1.0%, and the estimated duration of T2DM was 9.9 ± 7.2 years. Multiple linear regression analysis that included age and gender demonstrated that age and male sex were positively associated with baPWV. In a model adjusted for numerous conventional cardiovascular risk factors and lifestyle habits, age, duration of T2DM, systolic blood pressure, serum uric acid, urinary albumin excretion and poor sleep quality were positively associated with baPWV, while body mass index was negatively associated with baPWV. Conclusions In Japanese T2DM, in addition to several conventional cardiovascular risk factors, poor sleep quality was associated with baPWV even after adjustment for numerous conventional cardiovascular risk factors and lifestyle habits. PMID:28270889

  19. Relationships Among Conventional Cardiovascular Risk Factors and Lifestyle Habits With Arterial Stiffness in Type 2 Diabetic Patients.

    PubMed

    Hamamura, Misako; Mita, Tomoya; Osonoi, Yusuke; Osonoi, Takeshi; Saito, Miyoko; Tamasawa, Atsuko; Nakayama, Shiho; Someya, Yuki; Ishida, Hidenori; Gosho, Masahiko; Kanazawa, Akio; Watada, Hirotaka

    2017-04-01

    While conventional cardiovascular risk factors and certain lifestyle habits are associated with arterial stiffness in patients with type 2 diabetes mellitus (T2DM), it is still unknown whether they are actually associated with arterial stiffness even after adjustment for conventional cardiovascular risk factors and lifestyle habits. The aim of this study was to identify variables that are associated with brachial-ankle pulse wave velocity (baPWV). The study participants comprised 724 Japanese T2DM outpatients free of history of cardiovascular diseases. Lifestyle habits were analyzed using self-reported questionnaires. The associations among conventional cardiovascular risk factors and lifestyle habits with baPWV were investigated by multivariable linear regression analysis. The mean age of the study subjects was 57.8 ± 8.6 years, and 62.8% of those were males. The mean HbA1c was 7.0±1.0%, and the estimated duration of T2DM was 9.9 ± 7.2 years. Multiple linear regression analysis that included age and gender demonstrated that age and male sex were positively associated with baPWV. In a model adjusted for numerous conventional cardiovascular risk factors and lifestyle habits, age, duration of T2DM, systolic blood pressure, serum uric acid, urinary albumin excretion and poor sleep quality were positively associated with baPWV, while body mass index was negatively associated with baPWV. In Japanese T2DM, in addition to several conventional cardiovascular risk factors, poor sleep quality was associated with baPWV even after adjustment for numerous conventional cardiovascular risk factors and lifestyle habits.

  20. The relationship between serum thyroid hormone levels, subclinical hypothyroidism, and coronary collateral circulation in patients with stable coronary artery disease.

    PubMed

    Ballı, Mehmet; Çetin, Mustafa; Taşolar, Hakan; Uysal, Onur Kadir; Yılmaz, Mahmut; Durukan, Mine; Elbasan, Zafer; Çaylı, Murat

    2016-03-01

    Thyroid disease is a common endocrine disease with important effects on the cardiovascular system. As an adaptive response to myocardial ischemia, coronary collateral circulation (CCC) plays an important role in obstructive coronary artery disease (CAD). The association between serum thyroid hormone levels and development of CCC was investigated in the present study. In total, 430 consecutive patients who underwent coronary angiography procedure and had documented total occlusion in at least 1 major coronary artery were investigated retrospectively. Degree of CCC was classified according to Cohen-Rentrop method. Serum free triiodothyronine (FT3), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) were assessed by the chemiluminescence immunoassay technique. In spite of diabetes mellitus (p=0.019), smoking (p<0.001), and TSH (p<0.001), FT3 (p<0.001), FT4 (p=0.015), and subclinical hypothyroidism (SCH) (p<0.001) ratios were significantly different between groups. In regression analysis, SCH (p=0.024), DM (p=0.021), smoking (p<0.001), and heart failure (p=0.029) were independent predictors of poor CCC development in multivariate model 1. When regression analyses were performed based on multivariate model 2, TSH (p<0.001), FT3 (p<0.001), heart failure (p=0.022), smoking (p<0.001), and hyperlipidemia (HPL) (p=0.046) were independent predictors of poor CCC development. In addition to traditional risk factors, SCH, higher serum TSH, and lower FT3 levels were associated with development of poor CCC in patients with obstructive CA.

  1. P-wave dispersion and its relationship with the severity of the disease in patients with stable coronary artery disease

    PubMed Central

    Akin, Fatih; Firatli, Inci; Katkat, Fahrettin; Gurmen, Tevfik; Ayca, Burak; Kalyoncuoglu, Muhsin; Abaci, Okay; Sari, Mustafa; Ersanli, Murat; Kucukoglu, Serdar; Yigit, Zerrin

    2014-01-01

    OBJECTIVE: P- wave dispersion (PD) is an indicator of inhomogeneous and discontinuous propagation of sinus impulses. In the present study we aimed to investigate the PD and its association with the severity of the disease. in patients with stable coronary artery disease. METHODS: We prospectively analyzed 60 subjects with coronary artery disease (CAD) and 25 subjects with nor-mal coronary angiograms (control group). The maximum and minimum P-wave duration and PD were measured from the 12-lead surface electrocardiograms. The CAD severity was assessed by the severity score (Gensini score) and the number of vessels involved (vessel score). RESULTS: P max was longer in CAD group compared with the control group (p<0.001). PD was greater in the CAD group, compared with the control group (p<0.001). However, P min did not differ between the two groups. In bi-variate correlation, increased PD was correlated with presence of diabetes mellitus (r=0.316, p=0.014), smoking (r=0.348, p=0.006), left ventricular ejection fraction (r=-0.372, p=0.003), vessel score (r=0.848, p=0.001), and Gensini score (r=0.825, p=0.001). Multiple linear regression analysis showed that PD was independently associ¬ated with vessel score ((3=0.139, p=0.002) and Gensini score ((3=0.132, p=0.007). CONCLUSION: PD was greater in patients with CAD than in controls and it was associated with CAD severity. PMID:28058305

  2. Circulating sclerostin and Dickkopf-1 (DKK1) in predialysis chronic kidney disease (CKD): relationship with bone density and arterial stiffness.

    PubMed

    Thambiah, S; Roplekar, R; Manghat, P; Fogelman, I; Fraser, W D; Goldsmith, D; Hampson, Geeta

    2012-06-01

    Abnormalities of bone metabolism and increased vascular calcification are common in chronic kidney disease (CKD) and important causes of morbidity and mortality. The Wnt signaling pathway may play a role in the bone and vascular disturbances seen in CKD, termed collectively "CKD-MBD." The aim of the study was to investigate the possible association of circulating concentrations of the secreted Wnt signaling inhibitors DKK1 and sclerostin with BMD and arterial stiffness in predialysis CKD. Seventy-seven patients (48 M, 29 F), mean age 57 (SD = 14) years with CKD stages 3B (n = 32) and 4 (n = 45) were studied. Sclerostin, DKK1, PTH, and 1,25(OH)(2)D were analyzed. BMD was measured at the lumbar spine (LS), femoral neck (FN), total hip (TH), and forearm (FARM). Arterial stiffness index was determined by contour analysis of digital volume pulse (SI(DVP)). There was a positive correlation between sclerostin and age (r = 0.47, p < 0.000). Sclerostin was higher in men than women (p = 0.013). Following correction for age and gender, there was a negative association between GFR and sclerostin (p = 0.002). We observed a positive association between sclerostin and BMD at the LS (p = 0.0001), FN (p = 0.004), and TH (p = 0.002). In contrast, DKK1 was negatively associated with BMD at the FN (p = 0.038). A negative association was seen between DKK1 and SI(DVP) (p = 0.027). Our data suggest that the Wnt pathway may play a role in CKD-MBD. Prospective studies are required to establish the clinical relevance of sclerostin and DKK1 as serological markers in CKD.

  3. A new methodological approach to assess cardiac work by pressure-volume and stress-length relations in patients with aortic valve stenosis and dilated cardiomyopathy.

    PubMed

    Alter, P; Rupp, H; Rominger, M B; Klose, K J; Maisch, B

    2008-01-01

    In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived from cardiac volume and cardiac mass as assessed by cardiac magnetic resonance imaging (CMR) and invasively measured pressure. Left ventricular (LV) volume and myocardial mass were assessed in seven patients with aortic valve stenosis (AS), eight with dilated cardiomyopathy (DCM), and eight controls using electrocardiogram (ECG)-gated CMR. LV pressure was measured invasively. Pressure-volume curves were calculated based on ECG triggering. Stroke work was assessed as area within the pressure-volume loop. LV wall stress was calculated using a thick-wall sphere model. Similarly, stress-length loops were calculated to quantify stress-length-based work. Taking the LV geometry into account, the normalization with regard to ventricular circumference resulted in "myocardial work." Patients with AS (valve area 0.73+/-0.18 cm(2)) exhibited an increased LV myocardial mass when compared with controls (P<0.05). LV wall stress was increased in DCM but not in AS. Stroke work of AS was unchanged when compared with controls (0.539+/-0.272 vs 0.621+/-0.138 Nm, not significant), whereas DCM exhibited a significant depression (0.367+/-0.157 Nm, P<0.05). Myocardial work was significantly reduced in both AS and DCM when compared with controls (129.8+/-69.6, 200.6+/-80.1, 332.2+/-89.6 Nm/m(2), P<0.05), also after normalization (7.40+/-5.07, 6.27+/-3.20, 14.6+/-4.07 Nm/m(2), P<0.001). It is feasible to obtain LV pressure-volume and stress-length diagrams in patients based on the present novel methodological approach of using CMR and invasive pressure measurement. Myocardial work was reduced in patients with DCM and noteworthy

  4. Effects of critical coronary stenosis on global systolic left ventricular function quantified by pressure-volume relations during dobutamine stress in the canine heart.

    PubMed

    Steendijk, P; Baan, J; Van der Velde, E T; Baan, J

    1998-09-01

    In this study we quantified the effects of a critical coronary stenosis on global systolic function using pressure-volume relations at baseline and during incremental dobutamine stress. The effects of coronary stenosis have previously been analyzed mainly in terms of regional (dys)function. Global hemodynamics are generally considered normal until coronary flow is substantially reduced. However, pressure-volume analysis might reveal mechanisms not fully exposed by potentially load-dependent single-beat parameters. Moreover, no systematic analysis by pressure-volume relations of the effects of dobutamine over a wide dose range has previously been presented. In 14 dogs left ventricular volume and pressure were measured by conductance and micromanometer catheters, and left circumflex coronary flow by Doppler probes. Measurements in control and with left circumflex stenosis were performed at baseline and at five levels of dobutamine (2.5 to 20 microg/kg/min). The end-systolic pressure-volume relation (ESPVR) dP/dtMAX vs. end-diastolic volume (dP/dtMAX - V(ED)) and the relation between stroke work and end-diastolic volume (preload recruitable stroke work [PRSW]) were derived from data obtained during gradual caval occlusion. In control, dobutamine gradually increased heart rate up to 20 microg/kg/min, the inotropic effect blunted at 15 microg/kg/min. With stenosis, the chronotropic effect was similar, however, contractile state was optimal at approximately 10 microg/kg/min and tended to go down at higher levels. At baseline, the positions of ESPVR and PRSW, but not of dP/dtMAX - V(ED), showed a significant decrease in function with stenosis. No differences between control and stenosis were present at 2.5 microg/kg/min; the differences were largest at 15 microg/kg/min. Pressure-volume relations and incremental dobutamine may be used to quantify the effects of critical coronary stenosis. The positions of these relations are more consistent and more useful indices than the

  5. Assessment of renal artery stenosis using both resting pressures ratio and fractional flow reserve: relationship to angiography and ultrasonography.

    PubMed

    Kadziela, Jacek; Witkowski, Adam; Januszewicz, Andrzej; Cedro, Krzysztof; Michałowska, Ilona; Januszewicz, Magdalena; Kabat, Marek; Prejbisz, Aleksander; Kalińczuk, Lukasz; Zieleń, Piotr; Michel-Rowicka, Katarzyna; Warchoł, Ewa; Rużyłło, Witold

    2011-08-01

    BACKGROUND. Clinical benefit from renal artery revascularization remains controversial, probably because of inaccurate stenosis severity assessment. Objective. The aim of the study was to evaluate resting translesional pressures ratio and renal fractional flow reserve (rFFR) in relation to angiography and Doppler duplex ultrasonography in patients with at least moderate renal artery stenosis (RAS). METHODS. 44 hypertensive patients (48% of males, mean age 65 years) with at least moderate RAS were investigated. Translesional systolic pressure gradient (TSPG), resting Pd/Pa ratio (the ratio of mean distal to lesion and mean proximal pressures) and hyperemic rFFR - after intrarenal administration of papaverine - were evaluated. Quantitative angiographic analysis of stenosis severity was performed including minimal lumen diameter (MLD) and percent diameter stenosis (DS) assessment. Renal/aortic ratio (RAR), resistive index (RI) and deltaRI (side-to side difference) were obtained in Doppler-duplex ultrasonography. The predictive value of selected variables was calculated using receiver-operating characteristics curves. RESULTS. Mean Pd/Pa ratio was 0.86 ± 0.12 and decreased to 0.79 ± 0.13 after papaverine administration. Both Pd/Pa ratio and rFFR strongly correlated with TSPG (r = -0.92, p < 0.0001 and r = -0.88, p < 0.0001, respectively) and moderately with MLD (r = 0.62, p < 0.0001 and r = 0.66, p < 0.0001) and DS (r = -0.63, p < 0.0001 and r = -0.70, p < 0.0001). To identify more than 70% RAS, considered severe, the most predictive cut-off values were 0.93 for Pd/Pa ratio and 0.80 for rFFR. CONCLUSIONS. Mean Pd/Pa ratio and rFFR strongly correlated with angiographic data and in less pronounced manner with ultrasound parameters reflecting intrarenal blood flow. The best accuracy cut-off points for severe RAS predicting were 0.93 and 0.80, respectively.

  6. A Longitudinal Relationship Between Depressive Symptoms and Development of Metabolic Syndrome: The Coronary Artery Risk Development in Young Adults Study.

    PubMed

    Womack, Veronica Y; De Chavez, Peter John; Albrecht, Sandra S; Durant, Nefertiti; Loucks, Eric B; Puterman, Eli; Redmond, Nicole; Siddique, Juned; Williams, David R; Carnethon, Mercedes R

    2016-09-01

    Despite variability in the burden of elevated depressive symptoms by sex and race and differences in the incidence of metabolic syndrome, few prior studies describe the longitudinal association of depressive symptoms with metabolic syndrome in a diverse cohort. We tested whether baseline and time-varying depressive symptoms were associated with metabolic syndrome incidence in black and white men and women from the Coronary Artery Risk Development in Young Adults study. Participants reported depressive symptoms using the Center for Epidemiologic Studies Depression Scale at four examinations between 1995 and 2010. At those same examinations, metabolic syndrome was determined. Cox proportional hazards models were used to examine the associations of depressive symptoms on the development of metabolic syndrome in 3208 participants without metabolic syndrome at baseline. For 15 years, the incidence rate of metabolic syndrome (per 10,000 person-years) varied by race and sex, with the highest rate in black women (279.2), followed by white men (241.9), black men (204.4), and white women (125.3). Depressive symptoms (per standard deviation higher) were associated with incident metabolic syndrome in white men (hazard ratio = 1.25, 95% confidence interval = 1.08-1.45) and white women (hazard ratio = 1.17, 95% confidence interval = 1.00-1.37) after adjustment for demographic characteristics and health behaviors. There was no significant association between depression and metabolic syndrome among black men or black women. Higher depressive symptoms contribute modestly to the onset of metabolic syndrome among white adults.

  7. Relationship between non-invasive haemodynamic responses and cardiopulmonary exercise testing in patients with coronary artery disease.

    PubMed

    Sperling, Milena Pelosi Rizk; Caruso, Flávia Cristina Rossi; Mendes, Renata Gonçalves; Dutra, Daniela Bassi; Arakelian, Vivian Maria; Bonjorno, José Carlos; Catai, Aparecida Maria; Arena, Ross; Borghi-Silva, Audrey

    2016-03-01

    Non-invasive assessment of haemodynamic function by impedance cardiography (IC) constitutes an interesting approach to monitor cardiac function in patients with coronary artery disease (CAD). However, such measurements are most often performed at rest, whereas symptoms are also possible during exertion, particularly at higher intensities. In addition, the association between IC during exertion and cardiopulmonary exercise testing (CPX) is not well understood in these patients, which was the aim of this study. Nineteen men (age = 62 ± 6 years) with CAD [left ventricular ejection fraction (LVEF) = 61 ± 10%] underwent a CPX using an incremental protocol on a cycle ergometer, with simultaneous measurement of IC. Cardiac output (CO), stroke volume (SV), cardiac index (CI), peak oxygen consumption (VO2 ), the oxygen uptake efficiency slope (OUES), circulatory power and ventilatory power were determined. Pearson product-moment correlation analysis revealed peak VO2 (r = 0·46) was significantly related to CO. Peak oxygen pulse (0·52) was associated with SV. OUES was associated with resting SV (0·47) and with peak SV (r = 0·52). These findings suggest that IC indices are associated with certain, but not all, established CPX measures in patients with stable CAD. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  8. A log-linearized arterial viscoelastic model for evaluation of the carotid artery.

    PubMed

    Hirano, Harutoyo; Horiuchi, Tetsuya; Kutluk, Abdugheni; Kurita, Yuichi; Ukawa, Teiji; Nakamura, Ryuji; Saeki, Noboru; Higashi, Yukihito; Kawamoto, Masashi; Yoshizumi, Masao; Tsuji, Toshio

    2013-01-01

    This paper proposes a method for qualitatively estimating the mechanical properties of arterial walls on a beat-to-beat basis through noninvasive measurement of continuous arterial pressure and arterial diameter using an ultrasonic device. First, in order to describe the nonlinear relationships linking arterial pressure waveforms and arterial diameter waveforms as well as the viscoelastic characteristics of arteries, we developed a second-order nonlinear model (called the log-linearized arterial viscoelastic model) to allow estimation of arterial wall viscoelasticity. Next, to verify the validity of the proposed method, the viscoelastic indices of the carotid artery were estimated. The results showed that the proposed model can be used to accurately approximate the mechanical properties of arterial walls. It was therefore deemed suitable for qualitative evaluation of arterial viscoelastic properties based on noninvasive measurement of arterial pressure and arterial diameter.

  9. Quantitative relationship between coronary artery calcium score and hyperemic myocardial blood flow as assessed by hybrid 15O-water PET/CT imaging in patients evaluated for coronary artery disease.

    PubMed

    Danad, Ibrahim; Raijmakers, Pieter G; Appelman, Yolande E; Harms, Hendrik J; de Haan, Stefan; Marques, Koen M; van Kuijk, Cornelis; Allaart, Cornelis P; Hoekstra, Otto S; Lammertsma, Adriaan A; Lubberink, Mark; van Rossum, Albert C; Knaapen, Paul

    2012-04-01

    The incremental value of CAC over traditional risk factors to predict coronary vasodilator dysfunction and inherent myocardial blood flow (MBF) impairment is only scarcely documented (MBF). The aim of this study was therefore to evaluate the relationship between CAC content, hyperemic MBF, and coronary flow reserve (CFR) in patients undergoing hybrid (15)O-water PET/CT imaging. We evaluated 173 (mean age 56 ± 10, 78 men) patients with a low to intermediate likelihood for coronary artery disease (CAD), without a documented history of CAD, undergoing vasodilator stress (15)O-water PET/CT and CAC scoring. Obstructive coronary artery disease was excluded by means of invasive (n = 44) or CT-based coronary angiography (n = 129). 91 of 173 patients (52%) had a CAC score of zero. Of those with CAC, the CAC score was 0.1-99.9, 100-399.9, and ≥400 in 31%, 12%, and 5% of patients, respectively. Global CAC score showed significant inverse correlation with hyperemic MBF (r = -0.32, P < .001). With increasing CAC score, there was a decline in hyperemic MBF on a per-patient basis [3.70, 3.30, 2.68, and 2.53 mL · min(-1) · g(-1), with total CAC score of 0, 0.1-99.9, 100-399.9, and ≥400, respectively (P < .001)]. CFR showed a stepwise decline with increasing levels of CAC (3.70, 3.32, 2.94, and 2.93, P < .05). Multivariate analysis, including age, BMI, and CAD risk factors, revealed that only age, male gender, BMI, and hypercholesterolemia were associated with reduced stress perfusion. Furthermore, only diabetes and age were independently associated with CFR. In patients without significant obstructive CAD, a greater CAC burden is associated with a decreased hyperemic MBF and CFR. However, this association disappeared after adjustment for traditional CAD risk factors. These results suggest that CAC does not add incremental value regarding hyperemic MBF and CFR over established CAD risk factors in patients without obstructive CAD.

  10. Relationship between visible branch arteries distal to the stenosis on magnetic resonance angiography and stroke recurrence in patients with severe middle cerebral artery trunk stenosis: a one-year follow up study.

    PubMed

    Chen, Hongbing; Li, Zhuhao; Hong, Hua; Xing, Shihui; Liu, Gang; Zhang, Aiwu; Tan, Shuangquan; Zhang, Jian; Zeng, Jinsheng

    2015-09-16

    To evaluate the relationship between the flow signal intensity of branch arteries distal to the stenosis on 3-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and the risk of stroke recurrence in patients with severe middle cerebral artery (MCA) trunk stenosis. We prospectively recruited 153 patients (mean age 62.9 ± 13.0 years, 106 males) with a first ischemic stroke or transient ischemic attack caused by a severe MCA trunk stenosis (70 % to 99 %) confirmed by 3D TOF MRA and followed them for one year to determine the stroke recurrence. The MCA branch signal intensity distal to the site of stenosis on 3D TOF MRA was classified as either good (grade A) or poor [mild reduction (grade B) or severe reduction (grade C)] according to the extent to which the MCA could be visualized. The patients were divided into groups A (35), B (58), or C (60) based on the MRA grading of the MCA branch signal intensity distal to the site of stenosis. Poor MCA branch signal intensity was associated with internal border-zone infarction (p < 0.05). The risk of stroke recurrence in the ipsilateral MCA in the first year was 18.3 %. The 1-year cumulative incidence of recurrence was higher in the patients in group C (30 %) than in groups B (12.1 %) or A (8.6 %) (Log rank, p = 0.007). Multivariate analyses via Cox proportional hazard regression demonstrated that only a grade C classification of the signal intensity of the MCA branches was an independent predictor of stroke recurrence in the ipsilateral MCA (hazard ratio = 3.0, 95 % confidence interval = 1.3-7.4, p = 0.014). This study demonstrated that MCA branch signal intensity as assessed via 3D TOF MRA may be a useful and simple tool to stratify the risk of stroke recurrence in patients with severe MCA trunk stenosis.

  11. Conduit artery structure and function in lowlanders and native highlanders: relationships with oxidative stress and role of sympathoexcitation

    PubMed Central

    Lewis, Nia C S; Bailey, Damian M; duManoir, Gregory R; Messinger, Laura; Lucas, Samuel J E; Cotter, James D; Donnelly, Joseph; McEneny, Jane; Young, Ian S; Stembridge, Mike; Burgess, Keith R; Basnet, Aparna S; Ainslie, Philip N

    2014-01-01

    Research detailing the normal vascular adaptions to high altitude is minimal and often confounded by pathology (e.g. chronic mountain sickness) and methodological issues. We examined vascular function and structure in: (1) healthy lowlanders during acute hypoxia and prolonged (∼2 weeks) exposure to high altitude, and (2) high-altitude natives at 5050 m (highlanders). In 12 healthy lowlanders (aged 32 ± 7 years) and 12 highlanders (Sherpa; 33 ± 14 years) we assessed brachial endothelium-dependent flow-mediated dilatation (FMD), endothelium-independent dilatation (via glyceryl trinitrate; GTN), common carotid intima–media thickness (CIMT) and diameter (ultrasound), and arterial stiffness via pulse wave velocity (PWV; applanation tonometry). Cephalic venous biomarkers of free radical-mediated lipid peroxidation (lipid hydroperoxides, LOOH), nitrite (NO2–) and lipid soluble antioxidants were also obtained at rest. In lowlanders, measurements were performed at sea level (334 m) and between days 3–4 (acute high altitude) and 12–14 (chronic high altitude) following arrival to 5050 m. Highlanders were assessed once at 5050 m. Compared with sea level, acute high altitude reduced lowlanders’ FMD (7.9 ± 0.4 vs. 6.8 ± 0.4%; P = 0.004) and GTN-induced dilatation (16.6 ± 0.9 vs. 14.5 ± 0.8%; P = 0.006), and raised central PWV (6.0 ± 0.2 vs. 6.6 ± 0.3 m s−1; P = 0.001). These changes persisted at days 12–14, and after allometrically scaling FMD to adjust for altered baseline diameter. Compared to lowlanders at sea level and high altitude, highlanders had a lower carotid wall:lumen ratio (∼19%, P ≤ 0.04), attributable to a narrower CIMT and wider lumen. Although both LOOH and NO2– increased with high altitude in lowlanders, only LOOH correlated with the reduction in GTN-induced dilatation evident during acute (n = 11, r = −0.53) and chronic (n = 7, r = −0.69; P

  12. Conduit artery structure and function in lowlanders and native highlanders: relationships with oxidative stress and role of sympathoexcitation.

    PubMed

    Lewis, Nia C S; Bailey, Damian M; Dumanoir, Gregory R; Messinger, Laura; Lucas, Samuel J E; Cotter, James D; Donnelly, Joseph; McEneny, Jane; Young, Ian S; Stembridge, Mike; Burgess, Keith R; Basnet, Aparna S; Ainslie, Philip N

    2014-03-01

    Research detailing the normal vascular adaptions to high altitude is minimal and often confounded by pathology (e.g., chronic mountain sickness) and methodological issues. We examined vascular function and structure in: (1) healthy lowlanders during acute hypoxia and prolonged (∼2 weeks) exposure to high altitude, and (2) high-altitude natives at 5050 m (highlanders). In 12 healthy lowlanders (aged 32 ± 7 years) and 12 highlanders (Sherpa; 33 ± 14 years) we assessed brachial endothelium-dependent flow-mediated dilatation (FMD), endothelium-independent dilatation (via glyceryl trinitrate; GTN), common carotid intima-media thickness (CIMT) and diameter (ultrasound), and arterial stiffness via pulse wave velocity (PWV; applanation tonometry). Cephalic venous biomarkers of free radical-mediated lipid peroxidation (lipid hydroperoxides, LOOH), nitrite (NO2-) and lipid soluble antioxidants were also obtained at rest. In lowlanders, measurements were performed at sea level (334 m) and between days 3-4 (acute high altitude) and 12-14 (chronic high altitude) following arrival to 5050 m. Highlanders were assessed once at 5050 m. Compared with sea level, acute high altitude reduced lowlanders' FMD (7.9 ± 0.4 vs. 6.8 ± 0.4%; P = 0.004) and GTN-induced dilatation (16.6 ± 0.9 vs. 14.5 ± 0.8%; P = 0.006), and raised central PWV (6.0 ± 0.2 vs. 6.6 ± 0.3 m s(-1); P = 0.001). These changes persisted at days 12-14, and after allometrically scaling FMD to adjust for altered baseline diameter. Compared to lowlanders at sea level and high altitude, highlanders had a lower carotid wall:lumen ratio (∼19%, P ≤ 0.04), attributable to a narrower CIMT and wider lumen. Although both LOOH and NO2- increased with high altitude in lowlanders, only LOOH correlated with the reduction in GTN-induced dilatation evident during acute (n = 11, r = -0.53) and chronic (n = 7, r = -0.69; P ≤ 0.01) exposure to 5050 m. In a follow-up, placebo-controlled experiment (n = 11 healthy lowlanders

  13. The Influence of Tobacco Smoking on the Relationship between Pressure and Flow in the Middle Cerebral Artery in Humans

    PubMed Central

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

    2013-01-01

    Background 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). Methods 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). Results 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. Conclusions 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. PMID:23977332

  14. Arterial waveform parameters in a large, population-based sample of adults: relationships with ethnicity and lifestyle factors.

    PubMed

    Sluyter, J D; Hughes, A D; Thom, S A McG; Lowe, A; Camargo, C A; Hametner, B; Wassertheurer, S; Parker, K H; Scragg, R K R

    2016-12-22

    Little is known about how aortic waveform parameters vary with ethnicity and lifestyle factors. We investigated these issues in a large, population-based sample. We carried out a cross-sectional analysis of 4798 men and women, aged 50-84 years from Auckland, New Zealand. Participants were 3961 European, 321 Pacific, 266 Maori and 250 South Asian people. We assessed modifiable lifestyle factors via questionnaires, and measured body mass index (BMI) and brachial blood pressure (BP). Suprasystolic oscillometry was used to derive aortic pressure, from which several haemodynamic parameters were calculated. Heavy alcohol consumption and BMI were positively related to most waveform parameters. Current smokers had higher levels of aortic augmentation index than non-smokers (difference=3.7%, P<0.0001). Aortic waveform parameters, controlling for demographics, antihypertensives, diabetes and cardiovascular disease (CVD), were higher in non-Europeans than in Europeans. Further adjustment for brachial BP or lifestyle factors (particularly BMI) reduced many differences but several remained. Despite even further adjustment for mean arterial pressure, pulse rate, height and total:high-density lipoprotein cholesterol, compared with Europeans, South Asians had higher levels of all measured aortic waveform parameters (for example, for backward pressure amplitude: β=1.5 mm Hg; P<0.0001), whereas Pacific people had 9% higher loge (excess pressure integral) (P<0.0001). In conclusion, aortic waveform parameters varied with ethnicity in line with the greater prevalence of CVD among non-white populations. Generally, this was true even after accounting for brachial BP, suggesting that waveform parameters may have increased usefulness in capturing ethnic variations in cardiovascular risk. Heavy alcohol consumption, smoking and especially BMI may partially contribute to elevated levels of these parameters.Journal of Human Hypertension advance online publication, 22 December 2016; doi:10

  15. Quantification of carotid artery plaque stability with multiple region of interest based ultrasound strain indices and relationship with cognition

    NASA Astrophysics Data System (ADS)

    Meshram, N. H.; Varghese, T.; Mitchell, C. C.; Jackson, D. C.; Wilbrand, S. M.; Hermann, B. P.; Dempsey, R. J.

    2017-08-01

    Vulnerability and instability in carotid artery plaque has been assessed based on strain variations using noninvasive ultrasound imaging. We previously demonstrated that carotid plaques with higher strain indices in a region of interest (ROI) correlated to patients with lower cognition, probably due to cerebrovascular emboli arising from these unstable plaques. This work attempts to characterize the strain distribution throughout the entire plaque region instead of being restricted to a single localized ROI. Multiple ROIs are selected within the entire plaque region, based on thresholds determined by the maximum and average strains in the entire plaque, enabling generation of additional relevant strain indices. Ultrasound strain imaging of carotid plaques, was performed on 60 human patients using an 18L6 transducer coupled to a Siemens Acuson S2000 system to acquire radiofrequency data over several cardiac cycles. Patients also underwent a battery of neuropsychological tests under a protocol based on National Institute of Neurological Disorders and Stroke and Canadian Stroke Network guidelines. Correlation of strain indices with composite cognitive index of executive function revealed a negative association relating high strain to poor cognition. Patients grouped into high and low cognition groups were then classified using these additional strain indices. One of our newer indices, namely the average L  -  1 norm with plaque (AL1NWP) presented with significantly improved correlation with executive function when compared to our previously reported maximum accumulated strain indices. An optimal combination of three of the new indices generated classifiers of patient cognition with an area under the curve (AUC) of 0.880, 0.921 and 0.905 for all (n  =  60), symptomatic (n  =  33) and asymptomatic patients (n  =  27) whereas classifiers using maximum accumulated strain indices alone provided AUC values of 0.817, 0.815 and 0

  16. Relationship between white matter hyperintensities volume and the circle of Willis configurations in patients with carotid artery pathology.

    PubMed

    Saba, Luca; Sanfilippo, Roberto; Porcu, Michele; Lucatelli, Pierleone; Montisci, Roberto; Zaccagna, Fulvio; Suri, Jasjit; Anzidei, Michele; Wintermark, Max

    2017-04-01

    We aimed to assess if there is a difference of distribution and volume of white matter hyperintensities (WMH) in the brain according to the Circle of Willis (CoW) configuration in patients with carotid artery pathology. One-hundred consecutive patients (79 males, 21 females; mean age 70 years; age range 46-84 years) that underwent brain MRI before carotid endarterectomy (CEA) were included. FLAIR-WMH lesion volume was performed using a semi-automated segmentation technique and the status of the circle of Willis was assessed by two neuroradiologists in consensus. We found a prevalence of 55% of variants in the CoW configuration; 22 cases had one variants (40%); 25 cases had two variants (45.45%) and 8 cases showed 3 variants (14.55%). The configuration that was associated with the biggest WMH volume and number of lesions was the A1+PcoA+PcoA. The PcoA variants were the most prevalent and there was no statistically significant difference in number of lesions and WMH for each vascular territory assessed and the same results were found for AcoA and A1 variants. Results of our study suggest that the more common CoW variants are not associated with the presence of an increased WMH or number of lesions whereas uncommon configurations, in particular when 2 or more segment are missing increase the WMH volume and number of lesions. The WHM volume of the MCA territory seems to be more affected by the CoW configuration. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The effect of C1 bursting fracture on comparative anatomical relationship between the internal carotid artery and the atlas.

    PubMed

    Kim, Moon Seok; Kim, Jun Young; Kim, Il Sup; Cho, Kyoung Seok; Kim, Sang Don; Lee, Ho Jin; Kim, Jong Tae; Hong, Jae Taek

    2016-01-01

    To describe the effect of the C1 bursting fracture on the location of the internal carotid artery (ICA) around the atlas. The authors analyzed the morphology of the atlas and the ICA in 15 patients with C1 bursting fracture and compared with control group (77 patients) without any pathology. All patients were evaluated with CT angiography for the anatomical assessment. The laterality of the ICA, the distances of the ICA from the midline, anterior tubercle, and ventral surface of the C1 lateral mass were compared between two groups. The distance between the lateral margin of the longus capitis muscle and the inner edge of the transverse foramen was also measured. Medially located ICA was more common in the C1 bursting fracture group than control group (76.7 vs 42.8 %). There were no significant differences between 2 groups for the distance from the midline, anterior tubercle, and ventral surface of the C1 lateral mass, respectively. The distance of the longus capitis muscle to transverse foramen was 2.52 ± 2.09 and 4.15 ± 3.09 mm in each group, and there was statistically significant difference (p < 0.01). Lateral displacement of the bony structure of C1 bursting fracture changes the relative location of the ICA medially, which increase the injury risk during the bicortical C1 screw insertion. These data suggest that CT angiography or enhanced CT scans can give critical information to choose the ideal fixation technique and the proper trajectory of the screws for C1 bursting fracture.

  18. Relationships between the lung-heart ratio assessed from post-exercise thallium-201 myocardial tomograms, myocardial ischemia and the extent of coronary artery disease

    SciTech Connect

    Ilmer, B.; Reijs, A.E.; Reiber, J.H.; Bakker, W.; Fioretti, P. )

    1990-01-01

    Uptake of thallium (Tl)-201 in the lungs has been proposed as a measure of left ventricular dysfunction. In this study we were interested in pursuing two goals: (1) to assess possible relationships between the post-exercise Tl-201 lung-heart (LH)-ratio determined from the anterior view during SPECT-acquisition, myocardial ischemia and the extent of coronary artery disease; and (2) to explore the effects of coronary revascularisation procedures on the LH-ratio. The study group consisted of 145 patients with early and late postexercise Tl-201 tomograms, including 32 PTCA-patients with pre- and post-PTCA studies and 20 patients who underwent coronary artery bypass surgery (CABG) with corresponding pre- and post-CABG studies. Ischemia was defined as evoked angina during the exercise test in combination with greater than or equal to 1 mm horizontal or downsloping ST-depression on the ECG. The severity of coronary obstructions was assessed from coronary angiograms with a PC-based digital caliper technique; a stenosis was defined to be significant when its severity exceeded 50% diameter stenosis. The LH-ratio was defined by the ratio of the mean pulmonary counts and the mean myocardial counts assessed from corresponding regions of interest (ROI's) positioned over the left lung and the heart, respectively in the anterior view of a tomographic data acquisition procedure. Our results made clear that the LH-ratio was not significantly different between patients with and without ischemia during exercise, and between patients with single vs. multiple vessel disease.

  19. Tricuspid annular plane systolic excursion and pulmonary arterial systolic pressure relationship in heart failure: an index of right ventricular contractile function and prognosis.

    PubMed

    Guazzi, M; Bandera, F; Pelissero, G; Castelvecchio, S; Menicanti, L; Ghio, S; Temporelli, P L; Arena, R

    2013-11-01

    Echo-derived pulmonary arterial systolic pressure (PASP) and right ventricular (RV) tricuspid annular plane systolic excursion (TAPSE; from the end of diastole to end-systole) are of basic relevance in the clinical follow-up of heart failure (HF) patients, carrying two- to threefold increase in cardiac risk when increased and reduced, respectively. We hypothesized that the relationship between TAPSE (longitudinal RV fiber shortening) and PASP (force generated by the RV) provides an index of in vivo RV length-force relationship, with their ratio better disclosing prognosis. Two hundred ninety-three HF patients with reduced (HFrEF, n = 247) or with preserved left ventricular (LV) ejection fraction (HFpEF, n = 46) underwent echo-Doppler studies and N-terminal pro-brain-type natriuretic peptide assessment and were tracked for adverse events. The median follow-up duration was 20.8 mo. TAPSE vs. PASP relationship showed a downward regression line shift in nonsurvivors who were more frequently presenting with higher PASP and lower TAPSE. HFrEF and HFpEF patients exhibited a similar distribution along the regression line. Given the TAPSE, PASP, and TAPSE-to-PASP ratio (TAPSE/PASP) collinearity, separate Cox regression and Kaplan-Meier analyses were performed: one with TAPSE and PASP as individual measures, and the other combining them in ratio form. Hazard ratios for variables retained in the multivariate regression were as follows: TAPSE/PASP relationship is shifted downward in nonsurvivors with a similar distribution in HFrEF and HFpEF, and their ratio improves prognostic resolution. The TAPSE vs. PASP relationship as a possible index of the length-force relationship may be a step forward for a more efficient RV function evaluation and

  20. [Relationship between estimated glomerular filtration rate level and clinical characteristics and outcome in patients with angiographic coronary artery disease and normal serum creatinine].

    PubMed

    Li, Quan; Gao, Yue-chun; He, Ji-qiang; Jiang, Teng-yong; Ren, Xue-jun; Chen, Fang

    2013-07-01

    To explore the relationship between estimated glomerular filtration rate level and clinical characteristics and outcome in coronary artery disease (CAD) patients with normal serum creatinine. A total of 548 hospitalized and angiographic CAD patients with normal fasting serum creatinine were enrolled. The kidney function was estimated by using the abbreviated modification of diet in renal disease (MDRD) study equation. Patients were divided into three groups according to eGFR tertiles: high eGFR group (eGFR > 88.15 ml×min(-1)×1.73 m(-2), n = 184); intermediate group ZU(70.30 ml× min(-1)×1.73 m(-2) < eGFR ≤ 88.15 ml×min(-1)×1.73 m(-2), n = 187); low eGFR group (eGFR ≤ 70.30 ml × min(-1)×1.73 m(-2), n = 177). Clinical data and cardiovascular risk factors were recorded after admission and during (14.02 ± 8.31) months follow up. The primary end point was combined major adverse cardiovascular and cerebral events (MACCE) including death, targeted vascular revascularization, non-fatal myocardial infarction, rehospitalization due to unstable angina and heart failure, and transient ischemic attack (TIA) and stroke. Patients in intermediate and low eGFR groups were older, more males, had more severe coronary artery disease, higher level of hsCRP, higher incidence of hypertension, and lower smoking rate than those in high eGFR group (all P < 0.05). A total of 89 MACCE were recorded during follow up. The level of eGFR was significantly lower in patients with MACCE than patients without MACCE [(73.76 ± 19.81) ml×min(-1)×1.73 m(-2) vs. (84.97 ± 23.42) ml×min(-1)×1.73 m(-2), P < 0.05]. Univariate and multivariate Cox regression analysis showed that eGFR was an independent predictor of MACCE in patients with CAD (univariate analysis: RR = 0.99, 95%CI:0.973-0.997, P < 0.05; multivariate analysis: RR = 0.98, 95%CI:0.976-0.998, P < 0.05). Kaplan-Meier survival analysis suggested that patients with low eGFR was linked with a decreased event free survival ratio (log

  1. The relationship between preoperative serum cortisol level and the stability of plaque in carotid artery stenosis patients undergoing carotid endarterectomy.

    PubMed

    Qin, Feng; Sun, Yudong; Hu, Wenping; Wei, Xiaolong; Li, Zhenjiang; Zhou, Jian; Zhao, Zhiqing; Jing, Zaiping

    2016-07-01

    Stability of plaque has been implicated as risk factor for stroke. Serum cortisol regulates lipoprotein metabolism and immune response, contributing to plaque stability in atherosclerosis. However, the relationship between serum cortisol and stability of carotid plaque has not been well characterized. We conducted a serology analysis to identify the relationship between serum cortisol and carotid plaque stability. Between May 2013 to October 2015, 73 patients with carotid stenosis patients undergoing carotid endarterectomy (CEA) were enrolled in our study. Serum cortisol was analyzed at 8:00 AM in the morning before surgery via liquid chromatography tandem mass spectrometry. According to the classification made by the American Heart Association, hematoxylin-and-eosin staining was performed to divide these patients into either a stable or unstable group, according to the morphology of fibrous cap, lipid core and intima layer. A curve fitting method was used to identify the relationship between preoperative serum cortisol and stability of carotid plaque. Univariate and multivariate logistic regression analysis were used to identify carotid plaque stability-associated serum cortisol. Curve fitting's result represents a U-shape characteristic. A total of 314.92 and 395.23 nmol/L were considered as the cut point for preoperative serum cortisol when trisected the patients. When adjusted for degree of stenosis, hyperlipemia, smoking and low-density lipoprotein (LDL), univariate and multivariate logistic regression analysis' results demonstrated that preoperative serum cortisol can significantly affect carotid plaque stability. The odds ratio values in multivariate logistic regression analysis for C reactive protein (CRP), white blood cell (WBC), interleukin-6 (IL-6) and preoperative serum cortisol level were 7.67 and 20.86 respectively. Preoperative serum cortisol was associated with stability of carotid plaque in patients undergoing CEA. Low or high levels of

  2. The Relationship Between Decelerations with Late Components in the Second Stage of Labor and Umbilical Cord Artery PH

    DTIC Science & Technology

    1993-01-01

    oxygen and/or oxytocin , and the methods of fetal monitoring are presented. The length of the second stage of labor ranged from the shortest at 10...probably not a contributing factor to the pH differences. The mean length of labor was actually shorter in the lower pH group. Oxygen and oxytocin use...SUBTITLE 1. FUNDING NUMBERS S. FUNDING NUMBERS The Relationship Between Decelerations with Late Components in the Second Stage of Labor and TTnhi ] •,-j Cn

  3. [Digital subtract arteriographic characteristics of carotid artery, vertebral artery, subclavian artery and renal artery in type 2 diabetic patients with lower extremities peripheral arterial disease].

    PubMed

    Chen, Da-Wei; Lu, Wu-Sheng; Wang, Chun; Jiao, He; Tian, Hao-Ming; Ran, Xing-Wu

    2012-09-01

    To investigate angiographical characteristics of carotid, vertebral, subclavian, and renal arteries in the type 2 diabetic patients with lower extremities peripheral arterial disease (LEPAD). There were 104 type 2 diabetic patients with LEPAD recruited in this study, who received digital subtract arteriography (DSA). Ankle-brachial index (ABI) assessment was also performed in 50 participants. Dependent upon the stenosis degree of vertebral artery, subclavian artery and renal artery measured by DSA, the patients were divided into normal group (stenosis < or = 50%) or pathological group(stenosis > 50% or blocked lesions). The angiographic features of carotid, vertebral, subclavian, and renal arteries were analyzed and the relationship between arterial stenosis and ABI was explored. DSA results of 104 patients showed that the most common lesion in the arteries was plaque. The stenosis degrees of 51%-74% and 75%-99% were most commonly observed in renal artery, with incidence of 22.1% and 5.8%, respectively. Arterial occlusion was most commonly observed in vertebral artery, with incidence of 27.9%. The patients with stenosis or occlusion of arteries had lower ABI (P = 0.000), and the patients with stenosis or occlusion of vertebral and renal arteries also had lower ABI (P = 0.003 and 0.02, respectively), compared with those without stenosis. ABI < 0.9 indicated higher risk of stenosis or occlusion of vertebral and renal arteries (P = 0.008 and 0.047 respectively). Between the patients with subclavian arterial stenosis and those without this artery stenosis, there was no statistical significant difference observed in ABI level. Type 2 diabetic patients with LEPAD can affect multiple arteries, showing plaque formation, multi-segmental stenosis and occlusion of arteries. The patients with ABI < 0.9 have higher risk of multiple arterial stenosis or occlusion lesions.

  4. Relationship between diffusion tensor fractional anisotropy and long-term motor outcome in patients with hemiparesis after middle cerebral artery infarction.

    PubMed

    Koyama, Tetsuo; Marumoto, Kohei; Miyake, Hiroji; Domen, Kazuhisa

    2014-10-01

    Magnetic resonance diffusion tensor fractional anisotropy (DTI-FA) is often used to characterize neural damage after stroke. Here we assessed the relationship between DTI-FA and long-term motor outcome in patients after middle cerebral artery (MCA) infarction. Fractional anisotropy (FA) maps were generated from diffusion tensor brain images obtained from 16 patients 14-18 days postinfarction, and tract-based spatial statistics (TBSS) analysis was applied. Regions of interest were set within the right and left corticospinal tracts, and mean FA values were extracted from individual TBSS data. Hemiparesis motor outcome was evaluated according to Brunnstrom stage (BRS: 1-6, severe-normal) for separate shoulder/elbow/forearm, hand, and lower extremity functions, as well as the motor component score of the Functional Independence Measure (FIM-motor: 13-91, null-full) 5-7 months after onset. Ratios between FA values in the affected and unaffected hemispheres (rFA) were assessed by BRS and FIM-motor scores. rFA values were .636-.984 (median, .883) and BRS scores were 1-6 (median, 3) for shoulder/elbow/forearm, 2-6 (median, 3) for hand, and 3-6 (median, 5) for the lower extremities. FIM-motor scores were 51-90 (median, 75). Analysis revealed significant relationships between rFA and BRS data (correlation coefficient: .687 for shoulder/elbow/forearm, .579 for hand, and .623 for lower extremities) but no significance relationship between rFA and FIM-motor scores. The results suggest that DTI-FA is applicable for predicting the long-term outcome of extremity functions after MCA infarction. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  5. [Relationship between the alveolar-arterial oxygen gradient and PaO₂/FiO₂-introducing PEEP into the model].

    PubMed

    Sánchez Casado, M; Quintana Díaz, M; Palacios, D; Hortigüela, V; Marco Schulke, C; García, J; Canabal, A; Pérez Pedrero, M J; Velasco Ramos, A; Arrese, M A

    2012-01-01

    To determine whether the alveolar-arterial oxygen gradient (Grad[A-a]O₂) helps confirm the influence of PEEP on PaFi (PaO₂/FiO₂). Observational study; we used linear regression to perform a multivariate study to improve the PaFi formula by taking PEEP into account. Tertiary hospital. We included all patients who were admitted to the intensive care unit, regardless of pulmonary damage. We recorded personal history, clinical judgment, intensive care data, severity scores on the first day and progression. Two calculated variables: PaFi and Grad(A-a)O₂. A total of 956 patients were included: 63.9% men; median age 68 years. On the first day, 31.8% did not have mechanical ventilation (MV), 13.1% had non-invasive MV and 55.1% had invasive MV. PaFi values: 32.9% 0-200, 32.2% 201-300, and 34.8% >300. PEEP values: 0-5 69.8%, 6-10 27.5% and >10 2.6%. We observed a correlation (Pearson) between Grad(A-a)O₂ and PaFi of -0.84 (p<0.001). On performing multiple regression (dependent variable: Grad[A-a]O₂), the following variables were included in the model: PaFi, PEEP, APACHE IV and SOFA; coefficient of determination (R²) of 0.62 without PEEP and 0.72 with PEEP. We changed the PaFi formula, referring to it as PaFip (PaFi plus PEEP): Ln (PaFi/[PEEP+12]). Correlation index between PaFip and Grad(A-a)O₂: -0.9 (p<0.001). We performed linear regression (dependent variable: Grad[A-a]O₂) and used PaFip instead of PaFi. Only PaFi remained in the model, and was discretely complemented by APACHE IV; R²=0.8. By adding PEEP to the PaFi model (PaFip), we clearly improve the latter, as reflected by a better goodness of fit. Copyright © 2011 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  6. Effects of percutaneous transluminal septal myocardial ablation for obstructive hypertrophic cardiomyopathy on systolic and diastolic left ventricular function assessed by pressure-volume loops.

    PubMed

    Meliga, Emanuele; Steendijk, Paul; Valgimigli, Marco; Ten Cate, Folkert J; Serruys, Patrick W

    2008-04-15

    The aim of the present study was to determine the long-term effects of percutaneous transluminal septal myocardial ablation (PTSMA) on systolic and diastolic left ventricular (LV) functions in patients with obstructive hypertrophic cardiomyopathy (HC). Ten consecutive patients with symptomatic HC despite optimal medical treatment were referred for PTSMA at our center. LV systolic and diastolic functions were assessed by online LV pressure-volume loops obtained by conductance catheter at baseline and at 6 months after the procedure. At follow-up, the mean gradients at rest and after extrasystole were significantly decreased compared with baseline (88 +/- 29 to 21 +/- 11 mm Hg and 130 +/- 50 to 35 +/- 22 mm Hg, respectively, p <0.01 for the 2 comparisons). End-systolic and end-diastolic pressures significantly decreased (p <0.01), whereas end-systolic and end-diastolic LV volumes significantly increased (p <0.01 for the 2 comparisons). Cardiac output and stroke volume were unchanged, as were ejection fraction (p = 0.25) and maximum dP/dt (p = 0.13). The slope of the end-systolic pressure-volume relation was not decreased, indicating a preserved contractility. The relaxation constant time, end-diastolic stiffness, projected volume of the end-diastolic pressure-volume relation at 30 mm Hg, and diastolic stiffness constant showed a significant improvement of active and passive myocardial diastolic properties. In conclusion, PTSMA is an effective method in the treatment of symptomatic patients with HC. At 6-month follow-up, the LV-aortic gradient was decreased and active and passive LV diastolic properties were increased. Myocardial contractility was not decreased and general hemodynamics was maintained.

  7. Assessment of the relationship between stenosis severity and distribution of coronary artery stenoses on multislice computed tomographic angiography and myocardial ischemia detected by single photon emission computed tomography

    PubMed Central

    Tamarappoo, Balaji K.; Gutstein, Ariel; Cheng, Victor Y.; Nakazato, Ryo; Gransar, Heidi; Dey, Damini; Thomson, Louise E. J.; Hayes, Sean W.; Friedman, John D.; Germano, Guido; Slomka, Piotr J.

    2010-01-01

    Background The relationship between luminal stenosis measured by coronary CT angiography (CCTA) and severity of stress-induced ischemia seen on single photon emission computed tomographic myocardial perfusion imaging (SPECT-MPI) is not clearly defined. We sought to evaluate the relationship between stenosis severity assessed by CCTA and ischemia on SPECT-MPI. Methods and Results ECG-gated CCTA (64 slice dual source CT) and SPECT-MPI were performed within 6 months in 292 patients (ages 26-91, 73% male) with no prior history of coronary artery disease. Maximal coronary luminal narrowing, graded as 0, ≥25%, 50%, 70%, or 90% visual diameter reduction, was consensually assessed by two expert readers. Perfusion defect on SPECT-MPI was assessed by computer-assisted visual interpretation by an expert reader using the standard 17 segment, 5 point-scoring model (stress perfusion defect of ≥5% = abnormal). By SPECT-MPI, abnormal perfusion was seen in 46/292 patients. With increasing stenosis severity, positive predictive value (PPV) increased (42%, 51%, and 74%, P = .01) and negative predictive value was relatively unchanged (97%, 95%, and 91%) in detecting perfusion abnormalities on SPECT-MPI. In a receiver operator curve analysis, stenosis of 50% and 70% were equally effective in differentiating between the presence and absence of ischemia. In a multivariate analysis that included stenosis severity, multivessel disease, plaque composition, and presence of serial stenoses in a coronary artery, the strongest predictors of ischemia were stenosis of 50-89%, odds ratio (OR) 7.31, P = .001, stenosis ≥90%, OR 34.05, P = .0001, and serial stenosis ≥50% OR of 3.55, P = .006. Conclusions The PPV of CCTA for ischemia by SPECT-MPI rises as stenosis severity increases. Luminal stenosis ≥90% on CCTA strongly predicts ischemia, while <50% stenosis strongly predicts the absence of ischemia. Serial stenosis of ≥50% in a vessel may offer incremental value in addition

  8. Arterial insufficiency

    MedlinePlus

    ... is atherosclerosis or "hardening of the arteries." Fatty material (called plaque) builds up on the walls of your arteries. This causes them to become narrow and stiff. As a result, it is hard for blood to flow through your arteries. Blood flow may be suddenly ...

  9. The relationship between dipping-non-dipping arterial blood pressure pattern and frequency of restless leg syndrome with related factors.

    PubMed

    Ulu, Sena Memnune; Ahsen, Ahmet; Akcı, Önder; Yaman, Fatima; Demir, Kasım; Yaman, Gökhan; Yüksel, Şeref; Acartürk, Gürsel

    2015-04-01

    The lack of nocturnal decline in blood pressure (BP) is associated with an increase in cardiovascular events. Restless leg syndrome (RLS) is an uncomfortable feeling in which the patient wants to budge the legs with ache in the legs. RLS also increases the hypertension and cardiovascular risk. In this study, we aimed to evaluate the relationship between dipping and non-dipping blood pressure patterns with RLS and its severity. Two hundred patients who had 24-hour ambulatory blood pressure monitoring (ABPM) were enrolled into this cross-sectional study. They were classified by blood pressure pattern as dipping and non-dipping. Then, 100 patients with the dipper pattern and 100 patients with the non-dipper pattern were chosen. A questionnaire for RLS diagnosis that was prepared by the International RLS Study Group was given performed to the patients. RLS symptom score was higher in patients with non-dipping blood pressure patterns (NDBPP), and patients with NDBPP had more severe RLS. Beside this, there were no differences in terms of RLS frequency in dipping and non-dipping blood pressure patterns. As a conclusion, dipping and non-dipping blood pressure patterns do not increase RLS risk. But, if patients with NDBPP have RLS, they have more severe RLS. So, we suggest that evaluating a patient with a non-dipping blood pressure pattern, considering RLS, would be helpful to ameliorate the quality of life of the patient.

  10. The impact of accelerometer wear location on the relationship between step counts and arterial stiffness in adults treated for hypertension and diabetes.

    PubMed

    Cooke, Alexandra B; Daskalopoulou, Stella S; Dasgupta, Kaberi

    2017-08-24

    Accelerometer placement at the wrist is convenient and increasingly adopted despite less accurate physical activity (PA) measurement than with waist placement. Capitalizing on a study that started with wrist placement and shifted to waist placement, we compared associations between PA measures derived from different accelerometer locations with a responsive arterial health indicator, carotid-femoral pulse wave velocity (cfPWV). Cross-sectional study. We previously demonstrated an inverse association between waist-worn pedometer-assessed step counts (Yamax SW-200, 7 days) and cfPWV (-0.20m/s, 95% CI -0.28, -0.12 per 1000 step/day increment) in 366 adults. Participants concurrently wore accelerometers (ActiGraph GT3X+), most at the waist but the first 46 at the wrist. We matched this subgroup with participants from the 'waist accelerometer' group (sex, age, and pedometer-assessed steps/day) and assessed associations with cfPWV (applanation tonometry, Sphygmocor) separately in each subgroup through linear regression models. Compared to the waist group, wrist group participants had higher step counts (mean difference 3980 steps/day; 95% CI 2517, 5443), energy expenditure (967kcal/day, 95% CI 755, 1179), and moderate-to-vigorous-PA (138min; 95% CI 114, 162). Accelerometer-assessed step counts (waist) suggested an association with cfPWV (-0.28m/s, 95% CI -0.58, 0.01); but no relationship was apparent with wrist-assessed steps (0.02m/s, 95% CI -0.24, 0.27). Waist but not wrist ActiGraph PA measures signal associations between PA and cfPWV. We urge researchers to consider the importance of wear location choice on relationships with health indicators. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  11. [Analysis of relationships among syndrome, therapeutic treatment, and Chinese herbal medicine in patients with coronary artery disease based on complex networks].

    PubMed

    Gao, Zhu-ye; Zhang, Jing-chun; Xu, Hao; Shi, Da-zhuo; Fu, Chang-geng; Qu, Dan; Zhou, Xue-zhong

    2010-03-01

    To analyze the relationships among syndrome, therapeutic method and Chinese herbal medicine in patients with coronary artery disease (CAD). Using cross-sectional survey, we collected the clinical information of hospitalized CAD patients through individualized Information Acquisition Platform of CAD. The relationships among syndrome, therapeutic treatment and Chinese herbs were excavated by means of complex networks based on theory of correspondence between prescription and syndrome. The fundamental syndrome factors were blood stasis, qi deficiency, phlegm-turbid, yin deficiency, yang deficiency, qi stagnation, and blood deficiency. The therapeutic treatment mainly included activating blood circulation, clearing heat, invigorating qi, resolving turbid and phlegm, nourishing yin, warming yang qi, and dispersing obstruction. These methods constituted an association with major syndrome factors. The major syndrome factors constituted an association with the following Chinese herbal medicines: Huangqi (Radix Astragali Mongolici), Chenpi (Pericarpium Citri Reticulatae), Dihuang (Radix Rehmanniae), Chuanxiong (Rhizoma Chuanxiong), Baizhu (Rhizoma Atractylodis Macrocephalae), Taoren (Semen Persicae), Fuling (Poria), Gancao (Radix Glycyrrhizae), Banxia (Rhizoma Pinelliae), Zexie (Rhizoma Alismatis), Chishao (Radix Paeoniae Rubra), Danggui (Radix Angelicae Sinensis), Danshen (Radix Salviae Miltiorrhizae), Zhiqiao (Fructus Aurantii Submaturus.), Guizhi (Ramulus Cinnamomi) and Maidong (Radix Ophiopogonis Japonici). The efficacy of Chinese berbal medicines constituting association with syndrome factors mainly included alleviating pain, resolving turbid and phlegm, clearing heat, activating blood circulation, invigorating qi, cooling blood, promoting urination, resolving stagnation, removing toxic material, nourishing blood, regulating qi, quieting spirit, invigorating spleen, regulating menstruation, promoting defecation, moistening dryness, and resolving stasis. The therapeutic

  12. Impact of red blood cells count on the relationship between high density lipoproteins and the prevalence and extent of coronary artery disease: a single centre study [corrected].

    PubMed

    Schaffer, Alon; Verdoia, Monica; Cassetti, Ettore; Barbieri, Lucia; Perrone-Filardi, Pasquale; Marino, Paolo; De Luca, Giuseppe

    2015-07-01

    We have hypothesized that high red blood cells (RBC) count can potentially play an atheroprotective role in patients with coronary atherosclerosis. We, therefore, have investigated the relationship between high density lipoproteins cholesterol (HDL-C) and RBC levels in patients undergoing coronary angiography. Coronary artery disease (CAD) is a major cause of mortality. Impaired lipid profile represents a major risk factor for atherosclerosis. High density lipoprotein (HDL) is a key factor in atherosclerosis disease development. RBC can mimic HDL's reverse cholesterol transportation with a potential atheroprotective role. Coronary angiography has been evaluated in 3,534 patients. Fasting samples were collected for haematology and lipids levels assessment. Coronary disease was defined for at least 1 vessel stenosis >50 %. Patients were divided according to HDL-C and RBC tertiles. Lower HDL-C was significantly associated to the prevalence of CAD (84.8 vs 78.5 vs 67.3 %, p ≤ 0.001; adjusted OR [95 % CI] = 1.55 [1.3-1.8], p < 0.001) and severe CAD (30 % vs 30 % vs 24.4 %, p = 0.002; adjusted OR [95 % CI] = 1.08 [1.01-1.16], p = 0.02), this relationship was maintained even dividing our population according to RBC tertiles (p < 0.001).In conclusion, HDL-C levels are directly related to RBC count and inversely to the prevalence and extent of coronary disease. Higher RBC levels can reduce the risk of CAD in patients with lower HDL-C levels, suggesting an important atheroprotective role.

  13. Internal Carotid Artery and Its Relationship with Structures in Sellar Region: Anatomy Study and Its Clinical Applications.

    PubMed

    Zhang, Yishui; Yang, Wen

    2017-10-03

    Complications of the ICA in surgeries are rare but severe. This study aims to locate the ICA with 5 stationary bony structures in the sellar region: the anterior clinoid process (ACP), the tuberculum sellae, the bottom of the hypophyseal fossa, the posterior edge of the hypophyseal fossa and the post clinoid process and do measurements to determine their anatomic relationship with the ICA. After multiple planar reconstructions on computer tomographic angiography images of 120 ICA in 60 individuals, we defined the 5 bony structures as 5 origins in horizontal, sagittal and vertical planes with the 3D coordinate system and got the cross-sections of bilateral ICA on the coronal plane passing through each origin. We measured the distances between the cross-sections and the origins and angles between the horizontal plane and the line passing through the origin and the cross sections on each coronal plane. We also measured the distances between bilateral ICA on the 5 coronal planes. Besides, we measured the coordinate of the anterior edge of bilateral ICA taking the anterior clinoid process as the origin. With the three-dimensional coordinate system, we located the ICA to the bony structures in skull base. Distance between bilateral ICA on coronal planes is 18.8±2.9mm, 23.6±3.7mm, 19.9±3.4mm, 24.7±4.3mm, 23.5±3.5mm, from anterior to posterior respectively. The 3D coordinate system used in this study is of value in preoperational assessment and data we obtained indicate the safety ranges avoiding damage to the ICA in surgeries. Copyright © 2017. Published by Elsevier Inc.

  14. Mechanical Properties of Coronary Arteries and Internal Mammary Arteries Beyond Physiological Deformations

    DTIC Science & Technology

    2007-11-02

    initiate intimal hyperplasia , which could eventually lead to stenosis of the anastomosis. Therefore it is important to know more about the mechanical...the case for the muscular coronary artery. Fig. 3 shows the typical stress-strain relationship in circumferential direction of one coronary artery at...coronary artery is an artery of the muscular type, which means that the media consists mainly of smooth muscle cells. The IMA is an elastic artery

  15. Acute arterial occlusion - kidney

    MedlinePlus

    Acute renal arterial thrombosis; Renal artery embolism; Acute renal artery occlusion; Embolism - renal artery ... kidneys need a good blood supply. The main artery to the kidney is called the renal artery. ...

  16. A levels of endogenous gonadal hormones and their relationship with selected coronary artery disease risk factors among young women post myocardial infarction.

    PubMed

    Ablewska, Urszula; Jankowski, Krzysztof; Rzewuska, Ewa; Liszewska-Pfejfer, Danuta; Hryniewiecki, Tomasz

    2011-01-01

    In recent decades a significant raise in the incidence of myocardial infarction among young women has been recorded. It is presumed that, apart from the classical risk factors, other reasons exist for premature atherosclerosis in young women, related to the homeostasis of gonadal hormones. The aim of the study was to analyze the levels of gonadal hormones (estradiol, progesterone, follicle-stimulating hormone, luteinizing hormone, testosterone and dehydroepiandrosterone) measured in the luteal phase, in 65 normally menstruating women post myocardial infarction (MI) and to investigate a possible relationship between the hormone profile and selected coronary artery disease (CAD) risk factors. The levels of gonadal hormones: estradiol, progesterone, follicle-stimulating hormone, luteinizing hormone, testosterone and dehydroepiandrosterone were measured in the luteal phase. All examined women had normal mean levels of gonadal hormones. In the post MI patients leading a sedentary life style, a significantly lower mean progesterone concentration was observed (16.29 ± 9.11 versus 29.43 ± 21.14 nmol/l, p < 0.05) and significantly higher mean testosterone concentration (2.34 ± 0.98 versus 1.76 ± 1.09 nmol/l, p < 0.05) when compared to patients from the same group, but leading a more active life. In obese post MI women (BMI ≥ 30 kg/m(2)) a lower mean concentration of progesterone was detected (18.02 ± 8.12 versus 26.16 ± 14.72 nmol/l, p < 0.05), than in slimmer patients from the same group. In post MI women with a positive family history for CAD, a significantly higher mean concentration of testosterone was detected (2.31 ± 1.22 versus 1.67 ± 0.74 nmol/l, p < 0.05) than in patients with no family history. The results suggest a correlation between levels of gonadal hormones and classical CAD risk factors.

  17. Understanding bias in relationships between the food environment and diet quality: the Coronary Artery Risk Development in Young Adults (CARDIA) study.

    PubMed

    Rummo, Pasquale E; Guilkey, David K; Ng, Shu Wen; Meyer, Katie A; Popkin, Barry M; Reis, Jared P; Shikany, James M; Gordon-Larsen, Penny

    2017-10-05

    The relationship between food environment exposures and diet behaviours is unclear, possibly because the majority of studies ignore potential residual confounding. We used 20 years (1985-1986, 1992-1993 2005-2006) of data from the Coronary Artery Risk Development in Young Adults (CARDIA) study across four US cities (Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; Oakland, California) and instrumental variables (IV) regression to obtain causal estimates of longitudinal associations between the percentage of neighbourhood food outlets (per total food outlets within 1 km network distance of respondent residence) and an a priori diet quality score, with higher scores indicating higher diet quality. To assess the presence and magnitude of bias related to residual confounding, we compared results from causal models (IV regression) to non-causal models, including ordinary least squares regression, which does not account for residual confounding at all and fixed-effects regression, which only controls for time-invariant unmeasured characteristics. The mean diet quality score across follow-up was 63.4 (SD=12.7). A 10% increase in fast food restaurants (relative to full-service restaurants) was associated with a lower diet quality score over time using IV regression (β=-1.01, 95% CI -1.99 to -0.04); estimates were attenuated using non-causal models. The percentage of neighbourhood convenience and grocery stores (relative to supermarkets) was not associated with diet quality in any model, but estimates from non-causal models were similarly attenuated compared with causal models. Ignoring residual confounding may generate biased estimated effects of neighbourhood food outlets on diet outcomes and may have contributed to weak findings in the food environment literature. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Relationship of Change in Traditional Cardiometabolic Risk Factors to Change in Coronary Artery Calcification Among Individuals with Detectable Subclinical Atherosclerosis: The Multi-Ethnic Study of Atherosclerosis

    PubMed Central

    Arguelles, William; Llabre, Maria M.; Penedo, Frank J.; Daviglus, Martha L.; Sacco, Ralph L.; Liu, Kiang; Szklo, Moyses; Polak, Joseph F.; Eng, John; Burke, Gregory L.; Schneiderman, Neil

    2014-01-01

    Background/Objectives Data describing relationships between change in risk factors and coronary artery calcification (CAC) are lacking and could inform optimal cardiovascular disease prevention and treatment strategies. This study aimed to examine how change in traditional cardiometabolic risk factors related to change in CAC among individuals with detectable subclinical atherosclerosis. Methods Latent growth modeling was used to examine change in cardiometabolic risk factors (waist circumference, body mass index, systolic and diastolic blood pressure, high- and low-density lipoprotein cholesterol, triglycerides, and glucose) related to change in CAC up to an average 4.9-year follow-up in a multi-ethnic cohort of 3,398 asymptomatic individuals (57.8% men) who had detectable CAC (score > 0) at baseline, adjusting for baseline risk factor levels and CAC values, age, gender, race/ethnicity, smoking, family history of CVD, income, and use of antihypertensive, lipid-lowering, and glucose-lowering medications. Results Greater declines in blood pressure (systolic and diastolic) and low-density lipoprotein cholesterol at follow-up were each associated with greater CAC progression. The observed inverse associations were attributable to greater CAC progression in participants taking antihypertensive and lipid-lowering drugs who, as expected, had declines in blood pressure and lipid levels, respectively. These inverse associations did not emerge in participants not taking these medications. Conclusions Among individuals with subclinical atherosclerosis, the unexpected inverse associations observed between change in blood pressure and lipid levels with CAC progression emphasize the importance of considering medication use, and, when feasible, the severity and duration of disease, in exploring associations between risk factors and CAC change. PMID:24698232

  19. Influence of antihypertensive therapy on cerebral perfusion in patients with metabolic syndrome: relationship with cognitive function and 24-h arterial blood pressure monitoring.

    PubMed

    Efimova, Nataliya Y; Chernov, Vladimir I; Efimova, Irina Y; Lishmanov, Yuri B

    2015-08-01

    To investigate the regional cerebral blood flow, cognitive function, and parameters of 24-h arterial blood pressure monitoring in patients with metabolic syndrome before and after combination antihypertensive therapy. The study involved 54 patients with metabolic syndrome (MetS) investigated by brain single-photon emission computed tomography, 24-h blood pressure monitoring (ABPM), and comprehensive neuropsychological testing before and after 24 weeks of combination antihypertensive therapy. Patients with metabolic syndrome had significantly poorer regional cerebral blood flow compared with control group: by 7% (P = 0.003) in right anterior parietal cortex, by 6% (P = 0.028) in left anterior parietal cortex, by 8% (P = 0.007) in right superior frontal lobe, and by 10% (P = 0.00002) and 7% (P = 0.006) in right and left temporal brain regions, correspondingly. The results of neuropsychological testing showed 11% decrease in mentation (P = 0.002), and 19% (P = 0.011) and 20% (P = 0.009) decrease in immediate verbal and visual memory in patients with MetS as compared with control group. Relationships between the indices of ABPM, cerebral perfusion, and cognitive function were found. Data showed an improvement of regional cerebral blood flow, ABPM parameters, and indicators of cognitive functions after 6 months of antihypertensive therapy in patients with MetS. The study showed the presence of diffuse disturbances in cerebral perfusion is associated with cognitive disorders in patients with metabolic syndrome. Combination antihypertensive treatment exerts beneficial effects on the 24-h blood pressure profile, increases cerebral blood flow, and improves cognitive function in patients with MetS. © 2015 John Wiley & Sons Ltd.

  20. Relationship between the omega-3 index and specialized pro-resolving lipid mediators in patients with peripheral arterial disease taking fish oil supplements.

    PubMed

    Schaller, Melinda S; Zahner, Greg J; Gasper, Warren J; Harris, William S; Conte, Michael S; Hills, Nancy K; Grenon, S Marlene

    2017-06-24

    Oral supplementation with n-3 polyunsaturated fatty acids (PUFA) increases the omega-3 index, a biomarker of red blood cell eicosapentaenoic acid and docosahexaenoic acid, and plasma levels of biosynthesis pathway markers and potent lipid mediators involved in the resolution of inflammation among patients with peripheral arterial disease (PAD). We aimed to quantify the association between an upstream change in the omega-3 index and downstream changes in lipid mediator production. We conducted a secondary analysis of the OMEGA-PAD I Trial, a randomized, placebo controlled trial investigating high-dose n-3 PUFA oral supplementation in PAD patients. Eighty subjects were randomized to either 4.4 g of fish oil or placebo for 1 month. Regression analyses using generalized estimating equation techniques were used to investigate the relationship between changes in the omega-3 index and changes in lipid mediators, pre- and post-intervention. In the fish oil group, there was a significant increase in the omega-3 index (5 ± 1% to 9 ± 2%, P < .001) as well as in the plasma levels of several downstream lipid mediator pathway markers of resolution, which are involved with the regulation of leukocyte effector function and host defense. A doubling of the omega-3 index correlated with increases of 2.3-fold in 18-hydroxy-eicosapentaenoic acid (HEPE; P < .0001), 1.7-fold in 15-HEPE (P = .03), 1.9-fold in 5-HEPE (P = .04), and 3.6-fold in 4-hydroxy-docosahexaenoic acid (P < .001). Among subjects with symptomatic PAD who took oral fish oil supplements for 1 month, observed changes in the omega-3 index were strongly associated with increases in downstream mediators in the biochemical pathways of resolution. Copyright © 2017 National Lipid Association. All rights reserved.

  1. Left ventricular outflow tract mean systolic acceleration as a surrogate for the slope of the left ventricular end-systolic pressure-volume relationship

    NASA Technical Reports Server (NTRS)

    Bauer, Fabrice; Jones, Michael; Shiota, Takahiro; Firstenberg, Michael S.; Qin, Jian Xin; Tsujino, Hiroyuki; Kim, Yong Jin; Sitges, Marta; Cardon, Lisa A.; Zetts, Arthur D.; hide

    2002-01-01

    OBJECTIVE: The goal of this study was to analyze left ventricular outflow tract systolic acceleration (LVOT(Acc)) during alterations in left ventricular (LV) contractility and LV filling. BACKGROUND: Most indexes described to quantify LV systolic function, such as LV ejection fraction and cardiac output, are dependent on loading conditions. METHODS: In 18 sheep (4 normal, 6 with aortic regurgitation, and 8 with old myocardial infarction), blood flow velocities through the LVOT were recorded using conventional pulsed Doppler. The LVOT(Acc) was calculated as the aortic peak velocity divided by the time to peak flow; LVOT(Acc) was compared with LV maximal elastance (E(m)) acquired by conductance catheter under different loading conditions, including volume and pressure overload during an acute coronary occlusion (n = 10). In addition, a clinically validated lumped-parameter numerical model of the cardiovascular system was used to support our findings. RESULTS: Left ventricular E(m) and LVOT(Acc) decreased during ischemia (1.67 +/- 0.67 mm Hg.ml(-1) before vs. 0.93 +/- 0.41 mm Hg.ml(-1) during acute coronary occlusion [p < 0.05] and 7.9 +/- 3.1 m.s(-2) before vs. 4.4 +/- 1.0 m.s(-2) during coronary occlusion [p < 0.05], respectively). Left ventricular outflow tract systolic acceleration showed a strong linear correlation with LV E(m) (y = 3.84x + 1.87, r = 0.85, p < 0.001). Similar findings were obtained with the numerical modeling, which demonstrated a strong correlation between predicted and actual LV E(m) (predicted = 0.98 [actual] -0.01, r = 0.86). By analysis of variance, there was no statistically significant difference in LVOT(Acc) under different loading conditions. CONCLUSIONS: For a variety of hemodynamic conditions, LVOT(Acc) was linearly related to the LV contractility index LV E(m) and was independent of loading conditions. These findings were consistent with numerical modeling. Thus, this Doppler index may serve as a good noninvasive index of LV contractility.

  2. Left ventricular outflow tract mean systolic acceleration as a surrogate for the slope of the left ventricular end-systolic pressure-volume relationship.

    PubMed

    Bauer, Fabrice; Jones, Michael; Shiota, Takahiro; Firstenberg, Michael S; Qin, Jian Xin; Tsujino, Hiroyuki; Kim, Yong Jin; Sitges, Marta; Cardon, Lisa A; Zetts, Arthur D; Thomas, James D

    2002-10-02

    The goal of this study was to analyze left ventricular outflow tract systolic acceleration (LVOT(Acc)) during alterations in left ventricular (LV) contractility and LV filling. Most indexes described to quantify LV systolic function, such as LV ejection fraction and cardiac output, are dependent on loading conditions. In 18 sheep (4 normal, 6 with aortic regurgitation, and 8 with old myocardial infarction), blood flow velocities through the LVOT were recorded using conventional pulsed Doppler. The LVOT(Acc) was calculated as the aortic peak velocity divided by the time to peak flow; LVOT(Acc) was compared with LV maximal elastance (E(m)) acquired by conductance catheter under different loading conditions, including volume and pressure overload during an acute coronary occlusion (n = 10). In addition, a clinically validated lumped-parameter numerical model of the cardiovascular system was used to support our findings. Left ventricular E(m) and LVOT(Acc) decreased during ischemia (1.67 +/- 0.67 mm Hg.ml(-1) before vs. 0.93 +/- 0.41 mm Hg.ml(-1) during acute coronary occlusion [p < 0.05] and 7.9 +/- 3.1 m.s(-2) before vs. 4.4 +/- 1.0 m.s(-2) during coronary occlusion [p < 0.05], respectively). Left ventricular outflow tract systolic acceleration showed a strong linear correlation with LV E(m) (y = 3.84x + 1.87, r = 0.85, p < 0.001). Similar findings were obtained with the numerical modeling, which demonstrated a strong correlation between predicted and actual LV E(m) (predicted = 0.98 [actual] -0.01, r = 0.86). By analysis of variance, there was no statistically significant difference in LVOT(Acc) under different loading conditions. For a variety of hemodynamic conditions, LVOT(Acc) was linearly related to the LV contractility index LV E(m) and was independent of loading conditions. These findings were consistent with numerical modeling. Thus, this Doppler index may serve as a good noninvasive index of LV contractility.

  3. Left ventricular outflow tract mean systolic acceleration as a surrogate for the slope of the left ventricular end-systolic pressure-volume relationship

    NASA Technical Reports Server (NTRS)

    Bauer, Fabrice; Jones, Michael; Shiota, Takahiro; Firstenberg, Michael S.; Qin, Jian Xin; Tsujino, Hiroyuki; Kim, Yong Jin; Sitges, Marta; Cardon, Lisa A.; Zetts, Arthur D.; Thomas, James D.

    2002-01-01

    OBJECTIVE: The goal of this study was to analyze left ventricular outflow tract systolic acceleration (LVOT(Acc)) during alterations in left ventricular (LV) contractility and LV filling. BACKGROUND: Most indexes described to quantify LV systolic function, such as LV ejection fraction and cardiac output, are dependent on loading conditions. METHODS: In 18 sheep (4 normal, 6 with aortic regurgitation, and 8 with old myocardial infarction), blood flow velocities through the LVOT were recorded using conventional pulsed Doppler. The LVOT(Acc) was calculated as the aortic peak velocity divided by the time to peak flow; LVOT(Acc) was compared with LV maximal elastance (E(m)) acquired by conductance catheter under different loading conditions, including volume and pressure overload during an acute coronary occlusion (n = 10). In addition, a clinically validated lumped-parameter numerical model of the cardiovascular system was used to support our findings. RESULTS: Left ventricular E(m) and LVOT(Acc) decreased during ischemia (1.67 +/- 0.67 mm Hg.ml(-1) before vs. 0.93 +/- 0.41 mm Hg.ml(-1) during acute coronary occlusion [p < 0.05] and 7.9 +/- 3.1 m.s(-2) before vs. 4.4 +/- 1.0 m.s(-2) during coronary occlusion [p < 0.05], respectively). Left ventricular outflow tract systolic acceleration showed a strong linear correlation with LV E(m) (y = 3.84x + 1.87, r = 0.85, p < 0.001). Similar findings were obtained with the numerical modeling, which demonstrated a strong correlation between predicted and actual LV E(m) (predicted = 0.98 [actual] -0.01, r = 0.86). By analysis of variance, there was no statistically significant difference in LVOT(Acc) under different loading conditions. CONCLUSIONS: For a variety of hemodynamic conditions, LVOT(Acc) was linearly related to the LV contractility index LV E(m) and was independent of loading conditions. These findings were consistent with numerical modeling. Thus, this Doppler index may serve as a good noninvasive index of LV contractility.

  4. Relationship of lipid and lipoprotein ratios with coronary severity in patients with new on-set coronary artery disease complicated with type 2 diabetics

    PubMed Central

    Du, Ying; Chen, Juan; Chen, Man-Hua; Yang, Sheng-Hua; Li, Sha; Guo, Yuan-Lin; Zhu, Cheng-Gang; Xu, Rui-Xia; Dong, Qian; Li, Jian-Jun

    2016-01-01

    Background Diabetes mellitus (DM) is associated with coronary artery disease (CAD) progression. Although previous studies have demonstrated the association of lipid and lipoprotein ratios with CAD, no data are currently available concerning the relationship between lipid and lipoprotein ratios and the severity of new on-set CAD in diabetics. Therefore, the aim of the present study was to investigate the usefulness of lipid and lipoprotein ratios in predicting the severity of CAD in patients with type 2 DM (T2DM). Methods A total of 380 consecutive T2DM patients with new on-set CAD were enrolled in the present study. Then, they were classified into the three groups according to Gensini score (GS) tertiles. The relationship between lipid and lipoprotein ratios currently used and the GS was investigated. Results Positive correlations of natural log-transformed GS (lnGS) with apolipoprotein B to apoA-I ratio (apoB/apoA-I), non-high-density lipoprotein cholesterol to apoA-I ratio (non-HDL-C/apoA-I), and low-density lipoprotein cholesterol to apoA-I ratio (LDL-C/apoA-I) were found (r = 0.18, 0.13, 0.12, respectively, all P < 0.05). Multivariate logistic analysis indicated apoB/apoA-I as the strongest predictor for high GS (OR = 5.67, 95% CI: 1.45–23.92, P = 0.003). Area under receivers operating characteristic curve of apoB/apoA-I was 0.63 (95% CI: 0.60–0.66, P = 0.001) for predicting high GS. The optimal cutoff value of apoB/apoA-I to predict high GS was 0.72 with the sensitivity of 61.2% and the specificity of 62.1%. Conclusions Lipid and lipoprotein ratios might be useful for predicting the severity of new on-set CAD in T2DM patients, and the apoB/apoA-I appeared as the most significant predictor in this population. PMID:27781059

  5. Brachioradial arteries with anastomotic arteries connecting to brachial arteries bilaterally.

    PubMed

    Hong, Tong; Qiuhong, Dan; Haipeng, Cai

    2010-01-01

    We present a patient with a failed radial coronary angioplasty as a result of bilateral brachioradial arteries, the radial arteries anomalously originating from the axillary arteries. We review the literature concerning abnormal origins of the radial artery and propose the left ulnar artery as optimal access of choice in cases with a right brachioradial artery of relatively small size in its proximal part.

  6. Ventricular-arterial uncoupling in heart failure with preserved ejection fraction after myocardial infarction in dogs - invasive versus echocardiographic evaluation.

    PubMed

    Mathieu, Myrielle; El Oumeiri, Bachar; Touihri, Karim; Hadad, Ielham; Mahmoudabady, Maryam; Thoma, Philippe; Metens, Thierry; Bartunek, Jozef; Heyndrickx, Guy R; Brimioulle, Serge; Naeije, Robert; Mc Entee, Kathleen

    2010-06-29

    Heart failure with preserved left ventricular ejection fraction and abnormal diastolic function is commonly observed after recovery from an acute myocardial infarction. The aim of this study was to investigate the physiopathology of heart failure with preserved ejection fraction in a model of healed myocardial infarction in dogs. Echocardiography, levels of neurohormones and conductance catheter measurements of left ventricular pressure-volume relationships were obtained in 17 beagle dogs 2 months after a coronary artery ligation, and in 6 controls. Healed myocardial infarction was associated with preserved echocardiographic left ventricular ejection fraction (0.57 +/- 0.01, mean +/- SEM) and altered Doppler mitral indices of diastolic function. NT-proBNP was increased, aldosterone was decreased, and norepinephrine was unchanged. Invasive measurements showed a markedly decreased end-systolic elastance (2.1 +/- 0.2 vs 6.1 +/- 0.8, mmHg/ml, p < 0.001) and end-systolic elastance to effective arterial elastance ratio (0.6 +/- 0.1 vs 1.4 +/- 0.2, p < 0.001), with altered active relaxation (dP/dtmin -1992 +/- 71 vs -2821 +/- 305, mmHg/s, p < 0.01) but preserved left ventricular capacitance (70 +/- 6 vs 61 +/- 3, ml at 20 mmHg, p = NS) and stiffness constant. Among echocardiographic variables, the wall motion score index was the most reliable indicator of cardiac contractility while E', E/A and E'/A' were correlated to dP/dtmin. In the canine model of healed myocardial infarction induced by coronary ligation, heart failure is essentially characterized by an altered contractility with left ventricular-arterial uncoupling despite vascular compensation rather than by abnormal diastolic function.

  7. Ventricular-arterial uncoupling in heart failure with preserved ejection fraction after myocardial infarction in dogs - invasive versus echocardiographic evaluation

    PubMed Central

    2010-01-01

    Background Heart failure with preserved left ventricular ejection fraction and abnormal diastolic function is commonly observed after recovery from an acute myocardial infarction. The aim of this study was to investigate the physiopathology of heart failure with preserved ejection fraction in a model of healed myocardial infarction in dogs. Methods Echocardiography, levels of neurohormones and conductance catheter measurements of left ventricular pressure-volume relationships were obtained in 17 beagle dogs 2 months after a coronary artery ligation, and in 6 controls. Results Healed myocardial infarction was associated with preserved echocardiographic left ventricular ejection fraction (0.57 ± 0.01, mean ± SEM) and altered Doppler mitral indices of diastolic function. NT-proBNP was increased, aldosterone was decreased, and norepinephrine was unchanged. Invasive measurements showed a markedly decreased end-systolic elastance (2.1 ± 0.2 vs 6.1 ± 0.8, mmHg/ml, p < 0.001) and end-systolic elastance to effective arterial elastance ratio (0.6 ± 0.1 vs 1.4 ± 0.2, p < 0.001), with altered active relaxation (dP/dtmin -1992 ± 71 vs -2821 ± 305, mmHg/s, p < 0.01) but preserved left ventricular capacitance (70 ± 6 vs 61 ± 3, ml at 20 mmHg, p = NS) and stiffness constant. Among echocardiographic variables, the wall motion score index was the most reliable indicator of cardiac contractility while E', E/A and E'/A' were correlated to dP/dtmin. Conclusions In the canine model of healed myocardial infarction induced by coronary ligation, heart failure is essentially characterized by an altered contractility with left ventricular-arterial uncoupling despite vascular compensation rather than by abnormal diastolic function PMID:20587034

  8. Arterial calcifications

    PubMed Central

    Rennenberg, Roger J M W; Schurgers, Leon J; Kroon, Abraham A; Stehouwer, Coen D A

    2010-01-01

    Abstract Arterial calcifications as found with various imaging techniques, like plain X-ray, computed tomography or ultrasound are associated with increased cardiovascular risk. The prevalence of arterial calcification increases with age and is stimulated by several common cardiovascular risk factors. In this review, the clinical importance of arterial calcification and the currently known proteins involved are discussed. Arterial calcification is the result of a complex interplay between stimulating (bone morphogenetic protein type 2 [BMP-2], RANKL) and inhibitory (matrix Gla protein, BMP-7, osteoprotegerin, fetuin-A, osteopontin) proteins. Vascular calcification is especially prevalent and related to adverse outcome in patients with renal insufficiency and diabetes mellitus. We address the special circumstances and mechanisms in these patient groups. Treatment and prevention of arterial calcification is possible by the use of specific drugs. However, it remains to be proven that reduction of vascular calcification in itself leads to a reduced cardiovascular risk. PMID:20716128

  9. Location of the popliteal artery and its relationship with the vascular risk in the suture of the posterior horn of the lateral meniscus.

    PubMed

    Sanz-Pérez, M; García-Germán, D; Ruiz-Díaz, J; Navas-Pernía, I; Campo-Loarte, J

    2015-01-01

    The proximity of the posterior horn of the lateral meniscus to the popliteal artery determines a risk of vascular injury in its suture. The aim of this study is to determine the location of the popliteal artery, and to establish the minimal distance from the posterior wall of the lateral meniscus to the artery, the common peroneal nerve (CPN), and its correlation to other variables. A total of 102 magnetic resonance studies were retrospectively reviewed from patients undergoing surgery at our institution. The axial section where the lateral meniscus could be clearly defined was selected, and the measurements were performed. The artery lay laterally to the midline in 94% of the cases. The minimal mean distance from the posterior wall of the lateral meniscus to the popliteal artery was 1.01cm. (0.32-1.74, SD: 0.304). The minimal mean distance to the CPN was 1.74cm. (0.75-2.87, SD: 0.374). No association was found between the minimal mean distance from the posterior wall to the popliteal artery with the height, weight, BMI, the lateral meniscus diameter, or the tibial plateau diameter. An association was found between the distance from the posterior wall to the CPN with the weight and the BMI. The proximity of the posterior horn to the popliteal artery should be considered when performing sutures. This distance is within the recommended depth for all-inside meniscus repair devices. This distance is not related to height, weight, BMI, lateral meniscus nor tibial plateau diameters. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

  10. Mesenteric artery ischemia

    MedlinePlus

    ... bowel - mesenteric; Dead gut - mesenteric; Atherosclerosis - mesenteric artery; Hardening of the arteries - mesenteric artery ... the aorta, the main artery from the heart. Hardening of the arteries occurs when fat, cholesterol, and ...

  11. Peripheral Artery Disease

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z Peripheral Artery Disease (PAD) Peripheral artery disease (PAD) refers to ... is peripheral artery disease treated? What is peripheral artery disease (PAD)? Peripheral artery disease, or PAD, refers ...

  12. Relationship of the 1793G-A and 677C-T polymorphisms of the 5,10-methylenetetrahydrofolate reductase gene to coronary artery disease.

    PubMed

    Kebert, Cory B; Eichner, June E; Moore, William E; Schechter, Eliot; Yaoi, Takuro; Vogel, Steve; Allen, Richard A; Dunn, S Terence

    2006-01-01

    Numerous studies have investigated the relationship between polymorphisms, in particular 677C-T and 1298A-C, of the methylene-tetrahydrofolate reductase (MTHFR) gene and coronary artery disease (CAD) with conflicting results. This study investigates the potential association of two point mutations in MTHFR, 677C-T and 1793G-A, along with other risk factors, with CAD. This is the first hospital-based study to investigate 1793G-A in this context. Genotype analysis was performed on 729 Caucasians and 66 African Americans undergoing coronary angiography using a novel PCR-based assay involving formation of Holliday junctions. Allelic frequencies for 677C-T were 66.2% C and 33.8% T for Caucasians and 90.9% C and 9.1% T for African Americans. With respect to the 1793G-A polymorphism, allelic frequencies were 94.7% G and 5.3% A for Caucasians and 99.2% G and 0.8% A for African Americans. Disease associations were examined in the Caucasian patients due to their greater genotype variability and larger number in the patient cohort. Results suggest that neither 677CT heterozygotes (OR-1.36; 95% CI 0.95 to 1.96) nor mutant homozygotes (OR-0.73; 95% CI 0.44 to 1.20) have either an increased or decreased risk for CAD compared to the 677CC genotype. Likewise, the 1793GA genotype did not demonstrate a statistically significant association with CAD compared to 1793GG patients (OR-0.79; 95% CI 0.47 to 1.33). Mean homocysteine levels (mumol/L) increased from normal to mutant for 677C-T (677CC: 10.2; 677CT: 11.0; 677TT: 11.6) and normal to heterozygous in 1793G-A (1793GG: 10.7; 1793GA: 11.5). These MTHFR polymorphisms did not contribute to the prediction of clinically defined CAD in Caucasians.

  13. Relationship of the 1793G-A and 677C-T Polymorphisms of the 5,10-Methylenetetrahydrofolate Reductase Gene to Coronary Artery Disease

    PubMed Central

    Kebert, Cory B.; Eichner, June E.; Moore, William E.; Schechter, Eliot; Yaoi, Takuro; Vogel, Steve; Allen, Richard A.; Dunn, S. Terence

    2006-01-01

    Numerous studies have investigated the relationship between polymorphisms, in particular 677C-T and 1298A-C, of the methylene-tetrahydrofolate reductase (MTHFR) gene and coronary artery disease (CAD) with conflicting results. This study investigates the potential association of two point mutations in MTHFR, 677C-T and 1793G-A, along with other risk factors, with CAD. This is the first hospital-based study to investigate 1793G-A in this context. Genotype analysis was performed on 729 Caucasians and 66 African Americans undergoing coronary angiography using a novel PCR-based assay involving formation of Holliday junctions. Allelic frequencies for 677C-T were 66.2% C and 33.8% T for Caucasians and 90.9% C and 9.1% T for African Americans. With respect to the 1793G-A polymorphism, allelic frequencies were 94.7% G and 5.3% A for Caucasians and 99.2% G and 0.8% A for African Americans. Disease associations were examined in the Caucasian patients due to their greater genotype variability and larger number in the patient cohort. Results suggest that neither 677CT heterozygotes (OR-1.36; 95% CI 0.95 to 1.96) nor mutant homozygotes (OR-0.73; 95% CI 0.44 to 1.20) have either an increased or decreased risk for CAD compared to the 677CC genotype. Likewise, the 1793GA genotype did not demonstrate a statistically significant association with CAD compared to 1793GG patients (OR-0.79; 95% CI 0.47 to 1.33). Mean homocysteine levels (μmol/L) increased from normal to mutant for 677C-T (677CC: 10.2; 677CT: 11.0; 677TT: 11.6) and normal to heterozygous in 1793G-A (1793GG: 10.7; 1793GA: 11.5). These MTHFR polymorphisms did not contribute to the prediction of clinically defined CAD in Caucasians. PMID:17264399

  14. Angioplasty and stent placement - peripheral arteries

    MedlinePlus

    Percutaneous transluminal angioplasty - peripheral artery; PTA - peripheral artery; Angioplasty - peripheral arteries; Iliac artery -angioplasty; Femoral artery - angioplasty; Popliteal artery - angioplasty; Tibial artery - angioplasty; Peroneal artery - ...

  15. Blood Flow in Arteries

    NASA Astrophysics Data System (ADS)

    Ku, David N.

    Blood flow in arteries is dominated by unsteady flow phenomena. The cardiovascular system is an internal flow loop with multiple branches in which a complex liquid circulates. A nondimensional frequency parameter, the Womersley number, governs the relationship between the unsteady and viscous forces. Normal arterial flow is laminar with secondary flows generated at curves and branches. The arteries are living organs that can adapt to and change with the varying hemodynamic conditions. In certain circumstances, unusual hemodynamic conditions create an abnormal biological response. Velocity profile skewing can create pockets in which the direction of the wall shear stress oscillates. Atherosclerotic disease tends to be localized in these sites and results in a narrowing of the artery lumena stenosis. The stenosis can cause turbulence and reduce flow by means of viscous head losses and flow choking. Very high shear stresses near the throat of the stenosis can activate platelets and thereby induce thrombosis, which can totally block blood flow to the heart or brain. Detection and quantification of stenosis serve as the basis for surgical intervention. In the future, the study of arterial blood flow will lead to the prediction of individual hemodynamic flows in any patient, the development of diagnostic tools to quantify disease, and the design of devices that mimic or alter blood flow. This field is rich with challenging problems in fluid mechanics involving three-dimensional, pulsatile flows at the edge of turbulence.

  16. Relationship between serum levels of triglycerides and vascular inflammation, measured as COX-2, in arteries from diabetic patients: a translational study

    PubMed Central

    2013-01-01

    Background Inflammation is a common feature in the majority of cardiovascular disease, including Diabetes Mellitus (DM). Levels of pro-inflammatory markers have been found in increasing levels in serum from diabetic patients (DP). Moreover, levels of Cyclooxygenase-2 (COX-2) are increased in coronary arteries from DP. Methods Through a cross-sectional design, patients who underwent CABG were recruited. Vascular smooth muscle cells (VSMC) were cultured and COX-2 was measured by western blot. Biochemical and clinical data were collected from the medical record and by blood testing. COX-2 expression was analyzed in internal mammary artery cross-sections by confocal microscopy. Eventually, PGI2 and PGE2 were assessed from VSMC conditioned media by ELISA. Results Only a high glucose concentration, but a physiological concentration of triglycerides exposure of cultured human VSMC derived from non-diabetic patients increased COX-2 expression .Diabetic patients showed increasing serum levels of glucose, Hb1ac and triglycerides. The bivariate analysis of the variables showed that triglycerides was positively correlated with the expression of COX-2 in internal mammary arteries from patients (r2 = 0.214, P < 0.04). Conclusions We conclude that is not the glucose blood levels but the triglicerydes leves what increases the expression of COX-2 in arteries from DP. PMID:23642086

  17. Pressure-volume curves: revisiting the impact of negative turgor during cell collapse by literature review and simulations of cell micromechanics.

    PubMed

    Ding, Yiting; Zhang, Yanxiang; Zheng, Quan-Shui; Tyree, Melvin T

    2014-07-01

    The Scholander-Hammel pressure chamber has been used in thousands of papers to measure osmotic pressure, πc , turgor pressure, Pt , and bulk modulus of elasticity, ε, of leaf cells by pressure-volume (PV) curve analysis. PV analysis has been questioned in the past. In this paper we use micromechanical analysis of leaf cells to examine the impact on PV curve analysis of negative turgor in living cells (Pt ). Models predict negative Pt (-0.1 to -1.8 MPa) depending on leaf cell size and shape in agreement with experimental values reported by J. J. Oertli. Modeled PV curves have linear regions even when Pt is quite negative, contrary to the arguments of M.T. Tyree. Negative Pt is totally missed by PV curve analysis and results in large errors in derived πc and Pt but smaller errors in ε. A survey of leaf cell sizes vs habitat (arid, temperate, and rainforest), suggests that the majority of published PV curves result in errors of 0.1-1.8 MPa in derived πc and Pt , whereby the error increases with decreasing cell size. We propose that small cell size in leaves is an ecological adaptation that permits plants to endure negative values of water potential with relatively little water loss. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  18. MR Elastography as a method for the assessment of myocardial stiffness: Comparison with an established pressure-volume model in a left ventricular model of the heart

    PubMed Central

    Kolipaka, Arunark; McGee, Kiaran P.; Araoz, Philip A.; Glaser, Kevin J.; Manduca, Armando; Romano, Anthony J.; Ehman, Richard L.

    2010-01-01

    Magnetic resonance elastography (MRE) measurements of shear stiffness (μ) in a spherical phantom experiencing both static and cyclic pressure variations were compared to those derived from an established pressure-volume (P-V) based model. A spherical phantom was constructed using a silicone rubber composite of 10 cm inner diameter and 1.3 cm thickness. A gradient echo MRE sequence was used to determine μ within the phantom at static and cyclic pressures ranging from 55 to 90 mmHg. Average values of μ using MRE were obtained within a region of interest and were compared to the P-V derived estimates. Under both static and cyclic pressure conditions, the P-V and MRE-based estimates of μ ranged from 98.2 to 155.1 kPa and 96.2 to 150.8 kPa, respectively. Correlation coefficients (R2) of 0.98 and 0.97 between the P-V and MRE shear modulus measurements were obtained under static and cyclic pressure conditions, respectively. For both static and cyclic pressures, MRE-based measures of μ agree with those derived from a P-V model suggesting that MRE can be used as a new, non-invasive method of assessing μ in sphere-like fluid filled organs such as the heart. PMID:19353657

  19. Divergent determinants of 18F-NaF uptake and visible calcium deposition in large arteries: relationship with Framingham risk score.

    PubMed

    Morbelli, Silvia; Fiz, Francesco; Piccardo, Arnoldo; Picori, Lorena; Massollo, Michela; Pestarino, Emanuela; Marini, Cecilia; Cabria, Manlio; Democrito, Alessia; Cittadini, Giuseppe; Villavecchia, Giampiero; Bruzzi, Paolo; Alavi, Abass; Sambuceti, Gianmario

    2014-02-01

    To compare regional vascular distribution and biological determinants of visible calcium load, as assessed by computed tomography, as well as of molecular calcium deposition as assessed by (18)F-NaF positron emission tomography. Eighty oncologic patients undergoing (18)F-NaF PET/CT scan were included in the study. Cardiovascular-risk stratification was performed according to a simplified version of the Framingham model [including age, diabetes, smoking, systolic blood pressure and body mass index (BMI)]. Arterial (18)F-NaF uptake was measured by drawing regions of interest comprising the arteries on each slice of the transaxial PET/CT and normalized to blood (18)F-NaF activity to obtain the arterial target-to-background ratio (TBR). The degree of arterial calcification (AC) was measured using a software program providing Agatston-like scores. Differences in mean values and regression analysis were tested. Predictors of AC and TBR were evaluated by univariate and multivariate analysis. p value of 0.05 was considered statistically significant. No correlation was documented between regional calcium load and regional TBR in any of the studied arterial segments. Visible calcium deposition was found to be dependent upon age while it was not influenced by all the remaining determinants of cardiovascular risk. By contrast, (18)F-NaF uptake was significantly correlated with all descriptors of cardiovascular risk, with the exception of BMI. Vascular (18)F-NaF uptake displays a different regional distribution, as well as different biological predictors, when compared to macroscopic AC. The tight dependency of tracer retention upon ongoing biological determinants of vascular damage suggests that this tool might provide an unexplored window on plaque pathophysiology.

  20. Relationship between media-to-lumen ratio of subcutaneous small arteries and wall-to-lumen ratio of retinal arterioles evaluated noninvasively by scanning laser Doppler flowmetry.

    PubMed

    Rizzoni, Damiano; Porteri, Enzo; Duse, Sarah; De Ciuceis, Carolina; Rosei, Claudia Agabiti; La Boria, Elisa; Semeraro, Francesco; Costagliola, Ciro; Sebastiani, Adolfo; Danzi, Paola; Tiberio, Guido A M; Giulini, Stefano M; Docchio, Franco; Sansoni, Giovanna; Sarkar, Annamaria; Rosei, Enrico Agabiti

    2012-06-01

    Structural alterations of subcutaneous small resistance arteries, as indicated by an increased media-to-lumen ratio, are frequently present in hypertensive and/or diabetic patients, and may represent the earliest alteration observed. Furthermore, media-to-lumen ratio of small arteries evaluated by micromyography has a strong prognostic significance; however, its extensive evaluation is limited by the invasivity of the assessment, since a biopsy of subcutaneous fat is needed. Noninvasive measurement of wall-to-lumen of retinal arterioles using scanning laser Doppler flowmetry (SLDF) has recently been introduced. However, this new technique has not yet been compared to micromyographic measurement, generally considered the gold standard approach. We investigated 40 individuals and patients, 24 of them were hypertensive patients and 16 normotensive individuals. All patients underwent a biopsy of subcutaneous fat during an elective surgical intervention. Subcutaneous small resistance arteries were dissected and mounted on a wire myograph, and media-to-lumen ratio was measured. In addition, an evaluation of wall-to-lumen ratio of retinal arterioles by SLDF was performed (Heidelberg Retina Flowmeter, Heidelberg Engineering). A close correlation was observed between media-to-lumen ratio of subcutaneous small arteries and wall-to-lumen ratio of retinal arterioles (r = 0.76, P < 0.001; P < 0.001, r(2) = 0.57). A noninvasive and easily repeatable procedure (intraobserver and interobserver variation coefficient <13%) such as an evaluation of the arterioles in the fundus oculi by SLDF may provide similar information regarding microvascular morphology compared with an invasive, accurate and prognostically relevant micromyographic measurement of media-to-lumen ratio of subcutaneous small arteries.

  1. Emergence of late-onset placental dysfunction: relationship to the change in uterine artery blood flow resistance between the first and third trimesters.

    PubMed

    Llurba, Elisa; Turan, Ozhan; Kasdaglis, Tania; Harman, Chris R; Baschat, Ahmet A

    2013-06-01

    To test if emergence of third-trimester (T3) placental dysfunction is related to the impedance change in uterine artery blood flow resistance between the first trimester (T1) and T3. Mean T1 and T3 uterine artery (mUtA) pulsatility index (PI) was measured in 1098 singletons. Each patient's individual mUtA-PI change was calculated ([(T3 PI - T1 PI/interval in days)] × 100; ΔmUtA-PI). This parameter and T1 and T3 mUtA-PI z-scores were related to placenta-related disease (PRD) and to constitutionally small neonates (CS). Forty-seven (5%) women had PRD and 83 (8.7%) delivered a CS neonate. T1 and T3 mUtA-PI z-scores were higher with PRD (0.418 versus -0.097 and 1.06 versus -0.13, p < 0.001 for all). Change in mUtA-PI (ΔmUtA PI) was similar for patients with PRD. However, the prevalence of PRD doubled with rising ΔmUtA-PI (11.1% versus 5.2%, p = 0.041). T3 uterine artery Doppler performs significantly better in detecting patients at risk for late-onset PRD than T1 or the gestational age change in uterine artery Doppler resistance This suggests that a proportion of late emerging PRD is not amenable to early screening by uterine artery Doppler. Further research is essential to identify the optimal screening strategy for late-onset placental dysfunction. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. Carotid artery surgery

    MedlinePlus

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... through the catheter around the blocked area during surgery. Your carotid artery is opened. The surgeon removes ...

  3. Morphometric analysis of small arteries in the human retina using adaptive optics imaging: relationship with blood pressure and focal vascular changes.

    PubMed

    Koch, Edouard; Rosenbaum, David; Brolly, Aurélie; Sahel, José-Alain; Chaumet-Riffaud, Philippe; Girerd, Xavier; Rossant, Florence; Paques, Michel

    2014-04-01

    The wall-to-lumen ratio (WLR) of retinal arteries is a recognized surrogate of end-organ damage due to aging and/or arterial hypertension. However, parietal morphometry remains difficult to assess in vivo. Recently, it was shown that adaptive optics retinal imaging can resolve parietal structures of retinal arterioles in humans in vivo. Here, using adaptive optics retinal imaging, we investigated the variations of parietal thickness of small retinal arteries with blood pressure and focal vascular damage. Adaptive optics imaging of the superotemporal retinal artery was done in 49 treatment-naive individuals [mean age (±SD) 44.9 years (±14); mean systolic pressure 132  mmHg (±22)]. Semi-automated segmentation allowed extracting parietal thickness and lumen diameter. In a distinct cohort, adaptive optics images of arteriovenous nicking (AVN; n = 12) and focal arteriolar narrowing (FAN; n = 10) were also analyzed qualitatively and quantitatively. In the cohort of treatment-naive individuals, by multiple regression taking into account age, body mass index, mean, systolic, diastolic and pulse blood pressure, the WLR was found positively correlated to mean blood pressure and age which in combination accounted for 43% of the variability of WLR. In the cohort of patients with focal vascular damage, neither FANs or AVNs showed evidence of parietal growth; instead, at sites of FANs, decreased outer diameter suggestive of vasoconstriction was consistently found, while at sites of AVNs venous narrowing could be seen in the absence of arteriovenous contact. High resolution imaging of retinal vessels by adaptive optics allows quantitative microvascular phenotyping, which may contribute to a better understanding and management of hypertensive retinopathy.

  4. Morphometric analysis of small arteries in the human retina using adaptive optics imaging: relationship with blood pressure and focal vascular changes

    PubMed Central

    Koch, Edouard; Rosenbaum, David; Brolly, Aurélie; Sahel, José-Alain; Chaumet-Riffaud, Philippe; Girerd, Xavier; Rossant, Florence; Paques, Michel

    2014-01-01

    Objectives: The wall-to-lumen ratio (WLR) of retinal arteries is a recognized surrogate of end-organ damage due to aging and/or arterial hypertension. However, parietal morphometry remains difficult to assess in vivo. Recently, it was shown that adaptive optics retinal imaging can resolve parietal structures of retinal arterioles in humans in vivo. Here, using adaptive optics retinal imaging, we investigated the variations of parietal thickness of small retinal arteries with blood pressure and focal vascular damage. Methods: Adaptive optics imaging of the superotemporal retinal artery was done in 49 treatment-naive individuals [mean age (±SD) 44.9 years (±14); mean systolic pressure 132 mmHg (±22)]. Semi-automated segmentation allowed extracting parietal thickness and lumen diameter. In a distinct cohort, adaptive optics images of arteriovenous nicking (AVN; n = 12) and focal arteriolar narrowing (FAN; n = 10) were also analyzed qualitatively and quantitatively. Results: In the cohort of treatment-naive individuals, by multiple regression taking into account age, body mass index, mean, systolic, diastolic and pulse blood pressure, the WLR was found positively correlated to mean blood pressure and age which in combination accounted for 43% of the variability of WLR. In the cohort of patients with focal vascular damage, neither FANs or AVNs showed evidence of parietal growth; instead, at sites of FANs, decreased outer diameter suggestive of vasoconstriction was consistently found, while at sites of AVNs venous narrowing could be seen in the absence of arteriovenous contact. Conclusion: High resolution imaging of retinal vessels by adaptive optics allows quantitative microvascular phenotyping, which may contribute to a better understanding and management of hypertensive retinopathy. PMID:24406779

  5. Carotid Artery Screening

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z Carotid Artery Screening What is carotid artery screening? Who should ... information about carotid artery screening? What is carotid artery screening? Screening examinations are tests performed to find ...

  6. Coronary Artery Bypass Grafting

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Coronary Artery Bypass Grafting? Coronary artery bypass grafting (CABG) is ... bypass multiple coronary arteries during one surgery. Coronary Artery Bypass Grafting Figure A shows the location of ...

  7. Tracheal tube cuff inflation guided by pressure volume loop closure associated with lower postoperative cuff-related complications: Prospective, randomized clinical trial

    PubMed Central

    Almarakbi, Waleed A.; Kaki, Abdullah M.

    2014-01-01

    Background: The main function of an endotracheal tube (ETT) cuff is to prevent aspiration. High cuff pressure is usually associated with postoperative complications. We tried to compare cuff inflation guided by pressure volume loop closure (PV-L) with those by just to seal technique (JS) and assess the postoperative incidence of sore throat, cough and hoarseness. Materials and Methods: In a prospective, randomized clinical trial, 100 patients’ tracheas were intubated. In the first group (n = 50), ETT cuff inflation was guided by PV-L, while in the second group (n. = 50) the ETT cuff was inflated using the JS technique. Intracuff pressures and volumes were measured. The incidence of postoperative cuff-related complications was reported. Results: Demographic data and durations of intubation were comparable between the groups. The use of PV-L was associated with a lesser amount of intracuff air [4.05 (3.7-4.5) vs 5 (4.8-5.5), P < 0.001] and lower cuff pressure than those in the JS group [18.25 (18-19) vs 33 (32-35), P ≤ 0.001]. The incidence of postextubation cuff-related complications was significantly less frequent among the PV-L group patients as compared with the JS group patients (P ≤ 0.009), except for hoarseness of voice, which was less frequent among the PV-L group, but not statistically significant (P ≤ 0.065). Multiple regression models for prediction of intra-cuff pressure after intubation and before extubation revealed a statistically significant association with the technique used for cuff inflation (P < 0.0001). Conclusions: The study confirms that PV-L-guided ETT cuff inflation is an effective way to seal the airway and associates with a lower ETT cuff pressure and lower incidence of cuff-related complications. PMID:25191181

  8. Validation of Noninvasive Indices Of Global Systolic Function in Patients with Normal and Abnormal Loading Conditions: A Simultaneous Echocardiography Pressure-Volume Catheterization Study

    PubMed Central

    Yotti, Raquel; Bermejo, Javier; Benito, Yolanda; Sanz, Ricardo; Ripoll, Cristina; Martínez-Legazpi, Pablo; Péerez del Villar, Candela; Elízaga, Jaime; González-Mansilla, Ana; Barrio, Alicia; Bañares, Rafael; Fernández-Avilés, Francisco

    2014-01-01

    Background Noninvasive indices based on Doppler-echocardiography are increasingly used in clinical cardiovascular research to evaluate LV global systolic chamber function. Our objectives were 1) to clinically validate ultrasound-based methods of global systolic chamber function to account for differences between patients in conditions of abnormal load, and 2) to assess their sensitivity to load confounders. Methods and Results Twenty-seven patients (8 dilated cardiomyopathy, 10 normal ejection fraction [EF], and 9 end-stage liver disease) underwent simultaneous echocardiography and left heart catheterization with pressure-conductance instrumentation. The reference index, maximal elastance (Emax) was calculated from pressure-volume loop data obtained during acute inferior vena cava occlusion. A wide range of values was observed for LV systolic chamber function (Emax: 2.8 ± 1.0 mmHg/ml), preload, and afterload. Amongst the noninvasive indices tested, the peak ejection intraventricular pressure difference (peak-EIVPD) showed the best correlation with Emax (R=0.75). A significant but weaker correlation with Emax was observed for EF (R=0.41), mid-wall fractional shortening (R=0.51), global circumferential strain(R=−0.53), and strain-rate (R=−0.46). Longitudinal strain and strain-rate failed to correlate with Emax, as did noninvasive single-beat estimations of this index. Principal component and multiple regression analyses demonstrated that peak-EIVPD was less sensitive to load, whereas EF and longitudinal strain and strain-rate were heavily influenced by afterload. Conclusions Current ultrasound methods have limited accuracy to characterize global LV systolic chamber function in a given patient. The Doppler-derived peak-EIVPD should be preferred for this purpose because it best correlates with the reference index and is more robust in conditions of abnormal load. PMID:24173273

  9. Use of lung pressure-volume curves and helium-sulphur hexafluoride washout to detect emphysema in subjects with mild airflow obstruction

    PubMed Central

    Pereira, R Petrik; Hunter, D; Pride, N B

    1981-01-01

    Mild abnormalities of peripheral lung function can be detected by simple methods, but it remains difficult to determine when these changes are the result of emphysema rather than disease of the airways. We have compared the value of measurements of lung distensibility and a multibreath test of helium (He) and sulphur hexafluoride (SF6) washout in distinguishing between six men with mild impairment of airway function caused by asthma (group A) and six men with similar airway function but probable widespread emphysema (group E). In group E there were striking abnormalities in the static pressure-volume curve of the lungs (reduced lung recoil pressures, increased chord compliance, increased shape factor) and the relation between maximum expiratory flow and lung recoil pressure fell within the normal range. In group A there were only minor abnormalities in lung distensibility and maximum expiratory flow was reduced at a standard lung recoil pressure. In addition carbon monoxide transfer coefficient was reduced in group E but normal in group A. Normal values for He-SF6 washout were similar to those previously described. Differences in He-SF6 washout between group A and group E men were small and in part accounted for by differences in functional residual capacity. In subjects with lung disease, end-tidal He and SF6 concentrations during washout were erratic and it was sometimes impossible to define a crossover point. We conclude that in our hands this technique is less useful for detecting acinar disease than are measurements of lung distensibility or carbon monoxide transfer. Considerable changes in lung distensibility may occur at an early stage in the natural history of emphysema and are readily distinguishable from the small changes that occur in mild asthma. Images PMID:7292378

  10. An automated method for measuring static pressure-volume curves of the respiratory system and its application in healthy lungs and after lung damage by oleic acid infusion.

    PubMed

    Zhao, Y; Rees, S E; Kjaergaard, S; Smith, B W; Larsson, A; Andreassen, S

    2007-03-01

    Elastic pressure/volume (PV) curves of the respiratory system have attracted increasing interest, because they may be helpful to optimize ventilator settings in patients undergoing mechanical ventilation. Clinically applicable methods need to be fast, use routinely available equipment, draw the inspiratory and expiratory PV curve limbs, separate the resistive and viscoelastic properties of the respiratory system from the elastic properties, and provide reproducible measurements. This paper presents a computer-controlled method for rapid measurements of static PV curves using a long inflation-deflation with pauses, and its evaluation in six pigs before and after lung damage caused by oleic acid. The method is fast, i.e. 20.5 +/- 1.9 s (mean +/- SD) in healthy lungs and 17.7 +/- 4.1 s in diseased lungs, this including inspiratory and expiratory pauses of 1.1 s duration. In addition the only equipment used was a clinical ventilator and a PC. For healthy and damaged lungs expiratory PV curve limbs were very reproducible and were at higher volume than the inspiratory limbs, indicating hysteresis. For damaged lungs inspiratory PV limbs were reproducible. For healthy lungs the inspiratory limbs were reproducible but only after the first inflation-deflation. It is possible that during the first inflation alveoli are recruited which are not derecruited on deflation, shifting the inspiratory limb of the PV curve. The paused long inflation-deflation technique provides a quick, automated measurement of static PV curves on both inspiratory and expiratory limbs using routinely available equipment in the intensive care unit.

  11. Arterial embolism

    MedlinePlus

    ... for embolization (especially to the brain) is mitral stenosis . Endocarditis (infection of the inside of the heart) can also cause arterial emboli. A common source for an embolus is from areas of hardening (atherosclerosis) in the aorta and other large blood vessels. These clots can ...

  12. The relationship between interventionists' experience and clinical and radiological outcome in intra-arterial treatment for acute ischemic stroke. A MR CLEAN pretrial survey.

    PubMed

    Beumer, Debbie; van Boxtel, Tiemen H; Schipperen, Stefanie; van Zwam, Wim H; Lycklama À Nijeholt, Geert J; Brouwer, Patrick A; Jenniskens, Sjoerd F M; Schonewille, Wouter J; Vos, Jan Albert; van der Lugt, Aad; Roos, Yvo B; Majoie, Charles B; van Oostenbrugge, Robert J; Dippel, Diederik W J

    2017-06-15

    Intra-arterial treatment in acute ischemic stroke is safe and effective as recently shown in several randomized clinical trials. The level of experience of the interventionist performing the IAT procedure has not been studied. The present study investigates effects of interventionists' experience on technical aspects of the procedure and clinical outcome of the patient. In this study of 313 patients with a proximal intracranial arterial anterior circulation occlusion, treated in the Netherlands from 2002 until participation in the Multicenter Randomized Clinical trial of Endovascular treatment for acute ischemic stroke (MR CLEAN), data were collected retrospectively. The association of the senior interventionists' experience with duration of the procedure, adverse events, recanalization, neurological outcome, and functional outcome at discharge was analyzed. Multiple regression models adjusted for age, sex, stroke severity, carotid terminus occlusion, use of a retrievable stent and onset to door time were used. No association between interventionists' experience and recanalization, neurological outcome, or functional outcome was observed in a strict selection of patients. This strict selection include a start of intra-arterial treatment within 6h, no coagulation disturbances, systolic blood pressure<185mmHg and diastolic blood pressure<110mmHg), blood glucose level between 2.7 and 22.2mmol/L and the existence of a proximal intracranial occlusion. However, significant shorter procedure times were found with more experienced interventionists' [adjusted beta coefficient -0.67, 95% CI: -1.24 to -0.11], when using less strict inclusion criteria. No significant relation between the level of experience and either serious neurologic adverse events or poor outcomes was observed in this study of treatments by interventionists with experience of <50 previous procedures. We need further research to explore the relation of much higher levels of interventionists' and team

  13. Multimodal cardiovascular magnetic resonance quantifies regional variation in vascular structure and function in patients with coronary artery disease: Relationships with coronary disease severity

    PubMed Central

    2011-01-01

    Background Cardiovascular magnetic resonance (CMR) of the vessel wall is highly reproducible and can evaluate both changes in plaque burden and composition. It can also measure aortic compliance and endothelial function in a single integrated examination. Previous studies have focused on patients with pre-identified carotid atheroma. We define these vascular parameters in patients presenting with coronary artery disease and test their relations to its extent and severity. Methods and Results 100 patients with CAD [single-vessel (16%); two-vessel (39%); and three-vessel (42%) non-obstructed coronary arteries (3%)] were studied. CAD severity and extent was expressed as modified Gensini score (mean modified score 12.38 ± 5.3). A majority of carotid plaque was located in the carotid bulb (CB). Atherosclerosis in this most diseased segment correlated modestly with the severity and extent of CAD, as expressed by the modified Gensini score (R = 0.251, P < 0.05). Using the AHA plaque classification, atheroma class also associated with CAD severity (rho = 0.26, P < 0.05). The distal descending aorta contained the greatest plaque, which correlated with the degree of CAD (R = 0.222; P < 0.05), but with no correlation with the proximal descending aorta, which was relatively spared (R = 0.106; P = n. s.). Aortic distensibility varied along its length with the ascending aorta the least distensible segment. Brachial artery FMD was inversely correlated with modified Gensini score (R = -0.278; P < 0.05). In multivariate analysis, distal descending aorta atheroma burden, distensibility of the ascending aorta, carotid atheroma class and FMD were independent predictors of modified Gensini score. Conclusions Multimodal vascular CMR shows regional abnormalities of vascular structure and function that correlate modestly with the degree and extent of CAD. PMID:22017860

  14. Cerebral Arterial Fenestrations

    PubMed Central

    Cooke, Daniel L; Stout, Charles E; Kim, Warren T; Kansagra, Akash P; Yu, John Paul; Gu, Amy; Jewell, Nicholas P; Hetts, Steven W; Higashida, Randall T; Dowd, Christopher F; Halbach, Van V

    2014-01-01

    Summary Arterial fenestrations are an anatomic variant with indeterminate significance. Given the controversy surrounding fenestrations we sought their prevalence within our practice along with their association with other cerebrovascular anomalies. We retrospectively reviewed 10,927 patients undergoing digital subtraction angiography between 1992 and 2011. Dictated reports were searched for the terms “fenestration” or “fenestrated” with images reviewed for relevance, yielding 228 unique cases. A Medline database search from February 1964 to January 2013 generated 304 citations, 127 cases of which were selected for analysis. Cerebral arterial fenestrations were identified in 228 patients (2.1%). At least one aneurysm was noted in 60.5% of patients, with an aneurysm arising from the fenestration in 19.6% of patients. Aneurysmal subarachnoid hemorrhage or non-aneurysmal subarachnoid hemorrhage were present in 60.1% and 15.8%, respectively. For the subset of patients with an aneurysm arising directly from a fenestration relative to those patients with an aneurysm not immediately associated with a fenestration, the prevalence of aneurysmal subarachnoid hemorrhage was 66.7% vs. 58.6% (p = 0.58). Fenestrations were more often within the posterior circulation (73.2%) than the anterior circulation (24.6%), though there was no difference in the prevalence of aneurysms within these groups (61.1% vs. 60.7%, p = 1.0). Cerebral arterial fenestrations are an anatomic variant more often manifesting at the anterior communicating arterial complex and basilar artery and with no definite pathological relationship with aneurysms. PMID:24976087

  15. Effects of milrinone and epinephrine or dopamine on biventricular function and hemodynamics in an animal model with right ventricular failure after pulmonary artery banding.

    PubMed

    Hyldebrandt, Janus Adler; Sivén, Eleonora; Agger, Peter; Frederiksen, Christian Alcaraz; Heiberg, Johan; Wemmelund, Kristian Borup; Ravn, Hanne Berg

    2015-07-01

    Right ventricular (RV) failure due to chronic pressure overload is a main determinant of outcome in congenital heart disease. Medical management is challenging because not only contractility but also the interventricular relationship is important for increasing cardiac output. This study evaluated the effect of milrinone alone and in combination with epinephrine or dopamine on hemodynamics, ventricular performance, and the interventricular relationship. RV failure was induced in 21 Danish landrace pigs by pulmonary artery banding. After 10 wk, animals were reexamined using biventricular pressure-volume conductance catheters. The maximum pressure in the RV increased by 113% (P < 0.0001) and end-diastolic volume by 43% (P < 0.002), while left ventricular (LV) pressure simultaneously decreased (P = 0.006). Concomitantly, mean arterial pressure (MAP; -16%, P = 0.01), cardiac index (CI; -23%, P < 0.0001), and mixed venous oxygen saturation (SvO2 ; -40%, P < 0.0001) decreased. Milrinone increased CI (11%, P = 0.008) and heart rate (HR; 21%, P < 0.0001). Stroke volume index (SVI) decreased (7%, P = 0.03), although RV contractility was improved. The addition of either epinephrine or dopamine further increased CI and HR in a dose-dependent manner but without any significant differences between the two interventions. A more pronounced increase in biventricular contractility was observed in the dopamine-treated animals. LV volume was reduced in both the dopamine and epinephrine groups with increasing doses In the failing pressure overloaded RV, milrinone improved CI and increased contractility. Albeit additional dose-dependent effects of both epinephrine and dopamine on CI and contractility, neither of the interventions improved SVI due to reduced filling of the LV. Copyright © 2015 the American Physiological Society.

  16. Arterial switch.

    PubMed

    Planche, C; Lacour-Gayet, F; Serraf, A

    1998-01-01

    A relatively large spectra of anatomic variations are found within the unifying features of discordant ventriculoarterial connections. Variants that lend themselves to anatomic repair by the arterial switch operation are discussed, these include transposition of the great arteries with intact ventricular septum (TGA IVS), TGA associated with a ventricular septal defect (TGA VSD), double-outlet right ventricle with subpulmonary VSD (DORV VSD), and TGA or DORV with VSD associated with coarctation. Double discordance with VSD, which is currently treated by double switch or Rastelli and atrial switch and which probably represents, in our department, the only remaining indication for atrial switch, is not discussed. Also, we exclude TGA associated with pulmonary stenosis, which is treated by Rastelli or REV operation.

  17. Free volume of an epoxy resin and its relation to structural relaxation: Evidence from positron lifetime and pressure-volume-temperature experiments

    NASA Astrophysics Data System (ADS)

    Dlubek, Günter; Hassan, E. M.; Krause-Rehberg, Reinhard; Pionteck, Jürgen

    2006-03-01

    The microstructure of the free volume and its temperature dependence in the epoxy resin diglycidyl ether of bisphenol-A (DGEBA) have been examined using positron annihilation lifetime spectroscopy (PALS, 80-350K , 10-5Pa ) and pressure-volume-temperature (PVT, 293-470K , 0.1-200MPa ) experiments. Employing the Simha-Somcynsky lattice-hole theory (S-S eos), the excess (hole) free volume fraction h and the specific free and occupied volumes, Vf=hV and Vocc=(1-h)V , were estimated. From the PALS spectra analyzed with the new routine LT9.0 the hole size distribution, its mean, ⟨vh⟩ , and mean dispersion, σh , were calculated. ⟨vh⟩ varies from 35to130Å3 . From a comparison of ⟨vh⟩ with V and Vf , the specific hole number Nh' was estimated to be independent of the temperature [Nh(300K)=Nh'/V=0.65nm-3] . From comparison with reported dielectric and viscosity measurements, we found that the structural relaxation slows down faster than the shrinkage of the hole free volume Vf would predict on the basis of the free volume theory. Our results indicate that the structural relaxation in DGEBA operates via the free-volume mechanism only when liquidlike clusters of cells of the S-S lattice appear which contain a local free volume of ˜1.5 or more empty S-S cells. The same conclusion follows from the pressure dependency of the structural relaxation and Vf . It is shown that PALS mirrors thermal volume fluctuations on a subnanometer scale via the dispersion in the ortho-positronium lifetimes. Using a fluctuation approach, the temperature dependency of the characteristic length of dynamic heterogeneity, ξ , is estimated to vary from ξ=1.9nm at Tg to 1.0nm at T/Tg>1.2 . A model was proposed which relates the spatial structure of the free volume as concluded from PALS to the known mobility pattern of the dynamic glass transition at low (cooperative α -relaxation) and high ( a -relaxation) temperatures. We discuss possible reasons for the differences between the

  18. Segmental arterial mediolysis of varying phases affecting both the intra-abdominal and intracranial vertebral arteries: an autopsy case report.

    PubMed

    Ro, Ayako; Kageyama, Norimasa; Takatsu, Akihiro; Fukunaga, Tatsushige

    2010-01-01

    We report an autopsy case of segmental arterial mediolysis (SAM) of various phases occurring in both the intracranial vertebral artery (IVA) and intra-abdominal arteries. The patient was a 70-year-old male found dead in his house. The cause of death was massive intra-abdominal hemorrhage owing to a ruptured right gastroepiploic artery. Histopathological examination revealed that there was a broad arterial dissection as long as 20 cm in the right gastroepiploic artery associated with SAM in the injurious phase. In addition, SAM in the reparative phase was observed as organized arterial dissections in the left gastric artery. Furthermore, SAM in the reparative phase was detected as an arterial dissection in the right IVA undergoing an organizing process. These three lesions were considered to have developed at different times. SAM occurring in both the intra-abdominal and intracranial vertebral arteries is extremely rare. This coincidence may provide a clue to the relationship between SAM and spontaneous IVA dissection.

  19. Relationship between Arterial Inflow Rate and Venous Filling Index of the Lower Extremities Assessed by Air Plethysmography in Subjects with or without Axial Reflux in the Great Saphenous Vein.

    PubMed

    Shiraishi, Yasushi

    2014-01-01

    To evaluate the relationship between arterial inflow rate (AIR) and venous filling index (VFI) in limbs with or without varicose veins, assessed by air plethysmography (APG). A total of 142 patients (142 limbs) visiting our clinic with leg complaints, but without arterial and venous disease, were defined as the normal group (NG), and 65 patients (65 limbs) with leg varices were defined as the varicose vein group (VG). Both groups underwent duplex ultrasonography and APG to identify venous reflux and measure hemodynamic parameters, respectively. Examinations were performed at the first visit in the NG and before and one month after treatment in the VG. A strong correlation between resting AIR and VFI was found in the NG (r = 0.72) and postoperative VG (r = 0.71). Twenty-two and three limbs in the NG and postoperative VG, respectively, had a VFI over 2.0 mL/s because of the high AIR. In the VG, AIR tended to decrease after treatment (P >0.01). High leg AIR lead to high VFI measured by APG. AIR and VFI should be measured at the same session to assess venous hemodynamic changes after varicose vein treatment when residual venous reflux cannot be diagnosed with duplex ultrasonography.

  20. Greater impairments in cerebral artery compared with skeletal muscle feed artery endothelial function in a mouse model of increased large artery stiffness.

    PubMed

    Walker, Ashley E; Henson, Grant D; Reihl, Kelly D; Morgan, R Garrett; Dobson, Parker S; Nielson, Elizabeth I; Ling, Jing; Mecham, Robert P; Li, Dean Y; Lesniewski, Lisa A; Donato, Anthony J

    2015-04-15

    Increased large artery stiffness is a hallmark of arterial dysfunction with advancing age and is also present in other disease conditions such as diabetes. Increased large artery stiffness is correlated with resistance artery dysfunction in humans. Using a mouse model of altered arterial elastin content, this is the first study to examine the cause-and-effect relationship between large artery stiffness and peripheral resistance artery function. Our results indicate that mice with genetically greater large artery stiffness have impaired cerebral artery endothelial function, but generally preserved skeletal muscle feed artery endothelial function. The mechanisms for impaired cerebral artery endothelial function are reduced nitric oxide bioavailability and increased oxidative stress. These findings suggest that interventions that target large artery stiffness may be important to reduce disease risk associated with cerebral artery dysfunction in conditions such as advancing age. Advancing age as well as diseases such as diabetes are characterized by both increased large artery stiffness and impaired peripheral artery function. It has been hypothesized that greater large artery stiffness causes peripheral artery dysfunction; however, a cause-and-effect relationship has not previously been established. We used elastin heterozygote mice (Eln(+/-) ) as a model of increased large artery stiffness without co-morbidities unrelated to the large artery properties. Aortic stiffness, measured by pulse wave velocity, was ∼35% greater in Eln(+/-) mice than in wild-type (Eln(+/+) ) mice (P = 0.04). Endothelium-dependent dilatation (EDD), assessed by the maximal dilatation to acetylcholine, was ∼40% lower in Eln(+/-) than Eln(+/+) mice in the middle cerebral artery (MCA, P < 0.001), but was similar between groups in the gastrocnemius feed arteries (GFA, P = 0.79). In the MCA, EDD did not differ between groups after incubation with the nitric oxide (NO) synthase inhibitor N

  1. Flavonoids and arterial stiffness: promising perspectives.

    PubMed

    Lilamand, M; Kelaiditi, E; Guyonnet, S; Antonelli Incalzi, R; Raynaud-Simon, A; Vellas, B; Cesari, M

    2014-07-01

    Flavonoids are a group of polyphenol compounds, ubiquitously found in plants. Great emphasis has been given to their possible benefits for cardiovascular health. These beneficial effects may be mediated by a specific action on arterial walls. Arterial stiffness is a marker of vascular aging, increasingly used in the clinical setting and assessed by pulse wave velocity. It has shown to be a robust predictor of cardiovascular events and mortality. This review aims at providing a comprehensive evaluation of available intervention and observational studies examining the relationship between flavonoid consumption and arterial stiffness. A Medline(®) literature search was performed using the keywords "arterial stiffness" and "flavonoids". As a result, 2 cross-sectional and 16 intervention studies assessing the relationship between flavonoids intake and arterial stiffness were retained. Four intervention trials reported a significant decrease of arterial stiffness after a flavonoid-based intervention, independently from blood pressure changes. The two observational studies reported significant associations between a higher flavonoid consumption and a lower arterial stiffness. In this review, isoflavones, anthocyanins and to a lesser extent cocoa flavan-3-ols appeared to be the more efficient to improve vascular function. Despite their heterogeneity, preliminary data seem to support an improvement of the arterial stiffness related to flavonoid intake. However, further research on absorption and dose-response effects of the specific flavonoid subclasses on arterial structure is warranted. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. The relationship between inhibitors of the Wnt signalling pathway (Dickkopf-1(DKK1) and sclerostin), bone mineral density, vascular calcification and arterial stiffness in post-menopausal women.

    PubMed

    Hampson, Geeta; Edwards, Sylvie; Conroy, Soraya; Blake, Glen M; Fogelman, Ignac; Frost, Michelle L

    2013-09-01

    Epidemiological studies have shown an association between bone loss/osteoporosis and vascular calcification (VC). Recent studies have implicated the Wnt signalling pathway in the pathogenesis of VC. We investigated the association between circulating concentrations of Wnt inhibitors; DKK1 and sclerostin with bone mineral density (BMD), abdominal aortic calcification (AAC) and arterial stiffness in post-menopausal women. One hundred and forty six post-menopausal women aged (mean [SD]) 61.5[6.5] years were studied. Sclerostin and DKK1 were measured in serum. BMD was measured at the lumbar spine (LS), femoral neck (FN), total hip (TH). AAC was detected by Vertebral Fracture Assessment (VFA) imaging and quantified using an 8- and 24- point scoring methods. Arterial stiffness was determined by aortic pulse wave velocity (PWV). A significant positive correlation was observed between sclerostin and BMD at the FN (r = 0.166, p = 0.043) and TH (r = 0.165, p = 0.044). The association remained significant at the FN (p = 0.045) and TH (p = 0.026) following adjustment for confounders. No significant correlation was observed between DKK1 and BMD. In contrast, there was a significant negative correlation between log DKK1 and AAC (24-point score: r = -0.25, p = 0.008 and 8-point score: r = -0.21, p = 0.024). Subjects with AAC score of 1 or less had significantly higher DKK1 (p = 0.01). The association between DKK1 and AAC remained significant following correction for age, blood pressure, cholesterol (24-point score: p = 0.017, 8-point score: p = 0.044). In adjusted linear regression analysis, sclerostin was positively associated with AAC (24-point score: p = 0.048, 8-point score: p = 0.031). Subjects with a PWV>9 m/s had significantly higher sclerostin than those with PWV <9 m/s: 23.8[12.3], vs 29.7 [14] pmol/l, p = 0.03). No association was observed between DKK1 and PWV. The opposite association between AAC and the 2 Wnt signaling inhibitors is of interest and merits further

  3. Effect of setting high APRV guided by expiratory inflection point of pressure-volume curve on oxygen delivery in canine models of severe acute respiratory distress syndrome

    PubMed Central

    Li, Jia-Qiong; Xu, Hong-Yang; Li, Mao-Qin; Chen, Jing-Yu

    2016-01-01

    In the present study, the effect of setting high airway pressure release ventilation (APRV) pressure guided by an expiratory inflection point of pressure-volume (PV) curve following lung recruitment maneuver (RM) on oxygen delivery (DO2) in canine models of severe acute respiratory distress syndrome (ARDS) was examined. Canine models of severe ARDS were established by intravenous injection of oleic acid. After injection of sedative muscle relaxants, a PV curve plotted using the super-syringe technique, and the pressure at lower inflection point (LIP) at the inhale branch and the pressure at the point of maximum curvature (PMC) at the exhale branch were measured. The ventilation mode was biphasic positive airway pressure (BiPAP), an inspiration to expiration ratio of 1:2, and Phigh 40 cm H2O, Plow 25 cm H2O. Phigh was decreased to 30 cm H2O after 90 sec. The dogs were randomized into 3 groups after RM, i.e., Blip group, BiPAP Plow = LIP+2 cm H2O; Bpmc group, BiPAP Plow = PMC; and Apmc group. In the APRV group, Phigh was set as PMC, with an inspiratory duration of 4 sec and expiratory duration of 0.4 sec. PMC was 18±1.4 cm H2O, and LIP was 11±1.3 cm H2O. Thirty seconds after RM was stabilized, it was set as 0 h. Hemodynamics, oxygenation and DO2 were measured at 0, 1, 2 and 4 h after RM in ARDS dogs. The results demonstrated: i) cardiac index (CI) in the 3 groups, where CI was significantly decreased in the Bpmc group at 0, 1, 2 and 4 h after RM compared to prior to RM (P<0.05) as well as in the Blip and Apmc groups (P<0.05). CI in the Blip and Apmc groups was not significantly altered prior to and after RM. ii) Oxygenation at 0, 1, 2 and 4 h in the 3 groups was improved after RM and the oxygenation indices for the 3 groups at 1 and 2 h were not significantly different (P>0.05). However, the oxygenation index in the Blip group at 4 h was significantly lower than those at 0 h for the Apmc and Bpmc groups (P<0.05). Oxygenation for the Apmc group at 4 h was higher

  4. Carotid Artery Disease

    MedlinePlus

    ... brain with blood. If you have carotid artery disease, the arteries become narrow, usually because of atherosclerosis. ... one of the causes of stroke. Carotid artery disease often does not cause symptoms, but there are ...

  5. Peripheral arterial line (image)

    MedlinePlus

    A peripheral arterial line is a small, short plastic catheter placed through the skin into an artery of the arm or leg. The purpose of a peripheral arterial line is to allow continuous monitoring of blood pressure ...

  6. Investigation of Vitamin D-Binding Protein Polymorphism Impact on Coronary Artery Disease and Relationship with Longevity: Own Data and a Review

    PubMed Central

    Stakisaitis, Donatas; Lesauskaitė, Vita; Girdauskaitė, Milda; Janulionis, Ernestas; Ulys, Albertas; Benetis, Rimantas

    2016-01-01

    The aim of the study was to assess the effect of vitamin D-binding protein (DBP) polymorphism on coronary artery disease (CAD). DBP phenotypes were identified in the groups: control (n = 306), men suffering from CAD (n = 154), and long-lived individuals (n = 108). Isoelectric focusing of DBP phenotypes in serum was performed on polyacrylamide gel. Distribution of DBP phenotypes in the study groups was found to be in Hardy-Weinberg equilibrium. Gc1s-1s phenotype and Gc1s allele frequency in CAD groups were significantly higher than in control, and Gc1s allele frequency was found significantly more often in CAD compared with long-lived group (p < 0.05). The Gc2 allele frequency in control was higher as compared with Gc2 frequency in CAD group (p < 0.05). The Gc2-2 phenotype was more frequent in long-lived survivors than in the CAD group (p < 0.05). It was found that the Gc1s allele significantly increased the risk of CAD with the odds ratio (OR) equal to 1.45 (p < 0.02) and showed Gc2 to be related with a decreased risk of CAD (OR = 0.69; p < 0.03). Authors review the role of DBP in resistance to atherosclerosis and cancer as the main longevity determinants. PMID:27143969

  7. The Relationship Between Lymphocyte-to-Monocyte Ratio and Bare-Metal Stent In-Stent Restenosis in Patients With Stable Coronary Artery Disease.

    PubMed

    Murat, Sani Namik; Yarlioglues, Mikail; Celik, Ibrahim Etem; Kurtul, Alparslan; Duran, Mustafa; Kilic, Alparslan; Oksuz, Fatih

    2017-04-01

    In-stent restenosis (ISR) is a common clinical problem in patients with coronary artery disease treated with percutaneous coronary intervention. Inflammatory process plays a pivotal role in the development of ISR. Both lymphocytes and monocytes are associated with inflammatory status. Recently, it has been shown that the lymphocyte-to-monocyte ratio (LMR) is a novel inflammatory marker. We aimed to investigate the association of serum LMR levels and ISR in patients undergoing bare-metal stent (BMS) implantation. The study included 273 patients (aged 61 ± 11 years, 66.5% men) with a history of BMS implantation and a further control coronary angiography due to stable angina pectoris. Patients were divided into 2 groups: patients with and without ISR. The LMR levels were significantly lower in patients with ISR than in those without ISR (2.50 ± 0.95 vs 3.87 ± 1.51, respectively, P < .001). On multivariate logistic regression analysis, the LMR was independently associated with ISR (odds ratio [OR]: 0.310, 95% confidence interval: 0.166-0.579, P < .001) together with high-sensitivity C-reactive protein (OR: 1.244, P = .008), reason for stent implantation (OR: 6.566, P = .003), stent diameter (OR: 0.015, P < .001), and stent length (OR: 1.137, P = .007). In conclusion, LMR levels are inversely related to ISR in patients treated with BMS implantation.

  8. Omega-3 Status and the Relationship between Plasma Asymmetric Dimethylarginine and Risk of Myocardial Infarction in Patients with Suspected Coronary Artery Disease

    PubMed Central

    Borgeraas, Heidi; Strand, Elin; Ringdal Pedersen, Eva; Dierkes, Jutta; Ueland, Per Magne; Seifert, Reinhard; Wilberg, Eirik Rebnord; Bohov, Pavol; Berge, Rolf K.; Nilsen, Dennis W. T.; Nygård, Ottar

    2012-01-01

    Background. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase. A previous rat study revealed an ADMA lowering effect following treatment with omega-3 polyunsaturated fatty acids (n-3 PUFAs). We sought to examine if an association between plasma ADMA and risk of acute myocardial infarction (AMI) was modified by serum n-3 PUFA status. Methods. The cohort included 1364 patients who underwent coronary angiography for suspected coronary artery disease in 2000-2001. Fatal and nonfatal AMI events were registered until December 31, 2006. Risk associations with AMI were estimated across ADMA quartiles (linear trend) and the upper decile. Results. No association between concentration of any n-3 PUFA and ADMA was observed. Only ADMA levels in upper decile were significantly associated with AMI with a multivariate adjusted hazard ratio (HR) (95% confidence interval) versus the rest of the population of 2.11 (1.34, 3.32). The association was strengthened among patients with below median levels of α-linolenic acid (ALA) (HR 3.12 (1.64, 5.93)), but was only influenced by longer chain n-3 PUFA after additional adjustments for HbA1c, estimated glomerular filtration rate, and hypercholesterolemia. Conclusions. The association of ADMA with risk of AMI is influenced by serum n-3 PUFA and particularly ALA. PMID:23346455

  9. Genotype-phenotype relationship of F7 R353Q polymorphism and plasma factor VII coagulant activity in Asian Indian families predisposed to coronary artery disease.

    PubMed

    Shanker, Jayashree; Perumal, Ganapathy; Maitra, Arindam; Rao, Veena S; Natesha, B K; John, Shibu; Hebbagodi, Sridhar; Kakkar, Vijay V

    2009-12-01

    Elevated factor VII (FVII) level is a risk factor for coronary artery disease (CAD). We investigated the role of R353Q polymorphism in the F7 gene in 139 Indian families with CAD, comprising of 222 affected subjects, 105 unaffected subjects and 126 affected sibling pairs. Plasma per cent FVIIc activity (FVII.c activity) differed ignificantly across R353Q genotype (P < 0.0001). Frequency of subjects with RR and QQ genotypes were higher in 4th quartile and 1st quartile of FVII.c activity, respectively (P < 0.0001). F7 R353Q SNP was able to explain up to 7% of variation in FVII.c activity by regression analysis and an additive genetic component of variance of 28.04% by heritability analysis. Quantitative trait loci analysis showed suggestive linkage evidence of F7 SNP with per cent FVII.c activity (LOD score -1.82; P = 0.002). Individuals with RR and RQ genotypes carried an OR of 2.071 (95% c.i. = 1.506-2.850) and 2.472 (95% c.i. = 1.679-3.641), espectively, towards CAD risk. There was significant correlation of FVII.c activity with lipid markers, particularly among those with RR and RQ genotype after covariate adjustment. In conclusion, the F7 R353Q SNP appears to moderately influence plasma FVII.c activity and risk of CAD in Indians.

  10. Linearity of the Frank-Starling relationship in the intact heart: the concept of preload recruitable stroke work.

    PubMed

    Glower, D D; Spratt, J A; Snow, N D; Kabas, J S; Davis, J W; Olsen, C O; Tyson, G S; Sabiston, D C; Rankin, J S

    1985-05-01

    The Frank-Starling relationship generally has been examined with filling pressure as the index of preload, resulting in a curvilinear function that plateaus at higher filling pressures. To investigate this relationship further in the intact heart, 32 dogs were chronically instrumented with left ventricular and pleural micromanometers and with regional (10 dogs) or global (22 dogs) ultrasonic dimension transducers. Seven days after implantation, left ventricular pressure and regional or global dimensions were recorded in the conscious state. After autonomic blockade, preload was varied by vena caval occlusion. Myocardial function was assessed by calculating regional or global stroke work, and preload was measured as end-diastolic segment length or chamber volume. The relationship between stroke work and either end-diastolic segment length or chamber volume (termed the preload recruitable stroke work relationship) was highly linear in every study (mean r = .97) and could be quantified by a slope (MW) and x-intercept (LW). Previous nonlinear relationships between stroke work and filling pressure seemed to reflect the exponential diastolic pressure-volume curve. Over the physiologic range of systolic arterial pressures produced by infusion of nitroprusside or phenylephrine, no significant change was observed in MW or LW in the normal dog. Calcium infusion increased both regional and global MW by 71 +/- 19% and 65 +/- 9%, respectively (p less than .02), with no significant change in LW. To normalize for ventricular geometry and heart rate, stroke work was computed from circumferential stress-strain data and converted to myocardial power output, which was then plotted against end-diastolic circumferential strain. This relationship also was highly linear, and the slope, Mmp (mW/cm3 of myocardium), is proposed as a potential measure of intrinsic myocardial performance independent of loading, geometry, and heart rate.

  11. A Case-Control Study of the Relationship Between SLC22A3-LPAL2-LPA Gene Cluster Polymorphism and Coronary Artery Disease in the Han Chinese Population

    PubMed Central

    Song, Zi-Kai; Cao, Hong-Yan; Wu, Hai-Di; Zhou, Li-Ting; Qin, Ling

    2016-01-01

    Background Mutations in the solute carrier family 22 member 3 (SLC22A3), lipoprotein (a)-like 2 (LPAL2), and the lipoprotein (a) (LPA) gene cluster, which encodes apolipoprotein (a) [apo (a)] of the lipoprotein (a) [Lp (a)] lipoprotein particle, have been suggested to contribute to the risk of coronary artery disease (CAD), but the precise variants of this gene cluster have not yet been identified in Chinese populations. Objectives We sought to investigate the association between SLC22A3-LPAL2-LPA gene cluster polymorphisms and the risk of CAD in the Han Chinese population. Patients and Methods We recruited 551 CAD patients and 544 healthy controls for this case-control study. Four SNPs (rs9346816, rs2221750, rs3127596, and rs9364559) were genotyped in real time using the MassARRAY system (Sequenom; USA) in the SLC22A3-LPAL2-LPA gene cluster. All subjects were Chinese and of Han descent, and were recruited from the First Hospital of Jilin University based on convenience sampling from June 2009 to September 2012. Results The frequency of the minor allele G (34.8%) in rs9364559 was significantly higher in the CAD patients than in the healthy controls (29.4%) (P = 0.006). There was genotypic association between rs9364559 and CAD (P = 0.022), and these results still remained significant after adjustment for the conventional CAD risk factors through forward logistic regression analysis (P = 0.020, P = 0.019). Haplotype analyses from different blocks indicated that 11 haplotypes were associated with the risk of CAD. Seven haplotypes were associated with a reduced risk of CAD, whereas four haplotypes were associated with an increased risk of CAD. Conclusions Rs9364559 in the LPA gene may contribute to the risk of CAD in the Han Chinese population; haplotypes which contain rs9346816-G were all associated with an increased risk of CAD in this study. PMID:27621937

  12. Prevalence of anxiety and depression symptoms and their relationship with other coronary artery disease risk factors: A population-based study on 5900 residents in Southeast Iran.

    PubMed

    Najafipour, Hamid; Banivaheb, Ghodsiyeh; Sabahi, Abdolreza; Naderi, Nasrollah; Nasirian, Maryam; Mirzazadeh, Ali

    2016-04-01

    Anxiety and depression are reported as the most prevalent psychiatric disorders worldwide. Here, we studied the prevalence of such disorders with co-morbidities of coronary artery disease (CAD) risk factors in an urban population in Iran. 5900 people were selected from 15 to 75-years-olds through single-stage cluster sampling. In addition to examining them for CAD risk factors, Beck anxiety and depression inventories were used to measure anxiety and depression symptoms. The standardized population prevalence of such disorders is reported and the predictors of having anxiety or depression were assessed using Poisson regression model. Overall 25.4% had moderate and 22.7% had severe anxiety. Severe anxiety significantly and constantly increased by age groups (p=0.01). The risk for anxiety was higher among females (Adjusted Risk Ratio, ARR 1.2), and those who were student/soldier (ARR 1.07). Those with high level of physical activity were at lower risk for anxiety (ARR 0.92). The risk of depression (any level) was higher among females (ARR 1.3), those holding high-school level of education (ARR 1.41), and those who used opium either occasionally (ARR 1.17) or frequently (ARR 1.3). Both anxiety and depression were significantly associated with two main CAD risk factors, low physical activity and opium use. We found that the majority of residents in Kerman, particularly women, are suffering from mild to server depression and anxiety symptoms. Public health interventions to increase public awareness on such symptoms, screening and delivery of prevention and treatment services are required to prevent from the growing burden of such disorders and cardiovascular diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Modifiable risk factors control and its relationship with 1 year outcomes after coronary artery bypass surgery: insights from the REACH registry

    PubMed Central

    Mehta, Rajendra H.; Bhatt, Deepak L.; Steg, Ph. Gabriel; Goto, Shinya; Hirsch, Alan T.; Liau, Chiau-Suong; Röther, Joachim; Wilson, Peter W.F.; Richard, Alain-Jean; Eagle, Kim A.; Ohman, E. Magnus

    2008-01-01

    Aims To evaluate the influence of achieving secondary prevention target treatment goals for cardiovascular (CV) risk factors on clinical outcomes in patients with prior coronary artery bypass surgery (CABG). Methods and results Accordingly, we analysed treatment to target goals in patients with prior CABG and atherothrombotic disease or known risk factors (diabetes, hypertension, hypercholesterolaemia, smoking, obesity) enrolled in the global REduction in Atherothrombosis for Continued Health (REACH) Registry, and their association with 1 year outcomes. A total of 13 907 of 68 236 patients (20.4%) in REACH had a history of prior CABG, and 1 year outcomes data were available for 13 207 of these. At baseline <25, 25–<50, 50–<75, and ≥75% risk factors were at goal in 3.7, 12.9, 31.7, and 51.7% of patients, respectively. One-year composite rates of CV death, non-fatal MI, non-fatal stroke were inversely related to the proportion of risk factors at goal at baseline (age, gender, and region adjusted rates 6.1, 5.6, 5.2, and 4.3% of patients with <25, 25–<50, 50–<75, and >75% risk factors at goal, respectively; P for trend 0.059). Conclusion Risk-factor control varied greatly in CABG patients. Although CABG patients are frequently treated with appropriate therapies, these treatments fail to achieve an adequate level of prevention in many. This failure was associated with a trend for worse age-, gender-, and region-adjusted clinical outcomes. Thus, perhaps secondary prevention after CABG needs to focus on more comprehensive modification of risk factors to target goals in the hope of preventing subsequent CV events, and represents an opportunity to improve CV health. PMID:18996953

  14. Relationship between depression and health-related quality of life in patients undergoing coronary artery bypass grafting: a MOTIV-CABG substudy.

    PubMed

    Perrotti, Andréa; Mariet, Anne-Sophie; Durst, Camille; Monaco, Francesco; Vandel, Pierre; Monnet, Elisabeth; Chocron, Sidney

    2016-06-01

    Depression is associated with higher risk of death and major adverse cardiac events among patients undergoing coronary artery bypass grafting (CABG). This study aimed to investigate the impact of preoperative depression on health-related quality of life (HRQoL) changes over the first 12 postoperative months. Patients were the participants in the MOTIV-CABG study that was a single-center, non-stratified, randomized, double-blind, parallel-group, phase 4 trial, conducted between January 2006 and February 2012 at University Hospital, Besançon, France. The effect of preoperative depression (measured using the Beck Depression Inventory, BDI) on changes in SF-36 component summary scores [mental (MCS) and physical (PCS)] over time was tested using a generalized linear model for repeated measures. The presence of depression was defined as a BDI score >3. There were 359 patients in this study: 217 (60.4 %) had no preoperative depression, and 142 (39.6 %) had preoperative depression. During follow-up, the MCS and PCS scores increased in both groups. The improvement was of smaller magnitude in the group of patients depressed baseline as compared to those with no depression (difference in LSM = -7.45, p < 10(-3), for MCS, and -6.80, p < 10(-3), for PCS). Preoperative depression has a negative impact on HRQoL improvement during postoperative follow-up after CABG. It seems important to detect depression before CABG to begin antidepressant therapy and improve patients' HRQoL.

  15. Relationship of Insulin Resistance to Prevalence and Progression of Coronary Artery Calcification Beyond Metabolic Syndrome Components: Shiga Epidemiological Study of Subclinical Atherosclerosis.

    PubMed

    Yamazoe, Masahiro; Hisamatsu, Takashi; Miura, Katsuyuki; Kadowaki, Sayaka; Zaid, Maryam; Kadota, Aya; Torii, Sayuki; Miyazawa, Itsuko; Fujiyoshi, Akira; Arima, Hisatomi; Sekikawa, Akira; Maegawa, Hiroshi; Horie, Minoru; Ueshima, Hirotsugu

    2016-08-01

    The association between insulin resistance (IR) and coronary artery calcification (CAC) has been uncertain after adjustment for metabolic syndrome components. We aimed to evaluate whether IR is associated with CAC prevalence or progression independently of metabolic syndrome components. We conducted a population-based study in a random sample of Japanese men aged 40 to 79 years and determined IR using the homeostasis model assessment of insulin resistance (HOMA-IR). The associations of HOMA-IR and other diabetic parameters per 1-SD increase with CAC prevalence and progression were evaluated using multivariable logistic regression. Of 1006 total participants at baseline (mean age, 64±10 years), CAC prevalence was observed in 646 (64.2%), and of 789 participants at follow-up (mean duration, 4.9±1.3 years), CAC progression was observed in 365 (46.3%). After adjustment for covariates including metabolic syndrome components, higher HOMA-IR was independently associated with CAC prevalence (adjusted odds ratio 1.34, 95% confidence interval 1.10-1.63; P=0.003) and progression (odds ratio 1.32, 95% confidence interval 1.09-1.60; P=0.004). In participants without diabetes mellitus, positive associations were similarly observed (prevalence: odds ratio 1.29, 95% confidence interval 1.04-1.60; P=0.022; and progression: odds ratio 1.25, 95% confidence interval 1.01-1.55; P=0.042), whereas glucose and hemoglobin A1c were not associated with CAC prevalence and progression. Higher IR was associated with CAC prevalence and progression independently of metabolic syndrome components in Japanese men and also in those without diabetes mellitus. Among diabetic measures, IR and fasting insulin, but not glucose and hemoglobin A1c, predicted CAC progression in men without diabetes mellitus. © 2016 American Heart Association, Inc.

  16. A Longitudinal Relationship between Depressive Symptoms and Development of Metabolic Syndrome: the Coronary Artery Risk Development in Young Adults (CARDIA) Study

    PubMed Central

    Womack, Veronica Y.; De Chavez, Peter John; Albrecht, Sandra S.; Durant, Nefertiti; Loucks, Eric B.; Puterman, Eli; Redmond, Nicole; Siddique, Juned; Williams, David R.; Carnethon, Mercedes R.

    2016-01-01

    Objective Despite variability in the burden of elevated depressive symptoms by sex and race and differences in the incidence of metabolic syndrome, few prior studies describe the longitudinal association of depressive symptoms with metabolic syndrome in a diverse cohort. We tested whether baseline and time-varying depressive symptoms were associated with metabolic syndrome incidence in black and white men and women from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Methods Participants reported depressive symptoms using the Center for Epidemiologic Studies Depression (CES-D) Scale at 4 examinations between 1995 and 2010. At those same examinations, metabolic syndrome was determined. Cox proportional hazards models were used to examine associations of depressive symptoms on development of metabolic syndrome in 3,208 participants without metabolic syndrome at baseline. Results Over 15 years, the incidence rate of metabolic syndrome (per 10,000 person-years) varied by race and sex with the highest rate in black women (279.2), followed by white men (241.9), black men (204.4) and white women (125.3). Depressive symptoms (per SD higher) were associated with incident metabolic syndrome in white men (hazard ratio [HR]=1.25, 95% confidence interval [CI]: 1.08, 1.45) and white women (HR=1.17, 95% CI: 1.00, 1.37) following adjustment for demographic characteristics and health behaviors. There was no significant association between depression and metabolic syndrome among black men or black women. Conclusion Higher depressive symptoms contribute modestly to the onset of metabolic syndrome among white adults. PMID:27490849

  17. Evolution and degree of control of cardiovascular risk factors after 5 years of follow-up and their relationship with the incidence of peripheral arterial disease: ARTPER cohort.

    PubMed

    Forés, Rosa; Alzamora, María Teresa; Pera, Guillem; Valverde, Marta; Angla, Maria; Baena-Díez, José Miguel; Mundet-Tuduri, Xavier

    2017-02-09

    Although cardiovascular risk factors (CVRF) are well known, their degree of control is not optimal. The aim of this study is to assess the evolution and control of CVRFs after 5 years of monitoring a population-based cohort and their association with the incidence of peripheral arterial disease (PAD). Prospective cohort study recruited between 2006-2008. Second phase between 2011-2012. An ankle brachial index was determined for all participants in both phases. Demographic variables, CVRF and previous cardiovascular events, blood pressure, total cholesterol and its fractions (HDL, LDL), triglycerides, glucose and glycosylated hemoglobin levels in diabetic patients and the cardiovascular risk score according to the REGICOR table were recorded. A total of 2,125 individuals were analyzed. We observed an increase in the prevalence of hypertension (HT) (15.4%), diabetes (DM) (8.2%) and hypercholesterolemia (20.4%), with no changes in obesity and smoking. The cardiovascular risk determined on the basis of the REGICOR table remained at around 5.5%. We observed an increased control of CVRF throughout the follow-up period, except in the case of DM and obesity. In the multivariate analysis, uncontrolled HT 2-folded the risk of onset of PAD (odds ratio [OR] 2.3; 95% confidence interval [95% CI] 1.3-4.1), whereas smoking 5-folded this risk (OR 5.0; 95% CI 2.5-10.2). Smoking and uncontrolled HT increase the risk of onset of PAD in this population. Despite the increase in drug treatments, the control of CVRFs continues to be suboptimal. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  18. Left ventricular filling and early diastolic function at rest and during angina in patients with coronary artery disease.

    PubMed Central

    Dawson, J R; Gibson, D G

    1989-01-01

    Left ventricular diastolic function was studied in 11 patients with coronary artery disease. Single plane ventriculography (30 degrees right anterior oblique projection) was performed at rest and during an episode of angina immediately after a period of rapid atrial pacing. Left ventricular pressure was recorded simultaneously by a micromanometer tipped catheter. The ventriculograms were digitised frame by frame to derive continuous plots of left ventricular shape, volume, and rate of change of volume. The time constant (tau) of the fall in left ventricular pressure was determined from the exponential portion of pressure decay during isovolumic relaxation. Ventricular pressure-volume loops were constructed to study the left ventricular diastolic pressure-volume relation. The time of minimum left ventricular pressure was used to divide diastole into an early phase and a late phase. Angina was associated with an increase in end systolic volume and a fall in ejection fraction with no significant change in end diastolic volume. Peak left ventricular pressure was unchanged but left ventricular minimum and end diastolic pressures were both increased and the diastolic pressure-volume relation was moved upwards. The time constant of left ventricular pressure fall was prolonged. At rest more than 50% of the stroke volume entered the left ventricle during the period of early diastole. This proportion was significantly reduced during angina and as a consequence a significantly greater proportion of the stroke volume entered the ventricle during late diastole. Despite this, and although the left ventricular diastolic pressure-volume relation was moved upwards with angina, the mean slope of the relation during late diastole--that is, chamber stiffness--was not significantly altered. The upward shift of the left ventricular diastolic pressure-volume relation seen during angina is thus already apparent in early diastole, and its extent does not change during the later phase of

  19. Relationship of levels of Vitamin D with flow-mediated dilatation of brachial artery in patients of myocardial infarction and healthy control: A case–control study

    PubMed Central

    Malik, Sarthak; Giri, Subhash; Madhu, S. V.; Rathi, Vinita; Banerjee, B. D.; Gupta, Nikhil

    2016-01-01

    Background: Cardiovascular diseases (CVD) remain the leading cause of death worldwide. Vitamin D deficiency has been linked to increased risk of adverse CV events. Vitamin D deficiency may be responsible for endothelial dysfunction which in turn affects the onset and progression of coronary artery disease and its risk factors, directly or indirectly through various mechanisms. Materials and Methods: It was case–control study. A total of 50 cases of acute myocardial infarction (AMI) (aged 40–60 years), admitted to medicine emergency/CCU, were taken as per ACC/AHA 2007 guidelines. An equal number of age- and sex-matched controls were also taken. Risk factors of AMI, flow-mediated dilatation (FMD), and 25(OH)D levels were studied in all cases and controls. Correlation was also studied between FMD and 25(OH)D. Results: The mean values of FMD were 18.86 ± 5.39% and 10.35 ± 4.90% in controls and cases, respectively (P < 0.05). The endothelial dilatation after glyceryl trinitrate (GTN) was also studied and was found to be 26.175 ± 4.25% and 18.80 ± 5.72% in controls and cases, respectively (P < 0.05). The mean levels of 25(OH)D in controls and cases were 25.45 ± 12.17 and 14.53 ± 8.28 ng/ml, respectively. In this study, 56% of subjects were Vitamin D deficient, 25% were Vitamin D insufficient, and only 19% had Vitamin D in normal range. A positive correlation coefficient was found between FMD and 25(OH) Vitamin D levels (r = 0.841, P < 0.01). In this study, a positive correlation coefficient was also found between endothelial dilatation after GTN and 25(OH)D levels (r = 0.743, P < 0.01). Conclusion: In this study, it was found that FMD was markedly impaired in patients of AMI when compared to controls. It was also found that majority of the study population was Vitamin D deficient; however, the deficiency was more severe in patients of AMI. We also found out that FMD was positively correlated (r = 0.841) to the deficiency state of Vitamin D in all the study

  20. Temperament and Character Profiles and Psychiatric Comorbidities in Patients With Coronary Artery or Valvular Heart Disease: Relationship With Cardiac Disease Severity

    PubMed Central

    Bezgin, Cigdem Hazal; Bezgin, Tahir; Kesebir, Sermin

    2016-01-01

    Background We aimed to investigate whether the psychopathological symptoms and temperament-character dimensions observed in patients operated due to coronary artery disease (CAD) or valvular heart disease (VHD) differ among the patients and from healthy individuals. Methods Study population was composed of subjects with CAD, VHD and healthy controls (n = 50 in each group). Socio-demographic questionnaire, temperament and character inventory (TCI) and symptom check list-90-R (SCL-90-R) were applied to all groups. Groups were compared about temperament-character dimensions and scores of subscales of SCL-90-R. Results Harm avoidance was found to be higher in VHD group than those with CAD and, lower in healthy controls than both patient groups (P = 0.004). Reward dependence was similar among both patient groups and, was higher than healthy group (P = 0.015). Depression, anxiety, somatization, obsession and interpersonal sensitivity were found to be similar in both patient groups but they were higher than those in controls (P < 0.001, P < 0.001, P < 0.001, P = 0.002 and P = 0.003, respectively). Phobia was seen equally in CAD group and healthy controls and, was found to be lower in these than in VHD (P = 0.009). Anger score was in descending order in patients with VHD, CAD and healthy controls group (P = 0.010 and 0.001). Paranoia was in descending order in patients with VHD, CAD and controls (P = 0.015 and 0.001). A weak and inverse correlation was found between ejection fraction (EF) and the persistence dimension of temperament scaled by TCI in patients with VHD (r = -0.276, P = 0.052). An inverse correlation was observed between EF and the reward dependence dimension in CAD group (r = -0.195, P = 0.044). In patients with VHD, EF demonstrated an inversely weak (r = -0.289, P = 0.042), moderate (r = -0.360, P = 0.010) and strong (r = -0.649, P < 0.001) correlation with inter-personal sensitivity, phobia and paranoia, respectively. There was an inverse and weak

  1. Real-time Doppler-based arterial vascular impedance and peripheral pressure-flow loops: a pilot study.

    PubMed

    Thiele, Robert H; Bartels, Karsten; Esper, Stephen; Ikeda, Keita; Gan, Tong-Joo

    2014-02-01

    Arterial pressure-flow loops and vascular impedance provide additional data that could be used to assess the hemodynamic effects of therapeutic interventions in anesthetized patients. To evaluate the utility of such an approach, the authors sought to design a device that combines flow waveforms from an esophageal Doppler probe and pressure waveforms from a peripheral artery to produce real-time pressure-flow loops and estimates of arterial vascular impedance. Prospective, cohort study. Single center, university-based teaching hospital. Patients undergoing surgery in whom the attending anesthesiologist had opted to place an esophageal Doppler probe and a peripheral arterial catheter for hemodynamic monitoring. This was a non-interventional study designed to record pressure-flow loops and arterial vascular impedance intraoperatively using a novel, noninvasive device. Pressure-flow loops and arterial vascular impedance were measured noninvasively using radial artery pressure and descending thoracic aorta flow waveforms in real time. Real-time arterial vascular impedance and peripheral pressure-volume loops can be determined using available monitoring devices. Technical feasibility of this technology in patients is a crucial first step to permit meaningful evaluation of the clinical value of this approach for accurate determination of complex hemodynamic indices and, eventually, improvement of outcomes. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Carotid artery anatomy (image)

    MedlinePlus

    There are four carotid arteries, two on each side of the neck: right and left internal carotid arteries, and right and left external carotid arteries. The carotid arteries deliver oxygen-rich blood from the heart to the head and brain.

  3. Vapor resistant arteries

    NASA Technical Reports Server (NTRS)

    Shaubach, Robert M. (Inventor); Dussinger, Peter M. (Inventor); Buchko, Matthew T. (Inventor)

    1989-01-01

    A vapor block resistant liquid artery structure for heat pipes. A solid tube artery with openings is encased in the sintered material of a heat pipe wick. The openings are limited to that side of the artery which is most remote from the heat source. The liquid in the artery can thus exit the artery through the openings and wet the sintered sheath, but vapor generated at the heat source is unlikely to move around the solid wall of the artery and reverse its direction in order to penetrate the artery through the openings. An alternate embodiment uses finer pore size wick material to resist vapor entry.

  4. Arterial blood gases, pulmonary function and pathology in rats exposed to 0. 75 or 1. 0 ppM ozone

    SciTech Connect

    Pepelko, W.E.; Mattox, J.K.; Yang, Y.Y.

    1980-06-01

    Arterial blood gases, residual lung volume (RV), deflation pressure volume (PV) curves, pulmonary pathology and body weight changes were studied in rats exposed up to 14 days to either 0.75 or 1.0 ppM ozone. Arterial PO2 and body weights decreased progressively with length of exposure while PaCO2 and RV increased. The slope of the PV curve decreased in all groups exposed to ozone. Pathological changes in the lung increased in severity with concentration and length of exposure. The present findings have shown that arterial blood gas measurements represent a sensitive index of altered lung function in rats, a species very sensitive to ozone exposure.

  5. Systematic analysis on the relationship between luminal enhancement, convolution kernel, plaque density, and luminal diameter of coronary artery stenosis: a CT phantom study.

    PubMed

    Morsbach, Fabian; Berger, Nicole; Desbiolles, Lotus; Poropat, Tadea; Leschka, Sebastian; Alkadhi, Hatem; Stolzmann, Paul

    2013-06-01

    To systematically investigate into the relationships between luminal enhancement, convolution kernel, plaque density, and stenosis severity in coronary computed tomography (CT) angiography. A coronary phantom including 63 stenoses (stenosis severity, 10-90%; plaque densities, -100 to 1,000 HU) was loaded with increasing solutions of contrast material (luminal enhancement, 0-700 HU) and scanned in an anthropomorphic chest. CT data was acquired with prospective triggering using 64-section dual-source CT; reconstructions were performed with soft-tissue (B26f) and sharp convolution kernels (B46f). Two blinded and independent readers quantitatively assessed luminal diameter and CT number of plaque using electronic calipers. Measurement bias between phantom dimensions and CT measurements were calculated. Multivariate linear regression models identified predictors of bias. Inter- and intra-reader agreements of luminal diameter and CT number measurements were excellent (ICCs > 0.91, p < 0.01, each). Measurement bias of luminal diameter and plaque density was significantly (p < 0.01, each) lower (-12% and 58 HU, respectively) with B46f as opposed to B26f, especially in plaque densities >200 HU. Measurement bias was significantly (p < 0.01, each) correlated (ρ = 0.37-55 and ρ = -0.70-85) with the differences between luminal enhancement and plaque density. In multivariate models, bias of luminal diameter assessment with CT was correlated with plaque density (β = 0.09, p < 0.05). Convolution kernel (β = -0.29 and -0.38), stenosis severity (β = -0.45 and -0.38), and luminal enhancement (β = -0.11 and -0.29) represented independent (p < 0.05,each) predictors of measurement bias of luminal diameter and plaque number, respectively. Significant independent relationships exist between luminal enhancement, convolution kernel, plaque density, and luminal diameter, which have to be taken into account when performing, evaluating, and interpreting coronary CT angiography.

  6. Relationships between high oxygen extraction fraction in the acute stage and final infarction in reversible middle cerebral artery occlusion: an investigation in anesthetized baboons with positron emission tomography.

    PubMed

    Young, A R; Sette, G; Touzani, O; Rioux, P; Derlon, J M; MacKenzie, E T; Baron, J C

    1996-11-01

    Studies in humans suggest that regions that show maximal increases in brain oxygen extraction fraction (OEF) in the hours following an ischemic episode are those most vulnerable for infarction and are often, although not always, associated with the final site of infarction. To clarify this issue, we followed the hemodynamic and metabolic characteristics of regions with an initially maximally increased OEF and compared them with the ultimately infarcted region in an experimental stroke model. Positron emission tomography (PET) was used to obtain functional images of the brain prior to and following reversible unilateral middle cerebral artery occlusion (MCAO) in 11 anesthetized baboons. To model early reperfusion, the clips were removed 6 h after occlusion. Successive measurements of regional CBF (rCBF), regional CMRO2 (rCMRO2), regional cerebral blood volume, and regional OEF (rOEF) were performed during the acute (up to 2 days) and chronic (> 15 days) stage. Late magnetic resonance imaging (MRI) scans (co-registered with PET) were obtained to identify infarction. Reversible MCAO produced an MRI-measurable infarction in 6 of 11 baboons; the others had no evidence of ischemic damage. Histological analysis confirmed the results of the MRI investigation but failed to show any evidence of cortical ischemic damage. The lesion was restricted to the head of the caudate nucleus, internal capsule, and putamen. The infarct volume obtained was 0.58 +/- 0.31 cm3. The infarcts were situated in the deep MCA territory, while the area of initially maximally increased OEF was within the cortical mantle. The mean absolute rCBF value in the infarct region of interest (ROI) was not significantly lower than in the highest-OEF ROI until 1-2 days post-MCAO. Cerebral metabolism in the deep MCA territory was always significantly lower than that of the cortical mantle; decreases in CMRO2 in the former region were evident as early as 1 h post-MCAO. In the cortical mantle, the rOEF was

  7. Coronary Artery Fistula

    DTIC Science & Technology

    2007-04-01

    ascending aorta and pulmonary artery) and congenital coronary artery stenosis . Most coronary artery fistulas are congenital but may also...MILITARY MEDICINE, 172, 4: xi-xii, 2007 Military Medicine, Vol. 172, 4, April 2007 Radiology Corner Case #11 Coronary Artery Fistula...man with a single episode of vague sub- sternal chest pain was referred for evaluation of possible coronary artery disease. His medical history was

  8. Experimental evidence for negative turgor pressure in small leaf cells of Robinia pseudoacacia L versus large cells of Metasequoia glyptostroboides Hu et W.C.Cheng. 1. Evidence from pressure-volume curve analysis of dead tissue.

    PubMed

    Yang, Dongmei; Pan, Shaoan; Ding, Yiting; Tyree, Melvin T

    2017-03-01

    This paper provides a mini-review of evidence for negative turgor pressure in leaf cells starting with experimental evidence in the late 1950s and ending with biomechanical models published in 2014. In the present study, biomechanical models were used to predict how negative turgor pressure might be manifested in dead tissue, and experiments were conducted to test the predictions. The main findings were as follows: (i) Tissues killed by heating to 60 or 80 °C or by freezing in liquid nitrogen all became equally leaky to cell sap solutes and all seemed to pass freely through the cell walls. (ii) Once cell sap solutes could freely pass the cell walls, the shape of pressure-volume curves was dramatically altered between living and dead cells. (iii) Pressure-volume curves of dead tissue seem to measure negative turgor defined as negative when inside minus outside pressure is negative. (iv) Robinia pseudoacacia leaves with small palisade cells had more negative turgor than Metasequoia glyptostroboides with large cells. (v) The absolute difference in negative turgor between R. pseudoacacia and M. glyptostroboides approached as much as 1.0 MPa in some cases. The differences in the manifestation of negative turgor in living versus dead tissue are discussed. © 2016 John Wiley & Sons Ltd.

  9. Comparison of the effects of levosimendan, pimobendan, and milrinone on canine left ventricular-arterial coupling and mechanical efficiency.

    PubMed

    Pagel, P S; Hettrick, D A; Warltier, D C

    1996-01-01

    We examined and compared the effects of levosimendan, a new myofilament calcium sensitizer with phosphodiesterase inhibiting activity, pimobendan, and milrinone on left ventricular-arterial coupling and mechanical efficiency in 21 experiments performed in open-chest, barbiturate-anesthetized dogs instrumented for measurement of aortic and left ventricular (LV) pressure (micromanometer-tipped catheter), +dP/dt, and LV volume (conductance catheter). Myocardial contractility was assessed with the end-systolic pressure-volume relation (Ees) and preload recruitable stroke work (Msw) generated from a series of differentially loaded LV pressure-volume diagrams. LV-arterial coupling and mechanical efficiency were determined by the ratio of Ees to effective arterial elastance (Ea; the ratio of end-systolic arterial pressure to stroke volume) and the ratio of stroke work (SW) to pressure-volume area (PVA), respectively. Levosimendan (0.75, 1.5, and 3.0 micrograms.kg-1.min-1) significantly (p < 0.05) increased heart rate, +dP/dt, and ejection fraction (EF) and decreased mean arterial pressure (MAP), pressure-work index (PWI; an estimate of myocardial-oxygen consumption), and LV systolic and end-diastolic pressures (LVSP and LVEDP) and volumes (EDV and ESV). Levosimendan-induced augmentation of myocardial contractility (Ees, Msw and +dP/dt) and reductions in LV afterload (Ea) caused increases in the Ees/Ea ratio (0.61 +/- 0.10 during control to 3.3 +/- 0.7 during the high dose) consistent with enhancement of LV-arterial coupling. Levosimendan increased SW/PVA (0.48 +/- 0.05 during control to 0.84 +/- 0.04 during the high dose), indicating this drug improves the transfer of myocardial potential energy to external work. Levosimendan also increased the ratio of SW to PWI (109 +/- 18 during control to 255 +/- 50 mmHg.min.100g during the high dose), suggesting that myocardial metabolic efficiency was improved as well. Like levosimendan, pimobendan and milrinone (10, 20, and 40 and

  10. Prevalence of significant carotid artery stenosis in Iranian patients with peripheral arterial disease.

    PubMed

    Bavil, Abolhassan Shakeri; Ghabili, Kamyar; Daneshmand, Seyed Ebrahim; Nemati, Masoud; Bavil, Moslem Shakeri; Namdar, Hossein; Shaafi, Sheyda

    2011-01-01

    Generalized screening for carotid artery stenosis with carotid duplex ultrasonography in patients with peripheral arterial disease is controversial. The aim of the present study was to determine the prevalence of significant internal carotid artery (ICA) stenosis in a group of Iranian patients with peripheral arterial disease. We prospectively screened 120 patients with a known diagnosis of peripheral vascular disease for carotid artery stenosis. Based on the angiographic assessment of abdominal aorta and arteries of the lower extremities, patients with stenosis greater than 70% in the lower extremity arteries were included. A group of healthy individuals aged ≥ 50 years was recruited as a control. Risk factors for atherosclerosis including smoking, diabetes mellitus, hyperlipidemia, ischemic heart disease, and cerebrovascular disease were recorded. Common carotid arteries (CCAs) and the origins of the internal and external arteries were scanned with B-mode ultrasonography. Significant ICA stenosis, > 70% ICA stenosis but less than near occlusion of the ICA, was diagnosed when the ICA/CCA peak systolic velocity ratio was ≥ 3.5. Ninety-five patients, with a mean age of 58.52 ± 11.04 years, were studied. Twenty-five patients had a history of smoking, six patients had a history of coronary artery disease, six patients had hypertension, and ten patients had diabetes mellitus. Significant ICA stenosis was present in four patients (4.2%) with peripheral arterial disease in one healthy individual (1%) of the control group (P > 0.05). In terms of the risk factors for atherosclerosis, no statistically significant relationship was found between individual atherosclerotic risk factors and significant ICA stenosis (P > 0.05). The prevalence of significant ICA stenosis in Iranian patients with peripheral arterial disease is low. In addition, there is no relationship between individual atherosclerotic risk factors and significant ICA stenosis.

  11. Spontaneous coronary artery dissection.

    PubMed

    Giacoppo, Daniele; Capodanno, Davide; Dangas, George; Tamburino, Corrado

    2014-07-15

    Spontaneous coronary artery dissection (SCAD) is a relatively rare and unexplored type of coronary disease. Although atherosclerosis, hormonal changes during pregnancy and connective tissue disorders might represent a sufficiently convincing explanation for some patients with SCAD, the many remaining cases display only a weak relationship with these causes. While on one side the clinical heterogeneity of SCAD masks a full understanding of their underlying pathophysiologic process, on the other side paucity of data and misleading presentations hamper the quick diagnosis and optimal management of this condition. A definite diagnosis of SCAD can be significantly facilitated by endovascular imaging techniques. In fact, intravascular ultrasound (IVUS) and optical coherence tomography (OCT) overcome the limitations of coronary angiography providing detailed endovascular morphologic information. In contrast, optimal treatment strategies for SCAD still represent a burning controversial question. Herein, we review the published data examining possible causes and investigating the best therapy for SCAD in different clinical scenarios.

  12. Arterial structure and function in vascular ageing: are you as old as your arteries?

    PubMed

    Thijssen, Dick H J; Carter, Sophie E; Green, Daniel J

    2016-04-15

    Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in traditional cardiovascular risk factors. Since some arteries exhibit differential susceptibility to atherosclerosis, generalisations regarding the impact of ageing in humans may be overly simplistic, whereas in vivo assessment of arterial function and health provide direct insight. Coronary and peripheral (conduit, resistance and skin) arteries demonstrate a gradual, age-related impairment in vascular function that is likely to be related to a reduction in endothelium-derived nitric oxide bioavailability and/or increased production of vasoconstrictors (e.g. endothelin-1). Increased exposure and impaired ability for defence mechanisms to resist oxidative stress and inflammation, but also cellular senescence processes, may contribute to age-related changes in vascular function and health. Arteries also undergo structural changes as they age. Gradual thickening of the arterial wall, changes in wall content (i.e. less elastin, advanced glycation end-products) and increase in conduit artery diameter are observed with older age and occur similarly in central and peripheral arteries. These changes in structure have important interactive effects on artery function, with increases in small and large arterial stiffness representing a characteristic change with older age. Importantly, direct measures of arterial function and structure predict future cardiovascular events, independent of age or other cardiovascular risk factors. Taken together, and given the differential susceptibility of arteries to atherosclerosis in humans, direct measurement of arterial function and health may help to distinguish between biological and chronological age-related change in arterial health in humans.

  13. Mechanical buckling of artery under pulsatile pressure.

    PubMed

    Liu, Qin; Han, Hai-Chao

    2012-04-30

    Tortuosity that often occurs in carotid and other arteries has been shown to be associated with high blood pressure, atherosclerosis, and other diseases. However the mechanisms of tortuosity development are not clear. Our previous studies have suggested that arteries buckling could be a possible mechanism for the initiation of tortuous shape but artery buckling under pulsatile flow condition has not been fully studied. The objectives of this study were to determine the artery critical buckling pressure under pulsatile pressure both experimentally and theoretically, and to elucidate the relationship of critical pressures under pulsatile flow, steady flow, and static pressure. We first tested the buckling pressures of porcine carotid arteries under these loading conditions, and then proposed a nonlinear elastic artery model to examine the buckling pressures under pulsatile pressure conditions. Experimental results showed that under pulsatile pressure arteries buckled when the peak pressures were approximately equal to the critical buckling pressures under static pressure. This was also confirmed by model simulations at low pulse frequencies. Our results provide an effective tool to predict artery buckling pressure under pulsatile pressure.

  14. Mechanical Buckling of Artery under Pulsatile Pressure

    PubMed Central

    Liu, Qin; Han, Hai-Chao

    2012-01-01

    Tortuosity that often occurs in carotid and other arteries has been shown to be associated with high blood pressure, atherosclerosis, and other diseases. However the mechanisms of tortuosity development are not clear. Our previous studies have suggested that arteries buckling could be a possible mechanism for the initiation of tortuous shape but artery buckling under pulsatile flow condition has not been fully studied. The objectives of this study were to determine the artery critical buckling pressure under pulsatile pressure both experimentally and theoretically, and to elucidate the relationship of critical pressures under pulsatile flow, steady flow, and static pressure. We first tested the buckling pressures of porcine carotid arteries under these loading conditions, and then proposed a nonlinear elastic artery model to examine the buckling pressures under pulsatile pressure conditions. Experimental results showed that under pulsatile pressure arteries buckled when the peak pressures were approximately equal to the critical buckling pressures under static pressure. This was also confirmed by model simulations at low pulse frequencies. Our results provide an effective tool to predict artery buckling pressure under pulsatile pressure. PMID:22356844

  15. Cooled artery extension

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor)

    1990-01-01

    An artery vapor trap. A heat pipe artery is constructed with an extension protruding from the evaporator end of the heat pipe beyond the active area of the evaporator. The vapor migrates into the artery extension because of gravity or liquid displacement, and cooling the extension condenses the vapor to liquid, thus preventing vapor lock in the working portion of the artery by removing vapor from within the active artery. The condensed liquid is then transported back to the evaporator by the capillary action of the artery extension itself or by wick located within the extension.

  16. Coronary Artery Anomalies

    MedlinePlus

    ... Center for Coronary Artery Anomalies Doctors at the Texas Heart Institute's Center for Coronary Artery Anomalies (CCAA) ... comments. Terms of Use and Privacy Policy © Copyright Texas Heart Institute All rights reserved.

  17. Carotid Artery Disease

    MedlinePlus

    ... coronary artery disease: High levels of low-density lipoprotein cholesterol (bad cholesterol) and triglycerides in the blood. High blood pressure Diabetes Smoking Family history of coronary artery disease Obesity ...

  18. Spontaneous Coronary Artery Dissection

    MedlinePlus

    ... artery dissection (SCAD). It's not yet clear what role these factors play in causing the disease. Common factors include: Female sex. Though spontaneous coronary artery dissection (SCAD) can occur ...

  19. Peripheral artery disease - legs

    MedlinePlus

    ... pale. When PAD becomes severe, you may have: Impotence Pain and cramps at night Pain or tingling ... emboli that block small arteries Coronary artery disease Impotence Open sores (ischemic ulcers on the lower legs) ...

  20. Retinal artery occlusion

    MedlinePlus

    ... These blockages are more likely if there is hardening of the arteries ( atherosclerosis ) in the eye. Clots ... Blindness and vision loss Blood clots Diabetes Glaucoma Hardening of the arteries High blood cholesterol levels High ...

  1. Radial Artery Catheterization

    MedlinePlus

    ... of the radial artery for cardiac catheterization procedures. Advantages of Radial Artery Catheterization Any catheter placement into ... walk, and eat immediately. This is a particular advantage for patients with back problems because there is ...

  2. Hardening of the arteries

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000171.htm Hardening of the arteries To use the sharing features on this page, please enable JavaScript. Hardening of the arteries, also called atherosclerosis, occurs when ...

  3. Carotid artery surgery - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100124.htm Carotid artery surgery - series—Normal anatomy To use the sharing ... out of 4 Overview There are four carotid arteries, with a pair located on each side of ...

  4. Peripheral artery bypass - leg

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/007394.htm Peripheral artery bypass - leg To use the sharing features on this page, please enable JavaScript. Peripheral artery bypass is surgery to reroute the blood supply ...

  5. Uterine artery embolization

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/007384.htm Uterine artery embolization To use the sharing features on this page, please enable JavaScript. Uterine artery embolization (UAE) is a procedure to treat fibroids ...

  6. Coronary artery fistula

    MedlinePlus

    Congenital heart defect - coronary artery fistula; Birth defect heart - coronary artery fistula ... attaches to one of the chambers of the heart (the atrium or ventricle) or another blood vessel ( ...

  7. Coronary Artery Disease

    MedlinePlus

    Coronary artery disease (CAD) is the most common type of heart disease. It is the leading cause of death in the United States in both men and women. CAD happens when the arteries that supply blood to ...

  8. Coronary artery disease

    MedlinePlus Videos and Cool Tools

    ... heart muscle itself. Damage to or blockage of a coronary artery can result in injury to the heart. Normally, blood flows through a coronary artery unimpeded. However, a process called atherosclerosis ...

  9. What Is Peripheral Artery Disease?

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Peripheral Artery Disease? Peripheral artery disease (P.A.D.) is ... that affects blood flow to the legs. Normal Artery and Artery With Plaque Buildup The illustration shows ...

  10. The Relationship of Coronary Artery Calcium To Coronary Heart Disease Events is Similar in Young and Elderly Participants in The Multi-Ethnic Study of Atherosclerosis: A Secondary Analysis of a Prospective Population-based Cohort

    PubMed Central

    Tota-Maharaj, Rajesh; Blaha, Michael J.; Blankstein, Ron; Silverman, Michael; Eng, John; Shaw, Leslee J.; Blumenthal, Roger S.; Budoff, Matthew J.; Nasir, Khurram

    2015-01-01

    Objective To evaluate the relationship of coronary artery calcium (CAC) to coronary heart disease (CHD) events among young and elderly individuals. Participants and Methods This is a secondary analysis of data from a prospective, multi-ethnic, population-based cohort study designed to study subclinical atherosclerosis. A total of 6809 persons aged 45 to 84 years old without known cardiovascular disease at baseline were enrolled from July 2000-September 2002. All participants had CAC scoring performed, and were followed up for a median of 8.5 years. The main outcome measures studied were CHD events, defined as myocardial infarction, definite angina or probable angina followed by revascularization, resuscitated cardiac arrest or death attributable to coronary heart disease. Results Comparing individuals with CAC=0 to those with CAC > 100, there was an increased incidence of CHD events from 1 to 21/1000 person-years, and 2 to 23/1000 person-years in the 45-54 and 75-84 year old age groups respectively. Compared to CAC=0, CAC 1-100 and CAC >100 impart an increased multi-variable adjusted CHD event risk in both the 45-54 and 75-84 year old age groups [HR (95% CI): 45-54 years old, CAC 1-100: 2.3 (0.9-5.8), CAC>100: 12.4 (5.1-30.0); 75-84 years old, CAC 1-100: 5.4 (1.2-23.8), CAC>100: 12.1 (2.9-50.2)]. Conclusions Increased CAC imparts an increased CHD risk in younger and elderly individuals, suggesting that once CAC is known chronologic age has less importance. The utility of CAC scoring as a risk-stratification tool extends both to younger and elderly patients. PMID:25236430

  11. Renal artery aneurysms.

    PubMed

    González, J; Esteban, M; Andrés, G; Linares, E; Martínez-Salamanca, J I

    2014-01-01

    A renal artery aneurysm is defined as a dilated segment of renal artery that exceeds twice the diameter of a normal renal artery. Although rare, the diagnosis and incidence of this entity have been steadily increasing due to the routine use of cross-sectional imaging. In certain cases, renal artery aneurysms may be clinically important and potentially lethal. However, knowledge of their occurrence, their natural history, and their prognosis with or without treatment is still limited. This article aims to review the recent literature concerning renal artery aneurysms, with special consideration given to physiopathology, indications for treatment, different technical options, post-procedure complications and treatment outcomes.

  12. Extracranial vertebral artery intervention.

    PubMed

    Mukherjee, Debabrata; Pineda, Guillermo

    2007-12-01

    Atherosclerosis is the commonest cause of vertebral artery stenosis and has a predilection for the origin and proximal section of the extracranial portion of the vessel and also the intracranial portion of the vessel. Although it has generally been thought that extracranial vertebral artery (ECVA) disease has a more benign outcome compared to intracranial vertebral artery disease, significant occlusive disease of the proximal vertebral artery is the primary cause of vertebral artery ischemia in a significant proportion of patients. We focus on the interventional management of patients with proximal ECVA disease in this article.

  13. External artery heat pipe

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

    1989-01-01

    An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

  14. Jet pump assisted artery

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

  15. Transradial artery coronary angioplasty.

    PubMed

    Kiemeneij, F; Laarman, G J; de Melker, E

    1995-01-01

    This study explored the feasibility and safety of percutaneous coronary balloon angioplasty (PTCA) with miniaturized PTCA equipment via the radial artery. Coronary angioplasty (PTCA) via the femoral or brachial arteries may be associated with rare vascular complications such as bleeding and damage to the artery and adjacent structures. It was postulated that PTCA via the radial artery with miniaturized angioplasty equipment is feasible and that no major puncture site-related complications occur because hemostasis is obtained easily and because no major structures are near the radial artery. With double blood supply to the hand, radial artery occlusion is well tolerated. In 100 patients with collateral blood supply to the right hand, PTCA was attempted with 6F guiding catheters and rapid-exchange balloon catheters for exertional angina (87 patients) or nonexertional angina (13 patients). Angioplasty was attempted in 122 lesions (type A n = 67 [55%], Type B n = 37 [30%], and type C n = 18 [15%]). Pre- and post-PTCA computerized quantitative coronary analysis was performed. Radial artery function and structure were assessed clinically and with Doppler and two-dimensional ultrasound on the day of discharge. Coronary catheterization via the radial artery was successful in 94 patients (94%). The 6 remaining patients had successful PTCA via the femoral artery (n = 5) or the brachial artery (n = 1). Procedural success (120 of 122 lesions) was achieved in 92 patients (98%) via the radial artery and in 98 patients of the total study population.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Spontaneous Coronary Artery Dissection during Cabergoline Therapy

    PubMed Central

    Mehta, Nishaki Kiran; Malkani, Samir; Ockene, Ira

    2012-01-01

    Although spontaneous coronary artery dissection is a rare cause of acute coronary syndrome, it should be considered during the evaluation of patients who have chest pain. Coronary vasospasm can lead to spontaneous dissection. The dopamine agonist cabergoline is known to cause digital vasospasm. Herein, we report a case of spontaneous right coronary artery dissection in a 43-year-old woman who was taking cabergoline as therapy for prolactinoma. To our knowledge, this is the first report of an apparent relationship between cabergoline therapy and spontaneous coronary artery dissection. The possible association of cabergoline with coronary artery spasm and dissection should be considered in patients who present with chest pain while taking this medication. PMID:22412238

  17. Hepatocellular carcinomas smaller than 4 cm supplied by the intercostal artery: can we predict which intercostal artery supplies the tumor?

    PubMed

    Hur, Saebeom; Kim, Hyo-Cheol; Chung, Jin Wook; Kim, Min-Uk; Kim, Ji Dae; Kim, Gyoung Min; Lee, In Joon; Kim, Young Il; Jae, Hwan Jun; Park, Jae Hyung

    2011-01-01

    To predict which intercostal artery supplies a tumor by examining the spatial relationship between hepatocellular carcinoma (HCC) and the intercostal artery feeding the tumor on transverse computed tomography (CT) images. Between January 2000 and September 2009, 46 intercostal arteries supplying HCCs smaller than 4 cm were noted in 44 patients, and CT scans and angiograms of these patients were retrospectively reviewed. The intercostal artery feeding the tumor was marked on the CT scan showing the center of the tumor. In addition, its spatial relationship with the tumor center was examined. The angle of the tumor location was measured on the transverse CT scan in the clockwise direction from the sagittal line on the virtual circle centered in the right hemithorax. Correlations between the angle of the tumor location and the level of the tumor-feeding intercostal artery were assessed with the Spearman rank coefficient. Of 46 intercostal arteries feeding HCC, 39 (85%) were the first ones observed from the tumor center in a counterclockwise direction on the transverse CT image containing the tumor center. The level of the tumor-feeding intercostal artery was significantly correlated with the angle of the tumor, as the posteriorly located tumor tends to be supplied by lower intercostal arteries, while the laterally located tumor by upper intercostal arteries (Spearman coefficient = -0.537; p < 0.001). We can predict the tumor feeder with an accuracy of 85% as the first intercostal artery encountered from the tumor center in a counterclockwise direction on a transverse CT image.

  18. Stroke and pituitary apoplexy revealing an internal carotid artery dissection.

    PubMed

    Cho, Tae-Hee; Rheims, Sylvain; Ritzenthaler, Thomas; Berthezene, Yves; Nighoghossian, Norbert

    2014-01-01

    A 40-year-old hypertensive woman experienced a left hemispheric stroke revealing an acute pituitary apoplexy and a dissection limited to the lacerum segment of the left internal carotid artery. The relationship between pituitary apoplexy and arterial dissection is discussed. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  19. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry

    PubMed Central

    Nam, Kweon-Ho; Kim, Juho; Ra, Gicheol; Lee, Chong Hyun; Paeng, Dong-Guk

    2015-01-01

    Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM) allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with the spectral

  20. Feasibility Study of Ex Ovo Chick Chorioallantoic Artery Model for Investigating Pulsatile Variation of Arterial Geometry.

    PubMed

    Nam, Kweon-Ho; Kim, Juho; Ra, Gicheol; Lee, Chong Hyun; Paeng, Dong-Guk

    2015-01-01

    Despite considerable research efforts on the relationship between arterial geometry and cardiovascular pathology, information is lacking on the pulsatile geometrical variation caused by arterial distensibility and cardiomotility because of the lack of suitable in vivo experimental models and the methodological difficulties in examining the arterial dynamics. We aimed to investigate the feasibility of using a chick embryo system as an experimental model for basic research on the pulsatile variation of arterial geometry. Optical microscope video images of various arterial shapes in chick chorioallantoic circulation were recorded from different locations and different embryo samples. The high optical transparency of the chorioallantoic membrane (CAM) allowed clear observation of tiny vessels and their movements. Systolic and diastolic changes in arterial geometry were visualized by detecting the wall boundaries from binary images. Several to hundreds of microns of wall displacement variations were recognized during a pulsatile cycle. The spatial maps of the wall motion harmonics and magnitude ratio of harmonic components were obtained by analyzing the temporal brightness variation at each pixel in sequential grayscale images using spectral analysis techniques. The local variations in the spectral characteristics of the arterial wall motion were reflected well in the analysis results. In addition, mapping the phase angle of the fundamental frequency identified the regional variations in the wall motion directivity and phase shift. Regional variations in wall motion phase angle and fundamental-to-second harmonic ratio were remarkable near the bifurcation area. In summary, wall motion in various arterial geometry including straight, curved and bifurcated shapes was well observed in the CAM artery model, and their local and cyclic variations could be characterized by Fourier and wavelet transforms of the acquired video images. The CAM artery model with the spectral

  1. [Clinical interpretation for the pressure-flow relationships in extrinsic allergic alveolitis and in interstitial lung disease pulmonary hypertension patients. Should we care for the lung, the pulmonary artery pressure or both?].

    PubMed

    Lupi-Herrera, Eulo; Santos-Martínez, Luis Efrén; Pulido, Tomás; Sandoval, Julio

    2009-01-01

    We sought to analyze exercise-derived mean pulmonary artery pressure (mPAP)-cardiac index (CI) relationship to expand the concepts regarding its nature and to better identify pulmonary hemodynamic responders to acute oxygen breathing (AO2B-99.5%) and to hydralazine (H) in extrinsic allergic alveolitis (EAA) and chronic interstitial lung disease (CILD) pulmonary hypertension (PH) patients. mPAP/CI and extrapolated pressure (Pext) to zero flow were obtained while breathing room air (BRA) and under AO2B-99.5% in 38 stable (EAA (n = 14) and CILD (n = 24)) patients with resting and exercising PH. Hemodynamic characteristics were analyzed for the entire cohort and separate for EAA and CILD patients. AO2B-99.5% was tested in cohorts, H only in CILD and the effect of long-term corticosteroid treatment in EAA patients. Lung biopsies (LB) were obtained to evaluate the inflammatory-fibrosis stage and the degree of vascular lesion in the entire cohort. LB studies reveal a predominant stage of inflammation associated with grade-I vascular lesion for EAA patients. A predominant stage for fibrosis (although moderate) over inflammation associated with grade-II vascular lesions were documented for CILD patients. mPAP/CI abnormal location were associated with hypoxemia/decreased mixed venous-PO2 and lung mechanics abnormalities for both cohorts. An abnormal slope (Sp: 4.13; 95% CI: 3.42-4.84 mmHg/L/min/m2) and a normal Pext value (7 +/- 1.9 mmHg) were found for EAA patients. On the contrary, a normal slope (Sp: 1.22; 95% CI: 0.47-1.99 mmHg/L/min/m2) and an abnormal Pext value (19.7 +/- 3.5 mmHg) were found for CILD patients. Hemodynamic conditions that did not change for the Sp (4.0; 95% CI: 3.18-4.82 mmHg/L/min/m2); however, were associated with a statistical significant decrease in parallel for mPAP/CI during AO2B-99.5% when compared to BRA (p < 0.01), although not to normal slope values (0.96; 95% CI: 0.41-1.37) or mPAP/CI location. For CILD patients, during AO2B-99.5% no change

  2. Pressure-volume-temperature behavior of γ-Fe2SiO4 (spinel) based on static compression measurements at 400° C

    NASA Astrophysics Data System (ADS)

    Plymate, T. G.; Stout, J. H.

    1994-10-01

    Thirteen energy-dispersive x-ray diffraction spectra for γ-Fe2SiO4 (spinel) collected in situ at 400° C and pressures to 24 GPa constitute the basis for an elevated-temperature static compression isotherm for this important high-pressure phase. A Murnaghan regression of these molar volume measurements yields 177.3 (±17.4) GPa and 5.4(±2.5) for the 400° C, room pressure values of the isothermal bulk modulus ( K P 0) and its first pressure derivative ( K' P 0), respectively. When compared to the room- Tdeterminations of K P 0 available in the literature, our 400° C K P 0 yields -4.1 (±6.2)×10-2 GPa/degree for the average value of (∂ K/∂ T) P 0 over the temperature interval 25° Crelationships to the temperature and pressure of the 400 km discontinuity suggests a ΔV R of approximately 8.4% at that depth, approximately 10% less than the 9.3% ΔV R at ambient conditions.

  3. Temporal and Spatial Variances in Arterial Spin-Labeling Are Inversely Related to Large-Artery Blood Velocity.

    PubMed

    Robertson, A D; Matta, G; Basile, V S; Black, S E; Macgowan, C K; Detre, J A; MacIntosh, B J

    2017-08-01

    The relationship between extracranial large-artery characteristics and arterial spin-labeling MR imaging may influence the quality of arterial spin-labeling-CBF images for older adults with and without vascular pathology. We hypothesized that extracranial arterial blood velocity can explain between-person differences in arterial spin-labeling data systematically across clinical populations. We performed consecutive pseudocontinuous arterial spin-labeling and phase-contrast MR imaging on 82 individuals (20-88 years of age, 50% women), including healthy young adults, healthy older adults, and older adults with cerebral small vessel disease or chronic stroke infarcts. We examined associations between extracranial phase-contrast hemodynamics and intracranial arterial spin-labeling characteristics, which were defined by labeling efficiency, temporal signal-to-noise ratio, and spatial coefficient of variation. Large-artery blood velocity was inversely associated with labeling efficiency (P = .007), temporal SNR (P < .001), and spatial coefficient of variation (P = .05) of arterial spin-labeling, after accounting for age, sex, and group. Correction for labeling efficiency on an individual basis led to additional group differences in GM-CBF compared to correction using a constant labeling efficiency. Between-subject arterial spin-labeling variance was partially explained by extracranial velocity but not cross-sectional area. Choosing arterial spin-labeling timing parameters with on-line knowledge of blood velocity may improve CBF quantification. © 2017 by American Journal of Neuroradiology.

  4. Pulmonary arterial hypertension in rats due to age-related arginase activation in intermittent hypoxia.

    PubMed

    Nara, Akina; Nagai, Hisashi; Shintani-Ishida, Kaori; Ogura, Sayoko; Shimosawa, Tatsuo; Kuwahira, Ichiro; Shirai, Mikiyasu; Yoshida, Ken-ichi

    2015-08-01

    Pulmonary arterial hypertension (PAH) is prevalent in patients with obstructive sleep apnea syndrome (OSAS). Aging induces arginase activation and reduces nitric oxide (NO) production in the arteries. Intermittent hypoxia (IH), conferred by cycles of brief hypoxia and normoxia, contributes to OSAS pathogenesis. Here, we studied the role of arginase and aging in the pathogenesis of PAH in adult (9-mo-old) and young (2-mo-old) male Sprague-Dawley rats subjected to IH or normoxia for 4 weeks and analyzed them with a pressure-volume catheter inserted into the right ventricle (RV) and by pulsed Doppler echocardiography. Western blot analysis was conducted on arginase, NO synthase isoforms, and nitrotyrosine. IH induced PAH, as shown by increased RV systolic pressure and RV hypertrophy, in adult rats but not in young rats. IH increased expression levels of arginase I and II proteins in the adult rats. IH also increased arginase I expression in the pulmonary artery endothelium and arginase II in the pulmonary artery adventitia. Furthermore, IH reduced pulmonary levels of nitrate and nitrite but increased nitrotyrosine levels in adult rats. An arginase inhibitor (N(ω)-hydroxy-nor-1-arginine) prevented IH-induced PAH and normalized nitrite and nitrate levels in adult rats. IH induced arginase up-regulation and PAH in adult rats, but not in young rats, through reduced NO production. Our findings suggest that arginase inhibition prevents or reverses PAH.

  5. Duplicated middle cerebral artery.

    PubMed

    Perez, Jesus; Machado, Calixto; Scherle, Claudio; Hierro, Daniel

    2009-01-01

    Duplicated middle cerebral artery (DMCA) is an anomalous vessel arising from the internal carotid artery. The incidence DMCA is relatively law, and an association between this anomaly and cerebral aneurysms has been documented. There is a controversy whether DMCA may have perforating arteries. This is an important fact to consider in aneurysm surgery. We report the case of a 34-year-old black woman who suffered a subarachnoid hemorrhage and the angiography a left DMCA, and an aneurysm in an inferior branch of the main MCA. The DMCA and the MCA had perforating arteries. The aneurysm was clipped without complications. The observation of perforating arteries in our patient confirms that the DMCA may have perforating arteries. This is very important to be considered in cerebral aneurysms surgery. Moreover, the DMCA may potentially serve as a collateral blood supply to the MCA territory in cases of MCA occlusion.